Hello. I am trying to encrypt and decrypt a file using symmetric encryption. However, when I try to decrypt, I get an exception: Input length must be multiple of 8 when decrypting with padded cipher. How do I resolve this?

Here is my code:

Java Code:
public static void symmetricEncrypt(String filename) {
		try {
			File file = new File(filename);
			int len = (int)file.length();
			byte[] input = new byte[len];
			FileInputStream fis = new FileInputStream(file);
			int b = fis.read();
			int i = 0;
			while(b != -1) {
				input[i] = (byte)b;
				i++;
				b = fis.read();
			}
			fis.close();

			SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede");
			Cipher cipher = Cipher.getInstance("DESede");
	
			byte[] cipherText = new byte[input.length];
			cipher.init(Cipher.ENCRYPT_MODE, key);
			cipher.init(Cipher.ENCRYPT_MODE, key);
			cipherText = cipher.doFinal(input);
	    	
			FileOutputStream fos = new FileOutputStream(file);
			fos.write(cipherText);
			fos.close();
		} catch(Exception e) {
			System.err.println("Failed to encrypt");
			System.err.println(e.getMessage());
			System.exit(1);
		}
    	
	}
	
	public static void symmetricDecrypt(String filename) {
		try {     
			File file = new File(filename);
			int ctLength = (int)file.length();
			byte[] cipherText = new byte[ctLength];
			FileInputStream fis = new FileInputStream(file);
			int b = fis.read();
			int i = 0;
			while(b != -1) {
				cipherText[i] = (byte)b;
				i++;
				b = fis.read();
			}
			fis.close();
			System.out.println("Read file");
	
			SecretKeySpec key = new SecretKeySpec(keyBytes, "DESede");
			Cipher cipher = Cipher.getInstance("DESede");
	
			byte[] plainText = new byte[ctLength];
			cipher.init(Cipher.DECRYPT_MODE, key);
			plainText = cipher.doFinal(cipherText);
	        
			filename += ".decrypted";
			file = new File(filename);
			FileOutputStream fos = new FileOutputStream(file);
			fos.write(plainText);
			fos.close();
		} catch(Exception e) {
			System.err.println("Failed to decrypt");
			System.err.println(e.getMessage());
			System.exit(1);
		}

	}
Thank you.