Spring由构造方法自动装配

 package com.yiibai.common;
public class Developer {
    private Language language;
    //autowire by constructor
    public Developer(Language language) {
        this.language = language;
    }
    //...
}

package com.yiibai.common;
public class Language {
    private String name;
    //...
}

Spring装配

第一种
 <bean id="developer" class="com.yiibai.common.Developer">
        <constructor-arg>
            <ref bean="language" />
        </constructor-arg>
</bean>
<bean id="language" class="com.yiibai.common.Language" >
    <property name="name" value="Java" />
</bean>
第二种
<bean id="developer" class="com.yiibai.common.Developer" autowire="constructor" />
    <bean id="language" class="com.yiibai.common.Language" >
        <property name="name" value="Java" />
    </bean>