velocity与servlet的整合

 第一天学习velocity，参考别人的blog写了一个与Servlet结合的例子，写到下面以待备份

目录结构


俩实体类代码：

Department

 

package com.velocity.bean;

public class Department {
 private int id;
 private String deptname;

 public int getId() {
  return id;
 }

 public void setId(int id) {
  this.id = id;
 }

 public String getDeptname() {
  return deptname;
 }

 public void setDeptname(String deptname) {
  this.deptname = deptname;
 }

 public Department(int id, String deptname) {
  super();
  this.id = id;
  this.deptname = deptname;
 }

 public Department() {
  super();
 }

}
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package com.velocity.bean;

public class Employee {
 private int id;
 private String ename;
 private String eaddress;
 private int age;
 private Department department;

 public int getId() {
  return id;
 }

 public void setId(int id) {
  this.id = id;
 }

 public String getEname() {
  return ename;
 }

 public void setEname(String ename) {
  this.ename = ename;
 }

 public String getEaddress() {
  return eaddress;
 }

 public void setEaddress(String eaddress) {
  this.eaddress = eaddress;
 }

 public int getAge() {
  return age;
 }

 public void setAge(int age) {
  this.age = age;
 }

 public Department getDepartment() {
  return department;
 }

 public void setDepartment(Department department) {
  this.department = department;
 }

 public Employee(int id, String ename, String eaddress, int age,
   Department department) {
  super();
  this.id = id;
  this.ename = ename;
  this.eaddress = eaddress;
  this.age = age;
  this.department = department;
 }

 public Employee() {

 }

}

 

 

看SampleServlet类

 

package com.velocity.servlet;

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

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

import org.apache.velocity.Template;
import org.apache.velocity.context.Context;

import org.apache.velocity.tools.view.servlet.VelocityViewServlet;

import com.velocity.bean.Department;
import com.velocity.bean.Employee;

@SuppressWarnings("serial")
public class SampleServlet extends VelocityViewServlet{
  //设置返回视图为text/html编码为gbk
    @Override
    protected void setContentType(HttpServletRequest request,
            HttpServletResponse response) {
        response.setContentType("text/html;charset=utf-8");
    }
   
    //处理请求
    @Override
    protected Template handleRequest(HttpServletRequest request,
            HttpServletResponse response, Context ctx){
        ctx.put("username", "张三");
        ctx.put("password", "123456789");
        ctx.put("age", "20");
        ctx.put("address", "北京");
        ctx.put("blog", "http://wcp88888888.iteye.com/");
       
        List<Employee> list=new ArrayList<Employee>();
        list.add(new Employee(1,"张三","北京",18,new Department(1,"软件研发部1")));
        list.add(new Employee(2,"张三","北京",19,new Department(2,"软件研发部2")));
        list.add(new Employee(3,"张三","北京",20,new Department(3,"软件研发部3")));
        list.add(new Employee(4,"张三","北京",21,new Department(4,"软件研发部4")));
        list.add(new Employee(5,"张三","北京",22,new Department(5,"软件研发部5")));
        list.add(new Employee(6,"张三","北京",23,new Department(6,"软件研发部6")));
        list.add(new Employee(7,"张三","北京",24,new Department(7,"软件研发部7")));
        list.add(new Employee(8,"张三","北京",25,new Department(8,"软件研发部8")));
        list.add(new Employee(9,"张三","北京",26,new Department(9,"软件研发部9")));
        list.add(new Employee(10,"张三","北京",27,new Department(10,"软件研发部10")));
       
        ctx.put("list", list);
        //调用父类的方法getTemplate()
        return getTemplate("demo.vm");
    }

}

 

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继承org.apache.velocity.tools.view.servlet.VelocityViewServlet，覆写setContentType和handleRequest方法,其中setContentType用于设置浏览器的响应,handleRequest处理用户的请求,返回Template,我们调用父类中的getTemplate()方法返回
在WEB-INF目录下创建一vm目录,用于存放模板文件
在WEB-INF目录下创建velocity.properties(名字可以任意取)
内容为

resource.loader = webapp  
webapp.resource.loader.class = org.apache.velocity.tools.view.servlet.WebappLoader
webapp.resource.loader.path=/WEB-INF/vm/  
input.encoding=utf-8  ----该处不能加双引号，要不会爆无法转换utf-8的错误
output.encoding=utf-8

resource.loader = webapp 加载方式为webapp
webapp.resource.loader.class = org.apache.velocity.tools.view.servlet.WebappLoader    webapp方式加载处理类
webapp.resource.loader.path=/WEB-INF/vm/   模板文件目录
input.encoding="gbk"  输入字符编码
output.encoding="gbk"  输出字符编码

配置web.xml

 

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
 xmlns="http://java.sun.com/xml/ns/javaee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
 
  <servlet>
        <servlet-name>customerVelocityServlet</servlet-name>
        <servlet-class>com.velocity.servlet.SampleServlet</servlet-class>
        <init-param>
            <param-name>org.apache.velocity.properties</param-name>
            <param-value>/WEB-INF/velocity.properties</param-value>
               
          
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>customerVelocityServlet</servlet-name>
        <url-pattern>/customerVelocityServlet</url-pattern>
    </servlet-mapping>
 
</web-app>

 

-----------------------------------------------------------------------------------------------------------------

<init-param>
   <param-name>org.apache.velocity.properties</param-name>
   <param-value>/WEB-INF/velocity.properties</param-value>
</init-param>
加载自定义的velocity.properties

demo.vm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
 <HEAD>
  <TITLE> velocity </TITLE>
 </HEAD>

##嘿嘿,我是velocity中的注释噢
#*
    嘿嘿,我也是velocity中的注释噢
*#

 <BODY>
    <h1>hehe,这是经过由servlet返回的velocity视图</h1>
    hello ${username},这是你的信息
    <ul>
        <li>用户密码为:${password}</li>
        <li>年龄为:${age}</li>
        <li>出生地址为:${address}</li>
        <li>个人主页为:<a href='${blog}'>${blog}</a></li>
    </ul>
    
    <br/>
    
    #foreach($emp in $!{list})
        $!{velocityCount}&nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.id} &nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.ename} &nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.eaddress} &nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.age} &nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.department.id} &nbsp;&nbsp;&nbsp;&nbsp;
        $!{emp.department.deptname} <hr/>
    #end
    
 </BODY>
</HTML>

http://localhost:8080/VelocityWeb/customerVelocityServlet
效果图