Prevent multiple threads from initing http at once

app/src/main/java/org/transdroid/daemon/adapters/aria2c/Aria2Adapter.java

@@ -19,9 +19,7 @@ package org.transdroid.daemon.adapters.aria2c;
 
 import android.net.Uri;
 import android.text.TextUtils;
-
 import net.iharder.Base64;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpPost;
@@ -86,6 +84,14 @@ public class Aria2Adapter implements IDaemonAdapter {
         this.settings = settings;
     }
 
+    private synchronized void initialise() throws DaemonException {
+        if (httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, !TextUtils.isEmpty(settings.getUsername()));
+            httpclient.addRequestInterceptor(HttpHelper.gzipRequestInterceptor);
+            httpclient.addResponseInterceptor(HttpHelper.gzipResponseInterceptor);
+        }
+    }
+
     @Override
     public DaemonTaskResult executeTask(Log log, DaemonTask task) {
 
@@ -282,13 +288,8 @@ public class Aria2Adapter implements IDaemonAdapter {
     private synchronized String makeRawRequest(Log log, String data) throws DaemonException {
 
         try {
-
             // Initialise the HTTP client
-            if (httpclient == null) {
-                httpclient = HttpHelper.createStandardHttpClient(settings, !TextUtils.isEmpty(settings.getUsername()));
-                httpclient.addRequestInterceptor(HttpHelper.gzipRequestInterceptor);
-                httpclient.addResponseInterceptor(HttpHelper.gzipResponseInterceptor);
-            }
+            initialise();
 
             // Set POST URL and data
             String url =

app/src/main/java/org/transdroid/daemon/adapters/bitComet/BitCometAdapter.java

@@ -19,7 +19,6 @@ package org.transdroid.daemon.adapters.bitComet;
 
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.HttpStatus;
@@ -253,8 +252,10 @@ public class BitCometAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**
@@ -271,9 +272,7 @@ public class BitCometAdapter implements IDaemonAdapter {
         try {
 
             // Initialize the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Add the parameters to the query string
             boolean first = true;

app/src/main/java/org/transdroid/daemon/adapters/bitflu/BitfluAdapter.java

@@ -140,9 +140,7 @@ public class BitfluAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // TLog.d(LOG_NAME, "Request to: "+ buildWebUIUrl() + addToUrl);
 
@@ -268,9 +266,10 @@ public class BitfluAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/buffaloNas/BuffaloNasAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.buffaloNas;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.HttpStatus;
@@ -174,9 +173,7 @@ public class BuffaloNasAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Add the parameters to the query string
             boolean first = true;
@@ -251,9 +248,10 @@ public class BuffaloNasAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
 
     }
 

app/src/main/java/org/transdroid/daemon/adapters/dLinkRouterBT/DLinkRouterBTAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.dLinkRouterBT;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpPost;
@@ -234,9 +233,7 @@ public class DLinkRouterBTAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Setup request using POST stream with URL and data
             HttpPost httppost = new HttpPost(buildWebUIUrl() + requestUrl);
@@ -304,8 +301,10 @@ public class DLinkRouterBTAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/deluge/DelugeAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.deluge;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpGet;
@@ -163,9 +162,7 @@ public class DelugeAdapter implements IDaemonAdapter {
         log.d(LOG_NAME, "Uploading a file to the Deluge daemon: " + url);
 
         // Initialise the HTTP client
-        if (httpclient == null) {
-            initialise();
-        }
+        initialise();
 
