写一个java连接mysql的例子，并实现判断是否连接成功，对数据库增删改查，给出maven依赖配置，代码越详细越好

好的，下面是一个简单的Java连接MySQL的例子，包括判断连接是否成功和增删改查操作：

1. Maven依赖配置：

<dependencies>
   <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>8.0.26</version>
   </dependency>
</dependencies>

2. 连接MySQL数据库并判断是否连接成功：

import java.sql.*;

public class MySQLDemo {

   public static void main(String[] args) {
      Connection conn = null;
      try {
         // 加载驱动
         Class.forName("com.mysql.cj.jdbc.Driver");

         // 建立连接
         String url = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC";
         String username = "root";
         String password = "123456";
         conn = DriverManager.getConnection(url, username, password);

         // 判断是否连接成功
         if (conn != null) {
            System.out.println("连接成功！");
         } else {
            System.out.println("连接失败！");
         }
      } catch (ClassNotFoundException e) {
         e.printStackTrace();
      } catch (SQLException e) {
         e.printStackTrace();
      } finally {
         try {
            if (conn != null) {
               conn.close();
            }
         } catch (SQLException e) {
            e.printStackTrace();
         }
      }
   }
}

3. 对数据库进行增删改查操作：

import java.sql.*;

public class MySQLDemo {

   public static void main(String[] args) {
      Connection conn = null;
      PreparedStatement ps = null;
      ResultSet rs = null;
      try {
         // 加载驱动
         Class.forName("com.mysql.cj.jdbc.Driver");

         // 建立连接
         String url = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC";
         String username = "root";
         String password = "123456";
         conn = DriverManager.getConnection(url, username, password);

         // 插入数据
         String sql = "INSERT INTO user(name, age, sex) VALUES (?, ?, ?)";
         ps = conn.prepareStatement(sql);
         ps.setString(1, "张三");
         ps.setInt(2, 18);
         ps.setString(3, "男");
         int result = ps.executeUpdate();
         if (result > 0) {
            System.out.println("插入成功！");
         } else {
            System.out.println("插入失败！");
         }

         // 更新数据
         sql = "UPDATE user SET age = ? WHERE name = ?";
         ps = conn.prepareStatement(sql);
         ps.setInt(1, 20);
         ps.setString(2, "张三");
         result = ps.executeUpdate();
         if (result > 0) {
            System.out.println("更新成功！");
         } else {
            System.out.println("更新失败！");
         }

         // 查询数据
         sql = "SELECT * FROM user WHERE age > ?";
         ps = conn.prepareStatement(sql);
         ps.setInt(1, 18);
         rs = ps.executeQuery();
         while (rs.next()) {
            String name = rs.getString("name");
            int age = rs.getInt("age");
            String sex = rs.getString("sex");
            System.out.println("姓名：" + name + "，年龄：" + age + "，性别：" + sex);
         }

         // 删除数据
         sql = "DELETE FROM user WHERE name = ?";
         ps = conn.prepareStatement(sql);
         ps.setString(1, "张三");
         result = ps.executeUpdate();
         if (result > 0) {
            System.out.println("删除成功！");
         } else {
            System.out.println("删除失败！");
         }
      } catch (ClassNotFoundException e) {
         e.printStackTrace();
      } catch (SQLException e) {
         e.printStackTrace();
      } finally {
         try {
            if (rs != null) {
               rs.close();
            }
            if (ps != null) {
               ps.close();
            }
            if (conn != null) {
               conn.close();
            }
         } catch (SQLException e) {
            e.printStackTrace();
         }
      }
   }
}

以上是一个简单的Java连接MySQL的例子，代码中注释有详细的说明，希望能够帮助你！