6876135: Add PlatformLoggingMXBean to eliminate the dependency on JMX from logging
Summary: Added a new PlatformLoggingMXBean interface to extend PlatformManagedObject instead of LoggingMXBean
Reviewed-by: alanb
/*
* Copyright 2000-2007 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package java.util.logging;
import java.io.*;
import java.util.*;
import java.security.*;
import java.lang.ref.WeakReference;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.net.URL;
import sun.security.action.GetPropertyAction;
/**
* There is a single global LogManager object that is used to
* maintain a set of shared state about Loggers and log services.
* <p>
* This LogManager object:
* <ul>
* <li> Manages a hierarchical namespace of Logger objects. All
* named Loggers are stored in this namespace.
* <li> Manages a set of logging control properties. These are
* simple key-value pairs that can be used by Handlers and
* other logging objects to configure themselves.
* </ul>
* <p>
* The global LogManager object can be retrieved using LogManager.getLogManager().
* The LogManager object is created during class initialization and
* cannot subsequently be changed.
* <p>
* At startup the LogManager class is located using the
* java.util.logging.manager system property.
* <p>
* By default, the LogManager reads its initial configuration from
* a properties file "lib/logging.properties" in the JRE directory.
* If you edit that property file you can change the default logging
* configuration for all uses of that JRE.
* <p>
* In addition, the LogManager uses two optional system properties that
* allow more control over reading the initial configuration:
* <ul>
* <li>"java.util.logging.config.class"
* <li>"java.util.logging.config.file"
* </ul>
* These two properties may be set via the Preferences API, or as
* command line property definitions to the "java" command, or as
* system property definitions passed to JNI_CreateJavaVM.
* <p>
* If the "java.util.logging.config.class" property is set, then the
* property value is treated as a class name. The given class will be
* loaded, an object will be instantiated, and that object's constructor
* is responsible for reading in the initial configuration. (That object
* may use other system properties to control its configuration.) The
* alternate configuration class can use <tt>readConfiguration(InputStream)</tt>
* to define properties in the LogManager.
* <p>
* If "java.util.logging.config.class" property is <b>not</b> set,
* then the "java.util.logging.config.file" system property can be used
* to specify a properties file (in java.util.Properties format). The
* initial logging configuration will be read from this file.
* <p>
* If neither of these properties is defined then, as described
* above, the LogManager will read its initial configuration from
* a properties file "lib/logging.properties" in the JRE directory.
* <p>
* The properties for loggers and Handlers will have names starting
* with the dot-separated name for the handler or logger.
* <p>
* The global logging properties may include:
* <ul>
* <li>A property "handlers". This defines a whitespace or comma separated
* list of class names for handler classes to load and register as
* handlers on the root Logger (the Logger named ""). Each class
* name must be for a Handler class which has a default constructor.
* Note that these Handlers may be created lazily, when they are
* first used.
*
* <li>A property "<logger>.handlers". This defines a whitespace or
* comma separated list of class names for handlers classes to
* load and register as handlers to the specified logger. Each class
* name must be for a Handler class which has a default constructor.
* Note that these Handlers may be created lazily, when they are
* first used.
*
* <li>A property "<logger>.useParentHandlers". This defines a boolean
* value. By default every logger calls its parent in addition to
* handling the logging message itself, this often result in messages
* being handled by the root logger as well. When setting this property
* to false a Handler needs to be configured for this logger otherwise
* no logging messages are delivered.
*
* <li>A property "config". This property is intended to allow
* arbitrary configuration code to be run. The property defines a
* whitespace or comma separated list of class names. A new instance will be
* created for each named class. The default constructor of each class
* may execute arbitrary code to update the logging configuration, such as
* setting logger levels, adding handlers, adding filters, etc.
* </ul>
* <p>
* Note that all classes loaded during LogManager configuration are
* first searched on the system class path before any user class path.
* That includes the LogManager class, any config classes, and any
* handler classes.
