import java.sql.*; public class testMDBagain { // JDBC driver name and database URL static final String JDBC_DRIVER = "org.mariadb.jdbc.Driver"; static final String DB_URL = "jdbc:mariadb://localhost:3306/cs4010"; // Database credentials static final String USER = "cs4010"; static final String PASS = "cs4010"; public static void main(String[] args) { Connection conn = null; Statement stmt = null; try { //STEP 2: Register JDBC driver Class.forName(JDBC_DRIVER); //STEP 3: Open a connection System.out.println("Connecting to database..."); conn = DriverManager.getConnection(DB_URL,USER,PASS); //STEP 4: Execute a query System.out.println("Creating statement..."); stmt = conn.createStatement(); int the_query=Integer.parseInt(args[0]); String[] sql=new String[3]; sql[0] = "SELECT name, year, test FROM student;"; sql[1]="SELECT a.name, a.year, a.test, b.sport from student a,athlete b where b.this_student=a.student_id;"; sql[2]="SELECT name, year, test FROM student where name=\""; String this_query=""; this_query=sql[the_query]; if (the_query==2) { this_query=this_query+args[1]+"\";"; } System.out.println(this_query+"\n"); ResultSet rs = stmt.executeQuery(this_query); //STEP 5: Extract data from result set while (rs.next()) { //Retrieve by column name String the_name = rs.getString("name"); String the_year = rs.getString("year"); int the_grade = rs.getInt("test"); String the_sport=""; if (the_query==1) the_sport = rs.getString("sport"); //Display values if(the_query==1) System.out.println("Name: " + the_name + " Year: "+the_year+" Grade: "+the_grade+" Sport: "+the_sport); else System.out.println("Name: " + the_name + " Year: "+the_year+" Grade: "+the_grade); } //STEP 6: Clean-up environment rs.close(); stmt.close(); conn.close(); } catch (SQLException se) { //Handle errors for JDBC se.printStackTrace(); } catch (Exception e) { //Handle errors for Class.forName e.printStackTrace(); } finally { //finally block used to close resources try { if (stmt!=null) stmt.close(); } catch (SQLException se2) { }// nothing we can do try { if (conn!=null) conn.close(); } catch (SQLException se) { se.printStackTrace(); }//end finally try }//end try System.out.println("Goodbye!"); }//end main }//end FirstExample