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*
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*
* Note that this class NEVER closes the underlying stream, even when close * gets called. Instead, the stream will be marked as closed and no further * output will be permitted. * * @since 4.0 */ public class ContentLengthOutputStream extends OutputStream { private final SessionOutputBuffer buffer; private final OutputStream outputStream; /** * The maximum number of bytes that can be written the stream. Subsequent * write operations will be ignored. */ private final long contentLength; /** Total bytes written */ private long total = 0; /** True if the stream is closed. */ private boolean closed = false; /** * Default constructor. * * @param buffer Session output buffer * @param outputStream Output stream * @param contentLength The maximum number of bytes that can be written to * the stream. Subsequent write operations will be ignored. * * @since 4.0 */ public ContentLengthOutputStream(final SessionOutputBuffer buffer, final OutputStream outputStream, final long contentLength) { super(); this.buffer = Args.notNull(buffer, "Session output buffer"); this.outputStream = Args.notNull(outputStream, "Output stream"); this.contentLength = Args.notNegative(contentLength, "Content length"); } /** *
Does not close the underlying socket output.
* * @throws IOException If an I/O problem occurs. */ @Override public void close() throws IOException { if (!this.closed) { this.closed = true; this.buffer.flush(this.outputStream); } } @Override public void flush() throws IOException { this.buffer.flush(this.outputStream); } @Override public void write(final byte[] b, final int off, final int len) throws IOException { if (this.closed) { throw new StreamClosedException("Stream already closed"); } if (this.total < this.contentLength) { final long max = this.contentLength - this.total; int chunk = len; if (chunk > max) { chunk = (int) max; } this.buffer.write(b, off, chunk, this.outputStream); this.total += chunk; } } @Override public void write(final byte[] b) throws IOException { write(b, 0, b.length); } @Override public void write(final int b) throws IOException { if (this.closed) { throw new StreamClosedException("Stream already closed"); } if (this.total < this.contentLength) { this.buffer.write(b, this.outputStream); this.total++; } } }