使用SQL Developer无法连接数据库（未读取tnsnames.ora配置）

• 我已经在Linux Mint系统上安装好了Oracle 11g和SQL Developer
• 我在.bashrc文件里配置了ORACLE_PATH以及相关环境变量，现在可以通过sqlplus正常连接数据库

下面是我的tnsnames.ora配置片段：

XE = 
  (DESCRIPTION = 
    (ADDRESS = (PROTOCOL = TCP)(HOST = hostname)(PORT = 1521)) 
    (CONNECT_DATA = 
      (SERVER = DEDICATED) 
      (SERVICE_NAME = XE) 
    ) 
  ) 
EXTPROC_CONNECTION_DATA = 
  (DESCRIPTION = 
    (ADDRESS_LIST = 
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC_FOR_XE)) 
    ) 
    (CONNECT_DATA = 
      (SID = PLSExtProc) 
      (PRESENTATION = ...
    ) 
  )

内容的提问来源于stack exchange，提问作者inityk