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Non-numeric primitive casting

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The boolean type cannot be cast to/from any other primitive type.

A char can be cast to/from any numeric type by using the code-point mappings specified by Unicode. A char is represented in memory as an unsigned 16-bit integer value (2 bytes), so casting to byte (1 byte) will drop 8 of those bits (this is safe for ASCII characters). The utility methods of the Character class use int (4 bytes) to transfer to/from code-point values, but a short (2 bytes) would also suffice for storing a Unicode code-point. 

int badInt   = (int)  true; // Compiler error: incompatible types

char char1   = (char)   65; // A
byte byte1   = (byte)  'A'; // 65
short short1 = (short) 'A'; // 65
int int1     = (int)   'A'; // 65

char char2   = (char) 8253; // ‽
byte byte2   = (byte)  '‽'; // 61 (truncated code-point into the ASCII range)
short short2 = (short) '‽'; // 8253
int int2     = (int)   '‽'; // 8253
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Type Conversion:
* Type Conversion
* Numeric primitive casting
* Basic Numeric Promotion
* Non-numeric primitive casting
* Object casting
* Testing if an object can be cast using instanceof
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