)A)
if (alphabet.contains(a)) return true;
return false;
}
/**
* Creates a clone of this Alphabet
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Alphabet
.
*/
public Object clone() {
return new Match(A);
}
}
//NonMatch
/**
* This class implements an {@link Lexicon.Alphabet Alphabet
} containing all except some characters.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class NonMatch extends Match {
/**
* Constructs an Alphabet
containing all characters except one, and builds the NFA constructed from this Expression
.
*
* @param a the character not in this Alphabet
.
*/
public NonMatch(char a) {
super(a);
}
/**
* Constructs an Alphabet
containing all characters except some, and builds the NFA constructed from this Expression
.
*
* @param A the {@link Character} or {@link String} of characters not in this Alphabet
.
*/
public NonMatch(Object A) {
super(A);
}
/**
* Indicates whether a character occurs in this Alphabet
.
*
* @param a the character whose status is requested.
* @return true
if a
occurs in this Alphabet
; false
otherwise.
*/
boolean contains(char a) {
return a != (char)-1 && !super.contains(a);
}
/**
* Creates a clone of this Alphabet
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Alphabet
.
*/
public Object clone() {
return new NonMatch(A);
}
}
//Range
/**
* This class implements an {@link Lexicon.Alphabet Alphabet
} containing the characters in a range.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class Range extends Alphabet {
/**
* The first character in the range.
*/
private final char a1;
/**
* The last character in the range.
*/
private final char a2;
/**
* Constructs an Alphabet
containing the characters in a range, and builds the NFA constructed from this Expression
.
*
* @param a1 the first character in the range.
* @param a2 the last character in the range.
*/
public Range(char a1, char a2) {
this.a1 = a1;
this.a2 = a2;
put(i = s(), this, f = s());
}
/**
* Indicates whether a character occurs in this Alphabet
.
*
* @param a the character whose status is requested.
* @return true
if a
occurs in this Alphabet
; false
otherwise.
*/
boolean contains(char a) {
return a1 <= a && a <= a2;
}
/**
* Creates a clone of this Alphabet
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Alphabet
.
*/
public Object clone() {
return new Range(a1, a2);
}
}
/**
* This class implements an {@link Lexicon.Alphabet Alphabet
} containing the characters in a POSIX character class.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class PosixClass extends Alphabet {
/**
* The bit mask representing this PosixClass
.
*/
private final int posixClass;
/**
* Constructs an Alphabet
containing the characters in a POSIX character class, and builds the NFA constructed from this Expression
.
*
* @param posixClass the bit mask representing this PosixClass
.
*/
private PosixClass(int posixClass) {
this.posixClass = posixClass;
put(i = s(), this, f = s());
}
/**
* Creates an Alphabet
containing the uppercase alphabetic characters.
*
* @return an Alphabet
containing the uppercase alphabetic characters.
*/
public static PosixClass upper() {
return new PosixClass(0x0001);
}
/**
* Creates an Alphabet
containing the lowercase alphabetic characters.
*
* @return an Alphabet
containing the lowercase alphabetic characters.
*/
public static PosixClass lower() {
return new PosixClass(0x0002);
}
/**
* Creates an Alphabet
containing the alphabetic characters.
*
* @return an Alphabet
containing the alphabetic characters.
*/
public static PosixClass alpha() {
return new PosixClass(0x0004);
}
/**
* Creates an Alphabet
containing the decimal digit characters.
*
* @return an Alphabet
containing the decimal digit characters.
*/
public static PosixClass digit() {
return new PosixClass(0x0008);
}
/**
* Creates an Alphabet
containing the hexadecimal digit characters.
*
* @return an Alphabet
containing the hexadecimal digit characters.
*/
public static PosixClass xdigit() {
return new PosixClass(0x0010);
}
/**
* Creates an Alphabet
containing the alphanumeric characters.
*
* @return an Alphabet
containing the alphanumeric characters.
*/
public static PosixClass alnum() {
return new PosixClass(0x0020);
}
/**
* Creates an Alphabet
containing the punctuation characters.
*
* @return an Alphabet
containing the punctuation characters.
*/
public static PosixClass punct() {
return new PosixClass(0x0040);
}
/**
* Creates an Alphabet
containing the graphical characters.
