一、构造方法注入(死的应用)
 
通过constructor-arg指定构造方法的参数
Source.java
  1. package com.gary.test;
  3. public class Source {
  5. public void helloWorld(){
  6. System.out.println("Hello World!");
  7. }
  8. }
 Target.java
  1. package com.gary.test;
  3. public class Target {
  5. private Source source;
  7. public Target(Source source){
  8. this.source = source;
  9. }
  11. public void sayHelloWorld(){
  12. source.helloWorld();
  13. }
  15. }
applicationContext.xml
 
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <beans
  3. xmlns="http://www.springframework.org/schema/beans"
  4. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  5. xmlns:p="http://www.springframework.org/schema/p"
  6. xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
  8. <bean id="source" class="com.gary.test.Source" />
  9. <bean id="target" class="com.gary.test.Target">
  10. <constructor-arg ref="source" />
  11. </bean>
  12. </beans>
TargetTest.java
 
  1. package com.gary.test;
  3. import org.junit.AfterClass;
  4. import org.junit.BeforeClass;
  5. import org.junit.Test;
  6. import org.springframework.beans.factory.BeanFactory;
  7. import org.springframework.context.support.ClassPathXmlApplicationContext;
  9. public class TargetTest {
  11. static BeanFactory factory = null;
  12. static Target target = null;
  14. @BeforeClass
  15. public static void setUpBeforeClass() throws Exception {
  16. try{
  17. factory = new ClassPathXmlApplicationContext("applicationContext.xml");
  18. target = (Target) factory.getBean("target");
  19. }catch(Exception e){
  20. e.printStackTrace();
  21. }
  22. }
  24. @AfterClass
  25. public static void tearDownAfterClass() throws Exception {
  27. }
  29. @Test
  30. public void testSayHelloWorld() {
  31. target.sayHelloWorld();
  32. }
  34. }
二、getter()和setter()方法注入(比较常用)
 
 
通过访问器方法(set)注入
此方法较为常用.在目标类中,定义要注入的属性,并添加访问器方法,则spring会自动注入.
Source.java
  1. package com.gary.test;
  3. public class Source {
  5. public void helloWorld(){
  6. System.out.println("Hello World!");
  7. }
  8. }
Target.java
  1. package com.gary.test;
  3. public class Target {
  5. private Source source;
  7. public void setSource(Source source) {
  8. this.source = source;
  9. }
  11. public Source getSource() {
  12. return source;
  13. }
  15. public void sayHelloWorld(){
  16. getSource().helloWorld();
  17. }
  19. }
applicationContext.xml
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <beans
  3. xmlns="http://www.springframework.org/schema/beans"
  4. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  5. xmlns:p="http://www.springframework.org/schema/p"
  6. xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"
  7. default-autowire="byType">
  9. <bean id="source" class="com.gary.test.Source" />
  10. <bean id="target" class="com.gary.test.Target">
  11. <!-- 在beans标签添加default-autowire="byType"属性后,下面这行可以省略 -->
  12. <!-- <property name="source" ref="source" /> -->
  13. </bean>
  14. </beans>
TargetTest.java
 
  1. package com.gary.test;
  3. import org.junit.AfterClass;
  4. import org.junit.BeforeClass;
  5. import org.junit.Test;
  6. import org.springframework.beans.factory.BeanFactory;
  7. import org.springframework.context.support.ClassPathXmlApplicationContext;
  9. public class TargetTest {
  11. static BeanFactory factory = null;
  12. static Target target = null;
  14. @BeforeClass
  15. public static void setUpBeforeClass() throws Exception {
  16. try{
  17. factory = new ClassPathXmlApplicationContext("applicationContext.xml");
  18. target = (Target) factory.getBean("target");
  19. }catch(Exception e){
  20. e.printStackTrace();
  21. }
  22. }
  24. @AfterClass
  25. public static void tearDownAfterClass() throws Exception {
  27. }
  29. @Test
  30. public void testSayHelloWorld() {
  31. target.sayHelloWorld();
  32. }
  34. }
 
三、接口方式注入(不推荐使用)
 
 
通过接口方式注入
建议使用前两种方法
Source.java
  1. package com.gary.test;
  3. public class Source {
  5. public void helloWorld(){
  6. System.out.println("Hello World!");
  7. }
  8. }
ISource.java
  1. package com.gary.test;
  3. public interface ISource {
  4. //方法名任意,方法参数是所依赖对象的类型
  5. public void injectSource(Source source);
  6. }
Target.java
 
  1. package com.gary.test;
  3. public class Target implements ISource{
  5. private Source source;
  7. @Override
  8. public void injectSource(Source source) {
  9. this.source = source;
  10. }
  12. public void sayHelloWorld(){
  13. source.helloWorld();
  14. }
  16. }
applicationContext.xml
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <beans
  3. xmlns="http://www.springframework.org/schema/beans"
  4. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  5. xmlns:p="http://www.springframework.org/schema/p"
  6. xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd"
  7. default-autowire="byType">
  9. <bean id="source" class="com.gary.test.Source" />
  10. <bean id="target" class="com.gary.test.Target" />
  11. </beans>
TargetTest.java
 
  1. package com.gary.test;
  3. import org.junit.AfterClass;
  4. import org.junit.BeforeClass;
  5. import org.junit.Test;
  6. import org.springframework.beans.factory.BeanFactory;
  7. import org.springframework.context.support.ClassPathXmlApplicationContext;
  9. public class TargetTest {
  11. static BeanFactory factory = null;
  12. static Source source = null;
  13. static Target target = null;
  15. @BeforeClass
  16. public static void setUpBeforeClass() throws Exception {
  17. try{
  18. factory = new ClassPathXmlApplicationContext("applicationContext.xml");
  19. target = (Target) factory.getBean("target");
  20. source = (Source) factory.getBean("source");
  21. }catch(Exception e){
  22. e.printStackTrace();
  23. }
  24. }
  26. @AfterClass
  27. public static void tearDownAfterClass() throws Exception {
  29. }
  31. @Test
  32. public void testSayHelloWorld() {
  33. target.injectSource(source);
  34. target.sayHelloWorld();
  35. }
  37. }