package cn.autoform.util.tool;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;

/**
 * 对象转换工具类
 * @ClassName: ObjectTools
 * @author [九鼎联合科技]
 * @date 2017年5月12日 下午1:00:24
 */
public class ObjectTool {
	
	/**
	 * 对象转byte
	 * @param obj
	 * @return
	 */
	public static byte[] objectToByte(Serializable obj) {
		if(Objects.isNull(obj)){
			return null;
		}
		byte[] bytes = null;

		try (
			ByteArrayOutputStream bo = new ByteArrayOutputStream();
			ObjectOutputStream oo = new ObjectOutputStream(bo)){
			oo.writeObject(obj);
			bytes = bo.toByteArray();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return bytes;
	}

	/**
	 * byte转对象
	 * @param bytes
	 * @param clazz
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public static <T> T byteToObject(byte[] bytes, Class<T> clazz) {
		if(Objects.isNull(bytes)) {
			return null;
		}
		T obj = null;
		ByteArrayInputStream bi = new ByteArrayInputStream(bytes);
		ObjectInputStream oi = null;
		try {
			oi = new ObjectInputStream(bi);
		} catch (IOException e) {
			return null;
		}
		try {
			obj = (T) oi.readObject();
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return obj;
	}

	/**
	 * 转前
	 * [Object,Object,Object,Object]
	 * 转后
	 * [Map,Map,Map,Map]
	 * @param objs
	 * @return
	 * @throws IllegalAccessException
	 */
	public static List<Map<String, Object>> toMapColl(Collection<?> objs) throws IllegalAccessException{
		List<Map<String, Object>> list = new ArrayList<>(objs.size());
		for (Object obj : objs) {
			list.add(toMapObj(obj));
		}
		return list;
	}
	
	/**
	 * 转前
	 * Object
	 * 转后
	 * Map
	 * @param obj
	 * @return
	 * @throws IllegalAccessException
	 */
	public static Map<String, Object> toMapObj(Object obj) throws IllegalAccessException{
		Class<?> clazz = obj.getClass();
		Map<String, Object> map = new HashMap<>();
		Field[] fields = clazz.getDeclaredFields();
		for (Field field : fields) {
			field.setAccessible(true);
			String fieldName = field.getName();
			Object fieldVal  = field.get(obj);
			if(fieldVal instanceof Collection){
				fieldVal = toMapColl((Collection<?>)fieldVal);
			}
			if(null != fieldVal)
				map.put(fieldName, fieldVal);
		}
		return map;
	}
}