Spring4.0的新特性我们在上一章已经介绍过了。包括它对jdk8的支持,Groovy Bean Definition DSL的支持,核心容器功能的改进,Web开发改进,测试框架改进等等。这张我们主要介绍spring4.0的自动扫描功能,以及对bean的过滤等特性进行学习。
好吧,废话少说,我们来看看代码吧。
package com.herman.ss.test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.herman.ss.action.TestAction; import com.herman.ss.filter.Filter1; import com.herman.ss.filter.Filter2; import com.herman.ss.filter.test.Filter3; import com.herman.ss.pojo.House; import com.herman.ss.pojo.Person; /** * @see spring4.0.0最新稳定版新特性,自动扫描bean,自动注入bean * @author Herman.Xiong * @date 2014年7月18日14:49:42 */ public class Test1 { /** * @see spring4.0自动扫描bean,自动注入bean */ public static void test0(){ //1.加载配置文件 ApplicationContext ctx=new ClassPathXmlApplicationContext("com/herman/ss/config/applicationContext1.xml"); //2.获取bean实例 Person person=(Person)ctx.getBean("person"); House house=(House)ctx.getBean("house"); //3.打印bean属性 System.out.println(person); System.out.println(house); } /** * @see spring4.0简单业务逻辑的注解 */ public static void test1(){ //1.加载配置文件 ApplicationContext ctx=new ClassPathXmlApplicationContext("com/herman/ss/config/applicationContext1.xml"); //2.获取bean实例 获取bean TestAction testAction=(TestAction)ctx.getBean("testAction"); //3.打印bean属性 System.out.println(testAction); //4.调用bean对象的方法 testAction.testAction(); //@Service 用于标注业务层组件; //@Repository 用于标注数据访问层组件; //@Controller 用于标注控制层组件(如:Struts中的action) //@Component 表示泛型组件,当组件不好归类的时候,我们可以使用这个组件进行注解。 } /** * @see spring4.0简单注解的排除过滤器配置 */ public static void test2(){ //1.加载配置文件 ApplicationContext ctx=new ClassPathXmlApplicationContext("com/herman/ss/config/applicationContext1.xml"); //2.获取bean实例,只能根据bean的id获取bean Filter1 filter1=(Filter1)ctx.getBean("filter1"); Filter2 filter2=(Filter2)ctx.getBean("filter2"); //3.打印bean属性 System.out.println(filter1); System.out.println(filter2); /** * 运行会报错:Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'filter2' is defined * 原因是:filter2被我们排除在外了,不会自动注入 * 因此会抛异常 */ } /** * @see spring4.0简单注解的包含过滤器配置 */ public static void test3(){ //1.加载配置文件 ApplicationContext ctx=new ClassPathXmlApplicationContext("com/herman/ss/config/applicationContext1.xml"); //2.获取bean实例 Filter3 filter3=(Filter3)ctx.getBean("filter3"); Filter2 filter2=(Filter2)ctx.getBean("filter2"); Filter1 filter1=(Filter1)ctx.getBean("filter1"); //3.打印bean属性 System.out.println(filter3); System.out.println(filter2); System.out.println(filter1); /** * 运行会报错:Exception in thread "main" org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'filter2' is defined * 原因:filter2 被我们排除在外了 * 因此:我们回去filter2 这个bean对象的时候就会报错。 * filter1 为什么不报错呢,因为我们设置了 com.herman.ss.filter包下面的use-default-filters="true" 自动导入 * 因此:filter1 不会报错 */ } public static void main(String[] args) { /** * 注解需要的jar包列举: * spring-aop-4.0.6.RELEASE.jar * spring-beans-4.0.6.RELEASE.jar * spring-context-4.0.6.RELEASE.jar * spring-core-4.0.6.RELEASE.jar * spring-expression-4.0.6.RELEASE.jar * commons-lang-2.4.jar */ //test0(); //test1(); //test2(); test3(); } }配置文件源码:
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" 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-4.0.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-4.0.xsd"> <!-- 打开Spring组件自动扫面,并配置要扫描的基本包 --> <context:component-scan base-package="com.herman.ss.pojo"></context:component-scan> <context:component-scan base-package="com.herman.ss.action"></context:component-scan> <context:component-scan base-package="com.herman.ss.biz"></context:component-scan> <context:component-scan base-package="com.herman.ss.dao"></context:component-scan> <context:component-scan base-package="com.herman.ss.filter" use-default-filters="false"> <!-- 取消自动注入,配置只注入com.herman.ss.filter.test下面的所有类 --> <context:include-filter type="regex" expression="com.herman.ss.filter.test.*"/> </context:component-scan> <context:component-scan base-package="com.herman.ss.filter" use-default-filters="true"> <!-- 自动注入,但是Filter2除外 --> <context:exclude-filter type="regex" expression="com.herman.ss.filter.Filter2" /> </context:component-scan> <!-- 注:<context:component-scan>节点用于通知Spring容器扫描组件,base-package属性用于指定将要被扫描的组件所在的包名 这里将自动的配置扫描com.herman.ss.pojo下面的bean --> </beans>实体类源码:
package com.herman.ss.pojo; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Component; /** * @see 实体类使用Component注解 * @author Herman.Xiong * @date 2014年7月24日17:11:59 */ @Component("person") public class Person { private String name; private int age; //这里设置自动注入 @Autowired private House house; 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 House getHouse() { return house; } public void setHouse(House house) { this.house = house; } public Person() { super(); } public Person(String name, int age) { super(); this.name = name; this.age = age; } public Person(String name, int age, House house) { super(); this.name = name; this.age = age; this.house = house; } @Override public String toString() { return "Person [age=" + age + ", house=" + house + ", name=" + name + "]"; } }House.java源码:
package com.herman.ss.pojo; import org.springframework.stereotype.Component; @Component("house") public class House { private String name; private String address; private float price; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public float getPrice() { return price; } public void setPrice(float price) { this.price = price; } public House() { super(); } public House(String name, String address, float price) { super(); this.name = name; this.address = address; this.price = price; } public String toString() { return "House [address=" + address + ", name=" + name + ", price=" + price + "]"; } }
package com.herman.ss.action; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import com.herman.ss.biz.TestBiz; /** * @see 模拟action * @author Herman.Xiong * @date 2014年7月24日17:17:16 * @since jdk 1.6,tomcat 6.0 */ @Controller("testAction") public class TestAction { //使用自动载入 @Autowired private TestBiz testBiz; //必须提供set方法 public void setTestBiz(TestBiz testBiz) { this.testBiz = testBiz; } public TestAction(){ System.out.println("模拟的action类"); } public void testAction(){ testBiz.testBiz(); } }
package com.herman.ss.biz; /** * @see 模拟biz层进行注解 * @author Herman.Xiong * @date 2014年7月24日17:20:25 */ public interface TestBiz { void testBiz(); }
package com.herman.ss.biz.impl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import com.herman.ss.biz.TestBiz; import com.herman.ss.dao.TestDao; @Service("testBiz") public class TestBizImpl implements TestBiz{ @Autowired private TestDao testDao; //必须提供set方法 public void setTestDao(TestDao testDao) { this.testDao = testDao; } public void testBiz() { System.out.println("模拟biz层"); testDao.testDao(); } }
package com.herman.ss.dao; /** * @see 模拟dao层进行注解 * @author Herman.Xiong * @date 2014年7月24日17:20:25 */ public interface TestDao { void testDao(); }
package com.herman.ss.dao.impl; import org.springframework.stereotype.Repository; import com.herman.ss.dao.TestDao; @Repository("testDao") public class TestDaoImpl implements TestDao{ public void testDao() { System.out.println("模拟dao层"); } }
package com.herman.ss.filter; import org.springframework.context.annotation.Scope; import org.springframework.stereotype.Controller; //Scope注解设置作用域 @Controller("filter1")@Scope("prototype") public class Filter1 { public Filter1(){ System.out.println("我是Filter1 ..."); System.out.println("Scope注解设置作用域"); } }
package com.herman.ss.filter.test; import org.springframework.stereotype.Controller; @Controller("filter3") public class Filter3 { public Filter3(){ System.out.println("我是filter3"); } }
package com.herman.ss.filter; import org.springframework.stereotype.Controller; @Controller("filter2") public class Filter2 { public Filter2(){ System.out.println("我是Filter2 ..."); } }
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