本機查詢的休眠異常

Question

我有一個Hiberante本機查詢獲取大量的數據。到現在爲止，它的工作沒有打嗝，但由於某些原因，我得到了下面給出的例外情況。我應該如何試圖找出原因呢？

我的本地查詢格式爲：

Query query = entityManager.createNativeQuery(sql); 
    query.setParameter(1, foo); 
    List<Object[]> results = query.getResultList(); 

的實際查詢由兩個內部聯接，左多外連接，WHERE條件和秩序由三列的。它沒有任何對sql函數的調用。它確實使用索引，因爲它是一個很大的查詢。這個問題發生在Hibernate 4 beta 5和4.1.1上，使用MySQL 5.5

還有其他的查詢，但是異常直接關係到爲該本機查詢調用query.getResultList時。難道是休眠迫使一些其他的查詢執行隨後也（因爲懶惰或別的東西嗎？）

Caused by: java.lang.NullPointerException 
    at org.hibernate.engine.jdbc.internal.proxy.ResultSetProxyHandler.getJdbcServices(ResultSetProxyHandler.java:57) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.engine.jdbc.internal.proxy.AbstractResultSetProxyHandler.continueInvocation(AbstractResultSetProxyHandler.java:110) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:80) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at $Proxy305.wasNull(Unknown Source) at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:66) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:269) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:265) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:243) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.custom.CustomLoader$ScalarResultColumnProcessor.extract(CustomLoader.java:549) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.custom.CustomLoader$ResultRowProcessor.buildResultRow(CustomLoader.java:499) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.custom.CustomLoader$ResultRowProcessor.buildResultRow(CustomLoader.java:478) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.custom.CustomLoader.getResultColumnOrRow(CustomLoader.java:375) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:668) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.doQuery(Loader.java:860) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:289) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.doList(Loader.java:2449) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.doList(Loader.java:2435) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2276) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.Loader.list(Loader.java:2271) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:331) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.internal.SessionImpl.listCustomQuery(SessionImpl.java:1571) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.internal.AbstractSessionImpl.list(AbstractSessionImpl.java:224) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.internal.SQLQueryImpl.list(SQLQueryImpl.java:156) [hibernate-core-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:252) [hibernate-entitymanager-4.0.0.Beta5.jar:4.0.0.Beta5] 
    at com.foo.bar.getResults(MyResultHandler.java:114) [classes:] 
    at sun.reflect.GeneratedMethodAccessor16978.invoke(Unknown Source) [:1.7.0] 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [:1.7.0] 
    at java.lang.reflect.Method.invoke(Method.java:601) [:1.7.0] 
    at org.jboss.as.ee.component.ManagedReferenceMethodInterceptor.processInvocation(ManagedReferenceMethodInterceptor.java:51) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.InterceptorContext$Invocation.proceed(InterceptorContext.java:370) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.weld.ejb.Jsr299BindingsInterceptor.doMethodInterception(Jsr299BindingsInterceptor.java:114) [jboss-as-weld-7.0.1.Final.jar:7.0.1.Final] 
    at org.jboss.as.weld.ejb.Jsr299BindingsInterceptor.processInvocation(Jsr299BindingsInterceptor.java:122) [jboss-as-weld-7.0.1.Final.jar:7.0.1.Final] 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.WeavedInterceptor.processInvocation(WeavedInterceptor.java:53) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.jpa.interceptor.SBInvocationInterceptor.processInvocation(SBInvocationInterceptor.java:45) [jboss-as-jpa-7.0.1.Final.jar:7.0.1.Final] 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ejb3.component.stateful.StatefulSessionSynchronizationInterceptor.processInvocation(StatefulSessionSynchronizationInterceptor.java:132) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ee.component.NamespaceContextInterceptor.processInvocation(NamespaceContextInterceptor.java:44) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ee.component.TCCLInterceptor.processInvocation(TCCLInterceptor.java:45) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.InitialInterceptor.processInvocation(InitialInterceptor.java:21) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.invocation.ChainedInterceptor.processInvocation(ChainedInterceptor.java:61) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ee.component.ViewDescription$ComponentDispatcherInterceptor.processInvocation(ViewDescription.java:202) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.jpa.interceptor.SFSBInvocationInterceptor.processInvocation(SFSBInvocationInterceptor.java:58) [jboss-as-jpa-7.0.1.Final.jar:7.0.1.Final] 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ejb3.component.stateful.StatefulComponentInstanceInterceptor.processInvocation(StatefulComponentInstanceInterceptor.java:61) 
    at org.jboss.invocation.InterceptorContext.proceed(InterceptorContext.java:287) [jboss-invocation-1.1.0.Final.jar:1.1.0.Final] 
    at org.jboss.as.ejb3.component.session.SessionInvocationContextInterceptor$CustomSessionInvocationContext.proceed(SessionInvocationContextInterceptor.java:126) 
    at org.jboss.ejb3.tx2.impl.CMTTxInterceptor.invokeInCallerTx(CMTTxInterceptor.java:233) 
    ... 93 more 

Answer 1

你可以從一個空的列期待一個原始的。

Hibernate使用反射來創建對象。

public class A { 
    private long id; 

    private int n; 

    public void setN(int n) { this.n = n; } 
    public int getN() { return this.n; } 

    // id 
} 

如果您檢索A對象與DAO.get(id, A.class)將安裝這樣的：

select a_.id, a_.n from A a_ where a_id = ? /* Where ? is the id */ 

然後，它會做這樣（請注意，這只是爲了說明我的例子）：

A a = new A(); 

a.setId([a_.id]) 
a.setN([a_.n]) 

如果您檢索兩行：

id  n 
1  1 
2  NULL 

它會嘗試實例化一個A對象並將其n屬性設置爲setN(null)。由於簽名是一個原語，因此會引發錯誤。

查看錶格說明以查看是否存在任何可以爲空的列。如果是這樣，請不要期望setter中有任何基元。

這意味着當hibernate執行setPrimitive(null) // signature setPrimitive(long l)失敗。