@Test
 public void testDecode() {
   binarymap = coder.binaryCodeGen(coder.buildTree(coder.freqMap(message)));
   System.out.println("Decoded String: " + coder.decode(binarymap, coder.encode(message)));
   System.out.println("Origin Message: " + message);
 }
 @Test
 public void testEncode() {
   encodedMessage = coder.encode(message);
   System.out.println("Encoded message: " + encodedMessage);
   System.out.println("Encoded bit string length: " + encodedMessage.length());
 }