1 files changed, 90 insertions, 0 deletions
diff --git a/netconf/restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/restconf/impl/BatchedExistenceCheck.java b/netconf/restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/restconf/impl/BatchedExistenceCheck.java
new file mode 100644
index 0000000..4efc6a8
--- /dev/null
+++ b/netconf/restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/restconf/impl/BatchedExistenceCheck.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2017 Pantheon Technologies, s.r.o. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.netconf.sal.restconf.impl;
+
+import com.google.common.util.concurrent.FutureCallback;
+import com.google.common.util.concurrent.MoreExecutors;
+import com.google.common.util.concurrent.SettableFuture;
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import java.util.AbstractMap.SimpleImmutableEntry;
+import java.util.Collection;
+import java.util.Map.Entry;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
+import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
+import org.opendaylight.mdsal.common.api.ReadFailedException;
+import org.opendaylight.mdsal.dom.api.DOMDataTreeReadOperations;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+
+final class BatchedExistenceCheck {
+    private static final AtomicIntegerFieldUpdater<BatchedExistenceCheck> UPDATER =
+            AtomicIntegerFieldUpdater.newUpdater(BatchedExistenceCheck.class, "outstanding");
+
+    private final SettableFuture<Entry<YangInstanceIdentifier, ReadFailedException>> future = SettableFuture.create();
+
+    @SuppressWarnings("unused")
+    private volatile int outstanding;
+
+    private BatchedExistenceCheck(final int total) {
+        this.outstanding = total;
+    }
+
+    static BatchedExistenceCheck start(final DOMDataTreeReadOperations readTx,
+            final LogicalDatastoreType datastore, final YangInstanceIdentifier parentPath,
+            final Collection<? extends NormalizedNode> children) {
+        final BatchedExistenceCheck ret = new BatchedExistenceCheck(children.size());
+        for (NormalizedNode child : children) {
+            final YangInstanceIdentifier path = parentPath.node(child.getIdentifier());
+            readTx.exists(datastore, path).addCallback(new FutureCallback<Boolean>() {
+                @Override
+                public void onSuccess(final Boolean result) {
+                    ret.complete(path, result);
+                }
+
+                @Override
+                @SuppressFBWarnings("BC_UNCONFIRMED_CAST_OF_RETURN_VALUE")
+                public void onFailure(final Throwable throwable) {
+                    final Exception e;
+                    if (throwable instanceof Exception) {
+                        e = (Exception) throwable;
+                    } else {
+                        e = new ExecutionException(throwable);
+                    }
+
+                    ret.complete(path, ReadFailedException.MAPPER.apply(e));
+                }
+            }, MoreExecutors.directExecutor());
+        }
+
+        return ret;
+    }
+
+    Entry<YangInstanceIdentifier, ReadFailedException> getFailure() throws InterruptedException {
+        try {
+            return future.get();
+        } catch (ExecutionException e) {
+            // This should never happen
+            throw new IllegalStateException(e);
+        }
+    }
+
+    private void complete(final YangInstanceIdentifier childPath, final boolean present) {
+        final int count = UPDATER.decrementAndGet(this);
+        if (present) {
+            future.set(new SimpleImmutableEntry<>(childPath, null));
+        } else if (count == 0) {
+            future.set(null);
+        }
+    }
+
+    private void complete(final YangInstanceIdentifier childPath, final ReadFailedException cause) {
+        UPDATER.decrementAndGet(this);
+        future.set(new SimpleImmutableEntry<>(childPath, cause));
+    }
+}