tm4j-developers

[Tm4j-developers] help on using value-like() predicate in tolog

[suseela s. <sus...@ya...>]

Hi
 
I like to find objects in a topic map which matches
a pattern. For example all base names that contains
"refer".  I am not sure I understood the usage.
 
Tried the following for the simple query (leaving out ? etc)
 value-like($A, "refer")
 value-like($A, "\\.*refer.*\\")
 value-like($A, "*refer*")
 
All three gave the parsing error "Error instantiating predicate class".
Can some body please tell me the correct usage.
 
thanks
suseela



		
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Re: [Tm4j-developers] help on using value-like() predicate in tolog

[Kal A. <ka...@te...>]

Hi Suseela,

The format of the predicate is correct (i.e. a variable or object 
reference as the first parameter and a search string as the second 
parameter). The text searching for value-like is done using the TM4J 
Lucene integration so the search string should use Lucene's query syntax 
which is documented at 
http://jakarta.apache.org/lucene/docs/queryparsersyntax.html

Also you should note that the tolog engine does not instantiate the 
full-text index automatically so you need to do that in your code before 
running any tolog queries which use value-like. See the example code in 
examples/fulltext/FullTextSearch.java.

If you have a full stack trace for the error (or if you can change your 
code to produce one) that would be helpful in tracing the cause of this 
problem.

Cheers,

Kal

suseela sarasamma wrote:

> Hi
>
> I like to find objects in a topic map which matches
> a pattern. For example all base names that contains
> "refer".  I am not sure I understood the usage.
>
> Tried the following for the simple query (leaving out ? etc)
> value-like($A, "refer")
> value-like($A, "\\.*refer.*\\")
> value-like($A, "*refer*")
>
> All three gave the parsing error "Error instantiating predicate class".
> Can some body please tell me the correct usage.
>
> thanks
> suseela
>
> ------------------------------------------------------------------------
> Start your day with Yahoo! - make it your home page 
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