安卓基础干货(五)：安卓线程与数据上传下载的学习

緣來

发布于 2018-09-18 17:53:19

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代码可运行

使用POST方式提交数据时的中文乱码解决方法（重点）

解决办法：使用客户端和服务器两边的字符集编码保持一致。 UTF-8，

使用GET方式提交数据的中文乱码的解决方法

使用URLEncoder.encode(name,"UTF-8")进行url编码：
String path = "http://192.168.22.136:8080/web/servlet/LoginServlet?username="+URLEncoder.encode(name,"UTF-8")+"&password="+URLEncoder.encode(pwd,"UTF-8");

使用httpclient提交数据（重点）

apache httpClient 轻量级的浏览器：

使用GET方式数据步骤： 1、创建一个浏览器： 2、输入一个网址： 3、敲回车

模块代码：

package com.itheima.qqlogin;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import com.itheima.htmlview.utils.StreamTools;

import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    private EditText et_name;
    private EditText et_pwd;

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

        et_name = (EditText) findViewById(R.id.et_name);
        et_pwd = (EditText) findViewById(R.id.et_pwd);

    }

    public void login(View view){
        final String name = et_qq.getText().toString().trim();

        final String pwd = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)){
            Toast.makeText(this, "qq和密码不能空", 0).show();
            return;
        }else {
            new Thread() {

                public void run() {

                    try {
                        String path = "http://192.168.22.136:8080/web/servlet/LoginServlet?username="+URLEncoder.encode(name,"UTF-8")+"&password="+URLEncoder.encode(pwd,"UTF-8");                      //1、创建一个浏览器：
                        HttpClient client = new DefaultHttpClient();
                        //2、输入一个网址：
                        HttpGet httpGet = new HttpGet(path);
                        //3、敲回车
                        HttpResponse response = client.execute(httpGet);
                        //获取服务器端返回的响应码（状态码）
                        int code =  response.getStatusLine().getStatusCode();
                        //int code = conn.getResponseCode();
                        if(code == 200){
                        //4、解析服务器返回的二进制数据，解析成一个字符串
                            //InputStream is = conn.getInputStream();
                            //获取服务器返回的二进制数据流
                            InputStream is = response.getEntity().getContent();

                            String result = StreamTools.readStream(is);
                            System.out.println("---------"+ result);
                         }

                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                };
            }.start();
        }
    }    
}

使用post方式向服务器端提交数据 1、创建一个浏览器： 2、输入一个网址： 3、敲回车模版代码：

package com.itheima.qqlogin;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

import com.itheima.htmlview.utils.StreamTools;

public class MainActivity extends Activity {

    private EditText et_qq;

    private EditText et_pwd;

    private Handler handler = new Handler(){
        public void handleMessage(android.os.Message msg) {

            String result = (String) msg.obj;

            Toast.makeText(MainActivity.this, result, 0).show();
        };
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        et_qq = (EditText) findViewById(R.id.et_qq);

        et_pwd = (EditText) findViewById(R.id.et_pwd);

    }

    public void login(View view){
        final String name = et_qq.getText().toString().trim();

        final String pwd = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)){
            Toast.makeText(this, "qq和密码不能空", 0).show();
            return;
        }else{
            new Thread(){

                public void run() {

                    try {
                        String path = "http://192.168.1.196:8080/web/servlet/LoginServlet";
                        //String data = "username="+name+"&password="+pwd;
                        String data = "username="+URLEncoder.encode(name,"UTF-8")+"&password="+URLEncoder.encode(pwd,"UTF-8");

                        //1、创建一个浏览器：
                        HttpClient client = new DefaultHttpClient();
                        //2、输入一个网址：
                        HttpPost httpPost = new HttpPost(path);
                        List<BasicNameValuePair> parameters = new ArrayList<BasicNameValuePair>();

                        BasicNameValuePair p1 = new BasicNameValuePair("username", name);

                        BasicNameValuePair p2 = new BasicNameValuePair("password", pwd);
                        parameters.add(p1);
                        parameters.add(p2);
                        //默认使用iso-8859-1编码，需要指定UTF-8
                        UrlEncodedFormEntity entity = new UrlEncodedFormEntity(parameters,"UTF-8");

                        //3、敲回车
                        //设置提交的数据
                        httpPost.setEntity(entity);
                        HttpResponse  response = client.execute(httpPost);

                        //4、服务器返回数据
                        //（1）判断状态码：200 ok，404 没有找到资源、503、509 服务器端错误
                        int code =  response.getStatusLine().getStatusCode();
                        //int code = conn.getResponseCode();
                        if(code == 200){
                            //(2）解析服务器返回的二进制数据，解析成一个字符串
                            InputStream is = response.getEntity().getContent();   
                            String result = StreamTools.readStream(is);
                            System.out.println("---------"+ result); 
                            Message msg = Message.obtain();
                            msg.obj = result;
                            handler.sendMessage(msg);
                        }   
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                };
            }.start();
        }
    }
}

