org.jboss.logmanager.handlers.OutputStreamHandler Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of jboss-logmanager Show documentation
An implementation of java.util.logging.LogManager
The newest version!
/*
 * JBoss, Home of Professional Open Source.
 *
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.jboss.logmanager.handlers;

import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.nio.charset.Charset;
import java.util.logging.ErrorManager;
import java.util.logging.Formatter;

import org.jboss.logmanager.formatters.Formatters;

/**
 * An output stream handler which supports any {@code OutputStream}, using the specified encoding. If no encoding is
 * specified, the platform default is used.
 */
public class OutputStreamHandler extends WriterHandler {

    private OutputStream outputStream;

    /**
     * Construct a new instance with no formatter.
     */
    public OutputStreamHandler() {
        setFormatter(Formatters.nullFormatter());
    }

    /**
     * Construct a new instance.
     *
     * @param formatter the formatter to use
     */
    public OutputStreamHandler(final Formatter formatter) {
        setFormatter(formatter);
    }

    /**
     * Construct a new instance.
     *
     * @param outputStream the output stream to use
     * @param formatter    the formatter to use
     */
    public OutputStreamHandler(final OutputStream outputStream, final Formatter formatter) {
        setFormatter(formatter);
        setOutputStream(outputStream);
    }

    @Override
    protected void setCharsetPrivate(Charset charset) throws SecurityException {
        // superclass checks access
        lock.lock();
        try {
            super.setCharsetPrivate(charset);
            // we only want to change the writer, not the output stream
            final OutputStream outputStream = this.outputStream;
            if (outputStream != null) {
                super.setWriter(getNewWriter(outputStream));
            }
        } finally {
            lock.unlock();
        }
    }

    /** {@inheritDoc} Setting a writer will replace any target output stream. */
    public void setWriter(final Writer writer) {
        lock.lock();
        try {
            super.setWriter(writer);
            final OutputStream oldStream = this.outputStream;
            outputStream = null;
            safeFlush(oldStream);
            safeClose(oldStream);
        } finally {
            lock.unlock();
        }
    }

    /**
     * Set the output stream to write to. The output stream will then belong to this handler; when the handler is
     * closed or a new writer or output stream is set, this output stream will be closed.
     *
     * @param outputStream the new output stream or {@code null} for none
     */
    public void setOutputStream(final OutputStream outputStream) {
        if (outputStream == null) {
            // call ours, not the superclass one
            this.setWriter(null);
            return;
        }
        checkAccess();
        // Close the writer, then close the old stream, then establish the new stream with a new writer.
        try {
            lock.lock();
            try {
                final OutputStream oldStream = this.outputStream;
                // do not close the old stream if creating the writer fails
                final Writer writer = getNewWriter(outputStream);
                try {
                    this.outputStream = outputStream;
                    super.setWriter(writer);
                } finally {
                    safeFlush(oldStream);
                    safeClose(oldStream);
                }
            } finally {
                lock.unlock();
            }
        } catch (Exception e) {
            reportError("Error opening output stream", e, ErrorManager.OPEN_FAILURE);
            return;
        }
    }

    OutputStream getOutputStream() {
        assert lock.isHeldByCurrentThread();
        return outputStream;
    }

    private Writer getNewWriter(OutputStream newOutputStream) {
        if (newOutputStream == null)
            return null;
        final UninterruptibleOutputStream outputStream = new UninterruptibleOutputStream(
                new UncloseableOutputStream(newOutputStream));
        return new OutputStreamWriter(outputStream, getCharset());
    }
}