http请求(一) 工具

  1 
  2 import java.io.ByteArrayOutputStream;
  3 import java.io.DataOutputStream;
  4 import java.io.InputStream;
  5 import java.net.HttpURLConnection;
  6 import java.net.URL;
  7 import java.net.URLEncoder;
  8 import java.util.Map;
  9 import android.util.Log;
 10 
 11 public class NetUtil {
 12 
 13     private static final String TAG = "NetUtil";
 14     private static final int RESPONSE_OK = 200;
 15     
 16     public static InputStream sendPostRequest(String urlPath,
 17             Map<String, String> params, String encoding) throws Exception {
 18         // String param = "method=save&id=24&name="
 19         // + URLEncoder.encode("大圆", "UTF-8");
 20         StringBuilder sb = new StringBuilder();
 21         for (Map.Entry<String, String> entry : params.entrySet()) {
 22             sb.append(entry.getKey()).append("=")
 23                     .append(URLEncoder.encode(entry.getValue(), encoding))
 24                     .append("&");
 25         }
 26         sb.deleteCharAt(sb.lastIndexOf("&"));
 27         byte[] data = sb.toString().getBytes();
 28         URL url = new URL(urlPath);
 29         HttpURLConnection conn = (HttpURLConnection) url.openConnection();
 30         conn.setRequestMethod("POST");
 31         conn.setReadTimeout(5 * 1000);
 32         conn.setDoOutput(true); // 发送POST请求， 必须设置允许输出
 33         conn.setUseCaches(false);
 34         conn.setRequestProperty("Connection", "Keep-Alive"); // 维持长链接
 35         conn.setRequestProperty("Charset", "UTF-8");
 36         // 设置输入参数的大小，把参数转化为字节数组
 37         conn.setRequestProperty("Content-Length", String.valueOf(data.length));
 38         // 设置数据类型
 39         conn.setRequestProperty("Content-Type",
 40                 "application/x-www-form-urlencoded");
 41         
 42         DataOutputStream outStream = new DataOutputStream(
 43                 conn.getOutputStream());
 44         outStream.write(data);
 45         outStream.flush();
 46         outStream.close();
 47         if (conn.getResponseCode() == RESPONSE_OK) {
 48             return conn.getInputStream();
 49         }
 50         return null;
 51     }
 52 
 53     /*
 54      * 得到http返回的输入流，并且转化成String
 55      */
 56     public static String getTextContent(String urlPath, String encoding)
 57             throws Exception {
 58         URL url = new URL(urlPath);
 59         HttpURLConnection conn = (HttpURLConnection) url.openConnection();
 60         conn.setRequestMethod("GET");
 61         conn.setReadTimeout(5 * 1000);
 62         if (conn.getResponseCode() == RESPONSE_OK) {
 63             InputStream inStream = conn.getInputStream();
 64             byte[] data = readStream(inStream);
 65             System.out.println(new String(data, encoding));
 66             return new String(data, encoding);
 67         }
 68         return null;
 69     }
 70 
 71     // 读取数据
 72     public static byte[] readStream(InputStream inStream) throws Exception {
 73         ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 74         byte[] buffer = new byte[2048];
 75         int length = -1;
 76         while ((length = (inStream.read(buffer))) != -1) {
 77             outStream.write(buffer, 0, length);
 78         }
 79         outStream.close();
 80         return outStream.toByteArray();
 81     }
 82 
 83     // 直接返回http得到的输入流
 84     public static InputStream getStreamContent(String urlPath, String encoding)
 85             throws Exception {
 86         InputStream inStream = null;
 87         URL url = new URL(urlPath);
 88         HttpURLConnection conn = (HttpURLConnection) url.openConnection();
 89         conn.setRequestMethod("GET");
 90         conn.setReadTimeout(5 * 1000);
 91         if (conn.getResponseCode() == RESPONSE_OK) {
 92             inStream = conn.getInputStream();
 93         }
 94         return inStream;
 95     }
 96 
 97     public static void print(String tag, String msg) {
 98         Log.d(tag, msg);
 99     }
100 }
101