[spring] spring中bean的装配

spring中的bean的自动装配。

一、pojo包中的实体：

//Const.java
package com.wa.spring.spEL.pojo;

public class Const {
    
    private Integer id ;
    
    private String name ;

}

//User.java
package com.wa.spring.spEL.pojo;

import java.util.List;

public class User {
    
    private Integer id ;
    private String name ;
    private Double salary;
    
    private Boolean status ;
  
    private List<Son> sons;

}

//son.java
import java.util.Date;

public class Son {
    
    private Integer id ;
    
    private String name ;
    
    private Date birth;
}

//省略getter、setter方法

二.hello接口和实现类：

  

package com.wa.spring.spEL.dao;

public interface Hello {
    
    
    public String say();
    
    public String  sayTo(String str);

}


//实现类:
package com.wa.spring.spEL.dao.impl;

import com.wa.spring.spEL.dao.Hello;
import com.wa.spring.spEL.pojo.User;

public class HelloImpl implements Hello {
    
    private String name="SpEL" ;
    
    private User user ;
    
    
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    public HelloImpl(){
        
    }
    
    public HelloImpl(String name){
        this.name=name;
    }

    public String say() {
        return "spring 表达式语言:"+name;
    }

    public String sayTo(String str) {
        return "hello,"+str;
    }
    
    public void greet(){
        System.out.println("hello"+user);
    }

}

三、beans.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:c="http://www.springframework.org/schema/c"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd">
  
  <bean id="hello" class="com.wa.spring.spEL.dao.impl.HelloImpl" scope="prototype">
   <!-- 基本的构造器注入 -->
   <constructor-arg value="什么东西" />
   <!-- 基本的属性注入 -->
  <property name="user" ref="user"></property>
  </bean>
  <aop:aspectj-autoproxy proxy-target-class="true"/>
  <bean id="user" class="com.wa.spring.spEL.pojo.User">
   <!-- 引用其他bean的属性 -->
    <property name="id" value="#{const.id}"></property>
    <!-- 
    通过调用toUpperCase方法,如果为空抛出一下异常,
    org.springframework.expression.spel.SpelEvaluationException: EL1011E:(pos 11): 
    Method call: Attempted to call method toUpperCase() on null context object
    
    将 . 改为 ?.后即可避免这种情况
     -->
    <property name="name" value="#{const.name?.toUpperCase()}"></property>
    <property name="salary" value="4323.43"></property>
    <property name="status" value="true"></property>
    <property name="sons" >
    <list>
    <!-- 引用集合属性的值注入到对象中 -->
   <value type="com.wa.spring.spEL.pojo.Son"  >#{list[1]}</value>
    <ref bean="son2"/>
    </list>
    </property>
  </bean>
  <!-- 使用p命名空间装配属性
  T()运算符可以调用类的方法和常量;
  可以进行运算+,-，*,/, or,not ,!,and ,? :,==,>=,<=,
  
   -->
  <bean id="const" class="com.wa.spring.spEL.pojo.Const" p:id="#{T(java.lang.Math).random()+12}">
   <property name="name"><null/></property>
  </bean>
  
  <bean id="son1"  class="com.wa.spring.spEL.pojo.Son" 
  p:id="1" p:name="我阿凡达" >
  <property name="birth"  value="2010-02-10"></property>
  </bean>
  
  <bean id="son2" class="com.wa.spring.spEL.pojo.Son" 
  p:id="2" p:name="阿凡提">
  <property name="birth" value="2010-10-11"></property>
  </bean>
  <!--  日期类型的转换器-->
  <bean class="org.springframework.beans.factory.config.CustomEditorConfigurer">
  <property name="customEditors">
  <map>
  <entry key="java.util.Date">
  <bean class="com.wa.spring.spEL.convent.PropertyConvent">
  <property name="format" value="yyyy-MM-dd"></property>
  </bean>
  </entry>
  </map>
  </property>
  </bean>
  
  <!-- 
  util中工具类提供list,map,set等集合属性的操作和正则表达式的支持
   -->
  
  <util:list id="list">
   <bean class="com.wa.spring.spEL.pojo.Son" 
    p:id="2" p:name="son1" p:birth="2001-01-21">
   </bean>
   
   <bean class="com.wa.spring.spEL.pojo.Son" 
    p:id="3" p:name="son2" p:birth="2010-10-21">
   </bean>
   
   <bean class="com.wa.spring.spEL.pojo.Son" 
    p:id="4" p:name="son3" p:birth="2090-04-12">
   </bean>
  </util:list>

</beans>

四、日期转换类:

package com.wa.spring.spEL.convent;

import java.beans.PropertyEditorSupport;
import java.text.ParseException;
import java.text.SimpleDateFormat;

/**
 * @author Administrator
 *@Date 2015-02-01
 *日期和字符串的转换
 */
public class PropertyConvent extends PropertyEditorSupport {

    private String format="yyyy-MM-dd";
    @Override
    public void setAsText(String text) throws IllegalArgumentException {
        SimpleDateFormat sdf = new SimpleDateFormat(format);
         try {
            this.setValue(sdf.parse(text));
        } catch (ParseException e) {
            e.printStackTrace();
        }
        
    }
    public String getFormat() {
        return format;
    }
    public void setFormat(String format) {
        this.format = format;
    }
    
}

五、测试类:

package com.wa.spring.spEL.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.wa.spring.spEL.dao.impl.HelloImpl;

public class TestBean {
    
    public static void main(String[] args) {
        ApplicationContext context = new
                ClassPathXmlApplicationContext("com/wa/spring/spEL/beans.xml");
        
        HelloImpl helloImpl = (HelloImpl) context.getBean("hello");
        System.out.println(helloImpl.say());
        
        helloImpl.greet();
    }

}

 

参考信息:

Spring日期类型注入

 

 

spring配置 no matching editors or conversion strategy found 异常解决方案