.jar file do not contain Main-Class attribute in manifest.mf

Question

I am trying to run jar file through

java -jar jts.jar

but it is unable to run because it's Manifest.mf do not contain 'Main-Class' attribute, which is necessary for a jar file to run.

I am have same problem with 9-10 .jar files. Help me with how to find those mainclass in jar files, there is no any directly defined mainclass in jar file. How should I find the correct mainclass and how should I add it to manifest.mf

If there is no main class defined in the jar, they are probably not meant to be executed. — Henry, Nov 03 '13 at 06:08

score 0 · Answer 1 · answered Nov 03 '13 at 06:05

On command line you can use following command to generate jar having existing manifest.

jar cvfm MyJarName.jar manifest.txt *.class

Refer this page for more details.

Alternatively, if you are using eclipse. Please follow steps mentioned here to export jar.

score 0 · Answer 2 · answered Oct 29 '21 at 20:05

0

if you have your Main-Class attribute on the last line of your manifest.txt, it vanishes if you do not have a new line at the end. Very annoying, but always make sure you have a new line at the end of your manifest file.

answered Oct 29 '21 at 20:05

ooocp

1

score -1 · Answer 3 · answered Nov 03 '13 at 06:16

-1

1. You can open the jar file with winzip or winrar. 
2. Open manifest file in notepad. 
3. Add main-class: ClassNameContianingMainMethod. 
4. Save the file and then run it

answered Nov 03 '13 at 06:16

Bhushan

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.jar file do not contain Main-Class attribute in manifest.mf

3 Answers3