* <p>
* Loggers are organized into a naming hierarchy based on their
* dot separated names. Thus "a.b.c" is a child of "a.b", but
* "a.b1" and a.b2" are peers.
* <p>
* All properties whose names end with ".level" are assumed to define
* log levels for Loggers. Thus "foo.level" defines a log level for
* the logger called "foo" and (recursively) for any of its children
* in the naming hierarchy. Log Levels are applied in the order they
* are defined in the properties file. Thus level settings for child
* nodes in the tree should come after settings for their parents.
* The property name ".level" can be used to set the level for the
* root of the tree.
* <p>
* All methods on the LogManager object are multi-thread safe.
*
* @since 1.4
*/
public class LogManager {
// The global LogManager object
private static LogManager manager;
private final static Handler[] emptyHandlers = { };
private Properties props = new Properties();
private PropertyChangeSupport changes
= new PropertyChangeSupport(LogManager.class);
private final static Level defaultLevel = Level.INFO;
// Table of known loggers. Maps names to Loggers.
private Hashtable<String,WeakReference<Logger>> loggers =
new Hashtable<String,WeakReference<Logger>>();
// Tree of known loggers
private LogNode root = new LogNode(null);
private Logger rootLogger;
// Have we done the primordial reading of the configuration file?
// (Must be done after a suitable amount of java.lang.System
// initialization has been done)
private volatile boolean readPrimordialConfiguration;
// Have we initialized global (root) handlers yet?
// This gets set to false in readConfiguration
private boolean initializedGlobalHandlers = true;
// True if JVM death is imminent and the exit hook has been called.
private boolean deathImminent;
static {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
String cname = null;
try {
cname = System.getProperty("java.util.logging.manager");
if (cname != null) {
try {
Class clz = ClassLoader.getSystemClassLoader().loadClass(cname);
manager = (LogManager) clz.newInstance();
} catch (ClassNotFoundException ex) {
Class clz = Thread.currentThread().getContextClassLoader().loadClass(cname);
manager = (LogManager) clz.newInstance();
}
}
} catch (Exception ex) {
System.err.println("Could not load Logmanager \"" + cname + "\"");
ex.printStackTrace();
}
if (manager == null) {
manager = new LogManager();
}
// Create and retain Logger for the root of the namespace.
manager.rootLogger = manager.new RootLogger();
manager.addLogger(manager.rootLogger);
// Adding the global Logger. Doing so in the Logger.<clinit>
// would deadlock with the LogManager.<clinit>.
Logger.global.setLogManager(manager);
manager.addLogger(Logger.global);
// We don't call readConfiguration() here, as we may be running
// very early in the JVM startup sequence. Instead readConfiguration
// will be called lazily in getLogManager().
return null;
}
});
}
// This private class is used as a shutdown hook.
// It does a "reset" to close all open handlers.
private class Cleaner extends Thread {
private Cleaner() {
/* Set context class loader to null in order to avoid
* keeping a strong reference to an application classloader.
*/
this.setContextClassLoader(null);
}
public void run() {
// This is to ensure the LogManager.<clinit> is completed
// before synchronized block. Otherwise deadlocks are possible.
LogManager mgr = manager;
// If the global handlers haven't been initialized yet, we
// don't want to initialize them just so we can close them!
synchronized (LogManager.this) {
// Note that death is imminent.
deathImminent = true;
initializedGlobalHandlers = true;
}
// Do a reset to close all active handlers.
reset();
}
}
/**
* Protected constructor. This is protected so that container applications
* (such as J2EE containers) can subclass the object. It is non-public as
* it is intended that there only be one LogManager object, whose value is
* retrieved by calling Logmanager.getLogManager.
*/
protected LogManager() {
// Add a shutdown hook to close the global handlers.
try {
Runtime.getRuntime().addShutdownHook(new Cleaner());
} catch (IllegalStateException e) {
// If the VM is already shutting down,
// We do not need to register shutdownHook.
}
}
/**
* Return the global LogManager object.
