bundles/org.apache.jasper.glassfish/src/org/apache/jasper/util/SystemLogHandler.java
protected PrintStream findStream() {
        PrintStream ps = (PrintStream) streams.get();
        if (ps == null) {
            ps = wrapped;
        }
        return ps;
    }
protected PrintStream findStream() {
        PrintStream ps = (PrintStream) streams.get();
        if (ps == null) {
            ps = wrapped;
        }
        return ps;
    }
Find PrintStream to which the output must be written to.