CTableSorter.java

/*
Copyright 2011-2016 Google 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.
*/
// TODO (jnewger): fix for BinDiff code base as well.

package com.google.security.zynamics.zylib.gui.tables;

import com.google.security.zynamics.zylib.general.comparators.LexicalComparator;

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.swing.Icon;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.SwingConstants;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumnModel;
import javax.swing.table.TableModel;


/**
 * CTableSorter is a decorator for TableModels; adding sorting functionality to a supplied
 * TableModel. CTableSorter does not store or copy the data in its TableModel; instead it maintains
 * a map from the row indexes of the view to the row indexes of the model. As requests are made of
 * the sorter (like getValueAt(row, col)) they are passed to the underlying model after the row
 * numbers have been translated via the internal mapping array. This way, the CTableSorter appears
 * to hold another copy of the table with the rows in a different order.
 * <p/>
 * CTableSorter registers itself as a listener to the underlying model, just as the JTable itself
 * would. Events recieved from the model are examined, sometimes manipulated (typically widened),
 * and then passed on to the CTableSorter's listeners (typically the JTable). If a change to the
 * model has invalidated the order of CTableSorter's rows, a note of this is made and the sorter
 * will resort the rows the next time a value is requested.
 * <p/>
 * When the tableHeader property is set, either by using the setTableHeader() method or the two
 * argument constructor, the table header may be used as a complete UI for CTableSorter. The default
 * renderer of the tableHeader is decorated with a renderer that indicates the sorting status of
 * each column. In addition, a mouse listener is installed with the following behavior:
 * <ul>
 * <li>Mouse-click: Clears the sorting status of all other columns and advances the sorting status
 * of that column through three values: {NOT_SORTED, ASCENDING, DESCENDING} (then back to NOT_SORTED
 * again).
 * <li>SHIFT-mouse-click: Clears the sorting status of all other columns and cycles the sorting
 * status of the column through the same three values, in the opposite order: {NOT_SORTED,
 * DESCENDING, ASCENDING}.
 * <li>CONTROL-mouse-click and CONTROL-SHIFT-mouse-click: as above except that the changes to the
 * column do not cancel the statuses of columns that are already sorting - giving a way to initiate
 * a compound sort.
 * </ul>
 * <p/>
 * This is a long overdue rewrite of a class of the same name that first appeared in the swing table
 * demos in 1997.
 * 
 * @author Philip Milne
 * @author Brendon McLean
 * @author Dan van Enckevort
 * @author Parwinder Sekhon
 * @version 2.0 02/27/04
 * @Deprecated CTableSorter should not be used anymore since standard classes, e.g. TableRowSorter,
 *             from the JDK replace this functionality in a much cleaner way.
 */
@Deprecated
public class CTableSorter extends AbstractTableModel {
  private static final long serialVersionUID = -6803591209710987100L;

  public static final int DESCENDING = -1;
  public static final int NOT_SORTED = 0;
  public static final int ASCENDING = 1;

  public static final Directive EMPTY_DIRECTIVE = new Directive(-1, NOT_SORTED);

  @SuppressWarnings("unchecked")
  public static final Comparator<Object> COMPARABLE_COMPARATOR = new Comparator<Object>() {
    @Override
    public int compare(final Object o1, final Object o2) {
      return ((Comparable<Object>) o1).compareTo(o2);
    }
  };

  protected TableModel tableModel;

  protected Row[] viewToModel;
  protected int[] modelToView;

  protected JTableHeader tableHeader;
  protected MouseListener mouseListener;
  protected TableModelListener tableModelListener;
  @SuppressWarnings("rawtypes")
  protected Map<Class, Comparator> columnComparators = new HashMap<Class, Comparator>();
  @SuppressWarnings("rawtypes")
  protected HashMap<Integer, Comparator> primaryColumnComparator =
      new HashMap<Integer, Comparator>();

  protected List<Directive> sortingColumns = new ArrayList<Directive>();

  public CTableSorter() {
    this.mouseListener = new MouseHandler();
    this.tableModelListener = new TableModelHandler();
  }

  public CTableSorter(final TableModel tableModel) {
    this();
    setTableModel(tableModel);
  }