*/
public static LogManager getLogManager() {
if (manager != null) {
manager.readPrimordialConfiguration();
}
return manager;
}
private void readPrimordialConfiguration() {
if (!readPrimordialConfiguration) {
synchronized (this) {
if (!readPrimordialConfiguration) {
// If System.in/out/err are null, it's a good
// indication that we're still in the
// bootstrapping phase
if (System.out == null) {
return;
}
readPrimordialConfiguration = true;
try {
AccessController.doPrivileged(new PrivilegedExceptionAction<Object>() {
public Object run() throws Exception {
readConfiguration();
// Platform loggers begin to delegate to java.util.logging.Logger
sun.util.logging.PlatformLogger.redirectPlatformLoggers();
return null;
}
});
} catch (Exception ex) {
// System.err.println("Can't read logging configuration:");
// ex.printStackTrace();
}
}
}
}
}
/**
* Adds an event listener to be invoked when the logging
* properties are re-read. Adding multiple instances of
* the same event Listener results in multiple entries
* in the property event listener table.
*
* @param l event listener
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
* @exception NullPointerException if the PropertyChangeListener is null.
*/
public void addPropertyChangeListener(PropertyChangeListener l) throws SecurityException {
if (l == null) {
throw new NullPointerException();
}
checkAccess();
changes.addPropertyChangeListener(l);
}
/**
* Removes an event listener for property change events.
* If the same listener instance has been added to the listener table
* through multiple invocations of <CODE>addPropertyChangeListener</CODE>,
* then an equivalent number of
* <CODE>removePropertyChangeListener</CODE> invocations are required to remove
* all instances of that listener from the listener table.
* <P>
* Returns silently if the given listener is not found.
*
* @param l event listener (can be null)
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void removePropertyChangeListener(PropertyChangeListener l) throws SecurityException {
checkAccess();
changes.removePropertyChangeListener(l);
}
// Package-level method.
// Find or create a specified logger instance. If a logger has
// already been created with the given name it is returned.
// Otherwise a new logger instance is created and registered
// in the LogManager global namespace.
Logger demandLogger(String name) {
Logger result = getLogger(name);
if (result == null) {
result = new Logger(name, null);
addLogger(result);
result = getLogger(name);
}
return result;
}
// If logger.getUseParentHandlers() returns 'true' and any of the logger's
// parents have levels or handlers defined, make sure they are instantiated.
private void processParentHandlers(Logger logger, String name) {
int ix = 1;
for (;;) {
int ix2 = name.indexOf(".", ix);
if (ix2 < 0) {
break;
}
String pname = name.substring(0,ix2);
if (getProperty(pname+".level") != null ||
getProperty(pname+".handlers") != null) {
// This pname has a level/handlers definition.
// Make sure it exists.
demandLogger(pname);
}
ix = ix2+1;
}
}
// Add new per logger handlers.
// We need to raise privilege here. All our decisions will
// be made based on the logging configuration, which can
// only be modified by trusted code.
private void loadLoggerHandlers(final Logger logger, final String name,
final String handlersPropertyName) {
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
if (logger != rootLogger) {
boolean useParent = getBooleanProperty(name + ".useParentHandlers", true);
if (!useParent) {
logger.setUseParentHandlers(false);
}
}
String names[] = parseClassNames(handlersPropertyName);
for (int i = 0; i < names.length; i++) {
String word = names[i];
try {
Class clz = ClassLoader.getSystemClassLoader().loadClass(word);
Handler hdl = (Handler) clz.newInstance();
try {
// Check if there is a property defining the
// this handler's level.
String levs = getProperty(word + ".level");
if (levs != null) {
hdl.setLevel(Level.parse(levs));
}
} catch (Exception ex) {
System.err.println("Can't set level for " + word);
// Probably a bad level. Drop through.
}
// Add this Handler to the logger
logger.addHandler(hdl);
} catch (Exception ex) {
System.err.println("Can't load log handler \"" + word + "\"");
System.err.println("" + ex);
ex.printStackTrace();
}
}
return null;
}});
}
/**
* Add a named logger. This does nothing and returns false if a logger
* with the same name is already registered.
