Changed module name. (#13098)

patterns-modules/design-patterns-singleton/src/main/java/com/baeldung/serializable_singleton/EnumSingleton.java

@@ -0,0 +1,20 @@
+package com.baeldung.serializable_singleton;
+
+public enum EnumSingleton {
+
+    INSTANCE("State Zero");
+
+    private String state;
+
+    private EnumSingleton(String state) {
+        this.state = state;
+    }
+
+    public static EnumSingleton getInstance() {
+        return INSTANCE;
+    }
+
+    public String getState() { return this.state; }
+
+    public void setState(String state) { this.state = state; }
+}

patterns-modules/design-patterns-singleton/src/main/java/com/baeldung/serializable_singleton/Singleton.java

@@ -0,0 +1,28 @@
+package com.baeldung.serializable_singleton;
+
+import java.io.Serializable;
+
+public class Singleton implements Serializable {
+
+    private static Singleton INSTANCE;
+    private String state = "State Zero";
+
+    private Singleton() {        
+    }
+    
+    public static Singleton getInstance() {
+        if(INSTANCE == null) {
+            INSTANCE = new Singleton();
+        }
+        
+        return INSTANCE;
+    }
+
+    public String getState() {
+        return state;
+    }
+
+    public void setState(String state) {
+        this.state = state;
+    }
+}