I ran into some code that has the following:
String foo = getvalue("foo");
if (StringUtils.isBlank(foo))
doStuff();
else
doOtherStuff();
This appears to be functionally equivalent to the following:
String foo = getvalue("foo");
if (foo.isEmpty())
doStuff();
else
doOtherStuff();
Is a difference between the two (org.apache.commons.lang3.StringUtils.isBlank
and java.lang.String.isEmpty
)?
StringUtils.isBlank()
checks that each character of the string is a whitespace character (or that the string is empty or that it's null). This is totally different than just checking if the string is empty.
From the linked documentation:
Checks if a String is whitespace, empty ("") or null.
StringUtils.isBlank(null) = true StringUtils.isBlank("") = true StringUtils.isBlank(" ") = true StringUtils.isBlank("bob") = false StringUtils.isBlank(" bob ") = false
For comparison StringUtils.isEmpty:
StringUtils.isEmpty(null) = true
StringUtils.isEmpty("") = true
StringUtils.isEmpty(" ") = false
StringUtils.isEmpty("bob") = false
StringUtils.isEmpty(" bob ") = false
Warning: In java.lang.String.isBlank() and java.lang.String.isEmpty() work the same except they don't return true
for null
.
java.lang.String.isBlank()
(since Java 11)