Why does the Java char primitive take up 2 bytes of memory?

java unicode utf-16 widechar
realnumber picture realnumber · Oct 18, 2010 · Viewed 38.6k times · Source

Is there any reason why Java char primitive data type is 2 bytes unlike C which is 1 byte?

Thanks

Answer

Matthew Flaschen picture Matthew Flaschen · Oct 18, 2010

When Java was originally designed, it was anticipated that any Unicode character would fit in 2 bytes (16 bits), so char and Character were designed accordingly. In fact, a Unicode character can now require up to 4 bytes. Thus, UTF-16, the internal Java encoding, requires supplementary characters use 2 code units. Characters in the Basic Multilingual Plane (the most common ones) still use 1. A Java char is used for each code unit. This Sun article explains it well.

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