* <p>
* The Logger factory methods call this method to register each
* newly created Logger.
* <p>
* The application should retain its own reference to the Logger
* object to avoid it being garbage collected. The LogManager
* may only retain a weak reference.
*
* @param logger the new logger.
* @return true if the argument logger was registered successfully,
* false if a logger of that name already exists.
* @exception NullPointerException if the logger name is null.
*/
public synchronized boolean addLogger(Logger logger) {
final String name = logger.getName();
if (name == null) {
throw new NullPointerException();
}
WeakReference<Logger> ref = loggers.get(name);
if (ref != null) {
if (ref.get() == null) {
// Hashtable holds stale weak reference
// to a logger which has been GC-ed.
// Allow to register new one.
loggers.remove(name);
} else {
// We already have a registered logger with the given name.
return false;
}
}
// We're adding a new logger.
// Note that we are creating a weak reference here.
loggers.put(name, new WeakReference<Logger>(logger));
// Apply any initial level defined for the new logger.
Level level = getLevelProperty(name+".level", null);
if (level != null) {
doSetLevel(logger, level);
}
// Do we have a per logger handler too?
// Note: this will add a 200ms penalty
loadLoggerHandlers(logger, name, name+".handlers");
processParentHandlers(logger, name);
// Find the new node and its parent.
LogNode node = findNode(name);
node.loggerRef = new WeakReference<Logger>(logger);
Logger parent = null;
LogNode nodep = node.parent;
while (nodep != null) {
WeakReference<Logger> nodeRef = nodep.loggerRef;
if (nodeRef != null) {
parent = nodeRef.get();
if (parent != null) {
break;
}
}
nodep = nodep.parent;
}
if (parent != null) {
doSetParent(logger, parent);
}
// Walk over the children and tell them we are their new parent.
node.walkAndSetParent(logger);
return true;
}
// Private method to set a level on a logger.
// If necessary, we raise privilege before doing the call.
private static void doSetLevel(final Logger logger, final Level level) {
SecurityManager sm = System.getSecurityManager();
if (sm == null) {
// There is no security manager, so things are easy.
logger.setLevel(level);
return;
}
// There is a security manager. Raise privilege before
// calling setLevel.
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
logger.setLevel(level);
return null;
}});
}
// Private method to set a parent on a logger.
// If necessary, we raise privilege before doing the setParent call.
private static void doSetParent(final Logger logger, final Logger parent) {
SecurityManager sm = System.getSecurityManager();
if (sm == null) {
// There is no security manager, so things are easy.
logger.setParent(parent);
return;
}
// There is a security manager. Raise privilege before
// calling setParent.
AccessController.doPrivileged(new PrivilegedAction<Object>() {
public Object run() {
logger.setParent(parent);
return null;
}});
}
// Find a node in our tree of logger nodes.
// If necessary, create it.
private LogNode findNode(String name) {
if (name == null || name.equals("")) {
return root;
}
LogNode node = root;
while (name.length() > 0) {
int ix = name.indexOf(".");
String head;
if (ix > 0) {
head = name.substring(0,ix);
name = name.substring(ix+1);
} else {
head = name;
name = "";
}
if (node.children == null) {
node.children = new HashMap<String,LogNode>();
}
LogNode child = node.children.get(head);
if (child == null) {
child = new LogNode(node);
node.children.put(head, child);
}
node = child;
}
return node;
}
/**
* Method to find a named logger.
* <p>
* Note that since untrusted code may create loggers with
* arbitrary names this method should not be relied on to
* find Loggers for security sensitive logging.
* <p>
* @param name name of the logger
* @return matching logger or null if none is found
*/
public synchronized Logger getLogger(String name) {
WeakReference<Logger> ref = loggers.get(name);
if (ref == null) {
return null;
}
Logger logger = ref.get();
if (logger == null) {
// Hashtable holds stale weak reference
// to a logger which has been GC-ed.
loggers.remove(name);
}
return logger;
}
/**
* Get an enumeration of known logger names.
