//進(jìn)行流的讀寫     byte[] buffer = new byte[1024 * 8];     //創(chuàng)建一個(gè)寫到內(nèi)存的字節(jié)數(shù)組輸出流     ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();     int len;     while ((len = inputStream.read(buffer)) != -1) {       byteArrayOutputStream.write(buffer,0,len);       byteArrayOutputStream.flush();//不斷的刷新緩存     }     byteArrayOutputStream.close();//進(jìn)行關(guān)閉流通道     result = byteArrayOutputStream.toString();//將寫入的字節(jié)流轉(zhuǎn)化為字符串

     //1.創(chuàng)建一個(gè)Url對象       URL url = new URL(url_str);     //2.獲取一個(gè)UrlConnection對象       HttpURLConnection connection = (HttpURLConnection)url.openConnection();     //3.為UrlConnection對象設(shè)置一些請求的參數(shù),請求方式，連接的超時(shí)時(shí)間        connection.setRequestMethod("GET");//設(shè)置請求方式       connection.setConnectTimeout(1000*10);//設(shè)置超時(shí)時(shí)間     //4.在獲取url請求的數(shù)據(jù)前需要判斷響應(yīng)碼，200 ：成功,206:訪問部分?jǐn)?shù)據(jù)成功  300：跳轉(zhuǎn)或重定向 400：錯(cuò)誤 500：服務(wù)器異常       int code = connection.getResponseCode();       if(code == 200){     //5.獲取有效數(shù)據(jù)，并將獲取的流數(shù)據(jù)解析成String         InputStream inputStream = connection.getInputStream();         String result = StreamUtils.streamToString(inputStream);

  1.主線程中創(chuàng)建一個(gè)Handler    private Handler handler = new Handler(){        public void handleMessage(android.os.Message msg) {        };    };    2.重寫handler的handlermessage方法    3.子線程中創(chuàng)建一個(gè)Message對象，將獲取的數(shù)據(jù)綁定給msg        Message msg = new Message();        //另一種方式：Message msg = Messge.obtain;        msg.obj = result;    4.主線程中的handler對象在子線程中將message發(fā)送給主線程        handler.sendMessage(msg);    5.主線程中handlermessage方法接受子線程發(fā)來的數(shù)據(jù)，就可以做更新UI的操作。

public class MainActivity extends AppCompatActivity {  private EditText et_url;  private Button btn_looksource;  private TextView tv_sourceshow;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    //1，找到控件ID    et_url = (EditText)findViewById(R.id.ev_url);    btn_looksource = (Button)findViewById(R.id.btn_looksource);    tv_sourceshow = (TextView)findViewById(R.id.source_show);    //2，設(shè)置點(diǎn)擊事件    btn_looksource.setOnClickListener(new View.OnClickListener() {      @Override      public void onClick(View v) {        try {          //3，獲取URL地址          final String url_str = et_url.getText().toString().trim();          //String results ="";          //3.1進(jìn)行判斷URL是否為空          if (TextUtils.isEmpty(url_str)) {            Toast.makeText(MainActivity.this, "url地址不能為空的", Toast.LENGTH_SHORT).show();            return;          }          System.out.println("oclick方法線程："+Thread.currentThread().getName());          //創(chuàng)建子線程對象          new Thread(new Runnable() {            @Override            public void run() {            try {              System.out.println("oclick方法runnable線程："+Thread.currentThread().getName());              //4，請求URL地址              //4.1創(chuàng)建一個(gè)URL對象              URL url = new URL(url_str);              //4.2獲取URLConnection對象              HttpURLConnection connection = (HttpURLConnection) url.openConnection();              //4.3位URLconnection設(shè)置請求參數(shù)              connection.setRequestMethod("GET");              connection.setConnectTimeout(5 * 1000);              //4.4獲取請求響應(yīng)碼并進(jìn)行判斷              int code = connection.getResponseCode();              if (code == 200) {                //4.5獲取數(shù)據(jù)并且解析成字符串                InputStream inputStream = connection.getInputStream();                //4.6進(jìn)行獲取string數(shù)據(jù)讀出來的                String results = StreamUtils.streanTosting(inputStream);                //5,將數(shù)據(jù)顯示到TExtview 上                //tv_sourceshow.setText(results);                //☆☆☆3.子線中創(chuàng)建一個(gè)Message對象，為了攜帶子線程中獲取的數(shù)據(jù)給主線程。                //Message msg = new Message();                //msg.obj = result;//將獲取的數(shù)據(jù)封裝到msg中。                //☆☆☆4.使用handler對象將message發(fā)送到主線程。                //handler.sendMessage(msg);                Message msg = new Message();                msg.obj = results;                handler.sendMessage(msg);              }            }catch (Exception e) {              e.printStackTrace();            }          }          }).start();        }catch (Exception e) {          e.printStackTrace();        }      }    });  }  //☆☆☆1.在主線程中創(chuàng)建一個(gè)Handler對象  private Handler handler = new Handler(){    //☆☆☆2.重寫handler的handlermessage方法,用來接收子線程中發(fā)來的消息    public void handleMessage(android.os.Message msg) {      //☆☆☆5.接收子線程發(fā)送的數(shù)據(jù)，處理數(shù)據(jù)。      String result = (String) msg.obj;      //☆☆☆6.當(dāng)前方法屬于主線程可以做UI的更新      //五.獲取服務(wù)器返回的內(nèi)容，顯示到textview上      tv_sourceshow.setText(result);    };  };}

public class StreamUtils {  public static String streanTosting(InputStream inputStream){    String result = "";//保存字符串    try {      //進(jìn)行流的讀寫      byte[] buffer = new byte[1024 * 8];      //創(chuàng)建一個(gè)寫到內(nèi)存的字節(jié)數(shù)組輸出流      ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();      int len;      while ((len = inputStream.read(buffer)) != -1) {        byteArrayOutputStream.write(buffer,0,len);        byteArrayOutputStream.flush();//不斷的刷新緩存      }      byteArrayOutputStream.close();//進(jìn)行關(guān)閉流通道      result = byteArrayOutputStream.toString();//將寫入的字節(jié)流轉(zhuǎn)化為字符串    }catch (Exception e){      e.printStackTrace();    }    return result;  }}