import java.io.*;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.net.SocketTimeoutException;
import java.net.URLDecoder;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.Charset;
import java.security.KeyStore;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.TimeZone;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.zip.GZIPOutputStream;

import javax.net.ssl.KeyManager;
import javax.net.ssl.KeyManagerFactory;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLServerSocket;
import javax.net.ssl.SSLServerSocketFactory;
import javax.net.ssl.TrustManagerFactory;

import NanoHTTPD.Response.IStatus;
import NanoHTTPD.Response.Status;

abstract class NanoHTTPD {

    /**
     * Pluggable strategy for asynchronously executing requests.
     */
    public interface AsyncRunner {

        void closeAll();

        void closed(ClientHandler clientHandler);

        void exec(ClientHandler code);
    }

    /**
     * The runnable that will be used for every new client connection.
     */
    public class ClientHandler implements Runnable {

        private final InputStream inputStream;

        private final Socket acceptSocket;

        private ClientHandler(InputStream inputStream, Socket acceptSocket) {
            this.inputStream = inputStream;
            this.acceptSocket = acceptSocket;
        }

        public void close() {
            safeClose(this.inputStream);
            safeClose(this.acceptSocket);
        }

        @Override
        public void run() {
            OutputStream outputStream = null;
            try {
                outputStream = this.acceptSocket.getOutputStream();
                TempFileManager tempFileManager = NanoHTTPD.this.tempFileManagerFactory.create();
                HTTPSession session = new HTTPSession(tempFileManager, this.inputStream, outputStream, this.acceptSocket.getInetAddress());
                while (!this.acceptSocket.isClosed()) {
                    session.execute();
                }
            } catch (Exception e) {
                // When the socket is closed by the client,
                // we throw our own SocketException
                // to break the "keep alive" loop above. If
                // the exception was anything other
                // than the expected SocketException OR a
                // SocketTimeoutException, print the
                // stacktrace
                if (!(e instanceof SocketException && "NanoHttpd Shutdown".equals(e.getMessage())) && !(e instanceof SocketTimeoutException)) {
                    NanoHTTPD.LOG.log(Level.FINE, "Communication with the client broken", e);
                }
            } finally {
                safeClose(outputStream);
                safeClose(this.inputStream);
                safeClose(this.acceptSocket);
                NanoHTTPD.this.asyncRunner.closed(this);
            }
        }
    }

    public static class Cookie {

        public static String getHTTPTime(int days) {
            Calendar calendar = Calendar.getInstance();
            SimpleDateFormat dateFormat = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss z", Locale.US);
            dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
            calendar.add(Calendar.DAY_OF_MONTH, days);
            return dateFormat.format(calendar.getTime());
        }

        private final String n, v, e;

        public Cookie(String name, String value) {
            this(name, value, 30);
        }

        public Cookie(String name, String value, int numDays) {
            this.n = name;
            this.v = value;
            this.e = getHTTPTime(numDays);
        }

        public Cookie(String name, String value, String expires) {
            this.n = name;
            this.v = value;
            this.e = expires;
        }

        public String getHTTPHeader() {
            String fmt = "%s=%s; expires=%s";
            return String.format(fmt, this.n, this.v, this.e);
        }
    }

    /**
     * Provides rudimentary support for cookies. Doesn't support 'path',
     * 'secure' nor 'httpOnly'. Feel free to improve it and/or add unsupported
     * features.
     * 
     * @author LordFokas
     */
    public class CookieHandler implements Iterable<String> {

        private final HashMap<String, String> cookies = new HashMap<String, String>();

        private final ArrayList<Cookie> queue = new ArrayList<Cookie>();

        public CookieHandler(Map<String, String> httpHeaders) {
            String raw = httpHeaders.get("cookie");
            if (raw != null) {
                String[] tokens = raw.split(";");
                for (String token : tokens) {
                    String[] data = token.trim().split("=");
                    if (data.length == 2) {
                        this.cookies.put(data[0], data[1]);
                    }
                }
            }
        }

        /**
         * Set a cookie with an expiration date from a month ago, effectively
         * deleting it on the client side.
         * 
         * @param name
         *            The cookie name.
         */
        public void delete(String name) {
            set(name, "-delete-", -30);
        }

        @Override
        public Iterator<String> iterator() {
            return this.cookies.keySet().iterator();
        }

        /**
         * Read a cookie from the HTTP Headers.
         * 
         * @param name
         *            The cookie's name.
         * @return The cookie's value if it exists, null otherwise.
         */
        public String read(String name) {
            return this.cookies.get(name);
        }

        public void set(Cookie cookie) {
            this.queue.add(cookie);
        }

        /**
         * Sets a cookie.
         * 
         * @param name
         *            The cookie's name.
         * @param value
         *            The cookie's value.
         * @param expires
         *            How many days until the cookie expires.
         */
        public void set(String name, String value, int expires) {
            this.queue.add(new Cookie(name, value, Cookie.getHTTPTime(expires)));
        }

        /**
         * Internally used by the webserver to add all queued cookies into the
         * Response's HTTP Headers.
         * 
         * @param response
         *            The Response object to which headers the queued cookies
         *            will be added.
         */
        public void unloadQueue(Response response) {
            for (Cookie cookie : this.queue) {
                response.addHeader("Set-Cookie", cookie.getHTTPHeader());
            }
        }
    }

    /**
     * Default threading strategy for NanoHTTPD.
     * <p/>
     * <p>
     * By default, the server spawns a new Thread for every incoming request.
     * These are set to <i>daemon</i> status, and named according to the request
     * number. The name is useful when profiling the application.
     * </p>
     */
    public static class DefaultAsyncRunner implements AsyncRunner {

        private long requestCount;

        private final List<ClientHandler> running = Collections.synchronizedList(new ArrayList<NanoHTTPD.ClientHandler>());

        /**
         * @return a list with currently running clients.
         */
        public List<ClientHandler> getRunning() {
            return running;
        }

        @Override
        public void closeAll() {
            // copy of the list for concurrency
            for (ClientHandler clientHandler : new ArrayList<ClientHandler>(this.running)) {
                clientHandler.close();
            }
        }

        @Override
        public void closed(ClientHandler clientHandler) {
            this.running.remove(clientHandler);
        }

        @Override
        public void exec(ClientHandler clientHandler) {
            ++this.requestCount;
            Thread t = new Thread(clientHandler);
            t.setDaemon(true);
            t.setName("NanoHttpd Request Processor (#" + this.requestCount + ")");
            this.running.add(clientHandler);
            t.start();
        }
    }

    /**
     * Default strategy for creating and cleaning up temporary files.
     * <p/>
     * <p>
     * By default, files are created by <code>File.createTempFile()</code> in
     * the directory specified.
     * </p>
     */
    public static class DefaultTempFile implements TempFile {

        private final File file;

        private final OutputStream fstream;

        public DefaultTempFile(String tempdir) throws IOException {
            this.file = File.createTempFile("NanoHTTPD-", "", new File(tempdir));
            this.fstream = new FileOutputStream(this.file);
        }

