Casting long to byte in Java -

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i unable understand following:

in java, 

long l = 130l;   byte b = (byte)l;

if print value of b, why -126? bit representation of long l?

bytes signed in java - range of values -128 127 inclusive.

the bit pattern 130 long, when truncated 8 bits, bit pattern -126 byte.

as example:

int x = 255; byte b = (byte) x; // b -1

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