JTable 列宽自适应方法

import  java.awt.BorderLayout;
import  java.awt.Component;
import  java.awt.Dimension;
import  java.awt.event.WindowAdapter;
import  java.awt.event.WindowEvent;

import  javax.swing.JFrame;
import  javax.swing.JScrollPane;
import  javax.swing.JTable;
import  javax.swing.WindowConstants;
import  javax.swing.table.DefaultTableCellRenderer;
import  javax.swing.table.TableCellRenderer;
import  javax.swing.table.TableColumn;


public   class  FixTableColumnWidthFrame  extends  JFrame  {
    Object[] columnNames_  =   { " First Name " ,  " MI " ,  " Last Name " } ;

    Object[][] names_  =   {
                             {  " Lynn " ,  " M. " ,  " Seckinger "  } ,
                             {  " Carol " ,  " R. " ,  " Seckinger "  } ,
                             {  " Roy " ,  " D. " ,  " Martin "  } ,
                             {  " Bill " ,  " O. " ,  " Veryveryveryverylonglastname "  } ,
                             {  " Richard " ,  " A. " ,  " Tattersall "  } ,
                             {  " Philip " ,  " B. " ,  " Edwards "  } ,
                             {  " Moore " ,  " T. " ,  " Moore "  } ,
                            
                             //  shorten scrollbar grip with these 
                             {  " Lynn " ,  " M. " ,  " Seckinger "  } ,
                             {  " Carol " ,  " R. " ,  " Seckinger "  } ,
                             {  " Roy " ,  " D. " ,  " Martin "  } ,
                             {  " Bill " ,  " O. " ,  " Veryveryveryverylonglastname "  } ,
                             {  " Richard " ,  " A. " ,  " Tattersall "  } ,
                             {  " Philip " ,  " B. " ,  " Edwards "  } ,
                             {  " Moore " ,  " T. " ,  " Moore "  } ,
                        } ;
    JTable table_  =   new  JTable(names_, columnNames_);
     public  FixTableColumnWidthFrame()  {
        TableUtilities.fixTableColumnWidth(table_);
        JScrollPane scroll  =   new  JScrollPane(table_);
//         scroll.setPreferredSize(table_.getPreferredSize());
        getContentPane().add(scroll, BorderLayout.CENTER);
        pack();
    }
    
     public   static   void  main(String args[])  {
        FixTableColumnWidthFrame frame  =   new  FixTableColumnWidthFrame();
        frame.setTitle( " Setting Column Widths " );
        frame.pack();
        frame.show();
        frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
        frame.addWindowListener( new  WindowAdapter()  {
             public   void  windowClosed(WindowEvent e)  {
                System.exit( 0 );
            }
        } );
    }
}



class  TableUtilities  {
     public   static  Dimension fixTableColumnWidth(JTable table)  {
         int  MaxWidth  =   0 ;
         int  width  =   0 ;
         for  ( int  i  =   0 ; i  <  table.getColumnCount(); i ++ )  {
            TableColumn col  =  table.getColumn(table.getColumnName(i));
            width  =  getPreferredWidthForColumn(table, col);
            col.setMinWidth(width);
            col.setMaxWidth(width);
            MaxWidth  +=  width;
        }
         //  sizeColumnsToFit() must be called due to a JTable
         //  bug 
        table.sizeColumnsToFit( 0 );
        Dimension tableSize  =   new  Dimension(MaxWidth, table.getPreferredSize().height);
        table.setPreferredSize(tableSize);
         return  tableSize;
    }
     public   static   int  getPreferredWidthForColumn(JTable table, TableColumn col)  {
         int  hw  =  columnHeaderWidth(table, col),    //  hw = header width
            cw  =  widestCellInColumn(table, col);   //  cw = column width

         return  hw  >  cw  ?  hw : cw;
    }
     private   static   int  columnHeaderWidth(JTable table, TableColumn col)  {
        TableCellRenderer renderer  =  col.getHeaderRenderer();
         if  (renderer  ==   null )  {
            renderer  =   new  DefaultTableCellRenderer();
            ((DefaultTableCellRenderer)renderer).setText(col.getHeaderValue().toString());
        }
        Component comp  =  renderer.getTableCellRendererComponent(
                                      table, col.getHeaderValue(), 
                                       false ,  false ,  0 ,  0 );

         return  comp.getPreferredSize().width  +   2 ;
    }
     private   static   int  widestCellInColumn(JTable table, TableColumn col)  {
         int  c  =  col.getModelIndex(), width = 0 , maxw = 0 ;

         for ( int  r = 0 ; r  <  table.getRowCount();  ++ r)  {
            TableCellRenderer renderer  =  
                              table.getCellRenderer(r,c);

            Component comp  =  
                renderer.getTableCellRendererComponent(
                                      table, table.getValueAt(r,c), 
                                       false ,  false , r, c);

            width  =  comp.getPreferredSize().width  +   2 ;
            maxw  =  width  >  maxw  ?  width : maxw;
        }
         return  maxw;
    }
}