Supplementary Characters as Surrogates

To support supplementary characters without changing the char primitive data type and causing incompatibility with previous Java programs, supplementary characters are defined by a pair of code point values that are called surrogates . The first code point is from the high surrogates range of U+D800 to U+DBFF , and the second code point is from the low surrogates range of U+DC00 to U+DFFF . For example, the Deseret character LONG I, U+10400 , is defined with this pair of surrogate values: U+D801 and U+DC00 .