UVA - 12504 - Updating a Dictionary

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int cases = Integer.parseInt(br.readLine());
        StringBuffer sb = new StringBuffer("");
        for (int i = 0; i < cases; i++) {
            String dic1 = br.readLine();
            String dic2 = br.readLine();
            dic1 = dic1.substring(1, dic1.length() - 1);
            dic2 = dic2.substring(1, dic2.length() - 1);
            HashMap<String, String> hm = new HashMap<String, String>();
            ArrayList<String> add = new ArrayList<String>();
            ArrayList<String> sub = new ArrayList<String>();
            ArrayList<String> change = new ArrayList<String>();
            if (!dic1.equals("") && !dic2.equals("")) {
                String[] str = dic1.split(",");
                for (int j = 0; j < str.length; j++) {
                    String[] ans = str[j].split(":");
                    hm.put(ans[0], ans[1]);
                    sub.add(ans[0]);
                }
                str = dic2.split(",");
                for (int j = 0; j < str.length; j++) {
                    String[] ans = str[j].split(":");
                    if (hm.containsKey(ans[0])) {
                        sub.remove(ans[0]);
                        String val = hm.get(ans[0]);
                        if (!val.equals(ans[1])) {
                            change.add(ans[0]);
                        }
                    } else {
                        add.add(ans[0]);
                    }
                }
            }else if(dic1.equals("")&&!dic2.equals("")){
                 String[]str = dic2.split(",");
                 for (int j = 0; j < str.length; j++) {
                    String[] ans = str[j].split(":");
                    add.add(ans[0]);
                 }
            }else if(!dic1.equals("")&&dic2.equals("")){
                 String[]str = dic1.split(",");
                 for (int j = 0; j < str.length; j++) {
                    String[] ans = str[j].split(":");
                    sub.add(ans[0]);
                 }
            }
            if(!add.isEmpty()){
                Collections.sort(add);
            }
            if(!sub.isEmpty()){
                Collections.sort(sub);
            }
            if(!change.isEmpty()){
                Collections.sort(change);
            }
            boolean first = true, enterOnce = false, entered = false;
                while (!add.isEmpty()) {
                    if (first) {
                        sb.append("+");
                        first = false;
                    } else {
                        sb.append(",");
                    }
                    sb.append(add.remove(0));
                    enterOnce = true;
                    entered = true;
                }
                if (entered) {
                    sb.append("\n");
                }
                entered = false;
                first = true;
                while (!sub.isEmpty()) {
                    if (first) {
                        sb.append("-");
                        first = false;
                    } else {
                        sb.append(",");
                    }
                    sb.append(sub.remove(0));
                    enterOnce = true;
                    entered = true;
                }
                if (entered) {
                    sb.append("\n");
                }
                first = true;
                entered = false;
                while (!change.isEmpty()) {
                    if (first) {
                        sb.append("*");
                        first = false;
                    } else {
                        sb.append(",");
                    }
                    sb.append(change.remove(0));
                    enterOnce = true;
                    entered = true;
                }
                if (entered) {
                    sb.append("\n");
                }
                if (!enterOnce) {
                    sb.append("No changes\n");
                }
                sb.append("\n");
        }
        System.out.print(sb);
    }
}