Why does ByteArrayOutputStream use int?

Question

Maybe someone can help me understand, because I feel that I am missing something that is likely to affect my program.

I am using ByteArrayOutputStream. If I have not missed something huge, then this class should create a byte [] array for other uses.

However, the "simple" write function in BAOS accepts int not bytes ( ByteArrayOutputStream.write ).

According to this ( Primitive Data Types ), in Java, int is a 32-bit data type, and a byte is an 8-bit data type.

If I write this code ...

int i = 32;
byte b = i;

I get a warning about possible lossy transformations requiring a change to this ...

int i = 32;
byte b = (byte)i;

I am really confused about the entry (int) ...

Answer 1

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// Write a single byte 0. Works with current code, wouldn't work if the parameter
// were byte.
stream.write(0);

, , 0 int, byte. :

// Ugly, but would have been okay with write(byte).
stream.write((byte) 0);

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Answer 2

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Ingo:

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Answer 3

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