java - JPA 标准 : Convert int to String then select from substring of resulting String

Question

我有一个 String 作为参数(实际上是一个 valueOf(an Integer)，并且想将它与数据库中 int 值的子字符串进行比较。这是我的代码:

ClinicPatients clp = null;

// Get the criteria builder instance from entity manager
final CriteriaBuilder cb = getEntityManager().getCriteriaBuilder();     
// Create criteria query and pass the value object which needs to be populated as result
CriteriaQuery<ClinicPatients> criteriaQuery = cb.createQuery(ClinicPatients.class);     
// Tell to criteria query which tables/entities you want to fetch
final Root<ClinicPatients> rootClp = criteriaQuery.from(ClinicPatients.class);

criteriaQuery.select(rootClp);

Expression<String> e1 = cb.function("CONVERT", String.class, rootClp.get(idCPFieldName));

Predicate p1 = cb.equal(cb.substring(e1, 1, 3), idClinicPatient);
criteriaList.add(p1);

criteriaQuery.where(p1);

// Here entity manager will create actual SQL query out of criteria query
final TypedQuery<ClinicPatients> query = getEntityManager().createQuery(criteriaQuery);

List<ClinicPatients> lClps = (List<ClinicPatients>) query.getResultList();
if(lClps.size() > 0)
    clp = lClps.get(0);

return clp;

我得到一个错误，我的猜测是从未完成到 String 的转换，然后 Hibernate 尝试对一些奇怪的值进行子字符串化，但此时我不确定任何事情。这是我得到的痕迹:

> DEBUG could not extract ResultSet [n/a] com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an
> error in your SQL syntax; check the manual that corresponds to your
> MySQL server version for the right syntax to use near '), 1, 3)='005''
> at line 1     at
> sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
>   at
> sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
>   at
> sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
>   at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
>   at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)     at
> com.mysql.jdbc.Util.getInstance(Util.java:386)    at
> com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)    at
> com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4190)    at
> com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4122)    at
> com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)     at
> com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)  at
> com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2818)   at
> com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2157)
>   at
> com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2324)
>   at
> org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:80)
>   at org.hibernate.loader.Loader.getResultSet(Loader.java:2065)   at
> org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1862)
>   at
> org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1838)
>   at org.hibernate.loader.Loader.doQuery(Loader.java:909)     at
> org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:354)
>   at org.hibernate.loader.Loader.doList(Loader.java:2553)     at
> org.hibernate.loader.Loader.doList(Loader.java:2539)  at
> org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2369)    at
> org.hibernate.loader.Loader.list(Loader.java:2364)    at
> org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:496)   at
> org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:387)
>   at
> org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:231)
>   at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1264)   at
> org.hibernate.internal.QueryImpl.list(QueryImpl.java:103)     at
> org.hibernate.jpa.internal.QueryImpl.list(QueryImpl.java:573)     at
> org.hibernate.jpa.internal.QueryImpl.getResultList(QueryImpl.java:449)
>   at
> org.hibernate.jpa.criteria.compile.CriteriaQueryTypeQueryAdapter.getResultList(CriteriaQueryTypeQueryAdapter.java:67)
>   at
> ca.chronometriq.commons.cmqfacade.ClinicPatientsFacade.findByIDClinicPatientFirstThreeDigitsVerificationNumber(ClinicPatientsFacade.java:150)
>   at
> ca.chronometriq.commons.cmqfacade.ClinicPatientsFacade$$FastClassByCGLIB$$7cc86440.invoke(<generated>)
>   at
> org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
>   at
> org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:698)
>   at
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
>   at
> org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
>   at
> org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
>   at
> org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
>   at
> org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
>   at
> org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:631)
>   at
> ca.chronometriq.commons.cmqfacade.ClinicPatientsFacade$$EnhancerByCGLIB$$8afa98d9.findByIDClinicPatientFirstThreeDigitsVerificationNumber(<generated>)    at
> ca.chronometriq.webterm.restapi.AdminModule.findByThreeDig(AdminModule.java:1474)
>   at
> ca.chronometriq.webterm.restapi.AdminModule$$FastClassByCGLIB$$2e650668.invoke(<generated>)
>   at
> org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
>   at
> org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:627)
>   at
> ca.chronometriq.webterm.restapi.AdminModule$$EnhancerByCGLIB$$e2195e01.findByThreeDig(<generated>)
>   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
> com.sun.jersey.spi.container.JavaMethodInvokerFactory$1.invoke(JavaMethodInvokerFactory.java:60)
>   at
> com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$TypeOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:185)
>   at
> com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:75)
>   at
> com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:288)
>   at
> com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
>   at
> com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:108)
>   at
> com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:147)
>   at
> com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:84)
>   at
> com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1469)
>   at
> com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1400)
>   at
> com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349)
>   at
> com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339)
>   at
> com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416)
>   at
> com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537)
>   at
> com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699)
>   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.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
>   at
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
>   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:611)
>   at
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
>   at
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
>   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:409)
>   at
> org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1044)
>   at
> org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:607)
>   at
> org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1721)
>   at
> org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1679)
>   at
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
>   at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
>   at java.lang.Thread.run(Thread.java:744)

有什么想法吗？

Answer 1

您是否尝试过使用 as :

Expression<String> e1 = rootClp.get(idCPFieldName).as(String.class);

曾经有一个bug在此功能中，因此如果您使用的是旧版本，您可能会遇到这种情况。