Tomcat和Servlet入门 - 码农教程

Tomcat安装

首先找到tomcat的tomcat插件中找到把两个jar包导入ecilpse中的plugins中

Web项目的结构和其中的内容然后在windows中的reference中输入tomcat中设置该tomcat中的该tomcat中的版本和路径

Javaweb项目搭建

Web项目结构

项目名

　　WEB-INF

　　　　lib

　　　　classes

　　　　web.xml

　　Index.html

部署

两种方式

1. 把整个项目放入tomcat中的webapps然后

<Context docBase="" path=""/>中部署

web.xml中的设置

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
  version="3.1"
  <!-- false和true的方式true为通过下面注解反射而false是通过注解反射 -->
  metadata-complete="false">
  <!-- 请求路径 -->
  <servlet>
      <servlet-name>qq</servlet-name>
      <servlet-class>cn.jiedada.serlevt.HelloSerlvet</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>qq</servlet-name>
      <url-pattern>/hello</url-pattern>
  </servlet-mapping>
   <servlet>
      <servlet-name>ff</servlet-name>
      <servlet-class>cn.jiedada.serlevt.LifeServer</servlet-class>
      <init-param>
          <param-name>coding</param-name>
          <param-value>utf-8</param-value>
      </init-param>
  </servlet>
  <servlet-mapping>
      <servlet-name>ff</servlet-name>
      <url-pattern>/xml</url-pattern>
  </servlet-mapping>
</web-app>

2.通过tomcat然后复制项目名的位置就可以了

搭建项目

Servlet入门

index.html中的文件

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>    
    <form action="forGet" method="get">
            <h2>get请求</h2>
            账号：<input type="text" name="name"><br></br>
            密码：<input type="password" name="pwd"><br></br>
            <input type="submit" value="提交">
    </form>
    <hr/>
    <form action="forPost" method="post">
            <h2>post请求</h2>
            账号：<input type="text" name="name"><br></br>
            密码：<input type="password" name="pwd"><br></br>
            <input type="submit" value="提交">
    </form>
</body>
</html>

1. 连接

package cn.jiedada.serlevt;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class HelloSerlvet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("欢迎您");
    }
}

View Code

打印到控制台

2. 生命周期

package cn.jiedada.serlevt;

import java.io.IOException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class LifeServer extends HttpServlet {
    ServletConfig config;
    public LifeServer() {
        System.out.println("这是构造方法");
    }
    @Override
    public void init() throws ServletException {
        System.out.println("这是一个init");
    }
    @Override
    public void init(ServletConfig config) throws ServletException {
        this.config=config;
        System.out.println("这是一个config方法");
    }
    @Override
    protected void service(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException {
        System.out.println("这是主题");
        System.out.println(config.getServletName());
        System.out.println(config.getInitParameter("coding"));
    }
    @Override
    public void destroy() {
        System.out.println("销毁方法");
    }
}

View Code

3. 获得网页的get和post请求中的数据

4. 通过Java后台页面发送数据

package cn.jiedada.serlevt;

import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
//注解也可以多个反射，通过该方法找到几种反射
@WebServlet(urlPatterns={"/forGet","/forPost"})
public class MyServiceTest extends HttpServlet {
    @Override
    protected void service(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException {
        //通过post请求返回的文字为utf-8
        arg0.setCharacterEncoding("utf-8");
        System.out.println(arg0.getParameter("name"));
        System.out.println(arg0.getParameter("pwd"));
        //把Java文件中的数据输出到页面
        ServletOutputStream os = arg1.getOutputStream();
        //页面返回值设置
        arg1.setContentType("text/html;charset=utf-8");
        //字节流转换为字符流
        OutputStreamWriter osw = new OutputStreamWriter(os);
        PrintWriter pw = new PrintWriter(osw,true);
        pw.println("这是一个表");
    }
}

View Code

5. 访问过程，先通过继承httpservlet继承，然后先寻找xml是否有该界面，然后在WEB-INF下面寻找界面

6. 注意

false和true的方式true为通过下面注解反射而false是通过注解反射 metadata-complete="false">

原文地址：https://www.cnblogs.com/xiaoruirui/p/11375298.html