Why does my implementation of CBC mode only decrypt the first block correctly? [closed]

Question

I have the following code that uses a CBC mode to encrypt a text by dividing it to 3-elements block. But it only works correctly on the first block which is xored with the IV.

import java.util.ArrayList;

public class Encryption {
    static int[][] key ={{167,8,48},
        {54,107,25},
        {170,184,107}};
    static int[][] keyRevers ={{119,152,136},
        {184,235,231},
        {174,120,59}};

    //static int[] IV = {17,5,87};
    static ArrayList<Integer> IV = new ArrayList<Integer>();

    public Encryption(){
        IV.add(167);
        IV.add(8);
        IV.add(48);    
    }

    public static String enc(String input){
        ArrayList<ArrayList<Integer>> encryptedBlocks = new ArrayList<ArrayList<Integer>>();

        ArrayList<Integer> textValue = new ArrayList<Integer>();
        ArrayList<ArrayList<Integer>> blocks = new ArrayList<ArrayList<Integer>>();

        // get characters ----------------------
        for(int i =0; i<input.length();i++){
            textValue.add((int)input.charAt(i)); 
        }

        // create blocks------------------------
        int noOfBlocks = (int) Math.ceil(textValue.size()/3.0);
        for(int j =0; j<noOfBlocks;j++){
            blocks.add(new ArrayList<Integer>());
        }

        // add values to blocks-----------------
        int counter=0;

        for(int j =0; j<textValue.size();j++){
            if(j%3==0 && j!=0){
                counter ++;
            }
            blocks.get(counter).add(textValue.get(j));
        }    

        // CBC ----------------- (xoring)
        for(int k=0;k<blocks.size();k++){
            ArrayList<Integer> list =null;
            if(k==0)
            {
                list = encryptBlock(xor(blocks.get(k),IV));
            }else
            {
                list = encryptBlock(xor(blocks.get(k),encryptedBlocks.get(k-1)));
            }
            encryptedBlocks.add(list);
        }

        String val="";

        for(int k=0;k<encryptedBlocks.size();k++){
            for(int h=0;h<encryptedBlocks.get(k).size();h++){
                val += String.valueOf((char)(encryptedBlocks.get(k).get(h)+0));
            }
        }
        return val;    
    }

    public static String dec(String input){
        ArrayList<ArrayList<Integer>> decryptedBlocks = new ArrayList<ArrayList<Integer>>();

        ArrayList<Integer> textValue = new ArrayList<Integer>();
        ArrayList<ArrayList<Integer>> blocks = new ArrayList<ArrayList<Integer>>();

        for(int i =0; i<input.length();i++){
            textValue.add((int)input.charAt(i)); 
        }

        int noOfBlocks = (int) Math.ceil(textValue.size()/3.0);
        for(int j =0; j<noOfBlocks;j++){
            blocks.add(new ArrayList<Integer>());
        }

        int counter=0;

        for(int j =0; j<textValue.size();j++){
            if(j%3==0 && j!=0){
                counter ++;
            }    
            blocks.get(counter).add(textValue.get(j));
        }
        for(int k=0;k<blocks.size();k++){
            ArrayList<Integer> list = null;
            if(k==0)
            {
                list = xor(decryptBlock(blocks.get(k)),IV);
            }else
            {
                list = xor(decryptBlock(blocks.get(k)),decryptedBlocks.get(k-1));
            }    
            decryptedBlocks.add(list);
        }
        String val="";

        for(int k=0;k<decryptedBlocks.size();k++){
            for(int h=0;h<decryptedBlocks.get(k).size();h++){
                val += String.valueOf((char)(decryptedBlocks.get(k).get(h)+0));
            }
        }    
        return val;
    }

    public static ArrayList<Integer> decryptBlock(ArrayList<Integer> block){    
        ArrayList<Integer> list =  new ArrayList<Integer>();
        for(int x=0;x<block.size();x++){
            int no=0;

            for(int y=0;y<block.size();y++){
                no += keyRevers[x][y]*block.get(y);
            }
            list.add(no%256);
        }
        return list;
    }

    public static ArrayList<Integer> encryptBlock(ArrayList<Integer> block){
        ArrayList<Integer> list =  new ArrayList<Integer>();
        for(int x=0;x<block.size();x++){
            int no=0;

            for(int y=0;y<block.size();y++){
                no += key[x][y]*block.get(y);
            }    
            list.add((no%256));
        }
        return list;
    }

    public static ArrayList<Integer> xor(ArrayList<Integer> plainText,ArrayList<Integer> encrypted){
        ArrayList<Integer> xoredBlock = new ArrayList<Integer>();
        for(int i=0;i<plainText.size();i++){
            xoredBlock.add((plainText.get(i)^(encrypted.get(i))));
        }
        return xoredBlock;
    }
}

Answer 1

list = xor(decryptBlock(blocks.get(k)), decryptedBlocks.get(k-1));

You need to xor with the same thing you xored with during encryption: the previous block of the ciphertext, not the previous block of the plaintext.

list = xor(decryptBlock(blocks.get(k)), blocks.get(k-1));

Check the following illustration from wikipedia: