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src/main/java/com/example/Jdbc.java

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+package com.example;
+
+import java.sql.*;
+
+public class Jdbc {
+    private Connection conn;
+    private Statement stmt;
+    private ResultSet rs;
+
+    Jdbc(){
+        try {
+            Class.forName("com.mysql.cj.jdbc.Driver");
+            String password = "root";
+            String username = "root";
+            conn= DriverManager.getConnection("jdbc:mysql://localhost:3306/su?useSSL=false&serverTimezone=UTC", username, password);
+            stmt=conn.createStatement();
+        } catch (ClassNotFoundException | SQLException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public ResultSet query(String sql) throws SQLException {
+        rs=stmt.executeQuery(sql);
+        return rs;
+    }
+
+    public void update(String sql) throws SQLException {
+        stmt.executeUpdate(sql);
+    }
+    public void close() throws SQLException {
+        if(rs!=null){
+            rs.close();
+        }
+        if(stmt!=null){
+            stmt.close();
+        }
+        if(conn!=null){
+            conn.close();
+        }
+    }
+}