I am absolutely new to android development and I need help in know how can I invoke a remote servlet which is gonna send me data from a database in the form of xml. I am a beginner and I don't understand jargon. If possible provide me with a link/tutorial for the same.
Any help is greatly appreciated, Thanks!
you need to do this while making a get request.
public boolean funtionAtSite(String sentUrl) {
String url = sentUrl;
HttpGet getMethod = new HttpGet(url);
DefaultHttpClient client = new DefaultHttpClient();
try {
ResponseHandler<String> reponseHandler = new BasicResponseHandler();
String responseBody = client.execute(getMethod, reponseHandler);
/******** now do what you want to do with response **********/
if (responseBody.equalsIgnoreCase("1")) {
Log.v(TAG, responseBody);
return true;
}
return false;
} catch (Throwable t) {
return false;
}
}
Related
I want to know if it is possible to send SEARCH request (practically) through java.net.HttpURLConnection to HTTP-based URL.
I have read so many articles describing that how to send GET, POST, DELETE requests but I still haven't found any sample code which successfully performs SEARCH request.
here is sample code.
public static String HTTPSearch(String urlAddress, String... searchDataPair) {
HttpParams myParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(myParams, 10000);
HttpConnectionParams.setSoTimeout(myParams, 30000);
DefaultHttpClient hc = new DefaultHttpClient(myParams);
ResponseHandler<String> res = new BasicResponseHandler();
HttpSearch searchMethod = new HttpSearch (urlAddress);
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(
putDataPair.length / 2);
for (int i = 0; i < putDataPair.length; i += 2) {
nameValuePairs.add(new BasicNameValuePair(searchDataPair[i],
searchDataPair[i + 1]));
}
String response = "";
try {
searchMethod .setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = hc.execute(searchMethod , res);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
in this code, HttpSearch is error.
please help me about HttpSearch.
First, i dont know whether my approach is best or not.
Im using restful codeigniter webservice. What i did to implement search is by using POST. I simply POST the search keyword and then my webservice will perform SQL Query to search that String (keyword) im my database.
According to the docs, the setRequestMethod() does not allow for the SEARCH method (which makes sense, since from what I can tell SEARCH is MS only. However, you can always try to use setRequestMethod() and see what happens.
I try to get string from this url:
http://autoc.finance.yahoo.com/autoc?query=google&callback=YAHOO.Finance.SymbolSuggest.ssCallback
When I look at this in Chrome, I see correct JavaScript responce but when download it from the app with the same headers, I get binary response. How can I get the same correct response in the app?
EDIT:
Code:
public RESTResponse<T> get(String url) {
HttpGet get = new HttpGet(url);
setHeaders(get);
return execute(get);
}
private void setHeaders(HttpRequestBase request) {
request.setHeader("Accept", "text/html,application/xhtml+xml,application/xml");
request.setHeader("Accept-Encoding", "gzip,deflate,sdch");
request.setHeader("Accept-Charset", "UTF-8");
}
private RESTResponse<T> execute(HttpRequestBase request) {
DefaultHttpClient client = new DefaultHttpClient();
try {
HttpResponse response = client.execute(request);
return responseFactory.create(response);
} catch (IOException e) {
throw new RuntimeException("Can't perform request.", e);
}
}
hard to tell what's the problem without seeing your code - but you could use that one:
https://github.com/ligi/LigiAndroidCommons/blob/master/src/org/ligi/android/common/net/NetHelper.java
I am trying to send data to my server using HttpPost via the following code.
private boolean FacebookLogin(String url) {
boolean isDataSend = false;
try {
HttpClient client = new DefaultHttpClient();
HttpPost request = new HttpPost(url);
List<NameValuePair> value = new ArrayList<NameValuePair>();
value.add(new BasicNameValuePair("data", FacebookData()));
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(value);
request.setEntity(entity);
HttpResponse res = client.execute(request);
if (res.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
String bufstring = EntityUtils.toString(res.getEntity(),
"UTF-8");
isDataSend = true;
}
} catch (Exception e) {
}
return isDataSend;
}
Is there any way i can have a look at how the $_POST looks on the server end. so that it will be easier for me to code the server part.
You can write the received $_POST on a file. Sometimes I do that. It's not the most elegant solution, but it works fine.
Try using a http proxy (e.g. Fiddler) for debugging, it helps a lot in these cases. You can set up an emulator to use this proxy for network communications, so you can inspect the messages sent and received. Check out the emulator docs on how to configure it to use a proxy.
I have Java web application server [ acts like server ].
In Android application, using httppost i have calling the restwebserive server.
My calling is hit the webservice with the response code 200.
Now i want to pass the java class object as like parameter.
sample java class:
public Class Sample{
public String Username;
public String getUsername()
{
return Username;
}
public void setUsername(String user){
this.Username = user;
}}
Used code :[ Is not passing my class object to server ]
Sample sam = new Sample();
sam.setUsername("Test");
JSONObject json = new JSONObject();
json.put("Sample", sam);
StringEntity se = new StringEntity(json.toString());
Httppostrequest.setEntity(se);
when i debugging the server the sample object parameter input is empty.[Not passed properly]
How to pass the class object via http post in android?
