BigInteger arithmetic is slow as hell. Cache getFirst/Last address

2 files changed, 9 insertions, 3 deletions

diff --git a/main/src/main/java/de/blinkt/openvpn/core/NetworkSpace.java b/main/src/main/java/de/blinkt/openvpn/core/NetworkSpace.java
index c7d09065..54470962 100644
--- a/main/src/main/java/de/blinkt/openvpn/core/NetworkSpace.java
+++ b/main/src/main/java/de/blinkt/openvpn/core/NetworkSpace.java
@@ -15,6 +15,8 @@ public class NetworkSpace {
         public int networkMask;
         private boolean included;
         private boolean isV4;
+        private BigInteger firstaddr;
+        private BigInteger lastaddr;
 
 
         @Override
@@ -55,12 +57,16 @@ public class NetworkSpace {
         }
 
         public BigInteger getLastAddress() {
-            return getMaskedAddress(true);
+            if(lastaddr==null)
+                lastaddr= getMaskedAddress(true);
+            return lastaddr;
         }
 
 
         public BigInteger getFirstAddress() {
-            return getMaskedAddress(false);
+            if (firstaddr==null)
+                firstaddr=getMaskedAddress(false);
+            return firstaddr;
         }
 
 
diff --git a/main/src/main/res/values/strings.xml b/main/src/main/res/values/strings.xml
index 8c643f6d..3b9b9c0f 100755
--- a/main/src/main/res/values/strings.xml
+++ b/main/src/main/res/values/strings.xml
@@ -220,7 +220,7 @@
     <string name="openvpn_log">OpenVPN Log</string>
     <string name="import_config">Import OpenVPN configuration</string>
     <string name="battery_consumption_title">Battery consumption</string>
-    <string name="baterry_consumption">In my personal tests the main reason for high battery consumption of OpenVPN are the keepalive packets. Most OpenVPN servers have a configuration directive like \'keepalive 10 60\' which causes the client and server to exchange keepalive packets every ten seconds. &lt;p&gt; While these packets are small and do not use much traffic, they keep the mobile radio network busy and increase the energy consumption. (See also &lt;a href="http://developer.android.com/training/efficient-downloads/efficient-network-access.html#RadioStateMachine"&gt;The Radio State Machine | Android Developers&lt;/a&gt;) &lt;p&gt; This keepalive setting cannot be changed on the client. Only the system administrator of the OpenVPN can change the setting. &lt;p&gt; Unfortunately using a keepalive larger than 60 seconds with UDP can cause some NAT gateways to drop the connection due to an inactivity timeout. Using TCP with a long keepalive timeout works, but tunneling TCP over TCP performs extremely poorly on connections with high packet loss. (See &lt;a href="http://sites.inka.de/bigred/devel/tcp-tcp.html"&gt;Why TCP Over TCP Is A Bad Idea&lt;/a&gt;)</string>
+    <string name="baterry_consumption">In my personal tests the main reason for high battery consumption of OpenVPN are the keepalive packets. Most OpenVPN servers have a configuration directive like \'keepalive 10 60\' which causes the client and server to exchange keepalive packets every ten seconds. &lt;p&gt; While these packets are small and do not use much traffic, they keep the mobile radio network busy and increase the energy consumption. (See also &lt;a href="http://developer.android.com/training/efficient-downloads/efficient-network-access.html#RadioStateMachine"&gt;The Radio State Machine | Android Developers&lt;/a&gt;) &lt;p&gt; This keepalive setting cannot be changed on the client. Only the system administrator of the OpenVPN can change the setting. &lt;p&gt; Unfortunately using a keepalive larger than 60 seconds with UDP can cause some NAT gateways to drop the connection due to an inactivity timeout. Using TCP with a long keep alive timeout works, but tunneling TCP over TCP performs extremely poorly on connections with high packet loss. (See &lt;a href="http://sites.inka.de/bigred/devel/tcp-tcp.html"&gt;Why TCP Over TCP Is A Bad Idea&lt;/a&gt;)</string>
     <string name="faq_tethering">The Android Tethering feature (over WiFi, USB or Bluetooth) and the VPNService API (used by this program) do not work together. For more details see the &lt;a href=\"http://code.google.com/p/ics-openvpn/issues/detail?id=34\">issue #34&lt;/a></string>
     <string name="vpn_tethering_title">VPN and Tethering</string>
     <string name="connection_retries">Connection retries</string>