Advanced String Concepts

• delimiter: The separator you want between each element.
• elements: The strings or elements you wish to concatenate.

Example

In this example, the join() method joins the elements of the array with a space " " delimiter. This method can be very useful when you need to concatenate elements from a collection, avoiding manual loops or StringBuilder.

isBlank() vs isEmpty()

Java provides two methods—isBlank() and isEmpty()—to check whether a string is empty. Although they sound similar, they have distinct differences.

isEmpty()

The isEmpty() method checks if the string has zero length. If the string is empty (i.e., its length is 0), it returns true; otherwise, it returns false.

• isEmpty() only returns true for an empty string (""), but not for a string with only whitespace.
• Use isEmpty() when you need to check if a string contains any characters at all.

Syntax

Example

isBlank()

The isBlank() method, introduced in Java 11, checks if a string is empty or contains only whitespace characters (spaces, tabs, or newlines).

• It returns true if the string is empty or contains only whitespace. isBlank() returns true for both empty strings and strings that only contain whitespace.
• Use isBlank() when you want to check if the string is either empty or contains only whitespace characters.

Syntax

Example

Multiline Strings with Text Blocks (Java 13+)

Java 13 introduced Text Blocks, which allow you to define multiline strings more easily and with improved readability. Text Blocks are enclosed in triple quotes (""") and allow you to write strings across multiple lines without needing to concatenate individual lines manually or escape newline characters.

Syntax