        @Override
        public void delete() throws Exception {
            safeClose(this.fstream);
            if (!this.file.delete()) {
                throw new Exception("could not delete temporary file");
            }
        }

        @Override
        public String getName() {
            return this.file.getAbsolutePath();
        }

        @Override
        public OutputStream open() throws Exception {
            return this.fstream;
        }
    }

    /**
     * Default strategy for creating and cleaning up temporary files.
     * <p/>
     * <p>
     * This class stores its files in the standard location (that is, wherever
     * <code>java.io.tmpdir</code> points to). Files are added to an internal
     * list, and deleted when no longer needed (that is, when
     * <code>clear()</code> is invoked at the end of processing a request).
     * </p>
     */
    public static class DefaultTempFileManager implements TempFileManager {

        private final String tmpdir;

        private final List<TempFile> tempFiles;

        public DefaultTempFileManager() {
            this.tmpdir = System.getProperty("java.io.tmpdir");
            this.tempFiles = new ArrayList<TempFile>();
        }

        @Override
        public void clear() {
            for (TempFile file : this.tempFiles) {
                try {
                    file.delete();
                } catch (Exception ignored) {
                    NanoHTTPD.LOG.log(Level.WARNING, "could not delete file ", ignored);
                }
            }
            this.tempFiles.clear();
        }

        @Override
        public TempFile createTempFile() throws Exception {
            DefaultTempFile tempFile = new DefaultTempFile(this.tmpdir);
            this.tempFiles.add(tempFile);
            return tempFile;
        }
    }

    /**
     * Default strategy for creating and cleaning up temporary files.
     */
    private class DefaultTempFileManagerFactory implements TempFileManagerFactory {

        @Override
        public TempFileManager create() {
            return new DefaultTempFileManager();
        }
    }

    private static final String CONTENT_DISPOSITION_REGEX = "([ |\t]*Content-Disposition[ |\t]*:)(.*)";

    private static final Pattern CONTENT_DISPOSITION_PATTERN = Pattern.compile(CONTENT_DISPOSITION_REGEX, Pattern.CASE_INSENSITIVE);

    private static final String CONTENT_TYPE_REGEX = "([ |\t]*content-type[ |\t]*:)(.*)";

    private static final Pattern CONTENT_TYPE_PATTERN = Pattern.compile(CONTENT_TYPE_REGEX, Pattern.CASE_INSENSITIVE);

    private static final String CONTENT_DISPOSITION_ATTRIBUTE_REGEX = "[ |\t]*([a-zA-Z]*)[ |\t]*=[ |\t]*['|\"]([^\"^']*)['|\"]";

    private static final Pattern CONTENT_DISPOSITION_ATTRIBUTE_PATTERN = Pattern.compile(CONTENT_DISPOSITION_ATTRIBUTE_REGEX);

    protected class HTTPSession implements IHTTPSession {

        public static final int BUFSIZE = 8192;

        private final TempFileManager tempFileManager;

        private final OutputStream outputStream;

        private final PushbackInputStream inputStream;

        private int splitbyte;

        private int rlen;

        private String uri;

        private Method method;

        private Map<String, String> parms;

        private Map<String, String> headers;

        private CookieHandler cookies;

        private String queryParameterString;

        private String remoteIp;

        private String protocolVersion;

        public HTTPSession(TempFileManager tempFileManager, InputStream inputStream, OutputStream outputStream) {
            this.tempFileManager = tempFileManager;
            this.inputStream = new PushbackInputStream(inputStream, HTTPSession.BUFSIZE);
            this.outputStream = outputStream;
        }

        public HTTPSession(TempFileManager tempFileManager, InputStream inputStream, OutputStream outputStream, InetAddress inetAddress) {
            this.tempFileManager = tempFileManager;
            this.inputStream = new PushbackInputStream(inputStream, HTTPSession.BUFSIZE);
            this.outputStream = outputStream;
            this.remoteIp = inetAddress.isLoopbackAddress() || inetAddress.isAnyLocalAddress() ? "127.0.0.1" : inetAddress.getHostAddress().toString();
            this.headers = new HashMap<String, String>();
        }

        /**
         * Decodes the sent headers and loads the data into Key/value pairs
         */
        private void decodeHeader(BufferedReader in, Map<String, String> pre, Map<String, String> parms, Map<String, String> headers) throws ResponseException {
            try {
                // Read the request line
                String inLine = in.readLine();
                if (inLine == null) {
                    return;
                }

                StringTokenizer st = new StringTokenizer(inLine);
                if (!st.hasMoreTokens()) {
                    throw new ResponseException(Response.Status.BAD_REQUEST, "BAD REQUEST: Syntax error. Usage: GET /example/file.html");
                }

                pre.put("method", st.nextToken());

                if (!st.hasMoreTokens()) {
                    throw new ResponseException(Response.Status.BAD_REQUEST, "BAD REQUEST: Missing URI. Usage: GET /example/file.html");
                }

                String uri = st.nextToken();

                // Decode parameters from the URI
                int qmi = uri.indexOf('?');
                if (qmi >= 0) {
                    decodeParms(uri.substring(qmi + 1), parms);
                    uri = decodePercent(uri.substring(0, qmi));
                } else {
                    uri = decodePercent(uri);
                }

                // If there's another token, its protocol version,
                // followed by HTTP headers.
                // NOTE: this now forces header names lower case since they are
                // case insensitive and vary by client.
                if (st.hasMoreTokens()) {
                    protocolVersion = st.nextToken();
                } else {
                    protocolVersion = "HTTP/1.1";
                    NanoHTTPD.LOG.log(Level.FINE, "no protocol version specified, strange. Assuming HTTP/1.1.");
                }
                String line = in.readLine();
                while (line != null && line.trim().length() > 0) {
                    int p = line.indexOf(':');
                    if (p >= 0) {
                        headers.put(line.substring(0, p).trim().toLowerCase(Locale.US), line.substring(p + 1).trim());
                    }
                    line = in.readLine();
                }

                pre.put("uri", uri);
            } catch (IOException ioe) {
                throw new ResponseException(Response.Status.INTERNAL_ERROR, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage(), ioe);
            }
        }

        /**
         * Decodes the Multipart Body data and put it into Key/Value pairs.
         */
        private void decodeMultipartFormData(String boundary, ByteBuffer fbuf, Map<String, String> parms, Map<String, String> files) throws ResponseException {
            try {
                int[] boundary_idxs = getBoundaryPositions(fbuf, boundary.getBytes());
                if (boundary_idxs.length < 2) {
                    throw new ResponseException(Response.Status.BAD_REQUEST, "BAD REQUEST: Content type is multipart/form-data but contains less than two boundary strings.");
                }

                final int MAX_HEADER_SIZE = 1024;
                byte[] part_header_buff = new byte[MAX_HEADER_SIZE];
                for (int bi = 0; bi < boundary_idxs.length - 1; bi++) {
                    fbuf.position(boundary_idxs[bi]);
                    int len = (fbuf.remaining() < MAX_HEADER_SIZE) ? fbuf.remaining() : MAX_HEADER_SIZE;
                    fbuf.get(part_header_buff, 0, len);
                    ByteArrayInputStream bais = new ByteArrayInputStream(part_header_buff, 0, len);
                    BufferedReader in = new BufferedReader(new InputStreamReader(bais, Charset.forName("US-ASCII")));

