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copied!<p>You can use EOF actions (section 3.2.2 EOF Actions in the Ragel documentation) for checking of the expressions on the fly with Ragel. They are triggered when end of input buffer is detected in a valid state (including non-final).</p> <p>Simple example:</p> <pre><code> main := ([a-z]{2,5}'ABC'[0-9]+) @/{correct = 1;} %{correct = 1;}; </code></pre> <p>Action "@/" is for all non-final states. It includes starting state so empty string is correct for this case. Action "%" is for final state when entire input buffer matches the pattern. In the example above code for both actions are the same, but final state is often to be processed separately in practice. If it is not needed then the sample above can be simplified:</p> <pre><code> main := ([a-z]{2,5}'ABC'[0-9]+) $/{correct = 1;}; </code></pre> <p>The complete Ragel sample with C output for checking the provided pattern is below. I hope that it is not a problem to convert it to Java.</p> <pre><code> #include <stdio.h> %%{ machine checker; write data; }%% unsigned char checker( const char *str ) { /* standart Ragel variables */ const char *p = str, *pe = str + strlen( str ) - 1; //-1 to strip "\n" const char *eof = pe; int cs; unsigned char correct = 0; %%{ action final { printf("entire match"); correct = 1; } action partial { printf("partial match"); correct = 1; } main := ([a-z]{2,5}'ABC'[0-9]+) @/partial %final; write init; write exec; }%% return correct; }; #define BUFSIZE 1024 int main() { char buf[BUFSIZE]; while ( fgets( buf, sizeof(buf), stdin ) != 0 ) { printf( "%d\n", checker( buf )); } return 0; } </code></pre>

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