Web开发基础_Servlet学习_0006_Servlet开发案例

案例思路

 

案例演示：

工程案例目录结构

  pom.xml：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.study</groupId>
  <artifactId>Servlet02</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>
  <dependencies>
  	<dependency>
  		<groupId>javaee</groupId>
  		<artifactId>javaee-api</artifactId>
  		<version>5</version>
  	</dependency>
  </dependencies>
</project>

web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
  <display-name>EmpManager</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  
  <servlet>
  	<servlet-name>findEmp</servlet-name>
  	<servlet-class>web.FindEmpServlet</servlet-class>
  </servlet>
  
  <servlet-mapping>
  	<servlet-name>findEmp</servlet-name>
  	<url-pattern>/findEmp</url-pattern>
  </servlet-mapping>
</web-app>

Emp：

package entity;

import java.io.Serializable;

public class Emp implements Serializable {
	
	private Integer empno;
	private String name;
	private String job;
	private Double sal;
	
	public Integer getEmpno() {
		return empno;
	}
	public void setEmpno(Integer empno) {
		this.empno = empno;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getJob() {
		return job;
	}
	public void setJob(String job) {
		this.job = job;
	}
	public Double getSal() {
		return sal;
	}
	public void setSal(Double sal) {
		this.sal = sal;
	}
}

EmpDao：

package dao;

import java.util.ArrayList;
import java.util.List;

import entity.Emp;

public class EmpDao {
	
	public List<Emp> findAll(){
		List<Emp> list = new ArrayList<Emp>();
		Emp e1 = new Emp();
		e1.setEmpno(1);
		e1.setName("唐僧");
		e1.setJob("领导");
		e1.setSal(9000.0);
		list.add(e1);
		
		Emp e2 = new Emp();
		e2.setEmpno(2);
		e2.setName("悟空");
		e2.setJob("保镖");
		e2.setSal(6000.0);
		list.add(e2);
		
		Emp e3  = new Emp();
		e3.setEmpno(3);
		e3.setName("八戒");
		e3.setJob("徒弟");
		e3.setSal(7000.0);
		list.add(e3);
		
		return list;
		
	}

}

FindEmpServlet

package web;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

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

import dao.EmpDao;
import entity.Emp;

public class FindEmpServlet extends HttpServlet{

	@Override
	protected void service(HttpServletRequest req, 
			HttpServletResponse res) throws ServletException, IOException {
		//1.接收请求数据
		//无参数 ，略
		//2.处理业务数据
		//查询全部员工
		EmpDao dao = new EmpDao();
		List<Emp> list = dao.findAll();
		//3.输出响应数据
		res.setContentType("text/html;charset=utf-8");
		PrintWriter pw	= res.getWriter();
		
		pw.println("<table border='1' width='40%' cellspacing='0'>");
		//标题行
		pw.println("	<tr>");
		pw.println("	<td>编号</td>");
		pw.println("	<td>姓名</td>");
		pw.println("	<td>职位</td>");
		pw.println("	<td>工资</td>");
		pw.println("	</tr>");
		
		//数据行
		for(Emp e :list){
			pw.println("	<tr>");
			pw.println("<td>"+e.getEmpno()+"</td>");
			pw.println("<td>"+e.getName()+"</td>");
			pw.println("<td>"+e.getJob()+"</td>");
			pw.println("<td>"+e.getSal()+"</td>");
			pw.println("	</tr>");
		}
		
		pw.println("</table>");
		pw.close();
	}
	
	

}

 将EmpManager工程部署到Tomcat上，运行Tomcat启动案例工程，

浏览器录入http://localhost:8080/EmpManager//findEmp即可：如果没有错误，最终页面展示效果应如下图：