test.java

来自「JSP+JavaBean+Servlet 办公自动化管理系统由前台管理和后台管」· Java 代码 · 共 40 行

package test;

import java.sql.Connection;
import java.sql.SQLException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

public class Test {
	private static DataSource dsCache = null;

	public Connection aMethodForGetConnectio() throws NamingException, SQLException {
		if (dsCache == null) {
			synchronized (this) {
				if (dsCache == null) {
					Context ct = new InitialContext();
					dsCache = (DataSource) ct.lookup("jdbc/oa");
				}
			}
		}
		Connection conn = dsCache.getConnection();
		return conn;
	}
	public static void main(String[] args){
		Test t = new Test();
		try {
			Connection con = t.aMethodForGetConnectio();
			System.out.println("dfsda");
		} catch (NamingException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}