hbase-client/src/main/java/org/apache/hadoop/hbase/client/OperationWithAttributes.java

   1 /*
   2  *
   3  * Licensed to the Apache Software Foundation (ASF) under one
   4  * or more contributor license agreements.  See the NOTICE file
   5  * distributed with this work for additional information
   6  * regarding copyright ownership.  The ASF licenses this file
   7  * to you under the Apache License, Version 2.0 (the
   8  * "License"); you may not use this file except in compliance
   9  * with the License.  You may obtain a copy of the License at
  10  *
  11  *     http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  */
  19
  20 package org.apache.hadoop.hbase.client;
  21
  22 import java.util.Collections;
  23 import java.util.HashMap;
  24 import java.util.Map;
  25 import java.util.TreeMap;
  26 import java.util.stream.Collectors;
  27 import org.apache.hadoop.hbase.HConstants;
  28 import org.apache.hadoop.hbase.util.Bytes;
  29 import org.apache.hadoop.hbase.util.ClassSize;
  30 import org.apache.yetus.audience.InterfaceAudience;
  31
  32 @InterfaceAudience.Public
  33 public abstract class OperationWithAttributes extends Operation implements Attributes {
  34   // An opaque blob of attributes
  35   private Map<String, byte[]> attributes;
  36
  37   // used for uniquely identifying an operation
  38   public static final String ID_ATRIBUTE = "_operation.attributes.id";
  39   private int priority = HConstants.PRIORITY_UNSET;
  40
  41   /**
  42    * empty construction.
  43    * We need this empty construction to keep binary compatibility.
  44    */
  45   protected OperationWithAttributes() {
  46   }
  47
  48   protected OperationWithAttributes(OperationWithAttributes clone) {
  49     this.attributes = clone.getAttributesMap() == null ? null :
  50       clone.getAttributesMap().entrySet().stream()
  51         .collect(Collectors.toMap(e -> e.getKey(), e -> e.getValue(), (k, v) -> {
  52           throw new RuntimeException("collisions!!!");
  53         }, () -> new TreeMap<>()));
  54     this.priority = clone.getPriority();
  55   }
  56
  57   @Override
  58   public OperationWithAttributes setAttribute(String name, byte[] value) {
  59     if (attributes == null && value == null) {
  60       return this;
  61     }
  62
  63     if (attributes == null) {
  64       attributes = new HashMap<>();
  65     }
  66
  67     if (value == null) {
  68       attributes.remove(name);
  69       if (attributes.isEmpty()) {
  70         this.attributes = null;
  71       }
  72     } else {
  73       attributes.put(name, value);
  74     }
  75     return this;
  76   }
  77
  78   @Override
  79   public byte[] getAttribute(String name) {
  80     if (attributes == null) {
  81       return null;
  82     }
  83
  84     return attributes.get(name);
  85   }
  86
  87   @Override
  88   public Map<String, byte[]> getAttributesMap() {
  89     if (attributes == null) {
  90       return Collections.emptyMap();
  91     }
  92     return Collections.unmodifiableMap(attributes);
  93   }
  94
  95   protected long getAttributeSize() {
  96     long size = 0;
  97     if (attributes != null) {
  98       size += ClassSize.align(this.attributes.size() * ClassSize.MAP_ENTRY);
  99       for(Map.Entry<String, byte[]> entry : this.attributes.entrySet()) {
 100         size += ClassSize.align(ClassSize.STRING + entry.getKey().length());
 101         size += ClassSize.align(ClassSize.ARRAY + entry.getValue().length);
 102       }
 103     }
 104     return size;
 105   }
 106
 107   /**
 108    * This method allows you to set an identifier on an operation. The original
 109    * motivation for this was to allow the identifier to be used in slow query
 110    * logging, but this could obviously be useful in other places. One use of
 111    * this could be to put a class.method identifier in here to see where the
 112    * slow query is coming from.
 113    * @param id
 114    *          id to set for the scan
 115    */
 116   public OperationWithAttributes setId(String id) {
 117     setAttribute(ID_ATRIBUTE, Bytes.toBytes(id));
 118     return this;
 119   }
 120
 121   /**
 122    * This method allows you to retrieve the identifier for the operation if one
 123    * was set.
 124    * @return the id or null if not set
 125    */
 126   public String getId() {
 127     byte[] attr = getAttribute(ID_ATRIBUTE);
 128     return attr == null? null: Bytes.toString(attr);
 129   }
 130
 131   public OperationWithAttributes setPriority(int priority) {
 132     this.priority = priority;
 133     return this;
 134   }
 135
 136   public int getPriority() {
 137     return priority;
 138   }
 139
 140 }