Java 13 Text Blocks

Summary:

• Text blocks start and end with triple double quotes (""").
• They can span multiple lines, allowing you to include newlines and other white spaces directly in the string content.
• Within a text block, the format of the string is largely preserved as written in the source code, reducing the need for escape sequences.
• Indentation management: Automatic indentation is based on the position of the closing delimiter, with incidental white space removed.
• Supports string formatting and expressions with the String.format() method or formatted string literals.

Examples:

1. Basic Example:

   String textBlock = """
                      Hello,
                      World!
                      """;
   

   This creates a string containing "Hello," followed by a newline, then "World!" and another newline.

2. Including escape sequences:

   Although less common, you can still use escape sequences in text blocks if needed, such as \" for a double-quote or \\ for a backslash.

   String json = """
                 {
                     "name": "John",
                     "age": 30
                 }
                 """;
   

3. Comparing to traditional strings:

   Before Java 13, a similar multi-line string would look like this:

   String traditionalString = "Hello,\n" +
                              "World!\n";
   

   The text block version is more readable and easier to maintain.

4. Indentation and white spaces:

   Text blocks automatically remove incidental white space based on the position of the closing delimiter:

   String message = """
                    Dear Friend,
                      Thank you for your support.
                    Regards,
                    John
                    """;
   

   Here, the string retains the intended indentation levels inside the text block.

5. Formatting and expressions:

   Text blocks can be used with String.format() or formatted string literals for dynamic content:

   String name = "John";
   int age = 30;
   String userInfo = """
                     Name: %s
                     Age: %d
                     """.formatted(name, age);
   

   This incorporates variable values into the text block.

These examples demonstrate how Java text blocks simplify working with multi-line string literals, making code easier to write and maintain.

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