java/src/main/com/google/appengine/api/images/Rotate.java

   1 // Copyright 2009 Google Inc. All Rights Reserved.
   2
   3 package com.google.appengine.api.images;
   4
   5 /**
   6  * A transform that will rotate an image by a multiple of 90 degrees.
   7  *
   8  */
   9 final class Rotate extends Transform {
  10
  11   private static final long serialVersionUID = -8585289244565451429L;
  12
  13   private final int degrees;
  14
  15   /**
  16    * Creates a Rotate transform that rotates an image by {@code degrees} degrees.
  17    * @param degrees number of degrees to rotate
  18    * @throws IllegalArgumentException If {@code degrees} is not divisible by 90
  19   */
  20   Rotate(int degrees) {
  21     if ((degrees % 90) != 0) {
  22       throw new IllegalArgumentException("degrees must be a multiple of 90");
  23     }
  24     this.degrees = ((degrees % 360) + 360) % 360;
  25   }
  26
  27   /** {@inheritDoc} */
  28   @Override
  29   void apply(ImagesServicePb.ImagesTransformRequest.Builder request) {
  30     request.addTransform(ImagesServicePb.Transform.newBuilder().setRotate(degrees));
  31   }
  32 }