EJB 中的事务回滚问题大家来帮帮忙？？

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yubaojian0616

悄悄话
发表文章: 24
注册时间: 2004年11月27日 14:51

EJB 中的事务回滚问题大家来帮帮忙？？	2005年03月16日 20:32
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我在开发时
UserTransaction transaction=context.getUserTransaction();
try
{
transaction.begin();
(1) turnToUserID(100,custonerID);//更新数据库成功
(2)turnToOtherUserID(100,customerIDs);//此方法产生异常
transaction.commit();
}catch(Throwable e)
{
try
{
transaction.rollback();
}catch(SystemException se){throw new EJBException("");}
}
可是turnToUserID的更新还成功并不取消更新这是怎么回事啊
我用的是j2sdkee服务器
我把1，2改为 StringBuffer对象str
(1)str.append("aa");
System.out.print(str);
(2)if (true){throw new EJBException("");}
str.append("bb");
System.out.print(str);
还是能输出aa这是怎么回事啊怎么不回滚阿是不是有什么限制还是没用对阿请高手执教

yubaojian0616

悄悄话
发表文章: 24
注册时间: 2004年11月27日 14:51

Re: EJB 中的事务回滚问题大家来帮帮忙？? size=

2005年03月16日 20:59

还是让高手们看看所有代码把
package com.atm;
import javax.ejb.*;
import javax.sql.*;
import javax.naming.*;
import java.sql.*;
import javax.rmi.*;
import javax.transaction.*;
public class ATMBean implements SessionBean
{
private Connection conn;
private PreparedStatement stat;
private String sql;
private SessionContext context;
private String customerID;
private UserTransaction transaction;
public void EJBCreate(String customerID)throws CreateException
{
this.customerID=customerID;
try
{
makeConnection();
}
catch(Exception e)
{
throw new CreateException("连接异常.");
}
}
public void makeConnection()throws Exception
{
InitialContext contexts=new InitialContext();
DataSource source=(DataSource)contexts.lookup("java:comp/env/jdbc/ATMDB");
conn=source.getConnection();
}
public void updateChecking(double d,String customerID)throws Exception
{
sql="update checking set balance=balance+? where customerID=?";
stat=conn.prepareStatement(sql);
stat.setDouble(1,d);
stat.setString(2,customerID);
int i=stat.executeUpdate();
if (i==-1)
{
System.out.print(" "+i+" ");
throw new Exception("更新checking异常.");
}
stat.close();
}
public void updateSaving(double d,String customerIDs)throws SQLException
{
sql="update saving set balance=balance+? where customerID=?";
stat=conn.prepareStatement(sql);
if (d<0)
{
throw new SQLException("e");
}
stat.setDouble(1,d);
stat.setString(2,customerIDs);
int i=stat.executeUpdate();
if (i==-1)
{
throw new SQLException("更新saving异常.");
}
stat.close();
}
public void setSessionContext(SessionContext context)
{
this.context=context;
}
public void EJBRemove()
{
try
{
conn.close();
}
catch(Exception e)
{}
}
public void EJBActivate()
{
try
{
makeConnection();
}
catch(Exception e)
{}
}
public void EJBPassivate()
{
try
{
conn.close();
}
catch(Exception e)
{}
}
public void takeFromChecking(double d)
{
transaction=context.getUserTransaction();
try
{
transaction.begin();
updateChecking(-d,customerID);
updateMachine(-d);
transaction.commit();
}
catch(Exception e)
{
try
{
transaction.rollback();
}
catch(SystemException se)
{
throw new EJBException(se.getMessage());
}
}
}
public void updateMachine(double d)throws Exception
{
sql="update machine set balance=balance+?";
stat=conn.prepareStatement(sql);
stat.setDouble(1,d);
int i=stat.executeUpdate();
if (i==-1)
{
throw new Exception("添加异常.");
}
stat.close();
}
public void takeFromSaving(double d)
{
transaction=context.getUserTransaction();
try
{
transaction.begin();
updateSaving(-d,customerID);
updateMachine(-d);
transaction.commit();
}
catch (Exception e)
{
try
{
System.out.print("你好.");
transaction.rollback();
}
catch (SystemException se)
{
throw new EJBException(se.getMessage());
}
}
}
public void turnFromCheckingToSaving(double d)
{
if (d<0)
{
throw new EJBException("");
}
transaction=context.getUserTransaction();
try
{
transaction.begin();
updateChecking(-d,customerID);
updateSaving(d,customerID);
transaction.commit();
}
catch (Throwable e)
{
try
{
transaction.rollback();
}
catch (SystemException se)
{
throw new EJBException(se.getMessage());
}
}
}
public void turnFromSavingToChecking(double d)
{
if (d<0)
{
throw new EJBException("d");
}
transaction=context.getUserTransaction();
try
{
transaction.begin();
updateChecking(d,customerID);
updateSaving(-d,customerID);
transaction.commit();
}
catch (Exception e)
{
try
{
transaction.rollback();
}
catch (SystemException se)
{
throw new EJBException(se.getMessage());
}
}
}
public void turnToUser(double d,String userID)/*********调用的这个方法************/
{
if (d<0)
{
throw new EJBException("");
}
UserTransaction transactions=context.getUserTransaction();
try
{
transactions.begin();
//conn.setAutoCommit(false);
updateSaving(d,userID);
updateSaving(-d,customerID);
System.out.print("no..");
transactions.commit();
}
catch (Throwable e)
{
try
{
System.out.print("ok..");
transactions.rollback();
System.out.print("ok..");
}
catch (Exception se)
{
System.out.print("ddfdfd");
throw new EJBException(se.getMessage());
}
}
}
public double getBalance()
{
double d=0.0;
transaction=context.getUserTransaction();
try
{
transaction.begin();
double a=getCheckingBalance();
double b=getSavingBalance();
d=a+b;
transaction.commit();
}
catch (Exception e)
{
try
{
transaction.rollback();
}
catch (SystemException se)
{
throw new EJBException(se.getMessage());
}
}
return d;
}
public double getCheckingBalance()throws Exception
{
sql="select balance from checking where customerID=?";
stat=conn.prepareStatement(sql);
stat.setString(1,customerID);
ResultSet rs=stat.executeQuery();
if (rs.next())
{
return rs.getDouble(1);
}
else
{
throw new Exception("aa");
}
}
public double getSavingBalance()throws Exception
{
sql="select balance from saving where customerID=?";
stat=conn.prepareStatement(sql);
stat.setString(1,customerID);
ResultSet rs=stat.executeQuery();
if (rs.next())
{
return rs.getDouble(1);
}
else
{
throw new Exception("bb");
}
}
public String getUsername()
{
String username=null;
sql="select username from user where customerID=?";
try
{
stat=conn.prepareStatement(sql);
stat.setString(1,customerID);
ResultSet rs=stat.executeQuery();
if (rs.next())
{
username=rs.getString(1);
}
stat.close();
}
catch (Exception e)
{
throw new EJBException(e.getMessage());
}
return username;
}
}
//我所调用的是public void turnToUser(double d,String userID)这个方法到底怎么回事啊本来EJB很了解但现在对事物真是不敢说了

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