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我需要在Spring/OpenJPA 1應用程序中不允許同時使用相同的確認代碼。我們決定使用select來更新策略，所以我們創建了表AdmissionLock（id，Confirmation_Code，Terminal）。
單獨的示例JDBC應用程序可以很好地與此策略配合使用。它允許同時處理不同的確認碼，並且不允許同時處理相同的確認碼。請參閱下面的示例代碼：如何在Spring/OpenJPA 1中重新創建select更新行鎖定1
線程代碼：
conn.setAutoCommit(false);
long retId = Util.lockBySelectUpdate(conn, threadName, terminalCode, confNumber);
Util.updateConfCode(conn, threadName, terminalCode, confNumber);
conn.commit();
主程序代碼：
String confCode1 = "21";
String confCode2 = "22";
String terminalCode1 = "10";
String terminalCode2 = "11";
Connection conn1 = Util.getNewConnection();
Connection conn2 = Util.getNewConnection();
AdmissionThread admissionThread1=new AdmissionThread(terminalCode1, conn1, confCode1, "Thread1", 10);
AdmissionThread admissionThread2=new AdmissionThread(terminalCode2, conn2, confCode2, "Thread2", 0);
admissionThread1.start();
Thread.sleep(2000);
admissionThread2.start();
SQL：
"SELECT * FROM ADMISSIONLOCK WHERE CONFIRMATION_CODE=? FOR UPDATE"
"update ADMISSIONLOCK set CONFIRMATION_CODE=? where TERMINAL_SERIAL_NUMBER=?;";
由於我們的應用程序是春/ OpenJPA的1我需要在Spring/OPenJPA 1代碼中加入這個想法。所以，我創建了這個簡化代碼的服務：
@Transactional
public void processAdmissionLock (String terminalSerialNumber, String confirmationCode){
AdmissionLock admissionLock = new AdmissionLock(terminalSerialNumber, confirmationCode);
query = entityManager.createNativeQuery(SQL_LOCK_STRING);
entityManager.lock(admissionLock, LockModeType.READ);
query.setParameter(1, confirmationCode).getResultList();
if(isEntityPersistent(admissionLock)) {
admissionLock = entityManager.merge(admissionLock);
} else {
entityManager.persist(admissionLock);
}
}
AdmissionLock實體：
@Entity
@Table (name = SdiAdmissionLock.TABLE_NAME)
public class SdiAdmissionLock extends AbstractEntityImpl {
private static final long serialVersionUID = 1L;
private long uidpk;
private String terminalSerialNumber;
private String confirmationCode;
private Date createdDate;
public static final String TABLE_NAME = "SDIADMISSIONLOCK";
...
}
我的問題是，這個代碼不作任何鎖定。兩個具有相同驗證碼的同時線程都通過