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ejbcmp实体bean实际上是什么时候创建的

entity-bean cmp ejb persistence sql

1

phunehehe · 技术社区 · 15 年前

public void businessMethod(int number) {
    try {
        MyBeanHome home = lookupMyBean();
        DataSource dataSource = getMyDataSource();
        Statement statement = dataSource.getConnection().createStatement();
        ResultSet result;
        String tableName = "MYBEAN";
        for (int i = 0; i < number; i++) {
            result = statement.executeQuery("select max(ID) + 1 from " + tableName);
            result.next();
            int newID = result.getInt(1);
            System.out.println(newID);
            MyBeanLocal lineLocal = home.create(newID);
        }
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

的创建方法 MyBean 简单地创建一个新bean newID . 但是,上面的代码只适用于 number = 1 . 如果 number > 1 ,它尝试创建具有相同ID的第二个bean( System.out.println(newID);

非常感谢!

1 回复 | 直到 15 年前

1

phunehehe 15 年前

我发现事务只在业务方法完成时执行,因此第一个实体bean不会存储在数据库中进行检索。下面是一个简单的解决方案

public void businessMethod(int number) {
    try {
        MyBeanHome home = lookupMyBean();
        DataSource dataSource = getMyDataSource();
        Statement statement = dataSource.getConnection().createStatement();
        ResultSet result;
        String tableName = "MYBEAN";
        result = statement.executeQuery("select max(ID) + 1 from " + tableName);
        result.next();
        int newID = result.getInt(1);
        for (int i = 0; i < number; i++) {
            System.out.println(newID);
            MyBeanLocal lineLocal = home.create(newID++);
        }
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}