org.sprintapi.hyperdata.gson.HyperDataAdapterFactory.java Source code

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Here is the source code for org.sprintapi.hyperdata.gson.HyperDataAdapterFactory.java

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/*
 * Copyright 2013 the original author or authors.
 *
 *  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 org.sprintapi.hyperdata.gson;

import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.LinkedHashSet;
import java.util.Set;

import org.apache.commons.lang.WordUtils;
import org.sprintapi.hyperdata.HyperdataContainer;
import org.sprintapi.hyperdata.HyperMap;
import org.sprintapi.hyperdata.MetadataContainer;

import com.google.gson.FieldNamingStrategy;
import com.google.gson.Gson;
import com.google.gson.TypeAdapter;
import com.google.gson.TypeAdapterFactory;
import com.google.gson.internal.ConstructorConstructor;
import com.google.gson.internal.Excluder;
import com.google.gson.internal.ObjectConstructor;
import com.google.gson.internal.bind.ReflectiveTypeAdapterFactory;
import com.google.gson.reflect.TypeToken;

public class HyperDataAdapterFactory extends ReflectiveTypeAdapterFactory implements TypeAdapterFactory {

    ConstructorConstructor constructorConstructor;
    FieldNamingStrategy fieldNamingPolicy;
    Excluder excluder;

    public HyperDataAdapterFactory(ConstructorConstructor constructorConstructor,
            FieldNamingStrategy fieldNamingPolicy, Excluder excluder) {
        super(constructorConstructor, fieldNamingPolicy, excluder);
        this.constructorConstructor = constructorConstructor;
        this.fieldNamingPolicy = fieldNamingPolicy;
        this.excluder = excluder;
    }

    @SuppressWarnings("unchecked")
    @Override
    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {

        Class<? super T> raw = type.getRawType();

        if (!Object.class.isAssignableFrom(raw) || HyperMap.class.isAssignableFrom(raw)) {
            return null; // it's a primitive or HyperMap
        }

        if (!raw.isAnnotationPresent(HyperdataContainer.class)) {
            return null; // it's not hyperdata
        }

        MetadataAccess metadataAccess = new MetadataAccess();

        Set<String> profiles = new LinkedHashSet<String>();

        Class<?> c = raw;
        while (c != null) {
            if (c.getClass().equals(Object.class)) {
                break;
            }

            HyperdataContainer hdc = c.getAnnotation(HyperdataContainer.class);
            if ((hdc != null) && (hdc.profile().length > 0)) {
                profiles.addAll(Arrays.asList(hdc.profile()));
            }
            Class<?>[] interfaces = c.getInterfaces();
            if (interfaces != null) {
                for (Class<?> i : interfaces) {
                    hdc = i.getAnnotation(HyperdataContainer.class);
                    if ((hdc != null) && (hdc.profile().length > 0)) {
                        profiles.addAll(Arrays.asList(hdc.profile()));
                    }
                }
            }

            c = c.getSuperclass();
        }

        metadataAccess.profile = profiles.toArray(new String[0]);

        for (Method method : raw.getMethods()) {
            if (method.isAnnotationPresent(MetadataContainer.class)) {
                if (method.getName().startsWith("get")) {
                    metadataAccess.getter = method;
                    metadataAccess.fieldName = method.getName().substring(3);

                } else if (method.getName().startsWith("set")) {
                    metadataAccess.setter = method;
                    metadataAccess.fieldName = method.getName().substring(3);
                }
            }
        }

        if (metadataAccess.fieldName != null) {
            if (metadataAccess.getter == null) {
                for (Method method : raw.getMethods()) {
                    if (method.getName().equals("get" + metadataAccess.fieldName)) {
                        metadataAccess.getter = method;
                        break;
                    }
                }
            } else if (metadataAccess.setter == null) {
                for (Method method : raw.getMethods()) {
                    if (method.getName().equals("set" + metadataAccess.fieldName)) {
                        metadataAccess.setter = method;
                        break;
                    }
                }
            }
            metadataAccess.fieldName = WordUtils.uncapitalize(metadataAccess.fieldName);
        }

        ObjectConstructor<T> constructor = constructorConstructor.get(type);
        return (TypeAdapter<T>) new HyperDataTypeAdapter(metadataAccess, constructorConstructor,
                (ObjectConstructor<Object>) constructor, getBoundFields(gson, type, raw), gson, this);
    }

    protected class MetadataAccess {
        public String[] profile;
        public String fieldName;
        public Method getter;
        public Method setter;
    }
}