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/*
 * Copyright (C) 2014 Square, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.squareup.moshi;

import com.jn.langx.annotation.Nullable;
import com.jn.langx.util.collection.Collects;
import com.jn.langx.util.function.Consumer;
import com.squareup.moshi.easyjson.EasyJsonAdapterFactory;
import com.squareup.moshi.internal.Util;

import java.io.IOException;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.*;

import static com.squareup.moshi.internal.Util.*;

/**
 * Coordinates binding between JSON values and Java objects.
 */
public final class Moshi {
    static final List BUILT_IN_FACTORIES = new ArrayList(5);

    static {
        BUILT_IN_FACTORIES.add(new EasyJsonAdapterFactory(StandardJsonAdapters.FACTORY));
        BUILT_IN_FACTORIES.add(new EasyJsonAdapterFactory(CollectionJsonAdapter.FACTORY));
        BUILT_IN_FACTORIES.add(new EasyJsonAdapterFactory(MapJsonAdapter.FACTORY));
        BUILT_IN_FACTORIES.add(new EasyJsonAdapterFactory(ArrayJsonAdapter.FACTORY));
        BUILT_IN_FACTORIES.add(new EasyJsonAdapterFactory(ClassJsonAdapter.FACTORY));
    }

    private final List factories;
    private final ThreadLocal lookupChainThreadLocal = new ThreadLocal();
    private final Map> adapterCache = new LinkedHashMap>();

    Moshi(Builder builder) {
        final List factories = new ArrayList(builder.factories.size() + BUILT_IN_FACTORIES.size());
        Collects.forEach(builder.factories, new Consumer() {
            @Override
            public void accept(JsonAdapter.Factory factory) {
                if(factory instanceof EasyJsonAdapterFactory){
                    factories.add(factory);
                }else{
                    factories.add(new EasyJsonAdapterFactory(factory));
                }
            }
        });
        factories.addAll(BUILT_IN_FACTORIES);
        this.factories = Collections.unmodifiableList(factories);
    }

    /**
     * Returns a JSON adapter for {@code type}, creating it if necessary.
     */
    
    public  JsonAdapter adapter(Type type) {
        return adapter(type, Util.NO_ANNOTATIONS);
    }

    
    public  JsonAdapter adapter(Class type) {
        return adapter(type, Util.NO_ANNOTATIONS);
    }

    
    public  JsonAdapter adapter(Type type, Class annotationType) {
        if (annotationType == null) {
            throw new NullPointerException("annotationType == null");
        }
        return adapter(type,
                Collections.singleton(Types.createJsonQualifierImplementation(annotationType)));
    }

    
    public  JsonAdapter adapter(Type type, Class... annotationTypes) {
        if (annotationTypes.length == 1) {
            return adapter(type, annotationTypes[0]);
        }
        Set annotations = new LinkedHashSet(annotationTypes.length);
        for (Class annotationType : annotationTypes) {
            annotations.add(Types.createJsonQualifierImplementation(annotationType));
        }
        return adapter(type, Collections.unmodifiableSet(annotations));
    }

    
    public  JsonAdapter adapter(Type type, Set annotations) {
        return adapter(type, annotations, null);
    }

    /**
     * @param fieldName An optional field name associated with this type. The field name is used as a
     *                  hint for better adapter lookup error messages for nested structures.
     */
    
    @SuppressWarnings("unchecked") // Factories are required to return only matching JsonAdapters.
    public  JsonAdapter adapter(Type type, Set annotations,
                                      @Nullable String fieldName) {
        if (type == null) {
            throw new NullPointerException("type == null");
        }
        if (annotations == null) {
            throw new NullPointerException("annotations == null");
        }

        type = removeSubtypeWildcard(canonicalize(type));

        // If there's an equivalent adapter in the cache, we're done!
        Object cacheKey = cacheKey(type, annotations);
        synchronized (adapterCache) {
            JsonAdapter result = adapterCache.get(cacheKey);
            if (result != null) return (JsonAdapter) result;
        }

        LookupChain lookupChain = lookupChainThreadLocal.get();
        if (lookupChain == null) {
            lookupChain = new LookupChain();
            lookupChainThreadLocal.set(lookupChain);
        }

        boolean success = false;
        JsonAdapter adapterFromCall = lookupChain.push(type, fieldName, cacheKey);
        try {
            if (adapterFromCall != null) return adapterFromCall;

