tablesortdecorator.java

《Java2图形设计卷II：Swing》配套光盘源码

import javax.swing.*;
import javax.swing.table.*;
import javax.swing.event.*;
import java.util.*;

public class TableSortDecorator extends TableModelDecorator 
								implements TableModelListener {
	int indexes[];

	public TableSortDecorator(TableModel m) {
		super(m);

		if(m == null || !(m instanceof AbstractTableModel))
			throw new IllegalArgumentException("bad model");

		m.addTableModelListener(this);
		allocate();
	}
	public Object getValueAt(int row, int column) {
		return super.getValueAt(indexes[row], column);
	}
	public void tableChanged(TableModelEvent e) {
		allocate();
	}
	public void sort(int column) {
		int rowCount = model.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);
				}
			}
		}
		fireTableStructureChanged();
	}
    public void swap(int i, int j) {
		int tmp = indexes[i];
		indexes[i] = indexes[j];
		indexes[j] = tmp;
	}
	public int compare(int i, int j, int column) {
		Object io = model.getValueAt(i,column);
		Object jo = model.getValueAt(j,column);

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

		for(int i=0; i < indexes.length; ++i) {
			indexes[i] = i;			
		}
	}
}