spring4笔记----使用装配注入合作者Bean的三种方式

1. no ：不自动装配
2. byName ：id（name）与setter方法去set前缀，并小写首字母后同名的Bean完成注入，如有多个匹配则抛异常
3. byType ：spring容器找全部bean，如果找到单单一个bean类型和setter方法形参类型匹配的则完成注入，如有多个匹配则抛异常

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两个名字相同抛异常情况例子：

Exception in thread "main" org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Bean name 'd' is already used in this <beans> element
Offending resource: class path resource [beans.xml]

    at org.springframework.beans.factory.parsing.FailFastProblemReporter.error(FailFastProblemReporter.java:70)
    at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:85)
    at org.springframework.beans.factory.parsing.ReaderContext.error(ReaderContext.java:80)
    at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.error(BeanDefinitionParserDelegate.java:301)
    at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.checkNameUniqueness(BeanDefinitionParserDelegate.java:511)
    at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseBeanDefinitionElement(BeanDefinitionParserDelegate.java:457)
    at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseBeanDefinitionElement(BeanDefinitionParserDelegate.java:429)
    at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.processBeanDefinition(DefaultBeanDefinitionDocumentReader.java:299)
    at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseDefaultElement(DefaultBeanDefinitionDocumentReader.java:190)
    at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:169)
    at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:142)
    at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:94)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:508)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:392)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:336)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:181)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:217)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:252)
    at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:127)
    at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:93)
    at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:129)
    at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:612)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:513)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
    at com.ij34.bean.test.main(test.java:12)

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接口

package com.ij34.interfaces;

public interface dog {
 public String run();
}

package com.ij34.interfaces;

public interface people {
   public void test();
}

---

对象

package com.ij34.servce;

import com.ij34.interfaces.dog;

public class Dog implements dog{
   private String name;

public String getName() {
    return name;
}

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

@Override
public String run() {
    // TODO Auto-generated method stub
    return "我是一只阿拉斯加狗，名字叫："+getName();
}
   
}

package com.ij34.servce;

import com.ij34.interfaces.dog;

public class Dog2 implements dog{
   private String name;

public String getName() {
    return name;
}

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

@Override
public String run() {
    // TODO Auto-generated method stub
    return "我是一只哈奇士狗，名字叫："+getName();
}
   
}

package com.ij34.servce;

import com.ij34.interfaces.dog;
import com.ij34.interfaces.people;

public class People implements people{
  private dog d;
  

    public dog getD() {
    return d;
}


public void setD(dog d) {
    this.d = d;
}


    @Override
    public void test() {
        // TODO Auto-generated method stub
        System.out.println("我是程序员："+getD().run());
    }

}

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<?xml version="1.0" encoding="GBK"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://www.springframework.org/schema/beans"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-4.3.xsd">
<bean id="chinese" class="com.ij34.servce.People" autowire="byName" />  <!-- 或者byType -->
<bean name="d" class="com.ij34.servce.Dog" >
<property name="name" value="牛仔1"></property>  
</bean>

<bean name="d1" class="com.ij34.servce.Dog2" >  <!-- 多个，另外的里面添加: autowire-candidate="false"-->
<property name="name" value="大哈2狗"></property>
</bean>
</beans>

---

运行

package com.ij34.bean;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.ij34.servce.People;

public class test {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
          @SuppressWarnings("resource")
        ApplicationContext app=new ClassPathXmlApplicationContext("beans.xml");
        People p=app.getBean("chinese", People.class);
        p.test();
    }

}

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