Map与JavaBean相互转换工具类

工具类：反射实现

使用范围：JavaBean类对象的属性不能是数组、List、Set、Map

public class MapBeanUtil {

    /**
     * JavaBean转Map
     * @param obj
     * @return
     */
    public static Map bean2Map(Object obj) {
        Map map = new LinkedHashMap();
        Class clazz = obj.getClass();

        for (Field field : clazz.getDeclaredFields()) {
            field.setAccessible(true);
            String fieldName = field.getName();
            Object value = null;
            try {
                value = field.get(obj);
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            }
            if (value == null){
                value = "";
            }
            map.put(fieldName, value);
        }
        return map;
    }

    /**
     * Map转JavaBean
     * @param clazz
     * @param map
     * @param 
     * @return
     */
    public static  T map2Bean(final Class clazz, final Map map) {
        if (map == null) {
            return null;
        }
        T res = null;
        try {
            res = clazz.getDeclaredConstructor().newInstance();
            //获取到所有属性，不包括继承的属性
            Field[] fields = clazz.getDeclaredFields();
            for (Field field : fields) {
                //获取字段的修饰符
                int mod = field.getModifiers();
                if (Modifier.isStatic(mod) || Modifier.isFinal(mod)) {
                    continue;
                }
                //设置对象的访问权限
                field.setAccessible(true);
                //根据属性名称去map获取value
                if(map.containsKey(field.getName())) {
                    //给对象赋值
                    field.set(res, map.get(field.getName()));
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return res;
    }

    public static void main(String[] args) throws Exception {
        HashMap map = new HashMap();
        map.put("id", 1001);
        map.put("username", "zhangsan");
        map.put("password", "123456");
        map.put("nickname", "张三");
        map.put("email", "369950806@qq.com");
        map.put("gender", true);
        map.put("birth", LocalDate.now());
        map.put("avatar", "/aa/bb/ab.jpg");
        map.put("role", "VIP");
        map.put("status", (byte) 1);
        map.put("salt", "ldfkasjghweoiq324");
        map.put("createTime", LocalDateTime.now());
        map.put("updateTime", LocalDateTime.now());

        User user = map2Bean(User.class, map);
        System.out.println(user);

        Map res = bean2Map(user);
        System.out.println(map);
    }
}

User类的代码：

public class User {
    private Integer id;
    private String username;
    private String password;
    private String nickname;
    private String email;
    private Boolean gender;
    private LocalDate birth;
    private String avatar;
    private String role;
    private Byte status;
    private String salt;
    private LocalDateTime createTime;
    private LocalDateTime updateTime;
}

工具类：反省实现

public class MapBeanTransUtil {
    public static  T map2Bean(Map map, Class clazz) throws IntrospectionException, IllegalAccessException, InvocationTargetException, NoSuchMethodException, InstantiationException {
        T obj = clazz.getDeclaredConstructor().newInstance();
        BeanInfo beanInfo = Introspector.getBeanInfo(clazz, Object.class);
        PropertyDescriptor[] pds = beanInfo.getPropertyDescriptors();
        for (PropertyDescriptor pd : pds) {
            String field = pd.getName();
           // System.out.println(field);
            Method writeMethod = pd.getWriteMethod();
            writeMethod.invoke(obj, map.get(field));
        }
        return obj;
    }

    public static Map bean2Map(Object obj) throws IntrospectionException, InvocationTargetException, IllegalAccessException {
        Map map = new HashMap();
        //获取对象的字节码
        Class clazz = obj.getClass();
        BeanInfo beanInfo = Introspector.getBeanInfo(clazz, Object.class);
        PropertyDescriptor[] pds = beanInfo.getPropertyDescriptors();
        for (PropertyDescriptor pd : pds) {
            String field = pd.getName();
            // System.out.println(field);
            Method readMethod = pd.getReadMethod();
            Object value = readMethod.invoke(obj);
            // System.out.println(value);
            map.put(field,value);
        }

        return map;
    }
        public static void main(String[] args) throws Exception {
        //将Map转换成Java对象
        Map map= new HashMap();
        map.put("id",1001L);
        map.put("name","zhangsan");
        map.put("gender",true);
        map.put("email","369950806@qq.com");
        map.put("tel","13264494458");
        map.put("credits",88);
        map.put("status",3);

        //内省
        Class clazz = User.class;
        User user = MapBeanTransUtil.map2Bean(map, clazz);
        System.out.println(user);

        System.out.println("***");
        Map res = MapBeanTransUtil.bean2Map(user);
        res.forEach((k,v)-> System.out.println(k+" - "+v));
    }
}