Call getNextException to see the cause : How to make Hibernate / JPA show the DB server message for an exception

This worked for me to get the exception message which caused the problem (Hibernate 3.2.5.ga):

catch (JDBCException jdbce) {    jdbce.getSQLException().getNextException().printStackTrace();}

There is no need to write any custom code to achieve this - Hibernate will log the exception cause by default. If you can't see this, Hibernate logging must not be set up correctly. Here's an example with slf4j+log4j, and using Maven for dependency management.

src/main/java/pgextest/PGExceptionTest.java

public class PGExceptionTest {    public static void main(String[] args) throws Exception {        EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory(                "pgextest");        EntityManager entityManager = entityManagerFactory.createEntityManager();        entityManager.getTransaction().begin();        // here I attempt to persist an object with an ID that is already in use        entityManager.persist(new PGExceptionTestBean(1));        entityManager.getTransaction().commit();        entityManager.close();    }}

src/main/resources/log4j.properties

log4j.rootLogger=ERROR, stdoutlog4j.appender.stdout=org.apache.log4j.ConsoleAppenderlog4j.appender.stdout.layout=org.apache.log4j.PatternLayoutlog4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

src/main/resources/META-INF/persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"        xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"        version="2.0">    <persistence-unit name="pgextest">        <properties>            <property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver"/>            <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost/pgextest"/>            <property name="javax.persistence.jdbc.user" value="postgres"/>            <property name="javax.persistence.jdbc.password" value="postgres"/>            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect"/>            <property name="hibernate.jdbc.batch_size" value="5"/>        </properties>    </persistence-unit></persistence>

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">    <modelVersion>4.0.0</modelVersion>    <groupId>pgextest</groupId>    <artifactId>pgextest</artifactId>    <version>0.0.1-SNAPSHOT</version>    <build>        <plugins>            <plugin>                <artifactId>maven-compiler-plugin</artifactId>                <configuration>                    <source>1.6</source>                    <target>1.6</target>                </configuration>            </plugin>        </plugins>    </build>    <dependencies>        <dependency>            <groupId>org.hibernate</groupId>            <artifactId>hibernate-entitymanager</artifactId>            <version>3.6.9.Final</version>        </dependency>           <dependency>            <groupId>postgresql</groupId>            <artifactId>postgresql</artifactId>            <version>9.1-901.jdbc4</version>            <scope>runtime</scope>        </dependency>        <dependency>            <groupId>org.slf4j</groupId>            <artifactId>slf4j-log4j12</artifactId>            <version>1.6.1</version>            <scope>runtime</scope>        </dependency>        <dependency>            <groupId>log4j</groupId>            <artifactId>log4j</artifactId>            <version>1.2.15</version>            <scope>runtime</scope>        </dependency>    </dependencies></project>

Executing the main method will then log the following:

ERROR [main] - Batch entry 0 insert into PGExceptionTestBean (label, id) values (NULL, '1') was aborted.  Call getNextException to see the cause.ERROR [main] - ERROR: duplicate key value violates unique constraint "pgexceptiontestbean_pkey"

It's probably worth mentioning that you can disable the JDBC batching that wraps the original exception by setting the property hibernate.jdbc.batch_size to 0 (needless to say you probably don't want to do this in production.)

I think Aspect Programming is a better solution to solve this kind of problem.

But, if you want to write a custom code to do that, you can catch SqlException and loop through it and log each exception. Something like this should work.

try { // whatever your code is} catch (SQLException e) {    while(e!= null) {      logger.log(e);      e = e.getNextException();    }}