* <p>
* Note: Loggers may be added dynamically as new classes are loaded.
* This method only reports on the loggers that are currently registered.
* <p>
* @return enumeration of logger name strings
*/
public synchronized Enumeration<String> getLoggerNames() {
return loggers.keys();
}
/**
* Reinitialize the logging properties and reread the logging configuration.
* <p>
* The same rules are used for locating the configuration properties
* as are used at startup. So normally the logging properties will
* be re-read from the same file that was used at startup.
* <P>
* Any log level definitions in the new configuration file will be
* applied using Logger.setLevel(), if the target Logger exists.
* <p>
* A PropertyChangeEvent will be fired after the properties are read.
*
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
* @exception IOException if there are IO problems reading the configuration.
*/
public void readConfiguration() throws IOException, SecurityException {
checkAccess();
// if a configuration class is specified, load it and use it.
String cname = System.getProperty("java.util.logging.config.class");
if (cname != null) {
try {
// Instantiate the named class. It is its constructor's
// responsibility to initialize the logging configuration, by
// calling readConfiguration(InputStream) with a suitable stream.
try {
Class clz = ClassLoader.getSystemClassLoader().loadClass(cname);
clz.newInstance();
return;
} catch (ClassNotFoundException ex) {
Class clz = Thread.currentThread().getContextClassLoader().loadClass(cname);
clz.newInstance();
return;
}
} catch (Exception ex) {
System.err.println("Logging configuration class \"" + cname + "\" failed");
System.err.println("" + ex);
// keep going and useful config file.
}
}
String fname = System.getProperty("java.util.logging.config.file");
if (fname == null) {
fname = System.getProperty("java.home");
if (fname == null) {
throw new Error("Can't find java.home ??");
}
File f = new File(fname, "lib");
f = new File(f, "logging.properties");
fname = f.getCanonicalPath();
}
InputStream in = new FileInputStream(fname);
BufferedInputStream bin = new BufferedInputStream(in);
try {
readConfiguration(bin);
} finally {
if (in != null) {
in.close();
}
}
}
/**
* Reset the logging configuration.
* <p>
* For all named loggers, the reset operation removes and closes
* all Handlers and (except for the root logger) sets the level
* to null. The root logger's level is set to Level.INFO.
*
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void reset() throws SecurityException {
checkAccess();
synchronized (this) {
props = new Properties();
// Since we are doing a reset we no longer want to initialize
// the global handlers, if they haven't been initialized yet.
initializedGlobalHandlers = true;
}
Enumeration enum_ = getLoggerNames();
while (enum_.hasMoreElements()) {
String name = (String)enum_.nextElement();
resetLogger(name);
}
}
// Private method to reset an individual target logger.
private void resetLogger(String name) {
Logger logger = getLogger(name);
if (logger == null) {
return;
}
// Close all the Logger's handlers.
Handler[] targets = logger.getHandlers();
for (int i = 0; i < targets.length; i++) {
Handler h = targets[i];
logger.removeHandler(h);
try {
h.close();
} catch (Exception ex) {
// Problems closing a handler? Keep going...
}
}
if (name != null && name.equals("")) {
// This is the root logger.
logger.setLevel(defaultLevel);
} else {
logger.setLevel(null);
}
}
// get a list of whitespace separated classnames from a property.
private String[] parseClassNames(String propertyName) {
String hands = getProperty(propertyName);
if (hands == null) {
return new String[0];
}
hands = hands.trim();
int ix = 0;
Vector<String> result = new Vector<String>();
while (ix < hands.length()) {
int end = ix;
while (end < hands.length()) {
if (Character.isWhitespace(hands.charAt(end))) {
break;
}
if (hands.charAt(end) == ',') {
break;
}
end++;
}
String word = hands.substring(ix, end);
ix = end+1;
word = word.trim();
if (word.length() == 0) {
continue;
}
result.add(word);
}
return result.toArray(new String[result.size()]);
}
/**
* Reinitialize the logging properties and reread the logging configuration
* from the given stream, which should be in java.util.Properties format.
