content: /*
  * Conditions Of Use
  *
  * This software was developed by employees of the National Institute of
  * Standards and Technology (NIST), an agency of the Federal Government.
  * Pursuant to title 15 Untied States Code Section 105, works of NIST
  * employees are not subject to copyright protection in the United States
  * and are considered to be in the public domain.  As a result, a formal
  * license is not needed to use the software.
  *
  * This software is provided by NIST as a service and is expressly
  * provided "AS IS."  NIST MAKES NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED
  * OR STATUTORY, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTY OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT
  * AND DATA ACCURACY.  NIST does not warrant or make any representations
  * regarding the use of the software or the results thereof, including but
  * not limited to the correctness, accuracy, reliability or usefulness of
  * the software.
  *
  * Permission to use this software is contingent upon your acceptance
  * of the terms of this agreement
  *
  * .
  *
  */
   /****************************************************************************
   * Product of NIST/ITL Advanced Networking Technologies Division (ANTD).    *
   ****************************************************************************/
  package gov2.nist.javax2.sip.header;
  import gov2.nist.core.*;
  
  import javax2.sip.InvalidArgumentException;
  import javax2.sip.header.AcceptLanguageHeader;
  
  import java.util.Locale;
  
  /**
   * Accept Language body.
   *
   * @author M. Ranganathan
   * @version 1.2 $Revision: 1.8 $ $Date: 2009/10/18 13:46:32 $
   * @since 1.1
   *
   *
   * <pre>
   * HTTP RFC 2616 Section 14.4
   * Accept-Language = "Accept-Language" ":"
   *                         1#( language-range [ ";" "q" "=" qvalue ] )
   *       language-range  = ( ( 1*8ALPHA *( "-" 1*8ALPHA ) ) | "*" )
   *
   * </pre>
   *
   * @see AcceptLanguageList
   */
  public final class AcceptLanguage
      extends ParametersHeader
      implements AcceptLanguageHeader {
  
      /**
       * Comment for <code>serialVersionUID</code>
       */
      private static final long serialVersionUID = -4473982069737324919L;
      /** languageRange field
       */
      protected String languageRange;
  
      /** default constructor
       */
      public AcceptLanguage() {
          super(NAME);
      }
  
      /** Encode the value of this header to a string.
       *@return  encoded header as a string.
       */
      protected String encodeBody() {
          StringBuffer encoding = new StringBuffer();
          if (languageRange != null) {
              encoding.append(languageRange);
          }
          if (!parameters.isEmpty()) {
              encoding.append(SEMICOLON).append(parameters.encode());
          }
          return encoding.toString();
      }
  
      /** get the LanguageRange field
       * @return String
       */
      public String getLanguageRange() {
          return languageRange;
      }
  
      /** get the QValue field. Return -1 if the parameter has not been
       * set.
       * @return float
       */
  
      public float getQValue() {
          if (!hasParameter("q"))
              return -1;
          return ((Float) parameters.getValue("q")).floatValue();
      }
  
      /**
       * Return true if the q value has been set.
       * @since 1.0
       * @return boolean
       */
      public boolean hasQValue() {
          return hasParameter("q");
      }
  
      /**
       * Remove the q value.
       * @since 1.0
       */
      public void removeQValue() {
          removeParameter("q");
      }
  
      /**
       * Set the languageRange.
       *
       * @param languageRange is the language range to set.
       *
       */
      public void setLanguageRange(String languageRange) {
          this.languageRange = languageRange.trim();
      }
  
      /**
       * Sets q-value for media-range in AcceptLanguageHeader. Q-values allow the
       *
       * user to indicate the relative degree of preference for that media-range,
       *
       * using the qvalue scale from 0 to 1. If no q-value is present, the
       *
       * media-range should be treated as having a q-value of 1.
       *
       *
       *
       * @param q The new float value of the q-value, a value of -1 resets
       * the qValue.
       *
       * @throws InvalidArgumentException if the q parameter value is not
       *
       * <code>-1</code> or between <code>0 and 1</code>.
       *
       */
      public void setQValue(float q) throws InvalidArgumentException {
          if (q < 0.0 || q > 1.0)
              throw new InvalidArgumentException("qvalue out of range!");
          if (q == -1)
              this.removeParameter("q");
          else
              this.setParameter(new NameValue("q", Float.valueOf(q)));
      }
  
      /**
       * Gets the language value of the AcceptLanguageHeader.
       *
       *
       *
       * @return the language Locale value of this AcceptLanguageHeader
       *
       */
      public Locale getAcceptLanguage() {
          if (this.languageRange == null)
              return null;
          else {
              int dash = languageRange.indexOf('-');
              if (dash>=0) {
                  return new Locale( languageRange.substring(0,dash), languageRange.substring(dash+1) );
              } else return new Locale( this.languageRange );
          }
      }
  
      /**
       * Sets the language parameter of this AcceptLanguageHeader.
       *
       *
       *
       * @param language - the new Locale value of the language of
       *
       * AcceptLanguageHeader
       *
       *
       */
      public void setAcceptLanguage(Locale language) {
          // JvB: need to take sub-tag into account
          if ( "".equals(language.getCountry())) {
              this.languageRange = language.getLanguage();
          } else {
              this.languageRange = language.getLanguage() + '-' + language.getCountry();
          }
      }
  
  }
  