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.Map; 021import org.apache.hadoop.hbase.exceptions.DeserializationException; 022import org.apache.hadoop.hbase.filter.Filter; 023import org.apache.hadoop.hbase.io.TimeRange; 024import org.apache.hadoop.hbase.security.access.AccessControlConstants; 025import org.apache.hadoop.hbase.security.access.AccessControlUtil; 026import org.apache.hadoop.hbase.security.access.Permission; 027import org.apache.hadoop.hbase.security.visibility.Authorizations; 028import org.apache.hadoop.hbase.security.visibility.VisibilityConstants; 029import org.apache.hadoop.hbase.util.Bytes; 030import org.apache.yetus.audience.InterfaceAudience; 031 032import org.apache.hbase.thirdparty.com.google.common.collect.ArrayListMultimap; 033import org.apache.hbase.thirdparty.com.google.common.collect.ListMultimap; 034import org.apache.hbase.thirdparty.com.google.common.collect.Maps; 035 036import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil; 037 038/** 039 * Base class for HBase read operations; e.g. Scan and Get. 040 */ 041@InterfaceAudience.Public 042public abstract class Query extends OperationWithAttributes { 043 private static final String ISOLATION_LEVEL = "_isolationlevel_"; 044 protected Filter filter = null; 045 protected int targetReplicaId = -1; 046 protected Consistency consistency = Consistency.STRONG; 047 protected Map<byte[], TimeRange> colFamTimeRangeMap = Maps.newTreeMap(Bytes.BYTES_COMPARATOR); 048 protected Boolean loadColumnFamiliesOnDemand = null; 049 050 public Filter getFilter() { 051 return filter; 052 } 053 054 /** 055 * Apply the specified server-side filter when performing the Query. Only 056 * {@link Filter#filterCell(org.apache.hadoop.hbase.Cell)} is called AFTER all tests for ttl, 057 * column match, deletes and column family's max versions have been run. 058 * @param filter filter to run on the server 059 * @return this for invocation chaining 060 */ 061 public Query setFilter(Filter filter) { 062 this.filter = filter; 063 return this; 064 } 065 066 /** 067 * Sets the authorizations to be used by this Query 068 */ 069 public Query setAuthorizations(Authorizations authorizations) { 070 this.setAttribute(VisibilityConstants.VISIBILITY_LABELS_ATTR_KEY, 071 ProtobufUtil.toAuthorizations(authorizations).toByteArray()); 072 return this; 073 } 074 075 /** Returns The authorizations this Query is associated with. n */ 076 public Authorizations getAuthorizations() throws DeserializationException { 077 byte[] authorizationsBytes = this.getAttribute(VisibilityConstants.VISIBILITY_LABELS_ATTR_KEY); 078 if (authorizationsBytes == null) return null; 079 return ProtobufUtil.toAuthorizations(authorizationsBytes); 080 } 081 082 /** Returns The serialized ACL for this operation, or null if none */ 083 public byte[] getACL() { 084 return getAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL); 085 } 086 087 /** 088 * @param user User short name 089 * @param perms Permissions for the user 090 */ 091 public Query setACL(String user, Permission perms) { 092 setAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL, 093 AccessControlUtil.toUsersAndPermissions(user, perms).toByteArray()); 094 return this; 095 } 096 097 /** 098 * @param perms A map of permissions for a user or users 099 */ 100 public Query setACL(Map<String, Permission> perms) { 101 ListMultimap<String, Permission> permMap = ArrayListMultimap.create(); 102 for (Map.Entry<String, Permission> entry : perms.entrySet()) { 103 permMap.put(entry.getKey(), entry.getValue()); 104 } 105 setAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL, 106 AccessControlUtil.toUsersAndPermissions(permMap).toByteArray()); 107 return this; 108 } 109 110 /** 111 * Returns the consistency level for this operation 112 * @return the consistency level 113 */ 114 public Consistency getConsistency() { 115 return consistency; 116 } 117 118 /** 119 * Sets the consistency level for this operation 120 * @param consistency the consistency level 121 */ 122 public Query setConsistency(Consistency consistency) { 123 this.consistency = consistency; 124 return this; 125 } 126 127 /** 128 * Specify region replica id where Query will fetch data from. Use this