【java 4】---根据名称或类型完成自动装配

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【java 4】---根据名称或类型完成自动装配

前言：

根据名称或类型配置有什么好处呢？

这样可以减少很多的配置量，特别是代码量？

根据名称那到底怎么配置呢？

 http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">

中添加：default-autowire="byName" 根据名字自动匹配：

http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd" default-autowire="byName">

实践完整代码：

Bean2.java:

package com.bjpowernode.spring;public class Bean2 {    private Bean3 bean3;    private Bean4 bean4;    private Bean5 bean5;    public Bean3 getBean3() {        return bean3;    }    public void setBean3(Bean3 bean3) {        this.bean3 = bean3;    }    public Bean4 getBean4() {        return bean4;    }    public void setBean4(Bean4 bean4) {        this.bean4 = bean4;    }    public Bean5 getBean5() {        return bean5;    }    public void setBean5(Bean5 bean5) {        this.bean5 = bean5;    }    }

Bean3.java:

package com.bjpowernode.spring;public class Bean3 {    private int id;    private String name;    private String sex;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getSex() {        return sex;    }    public void setSex(String sex) {        this.sex = sex;    }    }

Bean4.java:

package com.bjpowernode.spring;public class Bean4 {    private int id;    private String name;    private String sex;    private  int age;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getSex() {        return sex;    }    public void setSex(String sex) {        this.sex = sex;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    }

Bean5.java:

package com.bjpowernode.spring;public class Bean5 {    private String password;    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }        }

AutoWireTest.java:

package test;import org.springframework.beans.factory.BeanFactory;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.bjpowernode.spring.Bean2;import junit.framework.TestCase;public class AutoWireTest extends TestCase {    private BeanFactory factory;       @Override    protected void setUp() throws Exception {        //读取的方式一：      //String[] configLocation=new String[]{ "applicationContext-beans.xml","applicationContext-editor.xml"};      //factory=new ClassPathXmlApplicationContext(configLocation);             // factory=new ClassPathXmlApplicationContext("applicationContext.xml");              //读取方式二：       factory = new ClassPathXmlApplicationContext("applicationContext-beans.xml");           }                 /*protected void tearDown() throws Exception {        // TODO Auto-generated method stub            }*/       /*public void testInjection1()    {       //简单的new 一下，属性是不会注入的，必须从容器中拿出来       //Bean bean=new Bean();普通的new 不会被注入                         Bean1 bean1=(Bean1)factory.getBean("bean1");        System.out.println("bean.strValue= " + bean1.getStrValue());        System.out.println("bean.intValue= " + bean1.getIntValue());        System.out.println("bean.listValue= " + bean1.getListValue());        System.out.println("bean.setValue= " + bean1.getSetValue());        System.out.println("bean.arrayValue= " + bean1.getArrayValue());        System.out.println("bean.mapValue= " + bean1.getMapValue());        System.out.println("bean.dateValue= " + bean1.getDateValue());            }    */          public void testInjection1()    {       //简单的new 一下，属性是不会注入的，必须从容器中拿出来       //Bean bean=new Bean();普通的new 不会被注入                         Bean2 bean2=(Bean2)factory.getBean("bean2");        System.out.println("bean2.bean3.id= " + bean2.getBean3().getId());        System.out.println("bean2.bean3.name= " + bean2.getBean3().getName());        System.out.println("bean2.bean3.sex= " + bean2.getBean3().getSex());        System.out.println("bean2.bean4.id= " + bean2.getBean4().getId());        System.out.println("bean2.bean4.name= " + bean2.getBean4().getName());        System.out.println("bean2.bean4.sex= " + bean2.getBean4().getSex());        System.out.println("bean2.bean4.age= " + bean2.getBean4().getAge());        System.out.println("bean2.bean5.password= " + bean2.getBean5().getPassword());            }    }

applicationContext.xml

关键就是在配置文件中的配置：

<?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:tx="http://www.springframework.org/schema/tx"         xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd           http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd" default-autowire="byName"><!-- 自动配置，自动找，根据名字相同 default-autowire="byName" --><!-- <bean id="bean2" class="com.bjpowernode.spring.Bean2">      <property name="bean3" ref="bean3"/>      <property name="bean4" ref="bean4"/>       <property name="bean5" ref="bean5"/> </bean>--><bean id="bean2" class="com.bjpowernode.spring.Bean2"/><bean id="bean3" class="com.bjpowernode.spring.Bean3">    <property name="id" value="100"/>    <property name="name" value="Daniel"/>    <property name="sex" value="male"/></bean> <bean id="bean4" class="com.bjpowernode.spring.Bean4">    <property name="id" value="100"/>    <property name="name" value="Daniel"/>    <property name="sex" value="male"/>    <property name="age" value="102"/></bean><bean id="bean5" class="com.bjpowernode.spring.Bean5">    <property name="password" value="1"/></bean></beans>

单元测试运行结果：成功如下

根据类型自动匹配：

上面我们介绍了更加名字自动匹配，那么怎么根据类型自动匹配呢？

原理是一样，就是添加一句话罢了，详细如下：

 http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">

在这句中添加：

 default-autowire="byType"

得到如下：

http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd" default-autowire="byType">

小结：

开发阶段，为了提高速度和效率，在配置文件中是可以更加名字或类型自动匹配。好

处是开发快，但是后面是强烈建议不上具体的注释，为了方便了解，对于的配置和注

释，能更好的调错和维护。

对比：相对于根据名字自动配置来说，还是相对类型配置是更方便，更安全的。

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【java 4】---根据名称或类型 完成自动装配

前言：