/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.felix.ipojo.util;
import org.apache.felix.ipojo.ComponentInstance;
import org.apache.felix.ipojo.ErrorHandler;
import org.apache.felix.ipojo.Extender;
import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceReference;
import org.osgi.service.log.LogService;
/**
* iPOJO Logger.
* This class is an helper class implementing a simple log system.
* This logger sends log messages to a log service if available.
*
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
*/
public class Logger {
/**
* The iPOJO default log level property.
*/
public static final String IPOJO_LOG_LEVEL_PROP = "ipojo.log.level";
/**
* iPOJO log level manifest header.
* The uppercase 'I' is important as BND removes all headers that do not
* start with an uppercase are not added to the bundle.
* Use an upper case to support bnd.
*/
public static final String IPOJO_LOG_LEVEL_HEADER = "Ipojo-log-level";
/**
* The Log Level ERROR.
*/
public static final int ERROR = 1;
/**
* The Log Level WARNING.
*/
public static final int WARNING = 2;
/**
* The Log Level INFO.
*/
public static final int INFO = 3;
/**
* The Log Level DEBUG.
*/
public static final int DEBUG = 4;
/**
* The Bundle Context used to get the
* log service.
*/
private BundleContext m_context;
/**
* The name of the logger.
*/
private String m_name;
/**
* The instance associated to the logger if any.
*/
private ComponentInstance m_instance;
/**
* The trace level of this logger.
*/
private int m_level;
/**
* Creates a logger.
* @param context the bundle context
* @param name the name of the logger
* @param level the trace level
*/
public Logger(BundleContext context, String name, int level) {
m_name = name;
m_level = level;
m_context = context;
}
/**
* Creates a logger.
* @param context the bundle context
* @param instance the instance
* @param level the trace level
*/
public Logger(BundleContext context, ComponentInstance instance, int level) {
m_instance = instance;
m_name = m_instance.getInstanceName();
m_level = level;
m_context = context;
}
/**
* Create a logger.
* Uses the default logger level.
* @param context the bundle context
* @param name the name of the logger
*/
public Logger(BundleContext context, String name) {
this(context, name, getDefaultLevel(context));
}
/**
* Create a logger.
* Uses the default logger level.
* @param context the bundle context
* @param instance the instance
*/
public Logger(BundleContext context, ComponentInstance instance) {
this(context, instance, getDefaultLevel(context));
}
/**
* Logs a message.
* @param level the level of the message
* @param msg the the message to log
*/
public void log(int level, String msg) {
if (m_level >= level) {
dispatch(level, msg);
}
invokeErrorHandler(level, msg, null);
}
/**
* Logs a message with an exception.
* @param level the level of the message
* @param msg the message to log
* @param exception the exception attached to the message
*/
public void log(int level, String msg, Throwable exception) {
if (m_level >= level) {
dispatch(level, msg, exception);
}
invokeErrorHandler(level, msg, exception);
}
/**
* Internal log method.
* @param level the level of the message.
* @param msg the message to log
*/
private void dispatch(int level, String msg) {
LogService log = null;
ServiceReference ref = null;
try {
// Security Check
if (SecurityHelper.hasPermissionToGetService(LogService.class.getName(), m_context)) {
ref = m_context.getServiceReference(LogService.class.getName());
} else {
Extender.getIPOJOBundleContext().getServiceReference(LogService.class.getName());
}
if (ref != null) {
log = (LogService) m_context.getService(ref);
}
} catch (IllegalStateException e) {
// Handle the case where the iPOJO bundle is stopping
}
String message = null;
String name = m_name;
if (name == null) {
name = "";
}
switch (level) {
case DEBUG:
message = "[DEBUG] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_DEBUG, message);
} else {
System.err.println(message);
}
break;
case ERROR:
message = "[ERROR] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_ERROR, message);
} else {
System.err.println(message);
}
break;
case INFO:
message = "[INFO] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_INFO, message);
} else {
System.err.println(message);
}
break;
case WARNING:
message = "[WARNING] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_WARNING, message);
} else {
System.err.println(message);
}
break;
default:
message = "[UNKNOWN] " + name + " : " + msg;
System.err.println(message);
break;
}
if (log != null) {
m_context.ungetService(ref);
}
}
/**
* Internal log method.
