code: public void applySourceConditionToRequest(final HttpURLConnection request) {    
          if (!Utility.isNullOrEmpty(this.leaseID)) {
              // Unsupported
              throw new IllegalArgumentException(SR.LEASE_CONDITION_ON_SOURCE);
          }
  
          if (this.ifModifiedSinceDate != null) {
              request.setRequestProperty(
                      Constants.HeaderConstants.SOURCE_IF_MODIFIED_SINCE_HEADER,
                      Utility.getGMTTime(this.ifModifiedSinceDate));
          }
  
          if (this.ifUnmodifiedSinceDate != null) {
              request.setRequestProperty(Constants.HeaderConstants.SOURCE_IF_UNMODIFIED_SINCE_HEADER,
                      Utility.getGMTTime(this.ifUnmodifiedSinceDate));
          }
  
          if (!Utility.isNullOrEmpty(this.ifMatchETag)) {
              request.setRequestProperty(
                      Constants.HeaderConstants.SOURCE_IF_MATCH_HEADER,
                      this.ifMatchETag);
          }
  
          if (!Utility.isNullOrEmpty(this.ifNoneMatchETag)) {
              request.setRequestProperty(
                      Constants.HeaderConstants.SOURCE_IF_NONE_MATCH_HEADER,
                      this.ifNoneMatchETag);
          }
      }
docs: RESERVED FOR INTERNAL USE. Applies the source access conditions to the request.
  
  @param request
  A <code>java.net.HttpURLConnection</code> object that represents the request
  to which the condition is being applied.