spring 自动装配 可以简化配置熟
两种都在beans标签中配置
1:根据name(id) 来查询bean default-autowire="byName" 不用配置类中的类属性,会根据id去查找,
但是类的对象必须跟id名称保持一致.多用于快速开发,因为看不到继承关系.
2:根据type(class)来查询bean default-autowire="byType" 不用配置类中的雷属性,会根据类的类型去找
类的id可以改变
package zhc.love.dj.test; public class Bean2 { private Bean3 bean3 ; private Bean4 bean4 ; private Bean5 bean5 ; public Bean3 getBean3() { return bean3; } public void setBean3(Bean3 bean3) { this.bean3 = bean3; } public Bean4 getBean4() { return bean4; } public void setBean4(Bean4 bean4) { this.bean4 = bean4; } public Bean5 getBean5() { return bean5; } public void setBean5(Bean5 bean5) { this.bean5 = bean5; } }
package zhc.love.dj.test; public class Bean3 { private int id ; private String name ; private String password ; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
package zhc.love.dj.test; public class Bean4 { private int id ; private String name ; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
package zhc.love.dj.test; public class Bean5 { private int age ; public int getAge() { return age; } public void setAge(int age) { this.age = age; } }
package zhc.love.dj.test; import org.springframework.beans.factory.BeanFactory; import org.springframework.context.support.ClassPathXmlApplicationContext; public class TestCase extends junit.framework.TestCase { public void testSpringAbstract(){ BeanFactory factory = new ClassPathXmlApplicationContext("applicationContext*.xml"); Bean2 bean2 = (Bean2)factory.getBean("bean2"); System.out.println("Bean2.Bean3.id="+ bean2.getBean3().getId()); System.out.println("Bean2.Bean3.name="+ bean2.getBean3().getName()); System.out.println("Bean2.Bean3.password="+ bean2.getBean3().getPassword()); System.out.println("Bean2.Bean4.id="+ bean2.getBean4().getId()); System.out.println("Bean2.Bean4.name="+ bean2.getBean4().getName()); System.out.println("Bean2.Bean5.age="+ bean2.getBean5().getAge()); } }
<?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-2.0.xsd" default-autowire="byType"> <bean id="abstractBean" abstract="true"> <property name="id" value="111"></property> <property name="name" value="chao"></property> </bean> <bean id="bean13" class="zhc.love.dj.test.Bean3" parent="abstractBean"> <property name="password" value="love"></property> </bean> <bean id="bean4" class="zhc.love.dj.test.Bean4" parent="abstractBean"> </bean> </beans>
在配置中不用配置bean2中的其它属性.减少配置
<?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-2.0.xsd" default-autowire="byType" > <bean id="bean2" class="zhc.love.dj.test.Bean2" /> <bean id="bean5" class="zhc.love.dj.test.Bean5"> <property name="age" value="10"></property> </bean> </beans>