JDK Tutorials - Herong's Tutorial Examples - Version 6.02, by Dr. Herong Yang
What Is Character Encoding?
This section provides introductions on what is a character encoding - A map scheme between code points of a code character set and sequences of bytes.
Character Encoding: A map scheme between code points of a code character set and sequences of bytes.
Coded Character Set: A character set in which each character has an assigned a code point (i.e. an integral number).
Code Point: An integral number assigned to a character in a coded character set.
Unicode: A coded character set that contains all characters used in the written languages of the world and special symbols.
As of 1.8, JDK supports Unicode 6.2 with the following primitive types and classes:
char - A primitive type with 16-bit storage size, which was perfectly designed to store the code point value of a single Basic Multilingual Plane (BMP) Unicode character ranging from U+0000 to U+FFFF,
int - A primitive type with 32-bit storage size, which is borrowed to handle the code point value of any Unicode character ranging from U+0000 to U+10FFFF.
java.lang.Character - A built-in class that wraps a value of the primitive type char in an object. The Character class was perfectly designed to represent a single BMP character as an object. The Character class also provides some useful static methods for managing individual BMP characters.
java.lang.String - A built-in class that wraps an array of primitive type char (char) in an object. A Unicode character string can be stored in a String object using the UTF-16BE encoding, where a BMP character (code value in the range of U+0000 to U+FFFF) is represented by a single char element and a supplement supplementary character (code value in the range of U+10000 to U+10FFFF) is represented by two char elements called surrogate char pair.
Last update: 2014.
Table of Contents