ProtocolException: unexpected end of stream
<p>I've been dealing with an issue that keeps coming back and I'm getting quite frustrated. I'm trying to connect to my database via a template php webservice that I found online, by sending it JSONObjects. I keep getting either an IOException or ProtocolException when trying to get a response code from the server with the cause being "Unexpected end of stream". The error message is really cryptic and I have no idea is the error is in the java or the PHP code. I posted the code, so you can take a look:</p>

<p>Stack trace:
<div class="snippet" data-lang="js" data-hide="false">
<div class="snippet-code">
<pre class="snippet-code-css lang-css prettyprint-override"><code>java.net.ProtocolException: unexpected end of stream
     at com.android.okhttp.internal.http.HttpConnection$FixedLengthSink.close(HttpConnection.java:314)
     at com.android.okhttp.internal.http.HttpEngine.readResponse(HttpEngine.java:781)
     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:443)
     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:388)
     at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:501)
     at ske.matej.project.JSONParser.getJSONFromUrl(JSONParser.java:56)
     at ske.matej.project.UserFunctions.loginUser(UserFunctions.java:35)
     at ske.matej.project.LoginActivity$AttemptLogin.doInBackground(LoginActivity.java:145)
     at ske.matej.project.LoginActivity$AttemptLogin.doInBackground(LoginActivity.java:121)
     at android.os.AsyncTask$2.call(AsyncTask.java:295)
     at java.util.concurrent.FutureTask.run(FutureTask.java:237)
     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
     at java.lang.Thread.run(Thread.java:818)</code></pre>
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</p>

<p>JSONParser.java (I marked the offending line with a comment)</p>

<pre class="lang-java prettyprint-override"><code>import android.util.Log;

import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;


public class JSONParser {

    private JSONObject jsonObj = new JSONObject();
    private JSONObject json = new JSONObject();
    private String email;
    private String username;
    private String password;
    private int objLength;
    private static InputStream is = null;

    public JSONParser() {
        //Default constructor intentionally left empty for now
    }

    public JSONObject getJSONFromUrl(String _url, JSONObject params) {

        // Making HTTP request
        try {
            URL url = new URL(_url);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();

            byte[] bytearray = params.toString().getBytes("UTF-8");

            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setRequestMethod("POST");
            conn.setFixedLengthStreamingMode(bytearray.length);
            //conn.setRequestProperty("User-Agent", "GYUserAgentAndroid");
            conn.setRequestProperty("Content-Length", Integer.toString(bytearray.length));
            conn.setRequestProperty("Content-Type", "application/json");
            //conn.setUseCaches(false);

            System.out.println("Byte array length: "+bytearray.length);

            //The offending line                
            int responseCodeHTTP = conn.getResponseCode(); 

            System.out.println("Responsecode HTTP "+responseCodeHTTP);

            OutputStream os = conn.getOutputStream();
            os.write(bytearray);
            os.flush();

            if (responseCodeHTTP == HttpURLConnection.HTTP_OK) {
                try {
                    is = new BufferedInputStream(conn.getInputStream());
                    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);
                    }
                    is.close();
                    json = new JSONObject(sb.toString());
                    Log.e("JSON", json.toString());
                }
                catch (JSONException e) {
                    e.printStackTrace();
                }
            }

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return json;

    }

    public byte[] getJSONBytes() {
        try {
            return jsonObj.toString().getBytes("UTF-8");
        }
        catch(UnsupportedEncodingException e) {
            e.printStackTrace();
            return null;
        }
    }
}
</code></pre>

<p>index.php (I didn't change much in the code yet, just want to establish a connection for now)</p>

<p><div class="snippet" data-lang="js" data-hide="false">
<div class="snippet-code">
<pre class="snippet-code-css lang-css prettyprint-override"><code>&lt;?php
 
if($_POST != null) {
 
 echo json_encode("Status: 200");
 
 if (isset($_POST['tag']) &amp;&amp; $_POST['tag'] != '') {
    // Get tag
    $tag = $_POST['tag'];
 
    // Include Database handler
    require_once 'DB_Functions.php';
    $db = new DB_Functions();
    // response Array
    $response = array("tag" =&gt; $tag, "success" =&gt; 0, "error" =&gt; 0);
 
    // check for tag type
    if ($tag == 'login') {
        // Request type is check Login
        $email = $_POST['email'];
        $password = $_POST['password'];
 
        // check for user
        $user = $db-&gt;getUserByEmailAndPassword($email, $password);
  
