dbmanager.java

针对java程序编写的关于dtree的程序代码

package com.xaccp.dbmanger;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import javax.sql.DataSource;

public class DBManager {

    private static DataSource dataSource = null;
    private static Connection conn = null;

    /**
     * 防止用户实例化
     */
    private DBManager() {}

    /**
     * 接收数据源
     * @param ds DataSource
     */
    public static void setDataSource(DataSource ds) {
        if (ds!=null) {
            dataSource = ds;
        }
    }

    public static Connection createConnection() {
        if (dataSource==null) {
            try {
				Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
				conn = DriverManager.getConnection("jdbc:microsoft:sqlserver://localhost:1433;databaseName=demp","sa","");
				return conn;
			} catch (Exception e) {				
				e.printStackTrace();
				return null;
			}
        }
        else {
            try {
                return dataSource.getConnection();
            } catch (SQLException ex) {
                ex.printStackTrace();
                return null;
            }
        }
    }
}