together with 129 * {@link #setConsistency(Consistency)} passing {@link Consistency#TIMELINE} to read data from a 130 * specific replicaId. <br> 131 * <b> Expert: </b>This is an advanced API exposed. Only use it if you know what you are doing 132 */ 133 public Query setReplicaId(int Id) { 134 this.targetReplicaId = Id; 135 return this; 136 } 137 138 /** 139 * Returns region replica id where Query will fetch data from. 140 * @return region replica id or -1 if not set. 141 */ 142 public int getReplicaId() { 143 return this.targetReplicaId; 144 } 145 146 /** 147 * Set the isolation level for this query. If the isolation level is set to READ_UNCOMMITTED, then 148 * this query will return data from committed and uncommitted transactions. If the isolation level 149 * is set to READ_COMMITTED, then this query will return data from committed transactions only. If 150 * a isolation level is not explicitly set on a Query, then it is assumed to be READ_COMMITTED. 151 * @param level IsolationLevel for this query 152 */ 153 public Query setIsolationLevel(IsolationLevel level) { 154 setAttribute(ISOLATION_LEVEL, level.toBytes()); 155 return this; 156 } 157 158 /** 159 * @return The isolation level of this query. If no isolation level was set for this query object, 160 * then it returns READ_COMMITTED. 161 * @return The IsolationLevel for this query 162 */ 163 public IsolationLevel getIsolationLevel() { 164 byte[] attr = getAttribute(ISOLATION_LEVEL); 165 return attr == null ? IsolationLevel.READ_COMMITTED : IsolationLevel.fromBytes(attr); 166 } 167 168 /** 169 * Set the value indicating whether loading CFs on demand should be allowed (cluster default is 170 * false). On-demand CF loading doesn't load column families until necessary, e.g. if you filter 171 * on one column, the other column family data will be loaded only for the rows that are included 172 * in result, not all rows like in normal case. With column-specific filters, like 173 * SingleColumnValueFilter w/filterIfMissing == true, this can deliver huge perf gains when 174 * there's a cf with lots of data; however, it can also lead to some inconsistent results, as 175 * follows: - if someone does a concurrent update to both column families in question you may get 176 * a row that never existed, e.g. for { rowKey = 5, { cat_videos => 1 }, { video => "my cat" 177 * } } someone puts rowKey 5 with { cat_videos => 0 }, { video => "my dog" }, concurrent 178 * scan filtering on "cat_videos == 1" can get { rowKey = 5, { cat_videos => 1 }, { video => 179 * "my dog" } }. - if there's a concurrent split and you have more than 2 column families, some 180 * rows may be missing some column families. 181 */ 182 public Query setLoadColumnFamiliesOnDemand(boolean value) { 183 this.loadColumnFamiliesOnDemand = value; 184 return this; 185 } 186 187 /** 188 * Get the raw loadColumnFamiliesOnDemand setting; if it's not set, can be null. 189 */ 190 public Boolean getLoadColumnFamiliesOnDemandValue() { 191 return this.loadColumnFamiliesOnDemand; 192 } 193 194 /** 195 * Get the logical value indicating whether on-demand CF loading should be allowed. 196 */ 197 public boolean doLoadColumnFamiliesOnDemand() { 198 return (this.loadColumnFamiliesOnDemand != null) && this.loadColumnFamiliesOnDemand; 199 } 200 201 /** 202 * Get versions of columns only within the specified timestamp range, [minStamp, maxStamp) on a 203 * per CF bases. Note, default maximum versions to return is 1. If your time range spans more than 204 * one version and you want all versions returned, up the number of versions beyond the default. 205 * Column Family time ranges take precedence over the global time range. 206 * @param cf the column family for which you want to restrict 207 * @param minStamp minimum timestamp value, inclusive 208 * @param maxStamp maximum timestamp value, exclusive 209 */ 210 211 public Query setColumnFamilyTimeRange(byte[] cf, long minStamp, long maxStamp) { 212 colFamTimeRangeMap.put(cf, new TimeRange(minStamp, maxStamp)); 213 return this; 214 } 215 216 /** Returns A map of column families to time ranges */ 217 public Map<byte[], TimeRange> getColumnFamilyTimeRange() { 218 return this.colFamTimeRangeMap; 219 } 220}