Java tutorial
//======================================================================== //$Id: LogStream.java,v 1.3 2005/08/13 00:01:27 gregwilkins Exp $ //Copyright 2004 Mort Bay Consulting Pty. Ltd. //------------------------------------------------------------------------ //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 net.lightbody.bmp.proxy.jetty.log; import net.lightbody.bmp.proxy.jetty.util.ByteArrayOutputStream2; import org.apache.commons.logging.Log; import java.io.PrintStream; /** * Divert a PrintStream to commons logging. * The stderr and stdout streams can be diverted to logs named "stderr" and "stdout" using this * class. * */ public class LogStream extends PrintStream { public static class STDERR extends LogStream { STDERR() { super("STDERR ", LogFactory.getLog("stderr")); } } public static class STDOUT extends LogStream { STDOUT() { super("STDOUT ", LogFactory.getLog("stdout")); } } /*-------------------------------------------------------------------*/ final static PrintStream STDERR_STREAM = System.err; final static PrintStream STDOUT_STREAM = System.out; /* ------------------------------------------------------------ */ /** Log standard error stream. * If set to true, output to stderr will be directed to an instance * of LogStream and logged. Beware of log loops from logs that write to stderr. */ public static void setLogStdErr(boolean log) { if (log) { if (!(System.err instanceof LogStream)) System.setErr(new LogStream.STDERR()); } else System.setErr(STDERR_STREAM); } /* ------------------------------------------------------------ */ public static boolean getLogStdErr() { return System.err instanceof LogStream; } /* ------------------------------------------------------------ */ /** Log standard output stream. * If set to true, output to stdout will be directed to an instance * of LogStream and logged. Beware of log loops from logs that write to stdout. */ public static void setLogStdOut(boolean log) { if (log) { if (!(System.out instanceof LogStream)) System.setOut(new LogStream.STDOUT()); } else System.setOut(STDOUT_STREAM); } /* ------------------------------------------------------------ */ public static boolean getLogStdOut() { return System.out instanceof LogStream; } /* ------------------------------------------------------------ */ private String tag; private Log log; private ByteArrayOutputStream2 bout; /* */ public void flush() { super.flush(); if (bout.size() > 0) { String s = new String(bout.getBuf(), 0, bout.size()).trim(); if (s.length() > 0 && log != null) log.info(tag + ": " + s); } bout.reset(); } /** * @param out * @param autoflush */ public LogStream(String tag, Log log) { super(new ByteArrayOutputStream2(128), true); bout = (ByteArrayOutputStream2) this.out; this.tag = tag; this.log = log; } public void close() { flush(); super.close(); } public void println() { super.println(); flush(); } public void println(boolean arg0) { super.println(arg0); flush(); } public void println(char arg0) { super.println(arg0); flush(); } public void println(char[] arg0) { super.println(arg0); flush(); } public void println(double arg0) { super.println(arg0); flush(); } public void println(float arg0) { super.println(arg0); flush(); } public void println(int arg0) { super.println(arg0); flush(); } public void println(long arg0) { super.println(arg0); flush(); } public void println(Object arg0) { super.println(arg0); flush(); } public void println(String arg0) { super.println(arg0); flush(); } public void write(byte[] arg0, int arg1, int arg2) { super.write(arg0, arg1, arg2); flush(); } }