in src/main/java/org/apache/maven/plugins/jar/AbstractJarMojo.java [199:210]
protected File getJarFile(File basedir, String resultFinalName, String classifier) {
if (basedir == null) {
throw new IllegalArgumentException("basedir is not allowed to be null");
}
if (resultFinalName == null) {
throw new IllegalArgumentException("finalName is not allowed to be null");
}
String fileName = resultFinalName + (hasClassifier() ? "-" + classifier : "") + ".jar";
return new File(basedir, fileName);
}