Java는 온라인 시험 시스템에서 시험 점수 곡선 분석을 구현합니다.

// 导入数据库相关的包
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class ScoreAnalysis {
    public static void main(String[] args) {
        // 连接数据库
        String url = "jdbc:mysql://localhost:3306/exam_db";
        String user = "root";
        String password = "123456";
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;
        
        try {
            Class.forName("com.mysql.jdbc.Driver");
            connection = DriverManager.getConnection(url, user, password);
            statement = connection.createStatement();
            
            // 查询学生成绩数据
            String sql = "SELECT id, score FROM exam_score";
            resultSet = statement.executeQuery(sql);
            
            while(resultSet.next()){
                int id = resultSet.getInt("id");
                int score = resultSet.getInt("score");
                // 处理每个学生的成绩，进行成绩曲线分析
                // ...
            }
            
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            try {
                if(resultSet != null){
                    resultSet.close();
                }
                if(statement != null){
                    statement.close();
                }
                if(connection != null){
                    connection.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}

import java.util.HashMap;
import java.util.Map;

public class ScoreAnalysis {
    public static void main(String[] args) {
        // 假设成绩范围为0-100，设置步长为10
        int limit = 10;
        
        // 定义一个Map用于存储分数段和学生人数的对应关系
        Map<Integer, Integer> scoreMap = new HashMap<>();
        
        // 初始化分数段和学生人数的对应关系
        for (int i = 0; i <= 10; i++) {
            scoreMap.put(i, 0);
        }
        
        // 遍历学生成绩数据，根据分数段进行统计
        while(resultSet.next()){
            int id = resultSet.getInt("id");
            int score = resultSet.getInt("score");
            
            // 计算学生得分所属的分数段
            int section = score / limit;
            
            // 更新分数段对应的学生人数
            scoreMap.put(section, scoreMap.get(section) + 1);
        }
        
        // 输出分数段和学生人数的统计结果
        for (int i = 0; i <= 10; i++) {
            System.out.println("分数段 " + i * limit + "-" + (i + 1) * limit + ": " + scoreMap.get(i));
        }
        
        // 根据统计结果，画出成绩曲线
        // ...
    }
}

import org.jfree.chart.ChartFrame;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.data.category.DefaultCategoryDataset;

public class ScoreAnalysis {
    public static void main(String[] args) {
        // ...省略前面的代码
        
        // 根据统计结果，画出成绩曲线
        DefaultCategoryDataset dataset = new DefaultCategoryDataset();
        for (int i = 0; i <= 10; i++) {
            dataset.addValue(scoreMap.get(i), "人数", i * limit + "-" + (i+1) * limit);
        }
        
        // 创建柱状图
        JFreeChart chart = ChartFactory.createBarChart("成绩曲线分析", "分数段", "学生人数", dataset);
        
        // 创建图表窗口并显示
        ChartFrame frame = new ChartFrame("成绩曲线分析", chart);
        frame.pack();
        frame.setVisible(true);
        
        // ...省略后续的代码
    }
}