First attempt as isUnique.

src/Main.java

@@ -1,15 +1,24 @@
+import java.util.HashSet;
+
 //TIP To <b>Run</b> code, press <shortcut actionId="Run"/> or
 // click the <icon src="AllIcons.Actions.Execute"/> icon in the gutter.
 public class Main {
     public static void main(String[] args) {
         //TIP Press <shortcut actionId="ShowIntentionActions"/> with your caret at the highlighted text
         // to see how IntelliJ IDEA suggests fixing it.
-        System.out.printf("Hello and welcome!");
-
-        for (int i = 1; i <= 5; i++) {
-            //TIP Press <shortcut actionId="Debug"/> to start debugging your code. We have set one <icon src="AllIcons.Debugger.Db_set_breakpoint"/> breakpoint
-            // for you, but you can always add more by pressing <shortcut actionId="ToggleLineBreakpoint"/>.
-            System.out.println("i = " + i);
+        System.out.println("Hello and welcome!\n");
+        System.out.println("Is 'test' unique: " + isUnique("test"));
+        System.out.println("is 'steak' unique: "+ isUnique("steak"));
+    }
+    public static boolean isUnique(String inputString)
+    {
+        HashSet testString = new HashSet(); //Maybe not hashSet?
+        for(int i = 0; i < inputString.length(); i++)
+        {
+            //still need to check format before add.
+            if (!(testString.add(inputString.charAt(i))))
+                return false;
         }
+        return true;
     }
 }