成绩管理系统java+mySQL(8)

你的姓名——《Java语言》课程期末作业

text.setText(\); String s=\;

if(subject.getSelectedItem().equals(\语文\)) s=\;

else if(subject.getSelectedItem().equals(\英语\)) s=\;

else if(subject.getSelectedItem().equals(\数学\)) s=\; else

JOptionPane.showMessageDialog(null, \找不到该科目\, \,

JOptionPane.INFORMATION_MESSAGE); if(s.equals(\)){ } else try{

Connection con=DataBaseCreate.getConnection(); Statement

sql=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);

ResultSet rs=sql.executeQuery(\+s+\student\);

rs.last();

//获取数据总行数

int row=rs.getRow();

float score[]=new float[row]; rs.first(); int i=0;

//将指定科目成绩放入数组 while(i

score[i]=rs.getFloat(s); rs.next(); i+=1; }

//快速排序

Arrays.sort(score);

text.setLineWrap(true); //激活自动换行功能 text.setWrapStyleWord(true); // 激活断行不断字功能

text.append(subject.getSelectedItem()+\成绩排名:\\r\\n\);

text.append(\排名 姓名 成绩 \\r\\n\);

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你的姓名——《Java语言》课程期末作业

ResultSet rs1; int rank=1;

float ave=0; //计算平均分 for(int j=row-1;j>=0;--j){

rs1=sql.executeQuery(\* from student where \+s+\+score[j]+\); rs1.next();

text.append(rank+\\+rs1.getString(\)+\

+rs1.getFloat(s)+\); rank+=1;

ave+=rs1.getFloat(s); }

ave=ave/(rank-1);

text.append(subject.getSelectedItem()+\平均成绩: \+ave+\);

}catch(java.lang.ClassNotFoundException err){ JOptionPane.showMessageDialog(null, err.getMessage(), \,

JOptionPane.INFORMATION_MESSAGE); }catch (SQLException ex){

JOptionPane.showMessageDialog(null, ex.getMessage(), \, JOptionPane.INFORMATION_MESSAGE); } }

else if(e.getActionCommand()==\取消\){ setVisible(false); }

else if(e.getActionCommand()==\保存\){

TxtSave save=new TxtSave(text.getText(),\按\+subject.getSelectedItem()+\成绩排名\); } } }

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

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你的姓名——《Java语言》课程期末作业

import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Arrays;

import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTextArea;

public class TotalScoreRanking extends IndexOrManage implements ActionListener{

public TotalScoreRanking(){

super(); //注册监听

b1.addActionListener(this); b2.addActionListener(this); b3.addActionListener(this);

pack();

setVisible(true); }

@Override

public void actionPerformed(ActionEvent e) { // TODO 自动生成的方法存根

if(e.getActionCommand()==\显示\){ b1.setEnabled(false); try{

Connection con=DataBaseCreate.getConnection(); Statement

sql=con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_UPDATABLE);

ResultSet rs=sql.executeQuery(\student\);

rs.last();

//获取数据总行数

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你的姓名——《Java语言》课程期末作业

int row=rs.getRow();

float score[]=new float[row]; rs.first(); int i=0;

//将总分成绩放入数组 while(i

score[i]=rs.getFloat(\); rs.next(); i+=1; }

//快速排序

Arrays.sort(score);

text.setLineWrap(true); //激活自动换行功能 text.setWrapStyleWord(true); // 激活断行不断字功能

text.append(\总分成绩排名:\\r\\n\);

text.append(\排名 姓名 总分 \\r\\n\);

ResultSet rs1; int rank=1; float ave=0;

for(int j=row-1;j>=0;--j){ //通过总分查找数据

rs1=sql.executeQuery(\* from student where Total like '%\+score[j]+\); rs1.next();

text.append(rank+\\+rs1.getString(\)+\

+rs1.getFloat(\)+\); ave+=rs1.getFloat(\); rank+=1; }

ave=ave/(rank-1);

text.append(\平均总分: \+ave+\);

}catch(java.lang.ClassNotFoundException err){ JOptionPane.showMessageDialog(null, err.getMessage(), \,

JOptionPane.INFORMATION_MESSAGE); }catch (SQLException ex){

JOptionPane.showMessageDialog(null, ex.getMessage(), \, JOptionPane.INFORMATION_MESSAGE);

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你的姓名——《Java语言》课程期末作业

} }

else if(e.getActionCommand()==\取消\){ setVisible(false); }

else if(e.getActionCommand()==\保存\){

TxtSave save=new TxtSave(text.getText(),\按总分排名\); }

}

}

import java.awt.BorderLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement;

import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JFrame; import javax.swing.JLabel;

import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTextArea;

public class PassStudents extends IndexOrManage implements ActionListener{

String[] subjects={\,\语文\,\英语\,\数学\}; JComboBox subject=new JComboBox(subjects); JLabel la=new JLabel(\选择查询科目\);

public PassStudents(){ super(); p1.add(la);

p1.add(subject); //注册监听

b1.addActionListener(this); b2.addActionListener(this);

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