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Strings in JPQL and Criteria Queries

Explains string expressions in JPQL queries, including LIKE, LOCATE, LOWER, UPPER, TRIM, CONCAT and SUBSTRING.... SUBSTRING - Getting a Portion of a String Java String Methods (ObjectDB Extension) Criteria Query String ... are one-based (as in SQL) rather then zero-based (as in Java). Therefore, the position of the first character is 1 . Zero ( 0 ) is ...

 
tutorial

Eclipse/JPA Web Application Tutorial

Step by step tutorial that demonstrates how to build a simple database web application (with Servlet and JSP) in Eclipse using JPA.... create and run a database driven Java web application in Eclipse - using Tomcat 6, ObjectDB and JPA. The ... you will need the following software: Java JDK 6.0 (or above). Eclipse IDE for Java EE Developers Apache Tomcat Server 6.0  ( some ...

 
forum_thread

find repeated records by JPQL

Hi, I know a single command in MySQL can find repeated records: Select * from TTT t where id in (select id from TTT s group id having count(id)>1) I dont know how to do this using JPQL, but I use query from 430,000 records and put them into hashmap, finally it cost one hour and failed: ... . jpa . JpaQuery . getResultList ( JpaQuery. java : 636 ) at image. cleanDB . main ( cleanDB. java : 19 ) Caused by : com. objectdb . o . ...

 
forum_thread

JBoss 7 startup fails

Hi, I was having a go with entity beans 3.x jboss 7, objectdb and the guestbook web application but cannot come out of the swamp. I use eclipse indigo as IDE The "src" folder contains the pachake guest and within the classes: Guest.java, GuestListener.java and GuestServlet.java The WebContent/META-INF dir contains: context.xml ... contains the pachake guest and within the classes: Guest.java, GuestListener.java and GuestServlet.java The WebContent/META-INF dir contains: ...

 
issue

com.objectdb.o.InternalException: java.lang.ArrayIndexOutOfBoundsException: null:

The following error appears under and extended persistence context, and with creation, configuration and wiring code that is known to work perfectly with EclipseLink+Glassfish: SEVERE: Unexpected internal exception ... exception ( Error 990 ) Generated by Java HotSpot ( TM ) 64 - Bit Server VM 1.6.0_26 ( on ... com. objectdb . o . InternalException : java. lang . ArrayIndexOutOfBoundsException : null java. lang . ...

 
forum_thread

Threading Problem (maybe with Criteria)

Hi all I found some threading problems I do not understand: here is the the link to the testcase http://www.advolux.de/weblink%20forum/test.zip ... UIDs in 32 msek Exception in thread "Thread-2" java. util . ConcurrentModificationException at java. util . LinkedHashMap $LinkedHashIterator. nextEntry ( LinkedHashMap. java : 394 ) at java. util . LinkedHashMap $EntryIterator. ...

 
forum_thread

ClassCastException on SELECT NEW ... after UPDATE over Java RMI

Hi, we are using ObjectDB 2.5.4_04 on Linux. Our application, which uses ObjectDb as a DB, exposes a Java RMI interface which allows remote RMI clients to run JPQL queries on the DB. The application internally runs SELECT NEW ... queries. For example: ... Our application, which uses ObjectDb as a DB, exposes a Java RMI interface which allows remote RMI clients to run JPQL queries on the ... r.fileName)' (error 783) at java.awt.AWTEventMulticaster.mouseMoved(AWTEventMulticaster.java:330) ...

 
issue

ObjectDB-2.6.9: Failed to commit transaction: Failed to set numeric value of field property Element.id using reflection

The following error is reported for objectdb-2.6.9.jar: Failed to commit transaction: Failed to set numeric value of field property com.greensoft.objectdb.test.entity.Element.id using reflection (error 613) Did not happen with objectdb-2.6.3_04 (which one can easily test and compare in the test console app for NetBeans8.1 provided, as explained below). To reproduce download the app and unpack, open in NetBeans8.1, perform Clean and Build, and Run: ... classes. When you clean and build it will report: Java/JVM version: 1.8 Java/JVM detail version: 1.8.0_74 ObjectDB enhancer: begin: (all classes within ...

 
forum_thread

Guessbook tutorial: Java EE 6 JPA Tutorial - Maven Project

I have a Max OSX Lion and am running Netbeans 7.2 with Glassfish 3.1.2. I download the tutorial and run it. The moment I type something in the sign in block and click add, I get the following error trace: (Does anyone know a fix?)   ... ... ... ... ... ... ... $Proxy196.persist(Unknown Source) at ... Source) at guest.GuestServlet.doPost(GuestServlet.java:36) at javax.servlet.http.HttpServlet.service(HttpServlet.java:688) at javax.servlet.http.HttpServlet.service(HttpServlet.java:770) at ...

 
forum_thread

Objectdb server out of heap space

I have had a server crash with the following stack trace: ... had a server crash with the following stack trace: java. lang . OutOfMemoryError : Java heap space at java. nio . HeapByteBuffer .<init> ( ...