EJP是一個強大並且便於使用的HTTP://www.aliyun.com/zixun/aggregation/22.html">關係資料庫持久化JAVA API。 EJP的主要特性包括:
1、物件/關係(object/relational)自動映射(A-O/RM)
2、自動處理所有關聯
3、自動持久化跟蹤
EJP不需要映射注釋或XML配置,並且不需要繼承任何類或實現任何介面。 EJP只用到了Plain Old JAVA Objects (POJOs)物件。 到目前為止,EJP是JAVA開源中最簡單的持久化API。
Easy JAVA Persistence 2.4一大特點是加強了與主鍵和外鍵的自動處理,讓他們只需要在代碼中定義需要的地方。 此版本還修復了一批保存物件時的錯誤。
下載位址:HTTP://www.easierjava.com/downloads/ejp_2.4.zip
EJP的應用:
public static void main(String[] args) { DatabaseManager dbm = DatabaseManager.getDatabaseManager(...); dbm.saveObje ct(new Customer("Smith", "John")); Customer customer; if ((customer = dbm.loadObject(new Customer("Smith"))) != null) { customer.getSupport().add(new Support(...)); dbm.saveObject(customer); } Collection<Customer> list = new ArrayList<Customer>(); list = dbm.loadObjects(list, Customer.class); ... }
It's used with normal class definitions like the following:
public class Customer { String firstName, lastName; List<Support> support; List<Order> orders; ... public Customer(String lastName) { this.lastName = lastName; } ... public getFirstName() { return firstName; } public setFirstName(String firstName) { this.firstName = firstName; } public getLastName() { return lastName; } public setLastNam e(String lastName) { this.lastName = lastName; } ... // Associations (automatic) public List<Support> getSupport() { return support; } public void setSupport(List<Support> support) { this.support = support; } public List<Order> getOrders() { r eturn orders; } public void setOrders(List<Order> orders) { this.orders = orders; } ... }