lodsve.web.mvc.json.CodeableEnumDeserializer Maven / Gradle / Ivy

Go to download
/*
 * Copyright (C) 2018  Sun.Hao
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see .
 */

package lodsve.web.mvc.json;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import lodsve.core.bean.Codeable;
import lodsve.core.utils.EnumUtils;
import lodsve.core.utils.NumberUtils;
import lodsve.core.utils.StringUtils;
import lodsve.web.mvc.config.WebMvcConfiguration;
import org.springframework.util.ReflectionUtils;

import java.io.IOException;
import java.lang.reflect.Field;

/**
 * Jackson反序列化枚举时，将code或者枚举value变成枚举.

 * {@link WebMvcConfiguration#objectMapper()}
 *
 * @author sunhao([email protected])
 * @date 2016/11/3 下午2:56
 */
public class CodeableEnumDeserializer extends JsonDeserializer {
    @Override
    @SuppressWarnings("unchecked")
    public Enum deserialize(JsonParser p, DeserializationContext context) throws IOException {
        String value = p.getValueAsString();
        if (StringUtils.isBlank(value)) {
            return null;
        }

        Class clazz = getType(p);
        if (clazz == null) {
            return null;
        }

        if (!Codeable.class.isAssignableFrom(clazz)) {
            return getEnumByOrdinal(clazz, value);
        }

        // 优先根据codeable去获取
        Enum result = getEnumFromCodeable(clazz, value);
        if (null != result) {
            return result;
        }

        try {
            // 根据枚举名称
            result = EnumUtils.getEnumByName(clazz, value);
        } catch (Exception e) {
            // 根据Ordinal
            result = getEnumByOrdinal(clazz, value);
        }

        return result;
    }

    @Override
    public Class handledType() {
        return Enum.class;
    }

    @SuppressWarnings("unchecked")
    private > Class getType(JsonParser p) throws IOException {
        Object object = p.getCurrentValue();
        Class clazz = object.getClass();
        String fieldName = p.getCurrentName();

        Field field = ReflectionUtils.findField(clazz, fieldName);
        Class type = ((null != field) ? field.getType() : null);

        if (support(type)) {
            return (Class) type;
        }

        return null;
    }

    private boolean support(Class clazz) {
        return clazz != null && Enum.class.isAssignableFrom(clazz) && Enum.class.isAssignableFrom(clazz);
    }

    private Enum getEnumByOrdinal(Class clazz, String value) {
        if (!NumberUtils.isNumber(value)) {
            throw new IllegalArgumentException("This value " + value + " is not Enum's Ordinal!");
        }

        return EnumUtils.getEnumByOrdinal(clazz, Integer.valueOf(value));
    }

    private Enum getEnumFromCodeable(Class clazz, String value) {
        for (Enum em : clazz.getEnumConstants()) {
            Codeable codeable = (Codeable) em;

            if (codeable.getCode().equals(value)) {
                return em;
            }
        }

        return null;
    }
}