java - 重复注释错误 - 但在哪里？-6ren

java - 重复注释错误 - 但在哪里？

转载作者：塔克拉玛干更新时间：2023-11-03 04:48:28

简而言之，首先 - 我收到此异常消息:

serverError: class javax.faces.el.EvaluationException Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)

我的代码由 1 个表实体类、一个 EJB、一个“业务类”和一个 JSF 页面组成；当我调用 EntityManager.merge() 时发生异常。里面只有 1 个带有 'max = 128' 的注解:

@Size(max = 128)
@Column(name = "name")
private String name;

唯一有重复注释的地方是:

@Entity
@Table(name = "attributes", schema = "office_db")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Attributes.findAll", query = "SELECT a FROM Attributes a"),
    @NamedQuery(name = "Attributes.findById", query = "SELECT a FROM Attributes a WHERE a.id = :id"),
    @NamedQuery(name = "Attributes.findByName", query = "SELECT a FROM Attributes a WHERE a.name = :name"),
    @NamedQuery(name = "Attributes.findByType", query = "SELECT a FROM Attributes a where a.type.id = :type")
})

但我认为这应该是合法的，因为它是由 Netbeans 8.2 从数据库表生成的。

现在有更多细节。首先是表格:

mysql> show create table attributes\G
*************************** 1. row ***************************
       Table: attributes
Create Table: CREATE TABLE `attributes` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `parent` int(11) DEFAULT NULL,
  `type` int(11) DEFAULT NULL,
  `name` varchar(128) COLLATE utf8mb4_unicode_ci DEFAULT NULL,
  PRIMARY KEY (`id`),
  KEY `parent_ix` (`parent`),
  KEY `type_ix` (`type`),
  CONSTRAINT `attributes_parent_fk` FOREIGN KEY (`parent`) REFERENCES `attributes` (`id`),
  CONSTRAINT `attributes_type_fk` FOREIGN KEY (`type`) REFERENCES `attributes` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1301 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci
1 row in set (0.03 sec)

接下来是实体类:

import (...stuff...)

@Entity
@Table(name = "attributes")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "Attributes.findAll", query = "SELECT a FROM     Attributes a"),
    @NamedQuery(name = "Attributes.findById", query = "SELECT a FROM Attributes a WHERE a.id = :id"),
    @NamedQuery(name = "Attributes.findByName", query = "SELECT a FROM Attributes a WHERE a.name = :name"),
    @NamedQuery(name = "Attributes.findByType", query = "SELECT a FROM Attributes a where a.type.id = :type")
})
public class Attributes implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Integer id;
    @Size(max = 128)
    @Column(name = "name")
    private String name;
    @OneToMany(mappedBy = "parent")
    private Collection<Attributes> attributesCollection;
    @JoinColumn(name = "parent", referencedColumnName = "id")
    @ManyToOne
    private Attributes parent;
    @OneToMany(mappedBy = "type")
    private Collection<Attributes> attributesCollection1;
    @JoinColumn(name = "type", referencedColumnName = "id")
    @ManyToOne
    private Attributes type;
    private static final Logger logger=
            Logger.getLogger(Attributes.class.getName());

    public Attributes() {
    }

    public Attributes(Integer id) {
        this.id = id;
    }
    public Attributes(Integer id, Integer parent, Integer type, String name) {
        logger.info("OFFICE Attributes constructor 3 id: "+id+", parent:     "+parent+", type: "+type+", name: "+name);
        this.parent=new Attributes();
        this.type=new Attributes();
        this.id = id;
        this.parent.setId(parent);
        this.type.setId(type);
        this.name = name;
    }

    public Attributes(Integer parent, Integer type, String name) {
        logger.info("OFFICE Attributes constructor 4 parent: "+parent+", type: "+type+", name: "+name);
        this.parent=new Attributes();
        this.type=new Attributes();
        this.parent.setId(parent);
        this.type.setId(type);
        this.name = name;
        logger.info("OFFICE Attributes constructor 4a");
    }

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    @XmlTransient
    public Collection<Attributes> getAttributesCollection() {
        return attributesCollection;
    }

    public void setAttributesCollection(Collection<Attributes> attributesCollection) {
        this.attributesCollection = attributesCollection;
    }

    public Attributes getParent() {
        return parent;
    }

    public void setParent(Attributes parent) {
        this.parent = parent;
    }

    @XmlTransient
    public Collection<Attributes> getAttributesCollection1() {
        return attributesCollection1;
    }

    public void setAttributesCollection1(Collection<Attributes> attributesCollection1) {
        this.attributesCollection1 = attributesCollection1;
    }

    public Attributes getType() {
        return type;
    }

    public void setType(Attributes type) {
        this.type = type;
    }

    @Override
    public int hashCode() {
        int hash = 0;
        hash += (id != null ? id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object object) {
        // TODO: Warning - this method won't work in the case the id fields are not set
        if (!(object instanceof Attributes)) {
            return false;
        }
        Attributes other = (Attributes) object;
        if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return "docdb.Attributes[ id=" + id + " ]";
    }
}

EJB 或 session 类:

import (...stuff...)

