一、自动装配：
Model类：
People.java:
package com.cy.entity;
public class People {
private int id;
private String name;
private int age;
private Dog dog;
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public Dog getDog() {
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
@Override
public String toString() {
return "People [id=" + id + ", name=" + name + ", age=" + age
+ ", dog=" + dog.getName() + "]";
}
}
Dog.java:
package com.cy.entity;
public class Dog {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
beans.xml spring加载bean配置文件：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd"
default-autowire="byName"> <bean id="dog" class="com.cy.entity.Dog">
<property name="name" value="Jack"></property>
</bean> <bean id="dog2" class="com.cy.entity.Dog">
<property name="name" value="Tom"></property>
</bean> <bean id="people1" class="com.cy.entity.People">
<property name="id" value="1"></property>
<property name="name" value="张三"></property>
<property name="age" value="11"></property>
</bean> </beans>
测试代码：
T.java:
package com.cy.test; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.cy.entity.People; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} @Test
public void test() {
People people = (People) ac.getBean("people1");
System.out.println(people); //People [id=1, name=张三, age=11, dog=Jack]
} }
二、方法注入：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd"> <！-- prototype配置dog为多例模式 -->
<bean id="dog" class="com.java1234.entity.Dog" scope="prototype">
<property name="name" value="Jack"></property>
</bean> <bean id="people1" class="com.java1234.entity.People">
<property name="id" value="1"></property>
<property name="name" value="张三"></property>
<property name="age" value="11"></property>
<lookup-method name="getDog" bean="dog"/>
</bean> </beans>
People中的getDog为抽象方法，这样在getDog时，由spring来注入具体的dog：
People.java:
package com.java1234.entity;
public abstract class People {
private int id;
private String name;
private int age;
private Dog dog;
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public abstract Dog getDog();
public void setDog(Dog dog) {
this.dog = dog;
}
@Override
public String toString() {
return "People [id=" + id + ", name=" + name + ", age=" + age
+ ", dog=" + dog.getName() + "]";
}
}
测试代码：
package com.java1234.test; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.java1234.entity.People; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} @Test
public void test1() {
People people=(People)ac.getBean("people1");
People people2=(People)ac.getBean("people1");
System.out.println(people.getDog()==people2.getDog()); //false people每次装配的dog都不一样 System.out.println(ac.getBean("dog")==ac.getBean("dog")); //false dog为多例，每次获取都不一样
} }
三、方法替换，不常用，了解下就行了：
People.java:
package com.java1234.entity;
public class People {
private int id;
private String name;
private int age;
private Dog dog;
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public Dog getDog() {
Dog dog=new Dog();
dog.setName("Jack");
return dog;
}
public void setDog(Dog dog) {
this.dog = dog;
}
@Override
public String toString() {
return "People [id=" + id + ", name=" + name + ", age=" + age
+ ", dog=" + dog.getName() + "]";
}
}
People2.java:
package com.java1234.entity;
import java.lang.reflect.Method;
import org.springframework.beans.factory.support.MethodReplacer;
public class People2 implements MethodReplacer {
@Override
public Object reimplement(Object arg0, Method arg1, Object[] arg2)
throws Throwable {
Dog dog=new Dog();
dog.setName("Tom");
return dog;
}
}
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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd"> <bean id="people1" class="com.java1234.entity.People">
<property name="id" value="1"></property>
<property name="name" value="张三"></property>
<property name="age" value="11"></property>
<replaced-method name="getDog" replacer="people2"></replaced-method><!-- people1中的getDog方法被替换，被people2中的方法替换掉了 -->
</bean> <bean id="people2" class="com.java1234.entity.People2"></bean>
</beans>
测试代码：
package com.java1234.test; import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext; import com.java1234.entity.People; public class T { private ApplicationContext ac; @Before
public void setUp() throws Exception {
ac=new ClassPathXmlApplicationContext("beans.xml");
} @Test
public void test1() {
People people=(People)ac.getBean("people1");
System.out.println(people.getDog().getName());
} }