  public CTableSorter(final TableModel tableModel, final JTableHeader tableHeader) {
    this();
    setTableHeader(tableHeader);
    setTableModel(tableModel);
  }

  private Directive getDirective(final int column) {
    for (int i = 0; i < sortingColumns.size(); i++) {
      final Directive directive = sortingColumns.get(i);
      if (directive.column == column) {
        return directive;
      }
    }
    return EMPTY_DIRECTIVE;
  }

  private Row[] getViewToModel() {
    if (viewToModel == null) {
      final int tableModelRowCount = tableModel.getRowCount();
      viewToModel = new Row[tableModelRowCount];
      for (int row = 0; row < tableModelRowCount; row++) {
        viewToModel[row] = new Row(row);
      }

      if (isSorting()) {
        Arrays.sort(viewToModel);
      }
    }
    return viewToModel;
  }

  private void sortingStatusChanged() {
    clearSortingState();
    fireTableDataChanged();
    if (tableHeader != null) {
      tableHeader.repaint();
    }
  }

  protected void cancelSorting() {
    sortingColumns.clear();
    sortingStatusChanged();
  }

  protected void clearSortingState() {
    viewToModel = null;
    modelToView = null;
  }

  @SuppressWarnings({"unchecked", "rawtypes"})
  protected Comparator<Object> getComparator(final int column) {
    final Class columnType = tableModel.getColumnClass(column);

    Comparator<Object> comparator = primaryColumnComparator.get(column);
    if (comparator != null) {
      return comparator;
    }

    comparator = columnComparators.get(columnType);
    if (comparator != null) {
      return comparator;
    }

    if (columnType.equals(String.class)) {
      return (Comparator) new LexicalComparator();
    }

    if (Comparable.class.isAssignableFrom(columnType)) {
      return COMPARABLE_COMPARATOR;
    }
    return (Comparator) new LexicalComparator();
  }

  protected Icon getHeaderRendererIcon(final int column, final int size) {
    final Directive directive = getDirective(column);
    if (directive == EMPTY_DIRECTIVE) {
      return null;
    }
    return new Arrow(directive.direction == DESCENDING, size, sortingColumns.indexOf(directive));
  }

  protected int[] getModelToView() {
    if (modelToView == null) {
      final int n = getViewToModel().length;
      modelToView = new int[n];
      for (int i = 0; i < n; i++) {
        modelToView[modelIndex(i)] = i;
      }
    }
    return modelToView;
  }

  @SuppressWarnings({"unchecked", "rawtypes"})
  @Override
  public Class getColumnClass(final int column) {
    return tableModel.getColumnClass(column);
  }

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

  @Override
  public String getColumnName(final int column) {
    return tableModel.getColumnName(column);
  }

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

  public int getSortingStatus(final int column) {
    return getDirective(column).direction;
  }

  public JTableHeader getTableHeader() {
    return tableHeader;
  }

  public TableModel getTableModel() {
    return tableModel;
  }

  @Override
  public Object getValueAt(final int row, final int column) {
    return tableModel.getValueAt(modelIndex(row), column);
  }

  @Override
  public boolean isCellEditable(final int row, final int column) {
    return tableModel.isCellEditable(modelIndex(row), column);
  }

  public boolean isSorting() {
    return sortingColumns.size() != 0;
  }

  // TableModel interface methods

  public int modelIndex(final int viewIndex) {
    if (viewIndex >= 0) {
      return getViewToModel()[viewIndex].modelIndex;
    }
    return 0;
  }

  public void setColumnComparator(@SuppressWarnings("rawtypes") final Class type,
      final Comparator<Object> comparator) {
    if (comparator == null) {
      columnComparators.remove(type);
    } else {
      columnComparators.put(type, comparator);
    }
  }

  public void setColumnComparator(final int column,
      @SuppressWarnings("rawtypes") final Comparator comparator) {
    if (comparator != null) {
      primaryColumnComparator.put(column, comparator);
    }
  }

