Java读取网络数据（新浪网址）InputStream的数据流操作实录笔记（一） 分享出来供大家参考！

package sina.jsontest.test; import java.io.IOException; import java.io.InputStream; import java.util.Iterator; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import org.codehaus.jackson.JsonNode; import org.codehaus.jackson.JsonParseException; import org.codehaus.jackson.map.JsonMappingException; import org.codehaus.jackson.map.ObjectMapper; public class NetWorkOperator { /** * @reference * 1.<a href="http://www.cnblogs.com/MyFavorite/archive/2010/10/19/1855758.html">http://www.cnblogs.com/MyFavorite/archive/2010/10/19/1855758.html</a><br> * 2.<a href="http://www.blogjava.net/pengpenglin/archive/2008/12/16/220350.html">http://www.blogjava.net/pengpenglin/archive/2008/12/16/220350.html</a><br> * @param args * @throws Exception */ public static void main(String[] args)throws Exception { NetWorkOperator kx=new NetWorkOperator(); String json=kx.getReponse(SinaJsonTest.SinaUrl); kx.JSONNodeParse(json); } /** * <b>获取指定的URL返回的数据信息</b> * @param <font color="#efac10"><a href="http://www.baidu.com">_url:指定的URL</a></font> * @return * @throws ClientProtocolException * @throws IOException */ public String getReponse(String _url) throws ClientProtocolException, IOException { String readContent=null; DefaultHttpClient httpclient = new DefaultHttpClient(); HttpGet httpget = new HttpGet(SinaJsonTest.SinaUrl); System.out.println("0.Send the URL to Sina Sever...."); HttpResponse response = httpclient.execute(httpget); HttpEntity entity = response.getEntity(); System.out.println("1.Get Response Status: " + response.getStatusLine()); if (entity != null) { System.out.println(" Get ResponseContentEncoding():"+entity.getContentEncoding()); System.out.println(" Content Length():"+entity.getContentLength()); //getResponse InputStream in=entity.getContent(); int count = 0; while (count == 0) { count = Integer.parseInt(""+entity.getContentLength());//in.available(); } byte[] bytes = new byte[count]; int readCount = 0; // 已经成功读取的字节的个数 while (readCount <= count) { if(readCount == count)break; readCount += in.read(bytes, readCount, count - readCount); } //转换成字符串 readContent= new String(bytes, 0, readCount, "UTF-8"); // convert to string using bytes System.out.println("2.Get Response Content():\n"+readContent); } return readContent; } /** * @core 重点用到了readTree方法: * 1.从文件读取 * ObjectMapper mapper = new ObjectMapper(); * JsonFactory f = new JsonFactory(); * JsonParser jp = f.createJsonParser(new File(fileName)); * JsonNode root = mapper.readTree(jp); * 2.从字符串读取 * ObjectMapper mapper = new ObjectMapper(); * JsonNode userRootNode = mapper.readTree(json); * <br/><font color='red'>Java JSON</font> * @param <cite>fileName</cite>=<b>FilePath+FileName</b> */ public void JSONNodeParse(String json) { try { ObjectMapper mapper = new ObjectMapper(); JsonNode root = mapper.readTree(json); System.out.println("Source:\n"+root.toString()); JsonNode userInfoNode = root.path("users").get(0); System.out.println("userInfo:" + userInfoNode.toString());// 还可以继续解析 int next_cursor = root.path("next_cursor").getIntValue(); System.out.println("next_cursor:" + next_cursor); JsonNode previous_cursorNode = root.path("previous_cursor"); System.out.println("previous_cursorNode:" + previous_cursorNode.getIntValue()); for (JsonNode node : root.path("users")) { System.out.println("Full Entry: " + node.toString()); // 解析userInfoNode String sub_json = node.toString(); try { JsonNode userRootNode = mapper.readTree(sub_json); System.out.println("UserRoot Node Size:"+ userRootNode.size()); Iterator<String> itr = null; for (JsonNode _node : userRootNode) { itr=_node.getFieldNames(); //System.out.println("Entry(followers_count): " // + _node.path("followers_count").getValueAsText()); while (itr.hasNext()) { String fieldName = itr.next(); if(fieldName.equals("province")) System.out.println("province exists!"); if (_node.path(fieldName).toString().startsWith("\"") && _node.path(fieldName).toString().endsWith("\"")) System.out.println("Entry("+ fieldName+ "): " + _node.path(fieldName).toString().substring( 1,_node.path(fieldName).toString().length() - 1)); else System.out.println("Entry(" + fieldName + "): " + _node.path(fieldName).toString()); } } } catch (JsonParseException e) { e.printStackTrace(); } catch (JsonMappingException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } } catch (JsonParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }

用到的 *.jar 包如下：

Eclipse测试通过！分享出来供大家参考。