                    // First line is boundary string
                    String mpline = in.readLine();
                    if (!mpline.contains(boundary)) {
                        throw new ResponseException(Response.Status.BAD_REQUEST, "BAD REQUEST: Content type is multipart/form-data but chunk does not start with boundary.");
                    }

                    String part_name = null, file_name = null, content_type = null;
                    // Parse the reset of the header lines
                    mpline = in.readLine();
                    while (mpline != null && mpline.trim().length() > 0) {
                        Matcher matcher = CONTENT_DISPOSITION_PATTERN.matcher(mpline);
                        if (matcher.matches()) {
                            String attributeString = matcher.group(2);
                            matcher = CONTENT_DISPOSITION_ATTRIBUTE_PATTERN.matcher(attributeString);
                            while (matcher.find()) {
                                String key = matcher.group(1);
                                if (key.equalsIgnoreCase("name")) {
                                    part_name = matcher.group(2);
                                } else if (key.equalsIgnoreCase("filename")) {
                                    file_name = matcher.group(2);
                                }
                            }
                        }
                        matcher = CONTENT_TYPE_PATTERN.matcher(mpline);
                        if (matcher.matches()) {
                            content_type = matcher.group(2).trim();
                        }
                        mpline = in.readLine();
                    }

                    // Read the part data
                    int part_header_len = len - (int) in.skip(MAX_HEADER_SIZE);
                    if (part_header_len >= len - 4) {
                        throw new ResponseException(Response.Status.INTERNAL_ERROR, "Multipart header size exceeds MAX_HEADER_SIZE.");
                    }
                    int part_data_start = boundary_idxs[bi] + part_header_len;
                    int part_data_end = boundary_idxs[bi + 1] - 4;

                    fbuf.position(part_data_start);
                    if (content_type == null) {
                        // Read the part into a string
                        byte[] data_bytes = new byte[part_data_end - part_data_start];
                        fbuf.get(data_bytes);
                        parms.put(part_name, new String(data_bytes));
                    } else {
                        // Read it into a file
                        String path = saveTmpFile(fbuf, part_data_start, part_data_end - part_data_start);
                        if (!files.containsKey(part_name)) {
                            files.put(part_name, path);
                        } else {
                            int count = 2;
                            while (files.containsKey(part_name + count)) {
                                count++;
                            }
                            files.put(part_name + count, path);
                        }
                        parms.put(part_name, file_name);
                    }
                }
            } catch (ResponseException re) {
                throw re;
            } catch (Exception e) {
                throw new ResponseException(Response.Status.INTERNAL_ERROR, e.toString());
            }
        }

        /**
         * Decodes parameters in percent-encoded URI-format ( e.g.
         * "name=Jack%20Daniels&pass=Single%20Malt" ) and adds them to given
         * Map. NOTE: this doesn't support multiple identical keys due to the
         * simplicity of Map.
         */
        private void decodeParms(String parms, Map<String, String> p) {
            if (parms == null) {
                this.queryParameterString = "";
                return;
            }

            this.queryParameterString = parms;
            StringTokenizer st = new StringTokenizer(parms, "&");
            while (st.hasMoreTokens()) {
                String e = st.nextToken();
                int sep = e.indexOf('=');
                if (sep >= 0) {
                    p.put(decodePercent(e.substring(0, sep)).trim(), decodePercent(e.substring(sep + 1)));
                } else {
                    p.put(decodePercent(e).trim(), "");
                }
            }
        }

        @Override
        public void execute() throws IOException {
            Response r = null;
            try {
                // Read the first 8192 bytes.
                // The full header should fit in here.
                // Apache's default header limit is 8KB.
                // Do NOT assume that a single read will get the entire header
                // at once!
                byte[] buf = new byte[HTTPSession.BUFSIZE];
                this.splitbyte = 0;
                this.rlen = 0;

                int read = -1;
                try {
                    read = this.inputStream.read(buf, 0, HTTPSession.BUFSIZE);
                } catch (Exception e) {
                    safeClose(this.inputStream);
                    safeClose(this.outputStream);
                    throw new SocketException("NanoHttpd Shutdown");
                }
                if (read == -1) {
                    // socket was been closed
                    safeClose(this.inputStream);
                    safeClose(this.outputStream);
                    throw new SocketException("NanoHttpd Shutdown");
                }
                while (read > 0) {
                    this.rlen += read;
                    this.splitbyte = findHeaderEnd(buf, this.rlen);
                    if (this.splitbyte > 0) {
                        break;
                    }
                    read = this.inputStream.read(buf, this.rlen, HTTPSession.BUFSIZE - this.rlen);
                }

                if (this.splitbyte < this.rlen) {
                    this.inputStream.unread(buf, this.splitbyte, this.rlen - this.splitbyte);
                }

                this.parms = new HashMap<String, String>();
                if (null == this.headers) {
                    this.headers = new HashMap<String, String>();
                } else {
                    this.headers.clear();
                }

                if (null != this.remoteIp) {
                    this.headers.put("remote-addr", this.remoteIp);
                    this.headers.put("http-client-ip", this.remoteIp);
                }

                // Create a BufferedReader for parsing the header.
                BufferedReader hin = new BufferedReader(new InputStreamReader(new ByteArrayInputStream(buf, 0, this.rlen)));

                // Decode the header into parms and header java properties
                Map<String, String> pre = new HashMap<String, String>();
                decodeHeader(hin, pre, this.parms, this.headers);

                this.method = Method.lookup(pre.get("method"));
                if (this.method == null) {
                    throw new ResponseException(Response.Status.BAD_REQUEST, "BAD REQUEST: Syntax error.");
                }

                this.uri = pre.get("uri");

                this.cookies = new CookieHandler(this.headers);

                String connection = this.headers.get("connection");
                boolean keepAlive = protocolVersion.equals("HTTP/1.1") && (connection == null || !connection.matches("(?i).*close.*"));

                // Ok, now do the serve()
                r = serve(this);
                if (r == null) {
                    throw new ResponseException(Response.Status.INTERNAL_ERROR, "SERVER INTERNAL ERROR: Serve() returned a null response.");
                } else {
                    String acceptEncoding = this.headers.get("accept-encoding");
                    this.cookies.unloadQueue(r);
                    r.setRequestMethod(this.method);
                    r.setGzipEncoding(useGzipWhenAccepted(r) && acceptEncoding != null && acceptEncoding.contains("gzip"));
                    r.setKeepAlive(keepAlive);
                    r.send(this.outputStream);
                }
                if (!keepAlive || "close".equalsIgnoreCase(r.getHeader("connection"))) {
                    throw new SocketException("NanoHttpd Shutdown");
                }
            } catch (SocketException e) {
                // throw it out to close socket object (finalAccept)
                throw e;
            } catch (SocketTimeoutException ste) {
                // treat socket timeouts the same way we treat socket exceptions
                // i.e. close the stream & finalAccept object by throwing the
                // exception up the call stack.
                throw ste;
            } catch (IOException ioe) {
                Response resp = newFixedLengthResponse(Response.Status.INTERNAL_ERROR, NanoHTTPD.MIME_PLAINTEXT, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage());
                resp.send(this.outputStream);
                safeClose(this.outputStream);
            } catch (ResponseException re) {
                Response resp = newFixedLengthResponse(re.getStatus(), NanoHTTPD.MIME_PLAINTEXT, re.getMessage());
                resp.send(this.outputStream);
                safeClose(this.outputStream);
            } finally {
                safeClose(r);
                this.tempFileManager.clear();
            }
        }