* A PropertyChangeEvent will be fired after the properties are read.
* <p>
* Any log level definitions in the new configuration file will be
* applied using Logger.setLevel(), if the target Logger exists.
*
* @param ins stream to read properties from
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
* @exception IOException if there are problems reading from the stream.
*/
public void readConfiguration(InputStream ins) throws IOException, SecurityException {
checkAccess();
reset();
// Load the properties
props.load(ins);
// Instantiate new configuration objects.
String names[] = parseClassNames("config");
for (int i = 0; i < names.length; i++) {
String word = names[i];
try {
Class clz = ClassLoader.getSystemClassLoader().loadClass(word);
clz.newInstance();
} catch (Exception ex) {
System.err.println("Can't load config class \"" + word + "\"");
System.err.println("" + ex);
// ex.printStackTrace();
}
}
// Set levels on any pre-existing loggers, based on the new properties.
setLevelsOnExistingLoggers();
// Notify any interested parties that our properties have changed.
changes.firePropertyChange(null, null, null);
// Note that we need to reinitialize global handles when
// they are first referenced.
synchronized (this) {
initializedGlobalHandlers = false;
}
}
/**
* Get the value of a logging property.
* The method returns null if the property is not found.
* @param name property name
* @return property value
*/
public String getProperty(String name) {
return props.getProperty(name);
}
// Package private method to get a String property.
// If the property is not defined we return the given
// default value.
String getStringProperty(String name, String defaultValue) {
String val = getProperty(name);
if (val == null) {
return defaultValue;
}
return val.trim();
}
// Package private method to get an integer property.
// If the property is not defined or cannot be parsed
// we return the given default value.
int getIntProperty(String name, int defaultValue) {
String val = getProperty(name);
if (val == null) {
return defaultValue;
}
try {
return Integer.parseInt(val.trim());
} catch (Exception ex) {
return defaultValue;
}
}
// Package private method to get a boolean property.
// If the property is not defined or cannot be parsed
// we return the given default value.
boolean getBooleanProperty(String name, boolean defaultValue) {
String val = getProperty(name);
if (val == null) {
return defaultValue;
}
val = val.toLowerCase();
if (val.equals("true") || val.equals("1")) {
return true;
} else if (val.equals("false") || val.equals("0")) {
return false;
}
return defaultValue;
}
// Package private method to get a Level property.
// If the property is not defined or cannot be parsed
// we return the given default value.
Level getLevelProperty(String name, Level defaultValue) {
String val = getProperty(name);
if (val == null) {
return defaultValue;
}
try {
return Level.parse(val.trim());
} catch (Exception ex) {
return defaultValue;
}
}
// Package private method to get a filter property.
// We return an instance of the class named by the "name"
// property. If the property is not defined or has problems
// we return the defaultValue.
Filter getFilterProperty(String name, Filter defaultValue) {
String val = getProperty(name);
try {
if (val != null) {
Class clz = ClassLoader.getSystemClassLoader().loadClass(val);
return (Filter) clz.newInstance();
}
} catch (Exception ex) {
// We got one of a variety of exceptions in creating the
// class or creating an instance.
// Drop through.
}
// We got an exception. Return the defaultValue.
return defaultValue;
}
// Package private method to get a formatter property.
// We return an instance of the class named by the "name"
// property. If the property is not defined or has problems
// we return the defaultValue.
Formatter getFormatterProperty(String name, Formatter defaultValue) {
String val = getProperty(name);
try {
if (val != null) {
Class clz = ClassLoader.getSystemClassLoader().loadClass(val);
return (Formatter) clz.newInstance();
}
} catch (Exception ex) {
// We got one of a variety of exceptions in creating the
// class or creating an instance.
// Drop through.
}
// We got an exception. Return the defaultValue.
return defaultValue;
}
// Private method to load the global handlers.
