Javaweb - 使用Servlet模板创建类，Request请求参数中文乱码处理

使用Servlet模板创建Servlet更高效

新建测试类setting设置测试--直接新建servlet模板

创建模板servlet类成功 Request请求参数中文乱码处理

测试录入中文参数解决post请求乱码

测试 解决Get请求乱码

解决思路相关代码运行测试注意 小结

RequestDemo4.java

package com.taotao.web;

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

public class RequestDemo4 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        
    }

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

    }
}

稍微修改下模板

记得往下翻翻才能找到这个Servlet模板创建选项

请求参数中出现中文，则会乱码

我们在RequestDemo4类中测试

package com.taotao.web;

import javax.jws.WebService;
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("/req4")
public class RequestDemo4 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1.获取username
        String username = req.getParameter("username");
        System.out.println(username);
    }

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

    }
}

POST:设置输入流的编码

req.setCharacterEncoding("UTF-8");

Tomcat默认解码使用的“Iso - 8859 - 1“字符集。

所以，我们只需要再次对tomcat的字符集进行编码，转为字节数组，然后由字节数组再解码，转为utf - 8

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


        //获取username
        String username = req.getParameter("username");

        //对ISO_8859-1进行编码，转为字节数组，ISO_8859-1这是tomcat进行的url解码
        byte[] bytes = username.getBytes(StandardCharsets.ISO_8859_1);
        //对字符数据进行解码
        String userName = new String(bytes, StandardCharsets.UTF_8);
        System.out.println(userName);
    }

此方法Post请求也可以使用，但是不如另一个方便

Tomacat8.0后，已将get请求默认的解码方式改为UTF-8，所以一般不需要转换