  public void setSortingStatus(final int column, final int status) {
    final Directive directive = getDirective(column);
    if (directive != EMPTY_DIRECTIVE) {
      sortingColumns.remove(directive);
    }
    if (status != NOT_SORTED) {
      sortingColumns.add(new Directive(column, status));
    }
    sortingStatusChanged();
  }

  public void setTableHeader(final JTableHeader tableHeader) {
    if (this.tableHeader != null) {
      this.tableHeader.removeMouseListener(mouseListener);
      final TableCellRenderer defaultRenderer = this.tableHeader.getDefaultRenderer();
      if (defaultRenderer instanceof SortableHeaderRenderer) {
        this.tableHeader
            .setDefaultRenderer(((SortableHeaderRenderer) defaultRenderer).tableCellRenderer);
      }
    }
    this.tableHeader = tableHeader;
    if (this.tableHeader != null) {
      this.tableHeader.addMouseListener(mouseListener);
      this.tableHeader.setDefaultRenderer(new SortableHeaderRenderer(this.tableHeader
          .getDefaultRenderer()));
    }
  }

  public void setTableModel(final TableModel tableModel) {
    if (this.tableModel != null) {
      this.tableModel.removeTableModelListener(tableModelListener);
    }

    this.tableModel = tableModel;
    if (this.tableModel != null) {
      this.tableModel.addTableModelListener(tableModelListener);
    }

    clearSortingState();
    fireTableStructureChanged();
  }

  @Override
  public void setValueAt(final Object aValue, final int row, final int column) {
    tableModel.setValueAt(aValue, modelIndex(row), column);
  }

  public int viewIndex(final int modelIndex) {
    if (modelIndex >= 0) {
      return getModelToView()[modelIndex];
    }
    return 0;
  }

  // Helper classes

  private static class Arrow implements Icon {
    private final boolean descending;
    private final int size;
    private final int priority;

    public Arrow(final boolean descending, final int size, final int priority) {
      this.descending = descending;
      this.size = size;
      this.priority = priority;
    }

    @Override
    public int getIconHeight() {
      return size;
    }

    @Override
    public int getIconWidth() {
      return size;
    }

    @Override
    public void paintIcon(final Component c, final Graphics g, final int x, int y) {
      final Color color = c == null ? Color.GRAY : c.getBackground();
      // In a compound sort, make each succesive triangle 20%
      // smaller than the previous one.
      final int dx = (int) ((size / 2) * Math.pow(0.8, priority));
      final int dy = descending ? dx : -dx;
      // Align icon (roughly) with font baseline.
      y = y + ((5 * size) / 6) + (descending ? -dy : 0);
      final int shift = descending ? 1 : -1;
      g.translate(x, y);

      // Right diagonal.
      g.setColor(color.darker());
      g.drawLine(dx / 2, dy, 0, 0);
      g.drawLine(dx / 2, dy + shift, 0, shift);

      // Left diagonal.
      g.setColor(color.brighter());
      g.drawLine(dx / 2, dy, dx, 0);
      g.drawLine(dx / 2, dy + shift, dx, shift);

      // Horizontal line.
      if (descending) {
        g.setColor(color.darker().darker());
      } else {
        g.setColor(color.brighter().brighter());
      }
      g.drawLine(dx, 0, 0, 0);

      g.setColor(color);
      g.translate(-x, -y);
    }
  }

  private static class Directive {
    protected int column;
    protected int direction;

    public Directive(final int column, final int direction) {
      this.column = column;
      this.direction = direction;
    }
  }

  private class MouseHandler extends MouseAdapter {
    @Override
    public void mouseClicked(final MouseEvent e) {
      final JTableHeader h = (JTableHeader) e.getSource();
      final TableColumnModel columnModel = h.getColumnModel();
      final int viewColumn = columnModel.getColumnIndexAtX(e.getX());
      final int column = columnModel.getColumn(viewColumn).getModelIndex();
      if (column != -1) {
        int status = getSortingStatus(column);
        if (!e.isControlDown()) {
          cancelSorting();
        }
        // Cycle the sorting states through {NOT_SORTED, ASCENDING, DESCENDING} or
        // {NOT_SORTED, DESCENDING, ASCENDING} depending on whether shift is pressed.
        status = status + (e.isShiftDown() ? -1 : 1);
        status = ((status + 4) % 3) - 1; // signed mod, returning {-1, 0, 1}
        setSortingStatus(column, status);
      }
    }
  }

