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import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; public class DBDemo { private Connection connection; private Statement statement; public DBDemo() { try { connection = DriverManager.getConnection("jdbc:sqlite:Test.db"); statement = connection.createStatement(); statement.setQueryTimeout(30); // set timeout to 30 sec. } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void showInfo() { ResultSet rs; //System.out.println("show all info in DB"); try { rs = statement.executeQuery("select * from stuinfo"); int i=0; while(rs.next()) { // read the result set System.out.print("stuID = " + rs.getInt("stuID")); System.out.print(". name = " + rs.getString("name")); System.out.println(". cardID = " + rs.getString("cardID")); i=i+1; } if(i==0) { System.out.println("DB is empty."); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void deleteInfo() { try { statement.executeUpdate("delete from stuinfo"); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void insertInfo() { try { statement.executeUpdate("insert into stuinfo values(1150299888, 'root','0C67F171')"); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public void changeInfo() { try { statement.executeUpdate("update stuinfo set cardID='11223344' where stuID=1150299888"); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void main(String[] args) { // TODO Auto-generated method stub DBDemo d=new DBDemo(); System.out.println("original info"); d.showInfo(); d.deleteInfo(); System.out.println("after deletion"); d.showInfo(); d.insertInfo(); System.out.println("after insertion"); d.showInfo(); d.changeInfo(); System.out.println("after update"); d.showInfo(); } }