/*

 * Copyright (c) 2017, 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.IOException;

import java.io.PrintStream;

import java.lang.management.ManagementFactory;

import java.util.List;

import javax.management.MBeanServer;

import javax.management.ObjectName;

public class LoggingTest {

    static class TestStream extends PrintStream {

        final ByteArrayOutputStream bos = new ByteArrayOutputStream();

        private volatile boolean recording;

        public TestStream(PrintStream wrapped) {

            super(wrapped);

        }

        void startRecording() {

            recording = true;

        }

        void stopRecording() {

            recording = false;

        }

        @Override

        public void write(int b) {

            if (recording) {

                bos.write(b);

            }

            super.write(b);

        }

        @Override

        public void write(byte[] buf, int off, int len) {

            if (recording) {

                bos.write(buf, off, len);

            }

            super.write(buf, off, len);

        }

        @Override

        public void write(byte[] buf) throws IOException {

            if (recording) {

                bos.write(buf);

            }

            super.write(buf);

        }

    }

    public void run(TestStream ts) {

        // start recording traces and trigger creation of the platform

        // MBeanServer to produce some. This won't work if the platform

        // MBeanServer was already initialized - so it's important to

        // run this test in its own JVM.

        ts.startRecording();

        MBeanServer platform = ManagementFactory.getPlatformMBeanServer();

        ts.stopRecording();

        String printed = ts.bos.toString();

        ts.bos.reset();

        // Check that the Platform MBeanServer is emitting the expected

        // log traces. This can be a bit fragile because debug traces

        // could be changed without notice - in which case this test will

        // need to be updated.

        // For each registered MBean we expect to see three traces.

        // If the messages logged by the MBeanServer change then these checks

        // may need to be revisited.

        List<String> checkTraces =

                List.of("ObjectName = %s", "name = %s", "JMX.mbean.registered %s");

        for (ObjectName o : platform.queryNames(ObjectName.WILDCARD, null)) {

            String n = o.toString();

            System.out.println("Checking log for: " + n);

            for (String check : checkTraces) {

                String s = String.format(check, n);

                if (!printed.contains(s)) {

                    throw new RuntimeException("Trace not found: " + s);

                }

            }

        }

    }

}