/*
* ====================================================================
* 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.poi.ss.usermodel.charts;
import org.apache.poi.util.Beta;
/**
* Represents data model of the charts.
*
* @param <T> type of points the data source contents
* @author Roman Kashitsyn
*/
@Beta
public interface ChartDataSource<T> {
/**
* Return number of points contained by data source.
*
* @return number of points contained by data source
*/
int getPointCount();
/**
* Returns point value at specified index.
*
* @param index index to value from
* @return point value at specified index.
* @throws {@code IndexOutOfBoundsException} if index
* parameter not in range {@code 0 <= index <= pointCount}
*/
T getPointAt(int index);
/**
* Returns {@code true} if charts data source is valid cell range.
*
* @return {@code true} if charts data source is valid cell range
*/
boolean isReference();
/**
* Returns {@code true} if data source points should be treated as numbers.
*
* @return {@code true} if data source points should be treated as numbers
*/
boolean isNumeric();
/**
* Returns formula representation of the data source. It is only applicable
* for data source that is valid cell range.
*
* @return formula representation of the data source
* @throws {@code UnsupportedOperationException} if the data source is not a
* reference.
*/
String getFormulaString();
}