def line = "test (HttpServletRequest request,String sessionId,@RequestBody(required = false) @ApiParam(\"PlatformFilterPost payload for filter.\")PlatformFilterPost platformFilterPost, test) {";

println(getMethodArguments(line))

def getMethodArguments(methodLine) {
    def methodSignature = getMethodSignature(methodLine);
    if (methodSignature) {
        def methodArguments = getMethodSignatureArguments(methodSignature);
        if (methodArguments) {
            return methodArguments;
        }
        else {
            return null;
        }
    }
    else {
        return null;
    }
}

def getMethodSignature(methodLine) {
    return methodLine.find( /\(([\s\S]+?)\)(?=[^()]*(\}|\{|;))/ ) {
        it[1];
    };
}

def getMethodSignatureArguments(methodSignature) {
    def matcher = methodSignature =~ /((?:(\@\w+\(.*?\))\s*?)*?(?:\w+)(?:\s+)(\w+)(\,|\s)*?)+/;
    def args = []
    while(matcher.find()){
        args.add(matcher.group().replaceAll(/(.+\s+)/,"").trim())
    };
    return args;
}