I am calling rest web services from android . web service code is as follows
@Path("test")
public class Test
{
@GET
@Path("name/{name}")
@Produces(MediaType.TEXT_PLAIN)
public Response say(@PathParam("name") String name)
{
//return "Hello ......"+name;
ResponseBuilder response = Response.ok((Object)"Hello ......"+name);
return response.build();
}
}
Android client code is as follows
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URLEncoder;
import java.security.KeyStore;
import java.util.ArrayList;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpVersion;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.conn.ClientConnectionManager;
import org.apache.http.conn.scheme.PlainSocketFactory;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.scheme.SchemeRegistry;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;
import android.util.Log;
public class RestClient {
private static final int GET = 1;
private static final int POST = 2;
private ArrayList <NameValuePair> params;
private ArrayList <NameValuePair> headers;
private String url;
private int responseCode;
private String message;
private String response;
public String getResponse() {
return response;
}
public String getErrorMessage() {
return message;
}
public int getResponseCode() {
return responseCode;
}
public RestClient(String url)
{
this.url = url;
params = new ArrayList<NameValuePair>();
headers = new ArrayList<NameValuePair>();
}
public void AddParam(String name, String value)
{
params.add(new BasicNameValuePair(name, value));
}
public void AddHeader(String name, String value)
{
headers.add(new BasicNameValuePair(name, value));
}
public void Execute(int selection) throws Exception
{
switch(selection) {
case GET:
{
//add parameters
String combinedParams = "";
if(!params.isEmpty()){
combinedParams += "?";
for(NameValuePair p : params)
{
String paramString = p.getName() + "=" + URLEncoder.encode(p.getValue(),"UTF-8");
if(combinedParams.length() > 1)
{
combinedParams += "&" + paramString;
}
else
{
combinedParams += paramString;
}
}
}
HttpGet request = new HttpGet(url + combinedParams);
//add headers
for(NameValuePair h : headers)
{
request.addHeader(h.getName(), h.getValue());
}
Log.d("prabhu","url......"+url + combinedParams);
Log.d("prabhu","request......"+request);
executeRequest(request, url);
break;
}
case POST:
{
HttpPost request = new HttpPost(url);
//add headers
for(NameValuePair h : headers)
{
request.addHeader(h.getName(), h.getValue());
}
if(!params.isEmpty()){
request.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
}
executeRequest(request, url);
Log.d("prabhu","url......"+url);
break;
}
}
}
private void executeRequest(HttpUriRequest request, String url)
{
HttpClient client = null;
try
{
KeyStore trustStore = KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf = new MySSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, HTTP.UTF_8);
SchemeRegistry registry = new SchemeRegistry();
registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
registry.register(new Scheme("https", sf, 443));
ClientConnectionManager ccm = new ThreadSafeClientConnManager(params, registry);
client = new DefaultHttpClient(ccm, params);
}catch(Exception e)
{
}
HttpResponse httpResponse;
try {
httpResponse = client.execute(request);
responseCode = httpResponse.getStatusLine().getStatusCode();
message = httpResponse.getStatusLine().getReasonPhrase();
HttpEntity entity = httpResponse.getEntity();
if (entity != null) {
InputStream instream = entity.getContent();
response = convertStreamToString(instream);
// Closing the input stream will trigger connection release
instream.close();
}
} catch (ClientProtocolException e) {
client.getConnectionManager().shutdown();
e.printStackTrace();
} catch (IOException e) {
client.getConnectionManager().shutdown();
e.printStackTrace();
}
}
private static String convertStreamToString(InputStream is) {
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();
}
}
Using the above class, I am calling URL(web service) like below
RestClient client = new RestClient("http://localhost:8080/TestProject/test/name/madhu");
try {
client.Execute(GET)
} catch (Exception e) {
e.printStackTrace();
}
String response = client.getResponse();
If the server is running , every thing is working fine. But If Server is down ,how to handle the situation.