Java CURL request using HTTP - java

I am trying to perform a CURL request using Java. The CURL request is as follows:
curl https://apis.sen.se/v2/feeds/N4hSBSpFlYzXT6ZN2IA1KadgSR9rTazv/events/?limit=1 -u username:password
I am trying to perform the request as follows:
String stringUrl = "https://apis.sen.se/v2/feeds/N4hSBSpFlYzXT6ZN2IA1KadgSR9rTazv/events/?limit=1";
URL url = new URL(stringUrl);
URLConnection uc = url.openConnection();
uc.setRequestProperty("X-Requested-With", "Curl");
String userpass = "username" + ":" + "password";
String basicAuth = "Basic " + new String(new Base64().encode(userpass.getBytes()));
uc.setRequestProperty("Authorization", basicAuth);
InputStreamReader inputStreamReader = new InputStreamReader(uc.getInputStream());
and I am trying to see the contents of inputStreamReader as follows:
int data = inputStreamReader.read();
char aChar = (char) data;
System.out.println(aChar);
The code is compiling and running fine, but it is returning nothing. Where am I going wrong?

I ended up getting it working using the following code:
public static void main(String args[]) throws IOException {
String stringUrl = "url";
URL url = new URL(stringUrl);
URLConnection uc = url.openConnection();
uc.setRequestProperty("X-Requested-With", "Curl");
String userpass = "username" + ":" + "password";
String basicAuth = "Basic " + new String(new Base64().encode(userpass.getBytes()));
uc.setRequestProperty("Authorization", basicAuth);
StringBuilder html = new StringBuilder();
BufferedReader input = null;
try {
input = new BufferedReader(new InputStreamReader(uc.getInputStream()));
String htmlLine;
while ((htmlLine = input.readLine()) != null) {
html.append(htmlLine);
}
}
catch (IOException e) {
e.printStackTrace();
}
finally {
try {
input.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
System.out.println(html.toString());
}

I was also trying to do that thing. I have some kind of workaround but it reads everything it sees.
--Here's the code---
String params = "some-parameters";
URL url = new URL("some-website");
HttpURLConnection con = (HttpURLConnection) url.openConnection();
con.setRequestMethod("POST");
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(params);
wr.flush();
wr.close();
con.getResponseCode();
BufferedReader reader = new BufferedReader(new InputStreamReader(con.getInputStream()));
String line;
StringBuffer buffer = new StringBuffer();
while((line = reader.readLine()) != null) {
buffer.append(line+"\n");
}
reader.close();
System.out.print(buffer.toString());
--Notice, I use this code to see if a certain account exist on a certain website, since it outputs everything, what I do is to find a specific regularity upon the code which could tell me if that user exist or not. Well I'm not really even sure if this could help you, but it might be. Good Luck...

Related

dealing with korean text breaking words (like ???)

I'm using api to get xml.
but English text is okay to get xml
and also number text is okay
however korean text can't get
this is my code
StringBuffer result = new StringBuffer();
try {
String urlstr = "https://openapi.gg.go.kr/OrganicAnimalProtectionFacilit?" +
"KEY=secret" +
"&Type=xml" +
"&pIndex=1"+
"&pSize=100";
URL url = new URL(urlstr);
HttpURLConnection urlconnection = (HttpURLConnection) url.openConnection();
urlconnection.setRequestMethod("GET");
BufferedReader br = new BufferedReader(new InputStreamReader(urlconnection.getInputStream(), StandardCharsets.UTF_8 ));
String returnLine;
result.append("<xmp>");
while((returnLine = br.readLine())!=null) {
result.append(returnLine+"\n");
}
urlconnection.disconnect();
}catch(Exception e) {
e.printStackTrace();
}
return result+"</xmp>";

