Java 系列之spring学习--依赖注入（二）

一、依赖注入的三种方式

　　接口注入，set注入，构造函数注入

二、构造函数注入

　　2.1、测试类

package test;
 
public class test01 {
 
    public String msg=null;
    public test01(String msg)
    {
        System.out.println(msg);
         
    }
    public void prints()
    {
         
        System.out.println("prints");
    }
}

　　　2.2、编辑applicationContext.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" xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/mvc 
       http://www.springframework.org/schema/mvc/spring-mvc.xsd 
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context.xsd 
       http://www.springframework.org/schema/aop 
       http://www.springframework.org/schema/aop/spring-aop.xsd 
       http://www.springframework.org/schema/tx 
       http://www.springframework.org/schema/tx/spring-tx.xsd
       ">
    
   <!-- 构造函数注入 -->
    <bean id="test01" class="test.test01">
    <constructor-arg index="0">
            <value>dirk</value>
    </constructor-arg>
     <constructor-arg index="1">
            <value>dirk2</value>
    </constructor-arg>
    </bean> 
    
</beans>

　　　2.3、测试　

package test;
 
public class test01 {
 
    public String msg=null;
    public String msg1=null;
    public test01(String msg,String msg1)
    {
        System.out.println(msg+msg1);
         
    }
    public void prints()
    {
         
        System.out.println("prints");
    }
}

package test;
 
import java.io.IOException;
import java.io.PrintWriter;
 
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
 
public class aservlet extends HttpServlet {
 
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
        ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");
        test02 test01=(test02)context.getBean("test02");
        test01.getMsg();
    }
 
}

三、set注入　　

　　3.1测试类

package test;
 
public class test02 {
    public String msg;
 
    public String getMsg() {
        return msg;
    }
 
    public void setMsg(String msg) {
        this.msg = msg;
    }
}

　3.2、配置文件修改　

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/mvc 
       http://www.springframework.org/schema/mvc/spring-mvc.xsd 
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context.xsd 
       http://www.springframework.org/schema/aop 
       http://www.springframework.org/schema/aop/spring-aop.xsd 
       http://www.springframework.org/schema/tx 
       http://www.springframework.org/schema/tx/spring-tx.xsd
       ">
    
  
    <bean id="test02" class="test.test02">
        <property name="msg">
            <value>drik.wang</value>
        </property>
    </bean>
</beans>

package test;
 
import java.io.IOException;
import java.io.PrintWriter;
 
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
 
public class aservlet extends HttpServlet {
 
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
        ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");
        test02 test01=(test02)context.getBean("test02");
        test01.getMsg();
    }
 
}

　　3.3、测试

package test;
 
import java.io.IOException;
import java.io.PrintWriter;
 
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
 
public class aservlet extends HttpServlet {
 
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
        ApplicationContext context=new ClassPathXmlApplicationContext("applicationContext.xml");
        test02 test02=(test02)context.getBean("test02");
        System.out.println(test02.getMsg());    
    }
 
}