Android Gradle compiling commons-io creates duplicate in library tree

Question

I'm trying to build and maintain an old application for work but I can't get past the build phase. In my app/build.gradle file I have

dependencies { 
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.apache.commons:commons-io:1.3.2'
    //some more libraries compiled as well
}

but get the following error when trying to execute:

Error:Execution failed for task ':myApp'. com.android.build.api.transform.TransformException: java.util.zip.ZipException: duplicate entry: org/apache/commons/io/CopyUtils.class

This is almost certainly because when I compile that jar, at the top of my External Libraries tree, this is generated:

Why is this happening, and how can I get it to stop so I can complete the build?

Bihar

Answer 1

There is a simple way to exclude the double classes. At first you need to find out which dependency is causing that if you know that use this code:

compile('com.example:some-dependency:4.2') {
    exclude module: 'commons-io'
}

Dustheap

It appears to be commons-io itself. When I leave that out, both versions disappear from the library. I'll add the exclude to its own compilation but that seems to be kind of counterintuitive... – Bihar

I suspect it is the fault of this line: compile fileTree(dir: 'libs', include: ['*.jar']) do you have a libs directory with jars? – Dustheap

Answer 2

There is an option to fix it on gradle dependency resolution level

configurations.all {
    resolutionStrategy.dependencySubstitution {
        substitute module('org.apache.commons:commons-io:1.3.2') with module('commons-io:commons-io:1.3.2')
    }
}

Reason of the conflict is that org.apache.commons:commons-io:1.3.2 was pushed by mistake https://mcmap.net/q/580128/-what-is-the-difference-between-maven-dependencies-org-apache-commons-commons-io-and-commons-io-commons-io

You can see where dependency is coming from with

gradle :main:dependencyInsight --configuration compile --dependency commons-io

Hawthorn

Answer 3

I know that this thread is old enough, but if someone faces this issue, the reason may be in the artifact itself.

com.apache.commons:commons-io:XXX has been moved to commons-io:commons-io:XXX and fetching of the old artifact may produce unexpected behavior.

Lakia

Answer 4

It could be possible that other libraries in the project have the commons-io dependency causing duplicate entries.

See if this helps - Gradle Duplicate Entry: java.util.zip.ZipException

Momently

It doesn't appear that this is the case. I've looked at that question and ruled it out. Looking through all my other libraries there don't seem to be any dependencies on commons_io, so I can't imagine why this is happening. – Bihar