This article aims to compare the StringUtils.isBlank() and String.isEmpty() methods in Java.

StringUtils.isBlank() is a method that checks if a string is whitespace, empty, or null, returning true for all these cases and trimming the char sequences before checking.

In contrast, String.isEmpty() only checks if a string is empty or null, returning true for these cases but false if the string contains only whitespace.

With the introduction of Java 11, the isBlank() method was introduced, which shares similarities with StringUtils.isBlank() by checking for whitespace, empty, or null strings. However, it lacks the null check that StringUtils.isBlank() has.

Additionally, StringUtils.isEmpty() is similar to String.isEmpty() as they both only check for empty or null strings. StringUtils.isEmpty() returns true for null strings, while String.isEmpty() returns false for whitespace strings.

Understanding the distinctions between null and empty strings, as well as the handling of whitespace characters, is crucial.

This article will provide an objective analysis of the differences and comparisons between these methods.

StringUtils.isBlank() Explanation

StringUtils.isBlank() is a method that checks if a string is whitespace, empty, or null by trimming the char sequences and returning true for null, empty string, and whitespace.

It is a part of the Apache Commons Lang library and is commonly used in Java programming.

The method isBlank(null) raises a NullPointerException.

This method is also available in Java 11 as isBlank(). The main difference between StringUtils.isBlank() and StringUtils.isEmpty() is that isBlank() also checks for whitespace characters, whereas isEmpty() only checks for empty or null strings.

It is important to note that Java 11’s isBlank() method is not equivalent to StringUtils.isBlank() as it lacks the null check.

Overall, StringUtils.isBlank() is a useful method for checking the emptiness or nullity of a string.

StringUtils.isEmpty() Explanation

The method StringUtils.isEmpty() checks whether a string is either null or empty. It returns true if the string is null or has a length of 0.

However, unlike StringUtils.isBlank(), it does not consider whitespace characters as empty. Therefore, if the string contains only whitespace characters, StringUtils.isEmpty() will return false.

This method is useful when we want to determine if a string variable has been assigned a value or not. It can help avoid potential NullPointerException errors when trying to manipulate an empty string.

It is important to note that StringUtils.isEmpty() is not available in Java 8 by default, but it can be accessed through the third-party library org.apache.commons.lang3.StringUtils.

Differences and Comparisons

One key distinction between the methods is that StringUtils.isEmpty() does not consider whitespace characters as empty, while StringUtils.isBlank() includes whitespace characters in its definition of empty.

This means that if a string contains only whitespace characters, StringUtils.isEmpty() will return false, while StringUtils.isBlank() will return true.

Additionally, StringUtils.isEmpty() returns true for null and empty strings, while StringUtils.isBlank() also returns true for null strings.

It is important to note that the behavior of these methods may vary depending on the version of Java being used.

In Java 11, the isBlank() method was introduced, which is equivalent to StringUtils.isBlank() but does not include a null check.

Therefore, it is important to use the appropriate method based on the desired behavior and Java version.