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 * 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;

import java.util.Map;
import org.apache.hadoop.hbase.exceptions.DeserializationException;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.io.TimeRange;
import org.apache.hadoop.hbase.security.access.AccessControlConstants;
import org.apache.hadoop.hbase.security.access.AccessControlUtil;
import org.apache.hadoop.hbase.security.access.Permission;
import org.apache.hadoop.hbase.security.visibility.Authorizations;
import org.apache.hadoop.hbase.security.visibility.VisibilityConstants;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.yetus.audience.InterfaceAudience;

import org.apache.hbase.thirdparty.com.google.common.collect.ArrayListMultimap;
import org.apache.hbase.thirdparty.com.google.common.collect.ListMultimap;
import org.apache.hbase.thirdparty.com.google.common.collect.Maps;

import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;

/**
 * Base class for HBase read operations; e.g. Scan and Get.
 */
@InterfaceAudience.Public
public abstract class Query extends OperationWithAttributes {
  private static final String ISOLATION_LEVEL = "_isolationlevel_";
  protected Filter filter = null;
  protected int targetReplicaId = -1;
  protected Consistency consistency = Consistency.STRONG;
  protected Map colFamTimeRangeMap = Maps.newTreeMap(Bytes.BYTES_COMPARATOR);
  protected Boolean loadColumnFamiliesOnDemand = null;

  public Filter getFilter() {
    return filter;
  }

  /**
   * Apply the specified server-side filter when performing the Query. Only
   * {@link Filter#filterCell(org.apache.hadoop.hbase.Cell)} is called AFTER all tests for ttl,
   * column match, deletes and column family's max versions have been run.
   * @param filter filter to run on the server
   * @return this for invocation chaining
   */
  public Query setFilter(Filter filter) {
    this.filter = filter;
    return this;
  }

  /**
   * Sets the authorizations to be used by this Query
   */
  public Query setAuthorizations(Authorizations authorizations) {
    this.setAttribute(VisibilityConstants.VISIBILITY_LABELS_ATTR_KEY,
      ProtobufUtil.toAuthorizations(authorizations).toByteArray());
    return this;
  }

  /** Returns The authorizations this Query is associated with. n */
  public Authorizations getAuthorizations() throws DeserializationException {
    byte[] authorizationsBytes = this.getAttribute(VisibilityConstants.VISIBILITY_LABELS_ATTR_KEY);
    if (authorizationsBytes == null) return null;
    return ProtobufUtil.toAuthorizations(authorizationsBytes);
  }

  /** Returns The serialized ACL for this operation, or null if none */
  public byte[] getACL() {
    return getAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL);
  }

  /**
   * Set the ACL for the operation.
   * @param user  User short name
   * @param perms Permissions for the user
   */
  public Query setACL(String user, Permission perms) {
    setAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL,
      AccessControlUtil.toUsersAndPermissions(user, perms).toByteArray());
    return this;
  }

  /**
   * Set the ACL for the operation.
   * @param perms A map of permissions for a user or users
   */
  public Query setACL(Map perms) {
    ListMultimap permMap = ArrayListMultimap.create();
    for (Map.Entry entry : perms.entrySet()) {
      permMap.put(entry.getKey(), entry.getValue());
    }
    setAttribute(AccessControlConstants.OP_ATTRIBUTE_ACL,
      AccessControlUtil.toUsersAndPermissions(permMap).toByteArray());
    return this;
  }

  /**
   * Returns the consistency level for this operation
   * @return the consistency level
   */
  public Consistency getConsistency() {
    return consistency;
  }

  /**
   * Sets the consistency level for this operation
   * @param consistency the consistency level
   */
  public Query setConsistency(Consistency consistency) {
    this.consistency = consistency;
    return this;
  }

  /**
   * Specify region replica id where Query will fetch data from. Use this together with
   * {@link #setConsistency(Consistency)} passing {@link Consistency#TIMELINE} to read data from a
   * specific replicaId. 
* Expert: This is an advanced API exposed. Only use it if you know what you are doing */ public Query setReplicaId(int Id) { this.targetReplicaId = Id; return this; } /** * Returns region replica id where Query will fetch data from. * @return region replica id or -1 if not set. */ public int getReplicaId() { return this.targetReplicaId; } /** * Set the isolation level for this query. If the isolation level is set to READ_UNCOMMITTED, then * this query will return data from committed and uncommitted transactions. If the isolation level * is set to READ_COMMITTED, then this query will return data from committed transactions only. If * a isolation level is not explicitly set on a Query, then it is assumed to be READ_COMMITTED. * @param level IsolationLevel for this query */ public Query setIsolationLevel(IsolationLevel level) { setAttribute(ISOLATION_LEVEL, level.toBytes()); return this; } /** * Returns The isolation level of this query. If no isolation level was set for this query object, * then it returns READ_COMMITTED. */ public IsolationLevel getIsolationLevel() { byte[] attr = getAttribute(ISOLATION_LEVEL); return attr == null ? IsolationLevel.READ_COMMITTED : IsolationLevel.fromBytes(attr); } /** * Set the value indicating whether loading CFs on demand should be allowed (cluster default is * false). On-demand CF loading doesn't load column families until necessary, e.g. if you filter * on one column, the other column family data will be loaded only for the rows that are included * in result, not all rows like in normal case. With column-specific filters, like * SingleColumnValueFilter w/filterIfMissing == true, this can deliver huge perf gains when * there's a cf with lots of data; however, it can also lead to some inconsistent results, as * follows: - if someone does a concurrent update to both column families in question you may get * a row that never existed, e.g. for { rowKey = 5, { cat_videos => 1 }, { video => "my cat" * } } someone puts rowKey 5 with { cat_videos => 0 }, { video => "my dog" }, concurrent * scan filtering on "cat_videos == 1" can get { rowKey = 5, { cat_videos => 1 }, { video => * "my dog" } }. - if there's a concurrent split and you have more than 2 column families, some * rows may be missing some column families. */ public Query setLoadColumnFamiliesOnDemand(boolean value) { this.loadColumnFamiliesOnDemand = value; return this; } /** * Get the raw loadColumnFamiliesOnDemand setting; if it's not set, can be null. */ public Boolean getLoadColumnFamiliesOnDemandValue() { return this.loadColumnFamiliesOnDemand; } /** * Get the logical value indicating whether on-demand CF loading should be allowed. */ public boolean doLoadColumnFamiliesOnDemand() { return (this.loadColumnFamiliesOnDemand != null) && this.loadColumnFamiliesOnDemand; } /** * Get versions of columns only within the specified timestamp range, [minStamp, maxStamp) on a * per CF bases. Note, default maximum versions to return is 1. If your time range spans more than * one version and you want all versions returned, up the number of versions beyond the default. * Column Family time ranges take precedence over the global time range. * @param cf the column family for which you want to restrict * @param minStamp minimum timestamp value, inclusive * @param maxStamp maximum timestamp value, exclusive */ public Query setColumnFamilyTimeRange(byte[] cf, long minStamp, long maxStamp) { colFamTimeRangeMap.put(cf, new TimeRange(minStamp, maxStamp)); return this; } /** Returns A map of column families to time ranges */ public Map getColumnFamilyTimeRange() { return this.colFamTimeRangeMap; } }




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