yang/yang-parser-rfc7950/src/main/java/org/opendaylight/yangtools/yang/parser/rfc7950/stmt/AbstractEffectiveDocumentedNodeWithStatus.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.yangtools.yang.parser.rfc7950.stmt;
   9
  10 import com.google.common.collect.ImmutableList;
  11 import java.lang.invoke.MethodHandles;
  12 import java.lang.invoke.VarHandle;
  13 import java.util.ArrayList;
  14 import java.util.Collection;
  15 import java.util.List;
  16 import org.eclipse.jdt.annotation.NonNull;
  17 import org.opendaylight.yangtools.yang.model.api.DocumentedNode;
  18 import org.opendaylight.yangtools.yang.model.api.Status;
  19 import org.opendaylight.yangtools.yang.model.api.UnknownSchemaNode;
  20 import org.opendaylight.yangtools.yang.model.api.meta.DeclaredStatement;
  21 import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement;
  22 import org.opendaylight.yangtools.yang.model.api.stmt.StatusEffectiveStatement;
  23 import org.opendaylight.yangtools.yang.parser.spi.meta.StmtContext;
  24
  25 public abstract class AbstractEffectiveDocumentedNodeWithStatus<A, D extends DeclaredStatement<A>>
  26         extends AbstractEffectiveDocumentedNode<A, D> implements DocumentedNode.WithStatus {
  27     private static final VarHandle UNKNOWN_NODES;
  28
  29     static {
  30         try {
  31             UNKNOWN_NODES = MethodHandles.lookup().findVarHandle(AbstractEffectiveDocumentedNodeWithStatus.class,
  32                 "unknownNodes", ImmutableList.class);
  33         } catch (NoSuchFieldException | IllegalAccessException e) {
  34             throw new ExceptionInInitializerError(e);
  35         }
  36     }
  37
  38     private final @NonNull Status status;
  39
  40     @SuppressWarnings("unused")
  41     private volatile ImmutableList<UnknownSchemaNode> unknownNodes;
  42
  43     /**
  44      * Constructor.
  45      *
  46      * @param ctx
  47      *            context of statement.
  48      */
  49     protected AbstractEffectiveDocumentedNodeWithStatus(final StmtContext<A, D, ?> ctx) {
  50         super(ctx);
  51         status = findFirstEffectiveSubstatementArgument(StatusEffectiveStatement.class).orElse(Status.CURRENT);
  52     }
  53
  54     @Override
  55     public final Status getStatus() {
  56         return status;
  57     }
  58
  59     @Override
  60     public final Collection<? extends UnknownSchemaNode> getUnknownSchemaNodes() {
  61         final ImmutableList<UnknownSchemaNode> existing =
  62                 (ImmutableList<UnknownSchemaNode>) UNKNOWN_NODES.getAcquire(this);
  63         return existing != null ? existing : loadUnknownSchemaNodes();
  64     }
  65
  66     @SuppressWarnings("unchecked")
  67     private @NonNull ImmutableList<UnknownSchemaNode> loadUnknownSchemaNodes() {
  68         final List<UnknownSchemaNode> init = new ArrayList<>();
  69         for (EffectiveStatement<?, ?> stmt : effectiveSubstatements()) {
  70             if (stmt instanceof UnknownSchemaNode) {
  71                 init.add((UnknownSchemaNode) stmt);
  72             }
  73         }
  74
  75         final ImmutableList<UnknownSchemaNode> computed = ImmutableList.copyOf(init);
  76         final Object witness = UNKNOWN_NODES.compareAndExchangeRelease(this, null, computed);
  77         return witness == null ? computed : (ImmutableList<UnknownSchemaNode>) witness;
  78     }
  79 }