spring中事务重复提交的问题，不知道如何解决

Question

以下是我对事务处理写的代码：
transactionManager = (PlatformTransactionManager) super.getApplicationContext().getBean(
ProjectConstants.TRANSACTIONMANAGER);
DefaultTransactionDefinition def = new DefaultTransactionDefinition();
def.setPropagationBehavior(DefaultTransactionDefinition.PROPAGATION_REQUIRED);
def.setIsolationLevel(DefaultTransactionDefinition.ISOLATION_READ_COMMITTED);
TransactionStatus status = transactionManager.getTransaction(def);
try {
executeTransaction(context);
transactionManager.commit(status);
} catch (ValidationException e) {
transactionManager.rollback(status);
logger.debug("ValidationException:"+e.getMessageKey());
e.printStackTrace();
throw e;
} catch (Exception e) {
logger.error("Exception:" + e.getMessage());
transactionManager.rollback(status);
e.printStackTrace();
throw new BfwException();
}
其中executeTransaction()方法是个抽象方法，由子类实现，当工程发布到正式环境中后，前一两天事务是正常的，但是到了后来就会经常出现事务重复提交的错误，错误如下：
Exception:Transaction has been rolled back because it has been marked as rollback-only
nested exception is org.springframework.transaction.IllegalTransactionStateException: Transaction is already completed - do not call commit or rollback more than once per transaction
org.springframework.transaction.IllegalTransactionStateException: Transaction is already completed - do not call commit or rollback more than once per transaction
at org.springframework.transaction.support.AbstractPlatformTransactionManager.rollback(Unknown Source)
好像是说事务已经提交或回滚过一次了，但是我实在找不出原因，代码里我写的是出异常就回滚，否则就提交啊，请大家帮帮忙，非常感谢！！！

Answer 1

首先我觉得有了spring还是用申明式事务比较好
编程式事务的话可以这样
/**
* 获取事务管理器对象
*
* @return 事务管理器
/
protected static PlatformTransactionManager getTransactionManager() {
return (PlatformTransactionManager) getBean("transactionManager");
}
/*
* 开始事务，返回默认属性的事务状态对象。如果需要自定义事务属性，请自己编写类似代码即可。 事务对象定义如下
* DefaultTransactionDefinition td = new DefaultTransactionDefinition(
* TransactionDefinition.PROPAGATION_REQUIRED);
* td.setReadOnly(true);
*
* @return 事务状态对象
*/
protected static TransactionStatus beginTransaction() {
DefaultTransactionDefinition td = new DefaultTransactionDefinition(
TransactionDefinition.PROPAGATION_REQUIRED);
// td.setReadOnly(true);
TransactionStatus status = getTransactionManager().getTransaction(td);
return status;
}

调用示例代码：
TransactionStatus status = beginTransaction();
try{
dosomthing...
getTransactionManager().commit(status);
}
catch(youException e){
logger.error("",e);
getTransactionManager().rollback(status);
}