My code review

源代码如下

package com.example.asynctask;

import android.app.ProgressDialog;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {
     Button button;
     ImageView imageView;
     ProgressDialog progressDialog;
     String IMAGE_PATH="http://image.baidu.com/search/redirect?tn=redirect&word=j&juid=51AEAB&sign=cibzwikaba&url=http%3A%2F%2Flife.northnews.cn%2F2015%2F0515%2F1927051_20.shtml&objurl=http%3A%2F%2Fupload.northnews.cn%2F2015%2F0515%2F1431655212431.jpg";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button = (Button) findViewById(R.id.button);
        imageView = (ImageView) findViewById(R.id.image);
        progressDialog = new ProgressDialog(MainActivity.this);
        progressDialog.setTitle("提示信息");
        progressDialog.setCancelable(false);
        progressDialog.setMessage("正在下载中，请稍后。。。");
        progressDialog.setProgressStyle(progressDialog.STYLE_HORIZONTAL);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                new MyAsyncTask().execute(IMAGE_PATH); }
        })
;
    }
    public class MyAsyncTask extends AsyncTask<String,Integer,byte[]>{
        @Override
        protected void onPreExecute() {super.onPreExecute();
            progressDialog.show(); }

        @Override
        protected byte[] doInBackground(String... strings) {
            byte[] image = new byte[]{};
            HttpURLConnection connection = null;
            InputStream inputStream = null;
            ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
            Log.i("test","    =====    ");

            try {
                URL url = new URL(strings[0]);
                connection = (HttpURLConnection) url.openConnection();
                if (connection.getResponseCode()==200){
                    file_length = connection.getContentLength();
                    long totle_length = 0;
                    int length = 0;
                    byte[] data = new byte[1024];
                    inputStream = connection.getInputStream();
                    while (-1 !=(length = inputStream.read(data))){
                        totle_length += length;
                        byteArrayOutputStream.write(data,0,length);
                        int progress = ((int)(totle_length*100/(float)file_length));
                        publishProgress(progress);

                        try {
                            Thread.sleep(1000);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                    Log.i("test","-----");
                    image = byteArrayOutputStream.toByteArray();
                    inputStream.close();
                    byteArrayOutputStream.close();
                }

            } catch (MalformedURLException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                connection.disconnect();
            }return image;
        }

        @Override
        protected void onProgressUpdate(Integer... values) {
            super.onProgressUpdate(values);
            progressDialog.setProgress(values[0]);}

        @Override
        protected void onPostExecute(byte[] bytes) {
            super.onPostExecute(bytes);
            Bitmap bitmap = BitmapFactory.decodeByteArray(bytes,0,bytes.length);
            imageView.setImageBitmap(bitmap);
            progressDialog.dismiss();
        }
    }
}

存在的问题：

1.不是所有代码都简单易懂 ，代码的变量名没有注意到，有的可能没加

2.不太符合编程规范。大括号的位置有的随意乱放，只要没有出现错误就行。基本没有注释   

3.可能存在多余的代码  

4.代码没有尽可能的模块化