svn commit: r903845 - in /incubator/cassandra/trunk: conf/storage-conf.xml src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java src/java/org/apache/cassandra/locator/EndPointSnitch.java

[jb...@apache.org]

Author: jbellis
Date: Wed Jan 27 21:18:32 2010
New Revision: 903845

URL: http://svn.apache.org/viewvc?rev=903845&view=rev
Log:
update endpoint snitch comments.  patch by jbellis

Modified:
    incubator/cassandra/trunk/conf/storage-conf.xml
    incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java
    incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java

Modified: incubator/cassandra/trunk/conf/storage-conf.xml
URL: http://svn.apache.org/viewvc/incubator/cassandra/trunk/conf/storage-conf.xml?rev=903845&r1=903844&r2=903845&view=diff
==============================================================================
--- incubator/cassandra/trunk/conf/storage-conf.xml (original)
+++ incubator/cassandra/trunk/conf/storage-conf.xml Wed Jan 27 21:18:32 2010
@@ -158,9 +158,10 @@
 
   <!--
    ~ EndPointSnitch: Setting this to the class that implements
-   ~ IEndPointSnitch which will see if two endpoints are in the same data
-   ~ center or on the same rack. Out of the box, Cassandra provides
-   ~ org.apache.cassandra.locator.EndPointSnitch
+   ~ AbstractEndpointSnitch, which lets Cassandra know enough
+   ~ about your network topology to route requests efficiently.
+   ~ Out of the box, Cassandra provides org.apache.cassandra.locator.EndPointSnitch,
+   ~ and PropertyFileEndPointSnitch is available in contrib/.
   -->
   <EndPointSnitch>org.apache.cassandra.locator.EndPointSnitch</EndPointSnitch>
 

Modified: incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java
URL: http://svn.apache.org/viewvc/incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java?rev=903845&r1=903844&r2=903845&view=diff
==============================================================================
--- incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java (original)
+++ incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/AbstractEndpointSnitch.java Wed Jan 27 21:18:32 2010
@@ -25,10 +25,15 @@
 import java.net.UnknownHostException;
 import java.util.*;
 
+/**
+ * An endpoint snitch tells Cassandra information about network topology that it can use to route
+ * requests more efficiently (with "sortByProximity").  Of the abstract methods, isOnSameRack
+ * and isInSameDataCenter are always required; getLocation is only used by DatacenterShardStrategy.
+ */
 public abstract class AbstractEndpointSnitch implements IEndPointSnitch
 {
     /**
-     * Helps determine if 2 nodes are in the same rack in the data center.
+     * Determines if 2 nodes are in the same rack in the data center.
      * @param host a specified endpoint
      * @param host2 another specified endpoint
      * @return true if on the same rack false otherwise
@@ -37,7 +42,7 @@
     abstract public boolean isOnSameRack(InetAddress host, InetAddress host2) throws UnknownHostException;
 
     /**
-     * Helps determine if 2 nodes are in the same data center.
+     * Determines if 2 nodes are in the same data center.
      * @param host a specified endpoint
      * @param host2 another specified endpoint
      * @return true if in the same data center false otherwise
@@ -46,7 +51,9 @@
     abstract public boolean isInSameDataCenter(InetAddress host, InetAddress host2) throws UnknownHostException;
 
     /**
-     * Given endpoints this method will help us know the datacenter name where the node is located at.
+     * Determines the name of the datacenter this endpoint lives in.
+     * @param endpoint
+     * @return the name of the datacenter the endpoint lives in
      */
     abstract public String getLocation(InetAddress endpoint) throws UnknownHostException;
 

Modified: incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java
URL: http://svn.apache.org/viewvc/incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java?rev=903845&r1=903844&r2=903845&view=diff
==============================================================================
--- incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java (original)
+++ incubator/cassandra/trunk/src/java/org/apache/cassandra/locator/EndPointSnitch.java Wed Jan 27 21:18:32 2010
@@ -22,6 +22,10 @@
 import java.net.UnknownHostException;
 import java.util.*;
 
+/**
+ * A simple endpoint snitch implementation that assumes rack and dc information is encoded
+ * in the ip address.
+ */
 public class EndPointSnitch extends AbstractEndpointSnitch
 {
     public boolean isOnSameRack(InetAddress host, InetAddress host2) throws UnknownHostException