使用Aynchttpclient向服务器端提交数据（重点）

1、创建一个浏览器：

2、输入一个网址：

3、敲回车

使用GET方式向服务器端提交数据

package com.itheima.qqlogin;

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;

import org.apache.http.Header;

import com.itheima.htmlview.utils.StreamTools;
import com.loopj.android.http.AsyncHttpClient;
import com.loopj.android.http.AsyncHttpResponseHandler;

import android.app.Activity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    private EditText et_name;

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

        et_qq = (EditText) findViewById(R.id.et_qq);

        et_pwd = (EditText) findViewById(R.id.et_pwd);

    }

    public void login(View view){
        final String name = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)){
            Toast.makeText(this, "qq和密码不能空", 0).show();
            return;
        }else{  
            try {
                String path = "http://192.168.1.103:8080/web/servlet/LoginServlet?username="+URLEncoder.encode(name,"UTF-8")+"&password="+URLEncoder.encode(pwd,"UTF-8");
                //1、创建一个浏览器： 
                AsyncHttpClient client = new AsyncHttpClient();
                //2、输入网址，调用get方式向服务器发送请求：
                client.get(path, new AsyncHttpResponseHandler() {

                    /*
                     * 请求成功，服务器端正常响应 响应码200
                     * statusCode 响应码200ok，404没有找到资源，503服务器内部错误, Header[] headers 响应头信息, byte[] responseBody 服务器返回的数据
                     */
                    @Override
                    public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                        Toast.makeText(MainActivity.this, new String(responseBody), 0).show();
                    }   

                     /*
                     * 请求成功，服务器端正常响应 响应码200
                     * int statusCode, Header[] headers, byte[] responseBody, Throwable error
                     * statusCode 响应码200ok，404没有找到资源，503服务器内部错误, Header[] headers 响应头信息, byte[] responseBody 服务器返回的数据
                     * Throwable error 服务器端返回的异常
                     */
                    @Override
                    public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable arg3) {
                        Toast.makeText(MainActivity.this, new String(responseBody), 0).show();
                    }
                });
            } catch (Exception e) {
                e.printStackTrace();
            }
        };
    }
}

使用POST方式向服务器端提交数据

package com.itheima.qqlogin;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;

import org.apache.http.Header;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

import com.itheima.htmlview.utils.StreamTools;
import com.loopj.android.http.AsyncHttpClient;
import com.loopj.android.http.AsyncHttpResponseHandler;
import com.loopj.android.http.RequestParams;

public class MainActivity extends Activity {

    private EditText et_qq;

    private EditText et_pwd;

    private Handler handler = new Handler(){
        public void handleMessage(android.os.Message msg) {

            String result = (String) msg.obj;

            Toast.makeText(MainActivity.this, result, 0).show();
        };
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        et_qq = (EditText) findViewById(R.id.et_qq);

        et_pwd = (EditText) findViewById(R.id.et_pwd);

    }

    public void login(View view){
        final String name = et_qq.getText().toString().trim();

        final String pwd = et_pwd.getText().toString().trim();

        if(TextUtils.isEmpty(name) || TextUtils.isEmpty(pwd)){
            Toast.makeText(this, "qq和密码不能空", 0).show();
            return;
        }else{
            try {
                String path = "http://192.168.22.136:8080/web/servlet/LoginServlet";
                //String data = "username="+name+"&password="+pwd;

                //String data = "username="+URLEncoder.encode(name,"UTF-8")+"&password="+URLEncoder.encode(pwd,"UTF-8");
                //1、创建一个浏览器：
                AsyncHttpClient client = new AsyncHttpClient(); 
                //2、输入一个网址,敲回车：
                RequestParams params = new RequestParams();
                params.put("username", name);
                params.put("password", pwd);

                client.post(path, params, new AsyncHttpResponseHandler() {

                    @Override
                    public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                        Toast.makeText(MainActivity.this, new String(responseBody), 0).show();

                    }

                    @Override
                    public void onFailure(int statusCode, Header[] headers, byte[] responseBody, Throwable e) {
                        Toast.makeText(MainActivity.this, new String("服务器端返回数据失败"), 0).show();
                    }
                });
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }     
}

多线程下载的原理

javase实现多线程

步骤：

1、在客户端创建一个与服务器端大小一样的空白文件
2、设置子线程的个数
3、计算每个子线程下载的数据块大小和下载起始位置、结束位置
4、创建子线程开始下载数据
5、得到每个子线程都下载完成的标记