         // Setup client using POST
         HttpPost httppost = new HttpPost(url);
@@ -437,9 +434,7 @@ public class DelugeAdapter implements IDaemonAdapter {
         // We still need to retrieve the version number from the server
         // Do this by getting the web interface main html page and trying to parse the version number
         // Format is something like '<title>Deluge: Web UI 1.3.6</title>'
-        if (httpclient == null) {
-            initialise();
-        }
+        initialise();
         try {
             HttpResponse response = httpclient.execute(new HttpGet(buildWebUIUrl() + "/"));
             String main = HttpHelper.convertStreamToString(response.getEntity().getContent());
@@ -478,9 +473,7 @@ public class DelugeAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Login first?
             if (sessionCookie == null) {
@@ -582,11 +575,11 @@ public class DelugeAdapter implements IDaemonAdapter {
      * @throws DaemonException On missing settings
      */
     private void initialise() throws DaemonException {
-
-        httpclient = HttpHelper.createStandardHttpClient(settings, settings.getUsername() != null && !settings.getUsername().equals(""));
-        httpclient.addRequestInterceptor(HttpHelper.gzipRequestInterceptor);
-        httpclient.addResponseInterceptor(HttpHelper.gzipResponseInterceptor);
-
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, settings.getUsername() != null && !settings.getUsername().equals(""));
+            httpclient.addRequestInterceptor(HttpHelper.gzipRequestInterceptor);
+            httpclient.addResponseInterceptor(HttpHelper.gzipResponseInterceptor);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/kTorrent/KTorrentAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.kTorrent;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpResponse;
 import org.apache.http.NameValuePair;
 import org.apache.http.ProtocolException;
@@ -464,12 +463,10 @@ public class KTorrentAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException Thrown on settings error
      */
-    private void initialise() throws DaemonException {
-
-        if (httpclient != null) {
-            httpclient = null;
+    private synchronized void initialise() throws DaemonException {
+        if (httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, false);
         }
-        httpclient = HttpHelper.createStandardHttpClient(settings, false);
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/qBittorrent/QBittorrentAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.qBittorrent;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.NameValuePair;
@@ -587,7 +586,7 @@ public class QBittorrentAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
+    private synchronized void initialise() throws DaemonException {
         if (httpclient == null) {
             httpclient = HttpHelper.createStandardHttpClient(settings, true);
         }

app/src/main/java/org/transdroid/daemon/adapters/rTorrent/RTorrentAdapter.java

@@ -18,7 +18,9 @@
 package org.transdroid.daemon.adapters.rTorrent;
 
 import android.text.TextUtils;
-
+import de.timroes.axmlrpc.XMLRPCClient;
+import de.timroes.axmlrpc.XMLRPCClient.UnauthorizdException;
+import de.timroes.axmlrpc.XMLRPCException;
 import org.transdroid.core.gui.log.Log;
 import org.transdroid.daemon.Daemon;
 import org.transdroid.daemon.DaemonException;
@@ -66,10 +68,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
 
-import de.timroes.axmlrpc.XMLRPCClient;
-import de.timroes.axmlrpc.XMLRPCClient.UnauthorizdException;
-import de.timroes.axmlrpc.XMLRPCException;
-
 /**
  * An adapter that allows for easy access to rTorrent torrent data. Communication is handled via the XML-RPC protocol as
  * implemented by the aXMLRPC library.
@@ -328,9 +326,7 @@ public class RTorrentAdapter implements IDaemonAdapter {
             throws DaemonException, MalformedURLException {
 
         // Initialise the HTTP client
-        if (rpcclient == null) {
-            initialise();
-        }
+        initialise();
 
         StringBuilder paramsBuilder = new StringBuilder();
         for (Object arg : arguments) {
@@ -365,14 +361,13 @@ public class RTorrentAdapter implements IDaemonAdapter {
      * Instantiates a XML-RPC client with proper credentials.
      *
      * @throws DaemonException       On conflicting settings (i.e. user authentication but no password or username provided)
-     * @throws MalformedURLException Thrown when the URL could not be properly constructed
      */
-    private void initialise() throws DaemonException, MalformedURLException {
-
-        int flags = XMLRPCClient.FLAGS_8BYTE_INT;
-        this.rpcclient = new XMLRPCClient(HttpHelper.createStandardHttpClient(settings, true),
-                settings.getAddress(), buildWebUIUrl(), flags);
-
+    private synchronized void initialise() throws DaemonException {
+        if(rpcclient == null) {
+            int flags = XMLRPCClient.FLAGS_8BYTE_INT;
+            this.rpcclient = new XMLRPCClient(HttpHelper.createStandardHttpClient(settings, true),
+                    settings.getAddress(), buildWebUIUrl(), flags);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/synology/SynologyAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.synology;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpGet;
@@ -84,10 +83,17 @@ public class SynologyAdapter implements IDaemonAdapter {
         this.settings = settings;
     }
 
