diff --git "a/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/BigDecimal.java" "b/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/BigDecimal.java" deleted file mode 100644 index 0035b85497fbad9b7681b2020fff534eb25ce1e5..0000000000000000000000000000000000000000 --- "a/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/BigDecimal.java" +++ /dev/null @@ -1,36 +0,0 @@ -package com.java.minxi.java_20240516.java_2302_李新炜_2344310245; - -public class BigDecimal { - public static void main(String[] args) { - // 编写一个程序，使用字符串构造函数创建一个 `BigDecimal` 对象。 - BigDecimal bg1 = new BigDecimal("1.1"); - System.out.println(bg1.toString()); -// 实现一个方法，接受两个 `BigDecimal` 对象作为参数，执行加、减、乘、除运算。 - BigDecimal a = new BigDecimal(3); - BigDecimal b = new BigDecimal(2); - a = a.add(b); - System.out.println(a); - a = a.subtract(b); - System.out.println(a); - a = a.multiply(b); - System.out.println(a); - a = a.divide(b); - System.out.println(a); -// 舍入操作 -// - 编写一个程序，对一个 `BigDecimal` 对象执行舍入操作，指定舍入模式和精度。 - BigDecimal number=new BigDecimal("3.1415926"); - BigDecimal result=number.setScale(2, RoundingMode.DOWN); - System.out.println(result); -//比较 BigDecimal 对象值 -// - 创建一个方法，比较两个 `BigDecimal` 对象的值是否相等。 - BigDecimal b1=new BigDecimal("12"); - BigDecimal b2=new BigDecimal("45"); - System.out.println(b1.equals(b2)); - -// - 创建一个方法，比较两个 `BigDecimal` 对象的值大小。 - BigDecimal k=new BigDecimal("2"); - BigDecimal m=new BigDecimal("6"); - boolean bool=a.compareTo(b)==0; - System.out.println("比较结果为：a等于b:"+bool); - } -} diff --git "a/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Math.java" "b/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Math.java" deleted file mode 100644 index 9d9917f29252b473b11749dcdcb8d9fdec5322e4..0000000000000000000000000000000000000000 --- "a/work/com/java/minxi/java_20240516/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Math.java" +++ /dev/null @@ -1,41 +0,0 @@ -package com.java.minxi.java_20240516.java_2302_李新炜_2344310245; - -import java.util.Scanner; - -public class Math { - //编写一个程序，接受一个用户输入的数字，然后输出该数字的绝对值。 - public static void main(StringTest[] args) { - Scanner scanner = new Scanner(System.in); - System.out.println("请输入一个数字"); - int a= scanner.nextInt(); - System.out.println("绝对值为："+Math.abs(a)); - - //使用 `Math.random()` 方法生成一个 0 到 1 之间的随机数，并将其乘以一个用户指定的最大值。 - System.out.println("请输入一个浮点数"); - double b= scanner.nextDouble(); - System.out.println("四舍五入后为："+Math.rint(b)); - - //创建一个方法，接受三个整数作为参数，返回这三个整数中的最小值和最大值 - int c=1; - int d=2; - int e=3; - System.out.println(Math.max(c,Math.max(d,e))); - System.out.println(Math.min(c,Math.max(d,e))); - - //使用 `Math.random()` 方法生成一个 0 到 1 之间的随机数，并将其乘以一个用户指定的最大值。 - System.out.println("请输入一个最大值"); - int max= scanner.nextInt(); - double random=Math.random(); - System.out.println(random); - System.out.println(random*max); - - //创建一个方法，接受一个整数数组，并返回数组的平均值。 - int[] arr={10,20,30,40,50}; - int sum=0; - for (int i = 0; i < arr.length; i++) { - sum=sum+arr[i]; - } - double avarage=sum/arr.length; - System.out.println(avarage); - } -} diff --git "a/work/com/java/minxi/java_20240524/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Wyl.java" "b/work/com/java/minxi/java_20240524/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Wyl.java" new file mode 100644 index 0000000000000000000000000000000000000000..6e1c6d098629571ead939efb030fc137550254ee --- /dev/null +++ "b/work/com/java/minxi/java_20240524/java_2302_\346\235\216\346\226\260\347\202\234_2344310245/Wyl.java" @@ -0,0 +1,89 @@ +package com.java.minxi.java_20240524.java_2302_李新炜_2344310245; + +import java.sql.*; + +public class Wyl { + public static void main(String[] args)throws Exception { + wylrz(); + } + public static void wylrz()throws Exception{ + Connection connection = null; + Statement statement = null; + try { + Class.forName("com.mysql.cj.jdbc.Driver"); + + String url = "jdbc:mysql://localhost:3306/student?"+"serverTimezone=Asia/shanghai"; + String username = "root"; + String password = "123456"; + Connection conn = DriverManager.getConnection(url,username,password); + + String sql = "SELECT * FROM teacher_info"; + + Statement stmt = conn.createStatement(); + + int rs = stmt.executeUpdate(sql); + if(rs > 0){ + System.out.println("执行成功"); + }else { + System.out.println("执行失败"); + } + } catch (Exception e) { + e.printStackTrace(); + }finally { + try { + statement.close(); + connection.close(); + }catch (Exception e){ + e.printStackTrace(); + } + } + } + public static void wylrz2()throws Exception { + try { + // 加载数据库驱动类 + Class.forName("com.mysql.cj.jdbc.Driver"); + +// 获取数据库连接 + String url = "jdbc:mysql://localhost:3306/student?serverTimezone=UTC"; + String username = "root"; + String password = "123456"; + Connection conn = DriverManager.getConnection(url, username, password); + +// 创建SQL语句 + String sql = "SELECT * FROM teacher_info WHERE id = ? AND teacher_age = ?"; + +// 创建PreparedStatement对象 + PreparedStatement pstmt = conn.prepareStatement(sql); + +// 设置参数值 + pstmt.setInt(1, 1); + pstmt.setInt(2, 35); + + +// 执行SQL语句并获取结果集 + ResultSet rs = pstmt.executeQuery(); + +// 遍历结果集并处理数据 + while (rs.next()) { + int id = rs.getInt("id"); + String name = rs.getString("teacher_name"); + int age = rs.getInt("teacher_age"); + System.out.println("id: " + id + ", name: " + name + ", age: " + age); + } + +// 关闭连接，释放资源 + rs.close(); + pstmt.close(); + conn.close(); + } catch (Exception e) { + e.printStackTrace(); + } + } + public static void wylrz3()throws Exception{ + try { + + } catch (Exception e) { + e.printStackTrace(); + } + } +}