Merge main branch to local branch

README.md

@@ -1,11 +1,5 @@
 # TensorFlow for Java
 
-***!!! IMPORTANT NOTICE !!! This repository is UNDER CONSTRUCTION and does not yet host the code of the 
-offical TensorFlow Java artifacts!***
-
-***Please refer to the [TensorFlow Java module](https://github.com/tensorflow/tensorflow/tree/master/tensorflow/java) 
-of the main repository for the actual code.***
-
 ## Welcome to the Java world of TensorFlow!
 
 TensorFlow can run on any JVM for building, training and running machine learning models. It comes with 
@@ -30,19 +24,10 @@ The following describes the layout of the repository and its different artifacts
     TensorFlow and just want a thin layer to access the TensorFlow runtime from the JVM 
 
 * `tensorflow-framework`
-  * Complete but fairly primitive API for building and training neural networks with TensorFlow
-  * Intended audience: expert neural network developers who prefer to make explicit, detailed decisions 
-    about their models and training algorithms
-
-* `tensorflow-keras` (early WIP; only defined in `dev` profile)
-  * Partially covers the framework API to allow simpler definition of models and training algorithms
-  * Intended to be familiar if you know the Python Keras API, but prioritizes clean, idiomatic Java 
-    over fidelity to Python
-  * Provides defaults based on common best practices
-  * Allows developers to selectively be more explicit by overriding defaults or dipping into the framework API
-  * Intended audience: neural network developers across the spectrum from beginner to expert who prefer to
-    rely mostly on best-practice defaults and then selectively fine-tune
-
+  * Primary API for building and training neural networks with TensorFlow
+  * Intended audience: neural network developers
+  * For more information: [tensorflow-framework/README.md](tensorflow-framework/README.md)
+
 * `ndarray`
   * Generic utility library for n-dimensional data I/O operations
   * Used by TensorFlow but does not depend on TensorFlow
@@ -172,8 +157,6 @@ This table shows the mapping between different version of TensorFlow for Java an
 
 | TensorFlow Java Version  | TensorFlow Version |
 | ------------- | ------------- |
-| 0.1.0-SNAPSHOT  | 2.2.0  |
-| 0.2.0-SNAPSHOT  | 2.3.1  |
 | 0.2.0  | 2.3.1  |
 | 0.3.0-SNAPSHOT  | 2.3.1  |
 

pom.xml

@@ -119,19 +119,6 @@
   </dependencyManagement>
 
   <profiles>
-    <!--
-    Developing profile
-        The 'dev' profile is used for local development or PR compilation check only.
-        Here, we enable the `tensorflow-keras` module only under this profile, until
-        it is mature enough for being deployed and distributed for the end users.
-    -->
-    <profile>
-      <id>dev</id>
-      <modules>
-        <!-- Disabled while the library is still empty -->
-        <!--module>tensorflow-keras</module-->
-      </modules>
-    </profile>
     <!--
     Deploying profile
         Build the Javadoc when deploying

tensorflow-core/tensorflow-core-api/src/bazel/api_def/api_def_LeakyRelu.pbtxt

@@ -1,5 +1,6 @@
 op {
   graph_op_name: "LeakyRelu"
+  visibility: VISIBLE
   endpoint {
     name: "nn.LeakyRelu"
   }

tensorflow-core/tensorflow-core-api/src/gen/annotations/org/tensorflow/op/NnOps.java

@@ -59,6 +59,7 @@
 import org.tensorflow.op.nn.FusedResizeAndPadConv2d;
 import org.tensorflow.op.nn.InTopK;
 import org.tensorflow.op.nn.L2Loss;
+import org.tensorflow.op.nn.LeakyRelu;
 import org.tensorflow.op.nn.LearnedUnigramCandidateSampler;
 import org.tensorflow.op.nn.LocalResponseNormalization;
 import org.tensorflow.op.nn.LogSoftmax;
@@ -1226,6 +1227,19 @@ public <T extends TNumber> L2Loss<T> l2Loss(Operand<T> t) {
     return L2Loss.create(scope, t);
   }
 
+  /**
+   * Computes rectified linear: `max(features, features * alpha)`.
+   *
+   * @param <T> data type for {@code activations()} output
+   * @param features
+   * @param options carries optional attributes values
+   * @return a new instance of LeakyRelu
+   */
+  public <T extends TNumber> LeakyRelu<T> leakyRelu(Operand<T> features,
+      LeakyRelu.Options... options) {
+    return LeakyRelu.create(scope, features, options);
+  }
+
   /**
    * Generates labels for candidate sampling with a learned unigram distribution.
    *  <p>

tensorflow-core/tensorflow-core-api/src/gen/java/org/tensorflow/op/nn/LeakyRelu.java

