Name: rmT116609 Date: 09/02/2004


A DESCRIPTION OF THE PROBLEM :
There is an incoherence in the class DataOutputStream about the thread-safe status of the class :

The 2 following functions of the class java.io.DataOutputStream are doing about the same things, but one of them is thread-safe and the other one is not

    public synchronized void write(int b) throws IOException {
out.write(b);
incCount(1);
    }

    public final void writeBoolean(boolean v) throws IOException {
out.write(v ? 1 : 0);
incCount(1);
    }


The incCount() method copied below is CLEARLY NOT thread-safe :

    private void incCount(int value) {
        int temp = written + value;
        if (temp < 0) {
            temp = Integer.MAX_VALUE;
        }
        written = temp;
    }


Now, 2 possibilities :

- You assume that the class shouldn't be thread-safe, and then you don't need the synchronizations on none of the methods.

- You assume that the class should be thread-safe, and then all the write{Boolean, short, ...}() functions should be synchonized and there is actually a bug because they aren't.

REPRODUCIBILITY :
This bug can be reproduced always.
(Incident Review ID: 301238)
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