Gradle script: Classcast Exception in ant.copy task - gradle

Question

I have a Gradle script in which I need to copy a bunch of files from srcPath to tgtPath while specifying include and exclude patterns.
Normaly I would do this with Gradle's built-in copy task but here I also need to convert the character encoding while doing so. I thus am trying to use the ant.copy method because it supports "encoding" and "outputEncoding" arguments, which are supposed to support exactly such conversions.
So I defined me a method as follows:
private void copy(String srcPath, String tgtPath, includePatterns = ['**/*'], excludePatterns = []) {
println "copying from '${srcPath}' to '${tgtPath}' (incl:'${includePatterns}' / excl:'${excludePatterns}'):"
new AntBuilder().copy(todir: tgtPath,
encoding: StandardCharsets.ISO_8859_1,
outputEncoding: StandardCharsets.UTF_8) {
fileset(dir: srcPath,
includes: includePatterns,
excludes: excludePatterns)
}
}
When I execute this as part of my Gradle build (actually within a .groovy file which is why I am using "new AntBuilder.copy(...)" here instead of just "ant.copy(...)" I get the following exception:
java.lang.ClassCastException: org.apache.xerces.parsers.XIncludeAwareParserConfiguration cannot be cast to org.apache.xerces.xni.parser.XMLParserConfiguration
??? What has this to do with XML-parsing? I don't understand at all why I am getting this error.
I only found a couple of examples but no real documentation on how to use this method from Groovy. Ant's documentation claims that "includes" and "excludes" accepts lists of arguments which is what I am passing here. Any idea, what am I doing wrong here or why this doesn't work?
Or any other suggestion on how to convert character encodings while copying files over in Gradle?

Answer 1

I suggest that you use Gradle's built in ant integration.
Eg:
project.ant.copy(todir: tgtPath,
encoding: StandardCharsets.ISO_8859_1,
outputEncoding: StandardCharsets.UTF_8) {
fileset(dir: srcPath,
includes: includePatterns,
excludes: excludePatterns)
}