2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
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
8 package org.opendaylight.yangtools.yang.model.repo.spi;
10 import com.google.common.annotations.Beta;
11 import com.google.common.base.Preconditions;
12 import com.google.common.collect.Interner;
13 import com.google.common.collect.Interners;
14 import java.util.Objects;
15 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
16 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
19 * A potential schema source. Instances of this class track the various
20 * representations of a schema source and the cost attached to obtaining
21 * the source from them.
24 public final class PotentialSchemaSource<T extends SchemaSourceRepresentation> {
26 * Each registered source has a cost associated with it. Since a particular
27 * representation can be acquired by various means, here are general constants
32 * The source is immediately available, via a lookup or similar.
36 * The source is available via a computation. For transformation-type
37 * computation, the cost of acquiring the cost needs to be added, too.
41 * The source is available by performing local IO, such that reading
46 * The source is available by performing remote IO, such as fetching
47 * from an HTTP server or similar.
51 private final int value;
53 Costs(final int value) {
60 * @return Const constant.
62 public int getValue() {
67 private static final Interner<PotentialSchemaSource<?>> INTERNER = Interners.newWeakInterner();
68 private final Class<? extends T> representation;
69 private final SourceIdentifier sourceIdentifier;
70 private final int cost;
72 private PotentialSchemaSource(final SourceIdentifier sourceIdentifier, final Class<? extends T> representation,
74 this.representation = Preconditions.checkNotNull(representation);
75 this.sourceIdentifier = Preconditions.checkNotNull(sourceIdentifier);
76 Preconditions.checkArgument(cost >= 0, "cost has to be non-negative");
80 public static <T extends SchemaSourceRepresentation> PotentialSchemaSource<T> create(
81 final SourceIdentifier sourceIdentifier, final Class<? extends T> representation, final int cost) {
82 return new PotentialSchemaSource<>(sourceIdentifier, representation, cost);
86 * Return a cached reference to an object equal to this object.
88 * @return A potentially shared reference, not guaranteed to be unique.
90 @SuppressWarnings("unchecked")
91 public PotentialSchemaSource<T> cachedReference() {
92 return (PotentialSchemaSource<T>) INTERNER.intern(this);
95 public SourceIdentifier getSourceIdentifier() {
96 return sourceIdentifier;
99 public Class<? extends T> getRepresentation() {
100 return representation;
103 public int getCost() {
108 public int hashCode() {
109 return Objects.hash(cost, representation, sourceIdentifier);
113 public boolean equals(final Object obj) {
117 if (!(obj instanceof PotentialSchemaSource)) {
120 final PotentialSchemaSource<?> other = (PotentialSchemaSource<?>) obj;
121 return cost == other.cost && representation.equals(other.representation)
122 && sourceIdentifier.equals(other.sourceIdentifier);