利用Guice的Aop实现切面事务管理
类似于Spring的声明式事务管理，Guice中也可以很容易的实现，这里我拿Guice+Ibatis举个例子。
1. Guice要支持aop，首先我们引入aopalliance.jar。
2. 声明自己的事务annotation
- package com.yingxia.server.common;
- import java.lang.annotation.ElementType;
- import java.lang.annotation.Retention;
- import java.lang.annotation.RetentionPolicy;
- import java.lang.annotation.Target;
- @Target(ElementType.METHOD)
- @Retention(RetentionPolicy.RUNTIME)
- public @interface Transaction {
- }
3. 声明切面事务拦截器TransactionInterceptor
- package com.yingxia.server.common;
- import org.aopalliance.intercept.MethodInterceptor;
- import org.aopalliance.intercept.MethodInvocation;
- public class TransactionInterceptor implements MethodInterceptor {
- @Override
- public Object invoke(MethodInvocation mi) throws Throwable {
- Object obj = null;
- try {
- BaseDao.sqlMapper.startTransaction();
- System.out.println("事务开始");
- obj = mi.proceed();
- BaseDao.sqlMapper.commitTransaction();
- System.out.println("事务提交");
- } finally {
- BaseDao.sqlMapper.endTransaction();
- System.out.println("事务结束");
- }
- return obj;
- }
- }
4. 最后把拦截器绑定到Guice全局的Injector当中。这里请注意静态引入import static。bindInterceptor方法的前两个参数一个是用来过滤类，一个用来过滤方法。好了，这样你所有GuiceRemoteServiceServlet类的子类的带有Transaction标注的方法都将被纳入事务管理了。
Java代码
- private static final Injector injector = Guice.createInjector(new Module() {
- @Override
- public void configure(Binder binder) {
- binder.bindInterceptor(
- subclassesOf(GuiceRemoteServiceServlet.class),
- any(),
- new ExceptionInterceptor()
- );
- binder.bindInterceptor(
- subclassesOf(GuiceRemoteServiceServlet.class),
- annotatedWith(Transaction.class),
- new TransactionInterceptor()
- );
- }
- });
