优秀的设计模式示例－静态代理模式

package com.eduask.proxy.common; import java.io.Serializable; import org.hibernate.HibernateException; import org.hibernate.Session; import org.hibernate.Transaction; /** * Helper访问组件的代理类 * * @author FrankChen * */ public class HBHelperProxy implements IHelper{ // 被代理对象 private IHelper helper; private boolean isAutoCommit = true; public void setAutoCommit(boolean isAutoCommit) { this.isAutoCommit = isAutoCommit; } public HBHelperProxy(IHelper helper) { this.helper = helper; } public Session getSession() { return this.helper.getSession(); } public Object findByPrimaryKey(Class clazz, Serializable id) { if (getSession() == null || !getSession().isOpen()) return null; return this.helper.findByPrimaryKey(clazz, id); } public void save(Object o) { if (getSession() == null || !getSession().isOpen()) return; if(!this.isAutoCommit) { this.helper.save(o); return; } Transaction tran = getSession().beginTransaction(); try { this.helper.save(o); tran.commit(); } catch (HibernateException he) { tran.rollback(); } } public void update(Object o) { if (getSession() == null || !getSession().isOpen()) return; if(!this.isAutoCommit) { this.helper.update(o); return; } Transaction tran = getSession().beginTransaction(); try { this.helper.update(o); tran.commit(); } catch (HibernateException he) { tran.rollback(); } } public void remove(Object o) { if (getSession() == null || !getSession().isOpen()) return; if(!this.isAutoCommit) { this.helper.remove(o); return; } Transaction tran = getSession().beginTransaction(); try { this.helper.remove(o); tran.commit(); } catch (HibernateException he) { tran.rollback(); } } public void close() { this.helper.close(); } }