+    private synchronized void initialise() throws DaemonException {
+        if (httpClient == null) {
+            httpClient = HttpHelper.createStandardHttpClient(settings, true);
+        }
+    }
+
     @Override
     public DaemonTaskResult executeTask(Log log, DaemonTask task) {
         String tid;
         try {
+            initialise();
             switch (task.getMethod()) {
                 case Retrieve:
                     return new RetrieveTaskSuccessResult((RetrieveTask) task, tasksList(log), null);
@@ -425,13 +431,6 @@ public class SynologyAdapter implements IDaemonAdapter {
         return new SynoRequest(path, api, version).post(sid, params);
     }
 
-    private DefaultHttpClient getHttpClient() throws DaemonException {
-        if (httpClient == null) {
-            httpClient = HttpHelper.createStandardHttpClient(settings, true);
-        }
-        return httpClient;
-    }
-
     private static class SynoResponse {
 
         private final HttpResponse response;
@@ -502,7 +501,7 @@ public class SynologyAdapter implements IDaemonAdapter {
 
         public SynoResponse get(String params) throws DaemonException {
             try {
-                return new SynoResponse(getHttpClient().execute(new HttpGet(buildURL(params))));
+                return new SynoResponse(httpClient.execute(new HttpGet(buildURL(params))));
             } catch (IOException e) {
                 throw new DaemonException(ExceptionType.ConnectionError, e.toString());
             }
@@ -523,7 +522,7 @@ public class SynologyAdapter implements IDaemonAdapter {
                 System.arraycopy(params, 0, allParams, baseParams.length, params.length);
 
                 request.setEntity(new MultipartEntity(allParams));
-                return new SynoResponse(getHttpClient().execute(request));
+                return new SynoResponse(httpClient.execute(request));
             } catch (IOException e) {
                 throw new DaemonException(ExceptionType.ConnectionError, e.toString());
             }

app/src/main/java/org/transdroid/daemon/adapters/tTorrent/TTorrentAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.tTorrent;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.NameValuePair;
@@ -233,9 +232,7 @@ public class TTorrentAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Execute
             HttpResponse response = httpclient.execute(httppost);
@@ -267,8 +264,10 @@ public class TTorrentAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/tfb4rt/Tfb4rtAdapter.java

@@ -20,7 +20,6 @@ package org.transdroid.daemon.adapters.tfb4rt;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpGet;
 import org.apache.http.client.methods.HttpPost;
@@ -176,9 +175,7 @@ public class Tfb4rtAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Make request
             HttpGet httpget = new HttpGet(buildWebUIUrl(RPC_URL_STATS));
@@ -205,9 +202,7 @@ public class Tfb4rtAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Make request
             HttpGet httpget = new HttpGet(buildWebUIUrl(RPC_URL_DISPATCH + action + RPC_URL_DISPATCH2 + RPC_URL_AID
@@ -239,9 +234,7 @@ public class Tfb4rtAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
 
             // Make request
             HttpPost httppost = new HttpPost(buildWebUIUrl(RPC_URL_DISPATCH + action + RPC_URL_DISPATCH2 + RPC_URL_AID));
@@ -276,8 +269,10 @@ public class Tfb4rtAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/transmission/TransmissionAdapter.java

@@ -19,7 +19,6 @@ package org.transdroid.daemon.adapters.transmission;
 
 import net.iharder.Base64;
 import net.iharder.Base64.InputStream;
-
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpResponse;
 import org.apache.http.client.methods.HttpPost;
@@ -403,9 +402,7 @@ public class TransmissionAdapter implements IDaemonAdapter {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
+            initialise();
             final String sessionHeader = "X-Transmission-Session-Id";
 
             // Setup request using POST stream with URL and data
@@ -477,8 +474,10 @@ public class TransmissionAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        httpclient = HttpHelper.createStandardHttpClient(settings, true);
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
+        }
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/uTorrent/UTorrentAdapter.java

