null specifies the type

class Tips0031 {
  public void someMethod() {

    //When calling an assignment statement or method, it is difficult to understand by simply writing null, so it is better to specify the type.
    //In the following cases, it is not necessary to specify it.
    String str = null;
    //
    //However, when the variable declaration and the assignment statement are separated, it is better to specify them.
    //
    //Other processing
    //
    str = (String)null;
    //
    //Also when calling a method
    otherMethod(null);
    //It is better to do as below than above
    otherMethod((String)null);
    //
  }
  //
  private void otherMethod(String str) {
    //Some processing
  }
}