public abstract class OutputStream extends Object implements Closeable, Flushable
Applications that need to define a subclass of
OutputStream
must always provide at least a method
that writes one byte of output.
BufferedOutputStream
,
ByteArrayOutputStream
,
DataOutputStream
,
FilterOutputStream
,
InputStream
,
write(int)
Constructor and Description |
---|
OutputStream() |
Modifier and Type | Method and Description |
---|---|
void |
close()
Closes this output stream and releases any system resources
associated with this stream.
|
void |
flush()
Flushes this output stream and forces any buffered output bytes
to be written out.
|
void |
write(byte[] b)
Writes
b.length bytes from the specified byte array
to this output stream. |
void |
write(byte[] b,
int off,
int len)
Writes
len bytes from the specified byte array
starting at offset off to this output stream. |
abstract void |
write(int b)
Writes the specified byte to this output stream.
|
public abstract void write(int b) throws IOException
write
is that one byte is written
to the output stream. The byte to be written is the eight
low-order bits of the argument b
. The 24
high-order bits of b
are ignored.
Subclasses of OutputStream
must provide an
implementation for this method.
b
- the byte
.IOException
- if an I/O error occurs. In particular,
an IOException
may be thrown if the
output stream has been closed.public void write(byte[] b) throws IOException
b.length
bytes from the specified byte array
to this output stream. The general contract for write(b)
is that it should have exactly the same effect as the call
write(b, 0, b.length)
.b
- the data.IOException
- if an I/O error occurs.write(byte[], int, int)
public void write(byte[] b, int off, int len) throws IOException
len
bytes from the specified byte array
starting at offset off
to this output stream.
The general contract for write(b, off, len)
is that
some of the bytes in the array b
are written to the
output stream in order; element b[off]
is the first
byte written and b[off+len-1]
is the last byte written
by this operation.
The write
method of OutputStream
calls
the write method of one argument on each of the bytes to be
written out. Subclasses are encouraged to override this method and
provide a more efficient implementation.
If b
is null
, a
NullPointerException
is thrown.
If off
is negative, or len
is negative, or
off+len
is greater than the length of the array
b
, then an IndexOutOfBoundsException is thrown.
b
- the data.off
- the start offset in the data.len
- the number of bytes to write.IOException
- if an I/O error occurs. In particular,
an IOException
is thrown if the output
stream is closed.public void flush() throws IOException
flush
is
that calling it is an indication that, if any bytes previously
written have been buffered by the implementation of the output
stream, such bytes should immediately be written to their
intended destination.
If the intended destination of this stream is an abstraction provided by the underlying operating system, for example a file, then flushing the stream guarantees only that bytes previously written to the stream are passed to the operating system for writing; it does not guarantee that they are actually written to a physical device such as a disk drive.
The flush
method of OutputStream
does nothing.
flush
in interface Flushable
IOException
- if an I/O error occurs.public void close() throws IOException
close
is that it closes the output stream. A closed stream cannot perform
output operations and cannot be reopened.
The close
method of OutputStream
does nothing.
close
in interface Closeable
close
in interface AutoCloseable
IOException
- if an I/O error occurs. Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
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