What is the correct way to check if a String is empty or null in Java, and how can I avoid potential errors?

General Discussions
, ,
4

Definitely love what you both said! One thing I’ve learned when dealing with messy data (like HTML or form inputs) is that sometimes a string might contain spaces or tabs that you don’t see but still consider it non-empty. That’s when trim() comes in handy.

if (string == null || string.trim().isEmpty()) {
    Log.d("iftrue", "String is null, empty, or just whitespace");
} else {
    Log.d("iffalse", "String has visible characters");
}

Here, .trim() removes leading and trailing whitespace, so it ensures you’re only checking for visible content. This is especially useful when parsing HTML or messy input data, which often contains invisible characters. So, if you need to java check if string is empty or just full of whitespace, this method adds a nice layer of reliability.