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bundled executable jar file - couldnot find main class

I am trying to execute a jar file StartupUtil.jar but it's giving an error of Couldnot find and load main class. I looked at other similar question and tried but couldnot figure out what is wrong.
My structure for created StartupUtil.jar is
->com.ihc.startup.util.StartupService
->META-INF/MANIFEST.MF
The content of MANIFEST is:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.9.2
Created-By: 1.7.0_79-b15 (Oracle Corporation)
Main-Class: com.ihc.startup.util.StartupService
Class-Path: C:\Users\tgupta12\workspace_new\IHC_Startup\lib\bson-3.0.1
.jar C:\Users\tgupta12\workspace_new\IHC_Startup\lib\mongodb-driver-3
.0.1.jar C:\Users\tgupta12\workspace_new\IHC_Startup\lib\mongodb-driv
er-core-3.0.1.jar C:\Users\tgupta12\workspace_new\IHC_Startup\classes
Here is my build.xml
<?xml version="1.0" encoding="UTF-8"?>
<project name="Startup" default="build" basedir=".">
<property file="./build.properties" />
<path id="lib-classpath">
<fileset dir="${libApp.dir}">
<include name="*.jar"/>
</fileset>
<pathelement path="${bin.dir}"/>
</path>
<target name="build" description="Compile main source tree java files">
<echo message=" Build Startup Utility" />
<mkdir dir="${bin.dir}"/>
<echo message=" Compiling source files" />
<javac destdir="${bin.dir}" source="${versionJDK}" target="${versionTarget}" debug="true"
deprecation="false" optimize="false" failonerror="true" includeantruntime="false">
<src path="${src.dir}"/>
<classpath refid="lib-classpath"/>
</javac>
<echo message=" ...Compilation of source files OK" />
<echo message=" Generating JAR for Startup - StartupUtility.jar" />
<delete file="${out.dir}/${startup-util-name}" />
<!-- convert classpath to a flat list/string -->
<pathconvert property="lib.classpath" pathsep=" ">
<path refid="lib-classpath" />
<!--<flattenmapper />-->
</pathconvert>
<jar destfile = "${out.dir}/${startup-util-name}" basedir = "${bin.dir}" includes = "**/*">
<manifest >
<attribute name="Class-Path" value="${lib.classpath}" />
<attribute name="Main-Class" value="com.ihc.startup.util.StartupService"/>
</manifest>
</jar>
<echo message=" ...JAR Created for Startup" />
</target>
<target name="run" depends="build">
<java jar="${out.dir}/${startup-util-name}" fork="true"/>
</target>
Below is my build.properties file:
#Directories
build.dir=build
src.dir=src
libApp.dir=lib
out.dir=out
web.dir=WebContent/WEB-INF
bin.dir=classes
webcontent.dir=WebContent
#File Name
war-file-name=StartupService.war
startup-util-name=StartupUtil.jar
#Target Properties
versionJDK=1.7
versionTarget=1.7
When it tries to execute the target run it gives
Error: Could not find or load main class com.ihc.startup.util.StartupService

I strongly suspect that the problem is it can't find the dependencies, which means it can't properly load the main class. I've never seen absolute filenames given in a manifest before, nor am I convinced about how you're breaking the lines (although that may be valid). Given how unportable it is to use the absolute filenames, I strongly suggest you just use relative ones.
Change your manifest to just:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.9.2
Created-By: 1.7.0_79-b15 (Oracle Corporation)
Main-Class: com.ihc.startup.util.StartupService
Class-Path: bson-3.0.1.jar mongodb-driver-3.0.1.jar mongodb-driver-core-3.0.1.jar
Then put those jar files in the same directory as StartupUtil.jar.

Ant not able to locate external jar files. Showing java.lang.NoClassDefFound Error exception

I am creating a jar file using following target -
<target name="jar" depends="compile">
<jar destfile="${jar.dir}/TargetClass.jar"
basedir="${build.dir}">
<manifest>
<attribute name="Main-Class" value="${main.class}"/>
</manifest>
</jar>
</target>
and I'm trying to execute the jar file using following target -
<target name="runjar">
<java jar="${jar.dir}/TargetClass.jar" fork="true"/>
</target>
I've used apache poi jar in my TragetClass which is located under D:/Jar directory. While executing it's not able to locate the poi jars and showing java.lang.NoClassDefFoundError exception.

You need to use a classpath. Something like:
<property name="poi.jars" value="path to poi jars"/>
<path id="run.classpath">
<pathelement location="${poi.jars}"/>
</path>
<target name="runjar">
<java
jar="${jar.dir}/TargetClass.jar"
fork="true"
<classpath refid="run.classpath"/>
/>
</target>
See Ant Java Task for more information.

