Checks for a duplicate import statements.
Checks for an import of a class that is within the same package as the importing class.
Checks for an import from any package that is already automatically imported for Groovy files. A Groovy file does not need to include an import for classes from java.lang, java.util, java.io, java.net, groovy.lang and groovy.util, as well as the classes java.math.BigDecimal and java.math.BigInteger.
Checks for import statements for classes that are never referenced within the source file. Also checks static imports.
Known limitations: