7

解き方がわからないというちょっとした問題があります。私を手伝ってくれますか?エンティティを永続化しようとすると、次の例外が発生します:

12:47:39,398 ERROR [org.black.dmitriy.entityHome.ScheduleHome] (http--127.0.0.1-8080-1)  javax.persistence.EntityExistsException: a different object with the same identifier value was already associated with the session: [org.black.dmitriy.entity.Schedule#1]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1333) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1289) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1295) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:859) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_04]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_04]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_04]
at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_04]
at org.jboss.seam.persistence.EntityManagerInvocationHandler.invoke(EntityManagerInvocationHandler.java:46) [jboss-seam.jar:2.3.0.Final]
at $Proxy81.persist(Unknown Source) at org.jboss.seam.framework.EntityHome.persist(EntityHome.java:84) [jboss-seam.jar:2.3.0.Final]
at org.black.dmitriy.entityHome.ConversationHome.tryPersist(ConversationHome.java:147) [ejb.jar:]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_04]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_04]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_04]
at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_04]
at org.jboss.seam.util.Reflections.invoke(Reflections.java:22) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.RootInvocationContext.proceed(RootInvocationContext.java:32) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:56) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.transaction.RollbackInterceptor.aroundInvoke(RollbackInterceptor.java:28) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.core.ConversationInterceptor.aroundInvoke(ConversationInterceptor.java:65) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.transaction.TransactionInterceptor$1.work(TransactionInterceptor.java:97) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.util.Work.workInTransaction(Work.java:61) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.transaction.TransactionInterceptor.aroundInvoke(TransactionInterceptor.java:91) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.core.MethodContextInterceptor.aroundInvoke(MethodContextInterceptor.java:44) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.RootInterceptor.invoke(RootInterceptor.java:107) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.JavaBeanInterceptor.interceptInvocation(JavaBeanInterceptor.java:186) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.intercept.JavaBeanInterceptor.invoke(JavaBeanInterceptor.java:104) [jboss-seam.jar:2.3.0.Final]
at org.black.dmitriy.entityHome.ScheduleHome_$$_javassist_seam_8.tryPersist(ScheduleHome_$$_javassist_seam_8.java) [ejb.jar:]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_04]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_04]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_04]
at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_04]
at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:335) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6]
at org.jboss.el.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:348) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6]
at org.jboss.el.parser.AstPropertySuffix.invoke(AstPropertySuffix.java:58) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6]
at org.jboss.el.parser.AstValue.invoke(AstValue.java:96) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6]
at org.jboss.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:276) [jboss-el-1.0_02.CR6.jar:1.0_02.CR6]
at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:60) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.IdentityFilter.doFilter(IdentityFilter.java:40) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:90) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:45) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.web.HotDeployFilter.doFilter(HotDeployFilter.java:53) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69) [jboss-seam.jar:2.3.0.Final]
at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158) [jboss-seam.jar:2.3.0.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:397) [jbossweb-7.0.13.Final.jar:]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_04]

私はシーム 2.3、休止状態を使用します。import.sql ファイルに挿入ステートメントが 1 つあります。

INSERT INTO Schedules (id, name, dayCount, lessonCount, firstTermSize, secondTermSize, subgroupSize) VALUES(1, '2012/2013', 5, 8, 9, 9, 18)

これにより、1 つのエンティティがテーブル Schedules に挿入されます。

次に、EntityHome を使用して新しい Schedule エンティティ スロー Web ページを作成します。

@Name("scheduleHome")
@Scope(ScopeType.CONVERSATION)
public class ScheduleHome extends ConversationHome<Schedule> {
    private static final long serialVersionUID = 1L;

    public ScheduleHome() {
    }

    @Override
    protected boolean isUnique() {
        Schedule schedule = getInstance();
        Schedule foundSchedule = ScheduleDAO.instance().getByName(schedule.getName());

        if ((foundSchedule != null) && (!foundSchedule.equals(schedule))) {
            showExistsErrorMessage(getInstance().getName());
            return false;
        }

        return true;
    }

    @Override
    protected Schedule createInstance() {
        return new Schedule();
    }