            // Ask each factory to create the JSON adapter.
            for (int i = 0, size = factories.size(); i < size; i++) {
                JsonAdapter result = (JsonAdapter) factories.get(i).create(type, annotations, this);
                if (result == null) continue;

                // Success! Notify the LookupChain so it is cached and can be used by re-entrant calls.
                lookupChain.adapterFound(result);
                success = true;
                return result;
            }

            throw new IllegalArgumentException(
                    "No JsonAdapter for " + typeAnnotatedWithAnnotations(type, annotations));
        } catch (IllegalArgumentException e) {
            throw lookupChain.exceptionWithLookupStack(e);
        } finally {
            lookupChain.pop(success);
        }
    }

    
    @SuppressWarnings("unchecked") // Factories are required to return only matching JsonAdapters.
    public  JsonAdapter nextAdapter(JsonAdapter.Factory skipPast, Type type,
                                          Set annotations) {
        if (annotations == null) {
            throw new NullPointerException("annotations == null");
        }

        type = removeSubtypeWildcard(canonicalize(type));

        int skipPastIndex = factories.indexOf(skipPast);
        if (skipPastIndex == -1) {
            throw new IllegalArgumentException("Unable to skip past unknown factory " + skipPast);
        }
        for (int i = skipPastIndex + 1, size = factories.size(); i < size; i++) {
            JsonAdapter result = (JsonAdapter) factories.get(i).create(type, annotations, this);
            if (result != null) return result;
        }
        throw new IllegalArgumentException("No next JsonAdapter for "
                + typeAnnotatedWithAnnotations(type, annotations));
    }

    /**
     * Returns a new builder containing all custom factories used by the current instance.
     */
    
    public Moshi.Builder newBuilder() {
        int fullSize = factories.size();
        int tailSize = BUILT_IN_FACTORIES.size();
        List customFactories = factories.subList(0, fullSize - tailSize);
        return new Builder().addAll(customFactories);
    }

    /**
     * Returns an opaque object that's equal if the type and annotations are equal.
     */
    private Object cacheKey(Type type, Set annotations) {
        if (annotations.isEmpty()) return type;
        return Arrays.asList(type, annotations);
    }

    public static final class Builder {
        final List factories = new ArrayList();

        public  Builder add(final Type type, final JsonAdapter jsonAdapter) {
            if (type == null) throw new IllegalArgumentException("type == null");
            if (jsonAdapter == null) throw new IllegalArgumentException("jsonAdapter == null");

            return add(new JsonAdapter.Factory() {
                @Override
                public @Nullable
                JsonAdapter create(
                        Type targetType, Set annotations, Moshi moshi) {
                    return annotations.isEmpty() && Util.typesMatch(type, targetType) ? jsonAdapter : null;
                }
            });
        }

        public  Builder add(final Type type, final Class annotation,
                               final JsonAdapter jsonAdapter) {
            if (type == null) throw new IllegalArgumentException("type == null");
            if (annotation == null) throw new IllegalArgumentException("annotation == null");
            if (jsonAdapter == null) throw new IllegalArgumentException("jsonAdapter == null");
            if (!annotation.isAnnotationPresent(JsonQualifier.class)) {
                throw new IllegalArgumentException(annotation + " does not have @JsonQualifier");
            }
            if (annotation.getDeclaredMethods().length > 0) {
                throw new IllegalArgumentException("Use JsonAdapter.Factory for annotations with elements");
            }

            return add(new JsonAdapter.Factory() {
                @Override
                public @Nullable
                JsonAdapter create(
                        Type targetType, Set annotations, Moshi moshi) {
                    if (Util.typesMatch(type, targetType)
                            && annotations.size() == 1
                            && Util.isAnnotationPresent(annotations, annotation)) {
                        return jsonAdapter;
                    }
                    return null;
                }
            });
        }

        public Builder add(JsonAdapter.Factory factory) {
            if (factory == null) throw new IllegalArgumentException("factory == null");
            factories.add(factory);
            return this;
        }

        public Builder add(Object adapter) {
            if (adapter == null) throw new IllegalArgumentException("adapter == null");
            return add(AdapterMethodsFactory.get(adapter));
        }

        Builder addAll(List factories) {
            this.factories.addAll(factories);
            return this;
        }

        
        public Moshi build() {
            return new Moshi(this);
        }
    }

    /**
     * A possibly-reentrant chain of lookups for JSON adapters.
     *
     * 

