Spring 基于构造函数的依赖注入
当容器调用带有一组参数的类构造函数时，基于构造函数的 DI 就完成了，其中每个参数代表一个对其他类的依赖。
spellchecker.java
public class spellChecker {
public spellChecker(){
System.out.println("spellcheck init");
}
public void check(){
System.out.println(this.getClass().getName());
System.out.println("spellchecker check");
}
}
textEditor.java
public class textEditor {
private spellChecker checker;
public textEditor(spellChecker checker){
System.out.println("textEditor init");
this.checker = checker;
}
public void check(){
System.out.println(this.getClass().getName());
this.checker.check();
}
}
springconfig.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="spellChecker" class="spellChecker"></bean>
<bean id="textEditor" class="textEditor">
<constructor-arg ref="spellChecker"></constructor-arg>
</bean>
</beans>
Spring 基于设值函数的依赖注入
spellchecke.java
public class spellChecker {
public spellChecker(){
System.out.println("spellcheck init");
}
public void check(){
System.out.println(this.getClass().getName());
System.out.println("spellchecker check");
}
}
texteditor.java
public class textEditor {
private spellChecker checker;
public textEditor(){
System.out.println("textEditor init");
}
public void setChecker(spellChecker checker){
this.checker = checker;
}
public void check(){
System.out.println(this.getClass().getName());
this.checker.check();
}
}
springconfig.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="spellChecker" class="spellChecker"></bean>
<bean id="textEditor" class="textEditor">
<property name="checker" ref="spellChecker"></property>
</bean>
</beans>
Spring 注入内部 Beans
Java 内部类是在其他类的范围内被定义的，同理，inner beans 是在其他 bean 的范围内定义的 bean。因此在 或 元素内 元素被称为内部bean
spellcheck.java
public class spellChecker {
public spellChecker(){
System.out.println("inner spellcheck init");
}
public void check(){
System.out.println(this.getClass().getName());
System.out.println("inner spellchecker check");
}
}
textEditor.java
public class textEditor {
private spellChecker spellChecker;
public textEditor(){
System.out.println("textEditor init");
}
public void setSpellChecker(spellChecker spellChecker) {
this.spellChecker = spellChecker;
}
public spellChecker getChecker() {
return spellChecker;
}
public void callcheck(){
System.out.println(this.getClass().getName());
this.spellChecker.check();
}
}
springconfig.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="spellChecker" class="spellChecker"></bean>
<bean id="textEditor" class="textEditor">
<property name="spellChecker">
<bean id="spellChecker" class="spellChecker"></bean>
</property>
</bean>
</beans>
测试
Spring 注入集合
javacollection.java
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
public class javacollection {
private List addlist;
private Set addset;
private Map addmap;
private Properties addprop;
public void setAddlist(List addlist) {
this.addlist = addlist;
}
public List getAddlist() {
return addlist;
}
public void setAddset(Set addset) {
this.addset = addset;
}
public Set getAddset() {
return addset;
}
public void setAddmap(Map addmap) {
this.addmap = addmap;
}
public Map getAddmap() {
return addmap;
}
public void setAddprop(Properties addprop) {
this.addprop = addprop;
}
public Properties getAddprop() {
return addprop;
}
}
springconfig.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="javacollection" class="javacollection">
<property name="addlist">
<list>
<value>india</value>
<value>japan</value>
<value>china</value>
<value>pekke</value>
</list>
</property>
<property name="addset">
<set>
<value>india</value>
<value>japan</value>
<value>china</value>
<value>pekke</value>
</set>
</property>
<property name="addmap">
<map>
<entry key="1" value="india"></entry>
<entry key="2" value="japan"></entry>
<entry key="3" value="china"></entry>
<entry key="4" value="pekke"></entry>
</map>
</property>
<property name="addprop">
<props>
<prop key="one">india</prop>
<prop key="two">japan</prop>
<prop key="three">china</prop>
<prop key="four">pekke</prop>
</props>
</property>
</bean>
</beans>
Spring 注入引用
springconfig.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="javacollection" class="javacollection">
<property name="addlist">
<list>
<ref bean=".."></ref>
<ref bean=".."></ref>
<value>china</value>
<value>pekke</value>
</list>
</property>
<property name="addset">
<set>
<ref bean=".."></ref>
<ref bean=".."></ref>
<value>china</value>
<value>pekke</value>
</set>
</property>
<property name="addmap">
<map>
<entry key="1" value-ref=".."></entry>
<entry key="2" value-ref=".."></entry>
<entry key="3" value="china"></entry>
<entry key="4" value="pekke"></entry>
</map>
</property>
</bean>
</beans>
最后
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