org.apache.calcite.model.JsonFunction 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.calcite.model;
import java.util.List;
/**
* Function schema element.
*
* @see JsonRoot Description of schema elements
*/
public class JsonFunction {
/** Name of this function.
*
* Required.
*/
public String name;
/** Name of the class that implements this function.
*
*
Required.
*/
public String className;
/** Name of the method that implements this function.
*
*
Optional.
*
*
If specified, the method must exist (case-sensitive) and Calcite
* will create a scalar function. The method may be static or non-static, but
* if non-static, the class must have a public constructor with no parameters.
*
*
If "*", Calcite creates a function for every method
* in this class.
*
*
If not specified, Calcite looks for a method called "eval", and
* if found, creates a a table macro or scalar function.
* It also looks for methods "init", "add", "merge", "result", and
* if found, creates an aggregate function.
*/
public String methodName;
/** Path for resolving this function.
*
*
Optional.
*/
public List path;
public void accept(ModelHandler handler) {
handler.visit(this);
}
}
// End JsonFunction.java