Przykład Referencje

src/main/java/p05_klasy_wstep/Referencje1.java

+package p05_klasy_wstep;
+
+public class Referencje1 {
+    public static void main(String[] args) {
+        Osoba ala = new Osoba("Ala", "Kowalska", 30);
+        Osoba ola = new Osoba("Ola", "Malinowska", 40);
+        Konto a = new Konto(1, ala, 1000);
+        Konto b = new Konto(2, ola, 2000);
+        Konto c = b;
+
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println();
+
+        b.wplata(48);
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println();
+
+        b = a;
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println();
+
+        // tracimy dowiązanie do Konto nr 2
+        c = b;
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println();
+
+        a = null;
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println();
+
+        c = b = a;
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+    }
+}

src/main/java/p05_klasy_wstep/Referencje2.java

+package p05_klasy_wstep;
+
+public class Referencje2 {
+
+    static void test(Konto a, Konto b, Konto c, int x) {
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println("x: " + x);
+        System.out.println();
+
+        x += 55;
+        b.wplata(44);
+        a = new Konto(a.numer, a.wlasciciel, a.saldo);
+        a.wplata(33);
+        a.wlasciciel.imie = "Alicja";
+
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println("x: " + x);
+        System.out.println();
+    }
+
+    public static void main(String[] args) {
+        Osoba ala = new Osoba("Ala", "Kowalska", 30);
+        Osoba ola = new Osoba("Ola", "Malinowska", 40);
+        Konto a = new Konto(1, ala, 1000);
+        Konto b = new Konto(2, ola, 2000);
+        Konto c = b;
+        int x = 5000;
+
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println("x: " + x);
+        System.out.println();
+
+        test(a, b, c, x);
+
+        System.out.println("a: " + a);
+        System.out.println("b: " + b);
+        System.out.println("c: " + c);
+        System.out.println("x: " + x);
+    }
+}