Ant include external .jar

I want to include external jar to my java project. I'm using ant. External .jar is in folder lib. My build.xml looks something like that:
<?xml version="1.0" encoding="UTF-8"?>
<project>
<path id="classpath">
<fileset dir="lib" includes="**/*.jar"/>
</path>
<target name="clean">
<delete dir="build"/>
</target>
<target name="compile">
<mkdir dir="build"/>
<javac srcdir="src" destdir="build" classpathref="classpath" />
</target>
<target name="jar">
<mkdir dir="trash"/>
<jar destfile="trash/test.jar" basedir="build">
<zipgroupfileset dir="lib" includes="**/*.jar"/>
<manifest>
<attribute name="Main-Class" value="com.Test"/>
</manifest>
</jar>
</target>
<target name="run">
<java jar="trash/test.jar" fork="true"/>
</target>
</project>
But it doesn't work. When I want to import something from the external .jar, there is an error after command ant compile: package com.something does not exist.. What should I edit to get it working?
Exact error:
Compiling 23 source files to xy/build
xy/src/com/Test.java:5: package com.thoughtworks.xstream does not exist
import com.thoughtworks.xstream.*;
^
1 error

You should try without the includes attribute:
<fileset dir="lib" />
And in the jar part you include the classes like this:
<zipgroupfileset includes="*.jar" dir="lib"/>

You can't put external libraries into a jar and expect the classloader to use those jars. Unfortunately this is not supported.
There are ant tasks like one jar that help you, to create a jar file, that contains everything you need.
This bit is from the background information of one jar:
Unfortunately this is does not work. The Java Launcher$AppClassLoader
does not know how to load classes from a Jar inside a Jar with this
kind of Class-Path. Trying to use
jar:file:jarname.jar!/commons-logging.jar also leads down a dead-end.
This approach will only work if you install (i.e. scatter) the
supporting Jar files into the directory where the jarname.jar file is
installed.
Another approach is to unpack all dependent Jar files and repack them
inside the jarname.jar file. This approach tends to be fragile and
slow, and can suffer from duplicate resource issues.
Other Alternative:
jarjar: Jar Jar Links is a utility that makes it easy to repackage Java libraries and embed them into your own distribution

I also use ant to include a number of dependency JARs in my JAR. My compile task looks like this. Perhaps something similar will work for you.
<target name="compile" depends="init">
<javac srcdir="${src}" destdir="${build}" includeantruntime="false">
<classpath>
<pathelement path="${classpath}" />
<fileset dir="${deps}">
<include name="**/*.jar"/>
</fileset>
</classpath>
</javac>
<copy todir="${build}">
<fileset dir="${src}" excludes="**/*.java"/>
</copy>
</target>

sometimes u can use jar contents directly, just unzip
<unzip src="/Developer-Java/mysql-connector-java/mysql-connector-java-5.1.22-bin.jar" dest="${build_dir}" />

Java: Ant script works like a charm, but Jar throws exceptions

I created my first Ant script and it's working pretty well. It compiles all my java sources, creates a .jar file and runs the program without even any warning.
But when i try to run my .jar from command line i get NoClassDefFoundError exceptions.
So, how to translate this Ant snippet to work from command line?
<property name="main.class" value="de.bfs.radon.omsimulation.OMMainFrame"/>
<path id="classpath">
<fileset dir="${lib.dir}" includes="**/*.jar"/>
</path>
<target name="run" depends="jar">
<java fork="true" classname="${main.class}">
<classpath>
<path refid="classpath"/>
<path location="${bin.dir}/omsimulation-${version}.jar"/>
</classpath>
</java>
</target>
This is the command line:
# java -classpath lib/ -jar bin/omsimulation-0.4.45-beta3.jar
Throws:
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: com/toedter/calendar/JDateChooser
at de.bfs.radon.omsimulation.OMMainFrame.(OMMainFrame.java:133)
at de.bfs.radon.omsimulation.OMMainFrame$1.run(OMMainFrame.java:106)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
Why does my .jar file not work with the defined classpath? Further down the Ant script:
<target name="jar" depends="manifest">
<mkdir dir="${bin.dir}" />
<jar jarfile="${bin.dir}/omsimulation-${version}.jar" manifest="${src.dir}/omsimulation.manifest" compress="no" basedir="${build.dir}" includes="de/**" />
</target>
<target name="manifest" depends="compile">
<manifestclasspath property="manifest.cp" jarfile="${bin.dir}/omsimulation-${version}.jar">
<classpath refid="classpath" />
</manifestclasspath>
<manifest file="${src.dir}/omsimulation.manifest">
<attribute name="Built-By" value="${author}"/>
<attribute name="Main-Class" value="${main.class}"/>
</manifest>
</target>
Again, running the Ant script works fine. I even tried adding the said libraries to my .jar but that only blows up the file size, the problem still persists.
<jar jarfile="${bin.dir}/omsimulation-${version}.jar" manifest="${src.dir}/omsimulation.manifest" compress="no" basedir="${build.dir}"> <!-- includes="de/**" /-->
<fileset dir="${lib.dir}">
<include name="**/*.jar" />
</fileset>
</jar>
Any ideas on this?
Thanks a lot,
donc_oe
SOLVED: Thanks to perception, the unix command line i was looking for is:
# java -cp lib/*:bin/myjarfile.jar my.package.MyMainClass
And for Windows (note the ; semicolon):
# javaw -cp lib/*;bin/myjarfile.jar my.package.MyMainClass

