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Evaluating EL

 
Alec Lee
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In p393 of HFS, there is such an exercise

evaluates:

${num == integer-1}

where in another servlet dispatching to this jsp:
...
integer i= new Integer(3);
request.setAttribute("integer",i);
String num="2";
request.setAttribute("num",num);
...

My question is what are the exact rules for evaluating object type expression in EL? Are they all toString'ed? In above e.x., 'integer' should be evaluated to Integer type while 'num' is evaluated to String type. I guess the 2 must be converted to some common type before being compared. But what are the exact rules for this? HFS does not explain this in detail. Where could I find more information?

Thx
 
Mat Williams
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Hi,

This is not an exact answer but I suggest that you download the jsp 2.0 specification form here and read Part I, Expression Langugage, particularly page 1-78. It will help you out in this regard.

HTH Mat
 
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