@Stateless
public class AttributesSession {
    @PersistenceContext(unitName ="officePU")
    private EntityManager em;
    private static final Logger logger=
            Logger.getLogger(AttributesSession.class.getName());

    public List<Attributes>findAttributes(){
        TypedQuery<Attributes> query=
                    em.createNamedQuery("Attributes.findAll",Attributes.class);
        return query.getResultList();
    }

    public Attributes findAttributeById(Long id){
        TypedQuery<Attributes> query=
                em.createNamedQuery("Attributes.findById", Attributes.class);
        query.setParameter("id", id);
        return query.getSingleResult();
    }

    public Integer findChildCount(Long id){
        TypedQuery<Integer> query=em.createNamedQuery("findChildCount",Integer.class);
        query.setParameter("id", id);
        return query.getSingleResult();
    }

    public String createAttributes(Attributes attr){
        String msg="";

        try{
            em.merge(attr);
            em.flush();
        }
        catch (PersistenceException e){
            msg=e.getMessage();
        }
        return msg;
    }

    public String deleteAttributes(Attributes attr){
        String msg = "";

        try{
            em.remove(em.merge(attr));
            em.flush();
        }
        catch (PersistenceException e){
            msg=e.getMessage();
        }
        return msg;
    }
}

业务或 Controller 类:

import (...stuff...)

@Named(value = "attributesController")
@SessionScoped
public class AttributesController implements Serializable{
    @EJB private AttributesSession sess;
    private Attributes attr;
    private List<Attributes> attrList;
    private Integer id;
    private Integer parent;
    private Integer type;
    private String name;
    private String errmsg;
    private static final Logger logger=
            Logger.getLogger(AttributesController.class.getName());

    public AttributesController() {
        this.attrList = new ArrayList<>();
        this.attr = new Attributes();
    }

    public List<Attributes> getAttrList() {
        return attrList;
    }

    public List<Attributes> getAttrValueList() {
        return attrList;
    }

    ...getters and setters...

    public void clearForm(){
        this.id=null;
        this.name=null;
        this.parent=null;
        this.type=null;
        this.errmsg=null;
    }

    public String createAttributes(){
        if (this.id!=null){
            attr=new Attributes(this.id,this.parent,this.type,this.name);
        }
        else{
            attr=new Attributes(this.parent,this.type,this.name);
        }
        errmsg=sess.createAttributes(attr);
        attrList=sess.findAttributes();
        return "editattributes.xhtml";
    }

    public String deleteAttributes(){
        if (this.id!=null){
            attr=new Attributes(this.id,this.parent,this.type,this.name);
            errmsg=sess.deleteAttributes(attr);
        }
        attrList=sess.findAttributes();
        return "editattributes.xhtml";
    }

    public String listAttributes(){
        attrList=sess.findAttributes();
        return "editattributes.xhtml";
    }

    @PostConstruct
    public void updateList(){
        attrList=sess.findAttributes();
    }

    @Override
    public String toString(){
        return "Name: "+((name==null)?"":name)
                +", parent: "+((parent==null)?"":parent)
                +", type:"+((type==null)?"":type);
    }
}

最后，堆栈跟踪:

[2017-10-31T10:23:31.697+0000] [glassfish 5.0] [WARNING] [] [javax.enterprise.resource.webcontainer.jsf.lifecycle] [tid: _ThreadID=27 _ThreadName=http-listener-1(1)] [timeMillis: 1509445411697] [levelValue: 900] [[
  #{attributesController.createAttributes()}: java.lang.annotation.AnnotationFormatError: Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)
javax.faces.FacesException: #{attributesController.createAttributes()}: java.lang.annotation.AnnotationFormatError: Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)
        ...(deleted stuff)
        ... 35 more
Caused by: java.lang.annotation.AnnotationFormatError: Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)
        ... (stuff deleted)
        at docdb.__EJB31_Generated__AttributesSession__Intf____Bean__.createAttributes(Unknown Source)
        at docdb.AttributesController.createAttributes(AttributesController.java:118)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:483)
        at javax.el.ELUtil.invokeMethod(ELUtil.java:304)
        at javax.el.BeanELResolver.invoke(BeanELResolver.java:535)
        at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:256)
        at com.sun.el.parser.AstValue.invoke(AstValue.java:285)
        at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:304)
        at org.jboss.weld.module.web.util.el.ForwardingMethodExpression.invoke(ForwardingMethodExpression.java:40)
        at org.jboss.weld.module.web.el.WeldMethodExpression.invoke(WeldMethodExpression.java:50)
        at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:107)
        at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:87)
        ... 36 more
]]

