SimpleLog.java
/*
* Copyright 2001-2004 The Apache Software Foundation.
*
* 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.apache.commons.logging.impl;
import java.io.InputStream;
import java.io.Serializable;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Properties;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogConfigurationException;
/**
* <p>
* Simple implementation of Log that sends all enabled log messages, for all
* defined loggers, to System.err. The following system properties are supported
* to configure the behavior of this logger:
*
* <ul>
* <li><code>org.apache.commons.logging.simplelog.defaultlog</code> - Default
* logging detail level for all instances of SimpleLog. Must be one of ("trace",
* "debug", "info", "warn", "error", or "fatal"). If not specified, defaults to
* "info".</li>
* <li><code>org.apache.commons.logging.simplelog.log.xxxxx</code> - Logging
* detail level for a SimpleLog instance named "xxxxx". Must be one of ("trace",
* "debug", "info", "warn", "error", or "fatal"). If not specified, the default
* logging detail level is used.</li>
* <li><code>org.apache.commons.logging.simplelog.showlogname</code> - Set to
* <code>true</code> if you want the Log instance name to be included in output
* messages. Defaults to <code>false</code>.</li>
* <li><code>org.apache.commons.logging.simplelog.showShortLogname</code> - Set
* to <code>true</code> if you want the last component of the name to be
* included in output messages. Defaults to <code>true</code>.</li>
* <li><code>org.apache.commons.logging.simplelog.showdatetime</code> - Set to
* <code>true</code> if you want the current date and time to be included in
* output messages. Default is <code>false</code>.</li>
* <li><code>org.apache.commons.logging.simplelog.dateTimeFormat</code> - The
* date and time format to be used in the output messages. The pattern
* describing the date and time format is the same that is used in
* <code>java.text.SimpleDateFormat</code>. If the format is not specified or is
* invalid, the default format is used. The default format is
* <code>yyyy/MM/dd HH:mm:ss:SSS zzz</code>.</li>
* </ul>
*
* <p>
* In addition to looking for system properties with the names specified above,
* this implementation also checks for a class loader resource named
* <code>"simplelog.properties"</code>, and includes any matching definitions
* from this resource (if it exists).
*
*
* @author <a href="mailto:sanders@apache.org">Scott Sanders</a>
* @author Rod Waldhoff
* @author Robert Burrell Donkin
*
* @version $Id: SimpleLog.java,v 1.21 2004/06/06 20:47:56 rdonkin Exp $
*/
public class SimpleLog implements Log, Serializable {
private static final long serialVersionUID = 136942970684951178L;
// ------------------------------------------------------- Class Attributes
/** All system properties used by <code>SimpleLog</code> start with this */
static protected final String systemPrefix = "org.apache.commons.logging.simplelog.";
/** Properties loaded from simplelog.properties */
static protected final Properties simpleLogProps = new Properties();
/** The default format to use when formatting dates */
static protected final String DEFAULT_DATE_TIME_FORMAT = "yyyy/MM/dd HH:mm:ss:SSS zzz";
/** Include the instance name in the log message? */
static protected boolean showLogName = false;
/**
* Include the short name ( last component ) of the logger in the log message.
* Defaults to true - otherwise we'll be lost in a flood of messages without
* knowing who sends them.
