/*
 * Copyright 2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.gradle.api;

/**
 * <p>A {@code Transformer} transforms objects of type.</p>
 *
 * <p>Implementations are free to return new objects or mutate the incoming value.</p>
 *
 * @param <OUT> The type the value is transformed to.
 * @param <IN> The type of the value to be transformed.
 */
public interface Transformer<OUT, IN> {
    /**
     * Transforms the given object, and returns the transformed value.
     *
     * @param in The object to transform.
     * @return The transformed object.
     */
    OUT transform(IN in);
}

/*
 * Copyright 2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.gradle.api;

import javax.annotation.Nullable;

/**
 * <p>A {@code Transformer} transforms objects of type.</p>
 *
 * <p>Implementations are free to return new objects or mutate the incoming value.</p>
 *
 * @param <OUT> The type the value is transformed to.
 * @param <IN> The type of the value to be transformed.
 */
public interface Transformer<OUT, IN> {
    /**
     * Transforms the given object, and returns the transformed value.
     *
     * @param in The object to transform.
     * @return The transformed object.
     */
    OUT transform(@Nullable IN in);
}

--- 
+++ 
@@ -15,8 +15,6 @@
  */
 package org.gradle.api;
 
-import javax.annotation.Nullable;
-
 /**
  * <p>A {@code Transformer} transforms objects of type.</p>
  *
@@ -32,5 +30,5 @@
      * @param in The object to transform.
      * @return The transformed object.
      */
-    OUT transform(@Nullable IN in);
+    OUT transform(IN in);
 }
Remove `@Nullable` for backwards compatibility with Kotlin API