Please help me on this.
Thanks in advance,
Kums
if you use apache library you can do it one line
JSONSerializer.toJSON(sam);
otherwise i think you have to send it as
Sample sam = new Sample();
sam.setUsername("Test");
JSONObject json = new JSONObject();
json.put("sample", sam.getUserName());
StringEntity se = new StringEntity(json.toString());
Httppostrequest.setEntity(se);
Here is a code snippet
public void callWebService(String q){
HttpClient httpclient = new DefaultHttpClient();
HttpGet request = new HttpGet(URL + q);
request.addHeader("deviceId", deviceId);
ResponseHandler<string> handler = new BasicResponseHandler();
try {
result = httpclient.execute(request, handler);
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
httpclient.getConnectionManager().shutdown();
Log.i(tag, result);
} // end callWebService()
}
Use this method to call your webservice
I have built a library for doing async requests, you can send parameter requests as www.somedomain.com/action?param1="somevalue" etc.. and also there is the option to use string body.
https://github.com/darko1002001/android-rest-client
Check it out, it might be helpful.
I'm trying to figure out how to POST JSON from Android by using HTTPClient. I've been trying to figure this out for a while, I have found plenty of examples online, but I cannot get any of them to work. I believe this is because of my lack of JSON/networking knowledge in general. I know there are plenty of examples out there but could someone point me to an actual tutorial? I'm looking for a step by step process with code and explanation of why you do each step, or of what that step does. It doesn't need to be a complicated, simple will suffice.
Again, I know there are a ton of examples out there, I'm just really looking for an example with an explanation of what exactly is happening and why it is doing that way.
If someone knows about a good Android book on this, then please let me know.
Thanks again for the help #terrance, here is the code I described below
public void shNameVerParams() throws Exception{
String path = //removed
HashMap params = new HashMap();
params.put(new String("Name"), "Value");
params.put(new String("Name"), "Value");
try {
HttpClient.SendHttpPost(path, params);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
In this answer I am using an example posted by Justin Grammens.
About JSON
JSON stands for JavaScript Object Notation. In JavaScript properties can be referenced both like this object1.name and like this object['name'];. The example from the article uses this bit of JSON.
The Parts
A fan object with email as a key and foo#bar.com as a value
{
fan:
{
email : 'foo#bar.com'
}
}
So the object equivalent would be fan.email; or fan['email'];. Both would have the same value
of 'foo#bar.com'.
About HttpClient Request
The following is what our author used to make a HttpClient Request. I do not claim to be an expert at all this so if anyone has a better way to word some of the terminology feel free.
public static HttpResponse makeRequest(String path, Map params) throws Exception
{
//instantiates httpclient to make request
DefaultHttpClient httpclient = new DefaultHttpClient();
//url with the post data
HttpPost httpost = new HttpPost(path);
//convert parameters into JSON object
JSONObject holder = getJsonObjectFromMap(params);
//passes the results to a string builder/entity
StringEntity se = new StringEntity(holder.toString());
//sets the post request as the resulting string
httpost.setEntity(se);
//sets a request header so the page receving the request
//will know what to do with it
httpost.setHeader("Accept", "application/json");
httpost.setHeader("Content-type", "application/json");
//Handles what is returned from the page
ResponseHandler responseHandler = new BasicResponseHandler();
return httpclient.execute(httpost, responseHandler);
}
Map
If you are not familiar with the Map data structure please take a look at the Java Map reference. In short, a map is similar to a dictionary or a hash.
private static JSONObject getJsonObjectFromMap(Map params) throws JSONException {
//all the passed parameters from the post request
//iterator used to loop through all the parameters
//passed in the post request
Iterator iter = params.entrySet().iterator();
//Stores JSON
JSONObject holder = new JSONObject();
//using the earlier example your first entry would get email
//and the inner while would get the value which would be 'foo#bar.com'
//{ fan: { email : 'foo#bar.com' } }
//While there is another entry
while (iter.hasNext())
{
//gets an entry in the params
Map.Entry pairs = (Map.Entry)iter.next();
//creates a key for Map
String key = (String)pairs.getKey();
//Create a new map
Map m = (Map)pairs.getValue();
//object for storing Json
JSONObject data = new JSONObject();
//gets the value
Iterator iter2 = m.entrySet().iterator();
while (iter2.hasNext())
{
Map.Entry pairs2 = (Map.Entry)iter2.next();
data.put((String)pairs2.getKey(), (String)pairs2.getValue());
}
//puts email and 'foo#bar.com' together in map
holder.put(key, data);
}
return holder;
}
Please feel free to comment on any questions that arise about this post or if I have not made something clear or if I have not touched on something that your still confused about... etc whatever pops in your head really.
