在 Spring 中使用 parent bean 定义.doc

淄博怡源网络科技有限公司如何去映射壹个 parent bean 作为 Spring 的 Bean 定义的壹部分。 我们壹起来看看以下三个类，看它们如何使用 Spring 来映射。view sourceprint?01public abstract class SuperBean 02private int id;03private String name;0405public int getId() 06return id;070809public void setId(int id) 10this.id = id;111213public String getName() 14return name;151617public void setName(String name) 18 = name;19 202122public class SubBean extends SuperBean 23private String newProperty;2425public String getNewProperty() 26return newProperty;272829public void setNewProperty(String newProperty) 30this.newProperty = newProperty;31 323334public class DifferentBean 35private int id;36private String name;37private String myProperty;3839public int getId() 40return id;414243public void setId(int id) 44this.id = id;454647public String getName() 48return name;495051public void setName(String name) 52 = name;535455public String getMyProperty() 56return myProperty;575859public void setMyProperty(String myProperty) 60this.myProperty = myProperty;6162我们开始在 Spring 中来映射它们：view sourceprint?010206070910111213151617181921222324并且现在我们写壹个简单的应用来展示使用这些映射到底会发生什么情况：view sourceprint?01import org.springframework.context.ApplicationContext;02import org.springframework.context.support.ClassPathXmlApplicationContext;0304public class TestClass 05public static void main(String args) 06ApplicationContext context = new ClassPathXmlApplicationContext(new String applicationContext.xml); 07SubBean subBean = (SubBean)context.getBean(subBean);08System.out.printf(ID: %d, Name: %s, Property: %sn,09subBean.getId(), subBean.getName(), subBean.getNewProperty(); 10DifferentBean differentBean = (DifferentBean)context.getBean(differentBean);11System.out.printf(ID: %d, Name: %s, Property: %sn,12differentBean.getId(), differentBean.getName(), differentBean.getMyProperty();1314如果我们运行这个类，会获取如下结果：view sourceprint?1ID: 2, Name: superBean, Property: subBean2ID: 3, Name: superBean, Property: differentBean我们从这个例子中了解到，如果你的 bean 类没有继承别的类，可以使用 parent 属性来映射 parent bean 的定义。壹个必要条件是子类必须与父类保持兼容，也就是说，子类必须具有父类中已经定义过的所有属性。事实上， Spring 官方文档