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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
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package org.apache.juneau.http.response;

import static org.apache.juneau.http.response.NotModified.*;

import org.apache.juneau.http.annotation.*;

/**
 * Represents an <c>HTTP 304 Not Modified</c> response.
 *
 * <p>
 * Indicates that the resource has not been modified since the version specified by the request headers If-Modified-Since or If-None-Match.
 * In such case, there is no need to retransmit the resource since the client still has a previously-downloaded copy.
 */
@Response(code=CODE, description=MESSAGE)
public class NotModified extends HttpResponse {

	/** HTTP status code */
	public static final int CODE = 304;

	/** Default message */
	public static final String MESSAGE = "Not Modified";

	/** Reusable instance. */
	public static final NotModified INSTANCE = new NotModified();

	/**
	 * Constructor using HTTP-standard message.
	 */
	public NotModified() {
		this(MESSAGE);
	}

	/**
	 * Constructor using custom message.
	 * @param message Message to send as the response.
	 */
	public NotModified(String message) {
		super(message);
	}
}