map和实体类互转的代码示例

# 1. 实体转Map

public class Test {
    public static void main(String[] args) {
        long s1 = System.currentTimeMillis();
        Map<String, Object> dataMap = objectToMap(new User().setUser());
        long s2 = System.currentTimeMillis();
        System.out.println("花费时间毫秒："+(s2-s1));
        System.out.println(dataMap);
    }
 
    public static Map<String, Object> objectToMap(Object object){
        Map<String,Object> dataMap = new HashMap<>();
        Class<?> clazz = object.getClass();
        for (Field field : clazz.getDeclaredFields()) {
            try {
                field.setAccessible(true);
                dataMap.put(field.getName(),field.get(object));
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            }
        }
        return dataMap;
    }
}




# 2. Map转实体

public static  <T> T mapToEntity(Map<String, Object> map, Class<T> entity) {
        if (null == map){
            return null;
        }
        T t = null;
        try {
            t = entity.newInstance();
            for(Field field : entity.getDeclaredFields()) {
                if (map.containsKey(field.getName())) {
                    boolean flag = field.isAccessible();
                    field.setAccessible(true);
                    Object object = map.get(field.getName());
                    if (object!= null && field.getType().isAssignableFrom(object.getClass())) {
                        field.set(t, object);
                    }
                    field.setAccessible(flag);
                }
            }
            return t;
        } catch (InstantiationException e) {
            logger.error("convert error ", e);
        } catch (IllegalAccessException e) {
            logger.error("convert error ", e);
        }
        return t;
    }