Granny's Programming Pearls
"inside of every large program is a small program struggling to get out"
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to use == or equals on getString ?

 
Chris Davies
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i'm using the following code within a page


<c:resultSet id="rs" name="bean" type="java.sql.ResultSet"><webtop:column id="column" name="bean" fieldname="TERM_COLUMN">

<c:ifThen
condition='<%= !rs.getString()
%>'>

in terms of using the rs.getString method do i have to use

== null or

rs.getString().equals null


if i want to test it prior to displaying it on the jsp page ?

also would i have to use the <c:else> tag after this then would the ocde know that if it didn't fulfill the ifthen condition then it shouldn't process ?

cheers

chris
 
Dirk Schreckmann
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Use == to test for a null reference, and the equals method to test a non-null reference for its value. Note that if you were to invoke any method, including the equals method, on a null reference, you'll get a NullPointerException.

For questions specific to JSPs, mosey on over to the JSP forum.
 
Jeroen Wenting
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rs.getString() returns a String.
Unless you want to check for null on a String you should always use equals.

Remember that the <%= ... %gt; block can only output Strings to the JSP output stream, so the result of your statement must be a String or be capable of being converted into a meaningful String using toString().
 
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