  
  //FOR TESTING PURPOSES: REMOVE LATER
  $user = false;
  
  
        if ($user != false) {
            // user found
            // echo json with success = 1
            $response["success"] = 1;
            $response["user"]["fname"] = $user["firstname"];
            $response["user"]["lname"] = $user["lastname"];
            $response["user"]["email"] = $user["email"];
        $response["user"]["uname"] = $user["username"];
            $response["user"]["uid"] = $user["unique_id"];
            $response["user"]["created_at"] = $user["created_at"];
 
            echo json_encode($response);
        } else {
            // user not found
            // echo json with error = 1
            $response["error"] = 1;
            $response["error_msg"] = "Incorrect email or password!";
            echo json_encode($response);
        }
    }
  else if ($tag == 'chgpass'){
  $email = $_POST['email'];
 
  $newpassword = $_POST['newpas'];
 
  $hash = $db-&gt;hashSSHA($newpassword);
        $encrypted_password = $hash["encrypted"]; // encrypted password
        $salt = $hash["salt"];
  $subject = "Change Password Notification";
         $message = "Hello User,nnYour Password is sucessfully changed.nnRegards,nLearn2Crack Team.";
          $from = "contact@learn2crack.com";
          $headers = "From:" . $from;
    if ($db-&gt;isUserExisted($email)) {
 
 $user = $db-&gt;forgotPassword($email, $encrypted_password, $salt);
if ($user) {
         $response["success"] = 1;
          mail($email,$subject,$message,$headers);
         echo json_encode($response);
}
else {
$response["error"] = 1;
echo json_encode($response);
}
 
            // user is already existed - error response
 
        }
           else {
 
            $response["error"] = 2;
            $response["error_msg"] = "User not exist";
             echo json_encode($response);
 
}
}
else if ($tag == 'forpass'){
$forgotpassword = $_POST['forgotpassword'];
 
$randomcode = $db-&gt;random_string();
 
$hash = $db-&gt;hashSSHA($randomcode);
        $encrypted_password = $hash["encrypted"]; // encrypted password
        $salt = $hash["salt"];
  $subject = "Password Recovery";
         $message = "Hello User,nnYour Password is sucessfully changed. Your new Password is $randomcode . Login with your new Password and change it in the User Panel.nnRegards,nLearn2Crack Team.";
          $from = "contact@learn2crack.com";
          $headers = "From:" . $from;
    if ($db-&gt;isUserExisted($forgotpassword)) {
 
 $user = $db-&gt;forgotPassword($forgotpassword, $encrypted_password, $salt);
if ($user) {
         $response["success"] = 1;
          mail($forgotpassword,$subject,$message,$headers);
         echo json_encode($response);
}
else {
$response["error"] = 1;
echo json_encode($response);
}
 
            // user is already existed - error response
 
        }
           else {
 
            $response["error"] = 2;
            $response["error_msg"] = "User not exist";
             echo json_encode($response);
 
}
 
}
else if ($tag == 'register') {
        // Request type is Register new user
        $fname = $_POST['fname'];
        $lname = $_POST['lname'];
        $email = $_POST['email'];
        $uname = $_POST['uname'];
        $password = $_POST['password'];
 
        // check if user is already existed
        if ($db-&gt;isUserExisted($email)) {
            // user is already existed - error response
            $response["error"] = 2;
            $response["error_msg"] = "User already existed";
            echo json_encode($response);
        }
           else if(!$db-&gt;validEmail($email)){
            $response["error"] = 3;
            $response["error_msg"] = "Invalid Email Id";
            echo json_encode($response);
}
else {
            // store user
            $user = $db-&gt;storeUser($fname, $lname, $email, $uname, $password);
            if ($user) {
                // user stored successfully
            $response["success"] = 1;
            $response["user"]["fname"] = $user["firstname"];
            $response["user"]["lname"] = $user["lastname"];
            $response["user"]["email"] = $user["email"];
        $response["user"]["uname"] = $user["username"];
            $response["user"]["uid"] = $user["unique_id"];
            $response["user"]["created_at"] = $user["created_at"];
               mail($email,$subject,$message,$headers);
 
                echo json_encode($response);
            } else {
                // user failed to store
                $response["error"] = 1;
                $response["error_msg"] = "JSON Error occured in Registartion";
                echo json_encode($response);
            }
        }
    } else {
         $response["error"] = 3;
         $response["error_msg"] = "JSON ERROR";
        echo json_encode($response);
    }
} else {
    echo "";
}
}
 
?&gt;</code></pre>
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</p>

<p>I really appreciate any help you can give. Especially because I'm still a noob in Android development and PHP.</p>