Does a filter instance handle multiple requests?

A web container creates a thread to handle each request so that a servlet instance handles multiple requests at the sime time. What about a filter instance? Does a filter instance also handles
multiple requests? or it handles only one at a time

Here's a quote from the Servlet spec (2.3):
After deployment of the web application, and before a request causes the container
to access a web resource, the container must locate the list of filters that must be
applied to the web resource as described below. The container must ensure that it
has instantiated a filter of the appropriate class for each filter in the list, and called its
init(FilterConfig config) method..............
Only one instance per filter declaration in the deployment descriptor is
instantiated per Java virtual machine of the container.
So, if the servlet engine follows the spec, there should only be one instance.

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    ip6tables          0:off    1:off    2:on    3:on    4:on    5:on    6:off
    iptables           0:off    1:off    2:on    3:on    4:on    5:on    6:off
    irqbalance         0:off    1:off    2:off    3:on    4:on    5:on    6:off
    jexec              0:off    1:on    2:on    3:on    4:on    5:on    6:off
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    network            0:off    1:off    2:on    3:on    4:on    5:on    6:off
    ntpd               0:off    1:off    2:off    3:off    4:off    5:off    6:off
    ntpdate            0:off    1:off    2:off    3:off    4:off    5:off    6:off
    portreserve        0:off    1:off    2:on    3:on    4:on    5:on    6:off
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    rsyslog            0:off    1:off    2:on    3:on    4:on    5:on    6:off
    saslauthd          0:off    1:off    2:off    3:off    4:off    5:off    6:off
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    sysstat            0:off    1:on    2:on    3:on    4:on    5:on    6:off
    udev-post          0:off    1:on    2:on    3:on    4:on    5:on    6:off
    vmware-tools       0:off    1:off    2:on    3:on    4:on    5:on    6:off
    vmware-tools-thinprint    0:off    1:off    2:on    3:on    4:on    5:on    6:off
    wdaemon            0:off    1:off    2:off    3:off    4:off    5:off    6:off
    winbind            0:off    1:off    2:off    3:off    4:off    5:off    6:off
    wpa_supplicant     0:off    1:off    2:off    3:off    4:off    5:off    6:off
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