make an HttpsURLConnection request with parameters by method post

process an https page sending its parameters
Java8u201 using HttpsURLConnection
String httpsURL = "https://www.wmtechnology.org/Consultar-RUC/";
URL myUrl = null;
String[][] parameter = { { "modo", "1" }, { "btnBuscar", "Buscar" }, { "nruc", "10460332759" } };
System.out.println(parameter.toString());
try {
myUrl = new URL(httpsURL);
HttpsURLConnection conn = (HttpsURLConnection) myUrl.openConnection();
conn.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(conn.getOutputStream());
wr.writeBytes(parameter.toString());
wr.flush();
wr.close();
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
String inputLine;
while ((inputLine = br.readLine()) != null) {
System.out.println(inputLine);
}
br.close();
} catch (IOException e) {
e.printStackTrace();
}
returns the page but without data
Consider using a library which handles the underlying connection/request for you. The Apache HTTP Client has a fluent API which would make the code easier to write:
String result = Request
.Post("https://www.wmtechnology.org/Consultar-RUC/")
.bodyForm(Form
.form()
.add("modo", "1")
.add("btnBuscar", "Buscar")
.add("nruc", "10460332759")
.build())
.execute()
.returnContent()
.asString();
System.out.println(result);
More information here: https://hc.apache.org/httpcomponents-client-4.2.x/tutorial/html/fluent.html
This request does return data.
You are wrong on the line
wr.writeBytes(parameter.toString());
because parameter.toString() returns string like [[Ljava.lang.String;#1f554b06 instead of expected param1=value1&param2=value2 etc.
So correct this part to
String parameterString = Arrays.stream(parameter)
.map(pair -> pair[0] + "=" + pair[1])
.collect(Collectors.joining("&"));
wr.writeBytes(parameter.toString());

HttpURLConnection update from Http Client

Hello I was wondering if somebody could help me with the following, I have a database that is currently populated. I used to call it using the http client and it worked fine but now I'm trying to update the code since its been deprecated to use the httpurlconnection but i have no success. I ve looked up some tutorials and tried a few thing but it doesn't seem to be working. the database is called through a php file and returns it in a json format.If i were to call the php file from my browser the response is the following: [{"id":"15","logo":"logo url","title":"title"}]
The error that I get on the console is the following:java.lang.NullPointerException: Attempt to invoke virtual method 'void java.io.InputStream.close()' on a null object reference
Which its not making much sense to me since the script pulls information
I have the following code, i left the commented section just in case i need any of it, It also includes the old way i used to call the DB Thank you!:
public void loadNews(){
InputStream is = null;
String result = "";
ArrayList<NameValuePair>();
try {
URL url = new URL("http://databasecall.php");
//HttpClient httpclient = new DefaultHttpClient();
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
//urlConnection.setRequestMethod("GET");
//urlConnection.setRequestProperty("Content-length", "0");
//urlConnection.setUseCaches(false);
//urlConnection.setAllowUserInteraction(false);
//urlConnection.setConnectTimeout(15000);
//urlConnection.setReadTimeout(15000);
//urlConnection.connect();
int responseCode = urlConnection.getResponseCode();
Log.i("Tag:", Integer.toString(responseCode)); //tag 200
//HttpPost httppost = new HttpPost("http://databasecall.php");
//httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
//HttpResponse response = httpclient.execute(httppost);
//HttpEntity entity = response.getEntity();
//is = entity.getContent();
/*}catch(Exception e){
Log.e("log_tag", "Error in http connection "+e.toString());
}*/
//convert response to string
//try{
//BufferedReader reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
if (responseCode == HttpURLConnection.HTTP_OK) {
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
//BufferedReader reader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
result = sb.toString();
Log.i("Tag:", result);
}
}catch(Exception e){
Log.e("log_tag", "Error converting result " + e.toString());
}
Updated API
try {
String urlParameters = "name=toni&class=one&param3=ok";
byte[] postData = urlParameters.getBytes(Charset.forName("UTF-8"));
int postDataLength = postData.length;
String request = "http://rocks.php";
URL url = new URL(request);
HttpURLConnection cox = (HttpURLConnection) url.openConnection();
cox.setDoOutput(true);
cox.setDoInput(true);
cox.setInstanceFollowRedirects(false);
cox.setRequestMethod("POST");
cox.setRequestProperty("Content-Type",
"application/x-www-form-urlencoded");
cox.setRequestProperty("charset", "utf-8");
cox.setRequestProperty("Content-Length",
Integer.toString(postDataLength));
cox.setUseCaches(false);
OutputStreamWriter writer = new OutputStreamWriter(
cox.getOutputStream());
writer.write(urlParameters);
writer.flush();
String line;
BufferedReader reader = new BufferedReader(new InputStreamReader(
cox.getInputStream()));
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
writer.close();
reader.close();
} catch (Exception e) {
result = e.toString();
Sucess = false;
e.printStackTrace();
}

Neo4j - Server returned HTTP response code: 500 for URL: http://localhost:7474/db/data/cypher