代码： MultiThreadDownLoader.java:

import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

public class MultiThreadDownLoader {

    //2、使用的子线程的个数
    private static int threadCount =3;

    /**
     * @param args
     */
    public static void main(String[] args) {
        try {
            String path = "http://192.168.22.136:8080/sogou.exe";
            URL url = new URL(path);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(3000);

            int code = conn.getResponseCode();
            if(code == 200){
                int length =    conn.getContentLength();
                //1、在客户端创建一个与服务端文件一样大小的文件
                RandomAccessFile file = new RandomAccessFile("temp.exe", "rw");
                file.setLength(length);
                //3、每个子线程下载数据块 ,下载的起始位置和结束位置
                int blockSize = length/threadCount;

                // threadId * blockSize  ---- （threadId+1）* blockSize -1
                for(int threadId =0; threadId < threadCount; threadId++){
                    //下载的起始位置和结束位置
                    int startIndex = threadId * blockSize;
                    int endIndex = 0;

                    if(threadId != (threadCount -1)){
                         endIndex = (threadId + 1) * blockSize - 1;
                    }else{
                        endIndex = length-1;
                    }
                    //开启子线程下载数据
                    new ThreadDownLoader(path, startIndex, endIndex, threadId, threadCount).start();
                }
            }else{
                //抛出异常
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

ThreadDownLoader.java:

import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;


public class ThreadDownLoader extends Thread {

    private String path;
    private int startIndex;
    private int endIndex;
    private int threadId;
    private int threadCount;
    //正在运行的线程个数
    private static  int runningThreadCount = 3; 
    ThreadDownLoader(String path,int startIndex,int endIndex,int threadId,int threadCount){
        this.path = path;
        this.startIndex = startIndex;
        this.endIndex = endIndex;
        this.threadId = threadId;
        this.threadCount = threadCount; 
    }

    @Override
    public void run() {
        downLoad(path,startIndex,endIndex,threadId,threadCount);
    }

    public void downLoad(String path,int startIndex,int endIndex,int threadId,int threadCount) {
        try {
            URL url = new URL(path);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();

            conn.setRequestMethod("GET");
            conn.setConnectTimeout(3000);
            //设置子线程请求数据的范围
            conn.setRequestProperty("Range", "bytes="+startIndex+"-"+endIndex);
            int code = conn.getResponseCode();
            if(code == 206){//请求部分数据

                InputStream is = conn.getInputStream();
                RandomAccessFile file = new RandomAccessFile("temp.exe","rw");
                //指定从哪个位置开始写数据
                file.seek(startIndex);

                byte[] buffer = new byte[1024];
                int len = -1;
                while((len = is.read(buffer)) != -1){
                    file.write(buffer, 0, len);
                }

                file.close();
                System.out.println("线程"+threadId+"下载完成...............");
                synchronized (ThreadDownLoader.this) {
                    runningThreadCount--;
                    if(runningThreadCount == 0){
                        System.out.println("文件下载完成...............");
                    }
                }
            }
        } catch (Exception e) {
             System.out.println("线程"+threadId+"下载失败...............");
            e.printStackTrace();
        }  
    }   
}

断点续传下载

1、实时记录线程下载的位置；

2、接上一次下载的位置继续下载；

代码：

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;
import java.nio.channels.ReadableByteChannel;

public class ThreadDownLoader extends Thread {

    private String path;
    private int startIndex;
    private int endIndex;
    private int threadId;
    private int threadCount;
    //正在运行的线程个数
    private static int runningThreadCount = 3; 
    ThreadDownLoader(String path,int startIndex,int endIndex,int threadId,int threadCount){
        this.path = path;
        this.startIndex = startIndex;
        this.endIndex = endIndex;
        this.threadId = threadId;
        this.threadCount = threadCount;

    }

    @Override
    public void run() {
        downLoad(path,startIndex,endIndex,threadId,threadCount);
    }

    public void downLoad(String path,int startIndex,int endIndex,int threadId,int threadCount){
        try {
            URL url = new URL(path);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod("GET");
            conn.setConnectTimeout(3000);

