i 想要建立一个简单的 CROUD 控制台应用程序,由需要使用 CROUD 方法的10-20 类组成。我不想每次在需要 db 访问的每一种方法中创建连接。也许将所有创建部件都放入单独的单吨类?
任何想法、如何构建这种应用的最佳做法?
仅一个教程就足够学习 < a href=>" "http://balusc.blogspot.com/2008/07/dao-tutor-tutor-data-layer.html" rel="no follow" > 如何设计 DAO
使用Netbeans JPA向导:
不需要处理连接 。
创建基础类, 以所有功能作为分隔法。 例如, 如下 。
连接获取连接 - 返回连接对象
无效关闭() - 关闭连接
类似每个功能的这个执行方法。 将您的操作类扩展至这个基级, 并调用所需的功能 。
ex :
public class Insert extends Base {
// call the rquired functions
}
需要时,您可以模拟一些变量,如驱动器名、 URL、 用户名、 密码等,
Hi have this j2ee web application developed using spring framework. I have a problem with rendering mnessages in nihongo characters from the properties file. I tried converting the file to ascii using ...
Check this, List<String> list = new ArrayList<String>(); for (int i = 0; i < 10000; i++) { String value = (""+UUID.randomUUID().getLeastSignificantBits()).substring(3, ...
I am in the middle of solving a problem where I think it s best suited for a decorator and a state pattern. The high level setting is something like a sandwich maker and dispenser, where I have a set ...
I have been trying to execute a MS SQL Server stored procedure via JDBC today and have been unsuccessful thus far. The stored procedure has 1 input and 1 output parameter. With every combination I ...
I have a system which contains multiple applications connected together using JMS and Spring Integration. Messages get sent along a chain of applications. [App A] -> [App B] -> [App C] We set a ...
If I m given two Java Libraries in Jar format, 1 having no bells and whistles, and the other having lots of them that will mostly go unused.... my question is: How will the larger, mostly unused ...
I have a Class variable that holds a certain type and I need to get a variable that holds the corresponding array class. The best I could come up with is this: Class arrayOfFooClass = java.lang....
I m working on a Java desktop application that reads and writes from/to different files. I think a better solution would be to replace the file system by a SQLite database. How hard is it to migrate ...