com.basho.riak.client.api.commands.kv

Class UpdateValue

java.lang.Object

com.basho.riak.client.api.RiakCommand<UpdateValue.Response,Location>

com.basho.riak.client.api.commands.kv.UpdateValue

public final class UpdateValue
extends RiakCommand<UpdateValue.Response,Location>

Perform an full cycle update of a Riak value: fetch, resolve, modify, store.

The UpdateValue command completely encapsulates the typical read/modify/write cycle used with data in Riak.

The object specified by the given Location will be fetched from Riak and have the ConflictResolver stored in the ConflictResolverFactory applied. The resolved object is then passed to your UpdateValue.Update and the result stored back into Riak.

To create the mutation you wish to perform, you extend the UpdateValue.Update class:

 class AppendUpdate extends UpdateValue.Update<MyPojo>
 {
     private final String update;

     public AppendUpdate(String update)
     {
         this.update = update;
     }

     {@literal @Override}
     public MyPojo apply(MyPojo original)
     {
         if (original == null)
         {
             original = new MyPojo();
         }

         original.value += update;
         return original;
     }
 }

 Namespace ns = new Namespace("my_type", "my_bucket");
 Location loc = new Location(ns, "my_key");
 AppendUpdate update = new AppendUpdate("append this string");

 UpdateValue uv =
     new UpdateValue.Builder(loc).withUpdate(update).build();

 UpdateValue.Response response = client.execute(uv);

Since:

2.0

Author:

Dave Rusek

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UpdateValue.Builder Used to construct an UpdateValue command.
static class	UpdateValue.Response
static class	UpdateValue.Update<T> An update on a Riak object

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
protected RiakFuture<UpdateValue.Response,Location>	executeAsync(RiakCluster cluster)
int	hashCode()
String	toString()

Methods inherited from class com.basho.riak.client.api.RiakCommand

execute, execute

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

executeAsync

protected RiakFuture<UpdateValue.Response,Location> executeAsync(RiakCluster cluster)

Specified by:

executeAsync in class RiakCommand<UpdateValue.Response,Location>

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object