*
* @return an Alphabet
containing the graphical characters.
*/
public static PosixClass graph() {
return new PosixClass(0x0080);
}
/**
* Creates an Alphabet
containing the printable characters.
*
* @return an Alphabet
containing the printable characters.
*/
public static PosixClass print() {
return new PosixClass(0x0100);
}
/**
* Creates an Alphabet
containing the blank characters.
*
* @return an Alphabet
containing the blank characters.
*/
public static PosixClass blank() {
return new PosixClass(0x0200);
}
/**
* Creates an Alphabet
containing the space characters.
*
* @return an Alphabet
containing the space characters.
*/
public static PosixClass space() {
return new PosixClass(0x0400);
}
/**
* Creates an Alphabet
containing the control characters.
*
* @return an Alphabet
containing the control characters.
*/
public static PosixClass cntrl() {
return new PosixClass(0x0800);
}
/**
* Indicates whether a character occurs in this Alphabet
.
*
* @param a the character whose status is requested.
* @return true
if a
occurs in this Alphabet
; false
otherwise.
*/
boolean contains(char a) {
int UPPER = 0x0001; int LOWER = 0x0002;
int ALPHA = 0x0004; int DIGIT = 0x0008;
int XDIGIT = 0x0010; int ALNUM = 0x0020;
int PUNCT = 0x0040; int GRAPH = 0x0080;
int PRINT = 0x0100; int BLANK = 0x0200;
int SPACE = 0x0400; int CNTRL = 0x0800;
int classes = 0;
switch (Character.getType(a)) {
default: break;
case Character.UPPERCASE_LETTER:
classes |= UPPER | ALPHA | (('A' <= a && a <= 'F') ? XDIGIT : 0) | ALNUM | GRAPH | PRINT; break;
case Character.LOWERCASE_LETTER:
classes |= LOWER | ALPHA | (('a' <= a && a <= 'f') ? XDIGIT : 0) | ALNUM | GRAPH | PRINT; break;
case Character.TITLECASE_LETTER:
case Character.MODIFIER_LETTER:
case Character.OTHER_LETTER:
classes |= ALPHA | ALNUM | GRAPH | PRINT; break;
case Character.NON_SPACING_MARK:
case Character.COMBINING_SPACING_MARK:
case Character.ENCLOSING_MARK:
classes |= PUNCT | GRAPH | PRINT; break;
case Character.DECIMAL_DIGIT_NUMBER:
classes |= DIGIT | XDIGIT | ALNUM | GRAPH | PRINT; break;
case Character.LETTER_NUMBER:
case Character.OTHER_NUMBER:
classes |= ALNUM | GRAPH | PRINT; break;
case Character.CONNECTOR_PUNCTUATION:
case Character.DASH_PUNCTUATION:
case Character.START_PUNCTUATION:
case Character.END_PUNCTUATION:
case Character.INITIAL_QUOTE_PUNCTUATION:
case Character.FINAL_QUOTE_PUNCTUATION:
case Character.OTHER_PUNCTUATION:
case Character.MATH_SYMBOL:
case Character.CURRENCY_SYMBOL:
case Character.MODIFIER_SYMBOL:
case Character.OTHER_SYMBOL:
classes |= PUNCT | GRAPH | PRINT; break;
case Character.SPACE_SEPARATOR:
classes |= PRINT | BLANK | SPACE; break;
case Character.LINE_SEPARATOR:
case Character.PARAGRAPH_SEPARATOR:
break;
case Character.CONTROL:
classes |= ((a == '\t') ? BLANK : 0) | ((a == '\t' || a == '\n' || a == '\013' || a == '\f' || a == '\r') ? SPACE : 0) | CNTRL; break;
case Character.FORMAT:
case Character.SURROGATE:
case Character.PRIVATE_USE:
case Character.UNASSIGNED:
break;
}
return (classes & posixClass) != 0;
}
/**
* Creates a clone of this Alphabet
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Alphabet
.
*/
public Object clone() {
return new PosixClass(posixClass);
}
}
//UnicodeCategory
/**
* This class implements an {@link Lexicon.Alphabet Alphabet
} containing the characters in a Unicode general category.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class UnicodeCategory extends Alphabet {
/**
* The byte representing the Unicode general category.
*/
private final byte category;
/**
* Constructs an Alphabet
containing the characters in a Unicode general category, and builds the NFA constructed from this Expression
. The class {@link Character} defines byte constants representing each of the Unicode general categories.
*
* @param category The byte representing the Unicode general category.
* @see Character
*/
public UnicodeCategory(byte category) {
this.category = category;
put(i = s(), this, f = s());
}
/**
* Indicates whether a character occurs in this Alphabet
.
*
* @param a the character whose status is requested.
* @return true
if a
occurs in this Alphabet
; false
otherwise.
*/
boolean contains(char a) {
return Character.getType(a) == category;
}
/**
* Creates a clone of this Alphabet
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Alphabet
.
*/
public Object clone() {
return new UnicodeCategory(category);
}
}
//Repetition
/**
* This class implements an {@link Lexicon.Expression Expression
} expressing the repetition of a regular language.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class Repetition extends Expression {
/**
* The operand Expression
.
*/
private final Expression e1;
/**
* The minimum number of times e1
is repeated.
*/
private final int min;
/**
* The maximum number of times e1
is repeated.
*/
private final int max;
/**
* Constructs an Expression
expressing the repetition of a regular language, and builds the NFA constructed from this Expression
. Large finite values for the minimum or maximum cause the NFA constructed from the operand Expression
to be copied many times, resulting in a space-inefficient NFA.
*
* @param e1 the operand Expression
.
* @param min the minimum number of times e1
is repeated. If negative, it is assumed to be zero.
* @param max the maximum number of times e1
is repeated. If negative, it is assumed to be infinity.
*/
public Repetition(Expression e1, int min, int max) {
this.e1 = e1 = (Expression)e1.clone();
this.min = min = Math.max(min, 0);
this.max = max;
i = (min > 0) ? e1.i : s();
f = (min > 0) ? e1.f : i;
if (min == 0 && max < 0) {
put(i, null, e1.i);
put(e1.f, null, i);
}
else {
for (int k = 2; k <= min; k++) {
e1 = (Expression)e1.clone();
put(f, null, e1.i);
f = e1.f;
}
if (max > min) {
Integer tail = f;
put(tail, null, f = s());
for (int k = min+1; k <= max; k++) {
if (k > 1) e1 = (Expression)e1.clone();
put(tail, null, e1.i);
put(tail = e1.f, null, f);
}
}
else if (max < 0) put(f, null, e1.i);
}
}
/**
* Creates a clone of this Expression
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Expression
.
*/
public Object clone() {
return new Repetition(e1, min, max);
}
}
//Concatenation
/**
* This class implements an {@link Lexicon.Expression Expression
} expressing the concatenation of two regular languages.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class Concatenation extends Expression {
/**
* The left operand Expression
.
*/
private final Expression e1;
/**
* The right operand Expression
.
*/
private final Expression e2;
/**
* Constructs an Expression
expressing the concatenation of two regular languages, and builds the NFA constructed from this Expression
.
*
* @param e1 the left operand Expression
.
* @param e2 the right operand Expression
.
*/
public Concatenation(Expression e1, Expression e2) {
this.e1 = e1 = (Expression)e1.clone();
this.e2 = e2 = (Expression)e2.clone();
i = e1.i;
f = e2.f;
put(e1.f, null, e2.i);
}
/**
* Creates a clone of this Expression
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Expression
.
*/
public Object clone() {
return new Concatenation(e1, e2);
}
}
//Singleton
/**
* This class implements an {@link Lexicon.Expression Expression
} expressing a singleton language.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class Singleton extends Expression {
/**
* The string whose singleton language is expressed.
*/
private final String x;
/**
* Constructs an Expression
expressing a singleton language, and builds the NFA constructed from this Expression
.
*
* @param x the string whose singleton language is expressed.
*/
public Singleton(String x) {
this.x = x;
f = i = s();
for (char c : x.toCharArray())
new Match(f, c, f = s());
}
/**
* Creates a clone of this Expression
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Expression
.
*/
public Object clone() {
return new Singleton(x);
}
}
//Union
/**
* This class implements an {@link Lexicon.Expression Expression
} expressing the union of two regular languages.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public static class Union extends Expression {
/**
* The left operand Expression
.
