efunbox-manage/manage-common/src/main/java/cn/efunbox/manage/common/utils/BeanUtil.java

package cn.efunbox.manage.common.utils;

import org.springframework.cglib.beans.BeanCopier;
import org.springframework.cglib.beans.BeanMap;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;


/**
 * 
 * 对象操作工具
 * 
 */
public class BeanUtil {

	/**
	 * 缓存BeanCopier对象，加快对象浅拷贝效率
	 */
	private static final Map<String, BeanCopier> BEAN_COPIERS = new ConcurrentHashMap<>();

	/**
	 * 缓存BeanMap对象，加快Map和javaBean对象的转化
	 */
	private static final Map<String, BeanMap> BEAN_MAP = new ConcurrentHashMap<>();

	private BeanUtil(){};
	
	/**
	 * 浅拷贝 只拷贝相同属性名和类型的
	 * 
	 * @param srcObj
	 *            被拷贝对象
	 * 
	 * @param destObj
	 *            拷贝对象
	 * 
	 */
	public static void copy(Object srcObj, Object destObj) {
		if (srcObj == null || destObj == null) {
			return;
		}
		String key = srcObj.getClass().getName() + destObj.getClass().getName();
		BeanCopier copier = null;
		if (BEAN_COPIERS.get(key)==null) {
			synchronized (BeanUtil.class) {
				if(BEAN_COPIERS.get(key)==null){
					copier = BeanCopier.create(srcObj.getClass(), destObj.getClass(), false);
					BEAN_COPIERS.put(key, copier);
				}
			}
		} else {
			copier = BEAN_COPIERS.get(key);
		}
		copier.copy(srcObj, destObj, null);
	}

	/**
	 * 对象转map
	 * @param obj
	 * @param fieldNames 需要存入的属性名 属性名之间以,分隔
	 * @param <T>
	 * @return
	 */
	public static <T> Map<String, Object> getMapByField(T obj, String fieldNames) {
		Map<String, Object> map = new HashMap<String, Object>();
		if (obj == null || fieldNames == null) {
			return map;
		}
		BeanMap beanMap = null;
		beanMap=getBeanMap(obj);
		for (String f : fieldNames.split(",")) {
			map.put(f, beanMap.get(f));
		}
		return map;
	}

	/**
	 * 对象转map
	 * @param obj
	 * @param removefieldNames 不需要存入的属性名 属性名之间以,分隔
	 * @param <T>
	 * @return
	 */
	public static <T> Map<String, Object> getMapByRemoveField(T obj, String removefieldNames) {
		Map<String, Object> map = new HashMap<String, Object>();
		if (obj == null) {
			return map;
		}
		BeanMap beanMap = null;
		beanMap=getBeanMap(obj);
		for (Object key : beanMap.keySet()) {
			map.put(key + "", beanMap.get(key));
		}
		if(removefieldNames!=null){
			for(String key:removefieldNames.split(",")){
				map.remove(key);
			}
		}
		return map;
	}

	/**
	 * 对象转map
	 *
	 * @param srcObj
	 * @return
	 */
	public static Map<String, Object> getMap(Object srcObj) {
		return getMapByRemoveField(srcObj, null);
	}

	/**
	 * map转对象
	 *
	 * @param map
	 * @param obj
	 *            需要转换的空对象
	 *
	 * @return
	 */
	public static <T> T mapToObj(Map<String, Object> map, T obj) {
		if (obj == null || map == null) {
			return null;
		}
		BeanMap beanMap = null;
		beanMap=getBeanMap(obj);
		beanMap.putAll(map);
		return obj;
	}

	/**
	 * 对象集合转map集合
	 *
	 * @param objList
	 * @return
	 */
	public static <T> List<Map<String, Object>> objectsToMaps(List<T> objList) {
		List<Map<String, Object>> list = new ArrayList<>();
		if (objList != null && objList.size() > 0) {
			Map<String, Object> map = null;
			T obj = null;
			for (int i = 0, size = objList.size(); i < size; i++) {
				obj = objList.get(i);
				map = getMap(obj);
				list.add(map);
			}
		}
		return list;
	}

	/**
	 * map集合转对象集合
	 *
	 * @param maps
	 * @param clazz
	 *            转换的对象class
	 * @return
	 */
	public static <T> List<T> mapsToObjects(List<Map<String, Object>> maps, Class<T> clazz) {
		List<T> list = new ArrayList<>();
		if (maps != null && maps.size() > 0) {
			Map<String, Object> map = null;
			T bean = null;
			try {
				for (int i = 0, size = maps.size(); i < size; i++) {
					map = maps.get(i);
					bean = clazz.newInstance();
					mapToObj(map, bean);
					list.add(bean);
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
		return list;
	}

	private static BeanMap getBeanMap(Object obj){
		BeanMap beanMap=null;
		String key=obj.getClass().getName();
		if (BEAN_MAP.get(key)==null) {
			synchronized (BeanUtil.class) {
				if(BEAN_MAP.get(key)==null){
					beanMap = BeanMap.create(obj);
					BEAN_MAP.put(key, beanMap);
				}
			}
		} else {
			beanMap =BEAN_MAP.get(key);
		}
		return beanMap;
	}

}