package ar.com.hjg.pngj.chunks;

import ar.com.hjg.pngj.ImageInfo;

/**
 * PNG chunk type (abstract) that does not allow multiple instances in same
 * image.
 */
public abstract class PngChunkSingle extends PngChunk {

	protected PngChunkSingle(final String id, final ImageInfo imgInfo) {
		super(id, imgInfo);
	}

	@Override
	public final boolean allowsMultiple() {
		return false;
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + (id == null ? 0 : id.hashCode());
		return result;
	}

	@Override
	public boolean equals(final Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		final PngChunkSingle other = (PngChunkSingle) obj;
		if (id == null) {
			if (other.id != null)
				return false;
		} else if (!id.equals(other.id))
			return false;
		return true;
	}

}