@@ -33,6 +33,7 @@
  * 
  * @param <T> data type for {@code activations()} output
  */
+@Operator(group = "nn")
 public final class LeakyRelu<T extends TNumber> extends RawOp implements Operand<T> {
 
   /**

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/SavedModelBundle.java

@@ -429,7 +429,7 @@ opts, runOpts, new BytePointer(exportDir), new PointerPointer(tags),
   }
 
   private static void validateTags(String[] tags) {
-    if (tags == null || tags.length == 0 || Arrays.stream(tags).anyMatch(t -> t == null || t.isEmpty())) {
+    if (tags == null || Arrays.stream(tags).anyMatch(t -> t == null || t.isEmpty())) {
       throw new IllegalArgumentException("Invalid tags: " + Arrays.toString(tags));
     }
   }

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/types/TBfloat16.java

@@ -30,7 +30,7 @@
 import org.tensorflow.ndarray.NdArray;
 import org.tensorflow.ndarray.StdArrays;
 import org.tensorflow.ndarray.impl.dense.FloatDenseNdArray;
-import org.tensorflow.types.family.TNumber;
+import org.tensorflow.types.family.TFloating;
 
 /**
  * Brain 16-bit float tensor type.
@@ -48,7 +48,7 @@
  * <p>Note that some CPUs support the bfloat16 format natively, which can result in faster
  * computation compared to {@link TFloat16} when GPUs are not used.
  */
-public interface TBfloat16 extends FloatNdArray, TNumber {
+public interface TBfloat16 extends FloatNdArray, TFloating {
   /** readable-name for the data type */
   static final String NAME = "BFLOAT16";
 

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/types/TFloat16.java

@@ -30,7 +30,7 @@
 import org.tensorflow.ndarray.NdArray;
 import org.tensorflow.ndarray.StdArrays;
 import org.tensorflow.ndarray.impl.dense.FloatDenseNdArray;
-import org.tensorflow.types.family.TNumber;
+import org.tensorflow.types.family.TFloating;
 
 /**
  * IEEE-754 half-precision 16-bit float tensor type.
@@ -45,7 +45,7 @@
  * most CPUs do not support this format natively. For CPU computation on 16-bit floats, the {@link
  * TBfloat16} tensor type might be a better option.
  */
-public interface TFloat16 extends FloatNdArray, TNumber {
+public interface TFloat16 extends FloatNdArray, TFloating {
 
   /** readable-name for the data type */
   static final String NAME = "FLOAT16";

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/types/TFloat32.java

@@ -29,10 +29,10 @@
 import org.tensorflow.ndarray.NdArray;
 import org.tensorflow.ndarray.StdArrays;
 import org.tensorflow.ndarray.impl.dense.FloatDenseNdArray;
-import org.tensorflow.types.family.TNumber;
+import org.tensorflow.types.family.TFloating;
 
 /** IEEE-754 single-precision 32-bit float tensor type. */
-public interface TFloat32 extends FloatNdArray, TNumber {
+public interface TFloat32 extends FloatNdArray, TFloating {
 
   /** readable-name for the data type */
   static final String NAME = "FLOAT";

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/types/TFloat64.java

@@ -29,10 +29,11 @@
 import org.tensorflow.ndarray.NdArray;
 import org.tensorflow.ndarray.StdArrays;
 import org.tensorflow.ndarray.impl.dense.DoubleDenseNdArray;
-import org.tensorflow.types.family.TNumber;
+import org.tensorflow.types.family.TFloating;
+
 
 /** IEEE-754 double-precision 64-bit float tensor type. */
-public interface TFloat64 extends DoubleNdArray, TNumber {
+public interface TFloat64 extends DoubleNdArray, TFloating {
 
   /** readable-name for the data type */
   static final String NAME = "DOUBLE";

tensorflow-core/tensorflow-core-api/src/main/java/org/tensorflow/types/family/TFloating.java

@@ -0,0 +1,19 @@
+package org.tensorflow.types.family;
+
+/**
+ * Marker interface for floating point tensor types.
+ *
+ * <p>Operations that only accepts floating point values as some of their operands enforce that the tensor
+ * types for these operands to be bound to this interface. For example:
+ *
+ * <pre>{@code
+ * TFloat32 tensor1 = TFloat32.vectorOf(1, 2, 3);
+ * TBool tensor2 = TBool.vectorOf(true, false, true);
+ *
+ * Ops tf = Ops.create();
+ * Exponential<TFloat32> exp = new Exponential<>(tf);
+ * exp.call(tf.constant(tensor1));  // OK
+ * exp.call(tf.constant(tensor2));  // Compilation failure
+ * }</pre>
+ */
+public interface TFloating extends TNumber {}

tensorflow-core/tensorflow-core-api/src/test/java/org/tensorflow/SavedModelBundleTest.java

