android - 如何在 Android 中集成 RESTful Web 服务

Question

我是 Web 服务的新手。我想在 Android 中集成 Web 服务（REST）。谁能推荐一些好的教程。

Answer 1

什么后端？如果是 JAVA，那么您可以使用Jersey 将 REST 与 Java (JAX-RS) 结合使用。

在 Android 端，您可以使用这个简单的 RestClient来使用该 REST 服务。

对于 JSON <--> 双方（Android、Java 后端）的对象映射，您可以使用GSON。

Answer 2

另一个链接供您参考[[mkyong] 1

我为 HTTP POST 和 HTTP GET 做的示例代码

import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.ByteArrayEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;

import android.os.AsyncTask;
import android.util.Log;


public class HttpConnectionHandler {
    public static final String TAG = HttpConnectionHandler.class.getSimpleName();
    private ServerRequestCommand requestCommand;
    private HttpPost httpPost;
    private HttpGet httpGet;
    private HttpClient httpClient;
    private HttpResponse httpResponse;

    public HttpConnectionHandler(){
        HttpParams httpParameters = new BasicHttpParams();
        HttpConnectionParams.setConnectionTimeout(httpParameters, 5000);
        HttpConnectionParams.setSoTimeout(httpParameters, 5000);        
        this.httpClient = new DefaultHttpClient(httpParameters);
        //this.httpClient = new DefaultHttpClient();
    }

    private void doNetworkConnection(){
        new AsyncServerConnector().execute();
    }

    class AsyncServerConnector extends AsyncTask<String, String, String>{

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
        }

        @Override
        protected String doInBackground(String... arg0) {
            try {               
                if (Utility.isWifiPresent()
                        || Utility.isMobileConnectionPresent()) {
                    //Establish network connection here and set the response to request; if successful
                    //check GET or POST
                    if(requestCommand.getPostData() != null){
                        //means its POST
                        httpResponse = httpClient.execute(prepareHttpPost());
                    }else{
                        //its GET method
                        httpResponse = httpClient.execute(prepareHttpGet());
                    }
                    if(httpResponse != null){
                        int statusCode = httpResponse.getStatusLine().getStatusCode();
                        if(statusCode == HttpStatus.SC_OK){
                            InputStream inputStream = httpResponse.getEntity().getContent();
                            String serverResponse = formatServerResponse(inputStream);
                            requestCommand.setServerResponse(serverResponse);
                            requestCommand.setState(RequestCommand.STATE_SUCCESS);
                        }else{
                            requestCommand.setState(RequestCommand.STATE_SERVER_FAILURE);
                        }                       
                    }else{
                        requestCommand.setState(RequestCommand.STATE_SERVER_FAILURE);
                    }

                }
                //No network
                else{
                    requestCommand.setState(RequestCommand.STATE_NETWORK_FAILURE);
                }               
            } 
            catch (IOException e) {
                Log.i(TAG, "IOException during hitting for service: "+requestCommand.getServerUrl()+" and ID "+requestCommand.getRequestId());
                requestCommand.setState(RequestCommand.STATE_SERVER_FAILURE);
            }
            catch (Exception e) {
                Log.i(TAG, "Error during hitting for service: "+requestCommand.getServerUrl()+" and ID "+requestCommand.getRequestId());
                requestCommand.setState(RequestCommand.STATE_SERVER_FAILURE);
            }
            return null;
        }

        protected void onPostExecute(String file_url) {
            Log.i(TAG, "Get response for service: "+requestCommand.getServerUrl()+" and ID "+requestCommand.getRequestId());
            NetworkHandler.receiveResponseFromServer(requestCommand);
            requestCommand = null;
        }

    }

    public HttpPost prepareHttpPost() throws UnsupportedEncodingException {
        this.httpPost = new HttpPost("your url");       
        httpPost.setHeader("Content-Type", "application/json");
        httpPost.setEntity(new ByteArrayEntity(requestCommand.getPostData()
                .getBytes("UTF8")));
        return httpPost;
    }

    public HttpGet prepareHttpGet() {
        this.httpGet = new HttpGet(requestCommand.getServerUrl());      
        return httpGet;
    }

    private String formatServerResponse(InputStream inputStream) throws IOException {
        String serverResponse = null;
        StringBuffer responseBuffer = new StringBuffer();
        byte[] data = new byte[256];
        int len = 0;
        int size = 0;
        while (-1 != (len = inputStream.read(data))) {
            responseBuffer.append(new String(data, 0, len, "UTF-8"));
            size += len;
        }

        serverResponse = responseBuffer.toString();
        return serverResponse;
    }

}