SerializeComputations [1032124]

< > BotCompany Repo | #1032124 // SerializeComputations

JavaX fragment (include) [tags: use-pretranspiled]

sclass SerializeComputations<A, B> {
  Map<A, Var<OKOrError<B>>> calculating = syncMap();
  new MultiSetMap<A, Thread> waitingFor;
  
  B get(A a, IF1<A, B> f) {
    ret get(a, () -> f.get(a));
  }

  B get(A a, IF0<B> f) {
    bool meCalc;
    Var<OKOrError<B>> var;
    synchronized {
      var = calculating.get(a);
      meCalc = var == null;
      
      if (meCalc) {
        var = new Var;
        calculating.put(a, var);
      } else
        waitingFor.put(a, currentThread());
    }
    
    if (meCalc) {
      OKOrError<B> b = okOrError(() -> f!);
      var.set(b);
      ret b.getMandatory();
    } else {
      try {
        waitUntilNotNull(var);
        ret var->getMandatory();
      } finally {
        synchronized {
          waitingFor.remove(a, currentThread());
          if (!waitingFor.containsKey(a))
            calculating.remove(a);
        }
      }
    }
  }
}

Author comment

Began life as a copy of #1032122

Travelled to 4 computer(s): bhatertpkbcr, ekrmjmnbrukm, mqqgnosmbjvj, pyentgdyhuwx

Snippet ID:

#1032124

Snippet name:

SerializeComputations

Eternal ID of this version:

#1032124/11

Text MD5:

dc0dfda23739f460c10dc6f43fd0c864

Transpilation MD5:

01c17d6a75ebecebb251938a01470071

Author:

stefan

Category:

javax / multi-threading

Type:

JavaX fragment (include)

Public (visible to everyone):

Yes

Archived (hidden from active list):

Created/modified:

2021-11-01 23:22:20

Source code size:

930 bytes / 40 lines

Pitched / IR pitched:

No / No

Views / Downloads:

421 / 684

Version history:

10 change(s)

Referenced in:

[show references]

1	sclass SerializeComputations<A, B> {
2	Map<A, Var<OKOrError<B>>> calculating = syncMap();
3	new MultiSetMap<A, Thread> waitingFor;
4
5	B get(A a, IF1<A, B> f) {
6	ret get(a, () -> f.get(a));
7	}
8
9	B get(A a, IF0<B> f) {
10	bool meCalc;
11	Var<OKOrError<B>> var;
12	synchronized {
13	var = calculating.get(a);
14	meCalc = var == null;
15
16	if (meCalc) {
17	var = new Var;
18	calculating.put(a, var);
19	} else
20	waitingFor.put(a, currentThread());
21	}
22
23	if (meCalc) {
24	OKOrError<B> b = okOrError(() -> f!);
25	var.set(b);
26	ret b.getMandatory();
27	} else {
28	try {
29	waitUntilNotNull(var);
30	ret var->getMandatory();
31	} finally {
32	synchronized {
33	waitingFor.remove(a, currentThread());
34	if (!waitingFor.containsKey(a))
35	calculating.remove(a);
36	}
37	}
38	}
39	}
40	}