CRUD是Create（创建）、Read（读取）、Update（更新）和Delete（删除）
首先，肯定是要与数据交互的，所以我们先写一个bean类
代码如下：
public class Food {
private Integer id;
private String name;
private Double price;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Double getPrice() {
return price;
}
public void setPrice(Double price) {
this.price = price;
}
public Food(Integer id, String name, Double price) {
super();
this.id = id;
this.name = name;
this.price = price;
}
public Food() {
super();
// TODO Auto-generated constructor stub
}
@Override
public String toString() {
return "Food [id=" + id + ", name=" + name + ", price=" + price + "]";
}
}在bean类中创建的字段，与数据库中的字段相对应，
下面是Dao代码：
Dao接口：
public interface FoodDaoI {
//列表展示
List<Food> showFoodList();
//删除操作
void delFoodById(Integer id);
//添加操作
void addFood(Food food);
//更新前回显
Food findById(Integer id);
//更新
void updateFood(Food food);
}Dao实现类：
public class FoodDaoImpl implements FoodDaoI{
private QueryRunner qr=new QueryRunner(JDBCUtils3.getDataSource());
public List<Food> showFoodList() {
String sql="select * from ee";
List<Food> list=null;
try {
list=qr.query(sql, new BeanListHandler<Food>(Food.class));
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return list;
}
public void delFoodById(Integer id) {
String sql="delete from ee where id=?";
try {
qr.update(sql, id);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void addFood(Food food) {
String sql="insert into ee set id=?,name=?,price=?";
try {
qr.update(sql, food.getId(),food.getName(),food.getPrice());
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public Food findById(Integer id) {
String sql="select * from ee where id=?";
Food food=null;
try {
food=qr.query(sql, new BeanHandler<Food>(Food.class),id);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return food;
}
public void updateFood(Food food) {
String sql="update ee set name=?, price=? where id=?";
try {
qr.update(sql, food.getName(),food.getPrice(),food.getId());
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
然后是action类，代码如下：
public class FoodAction extends ActionSupport implements ModelDriven<Food>{
private FoodDaoI foodDao=new FoodDaoImpl();
private static final long serialVersionUID = 5418396635382987020L;
private List<Food> list;
private Food food=new Food();
//列表展示
public String list() {
list = foodDao.showFoodList();
return "list";
}
//删除操作
public String delete() {
foodDao.delFoodById(food.getId());
return "delete";
}
//添加操作
public String add() {
foodDao.addFood(food);
return "add";
}
//更新前回显
public String toupdate() {
food=foodDao.findById(food.getId());
ServletActionContext.getRequest().setAttribute("food", food);
return "toupdate";
}
//更新操作
public String update() {
foodDao.updateFood(food);
return "update";
}
//*****************************************
public FoodDaoI getFoodDao() {
return foodDao;
}
public void setFoodDao(FoodDaoI foodDao) {
this.foodDao = foodDao;
}
public List<Food> getList() {
return list;
}
public void setList(List<Food> list) {
this.list = list;
}
public Food getFood() {
return food;
}
public void setFood(Food food) {
this.food = food;
}
public Food getModel() {
// TODO Auto-generated method stub
return food;
}
}需要注意的是，本例子在action中实现了ModelDriven<>类，所以需要设置action类中，相应的getter/setter方法
接下来是struts.xml文件的配置：
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<package name="Struts2_CRUD_DEMO" extends="struts-default" namespace="/">
<action name="action_*" class="com.baidu.action.FoodAction" method="{1}" >
<result name="list" >/list.jsp</result>
<result name="delete" type="redirect">action_list</result>
<result name="add" type="redirect">action_list</result>
<result name="toupdate">/update.jsp</result>
<result name="update" type="redirect">action_list</result>
</action>
</package>
</struts>在strutsxml文件中需要注意的是方法之间重定向的时候需要设置<result>标签中的type属性
下面是jsp：
列表展示jsp：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
function del(id) {
location.href="action_delete?id="+id;
}
function toUpdate(id) {
location.href="action_toupdate?id="+id;
}
</script>
</head>
<body>
<h2>Food List</h2>
<table border="1" style="align-content: center;">
<tr>
<td>id</td>
<td>name</td>
<td>price</td>
</tr>
<c:forEach items="${list }" var="food">
<tr>
<td>${food.id }</td>
<td>${food.name }</td>
<td>${food.price }</td>
<td>
<button onclick="del(${food.id })">删除</button>
</td>
<td>
<button onclick="toUpdate(${food.id })">修改</button>
</td>
</tr>
</c:forEach>
</table>
<a href="add.jsp">添加</a>
</body>
</html>更新界面jsp：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="action_update" method="post">
<input type="hidden" name="id" value="${food.id }">
姓名：<input type="text" value="${food.name }" name="name"><br>
价格：<input type="text" value="${food.price }" name="price"><br>
<input type="submit" value="提交">
</form>
</body>
</html>添加界面jsp：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
</script>
</head>
<body>
<form action="action_add" method="post">
<input type="hidden" name="food.id">
姓名：<input type="text" value="" name="name"><br>
价格：<input type="text" value="" name="price"><br>
<input type="submit" value="提交">
</form>
</body>
</html>写这个简单例子，主要是为了帮助刚刚接触Struts2这个框架的初学者，能更好的去理解Struts2框架，并学会如何使用，如果有同学想要本例子中相关jar包，可以给博主要哦