Openfire 3.9.3 failed to start on CentOS 7

1st: I installed a new CentOS 7 on VMWare as "minimal" which OS Version info is:

CentOS Linux 7 (Core)

Kernel 3.10.0-123.el7.x86_64 on an x86_64

2nd:

I install openjdk-1.7.0 with command:

yum install java-1.7.0-openjdk

which completed ok:

[root@localhost ~]# java -version

java version "1.7.0_65"

OpenJDK Runtime Environment (rhel-2.5.1.2.el7_0-x86_64 u65-b17)

OpenJDK 64-Bit Server VM (build 24.65-b04, mixed mode)

3rd:

wget openfire-3.9.3-1.i386.rpm from igniterealtime.org and install the package:

rpm -ivf openfire-3.9.3-1.i386.rpm

and the system tell me it's ok just like these:

Preparing packages...

openfire-3.9.3-1.i386

Restarting openfire (via systemctl):  [  OK  ]

But when I check the service status I found it didn't work.

[root@localhost ~]# service openfire status -l

openfire is not running

[root@localhost ~]# service openfire start

Starting openfire (via systemctl):  Job for openfire.service failed. See 'systemctl status openfire.service' and 'journalctl -xn' for details.

                                                           [FAILED]

[root@localhost ~]# systemctl status openfire -l

openfire.service - SYSV: Openfire is an XMPP server, which is a server that facilitates XML based communication, such as chat.

   Loaded: loaded (/etc/rc.d/init.d/openfire)

   Active: failed (Result: resources) since Tue 2014-08-12 07:21:16 EDT; 13s ago

  Process: 10583 ExecStart=/etc/rc.d/init.d/openfire start (code=exited, status=0/SUCCESS)

Aug 12 07:21:15 localhost.localdomain su[10593]: (to daemon) root on none

Aug 12 07:21:15 localhost.localdomain openfire[10583]: Starting openfire:

Aug 12 07:21:16 localhost.localdomain systemd[1]: Failed to read PID from file /var/run/openfire.pid: Invalid argument

Aug 12 07:21:16 localhost.localdomain systemd[1]: Failed to start SYSV: Openfire is an XMPP server, which is a server that facilitates XML based communication, such as chat..

Aug 12 07:21:16 localhost.localdomain systemd[1]: Unit openfire.service entered failed state.

I did nothing besides the commands I wrote. So what happened? Why Openfire " Failed to read PID from file /var/run/openfire.pid: Invalid argument"?

Thanks.