HttpGet adding header - java

I am creating a httpClient and I want to add certain header to my HttpGet request
My current code produces the following request.
GET /folder/index.html HTTP/1.0
Host: localhost:4444
Connection: Keep-Alive
User-Agent: Apache-HttpClient/4.2.1 (java 1.5)
What I want is to add another header (If-Modified-Since) in that request .
How can I do it?
Thank you :)
public String httpGet(String s) {
String url = s;
StringBuilder body = new StringBuilder();
httpclient = new DefaultHttpClient(); // create new httpClient
HttpGet httpGet = new HttpGet(url); // create new httpGet object
try {
response = httpclient.execute(httpGet); // execute httpGet
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
// System.out.println(statusLine);
body.append(statusLine + "\n");
HttpEntity e = response.getEntity();
String entity = EntityUtils.toString(e);
body.append(entity);
} else {
body.append(statusLine + "\n");
// System.out.println(statusLine);
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
httpGet.releaseConnection(); // stop connection
}
return body.toString(); // return the String
}

Use the setHeader() method on the HttpGet object like follows.
httpGet.setHeader("If-Modified-Since","11/26/2012");
I used this JavaDoc as a reference.

Use the setHeader() method on the HttpGet object like follows for the first one
httpGet.setHeader("If-Modified-Since","11/26/2012");
and then use addHeader() method on the HttpGet object like as follows for the second header.
httpGet.addHeader("If-Expires-On","11/26/2014");

Related

How to Return CloseableHttpResponse?

I have a method named getResponse() in my program:
public ClosableHTTPResponse getResponse()
{
RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(120 * 1000).build();
CloseableHttpClient httpClient = null;
CloseableHttpResponse response = null;
try {
httpClient = HttpClientBuilder.create().setDefaultRequestConfig(requestConfig).build();
HttpGet httpPostRequest = new HttpGet(getURL);
httpPostRequest.addHeader("Authorization", "Token " + APIKey);
httpPostRequest.setHeader("Content-type", "application/json");
response = httpClient.execute(httpPostRequest);
String statusLine = response.getStatusLine().toString();
System.out.println("Status Line Response: " + statusLine);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (response != null) response.close();
if (httpClient != null) httpClient.close();
}
return response;
}
}
When I call this method from external method in the following code:
public void analzyeReponseA()
{
CloseableHttpResponse response = null;
try {
response = getResponse("p1", "p2");
String OKResponse = "HTTP/1.1 200 OK";
String statusLine = response.getStatusLine().toString();
if (statusLine.contains(OKResponse)) {
HttpEntity entity = response.getEntity();
// java.net.SocketException: Socket is closed exception thrown on next line..
String responseString = EntityUtils.toString(entity, "UTF-8");
System.out.println("Response String:\n" + responseString);
}
}
I'm getting a java.net.SocketException: Socket is closed exception
on this line:
String responseString = EntityUtils.toString(entity, "UTF-8");
Based on this and this thread, presumably this is happening bec I call if (response != null) response.close(); in getResponse() method (correct?)
If so, my question now is how do I return a CloseableHttpResponse without the program throwing above exception? Is the only option to call String responseString = EntityUtils.toString(entity, "UTF-8"); in getReponse() method and return a responseString instead of CloseableHttpResponse? What if I still want to access the response object in caller code (like to check status line or something else)?
If I understood the question correctly, I'd first look to see if the code really needed to return an HttpResponse. If the method(s) that call getResponse() all only need, e.g, the contents, then return the contents rather than the response.
Otherwise, you should be able to do, using the try-with-resources approach:
public void callingMethod() {
try (CloseableHttpResponse resp = getResponse();) {
{
// example
HttpEntity entity = resp.getEntity();
}
}
And remove the close from the getResponse() method.
Also, you do not want to be opening/closing the HttpClient on each invocation. That class is designed to be used multiple times. There is more information at You're Using HttpClient wrong and it is destabilizing your software. Thus, you may wish to refactor the code to move the HttpClient elsewhere.

