binding/mdsal-binding-dom-codec/src/main/java/org/opendaylight/mdsal/binding/dom/codec/impl/IdentityCodec.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.mdsal.binding.dom.codec.impl;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.base.Throwables;
  13 import com.google.common.cache.CacheBuilder;
  14 import com.google.common.cache.CacheLoader;
  15 import com.google.common.cache.LoadingCache;
  16 import java.lang.reflect.Field;
  17 import java.lang.reflect.Modifier;
  18 import java.util.concurrent.ExecutionException;
  19 import org.eclipse.jdt.annotation.NonNull;
  20 import org.opendaylight.mdsal.binding.dom.codec.api.BindingIdentityCodec;
  21 import org.opendaylight.mdsal.binding.runtime.api.BindingRuntimeContext;
  22 import org.opendaylight.mdsal.binding.spec.reflect.BindingReflections;
  23 import org.opendaylight.yangtools.yang.binding.BaseIdentity;
  24 import org.opendaylight.yangtools.yang.binding.contract.Naming;
  25 import org.opendaylight.yangtools.yang.common.QName;
  26
  27 final class IdentityCodec extends AbstractValueCodec<QName, BaseIdentity> implements BindingIdentityCodec {
  28     private final LoadingCache<@NonNull QName, @NonNull BaseIdentity> values = CacheBuilder.newBuilder()
  29         .build(new CacheLoader<>() {
  30             @Override
  31             public BaseIdentity load(final QName key) {
  32                 final var clazz = context.getIdentityClass(key);
  33                 final Field field;
  34                 try {
  35                     field = clazz.getField(Naming.VALUE_STATIC_FIELD_NAME);
  36                 } catch (NoSuchFieldException e) {
  37                     throw new LinkageError(clazz + " does not define required field " + Naming.VALUE_STATIC_FIELD_NAME,
  38                         e);
  39                 }
  40                 if (!Modifier.isStatic(field.getModifiers())) {
  41                     throw new LinkageError(field + " is not static");
  42                 }
  43
  44                 final Object value;
  45                 try {
  46                     value = clazz.cast(field.get(null));
  47                 } catch (IllegalAccessException e) {
  48                     throw new LinkageError(field + " is not accesssible", e);
  49                 }
  50                 if (value == null) {
  51                     throw new LinkageError(field + " is null");
  52                 }
  53                 try {
  54                     return clazz.cast(value);
  55                 } catch (ClassCastException e) {
  56                     throw new LinkageError(field + " value " + value + " has illegal type", e);
  57                 }
  58             }
  59         });
  60
  61     private final BindingRuntimeContext context;
  62
  63     IdentityCodec(final BindingRuntimeContext context) {
  64         this.context = requireNonNull(context);
  65     }
  66
  67     @Override
  68     protected BaseIdentity deserializeImpl(final QName input) {
  69         return toBinding(input);
  70     }
  71
  72     @Override
  73     protected QName serializeImpl(final BaseIdentity input) {
  74         return fromBinding(input);
  75     }
  76
  77     @Override
  78     @SuppressWarnings("unchecked")
  79     public <T extends BaseIdentity> T toBinding(final QName qname) {
  80         try {
  81             return (T) values.get(requireNonNull(qname));
  82         } catch (ExecutionException e) {
  83             Throwables.throwIfUnchecked(e.getCause());
  84             throw new IllegalStateException("Unexpected error translating " + qname, e);
  85         }
  86     }
  87
  88     @Override
  89     public QName fromBinding(final BaseIdentity bindingValue) {
  90         return BindingReflections.getQName(bindingValue);
  91     }
  92 }