tablebubblesortdecorator.java

来自「java的23中设计模式的代码实现」· Java 代码 · 共 62 行

import javax.swing.table.TableModel;
import javax.swing.event.TableModelEvent;

public class TableBubbleSortDecorator extends TableSortDecorator {
   // The lone constructor must be passed a reference to a
   // TableModel. This class decorates that model with additional
   // sorting functionality.
   public TableBubbleSortDecorator(TableModel model) {
      super(model);
      allocate();
   }

   // tableChanged is defined in TableModelListener, which
   // is implemented by TableSortDecorator.
   public void tableChanged(TableModelEvent e) {
      allocate();   
   }

   // Two TableModel methods are overridden from
   // TableModelDecorator ...
   public Object getValueAt(int row, int column) {
      return getRealModel().getValueAt(indexes[row], column);
   }
   public void setValueAt(Object aValue, int row, int column) {
      getRealModel().setValueAt(aValue, indexes[row], column);
   }

   // The following methods perform the bubble sort ...

   public void sort(int column) {
      int rowCount = getRowCount();

      for(int i=0; i < rowCount; i++) {
         for(int j = i+1; j < rowCount; j++) {
            if(compare(indexes[i], indexes[j], column) < 0) {
               swap(i,j);
            }
         }
      }
   }
   private void swap(int i, int j) {
      int tmp = indexes[i];
      indexes[i] = indexes[j];
      indexes[j] = tmp;
   }
   private int compare(int i, int j, int column) {
      TableModel realModel = getRealModel();
      Object io = realModel.getValueAt(i,column);
      Object jo = realModel.getValueAt(j,column);

      int c = jo.toString().compareTo(io.toString());
      return (c < 0) ? -1 : ((c > 0) ? 1 : 0);
   }
   private void allocate() {
      indexes = new int[getRowCount()];
      for(int i=0; i < indexes.length; ++i) {
         indexes[i] = i;         
      }
   }
   private int indexes[];
}