Why can't run?

[Yancy cheng]

Hi,guys. i meet an error:
Successful:
C:\test>java -jar Test.jar
INFO (Test) - haha

Failure:
C:\test>ant -buildfile test.xml
run:
[java] java.lang.NoClassDefFoundError: org/apache/log4j/Logger
[java] at Test.<clinit>(Unknown Source)
[java] Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Logger
[java] at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
[java] at java.security.AccessController.doPrivileged(Native Method)
[java] at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
[java] at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
[java] at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
[java] at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
[java] ... 1 more
[java] Could not find the main class: Test. Program will exit.
[java] Exception in thread "main"
[java] Java Result: 1

test.xml:
<target name="run" depends="">
<java jar="Test.jar" fork="true"/>
</target>

why? i am trying to solve it two days, please for help.

[Christophe Verré]

Ant cannot find log4j's library. You have to set the classpath dependencies in your build.xml. Check this tutorial (Using external libraries).

[Yancy cheng]

Christophe Verré wrote:Ant cannot find log4j's library. You have to set the classpath dependencies in your build.xml. Check this tutorial (Using external libraries).

Hi,thanks for your reply. i know what you mean. but you can see the first runs ok, but the second runs meeting an error. why?
my Test.jar contains below:
Test.class
log4j-1.2.14.jar
log4j.properties
META-INF

i still confused.thank you.

[Christophe Verré]

Where is your manifest file ? What does it contain ?

[Campbell Ritchie]

Welcome to the Ranch I see this thread has been (correctly) moved to the "ANT" forum.

[Yancy cheng]

Christophe Verré wrote:Where is your manifest file ? What does it contain ?

Thanks very much for your kindly reply. my project works all right now, but i still have some questions to ask you.
build.xml

  
<?xml version="1.0"?>
<project name="funforfree" default="run" basedir=".">	
	<!--project direcyories-->
	<property name="src.dir" value="src"/>
	<property name="dist.dir" value="dist"/>
	<property name="doc.dir" value="doc"/>
	<property name="lib.dir" value="lib"/>
	<!--temporary dicectories-->
	<property name="build.dir" value="build"/>
	<property name="build.classes" value="${build.dir}/classes"/>
	<property name= "build.doc" value="${build.dir}/doc"/>
	<property name= "build.lib" value="${build.dir}/lib"/>
	<property name ="Main-class" value="Test"/>
	
	<!--Global settings-->
	<property name="javac.debug" value="on"/>
	<property name="build.compile" value="modern"/>
	<path id="classpath">
		<fileset dir="${lib.dir}">
			<include name="**/*.jar"/>
		</fileset>
	</path>
	
	<target name="prepare">
		<mkdir dir="${build.dir}"/>
		<mkdir dir="${build.classes}"/>
		<mkdir dir="${build.lib}"/>
		<mkdir dir="${lib.dir}"/>
		<tstamp/>
		<echo message="${TSTAMP}"/>
	</target>
	
	<target name="compile" depends="prepare">
		<!--Compile the application classes,not the module classes-->
		<javac destdir="${build.classes}" debug="${debug.flag}" deprecation="on">
			<src path="${src.dir}"/>
			<classpath refid="classpath"/>
		</javac>
		<copy todir="${build.classes}">
			<fileset dir="${src.dir}" excludes="**/*.java"/>
		</copy>
		<!--Package the application into a JAR-->
		<jar jarfile="${build.lib}/${Main-class}.jar" basedir="${build.classes}">
			<manifest> 
				<attribute name="Built-by" value="Yancy"/>
            	<attribute name="Main-class" value="${Main-class}"/> 
        	</manifest>
		</jar>
	</target>
	
	<target name="run" depends="compile">
		<!--java jar="${build.lib}/${Main-class}.jar" fork="true"/-->
		<java classname="${Main-class}" fork="true">
			<classpath>
				<path refid="classpath"/>
				<path location="${build.lib}/${Main-class}.jar"/>
			</classpath>
		</java>
	</target>
	
	<!-- Delete class files built during previous builds-->
	<target name="clean">
		<delete>
			<fileset dir="${build.classes}" includes="**/*.class"/>
		</delete>
	</target>
	
	
	<!-- Delete any created directories and their contents-->
	<target name="cleanall" depends="clean">
		<delete dir="${build.dir}"/>
		<!--delete dir="${doc.dir}"/-->
		<!--delete dir="${dist.dir}"-->
	</target>
</project>

please see run target: when i used <java jar="${build.lib}/${Main-class}.jar" fork="true"/> i will meet the "NoClassDefFoundError", why,even i have modified the

   
<jar jarfile="${build.lib}/${Main-class}.jar" basedir="${build.classes}">
    <manifest> 
	<attribute name="Built-by" value="Yancy"/>
        <attribute name="Main-class" value="${Main-class}"/> 
        <attribute name="Class-path" value="${lib.dir}"/>
     </manifest>
</jar>

[Yancy cheng]

Campbell Ritchie wrote:Welcome to the Ranch I see this thread has been (correctly) moved to the "ANT" forum.

yes,you are right, it's a mistake. i am fresher.

