Simpliest way to add an attribute to a jar Manifest in Maven

Question

Since the last Java update, I need to tag my applet jars manifest with the Trusted-Library attribute to avoid warning popup when javascript is communicating wit

Answer 1

You can do that with the Maven JAR Plugin during the creation of the JAR file. Add the following to your pom.xml:

    org.apache.maven.plugins
    maven-jar-plugin
    
        
            false
            
                true
            
        
    


    org.apache.maven.plugins
    maven-jarsigner-plugin
    1.2
    
        
            sign
            
                sign
            
        
    
    
        /path/to/testkeystore
        myalias
        test123
    

The main attributes as specified in the JAR File Specification are available as dedicated elements, e.g.:

    org.apache.maven.plugins
    maven-jar-plugin
    
        
            false
            
                true
                true
            
            
                true
            
        
    

See the Maven Archiver Reference for further information.

To modify the manifest inside an existing jar file create a text file, e.g. mymanifest.mf which contains the required properties:

Trusted-Library: true

You can add the attributes of this file to an existing jar by executing the following command:

jar -cfm file-to-be-modified.jar mymanifest.mf

This will modify the manifest.mf inside the given jar.