I am getting below exception while running cypher using HTTPConnection.
Server returned HTTP response code: 500 for URL: http://localhost:7474/db/data/cypher
public class HTTPConnectionTest {
public static void main(String[] args) throws Exception {
try {
System.out.println("Testing HTTPConnection");
StringBuffer responseString = new StringBuffer();
String url = "http://localhost:7474/db/data/cypher";
//String query = "match (user:USER{id:\'Sree\'}) return user ";
String query = "match (user:USER{id:\"Sree\"}) return user ";
URL neo4jUrl = new URL(url);
HttpURLConnection httpConn = (HttpURLConnection) neo4jUrl
.openConnection();
httpConn.setRequestMethod("POST");
httpConn.setDoOutput(true);
httpConn.setDoInput(true);
httpConn.setRequestProperty("Content-Type", "application/json");
String urlParameters = "{\"query\":\"" + query + "\"}";
httpConn.setRequestProperty("Accept",
"application/json; charset=UTF-8");
DataOutputStream wr = new DataOutputStream(
httpConn.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
BufferedReader in = new BufferedReader(new InputStreamReader(
httpConn.getInputStream()));
String inputLine;
while ((inputLine = in.readLine()) != null) {
responseString.append(inputLine);
}
System.out.println("Out put " + responseString);
in.close();
} catch (Exception e) {
System.out.println("Exception" + e.getMessage());
}
}
}
If I pass value in cypher with single quotes it is working and getting output object.
String query = "match (user:USER{id:\'Sree\'}) return user ";
Any suggestions? Thank you in advance!
This looks silly to me.
a small change in code. Converted params into JSONObject string
JSONObject jsonObject = new JSONObject();
jsonObject.put("query", query);
String urlParameters = jsonObject.toString();
instead of
String urlParameters = "{\"query\":\"" + query + "\"}";

How to set parameters in a GET request in Java

So I want to send a GET request with parameters. But it only seems to have conventions for the url you send the request to. Unlike the POST request, I see no way to pass parameters in it.
How I send the GET request now, without parameters (might be wrong):
String url = "http://api.netatmo.net/api/getuser";
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
// optional default is GET
con.setRequestMethod("GET");
//add request header
con.setRequestProperty("User-Agent", USER_AGENT);
int responseCode = con.getResponseCode();
Log.v(TAG, ("\nSending 'GET' request to URL : " + url));
Log.v(TAG, ("Response Code : " + responseCode));
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
Log.v(TAG, (response.toString()));
How I send the POST request with parameters:
String url = "https://api.netatmo.net/oauth2/token";
URL obj = new URL(url);
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();
//add request header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
String urlParameters = "grant_type=password&client_id=myid&client_secret=mysecret&username=myusername&password=mypass";
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
Log.v(TAG, "\nSending 'POST' request to URL : " + url);
Log.v(TAG, "Post parameters : " + urlParameters);
Log.v(TAG, "Response Code : " + responseCode);
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
Log.v(TAG, response.toString());
access_token = response.substring(17, 74);
refresh_token = response.substring(93,150);
getRequest = "/api/getuser?access_token=" + access_token + " HTTP/1.1";
Log.v(TAG, access_token);
Log.v(TAG, refresh_token);
Log.v(TAG, getRequest);
As per the HTTP specification GET supports only path params or url params and hence you cannot put the params in HTTP request body as you do in POST request.
As Sotirios mentioned in the comments, technically you can still push params in the GET body, but if the APIs are respecting the specs, they will not provide you a way to do it.
Have you tried to add the query params to the request java.net.URL?
String url = "http://api.netatmo.net/api/getuser?access_token=" + access_token;
URL obj = new URL(url);
I was encountering the same problem, trying this:
String bla = "http://api.netatmo.net/api/devicelist?access_token=" + AUTH_TOKEN;
URL url = new URL(bla);
BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream()));
String line = "";
String message = "";
while ((line = reader.readLine()) != null)
{
message += line;
}
I got an exception that the syntax was not correct. When I changed the syntax (by for example encoding with UTF 8) the API would just return errors (like 404 not found...).
I finally got it working using this:
try
{
System.out.println("Access Token: " + AUTH_TOKEN);
String url = "http://api.netatmo.net/api/devicelist";
String query = "access_token=" + URLEncoder.encode(AUTH_TOKEN, CHARSET);
URLConnection connection = new URL(url + "?" + query).openConnection();
connection.setRequestProperty("Accept-Charset", CHARSET);
InputStream response = connection.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(response));
String line = "";
String message = "";
while ((line = reader.readLine()) != null)
{
message += line;
}
return message;
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Note: CHARSET = "UTF-8"
Turns out the url the API provided confused me greatly. I fixed the url and it works now.

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