add files

WordBank.java

@@ -0,0 +1,47 @@
+import java.util.*;
+class WordBank {
+    private Set<String> wordBank = new HashSet<>();
+    private Random r = new Random();
+    static WordBank obj = new WordBank();
+
+    public int setSize() {
+        return (wordBank.size());
+
+    }
+
+    private WordBank() {
+    }
+
+    public static WordBank getObject() {
+        return obj;
+    }
+
+    public void addWord(String word) {
+
+        for (String i : wordBank) {
+            if (word.equals(i)) {
+                System.out.println("This word already exists! ");
+                return;
+
+            }
+        }
+        if (word == null || word.equals("")) {
+            System.out.println("Word is not valid!");
+            return;
+        }
+        wordBank.add(word);
+
+    }
+
+    public String getRandomWord() {
+        if (wordBank.size() == 0) {
+            System.out.println("there is no word in Word Bank \n");
+            return ("there is no word in Word Bank ");
+        }
+        Object[] wordBankArray = wordBank.toArray();
+        int a = r.nextInt(wordBankArray.length);
+
+        return ((String) wordBankArray[a]);
+
+    }
+}