Example Analysis of the underlying Encapsulation of java connection mysql
Editor to share with you the java connection mysql underlying encapsulation example analysis, I believe that most people do not know much about it, so share this article for your reference, I hope you will learn a lot after reading this article, let's go to know it!
Connect to the database
Package com.dao.db;import java.sql.Connection;import java.sql.SQLException;/** * database connection layer MYSQL * @ author Administrator * * / public class DBConnection {/ * connect to the database * @ return * / public static Connection getDBConnection () {/ / 1. Registered driver try {Class.forName ("com.mysql.jdbc.Driver");} catch (ClassNotFoundException e) {/ / TODO Auto-generated catch block e.printStackTrace ();} / / get the connection to the database try {Connection conn = java.sql.DriverManager.getConnection ("jdbc:mysql://localhost/mysql?useUnicode=true&characterEncoding=utf-8", "root", "root"); return conn;} catch (SQLException E1) {e1.printStackTrace () } return null;}}
Data layer encapsulation
Package com.dao.db;import java.sql.Connection;import java.sql.PreparedStatement;import java.sql.ResultSet;import java.sql.ResultSetMetaData;import java.sql.SQLException;import java.sql.Types;import java.util.ArrayList;import java.util.HashMap;/** * MYSQL database underlying encapsulation * @ author Administrator * * / public class DBManager {private PreparedStatement pstmt; private Connection conn; private ResultSet rs / * Open database * / public DBManager () {conn = DBConnection.getDBConnection ();} / * perform modify and add operation * @ param coulmn * @ param type * @ param sql * @ return * @ throws SQLException * / public boolean updateOrAdd (String [] coulmn, int [] type, String sql) throws SQLException {if (! setPstmtParam (coulmn, type, sql) return false; boolean flag = pstmt.executeUpdate () > 0?true:false CloseDB (); return flag;} / * get query result set * @ param coulmn * @ param type * @ param sql * @ throws SQLException * / public DataTable getResultData (String [] coulmn, int [] type, String sql) throws SQLException {DataTable dt = new DataTable (); ArrayListlist = new ArrayList (); if (! setPstmtParam (coulmn, type, sql) return null; rs = pstmt.executeQuery (); ResultSetMetaData rsmd = rs.getMetaData () / / take the column name of the database int numberOfColumns = rsmd.getColumnCount (); while (rs.next ()) {HashMap rsTree = new HashMap (); for (int rud1terr)