* @param level the level of the message.
* @param msg the message to log
* @param exception the exception attached to the message
*/
private void dispatch(int level, String msg, Throwable exception) {
LogService log = null;
ServiceReference ref = null;
try {
// Security Check
if (SecurityHelper.hasPermissionToGetService(LogService.class.getName(), m_context)) {
ref = m_context.getServiceReference(LogService.class.getName());
} else {
Extender.getIPOJOBundleContext().getServiceReference(LogService.class.getName());
}
if (ref != null) {
log = (LogService) m_context.getService(ref);
}
} catch (IllegalStateException e) {
// Handle the case where the iPOJO bundle is stopping
}
String message = null;
String name = m_name;
if (name == null) {
name = "";
}
switch (level) {
case DEBUG:
message = "[DEBUG] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_DEBUG, message, exception);
} else {
System.err.println(message);
exception.printStackTrace();
}
break;
case ERROR:
message = "[ERROR] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_ERROR, message, exception);
} else {
System.err.println(message);
exception.printStackTrace();
}
break;
case INFO:
message = "[INFO] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_INFO, message, exception);
} else {
System.err.println(message);
exception.printStackTrace();
}
break;
case WARNING:
message = "[WARNING] " + name + " : " + msg;
if (log != null) {
log.log(LogService.LOG_WARNING, message, exception);
} else {
System.err.println(message);
exception.printStackTrace();
}
break;
default:
message = "[UNKNOWN] " + name + " : " + msg;
System.err.println(message);
exception.printStackTrace();
break;
}
if (log != null) {
m_context.ungetService(ref);
}
}
/**
* Invokes the error handler service is present.
* @param level the log level
* @param msg the message
* @param error the error
*/
private void invokeErrorHandler(int level, String msg, Throwable error) {
// First check the level
if (level > WARNING) {
return; // Others levels are not supported.
}
// Try to get the error handler service
try {
ServiceReference ref = m_context.getServiceReference(ErrorHandler.class.getName());
if (ref != null) {
ErrorHandler handler = (ErrorHandler) m_context.getService(ref);
if (level == ERROR) {
handler.onError(m_instance, msg, error);
} else if (level == WARNING) {
handler.onWarning(m_instance, msg, error);
} // The others case are not supported
m_context.ungetService(ref);
return;
} // Else do nothing...
} catch (IllegalStateException e) {
// Ignore
// The iPOJO bundle is stopping.
}
}
/**
* Gets the default logger level.
* The property is searched inside the framework properties,
* the system properties, and in the manifest from the given
* bundle context. By default, set the level to {@link Logger#WARNING}.
* @param context the bundle context.
* @return the default log level.
*/
private static int getDefaultLevel(BundleContext context) {
// First check in the framework and in the system properties
String level = context.getProperty(IPOJO_LOG_LEVEL_PROP);
// If null, look in the bundle manifest
if (level == null) {
String key = IPOJO_LOG_LEVEL_PROP.replace('.', '-');
level = (String) context.getBundle().getHeaders().get(key);
}
// if still null try the second header
if (level == null) {
level = (String) context.getBundle().getHeaders().get(IPOJO_LOG_LEVEL_HEADER);
}
if (level != null) {
if (level.equalsIgnoreCase("info")) {
return INFO;
} else if (level.equalsIgnoreCase("debug")) {
return DEBUG;
} else if (level.equalsIgnoreCase("warning")) {
return WARNING;
} else if (level.equalsIgnoreCase("error")) {
return ERROR;
}
}
// Either l is null, either the specified log level was unknown
// Set the default to WARNING
return WARNING;
}
}