DataTableColumn.java

/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 by RapidMiner and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapidminer.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.new_plotter.configuration;

import com.rapidminer.datatable.DataTable;
import com.rapidminer.tools.Ontology;

/**
 * This class describes a column of a {@link DataTable} characterized by a name, a column index
 * and a {@link ValueType}.
 * 
 * @author Nils Woehler, Marius Helf
 *
 */
public class DataTableColumn implements Cloneable {
	
	public enum ValueType{
		INVALID,
		UNKNOWN,
		NOMINAL,
		NUMERICAL,
		DATE_TIME;
		
		public static int convertToRapidMinerOntology(ValueType valueType) {
			switch(valueType) {
			case DATE_TIME:
				return Ontology.DATE_TIME;
			case INVALID:
				return Ontology.ATTRIBUTE_VALUE;
			case NUMERICAL:
				return Ontology.NUMERICAL;
			case UNKNOWN:
			case NOMINAL:
			default:
				return Ontology.NOMINAL;
			}
		}
		
		public static ValueType convertFromRapidMinerOntology(int rmValueType) {
			if (Ontology.ATTRIBUTE_VALUE_TYPE.isA(rmValueType, Ontology.NUMERICAL)) {
				return NUMERICAL;
			} else if (Ontology.ATTRIBUTE_VALUE_TYPE.isA(rmValueType, Ontology.NOMINAL)) {
				return NOMINAL;
			} else if (Ontology.ATTRIBUTE_VALUE_TYPE.isA(rmValueType, Ontology.DATE_TIME)) {
				return DATE_TIME;
			} else {
				return INVALID;
			}
		}
	}
	
	private final String columnName;
	private final ValueType valueType;
	
	public DataTableColumn(String name, ValueType valueType) {
		super();
		this.columnName = name;
		this.valueType = valueType;
	}
	
	/**
	 * @brief Creates a new {@link DataTableColumn}.
	 * 
	 * name and value type are automatically initialized from the specified column in dataTable.
	 * The DataTableColumn does not keep a reference to dataTable.
	 */
	public DataTableColumn(DataTable dataTable, int columnIdx) {
		if (columnIdx >= 0 && columnIdx < dataTable.getColumnNumber()) {
			this.columnName = dataTable.getColumnName(columnIdx);
			if(dataTable.isDateTime(columnIdx)) {
				this.valueType = ValueType.DATE_TIME;
			} else if(dataTable.isNominal(columnIdx)) {
				this.valueType = ValueType.NOMINAL;
			} else if (dataTable.isNumerical(columnIdx)) {
				this.valueType = ValueType.NUMERICAL;
			} else {
				this.valueType = ValueType.INVALID;
			}
		} else {
			this.columnName = null;
			this.valueType = ValueType.INVALID;
		}
	}

	/**
	 * @return the {@link ValueType}
	 */
	public ValueType getValueType() {
		return valueType;
	}

	public boolean isNominal() {
		if(valueType == ValueType.NOMINAL) {
			return true;
		}
		return false;
	}
	
	public boolean isNumerical() {
		if(valueType == ValueType.NUMERICAL) {
			return true;
		}
		return false;
	}
	
	public boolean isDate() {
		if(valueType == ValueType.DATE_TIME) {
			return true;
		}
		return false;
	}


	/**
	 * @return the name
	 */
	public String getName() {
		return columnName;
	}


	@Override
	public String toString() {
		return getName();
	}


	@Override
	public boolean equals(Object obj) {
		if (obj == null) {
			return false;
		}
		
		if (!(obj instanceof DataTableColumn)) {
			return false;
		}
		
		DataTableColumn other = (DataTableColumn)obj;
		
		if (valueType != other.valueType) {
			return false;
		}
		
		if (  !(columnName == null ? other.columnName == null : columnName.equals(other.columnName))  ) {
			return false;
		}
		
		return true;
	}

	@Override
	public DataTableColumn clone() {
		return new DataTableColumn(getName(),getValueType());
	}

	/**
	 * Finds the column index for the column named columnName in dataTable,
	 * checks if that column in the data table is compatible with to settings
	 * valueType, and updates this.columnIdx.
	 * 
	 * If the column does not exist or is not compatible, the columnIdx is set to -1.
	 */
	public static int getColumnIndex(DataTable dataTable, String columnName, ValueType valueType) {
		int columnIdx = dataTable.getColumnIndex(columnName);
		if (columnIdx >= 0) {
			// check value type
			switch(valueType) {
			case NOMINAL:
				if (!dataTable.isNominal(columnIdx)) {
					columnIdx = -1;
				}
				break;
			case NUMERICAL:
				if (!dataTable.isNumerical(columnIdx)) {
					columnIdx = -1;
				}
				break;
			case DATE_TIME:
				if (!dataTable.isDateTime(columnIdx)) {
					columnIdx = -1;
				}
				break;
			case INVALID:
				// do nothing
				break;
			}
		}
		return columnIdx;
	}
	
	public boolean isValidForDataTable(DataTable dataTable) {
		int columnIdx = getColumnIndex(dataTable, columnName, valueType);
		return columnIdx >= 0 && valueType != ValueType.INVALID && columnName != null;
	}

	/**
	 * Finds the column index for the column named like dataTableColumn.getName in dataTable,
	 * checks if that column in the data table is compatible with to settings
	 * of dataTableColumn (value type etc.), and updates this.columnIdx.
	 * 
	 * If the column does not exist or is not compatible, the columnIdx is set to -1.
	 */
	public static int getColumnIndex(DataTable dataTable, DataTableColumn dataTableColumn) {
		return getColumnIndex(dataTable, dataTableColumn.getName(), dataTableColumn.getValueType());
	}
}