test/jdk/java/lang/System/LoggerFinder/internal/BootstrapLogger/LogStream.java

/*
 * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

import java.io.ByteArrayOutputStream;
import java.io.OutputStream;
import java.io.PrintStream;

import jdk.internal.logger.BootstrapLogger;

/**
 * We use an instance of this class to check what the logging system has printed
 * on System.err.
 */
class LogStream extends OutputStream {

    static final PrintStream err = System.err;

    private final ByteArrayOutputStream BAOS = new ByteArrayOutputStream();

    LogStream() {
        super();
    }

    @Override
    public synchronized void write(int b) {
        BAOS.write(b);
        err.write(b);
    }

    String drain() {
        BootstrapLoggerUtils.awaitPending();
        synchronized (this) {
            String txt = BAOS.toString();
            BAOS.reset();
            return txt;
        }
    }
}