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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.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.generatedAdapter;

final class StandardJsonAdapters {
    private StandardJsonAdapters() {
    }

    public static final JsonAdapter.Factory FACTORY = new JsonAdapter.Factory() {
        @Override
        public JsonAdapter create(
                Type type, Set annotations, Moshi moshi) {
            if (!annotations.isEmpty()) return null;
            if (type == boolean.class) return BOOLEAN_JSON_ADAPTER;
            if (type == byte.class) return BYTE_JSON_ADAPTER;
            if (type == char.class) return CHARACTER_JSON_ADAPTER;
            if (type == double.class) return DOUBLE_JSON_ADAPTER;
            if (type == float.class) return FLOAT_JSON_ADAPTER;
            if (type == int.class) return INTEGER_JSON_ADAPTER;
            if (type == long.class) return LONG_JSON_ADAPTER;
            if (type == short.class) return SHORT_JSON_ADAPTER;
            if (type == Boolean.class) return BOOLEAN_JSON_ADAPTER.nullSafe();
            if (type == Byte.class) return BYTE_JSON_ADAPTER.nullSafe();
            if (type == Character.class) return CHARACTER_JSON_ADAPTER.nullSafe();
            if (type == Double.class) return DOUBLE_JSON_ADAPTER.nullSafe();
            if (type == Float.class) return FLOAT_JSON_ADAPTER.nullSafe();
            if (type == Integer.class) return INTEGER_JSON_ADAPTER.nullSafe();
            if (type == Long.class) return LONG_JSON_ADAPTER.nullSafe();
            if (type == Short.class) return SHORT_JSON_ADAPTER.nullSafe();
            if (type == String.class) return STRING_JSON_ADAPTER.nullSafe();
            if (type == Object.class) return new ObjectJsonAdapter(moshi).nullSafe();

            Class rawType = Types.getRawType(type);

            @Nullable JsonAdapter generatedAdapter = generatedAdapter(moshi, type, rawType);
            if (generatedAdapter != null) {
                return generatedAdapter;
            }

            if (rawType.isEnum()) {
                //noinspection unchecked
                return new EnumJsonAdapter((Class) rawType).nullSafe();
            }
            return null;
        }
    };

    private static final String ERROR_FORMAT = "Expected %s but was %s at path %s";

    static int rangeCheckNextInt(JsonReader reader, String typeMessage, int min, int max)
            throws IOException {
        int value = reader.nextInt();
        if (value < min || value > max) {
            throw new JsonDataException(
                    String.format(ERROR_FORMAT, typeMessage, value, reader.getPath()));
        }
        return value;
    }

    static final JsonAdapter BOOLEAN_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Boolean fromJson(JsonReader reader) throws IOException {
            return reader.nextBoolean();
        }

        @Override
        public void toJson(JsonWriter writer, Boolean value) throws IOException {
            writer.value(value.booleanValue());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Boolean)";
        }
    };

    static final JsonAdapter BYTE_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Byte fromJson(JsonReader reader) throws IOException {
            return (byte) rangeCheckNextInt(reader, "a byte", Byte.MIN_VALUE, 0xff);
        }

        @Override
        public void toJson(JsonWriter writer, Byte value) throws IOException {
            writer.value(value.intValue() & 0xff);
        }

        @Override
        public String toString() {
            return "JsonAdapter(Byte)";
        }
    };

    static final JsonAdapter CHARACTER_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Character fromJson(JsonReader reader) throws IOException {
            String value = reader.nextString();
            if (value.length() > 1) {
                throw new JsonDataException(
                        String.format(ERROR_FORMAT, "a char", '"' + value + '"', reader.getPath()));
            }
            return value.charAt(0);
        }

        @Override
        public void toJson(JsonWriter writer, Character value) throws IOException {
            writer.value(value.toString());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Character)";
        }
    };

    static final JsonAdapter DOUBLE_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Double fromJson(JsonReader reader) throws IOException {
            return reader.nextDouble();
        }

        @Override
        public void toJson(JsonWriter writer, Double value) throws IOException {
            writer.value(value.doubleValue());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Double)";
        }
    };

    static final JsonAdapter FLOAT_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Float fromJson(JsonReader reader) throws IOException {
            float value = (float) reader.nextDouble();
            // Double check for infinity after float conversion; many doubles > Float.MAX
            if (!reader.isLenient() && Float.isInfinite(value)) {
                throw new JsonDataException("JSON forbids NaN and infinities: " + value
                        + " at path " + reader.getPath());
            }
            return value;
        }

        @Override
        public void toJson(JsonWriter writer, Float value) throws IOException {
            // Manual null pointer check for the float.class adapter.
            if (value == null) {
                throw new NullPointerException();
            }
            // Use the Number overload so we write out float precision instead of double precision.
            writer.value(value);
        }

        @Override
        public String toString() {
            return "JsonAdapter(Float)";
        }
    };

    static final JsonAdapter INTEGER_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Integer fromJson(JsonReader reader) throws IOException {
            return reader.nextInt();
        }

        @Override
        public void toJson(JsonWriter writer, Integer value) throws IOException {
            writer.value(value.intValue());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Integer)";
        }
    };

    static final JsonAdapter LONG_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Long fromJson(JsonReader reader) throws IOException {
            return reader.nextLong();
        }

