[ONOS-6869] Move blocking DocumentTree to core primitives package and implement default methods for constructing blocking primitives

Change-Id: I9c227a690a120dba7d9d89c6c9178c8b357b52aa
diff --git a/core/api/src/main/java/org/onosproject/store/primitives/DefaultDocumentTree.java b/core/api/src/main/java/org/onosproject/store/primitives/DefaultDocumentTree.java
new file mode 100644
index 0000000..6f90df4
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/primitives/DefaultDocumentTree.java
@@ -0,0 +1,126 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * 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.onosproject.store.primitives;
+
+import com.google.common.base.Throwables;
+import org.onosproject.store.service.AsyncDocumentTree;
+import org.onosproject.store.service.ConsistentMapException;
+import org.onosproject.store.service.DocumentException;
+import org.onosproject.store.service.DocumentPath;
+import org.onosproject.store.service.DocumentTree;
+import org.onosproject.store.service.DocumentTreeListener;
+import org.onosproject.store.service.Synchronous;
+import org.onosproject.store.service.Versioned;
+
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * Synchronous wrapper for a {@link AsyncDocumentTree}. All operations are
+ * made by making the equivalent calls to a backing {@link AsyncDocumentTree}
+ * then blocking until the operations complete or timeout.
+ *
+ * @param <V> the type of the values
+ */
+public class DefaultDocumentTree<V> extends Synchronous<AsyncDocumentTree<V>> implements DocumentTree<V> {
+
+    private final AsyncDocumentTree<V> backingTree;
+    private final long operationTimeoutMillis;
+
+    public DefaultDocumentTree(AsyncDocumentTree<V> backingTree, long operationTimeoutMillis) {
+        super(backingTree);
+        this.backingTree = backingTree;
+        this.operationTimeoutMillis = operationTimeoutMillis;
+    }
+
+    @Override
+    public DocumentPath root() {
+        return backingTree.root();
+    }
+
+    @Override
+    public Map<String, Versioned<V>> getChildren(DocumentPath path) {
+        return complete(backingTree.getChildren(path));
+    }
+
+    @Override
+    public Versioned<V> get(DocumentPath path) {
+        return complete(backingTree.get(path));
+    }
+
+    @Override
+    public Versioned<V> set(DocumentPath path, V value) {
+        return complete(backingTree.set(path, value));
+    }
+
+    @Override
+    public boolean create(DocumentPath path, V value) {
+        return complete(backingTree.create(path, value));
+    }
+
+    @Override
+    public boolean createRecursive(DocumentPath path, V value) {
+        return complete(backingTree.createRecursive(path, value));
+    }
+
+    @Override
+    public boolean replace(DocumentPath path, V newValue, long version) {
+        return complete(backingTree.replace(path, newValue, version));
+    }
+
+    @Override
+    public boolean replace(DocumentPath path, V newValue, V currentValue) {
+        return complete(backingTree.replace(path, newValue, currentValue));
+    }
+
+    @Override
+    public Versioned<V> removeNode(DocumentPath path) {
+        return complete(backingTree.removeNode(path));
+    }
+
+    @Override
+    public void addListener(DocumentPath path, DocumentTreeListener<V> listener) {
+        complete(backingTree.addListener(path, listener));
+    }
+
+    @Override
+    public void removeListener(DocumentTreeListener<V> listener) {
+        complete(backingTree.removeListener(listener));
+    }
+
+    @Override
+    public void addListener(DocumentTreeListener<V> listener) {
+        complete(backingTree.addListener(listener));
+    }
+
+    private <T> T complete(CompletableFuture<T> future) {
+        try {
+            return future.get(operationTimeoutMillis, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new DocumentException.Interrupted();
+        } catch (TimeoutException e) {
+            throw new DocumentException.Timeout(name());
+        } catch (ExecutionException e) {
+            Throwables.propagateIfPossible(e.getCause());
+            throw new ConsistentMapException(e.getCause());
+        }
+    }
+}
diff --git a/core/api/src/main/java/org/onosproject/store/service/AsyncDocumentTree.java b/core/api/src/main/java/org/onosproject/store/service/AsyncDocumentTree.java
index 00bccda..04f015a 100644
--- a/core/api/src/main/java/org/onosproject/store/service/AsyncDocumentTree.java
+++ b/core/api/src/main/java/org/onosproject/store/service/AsyncDocumentTree.java
@@ -21,6 +21,8 @@
 
 import javax.annotation.concurrent.NotThreadSafe;
 
