Java Database Connectivity (JDBC)

Dear Pro.:
i tried to test my driver version, and the error message is:

Exception in thread "main" java.sql.SQLException: Invalid Oracle URL specified
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:168)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:210)
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:273)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:182)
at java.sql.DriverManager.getConnection(DriverManager.java:512)
at java.sql.DriverManager.getConnection(DriverManager.java:171)
at Test.main(Test.java:6)

below is my tnsnames.ora data:

# TNSNAMES.ORA Network Configuration File: D:\oracle\ora81\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

WENDB =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = wenkai)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = WENDB)
)
)

INST1_HTTP =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = wenkai)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = SHARED)
(SERVICE_NAME = WENDB)
(PRESENTATION = http://admin)
)
)

EXTPROC_CONNECTION_DATA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC0))
)
(CONNECT_DATA =
(SID = PLSExtProc)
(PRESENTATION = RO)
)
)

i used thin driver, my database is wendb, user is wen, pwd is wen
what would be the correct URL:
Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@?:?:?","wen","wen");

thank you...