    @Override
    public String getEditOutcome() {
        return "scheduleEdit";
    }

    @Override
    protected void prepareEntityForSaving() {

    }
}

そしてスーパークラス

public abstract class ConversationHome<T> extends EntityHome<T> {
    private static final long serialVersionUID = 1L;
    private String parentView;

    public boolean isParentViewExists() {
        return parentView != null && parentView.length() > 0;
    }

    public void setParentView(String parentView) {
        this.parentView = parentView;
    }

    public String getParentView() {
        return parentView;
    }

    public abstract String getEditOutcome();

    protected abstract void prepareEntityForSaving();

    protected abstract boolean isUnique();

    @Override
    @Create
    public void create() {
        create(false);
    }

    protected void create(boolean createNestedConversation) {
        Conversation conversation = Conversation.instance();
        if (!createNestedConversation && conversation.isLongRunning()) {
            getLog().debug("conversation already started, nested will not create(isLongRunning = #0, isNested = #1)", conversation.isLongRunning(), conversation.isNested());
        } else {
            conversation.begin(false, conversation.isLongRunning());
            conversation.changeFlushMode(FlushModeType.MANUAL);
            getLog().debug("create(isLongRunning = #0, isNested = #1, id = #2)", conversation.isLongRunning(), conversation.isNested(), conversation.getId());
        }
        super.create();
    }

    private boolean init(Long id) {
        FacesContext context = FacesContext.getCurrentInstance();
        setParentView(Pages.getViewId(context));

        if (id != null) {
            setId(id);
            try {
                getInstance();
                getLog().debug("instance initialized #0", getInstance());
            } catch (EntityNotFoundException e) {
                getLog().error(e);
                return false;
            }
        }
        return true;
    }

    public String startEdit(Long id) {
        getLog().debug("start editing #0", id);
        if (init(id)) {
            return getEditOutcome();
        } else {
            return cancel();
        }
    }

    public String cancel() {
        if (isManaged()) {
            getEntityManager().refresh(getInstance());
        }
        return returnToParent();
    }

    @End
    protected String returnToParent() {
         if (isParentViewExists()) {
                Conversation conversation = Conversation.instance();
                getLog().debug("end conversation(id = #0, isLongRunning = #1, isNested = #2)",
                        conversation.getId(), conversation.isLongRunning(), conversation.isNested());
                conversation.end(true);
                return getParentView();
            } else {
                clearInstance();
                return null;
            }
    }

    public String tryPersist() {
        if (isUnique()) {
            try {
                prepareEntityForSaving();

                String outcome = persist();
                if (!"failed".equals(outcome)) {
                    return returnToParent();
                }
            } catch (Exception e) {
                getLog().error(getInstance(), e);
                showSaveErrorMessage(e);
            }
        }
        return "failed";
    }
}

そして、それを永続化しようとすると、この例外が発生します。とウェブページのメッセージ

メッセージを含む保存エラー: 同じ識別子値を持つ別のオブジェクトが既にセッションに関連付けられていました: [org.black.dmitriy.entity.Schedule#1]

hibernate が id プロパティを 1 に設定しているid = 1ように見えますが、手動で作成して import.sql をスローしたため、既に のエンティティがあります。

ここに私のスケジュールエンティティがあります:

import java.util.ArrayList;
import java.util.List;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;

@Entity
@Table(name = "Schedules")
public class Schedule {

    @Id
    @GeneratedValue
    @Column(name = "id", nullable = false)
    private Long id;

    @NotNull
    @Column(name = "name", nullable = false, length = 40)
    private String name;

    @Column(name = "dayCount")
    private int dayCount = 5;

    @Column(name = "lessonCount")
    private int lessonCount = 8;

    @Column(name = "firstTermSize")
    private int firstTermSize = 9;

    @Column(name = "secondTermSize")
    private int secondTermSize = 9;

    @Column(name = "subgroupSize")
    private int subgroupSize = 18;

    @OneToMany(mappedBy = "schedule", cascade = CascadeType.ALL, targetEntity = Faculty.class)
    private List<Faculty> faculties = new ArrayList<>();