*/
static protected boolean showShortName = true;
/** Include the current time in the log message */
static protected boolean showDateTime = false;
/** The date and time format to use in the log message */
static protected String dateTimeFormat = DEFAULT_DATE_TIME_FORMAT;
/** Used to format times */
static protected DateFormat dateFormatter = null;
// ---------------------------------------------------- Log Level Constants
/** "Trace" level logging. */
public static final int LOG_LEVEL_TRACE = 1;
/** "Debug" level logging. */
public static final int LOG_LEVEL_DEBUG = 2;
/** "Info" level logging. */
public static final int LOG_LEVEL_INFO = 3;
/** "Warn" level logging. */
public static final int LOG_LEVEL_WARN = 4;
/** "Error" level logging. */
public static final int LOG_LEVEL_ERROR = 5;
/** "Fatal" level logging. */
public static final int LOG_LEVEL_FATAL = 6;
/** Enable all logging levels */
public static final int LOG_LEVEL_ALL = (LOG_LEVEL_TRACE - 1);
/** Enable no logging levels */
public static final int LOG_LEVEL_OFF = (LOG_LEVEL_FATAL + 1);
// ------------------------------------------------------------ Initializer
private static String getStringProperty(String name) {
String prop = null;
try {
prop = System.getProperty(name);
} catch (SecurityException e) {
; // Ignore
}
return (prop == null) ? simpleLogProps.getProperty(name) : prop;
}
private static String getStringProperty(String name, String dephault) {
String prop = getStringProperty(name);
return (prop == null) ? dephault : prop;
}
private static boolean getBooleanProperty(String name, boolean dephault) {
String prop = getStringProperty(name);
return (prop == null) ? dephault : "true".equalsIgnoreCase(prop);
}
// Initialize class attributes.
// Load properties file, if found.
// Override with system properties.
static {
// Add props from the resource simplelog.properties
InputStream in = getResourceAsStream("simplelog.properties");
if (null != in) {
try {
simpleLogProps.load(in);
} catch (java.io.IOException e) {
// ignored
} finally {
try {
in.close();
} catch (java.io.IOException e) {
// ignored
}
}
}
showLogName = getBooleanProperty(systemPrefix + "showlogname", showLogName);
showShortName = getBooleanProperty(systemPrefix + "showShortLogname", showShortName);
showDateTime = getBooleanProperty(systemPrefix + "showdatetime", showDateTime);
if (showDateTime) {
dateTimeFormat = getStringProperty(systemPrefix + "dateTimeFormat", dateTimeFormat);
try {
dateFormatter = new SimpleDateFormat(dateTimeFormat);
} catch (IllegalArgumentException e) {
// If the format pattern is invalid - use the default format
dateTimeFormat = DEFAULT_DATE_TIME_FORMAT;
dateFormatter = new SimpleDateFormat(dateTimeFormat);
}
}
}
// ------------------------------------------------------------- Attributes
/** The name of this simple log instance */
protected String logName = null;
/** The current log level */
protected int currentLogLevel;
/** The short name of this simple log instance */
private String shortLogName = null;
// ------------------------------------------------------------ Constructor
/**
* Construct a simple log with given name.
*
* @param name
* log name
*/
public SimpleLog(String name) {
logName = name;
// Set initial log level
// Used to be: set default log level to ERROR
// IMHO it should be lower, but at least info ( costin ).
setLevel(SimpleLog.LOG_LEVEL_INFO);
// Set log level from properties
String lvl = getStringProperty(systemPrefix + "log." + logName);
int i = String.valueOf(name).lastIndexOf(".");
while (null == lvl && i > -1) {
name = name.substring(0, i);
lvl = getStringProperty(systemPrefix + "log." + name);
i = String.valueOf(name).lastIndexOf(".");
}
if (null == lvl) {
lvl = getStringProperty(systemPrefix + "defaultlog");
}
if ("all".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_ALL);
} else if ("trace".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_TRACE);
} else if ("debug".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_DEBUG);
} else if ("info".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_INFO);
} else if ("warn".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_WARN);
} else if ("error".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_ERROR);
} else if ("fatal".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_FATAL);
} else if ("off".equalsIgnoreCase(lvl)) {
setLevel(SimpleLog.LOG_LEVEL_OFF);
}
}
// -------------------------------------------------------- Properties
/**
* <p>
* Set logging level.
*
*
* @param currentLogLevel
* new logging level
*/
public void setLevel(int currentLogLevel) {
this.currentLogLevel = currentLogLevel;
}
/**
* <p>
* Get logging level.
