Blank final fields : Final « Class « Java

Blank final fields

// :
// "Blank" final fields.
// From 'Thinking in Java, 3rd ed.' (c) Bruce Eckel 2002
// See copyright notice in CopyRight.txt.

class Poppet {
  private int i;

  Poppet(int ii) {
    i = ii;

public class BlankFinal {
  private final int i = 0; // Initialized final

  private final int j; // Blank final

  private final Poppet p; // Blank final reference

  // Blank finals MUST be initialized in the constructor:
  public BlankFinal() {
    j = 1; // Initialize blank final
    p = new Poppet(1); // Initialize blank final reference

  public BlankFinal(int x) {
    j = x; // Initialize blank final
    p = new Poppet(x); // Initialize blank final reference

  public static void main(String[] args) {
    new BlankFinal();
    new BlankFinal(47);
} ///:~


Related examples in the same category

1.Java Final variable: Once created and initialized, its value can not be changed
2.Experiment with final args to functionsExperiment with final args to functions
3.Using final with method arguments
4.The effect of final on fieldsThe effect of final on fields
5.Making an entire class final