src/org/nutz/trans/Trans.java
public static void rollback() throws Exception {
        Integer c = Trans.count.get();
        if (c == null)
            c = Integer.valueOf(0);
        else if (c > 0)
        	c--;
        Trans._rollback(c);
    }
public static void rollback() throws Exception {
        Integer c = Trans.count.get();
        if (c == null)
            c = Integer.valueOf(0);
        else if (c > 0)
        	c--;
        Trans._rollback(c);
    }
回滚事务，执行它前，你必需保证你已经手工开始了一个事务

@throws Exception