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This noncompliant code example masks off the upper 24 bits of the promoted byte array element before performing the addition. The number of bits required to mask the sizes of byte and int are specified by the JLS. While this code calculates the correct result, it violates this guideline by combining bitwise and arithmetic operations on the same data.

byte[] b = new byte[] {-1, -1, -1, -1};
int result = 0;
for (int i = 0; i < 4; i++) {
  result = ((result << 8) + (b[i] & 0xff));
}

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This compliant solution masks off the upper 24 bits of the promoted byte array element. The result is then combined with result using a logical OR operation.

byte[] b = new byte[] {-1, -1, -1, -1};
int result = 0;
for (int i = 0; i < 4; i++) {
  result = ((result << 8) | (b[i] & 0xff));
}

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