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package org.apache.juneau.http;

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

/**
 * Represents a parsed <l>Proxy-Authorization</l> HTTP request header.
 *
 * <p>
 * Authorization credentials for connecting to a proxy.
 *
 * <h5 class='figure'>Example</h5>
 * <p class='bcode w800'>
 * 	Proxy-Authorization: Basic QWxhZGRpbjpvcGVuIHNlc2FtZQ==
 * </p>
 *
 * <h5 class='topic'>RFC2616 Specification</h5>
 *
 * The Proxy-Authorization request-header field allows the client to identify itself (or its user) to a proxy which
 * requires authentication.
 * The Proxy-Authorization field value consists of credentials containing the authentication information of the user
 * agent for the proxy and/or realm of the resource being requested.
 *
 * <p class='bcode w800'>
 * 	Proxy-Authorization     = "Proxy-Authorization" ":" credentials
 * </p>
 *
 * <p>
 * The HTTP access authentication process is described in "HTTP Authentication: Basic and Digest Access Authentication".
 * Unlike Authorization, the Proxy-Authorization header field applies only to the next outbound proxy that demanded
 * authentication using the Proxy-Authenticate field.
 * When multiple proxies are used in a chain, the Proxy-Authorization header field is consumed by the first outbound
 * proxy that was expecting to receive credentials.
 * A proxy MAY relay the credentials from the client request to the next proxy if that is the mechanism by which the
 * proxies cooperatively authenticate a given request.
 *
 * <ul class='seealso'>
 * 	<li class='extlink'>{@doc RFC2616}
 * </ul>
 */
@Header("Proxy-Authorization")
public final class ProxyAuthorization extends HeaderString {

	/**
	 * Returns a parsed <c>Proxy-Authorization</c> header.
	 *
	 * @param value The <c>Proxy-Authorization</c> header string.
	 * @return The parsed <c>Proxy-Authorization</c> header, or <jk>null</jk> if the string was null.
	 */
	public static ProxyAuthorization forString(String value) {
		if (value == null)
			return null;
		return new ProxyAuthorization(value);
	}

	private ProxyAuthorization(String value) {
		super(value);
	}
}