dbconnection.java

来自「A brew application taking backup of the 」· Java 代码 · 共 75 行

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package DBConnection;

import Login.SessionUtil;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.http.HttpSession;
import javax.sql.DataSource;

public class DBConnection {
    Connection conn = null;
    Statement stmt = null;
    InitialContext ctx;
    DataSource ds;
    ResultSet rs;
    HttpSession session = SessionUtil.getSession();

    public Connection Mobile_Master() throws SQLException {       
            try {
                if(session.getAttribute("connection").toString().equals("")) {
                    System.out.println("Getting Connection..");
                    ctx = new InitialContext();
                    ds = (DataSource) ctx.lookup("Mobile_Master");
                    conn = ds.getConnection();
                    session.setAttribute("connection", conn);
                } else{
                    conn = (Connection) session.getAttribute("connection");
                }
            } catch (NamingException ex) {
                Logger.getLogger(DBConnection.class.getName()).log(Level.SEVERE, null, ex);
            }           
        return conn;
    }

    public void insert(String Query) throws SQLException {
        if (conn==null)
            conn = Mobile_Master();
        try {
            stmt = conn.createStatement();
            stmt.execute(Query);
        } catch (SQLException ex) {
            Logger.getLogger(DBConnection.class.getName()).log(Level.SEVERE, null, ex);
        }      
    }

    public void delete(String Query) throws SQLException {
        if (conn==null)
           conn = Mobile_Master();
        insert(Query);      
    }

    public ResultSet select(String Query) throws SQLException {
        if (conn==null)
            conn = Mobile_Master();
        try {
            stmt = conn.createStatement();
            stmt.execute(Query);
            rs = stmt.getResultSet();
        } catch (SQLException ex) {
            Logger.getLogger(DBConnection.class.getName()).log(Level.SEVERE, null, ex);
        }      
        return rs;
    }
}