[JavaEE] JDBC Quick Start and javaeejdbc Quick Start

[JavaEE] JDBC Quick Start and javaeejdbc Quick Start

JDBC: Java Data Base Connectivity java Database Connection

 

1. Two JDBC packages: Interfaces

Java. SQL javax. SQL

2. JDBC database implementation

 

Add mysql-connector-java-5.0.8-bin.jar under tomcat directory this database driver package

 

Package com. tsh. web; import java. io. IOException; import java. SQL. connection; import java. SQL. driverManager; import java. SQL. resultSet; import java. SQL. statement; import javax. servlet. servletException; import javax. servlet. http. httpServlet; import javax. servlet. http. httpServletRequest; import javax. servlet. http. httpServletResponse;/***/public class DbServlet extends HttpServlet {private static final long serialVersionUID = 1L;/***/public DbServlet () {super (); // TODO Auto-generated constructor stub}/***/protected void doGet (HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {try {// register the database driver // DriverManager. registerDriver (new Driver (); // Class Using Reflection. forName ("com. mysql. jdbc. driver "); // get the database connection. When importing a package, note that you must import java. in SQL, Connection conn = DriverManager for interface programming. getConnection ("jdbc: mysql: // localhost: 3306/java", "root", "root"); // get the transmitter object Statement = conn. createStatement (); // obtain the result set object ResultSet resultSet=statement.exe cuteQuery ("select * from user"); // traverse while (resultSet. next () {String username = resultSet. getString ("username"); response. getWriter (). write (username) ;}} catch (Exception e) {e. printStackTrace () ;}/ ***/protected void doPost (HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {}}