We can probably assume the pattern will always start with a / (since that's part of the path) and end with some sort of .ext: 
my $line = 'root 30145 1 0 Jan30 ? 00:09:01 /root/java/app/java_app_1R
+ule_java_app_2Rule.java --javaproc';

if ($line =~ m|/([^/]*?)\.[a-z0-9]+|) {
    print "$1\n";
}

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In reply to Re: extract file name from path by TJPride
in thread extract file name from path by Anonymous Monk

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