The use of “this” in Java

Question

If I write the following class:

public class Example {

      int j;
      int k;

      public Example(int j, int k) {
           j = j;
           k = k;
          


        

Answer 1

If you don't write "this.variable" in your constructor, and if you have a local variable (including the function parameter) with the same name as your field variable in the constructor, then the local variable will be considered; the local variable shadows the field (aka class variable).

One place where "this" is the only way to go:

class OuterClass {
  int field;

  class InnerClass {
    int field;

    void modifyOuterClassField()
    {
      this.field = 10; // Modifies the field variable of "InnerClass"
      OuterClass.this.field = 20; // Modifies the field variable of "OuterClass",
                                  // and this weird syntax is the only way.
    }
  }
}