java Jar containing jars => java.lang.NoClassDefFoundError -> How to include .jar files

Question

jar file

when I run java -jar main.jar I get the following error:

The main class of the .jar file second.jar which is one of several libraries inside is not accessible.

I cannot rebuild the project since I just have the main.jar file.

How can I write a run.bat file or a mainifest.mf file that all .jar files that are contained in the main.jar file are accessible.

Here is the mainifest.mf file inside the main.jar:

Just include the dependencies in classpath by using -cp flag. java -cp dirToDependencyJars -jar main.jar — Manoj Vadehra, May 20 '19 at 10:54
And what is the directory if the jars are inside the main folder of the main jar ? — Viktor Carlson, May 20 '19 at 11:00
Interesting. I didn't notice that you had embedded jars. Here's a similar post: https://stackoverflow.com/questions/183292/classpath-including-jar-within-a-jar — Manoj Vadehra, May 20 '19 at 11:06

score 0 · Answer 1 · answered May 20 '19 at 11:22

There are following probable options for you to solve.

Manifest-Version: 1.0
Main-Class: com.comapany.product.MainClass
Class-Path: a.jar b.jar c.jar

java -cp a.jar;b.jar;c.jar com.comapany.product.MainClass

It is highly recommended to create a fat jar using Maven Shade plugin in case of Maven or Shadow plugin in case of Gradle.

1 Answers1