[2017-10-31T10:23:31.700+0000] [glassfish 5.0] [INFO] [] [docdb.LifeCycleListener] [tid: _ThreadID=27 _ThreadName=http-listener-1(1)] [timeMillis: 1509445411700] [levelValue: 800] [[
  OFFICE END PHASE INVOKE_APPLICATION 5]]

[2017-10-31T10:23:31.701+0000] [glassfish 5.0] [INFO] [] [docdb.LifeCycleListener] [tid: _ThreadID=27 _ThreadName=http-listener-1(1)] [timeMillis: 1509445411701] [levelValue: 800] [[
  OFFICE]]

[2017-10-31T10:23:31.703+0000] [glassfish 5.0] [SEVERE] [] [javax.enterprise.resource.webcontainer.jsf.context] [tid: _ThreadID=27 _ThreadName=http-listener-1(1)] [timeMillis: 1509445411703] [levelValue: 1000] [[
  javax.faces.el.EvaluationException: java.lang.annotation.AnnotationFormatError: Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)
        at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:101)
        at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102)
        at javax.faces.component.UICommand.broadcast(UICommand.java:330)
        at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:870)
        at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1418)
        at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:82)
        at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:100)
        at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:201)
        at javax.faces.webapp.FacesServlet.service(FacesServlet.java:670)
        at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1580)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:258)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160)
        at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:652)
        at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:591)
        at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155)
        at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:371)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:238)
        at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:463)
        at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:168)
        at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:206)
        at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:180)
        at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:242)
        at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
        at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284)
        at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201)
        at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133)
        at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112)
        at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
        at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:539)
        at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112)
        at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
        at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
        at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
        at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:593)
        at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:573)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.annotation.AnnotationFormatError: Duplicate annotation for class: interface javax.validation.constraints.Size: @javax.validation.constraints.Size(groups=[], min=0, message={javax.validation.constraints.Size.message}, payload=[], max=128)
        at sun.reflect.annotation.TypeAnnotationParser.mapTypeAnnotations(TypeAnnotationParser.java:361)
        at sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl.<init>(AnnotatedTypeFactory.java:139)
        at sun.reflect.annotation.AnnotatedTypeFactory.buildAnnotatedType(AnnotatedTypeFactory.java:65)
        at sun.reflect.annotation.TypeAnnotationParser.buildAnnotatedType(TypeAnnotationParser.java:79)
        at java.lang.reflect.Field.getAnnotatedType(Field.java:1159)
        at org.hibernate.validator.internal.metadata.provider.AnnotationMetaDataProvider.findCascadingMetaData(AnnotationMetaDataProvider.java:610)
        at org.hibernate.validator.internal.metadata.provider.AnnotationMetaDataProvider.findPropertyMetaData(AnnotationMetaDataProvider.java:231)
        at org.hibernate.validator.internal.metadata.provider.AnnotationMetaDataProvider.getFieldMetaData(AnnotationMetaDataProvider.java:220)
        at org.hibernate.validator.internal.metadata.provider.AnnotationMetaDataProvider.retrieveBeanConfiguration(AnnotationMetaDataProvider.java:128)
        at org.hibernate.validator.internal.metadata.provider.AnnotationMetaDataProvider.getBeanConfiguration(AnnotationMetaDataProvider.java:119)
        at org.hibernate.validator.internal.metadata.BeanMetaDataManager.getBeanConfigurationForHierarchy(BeanMetaDataManager.java:220)
