Question

我刚开始在Android中使用logcat和调试。我正在分析别人的代码，如下所示：

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class RestClient {



    private static String convertStreamToString(InputStream is) {
        /*
         * To convert the InputStream to String we use the BufferedReader.readLine()
         * method. We iterate until the BufferedReader return null which means
         * there's no more data to read. Each line will appended to a StringBuilder
         * and returned as String.
         */
        BufferedReader reader = new BufferedReader(new InputStreamReader(is));
        StringBuilder sb = new StringBuilder();

        String line = null;
        try {
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return sb.toString();
    }

    /* This is a test function which will connects to a given
     * rest service and prints it's response to Android Log with
     * labels "Praeda".
     */
    public static void connect(String url)
    {

        HttpClient httpclient = new DefaultHttpClient();

        // Prepare a request object
        HttpGet httpget = new HttpGet(url); 

        // Execute the request
        HttpResponse response;
        try {
            response = httpclient.execute(httpget);
            // Examine the response status
            Log.i("Praeda",response.getStatusLine().toString());

            // Get hold of the response entity
            HttpEntity entity = response.getEntity();
            // If the response does not enclose an entity, there is no need
            // to worry about connection release

            if (entity != null) {

                // A Simple JSON Response Read
                InputStream instream = entity.getContent();
                String result= convertStreamToString(instream);
                Log.i("Praeda",result);

                // A Simple JSONObject Creation
                JSONObject json=new JSONObject(result);
                Log.i("Praeda","<jsonobject>\n"+json.toString()+"\n</jsonobject>");

                // A Simple JSONObject Parsing
                JSONArray nameArray=json.names();
                JSONArray valArray=json.toJSONArray(nameArray);
                for(int i=0;i<valArray.length();i++)
                {
                    Log.i("Praeda","<jsonname"+i+">\n"+nameArray.getString(i)+"\n</jsonname"+i+">\n"
                            +"<jsonvalue"+i+">\n"+valArray.getString(i)+"\n</jsonvalue"+i+">");
                }

                // A Simple JSONObject Value Pushing
                json.put("sample key", "sample value");
                Log.i("Praeda","<jsonobject>\n"+json.toString()+"\n</jsonobject>");

                // Closing the input stream will trigger connection release
                instream.close();
            }


        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }


}

如何运行此操作以便查看日志？我是否需要实际调用函数或....我很困惑......

Answer 1

是的，您需要从活动中调用静态方法（例如Hello World）。活动运行后，您可以从logcat监控活动的日志输出（使用DDMS或adb）。

Answer 2

将其作为Android应用程序运行。单击Eclipse右上角的DDMS图标。在下一个窗口中单击LogCat。或者，OPEN->透视图（或工具栏上的视图） - ＆gt; Logcat。

Answer 3

是的，您需要创建一个新活动，并且必须调用此静态方法connect(String url)

RestClient.connect("http://www.example.com");

此外，对于logcat输出，请单击LogCat视图中的i。

使用logcat：这里有点困惑:(

3 个答案: