/*
* 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.ambari.view.hive20.internal.query.generators;
import com.google.common.base.Optional;
import org.apache.ambari.view.hive20.exceptions.ServiceException;
import org.apache.parquet.Strings;
public class RenameTableQueryGenerator implements QueryGenerator {
private String oldDatabaseName;
private final String oldTableName;
private final String newDatabaseName;
private final String newTableName;
public RenameTableQueryGenerator(String oldDatabaseName, String oldTableName, String newDatabaseName, String newTableName) {
this.oldDatabaseName = oldDatabaseName;
this.oldTableName = oldTableName;
this.newDatabaseName = newDatabaseName;
this.newTableName = newTableName;
}
public String getOldDatabaseName() {
return oldDatabaseName;
}
public String getOldTableName() {
return oldTableName;
}
public String getNewDatabaseName() {
return newDatabaseName;
}
public String getNewTableName() {
return newTableName;
}
/**
* ALTER TABLE table_name RENAME TO new_table_name;
* @return Optional rename query if table has changed.
* @throws ServiceException
*/
@Override
public Optional<String> getQuery() throws ServiceException {
StringBuilder queryBuilder = new StringBuilder("ALTER TABLE `");
if(!Strings.isNullOrEmpty(this.getOldDatabaseName())){
queryBuilder.append(this.getOldDatabaseName().trim()).append("`.`");
}
if(!Strings.isNullOrEmpty(this.getOldTableName())){
queryBuilder.append(this.getOldTableName().trim());
}else{
throw new ServiceException("current table name cannot be null or empty.");
}
queryBuilder.append("` RENAME TO `");
if(!Strings.isNullOrEmpty(this.getNewDatabaseName())){
queryBuilder.append(this.getNewDatabaseName().trim()).append("`.`");
}
if(!Strings.isNullOrEmpty(this.getNewTableName())){
queryBuilder.append(this.getNewTableName().trim());
}else{
throw new ServiceException("new table name cannot be null or empty.");
}
queryBuilder.append("`");
return Optional.of(queryBuilder.toString());
}
}