• 安卓基础干货(五)：安卓线程与数据上传下载的学习

    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）

    1. 导入xutils包

    2. 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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  • 原文地址：https://www.cnblogs.com/fanchcho/p/9233935.html
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