休眠错误：分离的实体传递给持久化

Question

我使用 jax-ws、glassfish 和 hibernate 开发了一个 Web 服务。 我有一个实体：

@Entity
public class CertificateRequest {

    @Id
    @Column(unique=true, nullable = false)
    @GeneratedValue
    private Long ID;

    @Column(nullable = false)
    private Long terminalID;

    @Column(nullable = false)
    private boolean approved;

    @Column(nullable = false)
    private byte[] rawCertificateRequest;

    @Column(nullable = false)
    private String openTerminalKey;

    @Column(nullable = false)
    private Date requestDate;

    public Long getID() {
        return ID;
    }

    protected CertificateRequest(){
        this.requestDate = new Date();
    }

    public CertificateRequest(long UID, long terminalID, PKCS10 rawCertificateRequest, String openTerminalKey){
        this.ID = UID;
        this.terminalID = terminalID;
        this.rawCertificateRequest = PKCS10toChar(rawCertificateRequest);
        this.openTerminalKey = openTerminalKey;
        this.requestDate = new Date();
        approved = false;
    }

    public CertificateRequest(long UID, long terminalID, byte[] rawCertificateRequest, String openTerminalKey){
        this.ID = UID;
        this.terminalID = terminalID;
        this.rawCertificateRequest = rawCertificateRequest;
        this.openTerminalKey = openTerminalKey;
        this.requestDate = new Date();
        approved = false;
    }

    public Long getTerminalID() {
        return terminalID;
    }

    public void setTerminalID(long terminalID) {
        this.terminalID = terminalID;
    }

    public Boolean isApproved() {
        return approved;
    }

    public void setApproved(boolean approved) {
        this.approved = approved;
    }

    public PKCS10 getRawCertificateRequest(){
        return CharToPKCS10(this.rawCertificateRequest);
    }

    public void setRawCertificateRequest(PKCS10 rawCertificateRequest) {
        this.rawCertificateRequest = PKCS10toChar(rawCertificateRequest);
    }

    public Date getRequestDate() {
        return requestDate;
    }

    public void setRequestDate(Date requestDate) {
        this.requestDate = requestDate;
    }

    public String getOpenTerminalKey() {
        return openTerminalKey;
    }

    public void setOpenTerminalKey(String openTerminalKey) {
        this.openTerminalKey = openTerminalKey;
    }

    private byte[] PKCS10toChar(PKCS10 rawCertificateRequest){
        return  rawCertificateRequest.getEncoded();
    }

    private PKCS10 CharToPKCS10(byte[] rawCharCertificateRequest){
        try {
            return new PKCS10(rawCharCertificateRequest);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }
}

并使用它：

public static void createCertificateRequest(long UID, long terminalID, byte[] rawCertificateRequest){
    CertificateRequest certificateRequest = new CertificateRequest(UID, terminalID, rawCertificateRequest, "tmpString");

    EntityManager entityManager = EntityManagerFabric.getEntityManager();
    entityManager.getTransaction().begin();
    entityManager.persist(certificateRequest);
    entityManager.getTransaction().commit();
}

然后我在运行时遇到错误：

org.hibernate.PersistentObjectException: detached entity passed to persist: org.sigmaps.keyer.models.CertificateRequest
javax.persistence.PersistenceException: org.hibernate.PersistentObjectException: detached entity passed to persist: org.sigmaps.keyer.models.CertificateRequest
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1763)
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1677)
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1683)
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1187)
    at org.sigmaps.keyer.handlers.CertificateHandler.createCertificateRequest(CertificateHandler.java:34)
    at org.sigmaps.keyer.CertificateService.requestCertificate(CertificateService.java:20)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.glassfish.webservices.InstanceResolverImpl$1.invoke(InstanceResolverImpl.java:143)
    at com.sun.xml.ws.server.InvokerTube$2.invoke(InvokerTube.java:149)
    at com.sun.xml.ws.server.sei.SEIInvokerTube.processRequest(SEIInvokerTube.java:88)
    at com.sun.xml.ws.api.pipe.Fiber.__doRun(Fiber.java:1136)
    at com.sun.xml.ws.api.pipe.Fiber._doRun(Fiber.java:1050)
    at com.sun.xml.ws.api.pipe.Fiber.doRun(Fiber.java:1019)
    at com.sun.xml.ws.api.pipe.Fiber.runSync(Fiber.java:877)
    at com.sun.xml.ws.api.pipe.helper.AbstractTubeImpl.process(AbstractTubeImpl.java:136)
    at org.glassfish.webservices.MonitoringPipe.process(MonitoringPipe.java:142)
    at com.sun.xml.ws.api.pipe.helper.PipeAdapter.processRequest(PipeAdapter.java:119)
    at com.sun.xml.ws.api.pipe.Fiber.__doRun(Fiber.java:1136)
    at com.sun.xml.ws.api.pipe.Fiber._doRun(Fiber.java:1050)
    at com.sun.xml.ws.api.pipe.Fiber.doRun(Fiber.java:1019)
    at com.sun.xml.ws.api.pipe.Fiber.runSync(Fiber.java:877)
    at com.sun.xml.ws.api.pipe.helper.AbstractTubeImpl.process(AbstractTubeImpl.java:136)
    at com.sun.enterprise.security.webservices.CommonServerSecurityPipe.processRequest(CommonServerSecurityPipe.java:210)
    at com.sun.enterprise.security.webservices.CommonServerSecurityPipe.process(CommonServerSecurityPipe.java:142)
    at com.sun.xml.ws.api.pipe.helper.PipeAdapter.processRequest(PipeAdapter.java:119)
    at com.sun.xml.ws.api.pipe.Fiber.__doRun(Fiber.java:1136)
    at com.sun.xml.ws.api.pipe.Fiber._doRun(Fiber.java:1050)
    at com.sun.xml.ws.api.pipe.Fiber.doRun(Fiber.java:1019)
    at com.sun.xml.ws.api.pipe.Fiber.runSync(Fiber.java:877)
    at com.sun.xml.ws.server.WSEndpointImpl$2.process(WSEndpointImpl.java:420)
    at com.sun.xml.ws.transport.http.HttpAdapter$HttpToolkit.handle(HttpAdapter.java:687)
    at com.sun.xml.ws.transport.http.HttpAdapter.handle(HttpAdapter.java:266)
    at com.sun.xml.ws.transport.http.servlet.ServletAdapter.handle(ServletAdapter.java:169)
    at org.glassfish.webservices.JAXWSServlet.doPost(JAXWSServlet.java:169)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838)
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544)
    at java.lang.Thread.run(Thread.java:724)
Caused by: org.hibernate.PersistentObjectException: detached entity passed to persist: org.sigmaps.keyer.models.CertificateRequest
    at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:139)
    at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:75)
    at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:811)
    at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:784)
    at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:789)
    at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1181)
    ... 62 more
]]

我不明白为什么会发生这个错误。任何人都可以解释这个错误的含义，并给出解决方法的建议吗？

Answer 1

错误的原因是您正在创建的实体实例已经设置了@Id 字段。具有设置@Id 字段的实体被持久性提供程序视为分离。不会对数据库进行检查，因此实体是否已存在于数据库中并不重要。

通常，应用程序不应该定义 DB id。你应该把它留给提供者。

但是，如果您想使用应用程序生成的 id，例如 UUID，您可以为您的实体添加一个字段。只是不要用@Id 注释它。您可以并且可能应该在 equals 和 hashCode 方法中使用您的应用程序 ID。

Answer 2

persist 用于新值，所以使用merge 代替它，因为它看起来certificateRequest 已经存在