📄 accountbean.java
字号:
package examples.entity.intro;
import javax.ejb.Interceptors;
import javax.ejb.Remote;
import javax.ejb.Stateful;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
import javax.persistence.EntityListener;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;
/**
* Stateful session bean facade for account entities, remotely accessible
*/
@Stateful
@Remote(AccountInterface.class)
public class AccountBean implements AccountInterface {
/** The entity manager, injected by the container */
@PersistenceContext(type=PersistenceContextType.EXTENDED)
private EntityManager manager;
private Account account;
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
public void open(int accountNumber) {
account = manager.find(Account.class, accountNumber);
if(account == null)
account = new Account();
account.ownerName = "anonymous";
account.accountNumber = accountNumber;
manager.persist(account);
}
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
public int getBalance() {
if(account==null)
throw new IllegalStateException();
return account.balance;
}
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
public void deposit(int amount) {
if(account==null)
throw new IllegalStateException();
//manager = emf.createEntityManager(PersistenceContextType.EXTENDED);
//account = manager.merge(account);
account.balance += amount;
//manager.flush();
}
@TransactionAttribute(TransactionAttributeType.REQUIRES_NEW)
public int withdraw(int amount) {
if(account==null)
throw new IllegalStateException();
// manager.lock(account, LockMode.WRITE);
if (amount > account.balance) {
return 0;
} else {
account.balance -= amount;
return amount;
}
}
}
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -