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.client;
019
020import java.util.Collections;
021import java.util.HashMap;
022import java.util.Map;
023import java.util.TreeMap;
024import java.util.stream.Collectors;
025import org.apache.hadoop.hbase.HConstants;
026import org.apache.hadoop.hbase.util.Bytes;
027import org.apache.hadoop.hbase.util.ClassSize;
028import org.apache.yetus.audience.InterfaceAudience;
029
030@InterfaceAudience.Public
031public abstract class OperationWithAttributes extends Operation implements Attributes {
032  // An opaque blob of attributes
033  private Map<String, byte[]> attributes;
034
035  // used for uniquely identifying an operation
036  public static final String ID_ATRIBUTE = "_operation.attributes.id";
037  private int priority = HConstants.PRIORITY_UNSET;
038
039  /**
040   * empty construction. We need this empty construction to keep binary compatibility.
041   */
042  protected OperationWithAttributes() {
043  }
044
045  protected OperationWithAttributes(OperationWithAttributes clone) {
046    this.attributes = clone.getAttributesMap() == null
047      ? null
048      : clone.getAttributesMap().entrySet().stream()
049        .collect(Collectors.toMap(e -> e.getKey(), e -> e.getValue(), (k, v) -> {
050          throw new RuntimeException("collisions!!!");
051        }, () -> new TreeMap<>()));
052    this.priority = clone.getPriority();
053  }
054
055  @Override
056  public OperationWithAttributes setAttribute(String name, byte[] value) {
057    if (attributes == null && value == null) {
058      return this;
059    }
060
061    if (attributes == null) {
062      attributes = new HashMap<>();
063    }
064
065    if (value == null) {
066      attributes.remove(name);
067      if (attributes.isEmpty()) {
068        this.attributes = null;
069      }
070    } else {
071      attributes.put(name, value);
072    }
073    return this;
074  }
075
076  @Override
077  public byte[] getAttribute(String name) {
078    if (attributes == null) {
079      return null;
080    }
081
082    return attributes.get(name);
083  }
084
085  @Override
086  public Map<String, byte[]> getAttributesMap() {
087    if (attributes == null) {
088      return Collections.emptyMap();
089    }
090    return Collections.unmodifiableMap(attributes);
091  }
092
093  protected long getAttributeSize() {
094    long size = 0;
095    if (attributes != null) {
096      size += ClassSize.align(this.attributes.size() * ClassSize.MAP_ENTRY);
097      for (Map.Entry<String, byte[]> entry : this.attributes.entrySet()) {
098        size += ClassSize.align(ClassSize.STRING + entry.getKey().length());
099        size += ClassSize.align(ClassSize.ARRAY + entry.getValue().length);
100      }
101    }
102    return size;
103  }
104
105  /**
106   * This method allows you to set an identifier on an operation. The original motivation for this
107   * was to allow the identifier to be used in slow query logging, but this could obviously be
108   * useful in other places. One use of this could be to put a class.method identifier in here to
109   * see where the slow query is coming from. id to set for the scan
110   */
111  public OperationWithAttributes setId(String id) {
112    setAttribute(ID_ATRIBUTE, Bytes.toBytes(id));
113    return this;
114  }
115
116  /**
117   * This method allows you to retrieve the identifier for the operation if one was set.
118   * @return the id or null if not set
119   */
120  public String getId() {
121    byte[] attr = getAttribute(ID_ATRIBUTE);
122    return attr == null ? null : Bytes.toString(attr);
123  }
124
125  public OperationWithAttributes setPriority(int priority) {
126    this.priority = priority;
127    return this;
128  }
129
130  public int getPriority() {
131    return priority;
132  }
133
134}