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javagradlemanifest

Read manifest from JAR with gradle


How it is possible to read the manifest from a jar dependency in gradle? I want to print out this information

I didn't find a solution for that.

Best regards


Solution

  • It is possible. Here's a quick example I came up with using the Kotlin DSL:

    dependencies {
        implementation("org.apache.commons:commons-lang3:3.9")
    }
    
    val readManifest by tasks.registering {
        doLast {
            val archive = configurations["compileClasspath"].filter {
                // This will be list of resolved jars, so filter on the jar name.
                it.name.startsWith("commons-lang3")
            }
            val version = resources.text.fromArchiveEntry(archive, "META-INF/MANIFEST.MF")
            println(version.asString())
        }
    }
    

    Output of the task is:

    > Task :readManifest
    Manifest-Version: 1.0
    Created-By: Apache Maven Bundle Plugin
    Built-By: chtompki
    Build-Jdk: 11.0.2
    Specification-Title: Apache Commons Lang
    Specification-Version: 3.9
    Specification-Vendor: The Apache Software Foundation
    Implementation-Title: Apache Commons Lang
    Implementation-Version: 3.9
    Implementation-Vendor-Id: org.apache.commons
    Implementation-Vendor: The Apache Software Foundation
    Implementation-URL: http://commons.apache.org/proper/commons-lang/
    Automatic-Module-Name: org.apache.commons.lang3
    Bnd-LastModified: 1554946229157
    Bundle-Description: Apache Commons Lang, a package of Java utility class
     es for the  classes that are in java.lang's hierarchy, or are considere
     d to be so  standard as to justify existence in java.lang.
    Bundle-DocURL: http://commons.apache.org/proper/commons-lang/
    Bundle-License: https://www.apache.org/licenses/LICENSE-2.0.txt
    Bundle-ManifestVersion: 2
    Bundle-Name: Apache Commons Lang
    Bundle-SymbolicName: org.apache.commons.lang3
    Bundle-Vendor: The Apache Software Foundation
    Bundle-Version: 3.9.0
    Export-Package: org.apache.commons.lang3;version="3.9",org.apache.common
     s.lang3.arch;version="3.9",org.apache.commons.lang3.builder;version="3.
     9",org.apache.commons.lang3.concurrent;version="3.9",org.apache.commons
     .lang3.event;version="3.9",org.apache.commons.lang3.exception;version="
     3.9",org.apache.commons.lang3.math;version="3.9",org.apache.commons.lan
     g3.mutable;version="3.9",org.apache.commons.lang3.reflect;version="3.9"
     ,org.apache.commons.lang3.text;version="3.9",org.apache.commons.lang3.t
     ext.translate;version="3.9",org.apache.commons.lang3.time;version="3.9"
     ,org.apache.commons.lang3.tuple;version="3.9"
    Include-Resource: META-INF/NOTICE.txt=NOTICE.txt,META-INF/LICENSE.txt=LI
     CENSE.txt
    Require-Capability: osgi.ee;filter:="(&(osgi.ee=JavaSE)(version=1.8))"
    Tool: Bnd-4.1.0.201810181252
    

    The implementation configuration is not resolvable, so the compileClasspath is used instead since it is resolvable. You can see the configuration tree here