*/
private final Expression e1;
/**
* The right operand Expression
.
*/
private final Expression e2;
/**
* Constructs an Expression
expressing the union of two regular languages, and builds the NFA constructed from this Expression
.
*
* @param e1 the left operand Expression
.
* @param e2 the right operand Expression
.
*/
public Union(Expression e1, Expression e2) {
this.e1 = e1 = (Expression)e1.clone();
this.e2 = e2 = (Expression)e2.clone();
i = s();
f = s();
put(i, null, e1.i); put(e1.f, null, f);
put(i, null, e2.i); put(e2.f, null, f);
}
/**
* Creates a clone of this Expression
, and replicates the NFA constructed from this Expression
.
*
* @return a clone of this Expression
.
*/
public Object clone() {
return new Union(e1, e2);
}
}
//expression(ere)
/**
* Creates an Expression
by interpreting a POSIX extended regular expression (ERE), as used in egrep. The syntax and semantics for EREs is formally specified by the ERE Grammar
. Provides a convenient method for constructing an Expression
, at the cost of an LR(1) parse. Implementations seeking maximum speed should avoid this method and use explicit Expression
subclass constructors; for example,
* new Union(new NonMatch("0"), new Singleton("foo"))
* instead of
* expression("[^0]|foo")
*
* @param ere the POSIX extended regular expression (ERE) to interpret.
* @return the Expression
constructed by interpreting ere
.
* @throws Lexicon.Exception if an ERE syntax error occurs.
*/
public static Expression expression(String ere) throws Exception {
return ERE.expression(ere);
}
//E
/**
* The mapping representing this Lexicon
. A terminal is mapped to the initial state of the NFA constructed from the associated Expression
.
*/
private final Map E;
/**
* Puts a terminal and associated Expression
into this Lexicon
. The Expression
supersedes any previously associated with the terminal.
*
* @param a the terminal to add to this Lexicon
.
* @param e the Expression
associated with terminal a
. When grabbing, the language expressed by e
matches a
.
*/
public void put(Object a, Expression e) {
E.put(a, e);
I.clear();
F.clear();
}
/**
* Indicates whether a symbol is a terminal in this Lexicon
.
*
* @param a the symbol whose status is requested.
* @return true
if a
is a terminal in this Lexicon
; false
otherwise.
*/
boolean terminal(Object a) {
return E.containsKey(a);
}
//Lexicon()
/**
* The terminal matched by the character at the end of a source stream.
* @since 1.1, renames END_OF_SOURCE
in version 1.0.
*/
protected static final Object $ = new String("$");
/**
* The Alphabet
containing the character at the end of a source stream.
*/
private static final Expression $_EXPRESSION = new Match((char)-1);
/**
* Constructs an empty Lexicon
.
*/
protected Lexicon() {
E = new HashMap(500);
I = new Set(-200);
F = new HashMap(500);
put($, $_EXPRESSION);
}
/**
* Constructs a Lexicon
that is a shallow copy of lexicon
. The fields of the new Lexicon
refer to the same elements as those in lexicon
.
*
*
* @param lexicon the Lexicon
to copy.
*/
Lexicon(Lexicon lexicon) {/*debug*/
debug = lexicon.debug;/*off*/
E = lexicon.E;
I = lexicon.I;
F = lexicon.F;
}
//Lexicon.initial
/**
* Returns the initial states of the lexical NFA.
*
* @return {@link #I}, computing it and {@link #F} if there is a need to compute the current initial states and final states.
*/
private Set initial() {
if (I.isEmpty()) {
for (Object a : E.keySet()) {
Expression e = E.get(a);
I.add(e.i);
F.put(e.f, a);
}
closure(I);
}
return I;
}
//accept
/**
* Computes the current final state, if any, in the lexical NFA.
*
* @param S the current states.
* @return the maximum final state in S
. Returns null
if S
contains no final states.
*/
private Integer accept(Set S) {
Integer
f = null;
for (Integer s : S)
if (F.containsKey(s))
if (f == null || f < s) f = s;
return f;
}
/**
* This class implements an {@link Lexicon.Exception Exception
}.
*
* @version 1.3
* @author © 1999-2009 Craig A. Rich <carich@csupomona.edu >
*/
public class Exception extends java.lang.Exception {
/**
* The extended error message.
