diff --git a/java/217-Contains-Duplicate.java b/java/217-Contains-Duplicate.java
new file mode 100644
index 000000000..9c59be683
--- /dev/null
+++ b/java/217-Contains-Duplicate.java
@@ -0,0 +1,11 @@
+class Solution {
+    public boolean containsDuplicate(int[] nums) {
+        Set<Integer> numbers = new HashSet<Integer>();
+        for (int num : nums) {
+            if (numbers.contains(num)) return true;
+            numbers.add(num);
+        }
+        
+        return false;
+    }
+}
\ No newline at end of file
diff --git a/java/242-Valid-Anagram.java b/java/242-Valid-Anagram.java
new file mode 100644
index 000000000..83aa38541
--- /dev/null
+++ b/java/242-Valid-Anagram.java
@@ -0,0 +1,19 @@
+class Solution {
+    public boolean isAnagram(String s, String t) {
+        if (s.length() != t.length()) return false;
+        
+        int[] countS = new int[26];
+        int[] countT = new int[26];
+        
+        for (int i = 0 ; i < s.length() ; i++) {
+            countS[s.charAt(i) - 'a']++;
+            countT[t.charAt(i) - 'a']++;
+        }
+        
+        for (int i = 0 ; i < 26 ; i++) {
+            if (countS[i] - countT[i] != 0) return false;
+        }
+        
+        return true;
+    }
+}
\ No newline at end of file