[Mulgara-svn] r1123 - trunk/src/jar/util/java/org/mulgara/util

[pag at mulgara.org]

Author: pag
Date: 2008-08-09 18:58:55 -0700 (Sat, 09 Aug 2008)
New Revision: 1123

Added:
   trunk/src/jar/util/java/org/mulgara/util/MortbayLogger.java
Log:
Implementation of a logger class for Mortbay libraries (specifically, Jetty) so we can control what goes where. Just a trivial redirection to a Log4J logger, with the ability to disable all logging.

Added: trunk/src/jar/util/java/org/mulgara/util/MortbayLogger.java
===================================================================
--- trunk/src/jar/util/java/org/mulgara/util/MortbayLogger.java	                        (rev 0)
+++ trunk/src/jar/util/java/org/mulgara/util/MortbayLogger.java	2008-08-10 01:58:55 UTC (rev 1123)
@@ -0,0 +1,186 @@
+/*
+ * The contents of this file are subject to the Open Software License
+ * Version 3.0 (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.opensource.org/licenses/osl-3.0.txt
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ */
+
+package org.mulgara.util;
+
+import org.mortbay.log.Logger;
+
+/**
+ * This class is used for managing logging by the Mortbay libraries.
+ * It can be set to send to the standard logging facilities, or set to ignore everything.
+ * @see org.mortbay.log.Logger
+ *
+ * @created Aug 6, 2008
+ * @author Paul Gearon
+ * @copyright &copy; 2008 <a href="http://www.topazproject.org/">The Topaz Project</a>
+ * @licence <a href="{@docRoot}/../../LICENCE.txt">Open Software License v3.0</a>
+ */
+public class MortbayLogger implements Logger {
+
+  /** The Log4J logger this class can proxy for. */
+  protected static org.apache.log4j.Logger log = org.apache.log4j.Logger.getLogger(MortbayLogger.class.getName());
+
+  /**
+   * The property that has to be set to this class in order for this class to be loaded
+   * as the logger for org.mortbay.* classes.
+   */ 
+  public static final String LOGGING_CLASS_PROPERTY = "org.mortbay.log.class";
+
+  /** This flag turns logging on and off. */
+  static boolean enabled = false;
+
+  /** This flag turns debug logging on and off. */
+  boolean debugEnabled = true;
+
+  /** The name of this object. */
+  private String name;
+
+
+  /**
+   * Sets all instances of this logger on and off.
+   * @param enabled when <code>false</code> this logger will not do anything.
+   */
+  public static void setEnabled(boolean enabled) {
+    MortbayLogger.enabled = enabled;
+  }
+
+
+  /**
+   * Returns the enabled state for all instances of this logging class.
+   * @return <code>true</code> if this class logs anything.
+   */
+  public static boolean isEnabled() {
+    return enabled;
+  }
+
+
+  /**
+   * Creates a logger with a default name.
+   */
+  public MortbayLogger() {
+    this.name = getClass().getName() + System.identityHashCode(this);
+  }
+
+
+  /**
+   * Creates a named logger.
+   * @param name The name for this logger.
+   */
+  public MortbayLogger(String name) {
+    this.name = name;
+  }
+
+
+  /**
+   * Logs a debug message and Throwable.
+   * @param msg The message to log.
+   * @param th The Throwable relevant to this log.
+   */
+  public void debug(String msg, Throwable th) {
+    if (enabled && debugEnabled) log.debug(msg, th);
+  }
+
+
+  /**
+   * Logs a debug message, and optionally up to 2 objects. These appear in the message
+   * replacing the first 2 instances of "{}" characters, if such characters exist.
+   * @param msg The message to log.
+   * @param arg0 Data to replace the first "{}" sequence in <var>msg</var>.
+   * @param arg1 Data to replace the second "{}" sequence in <var>msg</var>.
+   */
+  public void debug(String msg, Object arg0, Object arg1) {
+    if (enabled && debugEnabled) log.debug(format(msg, arg0, arg1));
+  }
+
+
+  /**
+   * Get an instance of a Logger for a given name.
+   * @param name The name of the logger to return. If <code>null</code> or empty
+   *        then the name of the current logger is used.
+   * @return A logger with the name from the <var>name</var> parameter, or the current logger
+   *         if no name was given.
+   */
+  public Logger getLogger(String name) {
+    if (name == null || name.equals("") || name.equals(this.name)) return this;
+    return new MortbayLogger(name);
+  }
+
+
+  /**
+   * Logs an info message, and optionally up to 2 objects. These appear in the message
+   * replacing the first 2 instances of "{}" characters, if such characters exist.
+   * @param msg The message to log.
+   * @param arg0 Data to replace the first "{}" sequence in <var>msg</var>.
+   * @param arg1 Data to replace the second "{}" sequence in <var>msg</var>.
+   */
+  public void info(String msg, Object arg0, Object arg1) {
+    if (enabled) log.info(format(msg, arg0, arg1));
+  }
+
+
+  /**
+   * Indicates if debug messages are logged.
+   * @return <code>true</code> if debug messages are acted on.
+   */
+  public boolean isDebugEnabled() {
+    return debugEnabled;
+  }
+
+
+  /**
+   * Set whether or not to log debug messages.
+   * @param enabled <code>true</code> if debug messages are to be acted on.
+   */
+  public void setDebugEnabled(boolean enabled) {
+    debugEnabled = enabled;
+  }
+
+
+  /**
+   * Logs a warning message and Throwable.
+   * @param msg The message to log.
+   * @param th The Throwable relevant to this log.
+   */
+  public void warn(String msg, Throwable th) {
+    if (enabled) log.warn(msg, th);
+  }
+
+
+  /**
+   * Logs a warning message, and optionally up to 2 objects. These appear in the message
+   * replacing the first 2 instances of "{}" characters, if such characters exist.
+   * @param msg The message to log.
+   * @param arg0 Data to replace the first "{}" sequence in <var>msg</var>.
+   * @param arg1 Data to replace the second "{}" sequence in <var>msg</var>.
+   */
+  public void warn(String msg, Object arg0, Object arg1) {
+    if (enabled) log.warn(format(msg, arg0, arg1));
+  }
+
+
+  /**
+   * Writes 2 objects into a string, replacing the instances of {} with the objects.
+   * @param msg The message with the two {} instances.
+   * @param arg0 The first object to print.
+   * @param arg1 The second object to print.
+   * @return The new string with the objects inserted.
+   */
+  private String format(String msg, Object arg0, Object arg1) {
+    // simple test to avoid the unlikely event of a buffer overrun
+    if (msg.contains("%s")) return msg + ": " + arg0 + " - " + arg1;
+    // only replace the first 2 instances - leave the rest alone
+    msg = msg.replaceFirst("\\{\\}", "%s").replaceFirst("\\{\\}", "%s");
+    String a0 = (arg0 == null) ? "-" : arg0.toString();
+    String a1 = (arg1 == null) ? "-" : arg1.toString();
+    return String.format(msg, a0, a1);
+  }
+}