        @Override
        public void toJson(JsonWriter writer, Long value) throws IOException {
            writer.value(value.longValue());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Long)";
        }
    };

    static final JsonAdapter SHORT_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public Short fromJson(JsonReader reader) throws IOException {
            return (short) rangeCheckNextInt(reader, "a short", Short.MIN_VALUE, Short.MAX_VALUE);
        }

        @Override
        public void toJson(JsonWriter writer, Short value) throws IOException {
            writer.value(value.intValue());
        }

        @Override
        public String toString() {
            return "JsonAdapter(Short)";
        }
    };

    static final JsonAdapter STRING_JSON_ADAPTER = new JsonAdapter() {
        @Override
        public String fromJson(JsonReader reader) throws IOException {
            return reader.nextString();
        }

        @Override
        public void toJson(JsonWriter writer, String value) throws IOException {
            writer.value(value);
        }

        @Override
        public String toString() {
            return "JsonAdapter(String)";
        }
    };

    static final class EnumJsonAdapter> extends JsonAdapter {
        private final Class enumType;
        private final String[] nameStrings;
        private final T[] constants;
        private final JsonReader.Options options;

        EnumJsonAdapter(Class enumType) {
            this.enumType = enumType;
            try {
                constants = enumType.getEnumConstants();
                nameStrings = new String[constants.length];
                for (int i = 0; i < constants.length; i++) {
                    T constant = constants[i];
                    Json annotation = enumType.getField(constant.name()).getAnnotation(Json.class);
                    String name = annotation != null ? annotation.name() : constant.name();
                    nameStrings[i] = name;
                }
                options = JsonReader.Options.of(nameStrings);
            } catch (NoSuchFieldException e) {
                throw new AssertionError("Missing field in " + enumType.getName() + ", " + e.getMessage());
            }
        }

        @Override
        public T fromJson(JsonReader reader) throws IOException {
            int index = reader.selectString(options);
            if (index != -1) return constants[index];

            // We can consume the string safely, we are terminating anyway.
            String path = reader.getPath();
            String name = reader.nextString();
            throw new JsonDataException("Expected one of "
                    + Arrays.asList(nameStrings) + " but was " + name + " at path " + path);
        }

        @Override
        public void toJson(JsonWriter writer, T value) throws IOException {
            writer.value(nameStrings[value.ordinal()]);
        }

        @Override
        public String toString() {
            return "JsonAdapter(" + enumType.getName() + ")";
        }
    }

    /**
     * This adapter is used when the declared type is {@code java.lang.Object}. Typically the runtime
     * type is something else, and when encoding JSON this delegates to the runtime type's adapter.
     * For decoding (where there is no runtime type to inspect), this uses maps and lists.
     *
     * 
This adapter needs a Moshi instance to look up the appropriate adapter for runtime types as
     * they are encountered.
     */
    static final class ObjectJsonAdapter extends JsonAdapter {
        private final Moshi moshi;
        private final JsonAdapter listJsonAdapter;
        private final JsonAdapter mapAdapter;
        private final JsonAdapter stringAdapter;
        private final JsonAdapter doubleAdapter;
        private final JsonAdapter booleanAdapter;

        ObjectJsonAdapter(Moshi moshi) {
            this.moshi = moshi;
            this.listJsonAdapter = moshi.adapter(List.class);
            this.mapAdapter = moshi.adapter(Map.class);
            this.stringAdapter = moshi.adapter(String.class);
            this.doubleAdapter = moshi.adapter(Double.class);
            this.booleanAdapter = moshi.adapter(Boolean.class);
        }

        @Override
        public Object fromJson(JsonReader reader) throws IOException {
            switch (reader.peek()) {
                case BEGIN_ARRAY:
                    return listJsonAdapter.fromJson(reader);

                case BEGIN_OBJECT:
                    return mapAdapter.fromJson(reader);

                case STRING:
                    return stringAdapter.fromJson(reader);

                case NUMBER:
                    return doubleAdapter.fromJson(reader);

                case BOOLEAN:
                    return booleanAdapter.fromJson(reader);

                case NULL:
                    return reader.nextNull();

                default:
                    throw new IllegalStateException(
                            "Expected a value but was " + reader.peek() + " at path " + reader.getPath());
            }
        }

        @Override
        public void toJson(JsonWriter writer, Object value) throws IOException {
            Class valueClass = value.getClass();
            if (valueClass == Object.class) {
                // Don't recurse infinitely when the runtime type is also Object.class.
                writer.beginObject();
                writer.endObject();
            } else {
                moshi.adapter(toJsonType(valueClass), Util.NO_ANNOTATIONS).toJson(writer, value);
            }
        }

        /**
         * Returns the type to look up a type adapter for when writing {@code value} to JSON. Without
         * this, attempts to emit standard types like `LinkedHashMap` would fail because Moshi doesn't
         * provide built-in adapters for implementation types. It knows how to write
         * those types, but lacks a mechanism to read them because it doesn't know how to find the
         * appropriate constructor.
         */
        private Class toJsonType(Class valueClass) {
            if (Map.class.isAssignableFrom(valueClass)) return Map.class;
            if (Collection.class.isAssignableFrom(valueClass)) return Collection.class;
            return valueClass;
        }

        @Override
        public String toString() {
            return "JsonAdapter(Object)";
        }
    }
}
    

    

    

            

    

            



    
    






    
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