        at org.hibernate.validator.internal.metadata.BeanMetaDataManager.createBeanMetaData(BeanMetaDataManager.java:187)
        at org.hibernate.validator.internal.metadata.BeanMetaDataManager.lambda$getBeanMetaData$0(BeanMetaDataManager.java:160)
        at org.hibernate.validator.internal.metadata.BeanMetaDataManager$$Lambda$24/1020030882.apply(Unknown Source)
        at java.util.concurrent.ConcurrentMap.computeIfAbsent(ConcurrentMap.java:324)
        at org.hibernate.validator.internal.metadata.BeanMetaDataManager.getBeanMetaData(BeanMetaDataManager.java:159)
        at org.hibernate.validator.internal.engine.ValidatorImpl.getConstraintsForClass(ValidatorImpl.java:308)
        at org.eclipse.persistence.internal.jpa.metadata.listeners.BeanValidationListener.isBeanConstrained(BeanValidationListener.java:158)
        at org.eclipse.persistence.internal.jpa.metadata.listeners.BeanValidationListener.validateOnCallbackEvent(BeanValidationListener.java:108)
        at org.eclipse.persistence.internal.jpa.metadata.listeners.BeanValidationListener.preUpdate(BeanValidationListener.java:94)
        at org.eclipse.persistence.descriptors.DescriptorEventManager.notifyListener(DescriptorEventManager.java:726)
        at org.eclipse.persistence.descriptors.DescriptorEventManager.notifyEJB30Listeners(DescriptorEventManager.java:696)
        at org.eclipse.persistence.descriptors.DescriptorEventManager.executeEvent(DescriptorEventManager.java:233)
        at org.eclipse.persistence.descriptors.changetracking.DeferredChangeDetectionPolicy.calculateChanges(DeferredChangeDetectionPolicy.java:87)
        at org.eclipse.persistence.descriptors.changetracking.AttributeChangeTrackingPolicy.calculateChangesForExistingObject(AttributeChangeTrackingPolicy.java:48)
        at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.calculateChanges(UnitOfWorkImpl.java:711)
        at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.commitToDatabaseWithChangeSet(UnitOfWorkImpl.java:1566)
        at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.issueSQLbeforeCompletion(UnitOfWorkImpl.java:3256)
        at org.eclipse.persistence.internal.sessions.RepeatableWriteUnitOfWork.issueSQLbeforeCompletion(RepeatableWriteUnitOfWork.java:355)
        at org.eclipse.persistence.transaction.AbstractSynchronizationListener.beforeCompletion(AbstractSynchronizationListener.java:158)
        at org.eclipse.persistence.transaction.JTASynchronizationListener.beforeCompletion(JTASynchronizationListener.java:68)
        at com.sun.enterprise.transaction.JavaEETransactionImpl.commit(JavaEETransactionImpl.java:452)
        at com.sun.enterprise.transaction.JavaEETransactionManagerSimplified.commit(JavaEETransactionManagerSimplified.java:854)
        at com.sun.ejb.containers.EJBContainerTransactionManager.completeNewTx(EJBContainerTransactionManager.java:723)
        at com.sun.ejb.containers.EJBContainerTransactionManager.postInvokeTx(EJBContainerTransactionManager.java:507)
        at com.sun.ejb.containers.BaseContainer.postInvokeTx(BaseContainer.java:4600)
        at com.sun.ejb.containers.BaseContainer.postInvoke(BaseContainer.java:2108)
        at com.sun.ejb.containers.BaseContainer.postInvoke(BaseContainer.java:2078)
        at com.sun.ejb.containers.EJBLocalObjectInvocationHandler.invoke(EJBLocalObjectInvocationHandler.java:220)
        at com.sun.ejb.containers.EJBLocalObjectInvocationHandlerDelegate.invoke(EJBLocalObjectInvocationHandlerDelegate.java:88)
        at com.sun.proxy.$Proxy175.createAttributes(Unknown Source)
        at docdb.__EJB31_Generated__AttributesSession__Intf____Bean__.createAttributes(Unknown Source)
        at docdb.AttributesController.createAttributes(AttributesController.java:118)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:483)
        at javax.el.ELUtil.invokeMethod(ELUtil.java:304)
        at javax.el.BeanELResolver.invoke(BeanELResolver.java:535)
        at javax.el.CompositeELResolver.invoke(CompositeELResolver.java:256)
        at com.sun.el.parser.AstValue.invoke(AstValue.java:285)
        at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:304)
        at org.jboss.weld.module.web.util.el.ForwardingMethodExpression.invoke(ForwardingMethodExpression.java:40)
        at org.jboss.weld.module.web.el.WeldMethodExpression.invoke(WeldMethodExpression.java:50)
        at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:107)
        at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:87)
        ... 36 more
]]

最佳答案

如果 @NamedQueries 是个问题，我会非常惊讶，顾名思义它应该是 @NamedQuery 项的列表/数组。

尝试:

@Column(name = "name", length = 128)
private String name;

既然你确信你实际上没有重复 @size，也许我们应该看看函数的重叠，@Column 注释包含相同的功能，这可能会导致冲突。

关于java - 重复注释错误 - 但在哪里？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/47019186/

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