*
*/
public int getLevel() {
return currentLogLevel;
}
// -------------------------------------------------------- Logging Methods
/**
* <p>
* Do the actual logging. This method assembles the message and then calls
* <code>write()</code> to cause it to be written.
*
*
* @param type
* One of the LOG_LEVEL_XXX constants defining the log level
* @param message
* The message itself (typically a String)
* @param t
* The exception whose stack trace should be logged
*/
protected void log(int type, Object message, Throwable t) {
// Use a string buffer for better performance
StringBuffer buf = new StringBuffer();
// Append date-time if so configured
if (showDateTime) {
buf.append(dateFormatter.format(new Date()));
buf.append(" ");
}
// Append a readable representation of the log level
switch (type) {
case SimpleLog.LOG_LEVEL_TRACE:
buf.append("[TRACE] ");
break;
case SimpleLog.LOG_LEVEL_DEBUG:
buf.append("[DEBUG] ");
break;
case SimpleLog.LOG_LEVEL_INFO:
buf.append("[INFO] ");
break;
case SimpleLog.LOG_LEVEL_WARN:
buf.append("[WARN] ");
break;
case SimpleLog.LOG_LEVEL_ERROR:
buf.append("[ERROR] ");
break;
case SimpleLog.LOG_LEVEL_FATAL:
buf.append("[FATAL] ");
break;
}
// Append the name of the log instance if so configured
if (showShortName) {
if (shortLogName == null) {
// Cut all but the last component of the name for both styles
shortLogName = logName.substring(logName.lastIndexOf(".") + 1);
shortLogName = shortLogName.substring(shortLogName.lastIndexOf("/") + 1);
}
buf.append(String.valueOf(shortLogName)).append(" - ");
} else if (showLogName) {
buf.append(String.valueOf(logName)).append(" - ");
}
// Append the message
buf.append(String.valueOf(message));
// Append stack trace if not null
if (t != null) {
buf.append(" <");
buf.append(t.toString());
buf.append(">");
java.io.StringWriter sw = new java.io.StringWriter(1024);
java.io.PrintWriter pw = new java.io.PrintWriter(sw);
t.printStackTrace(pw);
pw.close();
buf.append(sw.toString());
}
// Print to the appropriate destination
write(buf);
}
/**
* <p>
* Write the content of the message accumulated in the specified
* <code>StringBuffer</code> to the appropriate output destination. The
* default implementation writes to <code>System.err</code>.
*
*
* @param buffer
* A <code>StringBuffer</code> containing the accumulated text to be
* logged
*/
protected void write(StringBuffer buffer) {
System.err.println(buffer.toString());
}
/**
* Is the given log level currently enabled?
*
* @param logLevel
* is this level enabled?
*/
protected boolean isLevelEnabled(int logLevel) {
// log level are numerically ordered so can use simple numeric
// comparison
return (logLevel >= currentLogLevel);
}
// -------------------------------------------------------- Log Implementation
/**
* <p>
* Log a message with debug log level.
*
*/
public final void debug(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG)) {
log(SimpleLog.LOG_LEVEL_DEBUG, message, null);
}
}
/**
* <p>
* Log an error with debug log level.
*
*/
public final void debug(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG)) {
log(SimpleLog.LOG_LEVEL_DEBUG, message, t);
}
}
/**
* <p>
* Log a message with trace log level.
*
*/
public final void trace(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE)) {
log(SimpleLog.LOG_LEVEL_TRACE, message, null);
}
}
/**
* <p>
* Log an error with trace log level.
*
*/
public final void trace(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE)) {
log(SimpleLog.LOG_LEVEL_TRACE, message, t);
}
}
/**
* <p>
* Log a message with info log level.
*
*/
public final void info(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_INFO)) {
log(SimpleLog.LOG_LEVEL_INFO, message, null);
}
}
/**
* <p>
* Log an error with info log level.
*
*/
public final void info(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_INFO)) {
log(SimpleLog.LOG_LEVEL_INFO, message, t);
}
}
/**
* <p>
* Log a message with warn log level.
