连接oracle 10g数据库问题

Question

在本机不安装客户端的情况下，连接远程的oracle 10g数据库时出现如下异常：
Exception in thread "main" java.sql.SQLException: Io 异常: The Network Adapter could not establish the connection
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:179)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:333)
at oracle.jdbc.driver.OracleConnection.<init>(OracleConnection.java:404)
at oracle.jdbc.driver.OracleDriver.getConnectionInstance(OracleDriver.java:468)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:314)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at hhoracle.main(hhoracle.java:32)代码如下：
import java.sql.SQLException;
import com.sun.corba.se.pept.transport.Connection;public class hhoracle {     /**
     * @param args
     * @throws SQLException 
     */
    public static void main(String[] args) throws SQLException {
          Connection conn = null;
                 try {
      
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
System.out.println("======1=====");
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();

}
            System.out.println("======1=====");  
       
                            conn = java.sql.DriverManager.getConnection(
                "jdbc:oracle:thin:@远程oracle 10g数据库的IP地址:1521:database","user","password");
                System.out.println("======2=====");
        java.sql.Statement stmt = conn.createStatement();
               java.sql.ResultSet rs = stmt.executeQuery("select * from sys.t_info");
                while(rs.next()) {
            System.out.println(rs.getString(1));
            System.out.println(rs.getString(2));
            System.out.println();
        }
                rs.close();
        stmt.close();
        conn.close();     } }