com.datatorrent.lib.streamquery.condition.JoinColumnEqualCondition Maven / Gradle / Ivy
/**
* 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 com.datatorrent.lib.streamquery.condition;
import java.util.Map;
import javax.validation.constraints.NotNull;
/**
* An implementation of equal join condition class.
*
* This compares values of given keys in both row data.
*
* Properties :
* Keys for which value must be compared.
*
* @displayName Join Column Equal Condition
* @category Stream Manipulators
* @tags sql condition, equal join
* @since 0.3.3
*/
public class JoinColumnEqualCondition extends Condition
{
/**
* column names to be compared.
*/
@NotNull
private String column1;
@NotNull
private String column2;
public JoinColumnEqualCondition(@NotNull String column1, @NotNull String column2)
{
this.column1 = column1;
this.column2 = column2;
}
/**
* Must never be called.
*/
@Override
public boolean isValidRow(Map row)
{
assert (false);
return false;
}
/**
*
*/
@Override
public boolean isValidJoin(Map row1, Map row2)
{
if (!row1.containsKey(column1) || !row2.containsKey(column2)) {
return false;
}
Object value1 = row1.get(column1);
Object value2 = row2.get(column2);
return value1.equals(value2);
}
}