001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.coprocessor; 019 020import java.lang.annotation.ElementType; 021import java.lang.annotation.Inherited; 022import java.lang.annotation.Retention; 023import java.lang.annotation.RetentionPolicy; 024import java.lang.annotation.Target; 025import org.apache.yetus.audience.InterfaceAudience; 026 027/** 028 * Marker annotation that denotes Coprocessors that are core to HBase. A Core Coprocessor is a CP 029 * that realizes a core HBase feature. Features are sometimes implemented first as a Coprocessor to 030 * prove viability. The idea is that once proven, they then migrate to core. Meantime, HBase Core 031 * Coprocessors get this annotation. No other Coprocessors can carry this annotation. 032 */ 033// Core Coprocessors are generally naughty making use of HBase internals doing accesses no 034// Coprocessor should be up to so we mark these special Coprocessors with this annotation and on 035// Coprocessor load, we'll give these Coprocessors a 'richer' Environment with access to internals 036// not allowed other Coprocessors. see the *CoprocessorHost where they do the Coprocessor loadings. 037@Target(ElementType.TYPE) 038@Inherited 039@InterfaceAudience.Private 040@Retention(RetentionPolicy.RUNTIME) 041// This Annotation is not @Documented because I don't want users figuring out its mechanics. 042public @interface CoreCoprocessor { 043}