[Christophe Verré]

You still have to set the dependency in your MANIFEST file. Try to use this instead :

		<jar jarfile="${build.lib}/${Main-class}.jar" basedir="${build.classes}">
			<manifest> 
				<attribute name="Built-by" value="Yancy"/>
            	<attribute name="Main-class" value="${Main-class}"/> 
            	<attribute name="Class-Path" value="log4j-1.2.14.jar" />
        	</manifest>
		</jar>

[Yancy cheng]

Christophe Verré wrote:You still have to set the dependency in your MANIFEST file. Try to use this instead :

		<jar jarfile="${build.lib}/${Main-class}.jar" basedir="${build.classes}">
			<manifest> 
				<attribute name="Built-by" value="Yancy"/>
            	<attribute name="Main-class" value="${Main-class}"/> 
            	<attribute name="Class-Path" value="log4j-1.2.14.jar" />
        	</manifest>
		</jar>

Hi,if follow this, it is still wrong. whatever i modify.

    
<jar jarfile="${build.lib}/${Main-class}.jar" basedir="${build.classes}">
	<fileset dir="${lib.dir}" includes="**/*.jar"/>
	<manifest> 
		<attribute name="Built-by" value="Yancy"/>
            	<attribute name="Main-class" value="${Main-class}"/> 
            	<attribute name="Class-Path" value="log4j-1.2.14.jar" />//or "${lib.dir}/log4j-1.2.14.jar" still the same
        </manifest>
</jar>

<target name="run" depends="compile">
	<java jar="${build.lib}/${Main-class}.jar" fork="true">
	<!--java classname="${Main-class}" fork="true"-->
		<classpath>
			<path refid="classpath"/>
			<path location="${build.lib}/${Main-class}.jar"/>
			<path location="${lib.dir}/log4j-1.2.14.jar"/> //have or not have, still the same.
		</classpath>
	</java>
</target>

why?
Test.jar contains below:
Test.class Log4j.properties log4j-1.2.14.jar META-INF
MANIFEST.MF contains below:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.7.1
Created-By: 17.0-b17 (Sun Microsystems Inc.)
Built-by: Yancy
Main-class: Test
Class-Path: log4j-1.2.14.jar
what's wrong? thanks a lot.

[Christophe Verré]

Try "java classname="${Main-class}" fork="true"" instead of "java jar="${build.lib}/${Main-class}.jar" fork="true"".

It would be so much simplier if you kept the log4j JAR outside of your own JAR Do you need to put it inside ?

[Yancy cheng]

Christophe Verré wrote:Try "java classname="${Main-class}" fork="true"" instead of "java jar="${build.lib}/${Main-class}.jar" fork="true"".

It would be so much simplier if you kept the log4j JAR outside of your own JAR Do you need to put it inside ?

you are very kind! Thanks very much. but i still want to know why? Because when i go deep into the question, i find a more confused problem:
i move the Test.jar to the C:\test

Test.jar contains: Test.class Log4j.properties META-INF

MANIFEST.MF contains below:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.7.1
Created-By: 17.0-b17 (Sun Microsystems Inc.)
Built-by: Yancy
Main-Class: Test

(no dependency on log4j.jar)
Successful:
C:\test>java -jar Test.jar
INFO (Test) - haha


Failure:
C:\Java\jdk1.6.0_21\bin>java.exe -jar C:\test\Test.jar
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at Test.<clinit>(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Logger
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
... 1 more
Could not find the main class: Test. Program will exit.

it makes me so surprised! i just want to know why?

[Raymond Tong]

Because your log4j jar is located in C:\test
Execute C:\Java\jdk1.6.0_21\bin>java.exe -jar C:\test\Test.jar
would not include the log4j libaray
Execute C:\test>java -jar Test.jar
would do because the log4j library is on the current path "C:\test"

[Yancy cheng]

Raymond Tong wrote:Because your log4j jar is located in C:\test
Execute C:\Java\jdk1.6.0_21\bin>java.exe -jar C:\test\Test.jar
would not include the log4j libaray
Execute C:\test>java -jar Test.jar
would do because the log4j library is on the current path "C:\test"

thanks for you reply, but log4j.jar is not located in C:\test,it is not as easily as you think. i put log4j.jar to the jre/lib/exc. So the two ways of execute should be the same, but the results are quite different, i wanna to see why? thanks all the same~

[Martijn Verburg]

Hi Yancy,

Just so you know it's really not recommended to put 3rd party JARs in the JRE folders, they should be kept elsewhere and referenced as needed .

[Yancy cheng]

Martijn Verburg wrote:Hi Yancy,

Just so you know it's really not recommended to put 3rd party JARs in the JRE folders, they should be kept elsewhere and referenced as needed .

yes,you are right,very thanks~