@@ -20,12 +20,9 @@ package org.transdroid.daemon.adapters.uTorrent;
 import com.android.internal.http.multipart.FilePart;
 import com.android.internal.http.multipart.MultipartEntity;
 import com.android.internal.http.multipart.Part;
-
 import org.apache.http.HttpResponse;
-import org.apache.http.client.CookieStore;
 import org.apache.http.client.methods.HttpGet;
 import org.apache.http.client.methods.HttpPost;
-import org.apache.http.impl.client.BasicCookieStore;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.json.JSONArray;
 import org.json.JSONException;
@@ -117,12 +114,10 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
     private static final int RPC_FILESIZE_IDX = 1;
     private static final int RPC_FILEDOWNLOADED_IDX = 2;
     private static final int RPC_FILEPRIORITY_IDX = 3;
-    private static String authtoken;
+    private String authtoken;
     private static ArrayList<RemoteRssChannel> remoteRssChannels = new ArrayList<>();
     private DaemonSettings settings;
     private DefaultHttpClient httpclient;
-    private static CookieStore cookieStore;
-
 
     /**
      * Initialises an adapter that provides operations to the uTorrent web daemon
@@ -368,11 +363,8 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
         try {
 
             // Initialise the HTTP client
-            if (httpclient == null) {
-                initialise();
-            }
-
-            ensureToken();
+            initialise();
+            ensureToken(retried > 0);
 
             // Make request
             HttpGet httpget = new HttpGet(buildWebUIUrl() + "?token=" + authtoken + addToUrl);
@@ -383,7 +375,6 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
             String result = HttpHelper.convertStreamToString(instream);
             if ((result.equals("") || result.trim().equals("invalid request"))) {
                 // Auth token was invalidated; retry at max 3 times
-                authtoken = null; // So that ensureToken() will request a new token on the next try
                 if (retried < 2) {
                     return makeUtorrentRequest(log, addToUrl, ++retried);
                 }
@@ -407,10 +398,10 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
 
     }
 
-    private synchronized void ensureToken() throws IOException, DaemonException {
+    private synchronized void ensureToken(boolean forceReload) throws IOException, DaemonException {
 
-        // Make sure we have a valid token
-        if (authtoken == null) {
+        // Make sure we have a valid token or we're regenerating it
+        if (authtoken == null || forceReload) {
 
             // Make a request to /gui/token.html
             // See https://github.com/bittorrent/webui/wiki/TokenSystem
@@ -437,11 +428,8 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
     public JSONObject uploadTorrentFile(String file) throws DaemonException, IOException, JSONException {
 
         // Initialise the HTTP client
-        if (httpclient == null) {
-            initialise();
-        }
-
-        ensureToken();
+        initialise();
+        ensureToken(false);
 
         // Build and make request
         HttpPost httppost = new HttpPost(buildWebUIUrl() + "?token=" + authtoken + "&action=add-file");
@@ -464,13 +452,10 @@ public class UTorrentAdapter implements IDaemonAdapter, RemoteRssSupplier {
      *
      * @throws DaemonException On conflicting or missing settings
      */
-    private void initialise() throws DaemonException {
-        if (this.cookieStore == null) {
-            this.cookieStore = new BasicCookieStore();
+    private synchronized void initialise() throws DaemonException {
+        if(httpclient == null) {
+            httpclient = HttpHelper.createStandardHttpClient(settings, true);
         }
-
-        this.httpclient = HttpHelper.createStandardHttpClient(settings, true);
-        this.httpclient.setCookieStore(this.cookieStore);
     }
 
     /**

app/src/main/java/org/transdroid/daemon/adapters/vuze/VuzeAdapter.java

@@ -226,9 +226,7 @@ public class VuzeAdapter implements IDaemonAdapter {
         // TODO: It would be nicer to now split each of these steps into separate makeVuzeCalls when there are multiple logical steps such as stopping a torrent before removing it
 
         // Initialise the HTTP client
-        if (rpcclient == null) {
-            initialise();
-        }
+        initialise();
         if (settings.getAddress() == null || settings.getAddress().equals("")) {
             throw new DaemonException(DaemonException.ExceptionType.AuthenticationFailure, "No host name specified.");
         }
@@ -329,10 +327,10 @@ public class VuzeAdapter implements IDaemonAdapter {
      *
      * @throws DaemonException On conflicting settings (i.e. user authentication but no password or username provided)
      */
-    private void initialise() throws DaemonException {
-
-        this.rpcclient = new VuzeXmlOverHttpClient(settings, buildWebUIUrl());
-
+    private synchronized void initialise() throws DaemonException {
+        if(rpcclient == null) {
+            rpcclient = new VuzeXmlOverHttpClient(settings, buildWebUIUrl());
+        }
     }
 
     /**