/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.client.coprocessor;
import java.io.IOException;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
/**
* A collection of interfaces and utilities used for interacting with custom RPC
* interfaces exposed by Coprocessors.
*/
@InterfaceAudience.Public
public abstract class Batch {
/**
* Defines a unit of work to be executed.
*
* <p>
* When used with
* {@link org.apache.hadoop.hbase.client.Table#coprocessorService(Class, byte[], byte[],
* org.apache.hadoop.hbase.client.coprocessor.Batch.Call)}
* the implementations {@link Batch.Call#call(Object)} method will be invoked
* with a proxy to each region's coprocessor {@link com.google.protobuf.Service} implementation.
* </p>
* @see org.apache.hadoop.hbase.client.coprocessor
* @see org.apache.hadoop.hbase.client.Table#coprocessorService(byte[])
* @see org.apache.hadoop.hbase.client.Table#coprocessorService(Class, byte[], byte[],
* org.apache.hadoop.hbase.client.coprocessor.Batch.Call)
* @param <T> the instance type to be passed to
* {@link Batch.Call#call(Object)}
* @param <R> the return type from {@link Batch.Call#call(Object)}
*/
@InterfaceAudience.Public
public interface Call<T,R> {
R call(T instance) throws IOException;
}
/**
* Defines a generic callback to be triggered for each {@link Batch.Call#call(Object)}
* result.
*
* <p>
* When used with
* {@link org.apache.hadoop.hbase.client.Table#coprocessorService(Class, byte[], byte[],
* org.apache.hadoop.hbase.client.coprocessor.Batch.Call)}
* the implementation's {@link Batch.Callback#update(byte[], byte[], Object)}
* method will be called with the {@link Batch.Call#call(Object)} return value
* from each region in the selected range.
* </p>
* @param <R> the return type from the associated {@link Batch.Call#call(Object)}
* @see org.apache.hadoop.hbase.client.Table#coprocessorService(Class, byte[], byte[],
* org.apache.hadoop.hbase.client.coprocessor.Batch.Call)
*/
@InterfaceAudience.Public
public interface Callback<R> {
void update(byte[] region, byte[] row, R result);
}
}