log4j

import java.io.IOException;
import java.util.Date;

import org.apache.log4j.FileAppender;
import org.apache.log4j.Logger;
import org.apache.log4j.SimpleLayout;

/*
*
* log4j的使用
    log4j需要导几个包
*
* log4j的作用：记录异常信息
* */

public class Log4jTest {
private static Logger logger = Logger.getLogger(Log4jTest.class);
private static SimpleLayout sl = new SimpleLayout();

public  static void test() throws IOException {

try {
int j = 1 / 0;
System.out.println("成功");
} catch (Exception e) {
e.printStackTrace();
System.out.println("失败");
FileAppender fa = new FileAppender(sl, "E:/log.txt", true);
logger.addAppender(fa);
logger.error(new Date().toLocaleString(), e);
logger.info(new Date().toLocaleString(), e);
logger.warn("警告了一次");
}

}

public static void main(String[] args) {
try {
test();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}