            //获取上一次下载的位置，接着下载
            File threadFile = new File(threadId+".txt");
            if (threadFile.exists() && threadFile.length() > 0){
                FileReader fr = new FileReader(threadFile);
                BufferedReader br = new BufferedReader(fr);
                String position = br.readLine();
                //设置子线程请求数据的范围
                conn.setRequestProperty("Range", "bytes="+position+"-"+endIndex);
                startIndex = Integer.valueOf(position);
            }else{
                //设置子线程请求数据的范围
                conn.setRequestProperty("Range", "bytes="+startIndex+"-"+endIndex);
            }


            int code = conn.getResponseCode();
            if(code == 206){//请求部分数据

                InputStream is = conn.getInputStream();
                RandomAccessFile file = new RandomAccessFile("temp.exe","rw");
                //指定从哪个位置开始写数据
                file.seek(startIndex);

                byte[] buffer = new byte[1024*1024];
                int len = -1;
                int total = 0;
                while((len = is.read(buffer)) != -1){
                    file.write(buffer, 0, len);
                    total = total + len;
                    int currentPosition = startIndex + total;
                    //能够即时的把数据写到数据
                    RandomAccessFile f = new RandomAccessFile(threadId+".txt", "rwd");
                    f.write((currentPosition+"").getBytes());
                    f.close();  
                }

                file.close();
                System.out.println("线程"+threadId+"下载完成...............");
                synchronized (ThreadDownLoader.this) {
                    runningThreadCount--;
                    if(runningThreadCount == 0){
                        System.out.println("文件下载完成...............");
                    }
                }
            }
        } catch (Exception e) {
            System.out.println("线程"+threadId+"下载失败...............");
            e.printStackTrace();
        }
    }
}

多线程下载移植到Android项目上（重点）

1、设置布局文件：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >

<EditText
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="请输入下载的文件网络地址"
    android:id="@+id/et_path" />

<EditText
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:hint="开启几个子线程加速下载"
    android:text="3"
    android:id="@+id/et_threadCount" />

<Button 
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="下载"
    android:onClick="downLoad"
    />

</LinearLayout>

2、修改代码：

MainActivity.java:

package com.itheima.multithreaddownload;

import java.io.RandomAccessFile;
import java.net.HttpURLConnection;
import java.net.URL;

import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {

    private EditText et_path;
    private EditText et_threadCount;

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

        et_path = (EditText) findViewById(R.id.et_path);
        et_threadCount = (EditText) findViewById(R.id.et_threadCount);
    }

    public void downLoad(View view){

        final String path = et_path.getText().toString().trim();
        String threadCountStr = et_threadCount.getText().toString().trim();

        if(TextUtils.isEmpty(path) || TextUtils.isEmpty(threadCountStr)){
            Toast.makeText(this, "下载地址或线程个数不能为空", 0).show();
            return;
        } else {
            final int threadCount = Integer.valueOf(threadCountStr);

            new Thread(){
                public void run() {
                    try {
                        //String path = "http://192.168.22.136:8080/sogou.exe";
                        URL url = new URL(path);
                        HttpURLConnection conn = (HttpURLConnection) url.openConnection();

                        conn.setRequestMethod("GET");
                        conn.setConnectTimeout(3000);
                        int code = conn.getResponseCode();
                        if(code == 200){
                            int length =    conn.getContentLength();
                            //1、在客户端创建一个与服务端文件一样大小的文件
                            RandomAccessFile file = new RandomAccessFile(Environment.getExternalStorageDirectory()+"/temp.exe", "rw");
                            file.setLength(length);
                            //3、每个子线程下载数据块 ,下载的起始位置和结束位置
                            int blockSize = length/threadCount;

                            // threadId * blockSize  ---- （threadId+1）* blockSize -1
                            for(int threadId =0; threadId < threadCount; threadId++){
                                //下载的起始位置和结束位置
                                int startIndex = threadId * blockSize;
                                int endIndex = 0;

                                if(threadId != (threadCount -1)){
                                     endIndex = (threadId + 1) * blockSize - 1;
                                }else{
                                    endIndex = length-1;
                                }   
                                //开启子线程下载数据
                                new ThreadDownLoader(path, startIndex, endIndex, threadId, threadCount).start();
                            }
                        }else{
                            //抛出异常
                        }
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                };
            }.start();
        }
    }
}

使用xutils实现多线程下载（重点）

导入xutils包
初始化httputils对象

HttpUtils http = new HttpUtils();
 /**
 * 2 进行下载 
 * url 下载的路径
 * target 存放目标地址 
 * autoResume  是否支持断点续传下载 
 */
http.download(path, "/mnt/sdcard/feiq.exe", true, new RequestCallBack<File>() {

    //下载成功的回调
    @Override
    public void onSuccess(ResponseInfo<File> responseInfo) {
        Toast.makeText(getApplicationContext(), "下载成功", 0).show();

    }

    //下载失败的回调
    @Override
    public void onFailure(HttpException error, String msg) {
    }
    //当前进度 
    @Override
    public void onLoading(long total, long current, boolean isUploading) {

        pb.setMax((int) total); //设置进度条的最大值
        pb.setProgress((int) current);

        super.onLoading(total, current, isUploading);
    }

});

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