(I will take down if Justin Grammens does not approve. But if not then thanks Justin for being cool about it.)
Update
I just happend to get a comment about how to use the code and realized that there was a mistake in the return type.
The method signature was set to return a string but in this case it wasnt returning anything. I changed the signature
to HttpResponse and will refer you to this link on Getting Response Body of HttpResponse
the path variable is the url and I updated to fix a mistake in the code.
Here is an alternative solution to #Terrance's answer. You can easly outsource the conversion. The Gson library does wonderful work converting various data structures into JSON and the other way around.
public static void execute() {
Map<String, String> comment = new HashMap<String, String>();
comment.put("subject", "Using the GSON library");
comment.put("message", "Using libraries is convenient.");
String json = new GsonBuilder().create().toJson(comment, Map.class);
makeRequest("http://192.168.0.1:3000/post/77/comments", json);
}
public static HttpResponse makeRequest(String uri, String json) {
try {
HttpPost httpPost = new HttpPost(uri);
httpPost.setEntity(new StringEntity(json));
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
return new DefaultHttpClient().execute(httpPost);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
Similar can be done by using Jackson instead of Gson. I also recommend taking a look at Retrofit which hides a lot of this boilerplate code for you. For more experienced developers I recommend trying out RxAndroid.
I recommend using this HttpURLConnectioninstead HttpGet. As HttpGet is already deprecated in Android API level 22.
HttpURLConnection httpcon;
String url = null;
String data = null;
String result = null;
try {
//Connect
httpcon = (HttpURLConnection) ((new URL (url).openConnection()));
httpcon.setDoOutput(true);
httpcon.setRequestProperty("Content-Type", "application/json");
httpcon.setRequestProperty("Accept", "application/json");
httpcon.setRequestMethod("POST");
httpcon.connect();
//Write
OutputStream os = httpcon.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
writer.write(data);
writer.close();
os.close();
//Read
BufferedReader br = new BufferedReader(new InputStreamReader(httpcon.getInputStream(),"UTF-8"));
String line = null;
StringBuilder sb = new StringBuilder();
while ((line = br.readLine()) != null) {
sb.append(line);
}
br.close();
result = sb.toString();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Too much code for this task, checkout this library https://github.com/kodart/Httpzoid
Is uses GSON internally and provides API that works with objects. All JSON details are hidden.
Http http = HttpFactory.create(context);
http.get("http://example.com/users")
.handler(new ResponseHandler<User[]>() {
#Override
public void success(User[] users, HttpResponse response) {
}
}).execute();
There are couple of ways to establish HHTP connection and fetch data from a RESTFULL web service. The most recent one is GSON. But before you proceed to GSON you must have some idea of the most traditional way of creating an HTTP Client and perform data communication with a remote server. I have mentioned both the methods to send POST & GET requests using HTTPClient.
/**
* This method is used to process GET requests to the server.
*
* #param url
* #return String
* #throws IOException
*/
public static String connect(String url) throws IOException {
HttpGet httpget = new HttpGet(url);
HttpResponse response;
HttpParams httpParameters = new BasicHttpParams();
// Set the timeout in milliseconds until a connection is established.
// The default value is zero, that means the timeout is not used.
int timeoutConnection = 60*1000;
HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT)
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 60*1000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
HttpClient httpclient = new DefaultHttpClient(httpParameters);
try {
response = httpclient.execute(httpget);
HttpEntity entity = response.getEntity();
if (entity != null) {
InputStream instream = entity.getContent();
result = convertStreamToString(instream);
//instream.close();
}
}
catch (ClientProtocolException e) {
Utilities.showDLog("connect","ClientProtocolException:-"+e);
} catch (IOException e) {
Utilities.showDLog("connect","IOException:-"+e);
}
return result;
}
/**
* This method is used to send POST requests to the server.
*
* #param URL
* #param paramenter
* #return result of server response
*/
static public String postHTPPRequest(String URL, String paramenter) {
HttpParams httpParameters = new BasicHttpParams();
// Set the timeout in milliseconds until a connection is established.
// The default value is zero, that means the timeout is not used.
int timeoutConnection = 60*1000;
HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT)
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 60*1000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
HttpClient httpclient = new DefaultHttpClient(httpParameters);
HttpPost httppost = new HttpPost(URL);
httppost.setHeader("Content-Type", "application/json");
try {
if (paramenter != null) {
StringEntity tmp = null;
tmp = new StringEntity(paramenter, "UTF-8");
httppost.setEntity(tmp);
}
HttpResponse httpResponse = null;
httpResponse = httpclient.execute(httppost);
HttpEntity entity = httpResponse.getEntity();
if (entity != null) {
InputStream input = null;
input = entity.getContent();
String res = convertStreamToString(input);
return res;
}
}
catch (Exception e) {
System.out.print(e.toString());
}
return null;
}