我们可以假设在JPA的数据库中找不到ParentKey是IllegalStateException吗？

如何知道JPA中未找到的Prent参考

在MyDAO持久化员工记录期间，其他事务/流程将删除该员工的参考部门记录。 当时，我无法捕获PersistenceException。系统抛出java.lang.IllegalStateException。 这就是为什么。我无法从SQLException中检索SQL错误代码

在实体上

@Entity
public class Employee implements Serializable {
    private static final long serialVersionUID = -3661270122068507264L;
    @Id
    private String id;
    private String name;
    @OneToOne
    @JoinColumn(name ="DEPARTMENT_ID", referencedColumnName = "ID")
    private Department department;

    public Employee() {
    }

    //getter setter
}

在我的刀里

public void insert(Employee employee) throws DAOException {
    try {
        em.persist(employee);
        em.flush();
    } catch (PersistenceException pe) {
        throw DAOUtils.translateDAOException(pe);
    }
}

DAOUtils.translateDAOException函数是从PersistenceException获取SQL错误代码的自定义函数

我将描述堆栈跟踪

java.lang.IllegalStateException: During synchronization a new object was found through a relationship that was not marked cascade PERSIST: org.ace.java.support.comp.depar
tment.Department@d769e1ae.
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.discoverAndPersistUnregisteredNewObjects(UnitOfWorkImpl.java:4174)
    at org.eclipse.persistence.mappings.ObjectReferenceMapping.cascadeDiscoverAndPersistUnregisteredNewObjects(ObjectReferenceMapping.java:793)
    at org.eclipse.persistence.mappings.ObjectReferenceMapping.cascadeDiscoverAndPersistUnregisteredNewObjects(ObjectReferenceMapping.java:771)
    at org.eclipse.persistence.internal.descriptors.ObjectBuilder.cascadeDiscoverAndPersistUnregisteredNewObjects(ObjectBuilder.java:1662)
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.discoverAndPersistUnregisteredNewObjects(UnitOfWorkImpl.java:4177)
    at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.discoverUnregisteredNewObjects(RepeatableWriteUnitOfWork.java:289)
    at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.calculateChanges(UnitOfWorkImpl.java:701)
    at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.writeChanges(RepeatableWriteUnitOfWork.java:415)
    at org.eclipse.persistence.internal.jpa.EntityManagerImpl.flush(EntityManagerImpl.java:741)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:240)
    at $Proxy16.flush(Unknown Source)
    at org.ace.java.support.comp.department.persistence.DepartmentDAO.insert(DepartmentDAO.java:26)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:309)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at $Proxy17.insert(Unknown Source)
    at org.ace.java.support.comp.department.service.DepartmentService.addNewEmployee(DepartmentService.java:28)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:309)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at $Proxy18.addNewEmployee(Unknown Source)
    at org.ace.java.support.comp.department.testcase.DepartmentServiceTestCase.testException(DepartmentServiceTestCase.java:116)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.junit.runners.Suite.runChild(Suite.java:128)
    at org.junit.runners.Suite.runChild(Suite.java:24)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:136)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:117)
    at org.junit.runner.JUnitCore.runMain(JUnitCore.java:98)
    at org.junit.runner.JUnitCore.runMainAndExit(JUnitCore.java:53)
    at org.junit.runner.JUnitCore.main(JUnitCore.java:45)
    at org.ace.java.support.comp.department.testcase.DepartmentServiceTestCase.main(DepartmentServiceTestCase.java:124)
E
Time: 13.161
There was 1 failure:
1) testException(org.ace.java.support.comp.department.testcase.DepartmentServiceTestCase)
org.springframework.transaction.TransactionSystemException: Could not commit JPA transaction; nested exception is javax.persistence.RollbackException: Transaction rolled 
back because transaction was set to RollbackOnly.
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:476)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:754)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at $Proxy18.addNewEmployee(Unknown Source)
    at org.ace.java.support.comp.department.testcase.DepartmentServiceTestCase.testException(DepartmentServiceTestCase.java:116)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
    at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.junit.runners.Suite.runChild(Suite.java:128)
    at org.junit.runners.Suite.runChild(Suite.java:24)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:136)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:117)
    at org.junit.runner.JUnitCore.runMain(JUnitCore.java:98)
    at org.junit.runner.JUnitCore.runMainAndExit(JUnitCore.java:53)
    at org.junit.runner.JUnitCore.main(JUnitCore.java:45)
    at org.ace.java.support.comp.department.testcase.DepartmentServiceTestCase.main(DepartmentServiceTestCase.java:124)
Caused by: javax.persistence.RollbackException: Transaction rolled back because transaction was set to RollbackOnly.
    at org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commitInternal(EntityTransactionImpl.java:92)
    at org.eclipse.persistence.internal.jpa.transaction.EntityTransactionImpl.commit(EntityTransactionImpl.java:63)
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:467)
    ... 41 more 

我们是否可以假设，如果java.lang.IllegalStateException异常，则父/引用记录已被其他事务或进程删除？

如果抛出了IllegalStateException，并且您希望捕获它，请执行此操作

try {}
catch (IllegalStateException){}

---

抛出的异常不是PersistenceException的实例，因此不会被捕获。

它抛出一个非法状态异常，因为JPA第3.2.4节要求在未标记为cascade persist或all的关系上同步引用了新实体或移除实体的托管实体时抛出一个异常。没有要解析的SQL，因此您需要捕获IllegalStateException，并以与常规PersistenceException不同的方式处理它

：太赫兹，谢谢你的回答。我的问题是为什么PersistenceProvider抛出PersistenceException…如果您想知道是什么导致了异常，请发布堆栈跟踪。