关于log4j和commons-logging的一些疑惑？求指点

[飞火流云]

1. 请问log4j和commons-logging的区别在哪里?
2. 希望将将同一个包内的不同的类的日志输出到同一个指定文件中。
为实现该目的，代码实现如下:

package logTest;

import org.apache.commons.logging.Log;   
import org.apache.commons.logging.LogFactory; 

public class LogTest {

	 public static final Log LOG =
			    LogFactory.getLog(LogTest.class);
	 
	 public void test() {
		 LOG.info("test1") ;
		 LOG.debug("test1") ;
	 }
}


package logTest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class LogTest2 {
	 public static final Log LOG =
			    LogFactory.getLog(LogTest2.class);
	 
	public static void main(String[] args) {
		LOG.info("test2") ;
		LOG.debug("test2") ;
		new LogTest().test() ;
	}

}


log4j.properties配置如下
#   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.

LOG_DIR=F://LogTest/
log4j.rootLogger=INFO,console

#Console
log4j.appender.console=org.apache.log4j.ConsoleAppender  
log4j.appender.console.Target=System.out  
log4j.appender.console.layout=org.apache.log4j.PatternLayout  
log4j.appender.console.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss} [%c-%L]-[%p] %m%n  

#test package print out
log4j.logger.logTest=INFO,logT  
log4j.appender.logT=org.apache.log4j.RollingFileAppender  
log4j.appender.logT.MaxFileSize=10240KB  
log4j.appender.logT.MaxBackupIndex=2  
log4j.appender.logT.File=${LOG_DIR}/test.log  
log4j.appender.logT.layout=org.apache.log4j.PatternLayout  
log4j.appender.logT.layout.ConversionPattern=%-d{yyyy-MM-dd HH\:mm\:ss} [%c-%L]-[%p] %m%n

结果输出:
log4j:WARN No appenders could be found for logger (logTest.LogTest2).
log4j:WARN Please initialize the log4j system properly.

不知道哪里错了?

[飞火流云]

明明是输出同一个包内的文件，为啥总提示我单个类的文件配置不对呢? 奇怪了 log4j:WARN No appenders could be found for logger (logTest.LogTest2).

[飞火流云]

不知道问题在哪里？ 配置似乎没有问题，我的目的是配置整个包的日志输出而非单个类，为什么会有: log4j:WARN No appenders could be found for logger (logTest.LogTest2).?