JDBC简单封装

public class JDBC8Util {
    
    private final Connection connection;
    private final Statement statement;

    private final String url;
    private final String username;
    private final String password;

    static {
    
        // 注册加载驱动，手动加载字节码文件到JVM中
        try {
    
            Class.forName("com.mysql.cj.jdbc.Driver");
        } catch (ClassNotFoundException e) {
    
            throw new RuntimeException(e);
        }
    }

    public JDBC8Util(String url, String username, String password) {
    
        this.url = url;
        this.username = username;
        this.password = password;
        try {
    
            this.connection = DriverManager.getConnection(url, username, password);
            this.statement = connection.createStatement();
        } catch (SQLException e) {
    
            throw new RuntimeException(e);
        }
    }

    public static JDBC8Util createJDBC8(String url, String username, String password) {
    
        return new JDBC8Util(url, username, password);
    }

    public int update(String sql) throws SQLException {
    
        return statement.executeUpdate(sql);
    }

    public int insert(String sql) throws SQLException {
    
        return statement.executeUpdate(sql);
    }

    public int delete(String sql) throws SQLException {
    
        return statement.executeUpdate(sql);
    }

    public ResultSet query(String sql) throws SQLException {
    
        return statement.executeQuery(sql);
    }

    public void close() throws SQLException {
    
        if (statement != null)
            statement.close();
        if (connection != null)
            connection.close();
    }

    public Connection getConnection() {
    
        return connection;
    }

    public Statement getStatement() {
    
        return statement;
    }

    public String getUrl() {
    
        return url;
    }

    public String getUsername() {
    
        return username;
    }

    public String getPassword() {
    
        return password;
    }
}

public class JDBCTest {
    
    public static void main(String[] args) {
    
        String url = "jdbc:mysql://localhost:3306/work0724?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=false";
        String username = "root";
        String password = "admin";
        JDBC8Util jdbc8Util = JDBC8Util.createJDBC8(url, username, password);
        try {
    
            // 插入
            String insertSql = "insert into dept (name,room,phone) value ('市场部','206','11111111');";
            int insert = jdbc8Util.insert(insertSql);
            System.out.println("插入 insert\t" + insert);
            // 修改
            String updateSql = "update dept set name='财务部',room='102',phone='12345566' where id=1";
            int update = jdbc8Util.update(updateSql);
            System.out.println("修改 update\t" + update);
            // 删除
            String deleteSql = "delete from dept where id=3";
            int delete = jdbc8Util.delete(deleteSql);
            System.out.println("删除 delete\t" + delete);
        } catch (SQLException e) {
    
            throw new RuntimeException(e);
        }
        try {
    
            jdbc8Util.close();
            System.out.println("操作完成，关闭数据库连接");
        } catch (SQLException e) {
    
            throw new RuntimeException(e);
        }
    }
}