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	/*
	* Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing.table;

	import java.text.Collator;
	import java.util.*;
	import javax.swing.DefaultRowSorter;
	import javax.swing.RowFilter;
	import javax.swing.SortOrder;

	/**
	* An implementation of <code>RowSorter</code> that provides sorting
	* and filtering using a <code>TableModel</code>.
	* The following example shows adding sorting to a <code>JTable</code>:
	* <pre>
	* TableModel myModel = createMyTableModel();
	* JTable table = new JTable(myModel);
	* table.setRowSorter(new TableRowSorter(myModel));
	* </pre>
	* This will do all the wiring such that when the user does the appropriate
	* gesture, such as clicking on the column header, the table will
	* visually sort.
	* <p>
	* <code>JTable</code>'s row-based methods and <code>JTable</code>'s
	* selection model refer to the view and not the underlying
	* model. Therefore, it is necessary to convert between the two. For
	* example, to get the selection in terms of <code>myModel</code>
	* you need to convert the indices:
	* <pre>
	* int[] selection = table.getSelectedRows();
	* for (int i = 0; i < selection.length; i++) {
	* selection[i] = table.convertRowIndexToModel(selection[i]);
	* }
	* </pre>
	* Similarly to select a row in <code>JTable</code> based on
	* a coordinate from the underlying model do the inverse:
	* <pre>
	* table.setRowSelectionInterval(table.convertRowIndexToView(row),
	* table.convertRowIndexToView(row));
	* </pre>
	* <p>
	* The previous example assumes you have not enabled filtering. If you
	* have enabled filtering <code>convertRowIndexToView</code> will return
	* -1 for locations that are not visible in the view.
	* <p>
	* <code>TableRowSorter</code> uses <code>Comparator</code>s for doing
	* comparisons. The following defines how a <code>Comparator</code> is
	* chosen for a column:
	* <ol>
	* <li>If a <code>Comparator</code> has been specified for the column by the
	* <code>setComparator</code> method, use it.
	* <li>If the column class as returned by <code>getColumnClass</code> is
	* <code>String</code>, use the <code>Comparator</code> returned by
	* <code>Collator.getInstance()</code>.
	* <li>If the column class implements <code>Comparable</code>, use a
	* <code>Comparator</code> that invokes the <code>compareTo</code>
	* method.
	* <li>If a <code>TableStringConverter</code> has been specified, use it
	* to convert the values to <code>String</code>s and then use the
	* <code>Comparator</code> returned by <code>Collator.getInstance()</code>.
	* <li>Otherwise use the <code>Comparator</code> returned by
	* <code>Collator.getInstance()</code> on the results from
	* calling <code>toString</code> on the objects.
	* </ol>
	* <p>
	* In addition to sorting <code>TableRowSorter</code> provides the ability
	* to filter. A filter is specified using the <code>setFilter</code>
	* method. The following example will only show rows containing the string
	* "foo":
	* <pre>
	* TableModel myModel = createMyTableModel();
	* TableRowSorter sorter = new TableRowSorter(myModel);
	* sorter.setRowFilter(RowFilter.regexFilter(".foo."));
	* JTable table = new JTable(myModel);
	* table.setRowSorter(sorter);
	* </pre>
	* <p>
	* If the underlying model structure changes (the
	* <code>modelStructureChanged</code> method is invoked) the following
	* are reset to their default values: <code>Comparator</code>s by
	* column, current sort order, and whether each column is sortable. The default
	* sort order is natural (the same as the model), and columns are
	* sortable by default.
	* <p>
	* <code>TableRowSorter</code> has one formal type parameter: the type
	* of the model. Passing in a type that corresponds exactly to your
	* model allows you to filter based on your model without casting.
	* Refer to the documentation of <code>RowFilter</code> for an example
	* of this.
	* <p>
	* <b>WARNING:</b> <code>DefaultTableModel</code> returns a column
	* class of <code>Object</code>. As such all comparisons will
	* be done using <code>toString</code>. This may be unnecessarily
	* expensive. If the column only contains one type of value, such as
	* an <code>Integer</code>, you should override <code>getColumnClass</code> and
	* return the appropriate <code>Class</code>. This will dramatically
	* increase the performance of this class.
	*
	* @param <M> the type of the model, which must be an implementation of
	* <code>TableModel</code>
	* @see javax.swing.JTable
	* @see javax.swing.RowFilter
	* @see javax.swing.table.DefaultTableModel
	* @see java.text.Collator
	* @see java.util.Comparator
	* @since 1.6
	*/
	public class TableRowSorter<M extends TableModel> extends DefaultRowSorter<M, Integer> {
	/**
	* Comparator that uses compareTo on the contents.
	*/
	private static final Comparator COMPARABLE_COMPARATOR =
	new ComparableComparator();

