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 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * http://glassfish.java.net/public/CDDL+GPL_1_1.html
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 * file and include the License file at packager/legal/LICENSE.txt.
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 * GPL Classpath Exception:
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package org.glassfish.jersey.internal.inject;

import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import javax.ws.rs.core.Cookie;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;

import org.glassfish.jersey.internal.LocalizationMessages;

/**
 * Proxiable wrapper for request scoped {@link HttpHeaders} instance.
 *
 * @author Jakub Podlesak (jakub.podlesak at oracle.com)
 */
public class HttpHeadersInjectee implements HttpHeaders {

    private HttpHeaders wrapped;

    /**
     * Set wrapped instance. Should be invoked on each incoming request,
     * when a new injectee instance is created by HK2.
     *
     * @param httpHeaders actual {@link HttpHeaders} instance.
     */
    public void set(final HttpHeaders httpHeaders) {
        if (wrapped != null) {
            throw new IllegalStateException(LocalizationMessages.HTTP_HEADERS_WAS_ALREADY_SET());
        }
        this.wrapped = httpHeaders;
    }

    @Override
    public List<String> getRequestHeader(String name) {
        checkState();
        return wrapped.getRequestHeader(name);
    }

    @Override
    public String getHeaderString(String name) {
        checkState();
        return wrapped.getHeaderString(name);
    }

    @Override
    public MultivaluedMap<String, String> getRequestHeaders() {
        checkState();
        return wrapped.getRequestHeaders();
    }

    @Override
    public List<MediaType> getAcceptableMediaTypes() {
        checkState();
        return wrapped.getAcceptableMediaTypes();
    }

    @Override
    public List<Locale> getAcceptableLanguages() {
        checkState();
        return wrapped.getAcceptableLanguages();
    }

    @Override
    public MediaType getMediaType() {
        checkState();
        return wrapped.getMediaType();
    }

    @Override
    public Locale getLanguage() {
        checkState();
        return wrapped.getLanguage();
    }

    @Override
    public Map<String, Cookie> getCookies() {
        checkState();
        return wrapped.getCookies();
    }

    @Override
    public Date getDate() {
        checkState();
        return wrapped.getDate();
    }

    @Override
    public int getLength() {
        checkState();
        return wrapped.getLength();
    }

    private void checkState() {
        if (wrapped == null) {
            throw new IllegalStateException(LocalizationMessages.HTTP_HEADERS_WAS_NOT_SET());
        }
    }
}