/*
* 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.click.service;
import javax.servlet.ServletContext;
import org.apache.click.util.HtmlStringBuffer;
/**
* Provides a Log Service class which will log messages to the console or
* <tt>System.out</tt>.
* <p/>
* ConsoleLogService is the default {@link LogService} for Click.
* <p/>
* However you can instruct Click to use a different log service implementation.
* Please see {@link LogService} for more details.
*/
public class ConsoleLogService implements LogService {
// -------------------------------------------------------------- Constants
/** The trace logging level. */
public static final int TRACE_LEVEL = -1;
/** The debug logging level. */
public static final int DEBUG_LEVEL = 0;
/** The info logging level. */
public static final int INFO_LEVEL = 1;
/** The warn logging level. */
public static final int WARN_LEVEL = 2;
/** The error logging level. */
public static final int ERROR_LEVEL = 3;
/** The level names. */
protected static final String[] LEVELS =
{ " [trace] ", " [debug] ", " [info ] ", " [warn ] ", " [error] " };
// ----------------------------------------------------- Instance Variables
/** The logging level. */
protected int logLevel = INFO_LEVEL;
/** The log name. */
protected String name = "Click";
// --------------------------------------------------------- Public Methods
/**
* @see LogService#onInit(ServletContext)
*
* @param servletContext the application servlet context
* @throws Exception if an error occurs initializing the LogService
*/
public void onInit(ServletContext servletContext) throws Exception {
}
/**
* @see LogService#onDestroy()
*/
public void onDestroy() {
}
/**
* Set the logging level
* <tt>[ TRACE_LEVEL | DEBUG_LEVEL | INFO_LEVEL | WARN_LEVEL | ERROR_LEVEL ]</tt>.
*
* @param level the logging level
*/
public void setLevel(int level) {
logLevel = level;
}
/**
* @see LogService#debug(Object)
*
* @param message the message to log
*/
public void debug(Object message) {
log(DEBUG_LEVEL, String.valueOf(message), null);
}
/**
* @see LogService#debug(Object, Throwable)
*
* @param message the message to log
* @param error the error to log
*/
public void debug(Object message, Throwable error) {
log(DEBUG_LEVEL, String.valueOf(message), error);
}
/**
* @see LogService#error(Object)
*
* @param message the message to log
*/
public void error(Object message) {
log(ERROR_LEVEL, String.valueOf(message), null);
}
/**
* @see LogService#error(Object, Throwable)
*
* @param message the message to log
* @param error the error to log
*/
public void error(Object message, Throwable error) {
log(ERROR_LEVEL, String.valueOf(message), error);
}
/**
* @see LogService#info(Object)
*
* @param message the message to log
*/
public void info(Object message) {
log(INFO_LEVEL, String.valueOf(message), null);
}
/**
* @see LogService#info(Object, Throwable)
*
* @param message the message to log
* @param error the error to log
*/
public void info(Object message, Throwable error) {
log(INFO_LEVEL, String.valueOf(message), error);
}
/**
* @see LogService#trace(Object)
*
* @param message the message to log
*/
public void trace(Object message) {
log(TRACE_LEVEL, String.valueOf(message), null);
}
/**
* @see LogService#trace(Object, Throwable)
*
* @param message the message to log
* @param error the error to log
*/
public void trace(Object message, Throwable error) {
log(TRACE_LEVEL, String.valueOf(message), error);
}
/**
* @see LogService#warn(Object)
*
* @param message the message to log
*/
public void warn(Object message) {
log(WARN_LEVEL, String.valueOf(message), null);
}
/**
* @see LogService#warn(Object, Throwable)
*
* @param message the message to log
* @param error the error to log
*/
public void warn(Object message, Throwable error) {
log(WARN_LEVEL, String.valueOf(message), error);
}
/**
* @see LogService#isDebugEnabled()
*
* @return true if [debug] level logging is enabled
*/
public boolean isDebugEnabled() {
return logLevel <= DEBUG_LEVEL;
}
/**
* @see LogService#isInfoEnabled()
*
* @return true if [info] level logging is enabled
*/
public boolean isInfoEnabled() {
return logLevel <= INFO_LEVEL;
}
/**
* @see LogService#isTraceEnabled()
*
* @return true if [trace] level logging is enabled
*/
public boolean isTraceEnabled() {
return logLevel <= TRACE_LEVEL;
}
// ------------------------------------------------------ Protected Methods
/**
* Log the given message and optional error at the specified logging level.
*
* @param level the logging level
* @param message the message to log
* @param error the optional error to log
*/
protected void log(int level, String message, Throwable error) {
if (level < logLevel) {
return;
}
HtmlStringBuffer buffer = new HtmlStringBuffer();
buffer.append("[");
buffer.append(name);
buffer.append("]");
buffer.append(LEVELS[level + 1]);
buffer.append(message);
if (error != null) {
System.out.print(buffer.toString());
error.printStackTrace(System.out);
} else {
System.out.println(buffer.toString());
}
}
}