Problem configuring Hibernate and JPA in Eclipse

[James Dekker]

I am having difficulty running sample code from Hibernate Made Easy by Cameron McKenzie.

Tools / Libraries:

(1) Eclipse 3.5

(2) MySQL 5

(3) Hibernate 3.3.2.GA

(4) Hibernate Annotations 3.4.0.GA

Wrote a simple User class (located under /examscam/src):

package com.examscam.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

import org.hibernate.cfg.AnnotationConfiguration;

@Entity
public class User {

	private long id;
	private String password;

	@Id
	@GeneratedValue
	public long getId() {
		return id;
	}

	public void setId(long id) {
		this.id = id;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}
}

Wrote a TestApp (containing main() method - located under /examscam/src):

package com.examscam.app;

import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;

import com.examscam.model.User;

public class TestApp {

	public static void main(String[] args) {
		AnnotationConfiguration config = new AnnotationConfiguration();
		config.addAnnotatedClass(User.class);
		config.configure();
		new SchemaExport(config).create(true, true);
	}
}

hibernate.cfg.xml (located under /examscam/src):

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>

        <!-- Database connection settings -->
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
		<property name="connection.url">jdbc:mysql://localhost/examscam</property>
        <property name="connection.username">root</property>
        <property name="connection.password"></property>

        <!-- JDBC connection pool (use the built-in) -->
        <property name="connection.pool_size">2</property>

        <!-- SQL dialect -->
		<property name="dialect">org.hibernate.dialect.MySQLDialect</property>

		<property name="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>

        <!-- Enable Hibernate's current session context -->
        <property name="current_session_context_class">org.hibernate.context.ManagedSessionContext</property>

        <!-- Disable the second-level cache  -->
        <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>

        <!-- Echo all executed SQL to stdout -->
        <property name="show_sql">true</property>

   </session-factory>
</hibernate-configuration>

Eclipse Build Path:

ant-contrib-1.0b2.jar, ant-junit-1.6.5.jar, antlr-2.7.6.jar, asm-attrs.jar, asm.jar, c3p0-0.9.0.jar, cglib-2.1.3.jar, commons-collections-2.1.1.jar, commons-collections-3.1.jar, commons-logging-1.0.4.jar, dom4j-1.6.1.jar, ejb3-persistence.jar, hibernate-annotations.jar, hibernate-commons-annotations.jar, hibernate-tools.jar, javassist-3.9.0.GA.jar, jta-1.1.jar, junit-3.8.1.jar, mysql-connector-java-5.1.7-bin.jar, slf4j-api-1.5.8.jar

Problem:

Eclipse states there's a problem starting in User.java, line number 12:

config.addAnnotatedClass(User.class);

"The type org.hibernate.MappingException cannot be resolved. It is indirectly referenced from required .class files"

"The project was not built since its build path is incomplete. Cannot find the class file for org.hibernate.MappingException. Fix the build path then try building this project examscam"

What am I possibly doing wrong?

Which jar file does org.hibernate.MappingException belong in?

Am I placing the config file in the right place (right under /examscam/src)?

[Cameron Wallace McKenzie]

Do you have the actual hibernate3.jar file?

On a vacation right now with limited net access. I'll get deeper into it if when I'm back on Tuesday.

-Cameron McKenzie

[James Dekker]

Yes, it was the hibernate3.jar which was missing...

Thank you! But, however, when Eclipse runs the program, it states this in the console:

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Exception in thread "main" java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder
	at org.slf4j.LoggerFactory.getSingleton(LoggerFactory.java:223)
	at org.slf4j.LoggerFactory.bind(LoggerFactory.java:120)
	at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:111)
	at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:269)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:242)
	at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:255)
	at org.hibernate.cfg.Configuration.<clinit>(Configuration.java:152)
	at com.examscam.app.TestApp.main(TestApp.java:11)
Caused by: java.lang.ClassNotFoundException: org.slf4j.impl.StaticLoggerBinder
	at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:319)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:330)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:254)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:402)
	... 8 more

I have the sl4j-api-1.5.8.jar in my Eclipse's build path... I wonder what I am doing wrong?

[Ravi Bansal]

Hi
if you go to webpage , you can see you need to one of the jars having the missing class.
I faced the same issue , i downloaded the jar slf4j-simple-1.5.8 and it worked for me afterwards

[James Dekker]

Hi Ravi,

I got it working last night (sorry for not posting an update to this thread earlier)...