We keep track of the current stack of lookups: we may start by looking up the JSON adapter * for Employee, re-enter looking for the JSON adapter of HomeAddress, and re-enter again looking * up the JSON adapter of PostalCode. If any of these lookups fail we can provide a stack trace * with all of the lookups. * *

Sometimes a JSON adapter factory depends on its own product; either directly or indirectly. * To make this work, we offer a JSON adapter stub while the final adapter is being computed. * When it is ready, we wire the stub to that finished adapter. This is necessary in * self-referential object models, such as an {@code Employee} class that has a {@code * List} field for an organization's management hierarchy. * *

This class defers putting any JSON adapters in the cache until the topmost JSON adapter has * successfully been computed. That way we don't pollute the cache with incomplete stubs, or * adapters that may transitively depend on incomplete stubs. */ final class LookupChain { final List> callLookups = new ArrayList>(); final Deque> stack = new ArrayDeque>(); boolean exceptionAnnotated; /** * Returns a JSON adapter that was already created for this call, or null if this is the first * time in this call that the cache key has been requested in this call. This may return a * lookup that isn't yet ready if this lookup is reentrant. */ JsonAdapter push(Type type, @Nullable String fieldName, Object cacheKey) { // Try to find a lookup with the same key for the same call. for (int i = 0, size = callLookups.size(); i < size; i++) { Lookup lookup = callLookups.get(i); if (lookup.cacheKey.equals(cacheKey)) { Lookup hit = (Lookup) lookup; stack.add(hit); return hit.adapter != null ? hit.adapter : hit; } } // We might need to know about this cache key later in this call. Prepare for that. Lookup lookup = new Lookup(type, fieldName, cacheKey); callLookups.add(lookup); stack.add(lookup); return null; } /** * Sets the adapter result of the current lookup. */ void adapterFound(JsonAdapter result) { Lookup currentLookup = (Lookup) stack.getLast(); currentLookup.adapter = result; } /** * Completes the current lookup by removing a stack frame. * * @param success true if the adapter cache should be populated if this is the topmost lookup. */ void pop(boolean success) { stack.removeLast(); if (!stack.isEmpty()) { return; } lookupChainThreadLocal.remove(); if (success) { synchronized (adapterCache) { for (int i = 0, size = callLookups.size(); i < size; i++) { Lookup lookup = callLookups.get(i); JsonAdapter replaced = adapterCache.put(lookup.cacheKey, lookup.adapter); if (replaced != null) { ((Lookup) lookup).adapter = (JsonAdapter) replaced; adapterCache.put(lookup.cacheKey, replaced); } } } } } IllegalArgumentException exceptionWithLookupStack(IllegalArgumentException e) { // Don't add the lookup stack to more than one exception; the deepest is sufficient. if (exceptionAnnotated) { return e; } exceptionAnnotated = true; int size = stack.size(); if (size == 1 && stack.getFirst().fieldName == null) { return e; } StringBuilder errorMessageBuilder = new StringBuilder(e.getMessage()); for (Iterator> i = stack.descendingIterator(); i.hasNext(); ) { Lookup lookup = i.next(); errorMessageBuilder .append("\nfor ") .append(lookup.type); if (lookup.fieldName != null) { errorMessageBuilder .append(' ') .append(lookup.fieldName); } } return new IllegalArgumentException(errorMessageBuilder.toString(), e); } } /** * This class implements {@code JsonAdapter} so it can be used as a stub for re-entrant calls. */ static final class Lookup extends JsonAdapter { final Type type; final @Nullable String fieldName; final Object cacheKey; @Nullable JsonAdapter adapter; Lookup(Type type, @Nullable String fieldName, Object cacheKey) { this.type = type; this.fieldName = fieldName; this.cacheKey = cacheKey; } @Override public T fromJson(JsonReader reader) throws IOException { if (adapter == null) { throw new IllegalStateException("JsonAdapter isn't ready"); } return adapter.fromJson(reader); } @Override public void toJson(JsonWriter writer, T value) throws IOException { if (adapter == null) { throw new IllegalStateException("JsonAdapter isn't ready"); } adapter.toJson(writer, value); } @Override public String toString() { return adapter != null ? adapter.toString() : super.toString(); } } }