java中实现map与对象相互转换的几种实现

//map转java对象
public static Object mapToObject(Map<String, Object> map, Class<?> beanClass)
  throws Exception {
 if (map == null) {
  return null;
 }
 Object obj = beanClass.newInstance();
 BeanUtils.populate(obj, map);
 return obj;
 }
 
//java对象转map
public static Map<?, ?> objectToMap(Object obj) {
 if (obj == null)
  return null;
 return new BeanMap(obj);
 }

//map转java对象
public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {
    if (map == null)
      return null;
    Object obj = beanClass.newInstance();
    BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());
    PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
    for (PropertyDescriptor property : propertyDescriptors) {
      Method setter = property.getWriteMethod();
      if (setter != null) {
        setter.invoke(obj, map.get(property.getName()));
      }
    }
    return obj;
  }
 
//java对象转map
public static Map<String, Object> objectToMap(Object obj) throws Exception {
 if (obj == null) {
 return null;
 }
 Map<String, Object> map = new HashMap<String, Object>();
 BeanInfo beanInfo = Introspector.getBeanInfo(obj.getClass());
 PropertyDescriptor[] propertyDescriptors = beanInfo
  .getPropertyDescriptors();
 for (PropertyDescriptor property : propertyDescriptors) {
 String key = property.getName();
 if (key.compareToIgnoreCase("class") == 0) {
  continue;
 }
 Method getter = property.getReadMethod();
 Object value = getter != null ? getter.invoke(obj) : null;
 map.put(key, value);
 }
 return map;
}

//map转java对象
public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {
    if (map == null) {
      return null;
    }
    Object object = beanClass.newInstance();
    Field[] fields = beanClass.getDeclaredFields();
    for (Field field : fields) {
      int mod = field.getModifiers();
      if (Modifier.isFinal(mod) || Modifier.isStatic(mod)) {
        continue;
      }
      field.setAccessible(true);
      field.set(object, map.get(field.getName()));
    }
    return object;
  }
 
//java对象转map
public static Map<String, Object> objectToMap(Object obj) throws Exception {
 if (obj == null) {
 return null;
 }
 Map<String, Object> map = new HashMap<String, Object>();
 Field[] declaredFields = obj.getClass().getDeclaredFields();
 for (Field field : declaredFields) {
 field.setAccessible(true);
 map.put(field.getName(), field.get(obj));
 }
 return map;
}

//map转java对象
public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {
  Object object = beanClass.newInstance();
  BeanMap beanMap = BeanMap.create(object);
  beanMap.putAll(map);
  return object;
}
 
//java对象转map
public static Map<String, Object> objectToMap(Object obj) {
  Map<String, Object> map = Maps.newHashMap();
  if (obj != null) {
    BeanMap beanMap = BeanMap.create(obj);
    for (Object key : beanMap.keySet()) {
      map.put(key + "", beanMap.get(key));
    }
  }
  return map;
}

//map转java对象
public static Object mapToObject(Map<String, Object> map, Class<?> beanClass) throws Exception {
  String jsonStr = JSONObject.toJSONString(map);
  return JSONObject.parseObject(jsonStr, beanClass);
}
 
//java对象转map
public static Map<String, Object> objectToMap(Object obj) {
  String jsonStr = JSONObject.toJSONString(obj);
  return JSONObject.parseObject(jsonStr);
}