org.apache.hadoop.hive.ql.parse.ColumnAccessInfo Maven / Gradle / Ivy
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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.hive.ql.parse;
import org.apache.hadoop.hive.ql.metadata.VirtualColumn;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
public class ColumnAccessInfo {
/**
* Map of table name to names of accessed columns
*/
private final Map> tableToColumnAccessMap;
public ColumnAccessInfo() {
// Must be deterministic order map for consistent q-test output across Java versions
tableToColumnAccessMap = new LinkedHashMap>();
}
public void add(String table, String col) {
Set tableColumns = tableToColumnAccessMap.get(table);
if (tableColumns == null) {
// Must be deterministic order set for consistent q-test output across Java versions
tableColumns = new LinkedHashSet();
tableToColumnAccessMap.put(table, tableColumns);
}
tableColumns.add(col);
}
public Map> getTableToColumnAccessMap() {
// Must be deterministic order map for consistent q-test output across Java versions
Map> mapping = new LinkedHashMap>();
for (Map.Entry> entry : tableToColumnAccessMap.entrySet()) {
List sortedCols = new ArrayList(entry.getValue());
Collections.sort(sortedCols);
mapping.put(entry.getKey(), sortedCols);
}
return mapping;
}
/**
* Strip a virtual column out of the set of columns. This is useful in cases where we do not
* want to be checking against the user reading virtual columns, namely update and delete.
* @param vc
*/
public void stripVirtualColumn(VirtualColumn vc) {
for (Map.Entry> e : tableToColumnAccessMap.entrySet()) {
for (String columnName : e.getValue()) {
if (vc.getName().equalsIgnoreCase(columnName)) {
e.getValue().remove(columnName);
break;
}
}
}
}
}