bookqueryframe.java

图书管理系统

/**********************************
 * FileName:BookQueryFrame.java
 * Function:根据书名查询图书
 * Time:2004 1.8
 *********************************/

import java.io.*;
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.table.*;
import java.sql.*; 

class BookQueryFrame extends Frame implements ActionListener 
{   
	Panel topPanel = new Panel ();
	Label lbBookName = new Label ("书名");
	Label lbResult = new Label ("结果显示");
	TextField tfBookName = new TextField (30);
	TextField tfResult = new TextField (20);
	Button butQuery = new Button("查询");
	Button butClear = new Button ("清空");
	Button butExit = new Button ("退出");
	JTable tbBQResult;
	JScrollPane tbPane1;
	private Vector vect = new Vector ();
	String labels[] = {"书本ID","书名","作者","出版社","出版日期"};
    ConDB conUserQuery= new ConDB();
	private int bookY =0;

	BookQueryFrame()
	{
		setTitle("图书查询窗口");
		BorderLayout gbLayout = new BorderLayout();
		setLayout(gbLayout);
		tbBQResult = new JTable(tm);
	    tbBQResult.setToolTipText("图书记录");
	    tbBQResult.setCellSelectionEnabled(false);
	    tbBQResult.setShowVerticalLines(true);
	    tbBQResult.setShowHorizontalLines(true);
	    tbPane1 = new  JScrollPane(tbBQResult);
		
		
		//面板topPanel设置
		topPanel.setLayout(new GridLayout());
	    topPanel.add(lbBookName);
	    topPanel.add(tfBookName);
	    topPanel.add(butQuery);
		topPanel.add(butClear);
	    topPanel.add(butExit);
		topPanel.add(lbResult);
		topPanel.add(tfResult);
		tfResult.setEditable (false);
	   
	    add("North",topPanel);
	    add("Center",tbPane1);
		butQuery.addActionListener (this);
		butClear.addActionListener (this);
	    butExit.addActionListener (this);
	    this.setVisible (true);
	    this.setSize(900,600);
	    this.setLocation (100,100);	
		
	    addWindowListener(new WindowAdapter() 
	   {
		  public void windowClosing(WindowEvent e) 
        	{
               System.exit (0);
        	}
      	 });
		openDB();
	 
	}//end of new UserQueryFrame()
	
	
	//设定数据
        //声明一个类AbstractTableModel对象
        //实现AbstractTableModel对象tm中的方法
      AbstractTableModel tm= new AbstractTableModel() 
		{
			//取得表格列数
			public int getColumnCount() { return labels.length; }
            //取得表格行数
			public int getRowCount() { return vect.size();}
            //取得单元格中的属性值
			public Object getValueAt(int arow, int acol) 
			{ 
				Vector row = (Vector)vect.elementAt(arow);
	            return row.elementAt(acol);
			 }
			//设置表格列名
		   public  String getColumnName(int column)
			{
			   if (labels[column] != null) 
			   {
            	  return labels[column];
        		}
			
			   else 
			  {
				   return "";
        		
			   }
		    }
			
			//数据模型不可编辑,该方法设置为空
			public void setValueAt(Object value,int arow,int acol){  }
	
		    //取得列所属对象类
			public  Class getColumnClass(int column)
			{
      	        int type;
      	        try {
      	            type = conUserQuery.rs.getMetaData().getColumnType(column+1);
      	        }
      	        catch (SQLException e) {
      	            return super.getColumnClass(column);
      	        }
      
      	        switch(type) {
      	        case Types.CHAR:
      	        case Types.VARCHAR:
      	        case Types.LONGVARCHAR:
      	            return String.class;
      
      	        case Types.BIT:
      	            return Boolean.class;
      
      	        case Types.TINYINT:
      	        case Types.SMALLINT:
      	        case Types.INTEGER:
      	            return Integer.class;
      
      	        case Types.BIGINT:
      	            return Long.class;
      
      	        case Types.FLOAT:
      	        case Types.DOUBLE:
      	            return Double.class;
      
      	        case Types.DATE:
      	            return java.sql.Date.class;
      
      	        default:
      	            return Object.class;
      	        }
      	    }
		  //设置单元格不可编辑,为缺省实现
		  public  boolean isCellEditable(int row,int column)
		  {
			return false;
		  }

			
		};//end of new AbstractTableModel()  
	
	private void bookQuery()
	{
 	    String bookName = tfBookName.getText ();
		try{
		    
			ResultSetMetaData rsmd = conUserQuery.rs.getMetaData();
	        conUserQuery.stm = conUserQuery.con.createStatement();
 
	 	   if(bookName.compareTo ("") ==0)
			  conUserQuery.rs = conUserQuery.stm.executeQuery("select * from book");
		   else
			conUserQuery.rs = conUserQuery.stm.executeQuery("select * from book where bookname ='"+bookName+"'");
		  
		   //初始化向量对象
		   vect.removeAllElements();
		  //更新表格内容
		  tm.fireTableStructureChanged();
        
	      while(conUserQuery.rs.next())
			  {
				  Vector rec_vector = new Vector();
				  for(int i =1; i<=rsmd.getColumnCount(); i++)
				  {
				//从结果集中取数据放入向量rec_vector中
				     rec_vector.addElement(conUserQuery.rs.getObject(i));
			      }
			
			   //向量rec_vector加入向量vect中
		    	vect.addElement(rec_vector);
				bookY =1;
		        
		     }
		
		//更新表格,显示向量vect的内容		
		tm.fireTableStructureChanged();
		//查询完成后,关闭该SQL
		conUserQuery.stm.close();
		//重新执行SQL
		openDB();

   	 } 
	catch(Exception e)
		{
		   System.out.print("Error in Query Data." + e);
   		   System.exit(1); 
   	   }
  }// end of private void dataQuery()


   //打开表
   private void openDB() 
   {
	   try
	   {
		   conUserQuery.stm = conUserQuery.con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                      ResultSet.CONCUR_UPDATABLE);
		   conUserQuery.rs = conUserQuery.stm.executeQuery("select * from book");
		   conUserQuery.rs.first();
 
	   }
	   catch(Exception e)
	   {
		   System.out.print("Error in open table." + e);
		   System.exit(1); 
   	
	   }
   } // end of private void openDB() 
	
	public void actionPerformed(ActionEvent e)
	{
		
		if(e.getActionCommand () == "查询")
		{	
			bookQuery();
		    if(bookY ==0)
				tfResult.setText ("输入的书名不存在");
			bookY=0;
		}
		if(e.getActionCommand ()=="清空")
		{
			tfBookName.setText ("");
			tfResult.setText ("");
		}
	    if(e.getActionCommand () == "退出")
			dispose ();
	}
}