NullArgumentToVariableArgMethod

Reports calls to variable arity methods that have a single argument in the vararg parameter position, which is either a null or an array of a subtype of the vararg parameter. Such an argument may be confusing as it is unclear if a varargs or non-varargs call is desired.

Example:

String[] ss = new String[]{"foo", "bar"};
  System.out.printf("%s", ss);

In this example only the first element of the array will be printed, not the entire array.