org.teiid.language.AggregateFunction Maven / Gradle / Ivy
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* Copyright Red Hat, Inc. and/or its affiliates
* and other contributors as indicated by the @author tags and
* the COPYRIGHT.txt file distributed with this work.
*
* Licensed 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.teiid.language;
import java.util.List;
import org.teiid.language.visitor.LanguageObjectVisitor;
/**
* Represents an aggregate function.
*/
public class AggregateFunction extends Function {
public static final String COUNT = "COUNT"; //$NON-NLS-1$
public static final String AVG = "AVG"; //$NON-NLS-1$
public static final String SUM = "SUM"; //$NON-NLS-1$
public static final String MIN = "MIN"; //$NON-NLS-1$
public static final String MAX = "MAX"; //$NON-NLS-1$
public static final String STDDEV_POP = "STDDEV_POP"; //$NON-NLS-1$
public static final String STDDEV_SAMP = "STDDEV_SAMP"; //$NON-NLS-1$
public static final String VAR_SAMP = "VAR_SAMP"; //$NON-NLS-1$
public static final String VAR_POP = "VAR_POP"; //$NON-NLS-1$
private String aggName;
private boolean isDistinct;
private Expression condition;
private OrderBy orderBy;
public AggregateFunction(String aggName, boolean isDistinct, List params, Class type) {
super(aggName, params, type);
this.aggName = aggName;
this.isDistinct = isDistinct;
}
/**
* Get the name of the aggregate function. This will be one of the constants defined
* in this class.
*/
public String getName() {
return this.aggName;
}
/**
* Determine whether this function was executed with DISTINCT. Executing
* with DISTINCT will remove all duplicate values in a group when evaluating
* the aggregate function.
* @return True if DISTINCT mode is used
*/
public boolean isDistinct() {
return this.isDistinct;
}
/**
* Get the expression within the aggregate function. The expression will be
* null for the special case COUNT(*). This is the only case where the
* expression will be null
* Only valid for 0/1 ary aggregates
* @return The expression or null for COUNT(*)
* @deprecated
*/
public Expression getExpression() {
if (this.getParameters().isEmpty()) {
return null;
}
return this.getParameters().get(0);
}
public void acceptVisitor(LanguageObjectVisitor visitor) {
visitor.visit(this);
}
/**
* Set the name of the aggregate function. This will be one of the constants defined
* in this class.
* @param name New aggregate function name
*/
public void setName(String name) {
this.aggName = name;
}
/**
* Set whether this function was executed with DISTINCT. Executing
* with DISTINCT will remove all duplicate values in a group when evaluating
* the aggregate function.
* @param isDistinct True if DISTINCT mode should be used
*/
public void setDistinct(boolean isDistinct) {
this.isDistinct = isDistinct;
}
/**
*
* @return the filter clause condition
*/
public Expression getCondition() {
return condition;
}
public void setCondition(Expression condition) {
this.condition = condition;
}
public OrderBy getOrderBy() {
return orderBy;
}
public void setOrderBy(OrderBy orderBy) {
this.orderBy = orderBy;
}
}