use http connection pooling to improve performance (especially over ssl)

src/org/envaya/kalsms/App.java

@@ -18,12 +18,23 @@ import android.text.SpannableStringBuilder;
 import android.util.Log;
 import java.text.DateFormat;
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import org.apache.http.client.HttpClient;
+import org.apache.http.conn.params.ConnManagerParams;
+import org.apache.http.conn.scheme.PlainSocketFactory;
+import org.apache.http.conn.scheme.Scheme;
+import org.apache.http.conn.scheme.SchemeRegistry;
+import org.apache.http.conn.ssl.SSLSocketFactory;
+import org.apache.http.impl.client.DefaultHttpClient;
+import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
 import org.apache.http.message.BasicNameValuePair;
+import org.apache.http.params.BasicHttpParams;
+import org.apache.http.params.HttpConnectionParams;
+import org.apache.http.params.HttpParams;
+import org.apache.http.params.HttpProtocolParams;
 import org.envaya.kalsms.receiver.OutgoingMessagePoller;
 import org.envaya.kalsms.task.HttpTask;
 import org.envaya.kalsms.task.PollerTask;
@@ -85,8 +96,14 @@ public final class App extends Application {
     private SpannableStringBuilder displayedLog = new SpannableStringBuilder();
     private long lastLogTime;    
     
+    // list of package names (e.g. org.envaya.kalsms, or org.envaya.kalsms.packXX)
+    // for this package and all expansion packs
     private List<String> outgoingMessagePackages = new ArrayList<String>();
+    
+    // count to provide round-robin selection of expansion packs
     private int outgoingMessageCount = -1;
+    
+    // map of package name => sorted list of timestamps of outgoing messages
     private HashMap<String, ArrayList<Long>> outgoingTimestamps
             = new HashMap<String, ArrayList<Long>>();
         
@@ -147,6 +164,7 @@ public final class App extends Application {
             }                
             
             ArrayList<Long> sent = outgoingTimestamps.get(packageName);        
+            
             Long ct = System.currentTimeMillis();
 
             //log(packageName + " SMS send size=" + sent.size());
@@ -600,4 +618,33 @@ public final class App extends Application {
         }        
         return false;
     }    
+    
+    private HttpClient httpClient;
+    
+    public synchronized HttpClient getHttpClient()
+    {
+        if (httpClient == null)
+        {
+            // via http://thinkandroid.wordpress.com/2009/12/31/creating-an-http-client-example/
+            // also http://hc.apache.org/httpclient-3.x/threading.html
+            
+            HttpParams httpParams = new BasicHttpParams();
+            HttpConnectionParams.setConnectionTimeout(httpParams, 8000);
+            HttpConnectionParams.setSoTimeout(httpParams, 8000);                    
+            HttpProtocolParams.setContentCharset(httpParams, "utf-8");            
+            
+            SchemeRegistry registry = new SchemeRegistry();
+            registry.register(new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
+            
+            final SSLSocketFactory sslSocketFactory = SSLSocketFactory.getSocketFactory();            
+            sslSocketFactory.setHostnameVerifier(SSLSocketFactory.BROWSER_COMPATIBLE_HOSTNAME_VERIFIER);
+            
+            registry.register(new Scheme("https", sslSocketFactory, 443));
+
+            ThreadSafeClientConnManager manager = new ThreadSafeClientConnManager(httpParams, registry);            
+            
+            httpClient = new DefaultHttpClient(manager, httpParams);        
+        }
+        return httpClient;
+    }      
 }

src/org/envaya/kalsms/task/HttpTask.java

@@ -14,9 +14,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.Comparator;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
@@ -25,15 +23,10 @@ import org.apache.http.client.HttpClient;
 import org.apache.http.client.entity.UrlEncodedFormEntity;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.entity.mime.FormBodyPart;
-import org.apache.http.entity.mime.HttpMultipartMode;
 import org.apache.http.entity.mime.MultipartEntity;
-import org.apache.http.entity.mime.content.ContentBody;
 import org.apache.http.entity.mime.content.StringBody;
-import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.message.BasicNameValuePair;
-import org.apache.http.params.BasicHttpParams;
+import org.apache.http.util.EntityUtils;
-import org.apache.http.params.HttpConnectionParams;
-import org.apache.http.params.HttpParams;
 import org.envaya.kalsms.App;
 import org.envaya.kalsms.Base64Coder;
 import org.envaya.kalsms.OutgoingMessage;
@@ -53,6 +46,8 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
     private List<FormBodyPart> formParts;
     private boolean useMultipartPost = false;    
     
+    private HttpPost post;
+    
     public HttpTask(App app, BasicNameValuePair... paramsArr)
     {
         super();
@@ -69,14 +64,6 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
         this.formParts = formParts;
     }                  
     
-    public HttpClient getHttpClient()
-    {
-        HttpParams httpParameters = new BasicHttpParams();
-        HttpConnectionParams.setConnectionTimeout(httpParameters, 8000);
-        HttpConnectionParams.setSoTimeout(httpParameters, 8000);                    
-        return new DefaultHttpClient(httpParameters);        
-    }            
-    
     private String getSignature()
             throws NoSuchAlgorithmException, UnsupportedEncodingException
     {
@@ -110,16 +97,15 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
     }    
     
     protected HttpResponse doInBackground(String... ignored) {
+        if (url.length() == 0) {
+            app.log("Can't contact server; Server URL not set");                        
+            return null;
+        }
+
+        post = new HttpPost(url);        
+        
         try
         {              
-            if (url.length() == 0) {
-                app.log("Can't contact server; Server URL not set");                        
-                return null;
-            }            
-            
-            HttpPost post = new HttpPost(url);
-            
-     
             if (useMultipartPost)
             {
                 MultipartEntity entity = new MultipartEntity();//HttpMultipartMode.BROWSER_COMPATIBLE);
@@ -144,7 +130,7 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
             
             post.setHeader("X-Kalsms-Signature", signature);
             
-            HttpClient client = getHttpClient();
+            HttpClient client = app.getHttpClient();
             HttpResponse response = client.execute(post);            
 
             int statusCode = response.getStatusLine().getStatusCode();
@@ -154,27 +140,30 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
             } 
             else if (statusCode == 403)
             {
+                response.getEntity().consumeContent();
                 app.log("Failed to authenticate to server");
                 app.log("(Phone number or password may be incorrect)");                
                 return null;
             }
             else 
             {
+                response.getEntity().consumeContent();
                 app.log("Received HTTP " + statusCode + " from server");
                 return null;
             }            
         } 
         catch (IOException ex) 
         {
+            post.abort();
             app.logError("Error while contacting server", ex);
             return null;
         }
         catch (Throwable ex) 
         {
+            post.abort();
             app.logError("Unexpected error while contacting server", ex, true);
             return null;
         }        
-        
     }
     
     protected String getDefaultToAddress()
@@ -224,6 +213,7 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
             }
             catch (Throwable ex)
             {
+                post.abort();
                 app.logError("Error processing server response", ex);
                 handleFailure();
             }
@@ -236,6 +226,10 @@ public class HttpTask extends AsyncTask<String, Void, HttpResponse> {
     
     protected void handleResponse(HttpResponse response) throws Exception
     {
+        if (response != null)
+        {
+            response.getEntity().consumeContent();
+        }
     }    
     
     protected void handleFailure()