jsp+servlet+JavaBean模式下,可以做個簡單的日志記錄,日志文件保存在服務器.(Tomcat)

package controller;

import java.io.File;

import java.io.IOException;

import java.util.logging.FileHandler;

import java.util.logging.Level;

import java.util.logging.Logger;

import javax.servlet.ServletConfig;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

@WebServlet(name = "test", urlPatterns = "/*")

public class MainServlet extends HttpServlet {

private static final long serialVersionUID = 7922611206674042939L;

private static final String slash = File.separator;

private static final String LOG_PATH = slash + "pro.log";

public Logger logger = null;

@Override

public void init(ServletConfig config) throws ServletException {

System.out.println("container opening");

try {

logger = Logger.getLogger(MainServlet.class.getName());

logger.setUseParentHandlers(false);

logger.addHandler(new FileHandler(config.getServletContext()

.getRealPath(LOG_PATH)));

} catch (Exception e) {

System.out.println("testing");

logger = Logger.getLogger(MainServlet.class.getName());

}

}

@Override

public void destroy() {

System.out.println("container closed");

}

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

try {

String[] str = {};

System.out.println(str[-1]);

} catch (Exception e) {

System.out.println(4);

logger.log(Level.WARNING, "數組下標越界", e);

}

}

}

日志文件一般安全要求不高,不需要至于WEB-INF目錄下,直接輸入日志名會自動生成.

java.util.logging.FileHandler類有個重寫的構造器,可選擇是否追加記錄.看具體需求.

相對于log4j有很多局限性,但適合小型項目的簡單日志記錄.

個人感覺很適合打樁使用,畢竟無需引入額外的jar包,將文件處理器修改為控制臺處理器,取消日志本地化后,就可以隨意打樁調式了.當項目部署時,調用

logger.setlevel(Level.OFF);

即可