Add forceInitialize to reinitialize session

Signed-off-by: Ryan Nett <[email protected]>

Author: rnett

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

@@ -59,7 +59,6 @@
 import org.tensorflow.internal.c_api.TF_Tensor;
 import org.tensorflow.ndarray.Shape;
 import org.tensorflow.op.Scope;
-import org.tensorflow.op.core.Constant;
 import org.tensorflow.proto.framework.AttrValue;
 import org.tensorflow.proto.framework.AttrValue.ListValue;
 import org.tensorflow.proto.framework.DataType;

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

@@ -145,6 +145,7 @@ public void close() {
    * Execute the graph's initializers.
    *
    * <p>This runs any ops that have been created with an init scope.
+   * @throws IllegalStateException if the session has already been initialized
    */
   public synchronized void initialize() {
     if (hasInitialized) {
@@ -165,6 +166,26 @@ public synchronized void initialize() {
     hasInitialized = true;
   }
 
+  /**
+   * Execute the graph's initializers, regardless of whether the session has been initialized.
+   *
+   * <p>This runs any ops that have been created with an init scope.
+   */
+  public synchronized void forceInitialize() {
+    if (!graph.hasInitializers()) {
+      hasInitialized = true;
+      return;
+    }
+
+    List<Operation> initializers = graph.initializers();
+    if (!initializers.isEmpty()) {
+      Runner runner = runner();
+      initializers.forEach(runner::addTarget);
+      runner.runNoInit();
+    }
+    hasInitialized = true;
+  }
+
   /** Create a session and initialize it. */
   public static Session initialized(Graph graph) {
     Session s = new Session(graph);

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

@@ -323,11 +323,9 @@ public void pythonTfFunction() {
   private static Signature buildGraphWithVariables(Ops tf, Shape xShape) {
     Placeholder<TFloat32> x = tf.placeholder(TFloat32.class, Placeholder.shape(xShape));
     Variable<TFloat32> y =
-        tf.initScope().withName("variable")
-            .variable(
-                tf
-                    .random
-                    .randomUniform(tf.constant(xShape), TFloat32.class));
+        tf.initScope()
+            .withName("variable")
+            .variable(tf.random.randomUniform(tf.constant(xShape), TFloat32.class));
     ReduceSum<TFloat32> z = tf.reduceSum(tf.math.add(x, y), tf.array(0, 1));
     return Signature.builder().input("input", x).output("reducedSum", z).build();
   }