BAEL-1997 state design pattern in Java (#4827)

* BAEL-1997 state design pattern in Java

* BAEL-1997 different example code

* BAEL-1997 add additional method to the states

* BAEL-1997 clean up in ReceivedState

patterns/design-patterns/src/main/java/com/baeldung/state/ReceivedState.java

@@ -0,0 +1,24 @@
+package com.baeldung.state;
+
+public class ReceivedState implements PackageState {
+
+    @Override
+    public void next(Package pkg) {
+        System.out.println("This package is already received by a client.");
+    }
+
+    @Override
+    public void prev(Package pkg) {
+        pkg.setState(new DeliveredState());
+    }
+
+    @Override
+    public void printStatus() {
+        System.out.println("Package was received by client.");
+    }
+
+    @Override
+    public String toString() {
+        return "ReceivedState{}";
+    }
+}