        /**
         * Find byte index separating header from body. It must be the last byte
         * of the first two sequential new lines.
         */
        private int findHeaderEnd(final byte[] buf, int rlen) {
            int splitbyte = 0;
            while (splitbyte + 3 < rlen) {
                if (buf[splitbyte] == '\r' && buf[splitbyte + 1] == '\n' && buf[splitbyte + 2] == '\r' && buf[splitbyte + 3] == '\n') {
                    return splitbyte + 4;
                }
                splitbyte++;
            }
            return 0;
        }

        /**
         * Find the byte positions where multipart boundaries start. This reads
         * a large block at a time and uses a temporary buffer to optimize
         * (memory mapped) file access.
         */
        private int[] getBoundaryPositions(ByteBuffer b, byte[] boundary) {
            int[] res = new int[0];
            if (b.remaining() < boundary.length) {
                return res;
            }

            int search_window_pos = 0;
            byte[] search_window = new byte[4 * 1024 + boundary.length];

            int first_fill = (b.remaining() < search_window.length) ? b.remaining() : search_window.length;
            b.get(search_window, 0, first_fill);
            int new_bytes = first_fill - boundary.length;

            do {
                // Search the search_window
                for (int j = 0; j < new_bytes; j++) {
                    for (int i = 0; i < boundary.length; i++) {
                        if (search_window[j + i] != boundary[i])
                            break;
                        if (i == boundary.length - 1) {
                            // Match found, add it to results
                            int[] new_res = new int[res.length + 1];
                            System.arraycopy(res, 0, new_res, 0, res.length);
                            new_res[res.length] = search_window_pos + j;
                            res = new_res;
                        }
                    }
                }
                search_window_pos += new_bytes;

                // Copy the end of the buffer to the start
                System.arraycopy(search_window, search_window.length - boundary.length, search_window, 0, boundary.length);

                // Refill search_window
                new_bytes = search_window.length - boundary.length;
                new_bytes = (b.remaining() < new_bytes) ? b.remaining() : new_bytes;
                b.get(search_window, boundary.length, new_bytes);
            } while (new_bytes > 0);
            return res;
        }

        @Override
        public CookieHandler getCookies() {
            return this.cookies;
        }

        @Override
        public final Map<String, String> getHeaders() {
            return this.headers;
        }

        @Override
        public final InputStream getInputStream() {
            return this.inputStream;
        }

        @Override
        public final Method getMethod() {
            return this.method;
        }

        @Override
        public final Map<String, String> getParms() {
            return this.parms;
        }

        @Override
        public String getQueryParameterString() {
            return this.queryParameterString;
        }

        private RandomAccessFile getTmpBucket() {
            try {
                TempFile tempFile = this.tempFileManager.createTempFile();
                return new RandomAccessFile(tempFile.getName(), "rw");
            } catch (Exception e) {
                throw new Error(e); // we won't recover, so throw an error
            }
        }

        @Override
        public final String getUri() {
            return this.uri;
        }

        @Override
        public void parseBody(Map<String, String> files) throws IOException, ResponseException {
            final int REQUEST_BUFFER_LEN = 512;
            final int MEMORY_STORE_LIMIT = 1024;
            RandomAccessFile randomAccessFile = null;
            try {
                long size;
                if (this.headers.containsKey("content-length")) {
                    size = Integer.parseInt(this.headers.get("content-length"));
                } else if (this.splitbyte < this.rlen) {
                    size = this.rlen - this.splitbyte;
                } else {
                    size = 0;
                }

                ByteArrayOutputStream baos = null;
                DataOutput request_data_output = null;

                // Store the request in memory or a file, depending on size
                if (size < MEMORY_STORE_LIMIT) {
                    baos = new ByteArrayOutputStream();
                    request_data_output = new DataOutputStream(baos);
                } else {
                    randomAccessFile = getTmpBucket();
                    request_data_output = randomAccessFile;
                }

                // Read all the body and write it to request_data_output
                byte[] buf = new byte[REQUEST_BUFFER_LEN];
                while (this.rlen >= 0 && size > 0) {
                    this.rlen = this.inputStream.read(buf, 0, (int) Math.min(size, REQUEST_BUFFER_LEN));
                    size -= this.rlen;
                    if (this.rlen > 0) {
                        request_data_output.write(buf, 0, this.rlen);
                    }
                }

                ByteBuffer fbuf = null;
                if (baos != null) {
                    fbuf = ByteBuffer.wrap(baos.toByteArray(), 0, baos.size());
                } else {
                    fbuf = randomAccessFile.getChannel().map(FileChannel.MapMode.READ_ONLY, 0, randomAccessFile.length());
                    randomAccessFile.seek(0);
                }

                // If the method is POST, there may be parameters
                // in data section, too, read it:
                if (Method.POST.equals(this.method)) {
                    String contentType = "";
                    String contentTypeHeader = this.headers.get("content-type");

                    StringTokenizer st = null;
                    if (contentTypeHeader != null) {
                        st = new StringTokenizer(contentTypeHeader, ",; ");
                        if (st.hasMoreTokens()) {
                            contentType = st.nextToken();
                        }
                    }

                    if ("multipart/form-data".equalsIgnoreCase(contentType)) {
                        // Handle multipart/form-data
                        if (!st.hasMoreTokens()) {
                            throw new ResponseException(Response.Status.BAD_REQUEST,
                                    "BAD REQUEST: Content type is multipart/form-data but boundary missing. Usage: GET /example/file.html");
                        }

                        String boundaryStartString = "boundary=";
                        int boundaryContentStart = contentTypeHeader.indexOf(boundaryStartString) + boundaryStartString.length();
                        String boundary = contentTypeHeader.substring(boundaryContentStart, contentTypeHeader.length());
                        if (boundary.startsWith("\"") && boundary.endsWith("\"")) {
                            boundary = boundary.substring(1, boundary.length() - 1);
                        }

                        decodeMultipartFormData(boundary, fbuf, this.parms, files);
                    } else {
                        byte[] postBytes = new byte[fbuf.remaining()];
                        fbuf.get(postBytes);
                        String postLine = new String(postBytes).trim();
                        // Handle application/x-www-form-urlencoded
                        if ("application/x-www-form-urlencoded".equalsIgnoreCase(contentType)) {
                            decodeParms(postLine, this.parms);
                        } else if (postLine.length() != 0) {
                            // Special case for raw POST data => create a
                            // special files entry "postData" with raw content
                            // data
                            files.put("postData", postLine);
                        }
                    }
                } else if (Method.PUT.equals(this.method)) {
                    files.put("content", saveTmpFile(fbuf, 0, fbuf.limit()));
                }
            } finally {
                safeClose(randomAccessFile);
            }
        }

