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* accompanied this code).
*
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package java.io;
The class implements a buffered output stream. By setting up such
an output stream, an application can write bytes to the underlying
output stream without necessarily causing a call to the underlying
system for each byte written.
Author: Arthur van Hoff Since: 1.0
/**
* The class implements a buffered output stream. By setting up such
* an output stream, an application can write bytes to the underlying
* output stream without necessarily causing a call to the underlying
* system for each byte written.
*
* @author Arthur van Hoff
* @since 1.0
*/
public class BufferedOutputStream extends FilterOutputStream {
The internal buffer where data is stored.
/**
* The internal buffer where data is stored.
*/
protected byte buf[];
The number of valid bytes in the buffer. This value is always in the range 0 through buf.length; elements buf[0] through buf[count-1] contain valid byte data. /**
* The number of valid bytes in the buffer. This value is always
* in the range {@code 0} through {@code buf.length}; elements
* {@code buf[0]} through {@code buf[count-1]} contain valid
* byte data.
*/
protected int count;
Creates a new buffered output stream to write data to the
specified underlying output stream.
Params: - out – the underlying output stream.
/**
* Creates a new buffered output stream to write data to the
* specified underlying output stream.
*
* @param out the underlying output stream.
*/
public BufferedOutputStream(OutputStream out) {
this(out, 8192);
}
Creates a new buffered output stream to write data to the
specified underlying output stream with the specified buffer
size.
Params: - out – the underlying output stream.
- size – the buffer size.
Throws: - IllegalArgumentException – if size <= 0.
/**
* Creates a new buffered output stream to write data to the
* specified underlying output stream with the specified buffer
* size.
*
* @param out the underlying output stream.
* @param size the buffer size.
* @exception IllegalArgumentException if size <= 0.
*/
public BufferedOutputStream(OutputStream out, int size) {
super(out);
if (size <= 0) {
throw new IllegalArgumentException("Buffer size <= 0");
}
buf = new byte[size];
}
Flush the internal buffer /** Flush the internal buffer */
private void flushBuffer() throws IOException {
if (count > 0) {
out.write(buf, 0, count);
count = 0;
}
}
Writes the specified byte to this buffered output stream.
Params: - b – the byte to be written.
Throws: - IOException – if an I/O error occurs.
/**
* Writes the specified byte to this buffered output stream.
*
* @param b the byte to be written.
* @exception IOException if an I/O error occurs.
*/
@Override
public synchronized void write(int b) throws IOException {
if (count >= buf.length) {
flushBuffer();
}
buf[count++] = (byte)b;
}
Writes len bytes from the specified byte array
starting at offset off to this buffered output stream.
Ordinarily this method stores bytes from the given array into this
stream's buffer, flushing the buffer to the underlying output stream as
needed. If the requested length is at least as large as this stream's
buffer, however, then this method will flush the buffer and write the
bytes directly to the underlying output stream. Thus redundant
BufferedOutputStreams will not copy data unnecessarily.
Params: - 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.
/**
* Writes <code>len</code> bytes from the specified byte array
* starting at offset <code>off</code> to this buffered output stream.
*
* <p> Ordinarily this method stores bytes from the given array into this
* stream's buffer, flushing the buffer to the underlying output stream as
* needed. If the requested length is at least as large as this stream's
* buffer, however, then this method will flush the buffer and write the
* bytes directly to the underlying output stream. Thus redundant
* <code>BufferedOutputStream</code>s will not copy data unnecessarily.
*
* @param b the data.
* @param off the start offset in the data.
* @param len the number of bytes to write.
* @exception IOException if an I/O error occurs.
*/
@Override
public synchronized void write(byte b[], int off, int len) throws IOException {
if (len >= buf.length) {
/* If the request length exceeds the size of the output buffer,
flush the output buffer and then write the data directly.
In this way buffered streams will cascade harmlessly. */
flushBuffer();
out.write(b, off, len);
return;
}
if (len > buf.length - count) {
flushBuffer();
}
System.arraycopy(b, off, buf, count, len);
count += len;
}
Flushes this buffered output stream. This forces any buffered
output bytes to be written out to the underlying output stream.
Throws: - IOException – if an I/O error occurs.
See Also:
/**
* Flushes this buffered output stream. This forces any buffered
* output bytes to be written out to the underlying output stream.
*
* @exception IOException if an I/O error occurs.
* @see java.io.FilterOutputStream#out
*/
@Override
public synchronized void flush() throws IOException {
flushBuffer();
out.flush();
}
}