Can we rely on String.isEmpty for checking null condition on a String in Java?
No, absolutely not - because if acct
is null, it won't even get to isEmpty
... it will immediately throw a NullPointerException
.
Your test should be:
if (acct != null && !acct.isEmpty())
Note the use of &&
here, rather than your ||
in the previous code; also note how in your previous code, your conditions were wrong anyway - even with &&
you would only have entered the if
body if acct
was an empty string.
Alternatively, using Guava:
if (!Strings.isNullOrEmpty(acct))
Use StringUtils.isEmpty
instead, it will also check for null.
Examples are:
StringUtils.isEmpty(null) = true
StringUtils.isEmpty("") = true
StringUtils.isEmpty(" ") = false
StringUtils.isEmpty("bob") = false
StringUtils.isEmpty(" bob ") = false
See more on official Documentation on String Utils.