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.mdsal.binding.dom.codec.impl;
10 import static com.google.common.base.Verify.verifyNotNull;
11 import static java.util.Objects.requireNonNull;
13 import com.google.common.base.Throwables;
14 import com.google.common.cache.CacheBuilder;
15 import com.google.common.cache.CacheLoader;
16 import com.google.common.cache.LoadingCache;
17 import java.lang.invoke.MethodHandle;
18 import java.lang.invoke.MethodHandles;
19 import java.lang.invoke.MethodType;
20 import java.util.concurrent.ExecutionException;
21 import org.eclipse.jdt.annotation.NonNull;
22 import org.opendaylight.yangtools.yang.binding.ScalarTypeObject;
23 import org.opendaylight.yangtools.yang.binding.contract.Naming;
26 * Derived YANG types are just immutable value holders for simple value
27 * types, which are same as in NormalizedNode model.
29 final class EncapsulatedValueCodec extends SchemaUnawareCodec {
30 private static final MethodType OBJ_METHOD = MethodType.methodType(Object.class, Object.class);
33 * Use identity comparison for keys and allow classes to be GCd themselves.
35 * Since codecs can (and typically do) hold a direct or indirect strong reference to the class, they need to be also
36 * accessed via reference. Using a weak reference could be problematic, because the codec would quite often be only
37 * weakly reachable. We therefore use a soft reference, whose implementation guidance is suitable to our use case:
39 * "Virtual machine implementations are, however, encouraged to bias against clearing recently-created or
40 * recently-used soft references."
42 @SuppressWarnings("rawtypes")
43 private static final LoadingCache<Class<? extends ScalarTypeObject>, @NonNull EncapsulatedValueCodec> CACHE =
44 CacheBuilder.newBuilder().weakKeys().softValues().build(new CacheLoader<>() {
46 public EncapsulatedValueCodec load(final Class<? extends ScalarTypeObject> key)
47 throws ReflectiveOperationException {
48 final var method = key.getMethod(Naming.SCALAR_TYPE_OBJECT_GET_VALUE_NAME);
49 final var lookup = MethodHandles.publicLookup();
50 final var retType = method.getReturnType();
51 return new EncapsulatedValueCodec(lookup.findConstructor(key,
52 MethodType.methodType(void.class, retType)).asType(OBJ_METHOD),
53 lookup.unreflect(method).asType(OBJ_METHOD), retType);
57 private final MethodHandle constructor;
58 private final MethodHandle getter;
59 private final Class<?> valueType;
61 private EncapsulatedValueCodec(final MethodHandle constructor, final MethodHandle getter,
62 final Class<?> valueType) {
63 this.constructor = requireNonNull(constructor);
64 this.getter = requireNonNull(getter);
65 this.valueType = requireNonNull(valueType);
68 static @NonNull EncapsulatedValueCodec of(final Class<?> typeClz) throws ExecutionException {
69 return CACHE.get(typeClz.asSubclass(ScalarTypeObject.class));
72 static @NonNull EncapsulatedValueCodec ofUnchecked(final Class<?> typeClz) {
73 return CACHE.getUnchecked(typeClz.asSubclass(ScalarTypeObject.class));
77 * Quick check if a value object has a chance to deserialize using {@link #deserialize(Object)}.
79 * @param value Value to be checked
80 * @return True if the value can be encapsulated
82 boolean canAcceptObject(final Object value) {
83 return valueType.isInstance(value);
87 @SuppressWarnings({ "null", "checkstyle:illegalCatch" })
88 protected Object deserializeImpl(final Object input) {
90 return constructor.invokeExact(input);
91 } catch (Throwable e) {
92 Throwables.throwIfUnchecked(e);
93 throw new IllegalStateException(e);
98 @SuppressWarnings("checkstyle:illegalCatch")
99 protected Object serializeImpl(final Object input) {
101 return verifyNotNull(getter.invokeExact(input));
102 } catch (Throwable e) {
103 Throwables.throwIfUnchecked(e);
104 throw new IllegalStateException(e);