"Invalid signature file" when attempting to run a .jar

The solution listed here might provide a pointer.

Invalid signature file digest for Manifest main attributes

Bottom line :

It's probably best to keep the official jar as is and just add it as a dependency in the manifest file for your application jar file.

I faced the same issue, after reference somewhere, it worked as below changing:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>3.2.1</version>
    <configuration>
        <createDependencyReducedPom>false</createDependencyReducedPom>
    </configuration>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <filters>
                    <filter>
                        <artifact>*:*</artifact>
                        <excludes>
                            <exclude>META-INF/*.SF</exclude>
                            <exclude>META-INF/*.DSA</exclude>
                            <exclude>META-INF/*.RSA</exclude>
                        </excludes>
                    </filter>
                </filters>
            </configuration>
        </execution>
    </executions>
</plugin>

I've recently started using IntelliJ on my projects. However, some of my colleagues still use Eclipse on the same projects. Today, I've got the very same error after executing the jar-file created by my IntelliJ. While all the solutions in here talking about almost the same thing, none of them worked for me easily (possibly because I don't use ANT, maven build gave me other errors which referred me to http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException, and also I couldn't figure out what are the signed jars by myself!)

Finally, this helped me

zip -d demoSampler.jar 'META-INF/*.SF' 'META-INF/*.RSA' 'META-INF/*SF'

Guess what's been removed from my jar file?!

deleting: META-INF/ECLIPSE_.SF 
deleting: META-INF/ECLIPSE_.RSA

It seems that the issue was relevant to some eclipse-relevant files.

I had the same issue in gradle when creating a fat Jar; updating the build.gradle file with an exclude line corrected the problem.

jar {
    from {
        configurations.compile.collect {
            it.isDirectory() ? it : zipTree(it)
        }
    }
    exclude 'META-INF/*.RSA', 'META-INF/*.SF','META-INF/*.DSA'
    manifest {
        attributes 'Main-Class': 'com.test.Main'
    }
}

In case you're using gradle, here is a full farJar task:

version = '1.0'
//create a single Jar with all dependencies
task fatJar(type: Jar) {
    manifest {
        attributes 'Implementation-Title': 'Gradle Jar File Example',  
            'Implementation-Version': version,
            'Main-Class': 'com.example.main'
    }
    baseName = project.name + '-all'
    from { configurations.compile.collect { it.isDirectory() ? it : zipTree(it) } }
    exclude 'META-INF/*.RSA', 'META-INF/*.SF','META-INF/*.DSA' 
    with jar
}

If you are looking for a Fat JAR solution without unpacking or tampering with the original libraries but with a special JAR classloader, take a look at my project here.

Disclaimer: I did not write the code, just package it and publish it on Maven Central and describe in my read-me how to use it.

I personally use it for creating runnable uber JARs containing BouncyCastle dependencies. Maybe it is useful for you, too.

You can use Shadow to generate a jar.

Shadow is a Gradle plugin for combining a project's dependency classes and resources into a single output Jar. The combined Jar is often referred to a fat-jar or uber-jar.

1. Modify build.gradle

   plugins {
       ...
       // ① Add the shadow plugin
       id "com.github.johnrengelman.shadow" version "5.2.0"
   }
   
   ...
   // ② Config the shadow jar, its name is baseName-1.0-classifier.jar
   shadowJar {
       archiveBaseName.set('baseName')
       archiveClassifier.set('classifier')
       archiveVersion.set('1.0')
       manifest {
           attributes 'Main-Class': 'Main'
       }
   }
   
   // ③ Disable the default jar task
   jar.enabled = false
   // ④ Execute the shadowJar task when compiling
   build.dependsOn(shadowJar)
   

2. Execute the command gradle build, the jar file will be generated:

   • <Project Directory>/build/libs/baseName-1.0-classifier.jar

For those who have trouble with the accepted solution, there is another way to exclude resource from shaded jar with DontIncludeResourceTransformer:

https://maven.apache.org/plugins/maven-shade-plugin/examples/resource-transformers.html#DontIncludeResourceTransformer

          <transformers>
            <transformer implementation="org.apache.maven.plugins.shade.resource.DontIncludeResourceTransformer">
                <resource>BC1024KE.DSA</resource>
            </transformer>
          </transformers>

From Shade 3.0, this transformer accepts a list of resources. Before that you just need to use multiple transformer each with one resource.

This happened to me in Intellij when I clicked "Add as a Maven Project" on bottom line when Intellij said "non-managed pom files found.". Meanwhile out folder was already generated. So it did not get recent changes.

Deleting out folder and running the program solved the issue for me. out folder was then recreated.

See the answer of Little Fox as well. The error I received was very similar to his.