InputStreamMonitor.writeNext() wait() not in loop — vulnerable to spurious wakeups

[robstryker]

In InputStreamMonitor.writeNext(), the fLock.wait() call at line 189 is guarded by an if check:

synchronized(fLock) {
    // Queue could receive more input between last empty check and
    // lock acquire. See https://bugs.eclipse.org/550834
    if (fQueue.isEmpty()) {
        fLock.wait();
    }
}

Per the Java specification, Object.wait() can return spuriously — without a corresponding notify()/notifyAll(). The standard pattern is to use a while loop instead of if:

synchronized(fLock) {
    while (fQueue.isEmpty() && !fClosed) {
        fLock.wait();
    }
}

This ensures the condition is rechecked after any wakeup. The !fClosed guard also avoids waiting forever if the stream was closed while waiting.

Found via SpotBugs static analysis (WA_NOT_IN_LOOP).