ChatGPT with GPT-4 seems to get this right: In Java, strings are internally represented by an instance of the `String` class, which is an immutable class that

ChatGPT with GPT-4 seems to get this right: In Java, strings are internally represented by an instance of the `String` class, which is an immutable class that means once created, a `String` object cannot be changed. The `String` class stores character data as an array of `char` data type. Prior to Java 9, this array was encoded as UTF-16. This means that each character in the string is typically stored in 2 bytes (16 bits), which can represent a range of Unicode characters. Starting with Java 9, the `String` class uses a `byte` array, plus an encoding-flag field, to store string data. This change was part of the "compact strings" optimization, which is aimed at reducing the memory footprint of `String` objects. The flag tells the JVM whether the string is encoded as UTF-16 or Latin-1 (ISO-8859-1), depending on the string's content. If a string can be represented using Latin-1, it will be, because Latin-1 uses only 1 byte per character, which can save memory compared to the 2-byte UTF-16 encoding. It's worth noting that these implementation details are internal to the `String` class and aren't usually something you need to worry about when writing Java code. They could also potentially change in future versions of Java.