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Shared libraries, common parent for both BIMserver and BimServerClientLib

There is a newer version: 2.0.0

package org.bimserver.utils;

import static com.google.common.base.Preconditions.checkNotNull;

import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;

// Slightly modified (not final) copy from Guava
public class CountingInputStream extends FilterInputStream {

	private long count;
	private long mark = -1;

	/**
	 * Wraps another input stream, counting the number of bytes read.
	 *
	 * @param in
	 *            the input stream to be wrapped
	 */
	public CountingInputStream(InputStream in) {
		super(checkNotNull(in));
	}

	/** Returns the number of bytes read. */
	public long getCount() {
		return count;
	}

	@Override
	public int read() throws IOException {
		int result = in.read();
		if (result != -1) {
			count++;
		}
		return result;
	}

	@Override
	public int read(byte[] b, int off, int len) throws IOException {
		int result = in.read(b, off, len);
		if (result != -1) {
			count += result;
		}
		return result;
	}

	@Override
	public long skip(long n) throws IOException {
		long result = in.skip(n);
		count += result;
		return result;
	}

	@Override
	public synchronized void mark(int readlimit) {
		in.mark(readlimit);
		mark = count;
		// it's okay to mark even if mark isn't supported, as reset won't work
	}

	@Override
	public synchronized void reset() throws IOException {
		if (!in.markSupported()) {
			throw new IOException("Mark not supported");
		}
		if (mark == -1) {
			throw new IOException("Mark not set");
		}

		in.reset();
		count = mark;
	}
}