1 files changed, 139 insertions, 0 deletions
diff --git a/processor/src/main/java/com/google/android/enterprise/connectedapps/processor/containers/FutureWrapper.java b/processor/src/main/java/com/google/android/enterprise/connectedapps/processor/containers/FutureWrapper.java
new file mode 100644
index 0000000..5208e7c
--- /dev/null
+++ b/processor/src/main/java/com/google/android/enterprise/connectedapps/processor/containers/FutureWrapper.java
@@ -0,0 +1,139 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * 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
+ *
+ *   https://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 com.google.android.enterprise.connectedapps.processor.containers;
+
+import com.google.android.enterprise.connectedapps.annotations.CustomFutureWrapper;
+import com.google.auto.value.AutoValue;
+import com.squareup.javapoet.ClassName;
+import java.util.ArrayList;
+import java.util.Collection;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.type.TypeMirror;
+import javax.lang.model.util.Elements;
+import javax.lang.model.util.Types;
+
+/** Information about future wrapper. */
+@AutoValue
+public abstract class FutureWrapper {
+
+  /** The type of the Wrapper. This controls how supporting code is generated. */
+  public enum WrapperType {
+    DEFAULT, // Copied from a resource
+    CUSTOM // Included in classpath
+  }
+
+  public static final String FUTURE_WRAPPER_PACKAGE =
+      "com.google.android.enterprise.connectedapps.futurewrappers";
+
+  public abstract TypeMirror wrappedType();
+
+  public abstract ClassName defaultWrapperClassName();
+
+  public abstract ClassName wrapperClassName();
+
+  public abstract WrapperType wrapperType();
+
+  private static FutureWrapper create(
+      TypeMirror wrappedType, ClassName defaultWrapperClassName, WrapperType wrapperType) {
+    return create(wrappedType, defaultWrapperClassName, defaultWrapperClassName, wrapperType);
+  }
+
+  public static FutureWrapper create(
+      TypeMirror wrappedType,
+      ClassName defaultWrapperClassName,
+      ClassName wrapperClassName,
+      WrapperType wrapperType) {
+    return new AutoValue_FutureWrapper(
+        wrappedType, defaultWrapperClassName, wrapperClassName, wrapperType);
+  }
+
+  public static Collection<FutureWrapper> createGlobalFutureWrappers(Elements elements) {
+    Collection<FutureWrapper> wrappers = new ArrayList<>();
+
+    addDefaultFutureWrappers(elements, wrappers);
+
+    return wrappers;
+  }
+
+  private static void addDefaultFutureWrappers(
+      Elements elements, Collection<FutureWrapper> wrappers) {
+    tryAddWrapper(
+        elements,
+        wrappers,
+        "com.google.common.util.concurrent.ListenableFuture",
+        ClassName.get(FUTURE_WRAPPER_PACKAGE, "ListenableFutureWrapper"),
+        WrapperType.DEFAULT);
+  }
+
+  public static Collection<FutureWrapper> createCustomFutureWrappers(
+      Types types, Elements elements, Collection<TypeElement> customFutureWrappers) {
+    Collection<FutureWrapper> wrappers = new ArrayList<>();
+
+    addCustomFutureWrappers(types, elements, wrappers, customFutureWrappers);
+
+    return wrappers;
+  }
+
+  private static void addCustomFutureWrappers(
+      Types types,
+      Elements elements,
+      Collection<FutureWrapper> wrappers,
+      Collection<TypeElement> customFutureWrappers) {
+    for (TypeElement customFutureWrapper : customFutureWrappers) {
+      addCustomFutureWrapper(types, elements, wrappers, customFutureWrapper);
+    }
+  }
+
+  private static void addCustomFutureWrapper(
+      Types types,
+      Elements elements,
+      Collection<FutureWrapper> wrappers,
+      TypeElement customFutureWrapper) {
+    CustomFutureWrapper customFutureWrapperAnnotation =
+        customFutureWrapper.getAnnotation(CustomFutureWrapper.class);
+
+    if (customFutureWrapperAnnotation == null) {
+      // This will be dealt with as part of early validation
+      return;
+    }
+
+    tryAddWrapper(
+        elements,
+        wrappers,
+        FutureWrapperAnnotationInfo.extractFromFutureWrapperAnnotation(
+                types, customFutureWrapperAnnotation)
+            .originalType()
+            .toString(),
+        ClassName.get(customFutureWrapper),
+        WrapperType.CUSTOM);
+  }
+
+  private static void tryAddWrapper(
+      Elements elements,
+      Collection<FutureWrapper> wrappers,
+      String typeQualifiedName,
+      ClassName wrapperClassName,
+      WrapperType wrapperType) {
+    TypeElement typeElement = elements.getTypeElement(typeQualifiedName);
+
+    if (typeElement == null) {
+      // The type isn't supported at compile-time - so won't be included in this app
+      return;
+    }
+
+    wrappers.add(FutureWrapper.create(typeElement.asType(), wrapperClassName, wrapperType));
+  }
+}