filter过滤器的使用

最新推荐文章于 2025-12-08 16:37:50 发布

原创最新推荐文章于 2025-12-08 16:37:50 发布 · 77 阅读

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#servlet #java #开发语言

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该文章展示了如何使用Java创建一个Servlet（servletDemo01）以及一个过滤器（FilterDemo01）。Servlet处理HTTP请求，打印出servletDemo01执行了。过滤器filterDemo01在请求处理前执行，设置响应内容类型并调用FilterChain放行请求。

package com.itheima.serlvet;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

@WebServlet("/servletDemo01")
public class servletDemo01 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("servletDemo01 执行了");
        //resp.setContentType("text/html;charset=UTF-8");
        resp.getWriter().write("servletDemo01 执行了");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req,resp);
    }
}

package com.itheima.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import java.io.IOException;

/*过滤器的基本使用*/
@WebFilter("/*")
public class FilterDemo01 implements Filter {


    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("filterDemo01执行了。。。。。");
        servletResponse.setContentType("text/html;charset=UTF-8");
        //放行
        filterChain.doFilter(servletRequest,servletResponse);
    }


}