    @OneToMany(mappedBy = "schedule", cascade = CascadeType.ALL, targetEntity = Building.class)
    private List<Building> buildings = new ArrayList<>();

    public Schedule() {

    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getDayCount() {
        return dayCount;
    }

    public void setDayCount(int dayCount) {
        this.dayCount = dayCount;
    }

    public int getLessonCount() {
        return lessonCount;
    }

    public void setLessonCount(int lessonCount) {
        this.lessonCount = lessonCount;
    }

    public int getFirstTermSize() {
        return firstTermSize;
    }

    public void setFirstTermSize(int firstTermSize) {
        this.firstTermSize = firstTermSize;
    }

    public int getSecondTermSize() {
        return secondTermSize;
    }

    public void setSecondTermSize(int secondTermSize) {
        this.secondTermSize = secondTermSize;
    }

    public int getSubgroupSize() {
        return subgroupSize;
    }

    public void setSubgroupSize(int subgroupSize) {
        this.subgroupSize = subgroupSize;
    }

    public List<Faculty> getFaculties() {
        return faculties;
    }

    public void setFaculties(List<Faculty> faculties) {
        this.faculties = faculties;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((id == null) ? 0 : id.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (!(obj instanceof Schedule)) {
            return false;
        }
        Schedule other = (Schedule) obj;
        if (id == null) {
            if (other.id != null) {
                return false;
            }
        } else if (!id.equals(other.id)) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return this.name;
    }
}

ご覧のとおり、id プロパティに @GeneratedValue アノテーションがあるため、休止状態は自分で id を生成し、休止状態はデータベースに id = 1 のエンティティがあり、新しいエンティティに id を設定することを知っている必要があると思います = 2.しかし、休止状態は id を設定します新しいエンティティで 1 に変更してください。

4

2 に答える 2

17

問題は、hibernate が を生成する方法idで、1 から始まります。オブジェクトをデータベースに保存する前にオブジェクトに 1 を割り当てると、同じ ID を持つ行がデータベースに既に存在することがわかり、例外が発生します。この問題の単純で自然な解決策は、単純に休止状態を制限することです。これ1により、関連するクラスのオブジェクトに ID として割り当てることができなくなります (あなたの場合)。

mySql のソリューション:

mySql を使用している場合は、テーブルを手動で作成し、次のように自動インクリメントを設定できます。

  CREATE TABLE IF NOT EXISTS `testTable` (
      `id` number(11) NOT NULL AUTO_INCREMENT,
       ...,
       ...,
       ...,
       PRIMARY KEY (`id`)
 ) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=2; //assigning id by hibernate, will start from 2.

また、ドメイン クラスでは、次のように id に注釈を付けることができます。

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "ID")
public long getId() {
   ....
}

GenerationType.AUTOデフォルトでは、mySql で自動インクリメントを使用します。休止状態を設定すると、 AUTO_INCREMENT=2id の割り当てが開始されます2(したがって1、スキップされます)。

オラクルのソリューション:

休止状態で「シーケンス」の使用を制限し、シーケンスの開始点を希望どおりに設定すると、オラクルでも同じことができます。2次のように開始してインクリメントするシーケンスを作成できます1

 create sequence idSequence
        start with 2
        increment by 1
        maxvalue 9999999999999;

また、次のように、ドメイン クラスのオブジェクトの ID を生成するために使用するシーケンスを指定できます。

@Id
@SequenceGenerator(name = "idGeneratorSeq", sequenceName = "idSequence")
@GeneratedValue(strategy = GenerationType.AUTO, generator = "idGeneratorSeq")
@Column(name = "ID")
public long getId() {
   ....
}

そして、あなたの問題は解決されました。

于 2012-12-10T18:25:12.050 に答える
0

メソッドを呼び出す前に、次の手順を実行しますpersist()

最初に現在のインスタンスをデタッチします

getEntityManager().detach(getInstance());

今それIdをnullに設定します

getInstance().setId(null);

今は固執する

String outcome = persist();
于 2012-12-07T13:05:51.253 に答える