java.io · java.base · since Java 1.0

OutputStream

declaration

public abstract class OutputStream implements Closeable, Flushable

The abstract byte sink. Buffer it, write, flush before checking results, close via try-with-resources (which flushes).

Key methods

`void write(int b) / write(byte[] b, int off, int len)`	Byte and block writes.
`void flush()`	Push buffered bytes down the chain.