oracle数据库链接问题?报错

我改的一个基于struts 2的信息管理系统在连接oracle数据库时出现问题，系统原来用的是SQLserver数据库。我修改了一些链接数据库的类。原来链接SQLserver的链接代码和我改的链接代码都贴上，希望高手能帮助解决。

报错：java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC]Error establishing socket.

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class ConnectionDatabase {

	// 加载驱动
	private final String DBDRIVER = "com.microsoft.jdbc.sqlserver.SQLServerDriver";

	// 连接数据库的路径
	private final String DBURL = "jdbc:microsoft:sqlserver://localhost:1433;databasename=hospitaldb";

	// 连接数据库的用户名
	private final String DBUSER = "sa";

	// 连接数据库的密码
	private final String DBPASSWORD = "sa";

	// 连接数据库的对象
	public Connection conn = null;

	private PreparedStatement ps = null;
	private ResultSet rs = null;

	public ConnectionDatabase() {

		try {
			Class.forName(DBDRIVER);

			this.conn = DriverManager.getConnection(DBURL, DBUSER, DBPASSWORD);

		} catch (Exception e) {

			e.printStackTrace();
			System.out.println("数据库连接失败" + this.conn + DBURL + DBUSER
					+ DBPASSWORD);
		}
	}

	// 取得数据库连接
	public Connection getConnection() {

		return this.conn;
	}

	// 关闭数数据库连接
	public void close() {

		try {

			this.conn.close();

		} catch (Exception e) {
		}
	}

	// 实现查询
	public ResultSet select(String sql) {
		try {

			ps = getConnection().prepareStatement(sql);
			rs = ps.executeQuery();
			return rs;
		} catch (SQLException se) {
			se.printStackTrace();
			return null;
		}

	}

	// 实现增删改
	public boolean noselect(String sql) {
		try {
			ps = getConnection().prepareStatement(sql);
			int i = 0;
			i = ps.executeUpdate();
			return i >= 1;
		} catch (SQLException se) {
			se.printStackTrace();
			return false;
		} finally {
		}
	}

	// 将于数据库相连的各个对象顺序关闭
	public void closeAll(ResultSet r, Statement s, Connection c) {

		try {
			if (r != null)
				r.close();
			if (s != null)
				s.close();
			if (s != null)
				s.close();
			if (c != null)
				c.close();
		} catch (SQLException e) {

			e.printStackTrace();
		}

	}

}

import java.sql.*; 
public class ConnectionDatabase { 
//dbUrl数据库连接串信息，其中“1521”为端口，“ora9”为sid 
String dbUrl = "jdbc:oracle:thin:@211.87.20.15:1521:ora9"; 
//theUser为数据库用户名 
String theUser = "admin"; 
//thePw为数据库密码 
String thePw = "1234"; 
//几个数据库变量 
Connection conn = null; 
Statement ps; 
ResultSet rs = null; 
//初始化连接 
public ConnectionDatabase() { 
try { 
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance(); 
//与url指定的数据源建立连接 
conn = DriverManager.getConnection(dbUrl, theUser, thePw); 
//采用Statement进行查询 
ps = conn.createStatement(); 
} catch (Exception e) { 
e.printStackTrace(); 
} 
} 
//执行查询 
public ResultSet executeQuery(String sql) { 
rs = null; 
try { 
rs = ps.executeQuery(sql); 
} catch (SQLException e) { 
e.printStackTrace(); 
} 
return rs; 
} 
public void close() { 
try { 
ps.close(); 
conn.close(); 
} catch (Exception e) { 
e.printStackTrace(); 
} 
} 
public static void main(String[] args) { 
ResultSet newrs; 
ConnectionDatabase newjdbc = new ConnectionDatabase(); 
newrs = newjdbc.executeQuery("select * from eventtype"); 
try { 
while (newrs.next()) { 
System.out.print(newrs.getString("event_type")); 
System.out.println(":"+newrs.getString("content")); 
} 
} catch (Exception e) { 
e.printStackTrace(); 
} 
newjdbc.close(); 
} 
}