【java】之3种方式实现Object和Map之间的转换

 利用commons.BeanUtils实现Obj和Map之间转换，这种是最简单，也是最经常用的

public static Object mapToObject(Map<String, Object> map, Class<?> beanClass)
            throws Exception {
        if (map == null)
            return null;
        Object obj = beanClass.newInstance();
        org.apache.commons.beanutils.BeanUtils.populate(obj, map);
        return obj;
    }

    public static Map<?, ?> objectToMap(Object obj) {
        if (obj == null) {
            return null;
        }
        return new org.apache.commons.beanutils.BeanMap(obj);
    }

利用java reflect完成Obj和Map之间的相互转换

        public  Map<String,Object> Obj2Map(Object obj) throws Exception{
            Map<String,Object> map=new HashMap<String, Object>();
            Field[] fields = obj.getClass().getDeclaredFields();
            for(Field field:fields){
                field.setAccessible(true);
                map.put(field.getName(), field.get(obj));
            }
            return map;
        }
        public Object map2Obj(Map<String,Object> map,Class<?> clz) throws Exception{
            Object obj = clz.newInstance();
            Field[] declaredFields = obj.getClass().getDeclaredFields();
            for(Field field:declaredFields){
                int mod = field.getModifiers(); 
                if(Modifier.isStatic(mod) || Modifier.isFinal(mod)){
                    continue;
                }
                field.setAccessible(true);
                field.set(obj, map.get(field.getName()));
            }
            return obj;
        }

利用Introspector完成Obj和Map之间的相互转换

public Map<String,Object> obj2Map(Object obj) throws Exception{
            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;
        }
        
        public Object map2Obj(Map<String,Object> map,Class<?> clz) throws Exception{
            if (map == null)   
                return null;    
            Object obj = clz.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;
        }