The new problem I am having is that whereas this code does work and generate a table named User in the database, the logging isn't properly set up:

log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).
log4j:WARN Please initialize the log4j system properly.
drop table if exists User
create table User (id bigint not null auto_increment, password varchar(255), primary key (id))

I wrote this log4j.properties file and placed it under $PROJECT_DIR_ROOT and also put it under Eclipse's build path (and it still doesn't work):

### Direct log4j properties to STDOUT ###
lo4j.appender.stdout=org.apache.log4j.ConsoleAppender
lo4j.appender.stdout.Target=System.out
lo4j.appender.stdout.layout=org.apache.log4j.PatternLayout
lo4j.appender.stdout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### Set Log Levels - ###
log4j.rootLogger=warn, stdout log4j.logger.org.hibernate=info

### Log JDBC Bind Parameters ###
log4j.logger.org.hibernate.type=debug

### Log schema/export update ###
log4j.logger.org.hibernate.tool.hbm2ddl=debug

Any assistance is most appreciated...

[Vijitha Kumara]

James Dekker wrote:The new problem I am having is that whereas this code does work and generate a table named User in the database, the logging isn't properly set up:
I wrote this log4j.properties file and placed it under $PROJECT_DIR_ROOT and also put it under Eclipse's build path (and it still doesn't work):

It should be at the root of the classpath when the application is running so log4j can be initialized. Is it (don't know what you mean by $PROJECT_DIR_ROOT) ?

[James Dekker]

It is at the root of my project directory (/devprojects/examscam/)... However, I am using Eclipse and am not transferring it to PROJECT_DIR_ROOT/classes (output dir) where the code actually resides when compiled using Ant or Maven.

I even edited my CLASSPATH in .bash_profile to include this (in a separate folder):

export CLASSPATH=.:/devtools/jarlib/log4j.properties

And it still doesn't initialize the logging settings...

[Vijitha Kumara]

Which ever way you run the app, as I said before log4j.properties should be at the root of the classpath (you will have to copy the file in to the directory where you compile the other class files in to because that's where (probably) you set the classpath in order to run the application).

[James Dekker]

Is there a way to have Eclipse move the log4j.properties file to classes dir (Output dir) when one compiles the source files?

[James Dekker]

When I manually placed the log4j.properties files under classes dir, it actually loaded but it stated this error:

log4j:ERROR Could not find value for key log4j.appender.stdout log4j.logger.org.hibernate=info
log4j:ERROR Could not instantiate appender named "stdout log4j.logger.org.hibernate=info".
log4j:WARN No appenders could be found for logger (org.hibernate.tool.hbm2ddl.SchemaExport).
log4j:WARN Please initialize the log4j system properly.

log4j.properties file:

### Direct log4j properties to STDOUT ###
lo4j.appender.stdout=org.apache.log4j.ConsoleAppender
lo4j.appender.stdout.Target=System.out
lo4j.appender.stdout.layout=org.apache.log4j.PatternLayout
lo4j.appender.stdout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### Set Log Levels - ###
log4j.rootLogger=warn, stdout log4j.logger.org.hibernate=info

### Log JDBC Bind Parameters ###
log4j.logger.org.hibernate.type=debug

### Log schema/export update ###
log4j.logger.org.hibernate.tool.hbm2ddl=debug

I'll try again:

Does anyone know how to make Eclipse manually place the log4j.properties file into the output dir's top level root folder without using a build script?

Is there a jar file that I am not using which is making the logging errors (located above) occur?

[Cameron Wallace McKenzie]

This line:

### Set Log Levels - ###
log4j.rootLogger=warn, stdout log4j.logger.org.hibernate=info

Should be broken into two lines:

log4j.rootLogger=warn, stdout
log4j.logger.org.hibernate=info


That little pearl of wisdom is included in the "Hibernate Made Easy" book errata locate here:

http://www.hiberbook.com/HiberBookWeb/learn.jsp?tutorial=26errorfreecodechallenge
http://jpa.ezhibernate.com/Javacode/learn.jsp?tutorial=26errorfreecodechallenge

Here's the source code for the book Hibernate Made Easy too, which might help:

http://www.scja.com/hiberbook_source_beta.zip

-Cameron McKenzie

[James Dekker]

Hi Cameron,

Thanks for the direct response! I didn't know that the Comments section under your Error Free Code Challenge page is where the errata exists...

Followed your suggestion (by breaking it up into two lines) and now I have new log4 related errors:

log4j:ERROR Could not find value for key log4j.appender.stdout
log4j:ERROR Could not instantiate appender named "stdout".
log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).
log4j:WARN Please initialize the log4j system properly.

Either way, your book rocks! Since the pages are a smaller size, I've been able to read through most of it very quickly!

Makes me want to buy your other books!