	/**
	* Underlying model.
	*/
	private M tableModel;

	/**
	* For toString conversions.
	*/
	private TableStringConverter stringConverter;


	/**
	* Creates a <code>TableRowSorter</code> with an empty model.
	*/
	public TableRowSorter() {
	this(null);
	}

	/**
	* Creates a <code>TableRowSorter</code> using <code>model</code>
	* as the underlying <code>TableModel</code>.
	*
	* @param model the underlying <code>TableModel</code> to use,
	* <code>null</code> is treated as an empty model
	*/
	public TableRowSorter(M model) {
	setModel(model);
	}

	/**
	* Sets the <code>TableModel</code> to use as the underlying model
	* for this <code>TableRowSorter</code>. A value of <code>null</code>
	* can be used to set an empty model.
	*
	* @param model the underlying model to use, or <code>null</code>
	*/
	public void setModel(M model) {
	tableModel = model;
	setModelWrapper(new TableRowSorterModelWrapper());
	}

	/**
	* Sets the object responsible for converting values from the
	* model to strings. If non-<code>null</code> this
	* is used to convert any object values, that do not have a
	* registered <code>Comparator</code>, to strings.
	*
	* @param stringConverter the object responsible for converting values
	* from the model to strings
	*/
	public void setStringConverter(TableStringConverter stringConverter) {
	this.stringConverter = stringConverter;
	}

	/**
	* Returns the object responsible for converting values from the
	* model to strings.
	*
	* @return object responsible for converting values to strings.
	*/
	public TableStringConverter getStringConverter() {
	return stringConverter;
	}

	/**
	* Returns the <code>Comparator</code> for the specified
	* column. If a <code>Comparator</code> has not been specified using
	* the <code>setComparator</code> method a <code>Comparator</code>
	* will be returned based on the column class
	* (<code>TableModel.getColumnClass</code>) of the specified column.
	* If the column class is <code>String</code>,
	* <code>Collator.getInstance</code> is returned. If the
	* column class implements <code>Comparable</code> a private
	* <code>Comparator</code> is returned that invokes the
	* <code>compareTo</code> method. Otherwise
	* <code>Collator.getInstance</code> is returned.
	*
	* @throws IndexOutOfBoundsException {@inheritDoc}
	*/
	public Comparator<?> getComparator(int column) {
	Comparator comparator = super.getComparator(column);
	if (comparator != null) {
	return comparator;
	}
	Class columnClass = getModel().getColumnClass(column);
	if (columnClass == String.class) {
	return Collator.getInstance();
	}
	if (Comparable.class.isAssignableFrom(columnClass)) {
	return COMPARABLE_COMPARATOR;
	}
	return Collator.getInstance();
	}

	/**
	* {@inheritDoc}
	*
	* @throws IndexOutOfBoundsException {@inheritDoc}
	*/
	protected boolean useToString(int column) {
	Comparator comparator = super.getComparator(column);
	if (comparator != null) {
	return false;
	}
	Class columnClass = getModel().getColumnClass(column);
	if (columnClass == String.class) {
	return false;
	}
	if (Comparable.class.isAssignableFrom(columnClass)) {
	return false;
	}
	return true;
	}

	/**
	* Implementation of DefaultRowSorter.ModelWrapper that delegates to a
	* TableModel.
	*/
	private class TableRowSorterModelWrapper extends ModelWrapper<M,Integer> {
	public M getModel() {
	return tableModel;
	}

	public int getColumnCount() {
	return (tableModel == null) ? 0 : tableModel.getColumnCount();
	}

	public int getRowCount() {
	return (tableModel == null) ? 0 : tableModel.getRowCount();
	}

	public Object getValueAt(int row, int column) {
	return tableModel.getValueAt(row, column);
	}

	public String getStringValueAt(int row, int column) {
	TableStringConverter converter = getStringConverter();
	if (converter != null) {
	// Use the converter
	String value = converter.toString(
	tableModel, row, column);
	if (value != null) {
	return value;
	}
	return "";
	}

	// No converter, use getValueAt followed by toString
	Object o = getValueAt(row, column);
	if (o == null) {
	return "";
	}
	String string = o.toString();
	if (string == null) {
	return "";
	}
	return string;
	}

	public Integer getIdentifier(int index) {
	return index;
	}
	}


	private static class ComparableComparator implements Comparator {
	@SuppressWarnings("unchecked")
	public int compare(Object o1, Object o2) {
	return ((Comparable)o1).compareTo(o2);
	}
	}
	}

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