java - 已经有关联的托管连接错误-6ren

java - 已经有关联的托管连接错误

转载作者：行者123 更新时间：2023-11-28 22:42:59

根本原因是

org.hibernate.TransactionException: Already have an associated managed connection

如果有人可以帮助我了解问题的原因。请随时询问更多详情。我能想到的一个可能原因是我在其中遇到此异常并执行 @JoinColumn 以连接两个表并显示结果的部分。我应该采取什么预防措施来避免这种情况。

    package com.next.domain;

import static javax.persistence.GenerationType.AUTO;
import static org.apache.commons.lang.builder.EqualsBuilder.reflectionEquals;
import static org.apache.commons.lang.builder.HashCodeBuilder.reflectionHashCode;
import static org.apache.commons.lang.builder.ToStringBuilder.reflectionToString;

import java.io.Serializable;
import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

@Entity
@Table(name="answers")
@XmlRootElement
public class Answer implements Serializable {
    private static final long serialVersionUID = 1L;

    private Long mId;
    private Long mQuizId;

    @Size(max=1000, message="\'Description\' must be less than 1000 characters.")
    private String mContent;

    private Date mRegDate;

    @Id
    @GeneratedValue(strategy = AUTO)
    public Long getId() {
        return mId;
    }

    public void setId(Long id) {
        mId = id;
    }

    @Column(name="quiz_id")
    public Long getQuizId() {
        return mQuizId;
    }

    public void setQuizId(Long quizId) {
        mQuizId = quizId;
    }

    @Column(name="content")
    public String getContent() {
        return mContent;
    }

    public void setContent(String content) {
        mContent = content;
    }

    @Column(name="reg_date")
    public Date getRegDate() {
        return mRegDate;
    }

    public void setRegDate(Date regDate) {
        mRegDate = regDate;
    }

    @Override
    public boolean equals(Object obj) {
        return reflectionEquals(this, obj);
    }

    @Override
    public int hashCode() {
        return reflectionHashCode(this);
    }

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







package com.next.domain;

import static javax.persistence.GenerationType.AUTO;
import static org.apache.commons.lang.builder.EqualsBuilder.reflectionEquals;
import static org.apache.commons.lang.builder.HashCodeBuilder.reflectionHashCode;
import static org.apache.commons.lang.builder.ToStringBuilder.reflectionToString;

import java.io.Serializable;
import java.util.Date;
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.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;

import org.hibernate.validator.constraints.NotEmpty;

@Entity
@Table(name="quizzes")
@XmlRootElement
public class Quiz implements Serializable {
    private static final long serialVersionUID = 1L;

    private Long mId;

    private Integer mSection;

    private Long mAnswerId;

    @NotEmpty(message="\'Title\' must not be empty.")
    @Size(max=64, message="\'Title\' must be less than 64 characters.")
    private String mTitle;

    @Size(max=256, message="\'Question\' must be less than 256 characters.")
    private String mContent;

    @Size(max=256, message="\'Description\' must be less than 256 characters.")
    private String mDescription;

    private List<Answer> mAnswers;

    private Date mRegDate;

    @Id
    @GeneratedValue(strategy = AUTO)
    public Long getId() {
        return mId;
    }

    public void setId(Long id) {
        mId = id;
    }

    @Column(name="section")
    public Integer getSection() {
        return mSection;
    }

    public void setSection(Integer mSection) {
        this.mSection = mSection;
    }

    @Column(name="answer_id")
    public Long getAnswerId() {
        return mAnswerId;
    }

    public void setAnswerId(Long answer_id) {
        mAnswerId = answer_id;
    }

    @Column(name="title")
    public String getTitle() {
        return mTitle;
    }

    public void setTitle(String title) {
        mTitle = title;
    }

    @Column(name="content")
    public String getContent() {
        return mContent;
    }

    public void setContent(String content) {
        mContent = content;
    }

    @Column(name="description")
    public String getDescription() {
        return mDescription;
    }

    public void setDescription(String description) {
        mDescription = description;
    }