Android HttpsURLConnection - simple POST request with parameters

I've been trying to get a simple android client server app working, and I've had nothing but trouble. I'm hoping someone can look at this code and see what I'm doing wrong, maybe I'm doing things in the wrong order, or forgetting something? Just adding the relevant parts
HttpsURLConnection conn = (HttpsURLConnection) url.openConnection();
conn.addRequestProperty("Content-Type", "application/json");
// set some made up parameters
String str = "{'login':'superman#super.com','password':'password'}";
byte[] outputInBytes = str.getBytes("UTF-8");
OutputStream os = conn.getOutputStream();
os.write( outputInBytes );
os.close();
// connection.setDoOutput(true); //should trigger POST - move above -> crash
conn.setRequestMethod("POST"); // explicitly set POST -move above so we can set params -> crash
conn.setDoInput(true);
The error I get is
'exception: java.net.ProtocolException: method does not support a
request body: GET'
If I just do a POST request without parameters it's fine, so I guess I should move the connection.setDoOutput(true); or conn.setRequestMethod("POST"); higher up, that should work right? When I do that I get the error:
exception: java.net.ProtocolException: Connection already established.
So, if I try to set to POST before adding parameters it doesn't work, if I try to do it after it doesn't work... what am I missing? Is there another way I should be doing this? Am I adding parameters incorrectly? I've been searching for a simple android networking example, and I can't find any, is there any example the official Android site? All I want to do is a very basic network operation, this is so frustrating!
EDIT: I need to use HttpsURLConnection for reasons not included in the above code- I need to authenticate, trust hosts, etc- so I'm really looking for a potential fix for the above code if possible.
Here is an example of how to post with a JSON Object:
JSONObject payload=new JSONObject();
try {
payload.put("password", params[1]);
payload.put("userName", params[0]);
} catch (JSONException e) {
e.printStackTrace();
}
String responseString="";
try
{
HttpPost httpPost = new HttpPost("www.theUrlYouQWant.com");
httpPost.setEntity(new StringEntity(payload.toString()));
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
HttpResponse response = new DefaultHttpClient().execute(httpPost);
responseString = EntityUtils.toString(response.getEntity());
}
catch (ClientProtocolException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
And example of how to get
String responseString = "";
//check if the username exists
StringBuilder builder = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet("www.theUrlYouQWant.com");
ArrayList<String> existingUserName = new ArrayList<String>();
try
{
HttpResponse response = client.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
builder.append(line);
}
}
else
{
Log.e(ParseException.class.toString(), "Failed to download file");
}
}
catch (ClientProtocolException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
I followed this tutorial on making http calls:
http://www.androidhive.info/2012/01/android-json-parsing-tutorial/
Works fine with no problems.
Below is a class that I have modified from the sample:
public class ServiceHandler {
static String response = null;
public final static int GET = 1;
public final static int POST = 2;
String TAG = ((Object) this).getClass().getSimpleName();
public ServiceHandler() {
}
/**
* Making service call
*
* #url - url to make request
* #method - http request method
*/
public String makeServiceCall(String url, int method) {
return this.makeServiceCall(url, method, null);
}
/**
* Making service call
*
* #url - url to make request
* #method - http request method
* #params - http request params
*/
public String makeServiceCall(String url, int method,
List<NameValuePair> params) {
try {
// http client
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 = 2000;
HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
// Set the default socket timeout (SO_TIMEOUT)
// in milliseconds which is the timeout for waiting for data.
int timeoutSocket = 2000;
HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);
DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
// Checking http request method type
if (method == POST) {
HttpPost httpPost = new HttpPost(url);
// adding post params
if (params != null) {
httpPost.setEntity(new UrlEncodedFormEntity(params));
}
httpResponse = httpClient.execute(httpPost);
} else if (method == GET) {
// appending params to url
if (params != null) {
String paramString = URLEncodedUtils
.format(params, "utf-8");
url += "?" + paramString;
}
Log.e("Request: ", "> " + url);
HttpGet httpGet = new HttpGet(url);
httpResponse = httpClient.execute(httpGet);
}
if (httpResponse != null) {
httpEntity = httpResponse.getEntity();
} else {
Log.e(TAG, "httpResponse is null");
}
response = EntityUtils.toString(httpEntity);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return response;
}
}
And this is how I use the class:
nameValuePairs = new ArrayList<NameValuePair>();
String param_value = "value";
String param_name = "name";
nameValuePairs.add(new BasicNameValuePair(param_name, param_value));
// Creating service handler class instance
sh = new ServiceHandler();
String json = sh.makeServiceCall(Utils.getUrl, ServiceHandler.GET, nameValuePairs);