*
*/
public final void warn(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_WARN)) {
log(SimpleLog.LOG_LEVEL_WARN, message, null);
}
}
/**
* <p>
* Log an error with warn log level.
*
*/
public final void warn(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_WARN)) {
log(SimpleLog.LOG_LEVEL_WARN, message, t);
}
}
/**
* <p>
* Log a message with error log level.
*
*/
public final void error(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR)) {
log(SimpleLog.LOG_LEVEL_ERROR, message, null);
}
}
/**
* <p>
* Log an error with error log level.
*
*/
public final void error(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR)) {
log(SimpleLog.LOG_LEVEL_ERROR, message, t);
}
}
/**
* <p>
* Log a message with fatal log level.
*
*/
public final void fatal(Object message) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL)) {
log(SimpleLog.LOG_LEVEL_FATAL, message, null);
}
}
/**
* <p>
* Log an error with fatal log level.
*
*/
public final void fatal(Object message, Throwable t) {
if (isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL)) {
log(SimpleLog.LOG_LEVEL_FATAL, message, t);
}
}
/**
* <p>
* Are debug messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isDebugEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_DEBUG);
}
/**
* <p>
* Are error messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isErrorEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_ERROR);
}
/**
* <p>
* Are fatal messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isFatalEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_FATAL);
}
/**
* <p>
* Are info messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isInfoEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_INFO);
}
/**
* <p>
* Are trace messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isTraceEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_TRACE);
}
/**
* <p>
* Are warn messages currently enabled?
*
*
* <p>
* This allows expensive operations such as <code>String</code> concatenation
* to be avoided when the message will be ignored by the logger.
*
*/
public final boolean isWarnEnabled() {
return isLevelEnabled(SimpleLog.LOG_LEVEL_WARN);
}
/**
* Return the thread context class loader if available. Otherwise return null.
*
* The thread context class loader is available for JDK 1.2 or later, if
* certain security conditions are met.
*
* @exception LogConfigurationException
* if a suitable class loader cannot be identified.
*/
private static ClassLoader getContextClassLoader() {
ClassLoader classLoader = null;
if (classLoader == null) {
try {
// Are we running on a JDK 1.2 or later system?
Method method = Thread.class.getMethod("getContextClassLoader");
// Get the thread context class loader (if there is one)
try {
classLoader = (ClassLoader) method.invoke(Thread.currentThread());
} catch (IllegalAccessException e) {
; // ignore
} catch (InvocationTargetException e) {
/**
* InvocationTargetException is thrown by 'invoke' when the method
* being invoked (getContextClassLoader) throws an exception.
*
* getContextClassLoader() throws SecurityException when the context
* class loader isn't an ancestor of the calling class's class loader,
* or if security permissions are restricted.
*
* In the first case (not related), we want to ignore and keep going.
* We cannot help but also ignore the second with the logic below, but
* other calls elsewhere (to obtain a class loader) will trigger this
* exception where we can make a distinction.
*/
if (e.getTargetException() instanceof SecurityException) {
; // ignore
} else {
// Capture 'e.getTargetException()' exception for details
// alternate: log 'e.getTargetException()', and pass back 'e'.
throw new LogConfigurationException("Unexpected InvocationTargetException", e.getTargetException());
}
}
} catch (NoSuchMethodException e) {
// Assume we are running on JDK 1.1
; // ignore
}
}
if (classLoader == null) {
classLoader = SimpleLog.class.getClassLoader();
}
// Return the selected class loader
return classLoader;
}
private static InputStream getResourceAsStream(final String name) {
return AccessController.doPrivileged((PrivilegedAction<InputStream>) () -> {
ClassLoader threadCL = getContextClassLoader();
if (threadCL != null) {
return threadCL.getResourceAsStream(name);
} else {
return ClassLoader.getSystemResourceAsStream(name);
}
});
}
}