*/
private StringBuffer message;
/**
* Constructs an Exception
with a message.
*
* @param message the error message.
*/
public Exception(String message) {
super(message);
}
/**
* Returns the error message.
*
* @return the error message.
*/
public String getMessage() {
return (message == null) ? super.getMessage() : message.toString();
}
/**
* Extends the error message in this Exception
. The extended message includes the line number, message and source characters following the error.
*
* @param source the source character stream.
* @return this Exception
with an extended message.
*/
Exception extend(LineNumberReader source) {
if (message == null) message = new StringBuffer(132);
else message.setLength(0);
message.append("line ");
message.append(source.getLineNumber()+1);
message.append(": ");
message.append(super.getMessage());
message.append(System.getProperty("line.separator"));
message.append("...");
message.append(word());
try {
String rest = source.readLine();
if (rest != null) message.append(rest);
}
catch (IOException exception) {}
message.append(System.getProperty("line.separator"));
message.append(" ^");
return this;
}
}
//Lexicon.grab
/**
* The states through which the lexical NFA transitions.
*/
private final Set[] R = (Set[])new Set>[]{new Set(-200), new Set(-200)};
/**
* The StringBuffer
containing the word most recently grabbed.
*/
private final StringBuffer w = new StringBuffer(4000);
/**
* Grabs a terminal from a source character stream using this Lexicon
. The variable returned by {@link #word()} is set to the longest nonempty prefix of the remaining source characters matching an Expression
in this Lexicon
. If no nonempty prefix matches an Expression
, a Lexicon.Exception
is thrown. If the longest matching prefix matches more than one Expression
, the terminal associated with the Expression
most recently constructed is returned. Blocks until a character is available, an I/O error occurs, or the end of the source stream is reached.
*
* @param source the source character stream.
* @return the terminal grabbed from source
.
* @throws Lexicon.Exception if an I/O or lexical error occurs.
*/
protected Object grab(LineNumberReader source) throws Exception {
Set S = initial();
w.setLength(0);
int wLength = 0;
Object b = null;
try {
source.mark(w.capacity());
do {
int a = source.read();
S = closure(transition(S, (char)a, R[w.length() % 2]));
if (S.isEmpty()) break;
if (a != -1) w.append((char)a); else w.append($);
Integer f = accept(S);
if (f != null) {
wLength = w.length();
b = F.get(f);
source.mark(w.capacity());
}
} while (b != $);
w.setLength(wLength);
source.reset();
}
catch (IOException exception) {
throw new Exception(exception.getMessage());
}
if (wLength == 0) throw new Exception("lexical error").extend(source);
return b;
}
/**
* Returns the word most recently grabbed using this Lexicon
.
*
* @return the word most recently grabbed by {@link #grab(java.io.LineNumberReader) grab(source)
}.
*/
protected String word() {
return w.substring(0);
}
//Lexicon.interpret
/**
* Repeatedly invokes {@link #grab(java.io.LineNumberReader) grab(source)
} until the end of the source stream reached. Blocks until a character is available, or an I/O error occurs. This method is overridden by Grammar
and its parser subclasses, so it is only invoked when this Lexicon
has not been extended into a Grammar
or parser.
*
* @param source the source character stream.
* @return the ParseTree
constructed by interpreting source
. A Lexicon
always returns null.
* @throws Lexicon.Exception if an I/O or lexical error occurs.
*/
Object interpret(LineNumberReader source) throws Exception {/*debug*/
if ((debug & TERMINALS) > 0) System.out.println(
"----terminals\n\t" + E.keySet().toString().replaceFirst("\\[", "{").replaceAll(", ", " ").replaceFirst("\\]$", "}\n----------"));/*off*/
for (Object a; (a = grab(source)) != $;)/*debug*/
if ((debug & LEXICAL) > 0) System.out.println(
a + (!a.equals(word()) ? " " + word() : ""))/*off*/
;
return null;
}
/**
* Interprets a source character stream using this Lexicon
.
*
* @param source the source character stream.
* @return the ParseTree
constructed by interpreting source
.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret(Reader source) throws Exception {
return interpret(new LineNumberReader(source));
}
/**
* Interprets a source string using this Lexicon
.
