java.io
Class OutputStreamjava.lang.Object | +--java.io.OutputStream
- Direct Known Subclasses:
- ByteArrayOutputStream, FileOutputStream, FilterOutputStream, ObjectOutputStream, OutputStream, PipedOutputStream
- public abstract class OutputStream
- extends Object
This abstract class is the superclass of all classes representing an output stream of bytes. An output stream accepts output bytes and sends them to some sink.
Applications that need to define a subclass of OutputStream must always provide at least a method that writes one byte of output.
- Since:
- JDK1.0
- See Also:
- BufferedOutputStream, ByteArrayOutputStream, DataOutputStream, FilterOutputStream, InputStream, write(int)
Constructor Summary
OutputStream()
Method Summary
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.
Methods inherited from class java.lang.Object clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
OutputStream
public OutputStream()
Method Detail
write
public abstract void write(int b) throws IOException
- Writes the specified byte to this output stream. The general contract for 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.
- Parameters:
- b - the byte.
- Throws:
- IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.
write
public void write(byte[] b) throws IOException
- Writes 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).
- Parameters:
- b - the data.
- Throws:
- IOException - if an I/O error occurs.
- See Also:
- write(byte[], int, int)
write
public void write(byte[] b, int off, int len) throws IOException
- Writes 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.
- Parameters:
- b - the data.
- off - the start offset in the data.
- len - the number of bytes to write.
- Throws:
- IOException - if an I/O error occurs. In particular, an IOException is thrown if the output stream is closed.
flush
public void flush() throws IOException
- Flushes this output stream and forces any buffered output bytes to be written out. The general contract of 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.
The flush method of OutputStream does nothing.
- Throws:
- IOException - if an I/O error occurs.
close
public void close() throws IOException
- Closes this output stream and releases any system resources associated with this stream. The general contract of 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.
- Throws:
- IOException - if an I/O error occurs.