library/src/main/java/com/datatorrent/lib/chart/ChartOperator.java

/*
 * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved.
 *
 * 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 com.datatorrent.lib.chart;

import com.datatorrent.api.BaseOperator;
import com.datatorrent.api.annotation.OperatorAnnotation;

/**
 * This is the base implementation of a charting operator. 
 * Subclasses should implement the method that returns the chart type.
 *
 * <p></p>
 * @displayName Abstract Chart
 * @category Charting
 * @tags output operator
 *
 * @since 0.3.2
 */
@OperatorAnnotation(partitionable=false)
public abstract class ChartOperator extends BaseOperator
{
  /**
   * The different types of chart
   */
  public enum Type
  {
    /**
     * Line - One point for each data item. Both X-axis and Y-axis are numbers. X-axis is usually a time-series
     */
    LINE,
    /**
     * Candle - Four points for each data item (open, close, high, low). Both X-axis and Y-axis are numbers. X-axis is usually a time series
     */
    CANDLE,
    /**
     * Enumerated - X-axis is an enumeration set. Y-axis is a number
     */
    ENUM,
    /**
     * Histogram - Like ENUM, except X-axis is a set of ranges.
     */
    HISTOGRAM,
  }

  /**
   * Gets the chart type
   *
   * @return The chart type
   */
  public abstract Type getChartType();

}