content: package com.amadeus;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.List;
  
  /**
   * A class for constant variables.
   *
   * <pre>
   *  To use: Constants.VARIABLE
   * </pre>
   */
  public final class Constants {
  
  
    public static final String HTTPS = "https";
    public static final String HTTP = "http";
  
    public static final String USER_AGENT = "User-Agent";
    public static final String ACCEPT = "Accept";
    public static final String AUTHORIZATION = "Authorization";
    public static final String CONTENT_TYPE = "Content-Type";
    public static final String X_HTTP_METHOD_OVERRIDE = "X-HTTP-Method-Override";
  
    // Pagination
    public static final String FIRST = "first";
    public static final String LAST = "last";
    public static final String NEXT = "next";
    public static final String PREVIOUS = "previous";
  
    // Authorization
    public static final String GRANT_TYPE = "grant_type";
    public static final String CLIENT_CREDENTIALS = "client_credentials";
    public static final String CLIENT_ID = "client_id";
    public static final String CLIENT_SECRET = "client_secret";
    public static final String AUTH_URL = "/v1/security/oauth2/token";
    public static final String ACCESS_TOKEN = "access_token";
    public static final String EXPIRES_IN = "expires_in";
  
    // APIs which need an X-HTTP-Method-Override GET HEADER
    protected static final List<String> APIS_WITH_EXTRA_HEADER = new ArrayList<String>(Arrays.asList(
        "/v2/shopping/flight-offers",
        "/v1/shopping/seatmaps",
        "/v1/shopping/availability/flight-availabilities",
        "/v2/shopping/flight-offers/prediction",
        "/v1/shopping/flight-offers/pricing",
        "/v1/shopping/flight-offers/upselling"));
  
    /**
     * The caller references the constants using <tt>Consts.EMPTY_STRING</tt>,
     * and so on. Thus, the caller should be prevented from constructing objects of
     * this class, by declaring this private constructor.
     */
    private Constants() {
      throw new AssertionError();
    }
  }
  