Add Java solution to 179. Largest Number

Author: gnohgnij

java/0179-largest-number.java

@@ -0,0 +1,26 @@
+class Solution {
+    public String largestNumber(int[] nums) {
+        String[] arr = new String[nums.length];
+
+        for(int i=0; i<nums.length; i++) {
+            arr[i] = String.valueOf(nums[i]);
+        }
+
+        Arrays.sort(arr, new Comparator<String>() {
+            @Override
+            public int compare(String s1, String s2) {
+                String n1 = s1 + s2, n2 = s2 + s1;
+                return n2.compareTo(n1);
+            }
+        });
+
+        if(arr[0].equals("0")) return "0";
+
+        StringBuilder sb = new StringBuilder();
+        for(String s : arr) {
+            sb.append(s);
+        }
+
+        return sb.toString();
+    }
+}