Struts2--封装集合类型的数据（List、Map）

绝地灬酷狼 2021-08-13 12:57 349阅读 0赞

#### 封装集合类型的数据 ####

在实际的开发中，有些时候我们需要批量插入用户或者其他的对象，在Action中需要接收到多个Action中封装的对象，然后传递给业务层。那么这个时候就需要将表单的数据封装到集合中。一般我们通常使用的集合无非是List或者是Map集合。

#### 封装到List集合中 ####

User类：

public class User { 
    	
    	private String name;
    	private Integer age;
    	private Date birthday;
    	public String getName() { 
    		return name;
    	}
    	public void setName(String name) { 
    		this.name = name;
    	}
    	public Integer getAge() { 
    		return age;
    	}
    	public void setAge(Integer age) { 
    		this.age = age;
    	}
    	public Date getBirthday() { 
    		return birthday;
    	}
    	public void setBirthday(Date birthday) { 
    		this.birthday = birthday;
    	}
    	@Override
    	public String toString() { 
    		return "User [name=" + name + ", age=" + age + ", birthday=" + birthday + "]";
    	}
    	
    	
    }

表单页面listFrom.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<form action="${pageContext.request.contextPath}/ListFormAction" method="post">
    		用户名:<input type="text" name="list[0].name" /><br>
    		年龄:<input type="text" name="list[0].age" /><br>
    		用户名:<input type="text" name="list[1].name" /><br>
    		年龄:<input type="text" name="list[2].age" /><br>
    		<input type="submit" value="提交" />
    	</form>
    </body>
    </html>

ListFormAction:

public class ListFormAction extends ActionSupport{ 
    
     	private List<User> list;
     	
     	@Override
     	public String execute() throws Exception { 
     		System.out.println(list);
     		return "success";
     	}
    
    	public List<User> getList() { 
    		return list;
    	}
    
    	public void setList(List<User> list) { 
    		this.list = list;
    	}
     	
     	
    }

配置：

<action name="ListFormAction" class="pers.zhang.action.ListFormAction" method="execute" >
    	<result name="success" type="dispatcher" >/listForm.jsp</result>
    </action>

测试：  
![在这里插入图片描述][20191018230519429.png]  
控制台输出：

[User [name=tom, age=18, birthday=null], User [name=Jerry, age=null, birthday=null], User [name=null, age=28, birthday=null]]

#### 封装数据到Map集合 ####

页面mapForm.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<form action="${pageContext.request.contextPath}/MapFormAction" method="post">
    		用户名:<input type="text" name="map['one'].name" /><br>
    		年龄:<input type="text" name="map['one'].age" /><br>
    		用户名:<input type="text" name="map['two'].name" /><br>
    		年龄:<input type="text" name="map['two'].age" /><br>
    		<input type="submit" value="提交" />
    	</form>
    </body>
    </html>

MapFormAction:

public class MapFormAction extends ActionSupport{ 
    	
    	private Map<String, User> map;
    	
    	@Override
    	public String execute() throws Exception { 
    		System.out.println(map);
    		return "success";
    	}
    
    	public Map<String, User> getMap() { 
    		return map;
    	}
    
    	public void setMap(Map<String, User> map) { 
    		this.map = map;
    	}
    	
    	
    }

配置：

<action name="MapFormAction" class="pers.zhang.action.MapFormAction" method="execute" >
    	<result name="success" type="dispatcher" >/mapForm.jsp</result>
    </action>

测试：  
![在这里插入图片描述][20191018231230815.png]  
控制台打印：

{ one=User [name=tom, age=18, birthday=null], two=User [name=jerry, age=22, birthday=null]}

[20191018230519429.png]: /images/20210813/5fa029c8fb3f45dab0f76ae9563b2685.png
[20191018231230815.png]: /images/20210813/28605bbfb5ea49d9969520ffd1444ce2.png