+import org.onosproject.store.primitives.DefaultDocumentTree;
+
 /**
  * A hierarchical <a href="https://en.wikipedia.org/wiki/Document_Object_Model">document tree</a> data structure.
  *
@@ -29,6 +31,11 @@
 @NotThreadSafe
 public interface AsyncDocumentTree<V> extends DistributedPrimitive {
 
+    @Override
+    default Type primitiveType() {
+        return Type.DOCUMENT_TREE;
+    }
+
     /**
      * Returns the {@link DocumentPath path} to root of the tree.
      *
@@ -148,4 +155,23 @@
     default CompletableFuture<Void> addListener(DocumentTreeListener<V> listener) {
         return addListener(root(), listener);
     }
+
+    /**
+     * Returns a new {@link DocumentTree} that is backed by this instance.
+     *
+     * @return new {@code DocumentTree} instance
+     */
+    default DocumentTree<V> asDocumentTree() {
+        return asDocumentTree(DistributedPrimitive.DEFAULT_OPERATION_TIMEOUT_MILLIS);
+    }
+
+    /**
+     * Returns a new {@link DocumentTree} that is backed by this instance.
+     *
+     * @param timeoutMillis timeout duration for the returned DocumentTree operations
+     * @return new {@code DocumentTree} instance
+     */
+    default DocumentTree<V> asDocumentTree(long timeoutMillis) {
+        return new DefaultDocumentTree<V>(this, timeoutMillis);
+    }
 }
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
index 0a4906e..90b9863 100644
--- a/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
@@ -21,6 +21,7 @@
 import org.apache.commons.collections.CollectionUtils;
 import org.apache.commons.lang.StringUtils;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
@@ -95,6 +96,39 @@
     }
 
     /**
+     * Creates a new {@code DocumentPath} from a list of path elements.
+     *
+     * @param elements path elements
+     * @return {@code DocumentPath} instance
+     */
+    public static DocumentPath from(String... elements) {
+        return from(Arrays.asList(elements));
+    }
+
+    /**
+     * Creates a new {@code DocumentPath} from a list of path elements.
+     *
+     * @param elements path elements
+     * @return {@code DocumentPath} instance
+     */
+    public static DocumentPath from(List<String> elements) {
+        return new DocumentPath(elements);
+    }
+
+    /**
+     * Creates a new {@code DocumentPath} from a list of path elements.
+     *
+     * @param elements path elements
+     * @param child child element
+     * @return {@code DocumentPath} instance
+     */
+    public static DocumentPath from(List<String> elements, String child) {
+        elements = new ArrayList<>(elements);
+        elements.add(child);
+        return from(elements);
+    }
+
+    /**
      * Returns the relative  path to the given node.
      *
      * @return relative  path to the given node.
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java b/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java
index e8e4746..ad6d405 100644
--- a/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentTree.java
@@ -26,7 +26,12 @@
  * @param <V> document tree value type
  */
 @NotThreadSafe
-public interface DocumentTree<V> {
+public interface DocumentTree<V> extends DistributedPrimitive {
+
+    @Override
+    default Type primitiveType() {
+        return Type.DOCUMENT_TREE;
+    }
 
     /**
      * Returns the {@link DocumentPath path} to root of the tree.
diff --git a/core/api/src/test/java/org/onosproject/store/service/DocumentPathTest.java b/core/api/src/test/java/org/onosproject/store/service/DocumentPathTest.java
index d267814..353cf30 100644
--- a/core/api/src/test/java/org/onosproject/store/service/DocumentPathTest.java
+++ b/core/api/src/test/java/org/onosproject/store/service/DocumentPathTest.java
@@ -37,6 +37,8 @@
         assertEquals(path.pathElements(), Arrays.asList("root", "a", "b"));
         assertEquals(path("root.a"), path.parent());
         assertEquals(path("b"), path.childPath());
+        path = DocumentPath.from("root", "a", "b");
+        assertEquals(path.pathElements(), Arrays.asList("root", "a", "b"));
     }
 
     @Test