Question

I am new to java and have used it in netBeans but have never tried to compile or run it from terminal. So, my question may look naive. I have a directory of this structure:

Folder X contains:
couple of files and a folder named esa-lucene.

esa-lucene is a directory having three folders src, lib, web:

.classpath, lib, .project, .settings, src, web

and I am trying to run a java file ” ESAWikipediaIndexer.java” which exists in this subdirectory:

X/esa-lucene/src/edu/wiki/index/ESAWikipediaIndexer.java

I cd into Folder X and use this:

java -cp esa-lucene.jar edu.wiki.index.ESAWikipediaIndexer

But it gives me this error:

Exception in thread "main" java.lang.NoClassDefFoundError: edu/wiki/index/ESAWikipediaIndexer
Caused by: java.lang.ClassNotFoundException: edu.wiki.index.ESAWikipediaIndexer
    at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Could not find the main class: edu.wiki.index.ESAWikipediaIndexer. Program will exit.

also I’ve checked .classpath and it contains:

<?xml version="1.0" encoding="UTF-8"?>
<classpath>
    <classpathentry kind="src" path="src"/>
    <classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
    <classpathentry kind="lib" path="lib/servlet-api.jar"/>
    <classpathentry kind="lib" path="web/WEB-INF/lib/lucene-analyzers-3.0.0.jar"/>
    <classpathentry kind="lib" path="web/WEB-INF/lib/lucene-core-3.0.0.jar"/>
    <classpathentry kind="lib" path="web/WEB-INF/lib/mysql-connector-java-5.1.12-bin.jar"/>
    <classpathentry kind="lib" path="web/WEB-INF/lib/trove-2.1.0.jar"/>
    <classpathentry kind="output" path="bin"/>
</classpath>

I’ve checked the lib and web/WEB-INF/lib/ folders as well and all the required external libraries (jar files) also exist in this folder.

I searched to find any solution and tried a couple of things but none of them worked. Have no clue how to make it work!

BTW, apparently people have used this package before, and I just downloaded to use it too but wasn’t successful so far.

Answer 1

Looks like you are referring to Eclipse classpath and .project files. That being the case why dont you try running it in eclipse.

However since here you are running it manually the classpath entries in classpath file are not being used. Also can you tell us where the .class file for the ESAWikipediaIndexer.java. If you run the below command

java -cp */esa-lucene.jar edu.wiki.index.ESAWikipediaIndexer

From the directory where it is located, it should work.
Also you need to provide full path or relative path to esa-lucene.jar in the above command.