    @OneToMany(cascade={CascadeType.MERGE, CascadeType.REMOVE})
    @JoinColumn(name="quiz_id", referencedColumnName="id")
    public List<Answer> getAnswers() {
        return mAnswers;
    }

    public void setAnswers(List<Answer> answers) {
        mAnswers = answers;
    }

    @Column(name="reg_date")
    public Date getRegDate() {
        return mRegDate;
    }

    public void setRegDate(Date regDate) {
        mRegDate = regDate;
    }

    @Override
    public boolean equals(Object obj) {
        return reflectionEquals(this, obj);
    }

    @Override
    public int hashCode() {
        return reflectionHashCode(this);
    }

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







       package com.next.persistence;

    import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.Date;
    import java.util.List;
    import java.util.Map;

    import javax.persistence.EntityManager;
    import javax.persistence.NoResultException;
    import javax.persistence.PersistenceContext;
    import javax.persistence.PersistenceContextType;

    import org.springframework.stereotype.Repository;
    import org.springframework.transaction.annotation.Propagation;
    import org.springframework.transaction.annotation.Transactional;

    import com.next.domain.Answer;
    import com.next.domain.Quiz;
    import com.next.domain.QuizSubmission;

    @Repository("quizDao")
    @Transactional(propagation = Propagation.REQUIRED, rollbackFor = Throwable.class)
    public class QuizDaoImpl implements QuizDao {
        private static final String QUIZ_SELECT_CLAUSE = "select new map(q.id as id, q.title as title, q.regDate as regDate)";
        private static final String ANSWER_SELECT_CLAUSE = "select new map(a.id as id, a.content as content)";

        @PersistenceContext(type=PersistenceContextType.EXTENDED)
        private EntityManager em;

        @Override
        public void addQuiz(Quiz quiz) {
            em.persist(quiz);
        }

        @Override
        public void saveQuiz(Quiz quiz) {
            em.merge(quiz);
        }

        @Override
        public void deleteQuiz(long id) {
            try {
                em.remove(getQuiz(id));
            } catch (IllegalArgumentException ie) {
                return;
            }
        }

        @Override
        public Quiz getQuiz(long id) {
            Quiz quiz = null;

            try {
                quiz = em.find(Quiz.class, id);
            } catch (NoResultException e) {}        

            return quiz;
        }

        @Override
        public void addAnswer(Answer answer) {
            em.persist(answer);
        }

        @Override
        public void saveAnswer(Answer answer) {
            em.merge(answer);
        }

        @Override
        public void deleteAnswer(long id) {
            try {
                em.remove(getAnswer(id));
            } catch (IllegalArgumentException ie) {
                return;
            }
        }

        @Override
        public Answer getAnswer(long id) {
            Answer answer = null;

            try {
                answer = em.find(Answer.class, id);
            } catch (NoResultException e) {}        

            return answer;
        }

        @SuppressWarnings("unchecked")
        @Override
        public List<Map<String, Object>> getAnswers(long quizId) {
            return (List<Map<String, Object>>) em.createQuery(ANSWER_SELECT_CLAUSE + " from Answer a where a.quizId = :quizId")
                    .setParameter("quizId", quizId)
                    .getResultList();
        }

        @SuppressWarnings("unchecked")
        @Override
        public List<Map<String, Object>> getQuizzes(int section) {
            return (List<Map<String, Object>>) em.createQuery(QUIZ_SELECT_CLAUSE + " from Quiz q where q.section = :section order by q.regDate desc")
                    .setParameter("section", section)
                    .getResultList();
        }

        @SuppressWarnings("unchecked")
        @Override
        public List<Map<String, Object>> getQuizzesDetails(int section) {
            return (List<Map<String, Object>>) em.createQuery("select q from Quiz q where q.section = :section order by q.regDate desc")
                    .setParameter("section", section)
                    .getResultList();
        }

        @Override
        public Answer getAnswerByQuizId(long quizId) {
            Answer answer = null;

            try {
                answer = em.find(Answer.class, quizId);
            } catch (NoResultException e) {

            }
            return answer;
        }

        @Override
        public void addQuizSubmission(QuizSubmission quizSubmission) {
            em.persist(quizSubmission);
        }

        @Override
        public void saveQuizSubmission(QuizSubmission quizSubmission) {
            em.merge(quizSubmission);
        }

        @Override
        public void deleteQuizSubmission(long id) {
            try {
                em.remove(getQuiz(id));
            } catch (IllegalArgumentException ie) {
                return;
            }
        }

        @Override
        public QuizSubmission getQuizSubmission(long id) {
            QuizSubmission quizSubmission = null;

            try {
                quizSubmission = em.find(QuizSubmission.class, id);
            } catch (NoResultException e) {}        

            return quizSubmission;
        }

        @SuppressWarnings("unchecked")
        @Override
        public List<Map<String, Object>> getQuizSubmissions(long quizId) {
            return (List<Map<String, Object>>) em.createQuery("select qs from QuizSubmission qs where qs.quizId = :quizId order by qs.date desc")
                    .setParameter("quizId", quizId)
                    .getResultList();
        }

        @SuppressWarnings("unchecked")
        @Override
        public List<QuizSubmission> getQuizSubmissions(String date) {
            /*return em.createNativeQuery("SELECT `id`, `quiz_id`, `answer_id`, `date` FROM `quizzes_submissions` WHERE DATE(`date`) = :date")
                    .setParameter("date", date )
                    .getResultList();*/

            SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            Date startDate = null;
            Date endDate = null;
            try {
                startDate = format.parse(date.trim()+" 00:00:00");
                endDate = format.parse(date.trim()+" 23:59:59");
            } catch (ParseException e) {
                e.printStackTrace();
            }

            return em.createQuery("select qs from QuizSubmission qs WHERE qs.date BETWEEN :startDate AND :endDate")
                    .setParameter("startDate", startDate)
                    .setParameter("endDate", endDate)
                    .getResultList();
        }
    }

我的 Controller 调用 QuizDaoImpl 的 getQuizzes(int section) 以便显示所有测验。

我的观察:完整的东西在新部署下运行良好，一旦数据库长期处于理想状态，6-8 小时后就会出现问题

root cause

org.hibernate.TransactionException: Already have an associated managed connection
    org.hibernate.engine.transaction.internal.jdbc.JdbcTransaction.doBegin(JdbcTransaction.java:65)
    org.hibernate.engine.transaction.spi.AbstractTransactionImpl.begin(AbstractTransactionImpl.java:160)
org.hibernate.internal.SessionImpl.beginTransaction(SessionImpl.java:1309)
org.hibernate.ejb.TransactionImpl.begin(TransactionImpl.java:57)
org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.enlistInCurrentTransaction(ExtendedEntityManagerCreator.java:421)
org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.doJoinTransaction(ExtendedEntityManagerCreator.java:398)
org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:356)
sun.proxy.$Proxy150.createQuery(Unknown Source)
com.next.persistence.QuizDaoImpl.getQuizzes(QuizDaoImpl.java:102)
sun.reflect.GeneratedMethodAccessor358.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:601)
org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318)
org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:155)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
sun.proxy.$Proxy163.getQuizzes(Unknown Source)
com.next.service.QuizServiceImpl.getQuizzes(QuizServiceImpl.java:92)
sun.reflect.GeneratedMethodAccessor357.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:601)
org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:318)
org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:183)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:110)
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
sun.proxy.$Proxy164.getQuizzes(Unknown Source)
com.next.mvc.HomeController.showListPage(HomeController.java:308)
sun.reflect.GeneratedMethodAccessor356.invoke(Unknown Source)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:601)
org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:213)
org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126)
org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617)
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578)
org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882)
org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:311)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:116)
org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:101)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:113)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:146)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:45)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.authentication.www.BasicAuthenticationFilter.doFilter(BasicAuthenticationFilter.java:150)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:182)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:173)
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)

最佳答案

问题出在@PersistenceContext 注释中。我有:

@PersistenceContext(type = PersistenceContextType.EXTENDED)
private EntityManager entityManager;

我用 :

代替了它

@PersistenceContext
private EntityManager entityManager;

关于java - 已经有关联的托管连接错误，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20756804/

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我什至不知道这是否可能，我非常怀疑它是否可能，但如果可以，您能告诉我怎么做吗？我只是想知道如何从打印机打印一些文本。有什么想法吗？最佳答案这里有更简单的事情。 import javax.swin

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java - 已经有关联的托管连接错误