// We do the real work lazily, when the global handlers
// are first used.
private synchronized void initializeGlobalHandlers() {
if (initializedGlobalHandlers) {
return;
}
initializedGlobalHandlers = true;
if (deathImminent) {
// Aaargh...
// The VM is shutting down and our exit hook has been called.
// Avoid allocating global handlers.
return;
}
loadLoggerHandlers(rootLogger, null, "handlers");
}
private Permission ourPermission = new LoggingPermission("control", null);
/**
* Check that the current context is trusted to modify the logging
* configuration. This requires LoggingPermission("control").
* <p>
* If the check fails we throw a SecurityException, otherwise
* we return normally.
*
* @exception SecurityException if a security manager exists and if
* the caller does not have LoggingPermission("control").
*/
public void checkAccess() throws SecurityException {
SecurityManager sm = System.getSecurityManager();
if (sm == null) {
return;
}
sm.checkPermission(ourPermission);
}
// Nested class to represent a node in our tree of named loggers.
private static class LogNode {
HashMap<String,LogNode> children;
WeakReference<Logger> loggerRef;
LogNode parent;
LogNode(LogNode parent) {
this.parent = parent;
}
// Recursive method to walk the tree below a node and set
// a new parent logger.
void walkAndSetParent(Logger parent) {
if (children == null) {
return;
}
Iterator<LogNode> values = children.values().iterator();
while (values.hasNext()) {
LogNode node = values.next();
WeakReference<Logger> ref = node.loggerRef;
Logger logger = (ref == null) ? null : ref.get();
if (logger == null) {
node.walkAndSetParent(parent);
} else {
doSetParent(logger, parent);
}
}
}
}
// We use a subclass of Logger for the root logger, so
// that we only instantiate the global handlers when they
// are first needed.
private class RootLogger extends Logger {
private RootLogger() {
super("", null);
setLevel(defaultLevel);
}
public void log(LogRecord record) {
// Make sure that the global handlers have been instantiated.
initializeGlobalHandlers();
super.log(record);
}
public void addHandler(Handler h) {
initializeGlobalHandlers();
super.addHandler(h);
}
public void removeHandler(Handler h) {
initializeGlobalHandlers();
super.removeHandler(h);
}
public Handler[] getHandlers() {
initializeGlobalHandlers();
return super.getHandlers();
}
}
// Private method to be called when the configuration has
// changed to apply any level settings to any pre-existing loggers.
synchronized private void setLevelsOnExistingLoggers() {
Enumeration enum_ = props.propertyNames();
while (enum_.hasMoreElements()) {
String key = (String)enum_.nextElement();
if (!key.endsWith(".level")) {
// Not a level definition.
continue;
}
int ix = key.length() - 6;
String name = key.substring(0, ix);
Level level = getLevelProperty(key, null);
if (level == null) {
System.err.println("Bad level value for property: " + key);
continue;
}
Logger l = getLogger(name);
if (l == null) {
continue;
}
l.setLevel(level);
}
}
// Management Support
private static LoggingMXBean loggingMXBean = null;
/**
* String representation of the
* {@link javax.management.ObjectName} for {@link LoggingMXBean}.
* @since 1.5
*/
public final static String LOGGING_MXBEAN_NAME
= "java.util.logging:type=Logging";
/**
* Returns <tt>LoggingMXBean</tt> for managing loggers.
* An alternative way to manage loggers is using
* the {@link java.lang.management.ManagementFactory#getPlatformMXBeans(Class)
* ManagementFactory.getPlatformMXBeans} method as follows:
* <pre>
* List<{@link PlatformLoggingMXBean}> result = ManagementFactory.getPlatformMXBeans(PlatformLoggingMXBean.class);
* </pre>
*
* @return a {@link LoggingMXBean} object.
*
* @see PlatformLoggingMXBean
* @see java.lang.management.ManagementFactory
* @since 1.5
*/
public static synchronized LoggingMXBean getLoggingMXBean() {
if (loggingMXBean == null) {
loggingMXBean = new Logging();
}
return loggingMXBean;
}
}