        /**
         * Retrieves the content of a sent file and saves it to a temporary
         * file. The full path to the saved file is returned.
         */
        private String saveTmpFile(ByteBuffer b, int offset, int len) {
            String path = "";
            if (len > 0) {
                FileOutputStream fileOutputStream = null;
                try {
                    TempFile tempFile = this.tempFileManager.createTempFile();
                    ByteBuffer src = b.duplicate();
                    fileOutputStream = new FileOutputStream(tempFile.getName());
                    FileChannel dest = fileOutputStream.getChannel();
                    src.position(offset).limit(offset + len);
                    dest.write(src.slice());
                    path = tempFile.getName();
                } catch (Exception e) { // Catch exception if any
                    throw new Error(e); // we won't recover, so throw an error
                } finally {
                    safeClose(fileOutputStream);
                }
            }
            return path;
        }
    }

    /**
     * Handles one session, i.e. parses the HTTP request and returns the
     * response.
     */
    public interface IHTTPSession {

        void execute() throws IOException;

        CookieHandler getCookies();

        Map<String, String> getHeaders();

        InputStream getInputStream();

        Method getMethod();

        Map<String, String> getParms();

        String getQueryParameterString();

        /**
         * @return the path part of the URL.
         */
        String getUri();

        /**
         * Adds the files in the request body to the files map.
         * 
         * @param files
         *            map to modify
         */
        void parseBody(Map<String, String> files) throws IOException, ResponseException;
    }

    /**
     * HTTP Request methods, with the ability to decode a <code>String</code>
     * back to its enum value.
     */
    public enum Method {
        GET,
        PUT,
        POST,
        DELETE,
        HEAD,
        OPTIONS,
        TRACE,
        CONNECT,
        PATCH;

        static Method lookup(String method) {
            for (Method m : Method.values()) {
                if (m.toString().equalsIgnoreCase(method)) {
                    return m;
                }
            }
            return null;
        }
    }

    /**
     * HTTP response. Return one of these from serve().
     */
    public static class Response implements Closeable {

        public interface IStatus {

            String getDescription();

            int getRequestStatus();
        }

        /**
         * Some HTTP response status codes
         */
        public enum Status implements IStatus {
            SWITCH_PROTOCOL(101, "Switching Protocols"),
            OK(200, "OK"),
            CREATED(201, "Created"),
            ACCEPTED(202, "Accepted"),
            NO_CONTENT(204, "No Content"),
            PARTIAL_CONTENT(206, "Partial Content"),
            REDIRECT(301, "Moved Permanently"),
            NOT_MODIFIED(304, "Not Modified"),
            BAD_REQUEST(400, "Bad Request"),
            UNAUTHORIZED(401, "Unauthorized"),
            FORBIDDEN(403, "Forbidden"),
            NOT_FOUND(404, "Not Found"),
            METHOD_NOT_ALLOWED(405, "Method Not Allowed"),
            REQUEST_TIMEOUT(408, "Request Timeout"),
            RANGE_NOT_SATISFIABLE(416, "Requested Range Not Satisfiable"),
            INTERNAL_ERROR(500, "Internal Server Error"),
            UNSUPPORTED_HTTP_VERSION(505, "HTTP Version Not Supported");

            private final int requestStatus;

            private final String description;

            Status(int requestStatus, String description) {
                this.requestStatus = requestStatus;
                this.description = description;
            }

            @Override
            public String getDescription() {
                return "" + this.requestStatus + " " + this.description;
            }

            @Override
            public int getRequestStatus() {
                return this.requestStatus;
            }

        }

        /**
         * Output stream that will automatically send every write to the wrapped
         * OutputStream according to chunked transfer:
         * http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.6.1
         */
        private static class ChunkedOutputStream extends FilterOutputStream {

            public ChunkedOutputStream(OutputStream out) {
                super(out);
            }

            @Override
            public void write(int b) throws IOException {
                byte[] data = {
                    (byte) b
                };
                write(data, 0, 1);
            }

            @Override
            public void write(byte[] b) throws IOException {
                write(b, 0, b.length);
            }

            @Override
            public void write(byte[] b, int off, int len) throws IOException {
                if (len == 0)
                    return;
                out.write(String.format("%x\r\n", len).getBytes());
                out.write(b, off, len);
                out.write("\r\n".getBytes());
            }

            public void finish() throws IOException {
                out.write("0\r\n\r\n".getBytes());
            }

        }

        /**
         * HTTP status code after processing, e.g. "200 OK", Status.OK
         */
        private IStatus status;

        /**
         * MIME type of content, e.g. "text/html"
         */
        private String mimeType;

        /**
         * Data of the response, may be null.
         */
        private InputStream data;

        private long contentLength;

        /**
         * Headers for the HTTP response. Use addHeader() to add lines.
         */
        private final Map<String, String> header = new HashMap<String, String>();

        /**
         * The request method that spawned this response.
         */
        private Method requestMethod;

        /**
         * Use chunkedTransfer
         */
        private boolean chunkedTransfer;

        private boolean encodeAsGzip;

        private boolean keepAlive;

        /**
         * Creates a fixed length response if totalBytes>=0, otherwise chunked.
         */
        protected Response(IStatus status, String mimeType, InputStream data, long totalBytes) {
            this.status = status;
            this.mimeType = mimeType;
            if (data == null) {
                this.data = new ByteArrayInputStream(new byte[0]);
                this.contentLength = 0L;
            } else {
                this.data = data;
                this.contentLength = totalBytes;
            }
            this.chunkedTransfer = this.contentLength < 0;
            keepAlive = true;
        }

        @Override
        public void close() throws IOException {
            if (this.data != null) {
                this.data.close();
            }
        }

        /**
         * Adds given line to the header.
         */
        public void addHeader(String name, String value) {
            this.header.put(name, value);
        }

        public InputStream getData() {
            return this.data;
        }

        public String getHeader(String name) {
            for (String headerName : header.keySet()) {
                if (headerName.equalsIgnoreCase(name)) {
                    return header.get(headerName);
                }
            }
            return null;
        }

        public String getMimeType() {
            return this.mimeType;
        }

        public Method getRequestMethod() {
            return this.requestMethod;
        }

        public IStatus getStatus() {
            return this.status;
        }

        public void setGzipEncoding(boolean encodeAsGzip) {
            this.encodeAsGzip = encodeAsGzip;
        }

        public void setKeepAlive(boolean useKeepAlive) {
            this.keepAlive = useKeepAlive;
        }

        private boolean headerAlreadySent(Map<String, String> header, String name) {
            boolean alreadySent = false;
            for (String headerName : header.keySet()) {
                alreadySent |= headerName.equalsIgnoreCase(name);
            }
            return alreadySent;
        }

        /**
         * Sends given response to the socket.
         */
        protected void send(OutputStream outputStream) {
            String mime = this.mimeType;
            SimpleDateFormat gmtFrmt = new SimpleDateFormat("E, d MMM yyyy HH:mm:ss 'GMT'", Locale.US);
            gmtFrmt.setTimeZone(TimeZone.getTimeZone("GMT"));

            try {
                if (this.status == null) {
                    throw new Error("sendResponse(): Status can't be null.");
                }
                PrintWriter pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8")), false);
                pw.print("HTTP/1.1 " + this.status.getDescription() + " \r\n");

                if (mime != null) {
                    pw.print("Content-Type: " + mime + "\r\n");
                }

                if (this.header == null || this.header.get("Date") == null) {
                    pw.print("Date: " + gmtFrmt.format(new Date()) + "\r\n");
                }

                if (this.header != null) {
                    for (String key : this.header.keySet()) {
                        String value = this.header.get(key);
                        pw.print(key + ": " + value + "\r\n");
                    }
                }

                if (!headerAlreadySent(header, "connection")) {
                    pw.print("Connection: " + (this.keepAlive ? "keep-alive" : "close") + "\r\n");
                }

                if (headerAlreadySent(this.header, "content-length")) {
                    encodeAsGzip = false;
                }

                if (encodeAsGzip) {
                    pw.print("Content-Encoding: gzip\r\n");
                    setChunkedTransfer(true);
                }

                long pending = this.data != null ? this.contentLength : 0;
                if (this.requestMethod != Method.HEAD && this.chunkedTransfer) {
                    pw.print("Transfer-Encoding: chunked\r\n");
                } else if (!encodeAsGzip) {
                    pending = sendContentLengthHeaderIfNotAlreadyPresent(pw, this.header, pending);
                }
                pw.print("\r\n");
                pw.flush();
                sendBodyWithCorrectTransferAndEncoding(outputStream, pending);
                outputStream.flush();
                safeClose(this.data);
            } catch (IOException ioe) {
                NanoHTTPD.LOG.log(Level.SEVERE, "Could not send response to the client", ioe);
            }
        }

        private void sendBodyWithCorrectTransferAndEncoding(OutputStream outputStream, long pending) throws IOException {
            if (this.requestMethod != Method.HEAD && this.chunkedTransfer) {
                ChunkedOutputStream chunkedOutputStream = new ChunkedOutputStream(outputStream);
                sendBodyWithCorrectEncoding(chunkedOutputStream, -1);
                chunkedOutputStream.finish();
            } else {
                sendBodyWithCorrectEncoding(outputStream, pending);
            }
        }

        private void sendBodyWithCorrectEncoding(OutputStream outputStream, long pending) throws IOException {
            if (encodeAsGzip) {
                GZIPOutputStream gzipOutputStream = new GZIPOutputStream(outputStream);
                sendBody(gzipOutputStream, -1);
                gzipOutputStream.finish();
            } else {
                sendBody(outputStream, pending);
            }
        }

        /**
         * Sends the body to the specified OutputStream. The pending parameter
         * limits the maximum amounts of bytes sent unless it is -1, in which
         * case everything is sent.
         * 
         * @param outputStream
         *            the OutputStream to send data to
         * @param pending
         *            -1 to send everything, otherwise sets a max limit to the
         *            number of bytes sent
         * @throws IOException
         *             if something goes wrong while sending the data.
         */
        private void sendBody(OutputStream outputStream, long pending) throws IOException {
            long BUFFER_SIZE = 16 * 1024;
            byte[] buff = new byte[(int) BUFFER_SIZE];
            boolean sendEverything = pending == -1;
            while (pending > 0 || sendEverything) {
                long bytesToRead = sendEverything ? BUFFER_SIZE : Math.min(pending, BUFFER_SIZE);
                int read = this.data.read(buff, 0, (int) bytesToRead);
                if (read <= 0) {
                    break;
                }
                outputStream.write(buff, 0, read);
                if (!sendEverything) {
                    pending -= read;
                }
            }
        }

        protected long sendContentLengthHeaderIfNotAlreadyPresent(PrintWriter pw, Map<String, String> header, long size) {
            for (String headerName : header.keySet()) {
                if (headerName.equalsIgnoreCase("content-length")) {
                    try {
                        return Long.parseLong(header.get(headerName));
                    } catch (NumberFormatException ex) {
                        return size;
                    }
                }
            }

            pw.print("Content-Length: " + size + "\r\n");
            return size;
        }

        public void setChunkedTransfer(boolean chunkedTransfer) {
            this.chunkedTransfer = chunkedTransfer;
        }

        public void setData(InputStream data) {
            this.data = data;
        }

        public void setMimeType(String mimeType) {
            this.mimeType = mimeType;
        }

        public void setRequestMethod(Method requestMethod) {
            this.requestMethod = requestMethod;
        }

        public void setStatus(IStatus status) {
            this.status = status;
        }
    }

    public static final class ResponseException extends Exception {

        private static final long serialVersionUID = 6569838532917408380L;

        private final Response.Status status;

        public ResponseException(Response.Status status, String message) {
            super(message);
            this.status = status;
        }

        public ResponseException(Response.Status status, String message, Exception e) {
            super(message, e);
            this.status = status;
        }

        public Response.Status getStatus() {
            return this.status;
        }
    }

    /**
     * The runnable that will be used for the main listening thread.
     */
    public class ServerRunnable implements Runnable {

        private final int timeout;

        private IOException bindException;

        private boolean hasBinded = false;

        private ServerRunnable(int timeout) {
            this.timeout = timeout;
        }

        @Override
        public void run() {
            try {
                myServerSocket.bind(hostname != null ? new InetSocketAddress(hostname, myPort) : new InetSocketAddress(myPort));
                hasBinded = true;
            } catch (IOException e) {
                this.bindException = e;
                return;
            }
            do {
                try {
                    final Socket finalAccept = NanoHTTPD.this.myServerSocket.accept();
                    if (this.timeout > 0) {
                        finalAccept.setSoTimeout(this.timeout);
                    }
                    final InputStream inputStream = finalAccept.getInputStream();
                    NanoHTTPD.this.asyncRunner.exec(createClientHandler(finalAccept, inputStream));
                } catch (IOException e) {
                    NanoHTTPD.LOG.log(Level.FINE, "Communication with the client broken", e);
                }
            } while (!NanoHTTPD.this.myServerSocket.isClosed());
        }
    }

    /**
     * A temp file.
     * <p/>
     * <p>
     * Temp files are responsible for managing the actual temporary storage and
     * cleaning themselves up when no longer needed.
     * </p>
     */
    public interface TempFile {

        void delete() throws Exception;

        String getName();

        OutputStream open() throws Exception;
    }

    /**
     * Temp file manager.
     * <p/>
     * <p>
     * Temp file managers are created 1-to-1 with incoming requests, to create
     * and cleanup temporary files created as a result of handling the request.
     * </p>
     */
    public interface TempFileManager {

        void clear();

        TempFile createTempFile() throws Exception;
    }

    /**
     * Factory to create temp file managers.
     */
    public interface TempFileManagerFactory {

        TempFileManager create();
    }

    /**
     * Maximum time to wait on Socket.getInputStream().read() (in milliseconds)
     * This is required as the Keep-Alive HTTP connections would otherwise block
     * the socket reading thread forever (or as long the browser is open).
     */
    public static final int SOCKET_READ_TIMEOUT = 5000;

