Check whether a string is not null and not empty

Question

How can I check whether a string is not null and not empty?

public void doStuff(String str)
{
    if (str != null && str != \"**here I want to check          


        

Answer 1

Simply, to ignore white space as well:

if (str == null || str.trim().length() == 0) {
    // str is empty
} else {
    // str is not empty
}