1 package com.bumptech.glide.load; 2 3 import com.bumptech.glide.load.engine.Resource; 4 5 /** 6 * A class for performing an arbitrary transformation on a resource. 7 * 8 * @param <T> The type of the resource being transformed. 9 */ 10 public interface Transformation<T> { 11 12 /** 13 * Transforms the given resource and returns the transformed resource. 14 * 15 * <p> 16 * Note - If the original resource object is not returned, the original resource will be recycled and it's 17 * internal resources may be reused. This means it is not safe to rely on the original resource or any internal 18 * state of the original resource in any new resource that is created. Usually this shouldn't occur, but if 19 * absolutely necessary either the original resource object can be returned with modified internal state, or 20 * the data in the original resource can be copied into the transformed resource. 21 * </p> 22 * 23 * @param resource The resource to transform. 24 * @param outWidth The width of the view or target the resource will be displayed in. 25 * @param outHeight The height of the view or target the resource will be displayed in. 26 * @return The transformed resource. 27 */ 28 Resource<T> transform(Resource<T> resource, int outWidth, int outHeight); 29 30 /** 31 * A method to get a unique identifier for this particular transformation that can be used as part of a cache key. 32 * The fully qualified class name for this class is appropriate if written out, but getClass().getName() is not 33 * because the name may be changed by proguard. 34 * 35 * <p> 36 * If this transformation does not affect the data that will be stored in cache, returning an empty string here 37 * is acceptable. 38 * </p> 39 * 40 * @return A string that uniquely identifies this transformation. 41 */ 42 String getId(); 43 } 44
