Call Log / Oorya

//*********************MAIN ACTIVITY
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity
{

    EditText owner, lineNumber, lastPay;
    String lastPayStr;
    UtlFile utlFile;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        owner=(EditText)findViewById(R.id.owner);
        lineNumber=(EditText)findViewById(R.id.lineNumber);
        lastPay=(EditText)findViewById(R.id.lastPay);
        utlFile=new UtlFile(this);

    }

    public void btnAddData(View view)
    {
        lastPayStr=lastPay.getText().toString();

        if(!lineNumber.getText().toString().matches("((0[57]|[//+]?[1-9]{3}[57])([0-9]{8}))|(([0][23489]|[//+]?[1-9]{3}[23489])([0-9]{7}))"))
        {
            Toast.makeText(MainActivity.this, "Please type phone number", Toast.LENGTH_SHORT).show();
            return;
        }
        if(!lastPayStr.matches("[0-9]+"))
        {
            Toast.makeText(MainActivity.this, "Please type numbers", Toast.LENGTH_SHORT).show();
            return;
        }
        if(lineNumber.getText().toString().indexOf("050")>=0)
        {
            int newLastPay=Integer.parseInt(lastPay.getText().toString())*2;
            lastPayStr=newLastPay+"";
        }
        utlFile.writer(owner.getText().toString(),lineNumber.getText().toString(), lastPayStr);

        owner.setText("");
        lineNumber.setText("");
        lastPay.setText("");
    }

    public void btnDisplay(View view)
    {
        utlFile.reader();

        Intent displayIntent = new Intent(this, DisplayActivity.class);
        this.startActivity(displayIntent);
    }

    public void btnClear(View view)
    {
        utlFile.delete();
    }
}

//***************************DISPLAY ACTIVITY
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.TextView;

public class DisplayActivity extends AppCompatActivity
{
    private TextView txt, sumPay, sumCall;
    private ListView myListV;
    private Adapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_display);
        setPointer();

        myListV=(ListView)findViewById(R.id.myListV);

        adapter=new Adapter(this);
        myListV.setAdapter(adapter);
        sumPay.setText("Sum pay: "+UtlFile.getSumPay()+"");
        sumCall.setText("Most calls: "+UtlFile.getSumCall());
    }

    private void setPointer()
    {
        txt=(TextView)findViewById(R.id.text);
        sumPay=(TextView)findViewById(R.id.sumPay);
        sumCall=(TextView)findViewById(R.id.sumCall);

        txt.setText("Call Logs");
    }
}

//****************************UTL FILE
import android.content.Context;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

public class UtlFile
{
    private static final String  MY_FILE ="call_list.txt";
    private static final int READ_BLOCK_SIZE = 100;
    public  Context context;
    private FileOutputStream fileos;
    private OutputStreamWriter oswFile;
    private FileInputStream fileIS;
    private InputStreamReader isrFile;

    public static String s="";
    private static String tempLog;

    public String owner;
    public String linenumber;
    public int lastPay;

    public static ArrayList<UtlFile> myLogList =  new ArrayList<UtlFile>();



    public UtlFile(String owner, String linenumber, int lastPay)
    {
        this.owner=owner;
        this.linenumber=linenumber;
        this.lastPay=lastPay;
    }

    public UtlFile(Context context)
    {
        this.context=context;
    }


    public void writer(String owner, String linenumber, String lastPay)
    {
        try
        {
            fileos=context.openFileOutput(MY_FILE, context.MODE_PRIVATE);
            oswFile=new OutputStreamWriter(fileos);
            tempLog+=owner+","+linenumber+","+lastPay+",";
            oswFile.write(tempLog);
            oswFile.close();

        }catch (FileNotFoundException e) {
            e.printStackTrace();
        }catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void delete()
    {
        try {
            tempLog="";
            fileos=context.openFileOutput(MY_FILE, context.MODE_PRIVATE);
            oswFile=new OutputStreamWriter(fileos);
            oswFile.write("");

            oswFile.close();

            myLogList.clear();

        } catch (IOException e) {
            e.printStackTrace();
        }
    }


    public void reader()
    {
        try {
            myLogList.clear();
            fileIS= context.openFileInput(MY_FILE);  //pointer for reading the file
            isrFile = new InputStreamReader(fileIS); //create a reader (inputStreamReader)

            char[] inputBuffer = new char[READ_BLOCK_SIZE]; //size of buffer to read
            int charRead; // indicate if we have still data to read.....
            while ((charRead=isrFile.read(inputBuffer))>0)  //if we have still data to read
            {
                String readString=String.copyValueOf(inputBuffer,0,charRead); //we put into string variable the entire char read array
                s+=readString; //add read string to our string

                inputBuffer = new char[READ_BLOCK_SIZE]; //allocate new buffer to read
            }
            isrFile.close(); //close the connection to the file

        }catch (FileNotFoundException e) {
            e.printStackTrace();
        }catch (IOException e) {
            e.printStackTrace();
        }
    }

    public ArrayList<UtlFile> getLog()
    {
        int temp=1,temp1=2;
        myLogList.clear();
        String[] logArr = s.split(",");
        if(!s.equals("")) {
            myLogList.clear();
            for (int counter = 0; counter < logArr.length; counter += 3) {
                myLogList.add(new UtlFile(logArr[counter], logArr[temp], Integer.parseInt(logArr[temp1])));
                temp += 3;
                temp1 += 3;
            }
        }
        s="";

        return myLogList;
    }


    public static int getSumPay()
    {
        int sumPay=0;

        for(UtlFile pay:myLogList)
        {
            sumPay+=pay.lastPay;
        }
        return sumPay;
    }

    public static String getSumCall()
    {

        String sumCall="";

        Map<String,Integer> map = new HashMap<String, Integer>();
        for(int i=0;i<myLogList.size();i++){
            Integer count = map.get(myLogList.get(i).linenumber);
            map.put(myLogList.get(i).linenumber, count==null?1:count+1);//auto boxing and count
        }

        ArrayList<Integer> myInt =  new ArrayList<>();

        for(Map.Entry<String,?> log:map.entrySet())
        {
            myInt.add((Integer)log.getValue());
        }

        Collections.sort(myInt);

        for(Map.Entry<String,?> log:map.entrySet())
        {
            if(log.getValue()==myInt.get(myInt.size()-1))
            {
                sumCall+=log.getKey()+", ";
            }
        }

        return sumCall;
    }

}


//************************************ADAPTER
import android.content.Context;
import android.graphics.Color;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.util.ArrayList;


public class Adapter extends BaseAdapter {

    private Context context;
    private UtlFile utlfile;
    static ArrayList<UtlFile> myLogList;


    public Adapter(Context context)
    {
        this.context=context;

        utlfile = new UtlFile(context);
        myLogList=utlfile.getLog();

    }
    @Override
    public int getCount() {
        return myLogList.size();
    }

    @Override
    public Object getItem(int i) {
        return null;
    }

    @Override
    public long getItemId(int i) {
        return 0;
    }

    @Override
    public View getView(int i, View view, ViewGroup viewGroup)
    {
        LinearLayout mylayout=new LinearLayout(context);
        mylayout.setOrientation(LinearLayout.HORIZONTAL);
        mylayout.setBackgroundColor(Color.CYAN);

        TextView txt=new TextView(context);
        txt.setTextSize(30);

        txt.setText("Owner: "+myLogList.get(i).owner+"\n"
                +"Line number: "+myLogList.get(i).linenumber+"\n"
                +"Last pay: "+myLogList.get(i).lastPay);

        mylayout.addView(txt);
        return mylayout;
    }
}