    /**
     * Common MIME type for dynamic content: plain text
     */
    public static final String MIME_PLAINTEXT = "text/plain";

    /**
     * Common MIME type for dynamic content: html
     */
    public static final String MIME_HTML = "text/html";

    /**
     * Pseudo-Parameter to use to store the actual query string in the
     * parameters map for later re-processing.
     */
    private static final String QUERY_STRING_PARAMETER = "NanoHttpd.QUERY_STRING";

    /**
     * logger to log to.
     */
    private static final Logger LOG = Logger.getLogger(NanoHTTPD.class.getName());

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a loaded KeyStore and an
     * array of loaded KeyManagers. These objects must properly
     * loaded/initialized by the caller.
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(KeyStore loadedKeyStore, KeyManager[] keyManagers) throws IOException {
        SSLServerSocketFactory res = null;
        try {
            TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            trustManagerFactory.init(loadedKeyStore);
            SSLContext ctx = SSLContext.getInstance("TLS");
            ctx.init(keyManagers, trustManagerFactory.getTrustManagers(), null);
            res = ctx.getServerSocketFactory();
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
        return res;
    }

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a loaded KeyStore and a
     * loaded KeyManagerFactory. These objects must properly loaded/initialized
     * by the caller.
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(KeyStore loadedKeyStore, KeyManagerFactory loadedKeyFactory) throws IOException {
        SSLServerSocketFactory res = null;
        try {
            TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            trustManagerFactory.init(loadedKeyStore);
            SSLContext ctx = SSLContext.getInstance("TLS");
            ctx.init(loadedKeyFactory.getKeyManagers(), trustManagerFactory.getTrustManagers(), null);
            res = ctx.getServerSocketFactory();
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
        return res;
    }

    /**
     * Creates an SSLSocketFactory for HTTPS. Pass a KeyStore resource with your
     * certificate and passphrase
     */
    public static SSLServerSocketFactory makeSSLSocketFactory(String keyAndTrustStoreClasspathPath, char[] passphrase) throws IOException {
        SSLServerSocketFactory res = null;
        try {
            KeyStore keystore = KeyStore.getInstance(KeyStore.getDefaultType());
            InputStream keystoreStream = NanoHTTPD.class.getResourceAsStream(keyAndTrustStoreClasspathPath);
            keystore.load(keystoreStream, passphrase);
            TrustManagerFactory trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
            trustManagerFactory.init(keystore);
            KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
            keyManagerFactory.init(keystore, passphrase);
            SSLContext ctx = SSLContext.getInstance("TLS");
            ctx.init(keyManagerFactory.getKeyManagers(), trustManagerFactory.getTrustManagers(), null);
            res = ctx.getServerSocketFactory();
        } catch (Exception e) {
            throw new IOException(e.getMessage());
        }
        return res;
    }

    private static final void safeClose(Object closeable) {
        try {
            if (closeable != null) {
                if (closeable instanceof Closeable) {
                    ((Closeable) closeable).close();
                } else if (closeable instanceof Socket) {
                    ((Socket) closeable).close();
                } else if (closeable instanceof ServerSocket) {
                    ((ServerSocket) closeable).close();
                } else {
                    throw new IllegalArgumentException("Unknown object to close");
                }
            }
        } catch (IOException e) {
            NanoHTTPD.LOG.log(Level.SEVERE, "Could not close", e);
        }
    }

    private final String hostname;

    private final int myPort;

    private ServerSocket myServerSocket;

    private SSLServerSocketFactory sslServerSocketFactory;

    private Thread myThread;

    /**
     * Pluggable strategy for asynchronously executing requests.
     */
    protected AsyncRunner asyncRunner;

    /**
     * Pluggable strategy for creating and cleaning up temporary files.
     */
    private TempFileManagerFactory tempFileManagerFactory;

    /**
     * Constructs an HTTP server on given port.
     */
    public NanoHTTPD(int port) {
        this(null, port);
    }

    // -------------------------------------------------------------------------------
    // //
    //
    // Threading Strategy.
    //
    // -------------------------------------------------------------------------------
    // //

    /**
     * Constructs an HTTP server on given hostname and port.
     */
    public NanoHTTPD(String hostname, int port) {
        this.hostname = hostname;
        this.myPort = port;
        setTempFileManagerFactory(new DefaultTempFileManagerFactory());
        setAsyncRunner(new DefaultAsyncRunner());
    }

    /**
     * Forcibly closes all connections that are open.
     */
    public synchronized void closeAllConnections() {
        stop();
    }

    /**
     * create a instance of the client handler, subclasses can return a subclass
     * of the ClientHandler.
     * 
     * @param finalAccept
     *            the socket the cleint is connected to
     * @param inputStream
     *            the input stream
     * @return the client handler
     */
    protected ClientHandler createClientHandler(final Socket finalAccept, final InputStream inputStream) {
        return new ClientHandler(inputStream, finalAccept);
    }

    /**
     * Instantiate the server runnable, can be overwritten by subclasses to
     * provide a subclass of the ServerRunnable.
     * 
     * @param timeout
     *            the socet timeout to use.
     * @return the server runnable.
     */
    protected ServerRunnable createServerRunnable(final int timeout) {
        return new ServerRunnable(timeout);
    }

    /**
     * Decode parameters from a URL, handing the case where a single parameter
     * name might have been supplied several times, by return lists of values.
     * In general these lists will contain a single element.
     * 
     * @param parms
     *            original <b>NanoHTTPD</b> parameters values, as passed to the
     *            <code>serve()</code> method.
     * @return a map of <code>String</code> (parameter name) to
     *         <code>List&lt;String&gt;</code> (a list of the values supplied).
     */
    protected Map<String, List<String>> decodeParameters(Map<String, String> parms) {
        return this.decodeParameters(parms.get(NanoHTTPD.QUERY_STRING_PARAMETER));
    }

    // -------------------------------------------------------------------------------
    // //

    /**
     * Decode parameters from a URL, handing the case where a single parameter
     * name might have been supplied several times, by return lists of values.
     * In general these lists will contain a single element.
     * 
     * @param queryString
     *            a query string pulled from the URL.
     * @return a map of <code>String</code> (parameter name) to
     *         <code>List&lt;String&gt;</code> (a list of the values supplied).
     */
    protected Map<String, List<String>> decodeParameters(String queryString) {
        Map<String, List<String>> parms = new HashMap<String, List<String>>();
        if (queryString != null) {
            StringTokenizer st = new StringTokenizer(queryString, "&");
            while (st.hasMoreTokens()) {
                String e = st.nextToken();
                int sep = e.indexOf('=');
                String propertyName = sep >= 0 ? decodePercent(e.substring(0, sep)).trim() : decodePercent(e).trim();
                if (!parms.containsKey(propertyName)) {
                    parms.put(propertyName, new ArrayList<String>());
                }
                String propertyValue = sep >= 0 ? decodePercent(e.substring(sep + 1)) : null;
                if (propertyValue != null) {
                    parms.get(propertyName).add(propertyValue);
                }
            }
        }
        return parms;
    }