-James

[Cameron Wallace McKenzie]

So, going back to my book, this was my little blurb on log4j:

Setting up log4J

You will also notice a little log4J error message in my output:

log4j:WARN No appenders could be found for logger
log4j:WARN Please initialize the log4j system properly.

This error is due to the fact that Hibernate is using Log4J, and a properties file that Log4J uses to initialize itself cannot be found on the classpath. The Hibernate core download contains a sample log4J.properties file you can place on your classpath that will eliminate this error message and subsequently direct logging entries to the System.out log. Alternatively, you can create your own log4J.properties file with the following settings:

### direct log messages to stdout ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout= org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern= %d{ABSOLUTE} %5p %c{1}:%L - %m%n
### set log levels - ###
log4j.rootLogger=warn, stdout
log4j.logger.org.hibernate=info
### log JDBC bind parameters ###
log4j.logger.org.hibernate.type=info
### log schema export/update ###
log4j.logger.org.hibernate.tool.hbm2ddl=debug

Make sure the file is named log4j.properties, and is placed on the classpath of the JVM. Then you'll get all sorts of crazy log messages!

But these messages are not normal:

log4j:ERROR Could not find value for key log4j.appender.stdout
log4j:ERROR Could not instantiate appender named "stdout".

Do you have a comment, extra comment, or missing ### marks in your log4j property file?

You know, you just might want to get the darn thing working first! Why not comment out each line in the log4j file and let Hibernate use its own defaults. You may get a warning message, but at least everything will run. Warnings are just that -warning:

### direct log messages to stdout ###
#log4j.appender.stdout=org.apache.log4j.ConsoleAppender
#log4j.appender.stdout.Target=System.out
#log4j.appender.stdout.layout= org.apache.log4j.PatternLayout
#log4j.appender.stdout.layout.ConversionPattern= %d{ABSOLUTE} %5p %c{1}:%L - %m%n
### set log levels - ###
#log4j.rootLogger=warn, stdout 
#log4j.logger.org.hibernate=info
### log JDBC bind parameters ###
#log4j.logger.org.hibernate.type=info
### log schema export/update ###
#log4j.logger.org.hibernate.tool.hbm2ddl=debug    

Let's get the Hibernate stuff working. I'd hate to see you fighting with log4j and not enjoying the real pleasure of Hibernate!

By the way, I just got back from my short vacation, so I should be more accessible here for help and book related questions.

-Cameron McKenzie

[James Dekker]

Hi Cameron,

Its now working!

If you scroll up (this thread) you'll notice that the first four lines were missing the "g" for log4j

Before:

# ### Direct log4j properties to STDOUT ###  
lo4j.appender.stdout=org.apache.log4j.ConsoleAppender  
lo4j.appender.stdout.Target=System.out  
lo4j.appender.stdout.layout=org.apache.log4j.PatternLayout  
lo4j.appender.stdout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n  

After (fixed):

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

I am almost done with the 7th chapter of your book - its not like I am stuck with the first chapter because of log4j config problems!

Already have most of the code running...

Its interesting that the the Session.load() and Session.get() methods automatically associate the instance with the session.

Here's my fixed log4j.properties file:

### Direct log4j properties to STDOUT ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

### Set Log Levels - ###
log4j.rootLogger=warn, stdout
log4j.logger.org.hibernate=info

### Log JDBC Bind Parameters ###
log4j.logger.org.hibernate.type=debug

### Log schema/export update ###
log4j.logger.org.hibernate.tool.hbm2ddl=debug

One last try, if anyone has read this thread, can they assist me in how to place the log4j.properties files automatically into PROJECT_DIR/classes using Eclipse (I've been manually moving it from the filesystem)?

-James

[Cameron Wallace McKenzie]

into PROJECT_DIR/classes using Eclipse (

Well, if it's in your source directory, it SHOULD be copied over automatically to the corresponding classes directory. Maybe if you do a build and clean?

-Cameron McKenzie

[James Dekker]

Well, it was outside my <src> dir, but directly underneath my PROJECT_DIR_ROOT...

e.g.

/examscam
|
------------- log4j.properties
|
-------------- /src
|
--------------/classes

By moving it under the /src directory, it worked!

I never knew about this because I always rely on an Ant build script which compiles, zips into a WAR file, and then deploys.

Many thanks to you, now I have it just like I want it!

[Cameron Wallace McKenzie]

I never knew about this because I always rely on an Ant build script which compiles, zips into a WAR file, and then deploys.

It's great when you're learning something like Hibernate, and as a side product, you get a deeper understanding of how peripheral technologies like ANT and Eclipse work. Good stuff!

-Cameron McKenzie