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DSS Model contains the data model representation for DSS

There is a newer version: 6.0.d4j.2

package port.org.bouncycastle.util.io;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * Utility methods to assist with stream processing.
 */
public final class Streams {
	private static int BUFFER_SIZE = 512;

	/**
	 * Read stream fully, returning contents in a byte array.
	 *
	 * @param inStr
	 *            stream to be read.
	 * @return a byte array representing the contents of inStr.
	 * @throws IOException
	 *             in case of underlying IOException.
	 */
	public static byte[] readAll(InputStream inStr) throws IOException {
		ByteArrayOutputStream buf = new ByteArrayOutputStream();
		pipeAll(inStr, buf);
		return buf.toByteArray();
	}

	/**
	 * Fully read in buf's length in data, or up to EOF, whichever occurs first,
	 *
	 * @param inStr
	 *            the stream to be read.
	 * @param buf
	 *            the buffer to be read into.
	 * @return the number of bytes read into the buffer.
	 * @throws IOException
	 *             in case of underlying IOException.
	 */
	public static int readFully(InputStream inStr, byte[] buf) throws IOException {
		return readFully(inStr, buf, 0, buf.length);
	}

	/**
	 * Fully read in len's bytes of data into buf, or up to EOF, whichever occurs first,
	 *
	 * @param inStr
	 *            the stream to be read.
	 * @param buf
	 *            the buffer to be read into.
	 * @param off
	 *            offset into buf to start putting bytes into.
	 * @param len
	 *            the number of bytes to be read.
	 * @return the number of bytes read into the buffer.
	 * @throws IOException
	 *             in case of underlying IOException.
	 */
	public static int readFully(InputStream inStr, byte[] buf, int off, int len) throws IOException {
		int totalRead = 0;
		while (totalRead < len) {
			int numRead = inStr.read(buf, off + totalRead, len - totalRead);
			if (numRead < 0) {
				break;
			}
			totalRead += numRead;
		}
		return totalRead;
	}

	/**
	 * Write the full contents of inStr to the destination stream outStr.
	 *
	 * @param inStr
	 *            source input stream.
	 * @param outStr
	 *            destination output stream.
	 * @throws IOException
	 *             in case of underlying IOException.
	 */
	public static void pipeAll(InputStream inStr, OutputStream outStr) throws IOException {
		byte[] bs = new byte[BUFFER_SIZE];
		int numRead;
		while ((numRead = inStr.read(bs, 0, bs.length)) >= 0) {
			outStr.write(bs, 0, numRead);
		}
	}

}