Rule to match at least one constructors in exceptions that match ctor(cause, pattern, args) or ctor(pattern, args)

[dgroup]

class MyException extends Exception {
    public MyException(String pattern, Object ...args) {
         super(String.format(pattern, args));
   }

   public MyException(Throwable cause, String pattern, Object ...args) {
         super(String.format(pattern, args), cause);
   }
}

[dykov]

//ClassOrInterfaceDeclaration
[pmd-java:typeIs('java.lang.Exception')] (: extends Exception class :)
[
not(
./ClassOrInterfaceBody/ClassOrInterfaceBodyDeclaration/ConstructorDeclaration/FormalParameters[
    (: Ctor(Throwable, String, Object...) :)
    (./FormalParameter[1]/Type/ReferenceType/ClassOrInterfaceType[pmd-java:typeIs('java.lang.Throwable')]
    and
    ./FormalParameter[2]/Type/ReferenceType/ClassOrInterfaceType[pmd-java:typeIs('java.lang.String')]
    and
    ./FormalParameter[3][@Varargs=true()]/Type/ReferenceType/ClassOrInterfaceType[pmd-java:typeIsExactly('java.lang.Object')])

    or

    (: Ctor(String, Object...) :)
    (./FormalParameter[1]/Type/ReferenceType/ClassOrInterfaceType[pmd-java:typeIs('java.lang.String')]
    and
    ./FormalParameter[2][@Varargs=true()]/Type/ReferenceType/ClassOrInterfaceType[pmd-java:typeIsExactly('java.lang.Object')])] (: typeIs('java.lang.Object') can accept any class :)
)
]

[dykov]

@dgroup , should the rule throw violation for the following case?

class MyException extends Exception {
    public MyException(Exception cause, String pattern, Object... args) {
    }
}

Here we have Exception as a first constructor param, not Throwable

[dykov]

@dgroup , also should these constructors have strictly public modifier?

[dgroup]

Not sure about public, let's do not check it so far

[dykov]

@dgroup, so i suggest to check for non-private modifier?