change.java

简单java成绩管理 提供添加 统计 修改功能

import java.awt.LayoutManager;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.DefaultTableModel;


public class change extends JPanel implements ActionListener{
	databasemanager dbm;
	
	JLabel label_num;
	JTextField textfield_num;
	JTable table;
	JScrollPane sc;
	DefaultTableModel tmodel;
	public change(databasemanager dbm){
		this.dbm=dbm;
		init();
	}
	public void init(){
		this.setLayout(null);
		
		{
			label_num=new JLabel("输入学号:");
			label_num.setFont(allset.font_label);
			label_num.setBounds(20, 10,60,22);
			this.add(label_num);
		}
		{
			textfield_num=new JTextField();
			textfield_num.setBounds(80,10,80,22);
			this.add(textfield_num);
			textfield_num.addActionListener(this);
		}

		sc=new JScrollPane();
		sc.setBounds(10,50,450,250);
		this.add(sc);
	}
	public static void main(String[] args) {
		JFrame f=new JFrame("dsf");
		f.setSize(480,350);
		
		
		change ce=new change(new databasemanager());
		f.getContentPane().add(ce);
		f.setVisible(true);
	}
	public String createsql(){
		String sql="select 学生信息表.学号,姓名,成绩表.课程代码,课程名称,成绩 "+
				"from 学生信息表 inner join 成绩表 on "+
				"学生信息表.学号=成绩表.学号 "+
				"inner join 课程信息表 on "+
				"成绩表.课程代码=课程信息表.课程代码 ";
		
		
		if(textfield_num.getText().length()>0){
			sql+="where 学生信息表.学号 like '"+textfield_num.getText()+"%'";
		}
		
		
		return sql;
	}
	public void actionPerformed(ActionEvent ae) {
		table=dbm.maketable(dbm.select(createsql()));
		table.setEnabled(true);
		sc.setViewportView(table);
		tmodel=(DefaultTableModel)table.getModel();
		tmodel.addTableModelListener(new TableModelListener(){
			public void tableChanged(TableModelEvent tme) {
				//System.out.println(tmodel.getColumnName(tme.getColumn()));
				//System.out.println(table.getValueAt(tme.getLastRow(),tme.getColumn()));
				//System.out.println(table.getValueAt(tme.getLastRow(),0));
				//System.out.println(tmodel.getColumnName(0));
				String sql="update 成绩表  set 成绩=? where 学号=? and 课程代码=?";
	
				String[] svar=new String[3];
				svar[0]=(String) table.getValueAt(tme.getLastRow(),tme.getColumn());
				svar[1]=(String) table.getValueAt(tme.getLastRow(),0);
				svar[2]=(String) table.getValueAt(tme.getLastRow(),2);
				
				int n=dbm.update(sql,svar);
				//System.out.println(svar[0]+":"+svar[1]+":"+svar[2]);
				//updata("update ")
				if(n==0){
					dbm.error("更新出错!");
					table.setValueAt("",tme.getLastRow(),tme.getColumn());
					
				}
			}
		});
	}

}