Retrofit+多线程下载

加载的网址方法

public class connect {    public static final String Url = "http://169.254.51.153:8080/";}

retrofit的封装

package com.example.myretrofit.api;import java.util.concurrent.TimeUnit;import okhttp3.OkHttpClient;import okhttp3.ResponseBody;import retrofit2.Retrofit;import retrofit2.adapter.rxjava.RxJavaCallAdapterFactory;import retrofit2.converter.gson.GsonConverterFactory;import retrofit2.http.Header;import retrofit2.http.POST;import retrofit2.http.Path;import retrofit2.http.Streaming;import rx.Observable;public interface HomeApi {    @Streaming    @POST("{fileName}")    Observable<ResponseBody> downloadFile(@Path("fileName") String fileName, @Header("Range") String range);    @Streaming    @POST("{fileName}")    Observable<ResponseBody> getFilelength(@Path("fileName") String fileName);    OkHttpClient client=new OkHttpClient.Builder()            .connectTimeout(5, TimeUnit.SECONDS)            .readTimeout(5,TimeUnit.SECONDS)            .build();    Retrofit RETROFIT=new Retrofit.Builder()            .client(client)            .addConverterFactory(GsonConverterFactory.create())            .addCallAdapterFactory(RxJavaCallAdapterFactory.create())            .baseUrl(connect.Url)            .build();    HomeApi requsetApi = RETROFIT.create(HomeApi.class);}

DownloadThread

package com.example.myretrofit.net;import android.util.Log;import com.example.myretrofit.api.HomeApi;import java.io.BufferedInputStream;import java.io.File;import java.io.IOException;import java.io.RandomAccessFile;import okhttp3.ResponseBody;import rx.Observer;import rx.schedulers.Schedulers;public class DownloadThread{    private String downloadUrl="";    private String path;    private int threadNum=5;    long length;    public DownloadThread(String downloadUrl, String path) {        this.downloadUrl = downloadUrl;        this.path = path;    }    public void show(){                HomeApi.requsetApi.getFilelength(downloadUrl)                        .observeOn(Schedulers.io())                        .subscribeOn(Schedulers.io())                        .subscribe(new Observer<ResponseBody>() {            @Override            public void onCompleted() {            }            @Override            public void onError(Throwable throwable) {                Log.i("-----onError-------", "onError: "+throwable.getMessage());            }            @Override            public void onNext(ResponseBody responseBody) {                length=responseBody.contentLength();                downoadTask(length);            }        });    }    public void downoadTask(Long length){        final File file=new File(path);        if(!file.exists()){            try {                file.createNewFile();            } catch (IOException e) {                e.printStackTrace();            }        }        DialogUrils.MAX_SIZE=length;        Log.i("------length-------", "downoadTask: "+length);        long blockSize=length/threadNum;        for (int i = 0; i < threadNum; i++) {            final long startposition=blockSize*i;            if(i==threadNum-1){                blockSize=length-blockSize*(threadNum-1);            }            String range="bytes="+startposition+"-"+(startposition+blockSize-1);            Log.i("------range-------", "downoadTask: "+range);           HomeApi.requsetApi.downloadFile(downloadUrl,range)                   .subscribeOn(Schedulers.io())                   .observeOn(Schedulers.io())                   .subscribe(new Observer<ResponseBody>() {                @Override                public void onCompleted() {                }                @Override                public void onError(Throwable throwable) {                    Log.i("-----error-----", "onResponse: "+throwable.getMessage());                }                @Override                public void onNext(ResponseBody responseBody) {                    try {                        Log.i("-----error-----", "onResponse: "+"进来了");                        BufferedInputStream bis=new BufferedInputStream(responseBody.byteStream());                        RandomAccessFile raf=new RandomAccessFile(file,"rwd");                        raf.seek(startposition);                        byte[] buff=new byte[1024*8];                        int len=0;                        while ((len=bis.read(buff))!=-1){                            raf.write(buff,0,len);                            if(DialogUrils.PROGRESS<0){                                DialogUrils.PROGRESS=0;                            }                            DialogUrils.PROGRESS+=len;                            Log.i(Thread.currentThread() + "-----len-----", "onResponse: "+ startposition + len);                        }                    } catch (Exception e) {                        e.printStackTrace();                    }                }            });        }    }}

DialogUrils

package com.example.myretrofit.net;import android.app.AlertDialog;import android.app.ProgressDialog;import android.content.Context;import android.content.DialogInterface;import android.os.AsyncTask;import android.os.SystemClock;public class DialogUrils {    public static long MAX_SIZE=0;    public static long PROGRESS=-2;    public static void showUpdateDialog(final Context context){        new AlertDialog.Builder(context)                .setTitle("更新吧")                .setNegativeButton("就不",null)                .setPositiveButton("好吧", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        DownloadThread downloadThread=new DownloadThread("马丁·路德·金：我有一个梦想.mp4",context.getCacheDir()+"/haha.mp4");                        downloadThread.show();                        showProgress(context);                    }                })                .show();    }    public static void showProgress(Context context){        final ProgressDialog pd=new ProgressDialog(context);        pd.setTitle("正在更新");        pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);        pd.setMax(100);        pd.show();        new AsyncTask<String,Integer,String>(){            @Override            protected String doInBackground(String... params) {                while (PROGRESS+1<MAX_SIZE){                    SystemClock.sleep(10);                    if(MAX_SIZE>0){                        publishProgress((int)(PROGRESS*100/MAX_SIZE));                    }                }                return null;            }            @Override            protected void onProgressUpdate(Integer... values) {                super.onProgressUpdate(values);                pd.setProgress(values[0]);            }        }.execute();    }}

MainActivity
一个是下载sd卡，一是从路径里直接取出来

package com.example.myretrofit;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.widget.VideoView;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);       // DialogUrils.showUpdateDialog(this);        show();    }    private void show() {        VideoView vv= (VideoView) findViewById(R.id.vv);        vv.setVideoPath(MainActivity.this.getCacheDir()+"/haha.mp4");        vv.start();    }}

<?xml version="1.0" encoding="utf-8"?><RelativeLayout    xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"    android:layout_height="match_parent" tools:context="com.example.myretrofit.MainActivity">    <VideoView        android:id="@+id/vv"        android:layout_width="400dp"        android:layout_height="300dp" /></RelativeLayout>