Importjava.sql.Connection;ImportJava.sql.DriverManager;Importjava.sql.PreparedStatement;ImportJava.sql.ResultSet;Importjava.sql.SQLException;Importjava.util.ArrayList;ImportJava.util.HashMap;Importjava.util.List; Public classConnectiontest { Public StaticConnection getconnection () {//Defining ConnectionsConnection Connection =NULL; Try { //Load DriverClass.forName ("Com.mysql.jdbc.Driver"); Connection= Drivermanager.getconnection ("Jdbc:mysql://localhost:3306/test", "root", "123456"); } Catch(Exception e) {e.printstacktrace (); } returnconnection; } Public StaticListGetmysqldata () {Connection Connection=NULL; //pre-Execute loadPreparedStatement PreparedStatement =NULL; //result setResultSet ResultSet =NULL; Connection=getconnection (); String sqlString= "SELECT * from User"; ListNewArraylist(); Try{PreparedStatement=connection.preparestatement (sqlString); ResultSet=Preparedstatement.executequery (); HashMap<string, object> map =NULL; while(Resultset.next ()) {map=NewHashmap<string, object>(); Map.put ("Name", Resultset.getstring ("user_name")); List.add (map); } } Catch(SQLException e) {e.printstacktrace (); } finally { Try { if(ResultSet! =NULL) {resultset.close (); } if(PreparedStatement! =NULL) {preparedstatement.close (); } if(Connection! =NULL) {connection.close (); } } Catch(SQLException e) {e.printstacktrace (); } } returnlist; } Public Static voidMain (string[] args) {ListGetmysqldata (); for(Hashmap<string, object>map:mysqldata) {System.out.println (Map.get ("Name")); } }}
Java Connection Database Test class