@@ -262,10 +262,7 @@ public void cannotExportMultipleFunctionsWithSameSignatureKey() throws IOExcepti
   @Test
   public void cannotExportOrImportInvalidTags() {
     assertThrows(IllegalArgumentException.class, () ->
-        SavedModelBundle.loader("/").withTags()
-    );
-    assertThrows(IllegalArgumentException.class, () ->
-        SavedModelBundle.loader("/").withTags(new String[]{})
+        SavedModelBundle.loader("/").withTags(null)
     );
     assertThrows(IllegalArgumentException.class, () ->
         SavedModelBundle.loader("/").withTags(new String[]{"tag", null})
@@ -274,10 +271,7 @@ public void cannotExportOrImportInvalidTags() {
         SavedModelBundle.loader("/").withTags(new String[]{"tag", ""})
     );
     assertThrows(IllegalArgumentException.class, () ->
-        SavedModelBundle.exporter("/").withTags()
-    );
-    assertThrows(IllegalArgumentException.class, () ->
-        SavedModelBundle.exporter("/").withTags(new String[]{})
+        SavedModelBundle.exporter("/").withTags(null)
     );
     assertThrows(IllegalArgumentException.class, () ->
         SavedModelBundle.exporter("/").withTags(new String[]{"tag", null})

tensorflow-framework/README.md

@@ -0,0 +1,28 @@
+# Framework API
+
+This is the primary Java API for building and training neural networks with TensorFlow.
+This API deliberately mirrors the overall structure of Python Keras. However, it
+is intended as a comfortable, idiomatic Java API for developers who may or may not
+be familiar with Keras.
+
+This API is intended to provide convenient, sensible defaults, while still allowing you to 
+exercise fine control over the details of your model, training, and inference when necessary.
+
+More specifically, the following goals drive API evolution:
+
+* If either you know how to implement a model in the Python Keras API, or you are reimplementing an 
+  existing Python Keras model in Java, you should be able to cleanly and naturally follow the same 
+  high-level structure in the framework API.
+
+* Also, given some familiarity with patterns followed throughout the framework API, you should be 
+  able to easily translate every detail of a Python Keras implementation into the framework API.
+
+* However, the framework API is not intended to literally mimic the Python Keras API. Rather, it 
+  should expose the same capabilities in an API that feels natural and idiomatic to a Java 
+  programmer who does not know Keras. If we ever find ourselves unable to reconcile this goal with 
+  easy translation from Python Keras, we may split out a Keras layer.
+
+* Also, the framework API should support fine control over all aspects of modeling, training, and 
+  inference. Unlike with Python Keras, we want this to feel like staying in the same API rather 
+  than diving into a separate layer. But here again, if we are ever unable to reconcile this goal 
+  with easy translation from Python Keras, we may split the framework API into two layers.

tensorflow-framework/src/main/java/org/tensorflow/framework/activations/Activation.java

@@ -0,0 +1,68 @@
+/* Copyright 2020 The TensorFlow Authors. All Rights Reserved.
+
+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.tensorflow.framework.activations;
+
+import org.tensorflow.Operand;
+import org.tensorflow.op.Ops;
+import org.tensorflow.types.family.TNumber;
+
+/**
+ * Abstract base class for Activations
+ *
+ * <p><b>Note:</b> The {@link #tf} attribute must be set prior to invoking the call method. See
+ * {@link #setTF(Ops)} and the constructor {@link #Activation(Ops)}.
+ *
+ * @param <T> the data type of the activation
+ */
+public abstract class Activation<T extends TNumber> {
+
+  /** The TensorFlow Ops */
+  protected Ops tf;
+
+  /**
+   * Creates the abstract class for an Activation
+   *
+   * @param tf the TensorFlow Ops
+   */
+  protected Activation(Ops tf) {
+    this.tf = tf;
+  }
+
+  /**
+   * Sets the TensorFlow Ops
+   *
+   * @param tf the TensorFlow Ops
+   */
+  protected void setTF(Ops tf) {
+    this.tf = tf;
+  }
+
+  /**
+   * Gets the TensorFlow Ops
+   *
+   * @return the TensorFlow Ops
+   */
+  protected Ops getTF() {
+    return this.tf;
+  }
+
+  /**
+   * Gets the calculation operation for the activation.
+   *
+   * @param input the input tensor
+   * @return The operand for the activation
+   */
+  public abstract Operand<T> call(Operand<T> input);
+}