通用 DAO 抛出 ClassCastException

Question

我有一个 GenericDAO 类，它由我所有类型特定的 DAO 扩展。这个通用的 DAO 类具有以下方法，并且工作正常。

protected List<T> findByCriteria(Criterion... criterion) {
    Criteria crit = getSession().createCriteria(getPersistentClass());
    for (Criterion c : criterion) {
        crit.add(c);
    }
    return crit.list();
}

现在，我所做的只是添加另一个具有更多参数的方法，但它会抛出异常“java.lang.ClassCastException：[Ljava.lang.String; 无法转换为 java.lang.String”。下面是方法签名。

 public List<T> getByCriteria(int iPage, int iCount, Order order, ProjectionList pl, Criterion... criteria){
    Criteria crit = getSession().createCriteria(getPersistentClass());
    for (Criterion c : criteria) {
         crit.add(c);
    }
    // set max results to return
    //crit.setMaxResults(iCount);
    // set first record in result starting from
    //crit.setFirstResult((iPage-1)*iCount);
    //crit.list();  // Doesn't matter even if I just put it one line above without assign
    return crit.list();   //This is the line which throws exception
}

我正在尝试向搜索功能添加更多过滤条件，但由于异常我注释掉了附加代码并且只是在模仿工作功能 findByCriteria。我在网上搜索，但无法弄清楚如何解决这个问题，或者第一种方法工作正常而第二种方法抛出错误。甚至两者生成的hibernate查询都是一样的。

更新： 下面是异常堆栈跟踪：

java.lang.ClassCastException: [Ljava.lang.String; cannot be cast to java.lang.String
at org.hibernate.type.descriptor.java.StringTypeDescriptor.unwrap(StringTypeDescriptor.java:39)
at org.hibernate.type.descriptor.sql.VarcharTypeDescriptor$1.doBind(VarcharTypeDescriptor.java:57)
at org.hibernate.type.descriptor.sql.BasicBinder.bind(BasicBinder.java:93)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:280)
at org.hibernate.type.AbstractStandardBasicType.nullSafeSet(AbstractStandardBasicType.java:275)
at org.hibernate.loader.Loader.bindPositionalParameters(Loader.java:1969)
at org.hibernate.loader.Loader.bindParameterValues(Loader.java:1940)
at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1875)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1836)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1816)
at org.hibernate.loader.Loader.doQuery(Loader.java:900)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:342)
at org.hibernate.loader.Loader.doList(Loader.java:2526)
at org.hibernate.loader.Loader.doList(Loader.java:2512)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2342)
at org.hibernate.loader.Loader.list(Loader.java:2337)
at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:124)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1662)
at org.hibernate.internal.CriteriaImpl.list(CriteriaImpl.java:374)
at com.felees.hbnpojogen.persistence.impl.GenericHibernateDaoImpl.getByCriteria(GenericHibernateDaoImpl.java:288)
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.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy44.getByCriteria(Unknown Source)
at com.wipro.wcc.services.data.DataLayerWccarchiveImpl.executeCriteria(DataLayerWccarchiveImpl.java:510)
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.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:98)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:262)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy37.executeCriteria(Unknown Source)
at com.wipro.wcc.controller.DocumentController.search(DocumentController.java:112)
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.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:214)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:748)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:945)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:931)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:833)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:807)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1008)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)

问候，

潘卡杰

Answer 1

我犯了一个愚蠢的错误。在准备标准数组时，传递了字符串数组而不是针对 like,lt,eq 等的值，这导致了问题。不知道我是怎么忽略的。