A Java method that tests if a String is null or blank

Problem: You’re working on a Java application, and you’re repeatedly performing a test to determine whether a String (or many strings) are either blank or null.

Solution

Create a simple Java method to perform this test for you. The following Java method returns true if a String is blank or null, otherwise it returns false:

private static boolean isNullOrBlank(String s)
{
  return (s==null || s.trim().equals(""));
}

Performing this test is so common in Java applications that I include this as a static method in one of the standard “utility” jar files that I carry with me from project to project. It makes it much easier to write code like this:

if (StringUtils.isNullOrBlank(myString))
{
  // do something important here
}

On a recent project I was working on where I used JSF to create a web user interface for Nagios I probably used this test 100 times or more.