    /**
     * Decode percent encoded <code>String</code> values.
     * 
     * @param str
     *            the percent encoded <code>String</code>
     * @return expanded form of the input, for example "foo%20bar" becomes
     *         "foo bar"
     */
    protected String decodePercent(String str) {
        String decoded = null;
        try {
            decoded = URLDecoder.decode(str, "UTF8");
        } catch (UnsupportedEncodingException ignored) {
            NanoHTTPD.LOG.log(Level.WARNING, "Encoding not supported, ignored", ignored);
        }
        return decoded;
    }

    /**
     * @return true if the gzip compression should be used if the client
     *         accespts it. Default this option is on for text content and off
     *         for everything else.
     */
    protected boolean useGzipWhenAccepted(Response r) {
        return r.getMimeType() != null && r.getMimeType().toLowerCase().contains("text/");
    }

    public final int getListeningPort() {
        return this.myServerSocket == null ? -1 : this.myServerSocket.getLocalPort();
    }

    public final boolean isAlive() {
        return wasStarted() && !this.myServerSocket.isClosed() && this.myThread.isAlive();
    }

    /**
     * Call before start() to serve over HTTPS instead of HTTP
     */
    public void makeSecure(SSLServerSocketFactory sslServerSocketFactory) {
        this.sslServerSocketFactory = sslServerSocketFactory;
    }

    /**
     * Create a response with unknown length (using HTTP 1.1 chunking).
     */
    public Response newChunkedResponse(IStatus status, String mimeType, InputStream data) {
        return new Response(status, mimeType, data, -1);
    }

    /**
     * Create a response with known length.
     */
    public Response newFixedLengthResponse(IStatus status, String mimeType, InputStream data, long totalBytes) {
        return new Response(status, mimeType, data, totalBytes);
    }

    /**
     * Create a text response with known length.
     */
    public Response newFixedLengthResponse(IStatus status, String mimeType, String txt) {
        if (txt == null) {
            return newFixedLengthResponse(status, mimeType, new ByteArrayInputStream(new byte[0]), 0);
        } else {
            byte[] bytes;
            try {
                bytes = txt.getBytes("UTF-8");
            } catch (UnsupportedEncodingException e) {
                NanoHTTPD.LOG.log(Level.SEVERE, "encoding problem, responding nothing", e);
                bytes = new byte[0];
            }
            return newFixedLengthResponse(status, mimeType, new ByteArrayInputStream(bytes), bytes.length);
        }
    }

    /**
     * Create a text response with known length.
     */
    public Response newFixedLengthResponse(String msg) {
        return newFixedLengthResponse(Status.OK, NanoHTTPD.MIME_HTML, msg);
    }

    /**
     * Override this to customize the server.
     * <p/>
     * <p/>
     * (By default, this returns a 404 "Not Found" plain text error response.)
     * 
     * @param session
     *            The HTTP session
     * @return HTTP response, see class Response for details
     */
    public Response serve(IHTTPSession session) {
        Map<String, String> files = new HashMap<String, String>();
        Method method = session.getMethod();
        if (Method.PUT.equals(method) || Method.POST.equals(method)) {
            try {
                session.parseBody(files);
            } catch (IOException ioe) {
                return newFixedLengthResponse(Response.Status.INTERNAL_ERROR, NanoHTTPD.MIME_PLAINTEXT, "SERVER INTERNAL ERROR: IOException: " + ioe.getMessage());
            } catch (ResponseException re) {
                return newFixedLengthResponse(re.getStatus(), NanoHTTPD.MIME_PLAINTEXT, re.getMessage());
            }
        }

        Map<String, String> parms = session.getParms();
        parms.put(NanoHTTPD.QUERY_STRING_PARAMETER, session.getQueryParameterString());
        return serve(session.getUri(), method, session.getHeaders(), parms, files);
    }

    /**
     * Override this to customize the server.
     * <p/>
     * <p/>
     * (By default, this returns a 404 "Not Found" plain text error response.)
     * 
     * @param uri
     *            Percent-decoded URI without parameters, for example
     *            "/index.cgi"
     * @param method
     *            "GET", "POST" etc.
     * @param parms
     *            Parsed, percent decoded parameters from URI and, in case of
     *            POST, data.
     * @param headers
     *            Header entries, percent decoded
     * @return HTTP response, see class Response for details
     */
    @Deprecated
    public Response serve(String uri, Method method, Map<String, String> headers, Map<String, String> parms, Map<String, String> files) {
        return newFixedLengthResponse(Response.Status.NOT_FOUND, NanoHTTPD.MIME_PLAINTEXT, "Not Found");
    }

    /**
     * Pluggable strategy for asynchronously executing requests.
     * 
     * @param asyncRunner
     *            new strategy for handling threads.
     */
    public void setAsyncRunner(AsyncRunner asyncRunner) {
        this.asyncRunner = asyncRunner;
    }

    /**
     * Pluggable strategy for creating and cleaning up temporary files.
     * 
     * @param tempFileManagerFactory
     *            new strategy for handling temp files.
     */
    public void setTempFileManagerFactory(TempFileManagerFactory tempFileManagerFactory) {
        this.tempFileManagerFactory = tempFileManagerFactory;
    }

    /**
     * Start the server.
     * 
     * @throws IOException
     *             if the socket is in use.
     */
    public void start() throws IOException {
        start(NanoHTTPD.SOCKET_READ_TIMEOUT);
    }

    /**
     * Start the server.
     * 
     * @param timeout
     *            timeout to use for socket connections.
     * @throws IOException
     *             if the socket is in use.
     */
    public void start(final int timeout) throws IOException {
        if (this.sslServerSocketFactory != null) {
            SSLServerSocket ss = (SSLServerSocket) this.sslServerSocketFactory.createServerSocket();
            ss.setNeedClientAuth(false);
            this.myServerSocket = ss;
        } else {
            this.myServerSocket = new ServerSocket();
        }
        this.myServerSocket.setReuseAddress(true);

        ServerRunnable serverRunnable = createServerRunnable(timeout);
        this.myThread = new Thread(serverRunnable);
        this.myThread.setDaemon(true);
        this.myThread.setName("NanoHttpd Main Listener");
        this.myThread.start();
        while (!serverRunnable.hasBinded && serverRunnable.bindException == null) {
            try {
                Thread.sleep(10L);
            } catch (Throwable e) {
                // on android this may not be allowed, that's why we
                // catch throwable the wait should be very short because we are
                // just waiting for the bind of the socket
            }
        }
        if (serverRunnable.bindException != null) {
            throw serverRunnable.bindException;
        }
    }

    /**
     * Stop the server.
     */
    public void stop() {
        try {
            safeClose(this.myServerSocket);
            this.asyncRunner.closeAll();
            if (this.myThread != null) {
                this.myThread.join();
            }
        } catch (Exception e) {
            NanoHTTPD.LOG.log(Level.SEVERE, "Could not stop all connections", e);
        }
    }

    public final boolean wasStarted() {
        return this.myServerSocket != null && this.myThread != null;
    }
}

Began life as a copy of #1000408