  // @SuppressWarnings("unchecked")
  private class Row implements Comparable<Object> {
    protected int modelIndex;

    public Row(final int index) {
      this.modelIndex = index;
    }

    @Override
    public int compareTo(final Object o) {
      final int row1 = modelIndex;
      final int row2 = ((Row) o).modelIndex;

      for (final Object element : sortingColumns) {
        final Directive directive = (Directive) element;
        final int column = directive.column;
        final Object o1 = tableModel.getValueAt(row1, column);
        final Object o2 = tableModel.getValueAt(row2, column);

        int comparison = 0;
        // Define null less than everything, except null.
        if ((o1 == null) && (o2 == null)) {
          comparison = 0;
        } else if (o1 == null) {
          comparison = -1;
        } else if (o2 == null) {
          comparison = 1;
        } else {
          comparison = getComparator(column).compare(o1, o2);
        }
        if (comparison != 0) {
          return directive.direction == DESCENDING ? -comparison : comparison;
        }
      }
      return 0;
    }
  }

  private class SortableHeaderRenderer implements TableCellRenderer {
    protected TableCellRenderer tableCellRenderer;

    public SortableHeaderRenderer(final TableCellRenderer tableCellRenderer) {
      this.tableCellRenderer = tableCellRenderer;
    }

    @Override
    public Component getTableCellRendererComponent(final JTable table, final Object value,
        final boolean isSelected, final boolean hasFocus, final int row, final int column) {
      final Component c =
          tableCellRenderer.getTableCellRendererComponent(table, value, isSelected, hasFocus, row,
              column);
      if (c instanceof JLabel) {
        final JLabel l = (JLabel) c;
        l.setHorizontalTextPosition(SwingConstants.LEFT);
        final int modelColumn = table.convertColumnIndexToModel(column);
        l.setIcon(getHeaderRendererIcon(modelColumn, l.getFont().getSize()));
      }
      return c;
    }
  }

  private class TableModelHandler implements TableModelListener {
    @Override
    public void tableChanged(final TableModelEvent e) {
      // If we're not sorting by anything, just pass the event along.
      if (!isSorting()) {
        clearSortingState();
        fireTableChanged(e);
        return;
      }

      // If the table structure has changed, cancel the sorting; the
      // sorting columns may have been either moved or deleted from
      // the model.
      if (e.getFirstRow() == TableModelEvent.HEADER_ROW) {
        cancelSorting();
        fireTableChanged(e);
        return;
      }

      // We can map a cell event through to the view without widening
      // when the following conditions apply:
      //
      // a) all the changes are on one row (e.getFirstRow() == e.getLastRow()) and,
      // b) all the changes are in one column (column != TableModelEvent.ALL_COLUMNS) and,
      // c) we are not sorting on that column (getSortingStatus(column) == NOT_SORTED) and,
      // d) a reverse lookup will not trigger a sort (modelToView != null)
      //
      // Note: INSERT and DELETE events fail this test as they have column == ALL_COLUMNS.
      //
      // The last check, for (modelToView != null) is to see if modelToView
      // is already allocated. If we don't do this check; sorting can become
      // a performance bottleneck for applications where cells
      // change rapidly in different parts of the table. If cells
      // change alternately in the sorting column and then outside of
      // it this class can end up re-sorting on alternate cell updates -
      // which can be a performance problem for large tables. The last
      // clause avoids this problem.
      final int column = e.getColumn();
      if ((e.getFirstRow() == e.getLastRow()) && (column != TableModelEvent.ALL_COLUMNS)
          && (getSortingStatus(column) == NOT_SORTED) && (modelToView != null)) {
        final int viewIndex = getModelToView()[e.getFirstRow()];
        fireTableChanged(new TableModelEvent(CTableSorter.this, viewIndex, viewIndex, column,
            e.getType()));
        return;
      }

      // Something has happened to the data that may have invalidated the row order.
      clearSortingState();
      fireTableDataChanged();
      return;
    }
  }
}