The relevant thing to note from your build script is this:
<path id="classpath">
<fileset dir="${lib.dir}" includes="**/*.jar"/>
</path>
With that little snippet you have defined a path construct in Ant, which you then refer to in your run task:
<target name="run" depends="jar">
<java fork="true" classname="${main.class}">
<classpath>
<path refid="classpath"/>
<path location="${bin.dir}/omsimulation-${version}.jar"/>
</classpath>
</java>
</target>
This is in effect executing:
java -cp ${lib.dir}/*.jar:${bin.dir}/omsimulation-${version}.jar ${main.class}
Of course, it does so without the squigly lines and the path(s) fully substituted. The main point being that the command you are trying to run yourself is not equivalent at all. When attempting to invoke from the command line you will need to include in the classpath all the necessar JAR's containing your code and all third party libraries. Assuming everything is still bundled in the Ant created folders, something like:
java -cp <full-path-to-lib>/* -jar <full-path-to-bin>/omsimulation-0.4.45-beta3.jar
Or:
java -cp <full-path-to-lib?/*:<full-path-to-bin>/omsimulation-0.4.45-beta3.jar <MainClass>

ClassDefNotFoundException most likely occur when class is found in classpath, but it is loaded in different classloader, or in a wrong path etc.
From the build file, you appears to create jar that include other jars. This may not give a result you want.
Most likely you want a solution described in Easiest way to merge a release into one JAR file. My personal favorite is one-jar.

NoClassDefFound error for a jar created using ant build

I have a java project with class having main method in package com.nik.mypackage. Only one library is referenced which is someLib-5.0.2.jar
This library is in lib folder in eclipse and added to the build path.
I am creating executable jar of the application using the below ant script target:
<property name="src" location="src"/>
<property name="build" location="build"/>
<property name="dist" location="dist"/>
<target name="init">
<tstamp/>
<mkdir dir="${build}"/>
</target>
<target name="compile" depends="init"
description="compile the source " >
<javac srcdir="${src}" destdir="${build}">
<classpath>
<pathelement path="${classpath}"/>
<pathelement location="lib/someLib-5.0.2.jar"/>
</classpath>
</javac>
</target>
<target name="dist" depends="compile" description="generate the distribution" >
<!-- Create the distribution directory -->
<mkdir dir="${dist}/lib"/>
<copy todir="${build}/lib" verbose="true" file="lib/someLib-5.0.2.jar" />
<!-- Put everything in ${build} into the MyProject-${DSTAMP}.jar file -->
<jar jarfile="${dist}/lib/myProject-${DSTAMP}.jar" basedir="${build}">
<manifest>
<attribute name="Main-Class" value="com.nik.mypackage.MainClass"/>
<attribute name="Class-Path" value="../lib/someLib.jar"/>
</manifest>
</jar>
</target>
The jar MyProject-20111126.jar is getting created. However, running the below command:
c:>java -jar MyProject-20111126.jar
is throwing a NoClassDefFoundError for a class in someLib.jar
What am I doing wrong ??
Thanks for reading!

When you run where is someLib.jar relative to the MyProject-20111126.jar?
The classpath you are setting up in the MyProject.jar is telling the VM to look for a lib folder in the parent directory of MyProject.jar.
The ClassPath entry in the manifest is interpreted relative to the location of the JAR file. It is used to locate jar files on the File System. The regular class loader in JAVA does not support JAR files bundled inside of JAR files.

As mentioned in the comment by Eric Rosenberg, we can not nest jar files inside other jar files. So we need to deflat the library and bundle individual classes in the app jar.