*
* @param source the source string.
* @return the ParseTree
constructed by interpreting source
.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret(String source) throws Exception {
return interpret(new StringReader(source));
}
/**
* Interprets a source byte stream using this Lexicon
.
*
* @param source the source byte stream.
* @return the ParseTree
constructed by interpreting source
.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret(InputStream source) throws Exception {
return interpret(new InputStreamReader(source));
}
/**
* Interprets the standard input stream using this Lexicon
.
*
* @return the ParseTree
constructed by interpreting the standard input stream.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret() throws Exception {
return interpret(System.in);
}
/**
* Interprets a source file using this Lexicon
.
*
* @param source the source file.
* @return the ParseTree
constructed by interpreting source
.
* @throws FileNotFoundException if the source file cannot be found.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret(File source) throws FileNotFoundException, Exception {
return interpret(new FileReader(source));
}
/**
* Interprets a source pipe using this Lexicon
.
*
* @param source the source pipe.
* @return the ParseTree
constructed by interpreting source
.
* @throws IOException if the source pipe cannot be connected.
* @throws Lexicon.Exception if an I/O, lexical, syntax or semantic error occurs.
*/
public Object interpret(PipedWriter source) throws IOException, Exception {
return interpret(new PipedReader(source));
}
//Lexicon.interpret(arguments)
/**
* The debug switches, initially zero. The following bits enable debugging to standard output:
*
* 0x01
= TERMINALS
* Print the set of terminals before lexical analysis
* 0x02
= LEXICAL
* Print terminals and associated words grabbed during lexical analysis
* 0x04
= FIRST_FOLLOW
* Print first and follow sets precomputed during syntax analysis
* 0x08
= SYNTAX
* Print parsing decisions made during syntax analysis
* 0x10
= CONFLICT
* Print parsing conflicts encountered during syntax analysis
* 0x20
= PARSE_TREE
* Print each ParseTree
produced by syntax analysis
*
* @since 1.1
*/
protected int debug = 0;
/**
* {@link #debug debug
} switch constant enabling printing the set of terminals before lexical analysis.
* @since 1.1
*/
protected static final int TERMINALS = 0x01;
/**
* {@link #debug debug
} switch constant enabling printing terminals and associated words grabbed during lexical analysis.
* @since 1.1
*/
protected static final int LEXICAL = 0x02;
/**
* {@link #debug debug
} switch constant enabling all debugging.
* @since 1.1
*/
protected static final int VERBOSE = 0xFF;
/**
* Lexical analysis by command-line arguments using this Lexicon
. The first I/O or lexical error that occurs during lexical analysis is printed to the standard error stream.
*
* @param arguments the command-line arguments controlling the interpreter.
*
* The following arguments may appear zero or more times, are processed in order, and have the following effects:
*
* -t
, --terminals
* Print the set of terminals in this Lexicon
before subsequent lexical analyses.
* -l
, --lexical
* Print terminals in this Lexicon
grabbed during subsequent lexical analyses.
* -v
, --verbose
* Print maximum debugging. Equivalent to -tl
.
* -
* Lexically analyze the standard input stream using this Lexicon
.
* filename
* Lexically analyze source file filename
using this Lexicon
.
*
* If no filename
arguments are given, the standard input stream is lexically analyzed.
*
*/
public void interpret(String[] arguments) {
boolean sourceSpecified = false;
Getopt options = new Getopt(getClass().getName(), arguments,
"-tlv", new LongOpt[]{
new LongOpt("terminals", 0, null, 't'),
new LongOpt("lexical", 0, null, 'l'),
new LongOpt("verbose", 0, null, 'v'),
}
);
for (int option; (option = options.getopt()) != -1;)
switch (option) {
case 't': debug |= TERMINALS; break;
case 'l': debug |= LEXICAL; break;
case 'v': debug |= VERBOSE; break;
case 1: String argument = options.getOptarg();
try {
sourceSpecified = true;
if (argument.equals("-"))
interpret();
else
interpret(new FileReader(argument));
}
catch (java.lang.Exception exception) {
System.err.println(exception);
}
}
if (!sourceSpecified) try {
interpret();
}
catch (java.lang.Exception exception) {
System.err.println(exception);
}
}
}