Parse Json Arabic text

I can't parse Arabic/Persian text from SQL database. Everything is set to UTF-8. My SQL database text is set to utf8_general_ci. JSON parser is set to UTF-8 too.
Text is shown good in English. But when I use Arabic/Persian text in database, android shows text as ???????.
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET method
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method == "POST"){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method == "GET"){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
I have been r & d around a day and finally success to parse my arabic json response getting from server using following code.So, may be helpful to you.
HttpParams params = new BasicHttpParams();
HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
HttpProtocolParams.setContentCharset(params, "UTF-8");
params.setBooleanParameter("http.protocol.expect-continue", false);
HttpClient httpclient = new DefaultHttpClient(params);
HttpPost httppost = new HttpPost(Your_URL);
HttpResponse http_response= httpclient.execute(httppost);
HttpEntity entity = http_response.getEntity();
String jsonText = EntityUtils.toString(entity, HTTP.UTF_8);
Log.i("Response", jsonText);
Now, use jsonText for your further requirement.
Thank You
Maybe the problem is on server side. Check the raw String you got from the Server to see if it is correctly formatted.
I think it can help you by storing it as clob/blob, since once you have the bytes which were convereted from UTF-8 at server side, any client side code can also then using various String encoding formats to display the test.
Or my other advice, use a webview to display it, its more mature to handle these nuances.

Android - Http Get Request

I'm trying to Get Request with code below but the stringbuilder is always null. The url is correct...
http://pastebin.com/mASvGmkq
EDIT
public static StringBuilder sendHttpGet(String url) {
HttpClient http = new DefaultHttpClient();
StringBuilder buffer = null;
try {
HttpGet get = new HttpGet(url);
HttpResponse resp = http.execute(get);
buffer = inputStreamToString(resp.getEntity().getContent());
}
catch(Exception e) {
debug("ERRO EM GET HTTP URL:\n" + url + "\n" + e);
return null;
}
debug("GET HTTP URL OK:\n" + buffer);
return buffer;
}
I usually do it like this:
try {
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
output = EntityUtils.toString(httpEntity);
}
where output is a String-object.

httpPost Method

I am creating httpClient and when I send httpPost method, how can I attach a body to the httpRequest ??
public String httpPost(String URL, String BODY) {
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(URL);
try {
response = httpclient.execute(httpPost); // get response from executing client
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == HttpStatus.SC_OK) {
body.append(statusLine + "\n");
HttpEntity e = response.getEntity();
String entity = EntityUtils.toString(e);
body.append(entity);
} else {
body.append(statusLine + "\n");
// System.out.println(statusLine);
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
httpPost.releaseConnection();
}
return body.toString();
}
For example, the string is
" < html > < header > Header < /header> < body> I am body < /body> "
Where do I attach that string to the request message ?
Thank you :)
You can create a StringEntity, set it to the HttpPost object, and set the correct Content-Type:
StringEntity entity = new StringEntity("data=" + java.net.URLEncoder.encode(body, "utf-8"));
entity.setContentType("application/x-www-form-urlencoded");
httpPost.setEntity(entity);
And then send your POST request as usual.
Have you tried httpPost.setEntity(" < html > < header > Header < /header> < body> I am body < /body> ") before your try-catch?
I'm not entirely sure what "entity" refers to, but that's the best I can come up with from looking at the documentation here

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