[Java/Reflect]使用反射机制获得一个对象的属性名和属性值

一个辅助对象,用于给属性排序

class KeyValue implements Comparable<KeyValue>{
    String key;
    Object value;

    @Override
    public int compareTo(KeyValue another) {
        return this.key.compareTo(another.key);
    }
}

两个函数:

   /**
     * get a series of object's properties
     * @param obj
     * @return
     */
    private String getObjectProperties(Object obj) {
        Field[] fields=obj.getClass().getDeclaredFields();
        //String[] fieldNames=new String[fields.length];
        List<KeyValue> kvList=new ArrayList<KeyValue>(fields.length);

        for(int i=0;i<fields.length;i++){
            KeyValue kv=new KeyValue();
            kv.key=fields[i].getName();
            kv.value=getFieldValueByName(kv.key,obj);

            kvList.add(kv);
        } 

        Collections.sort(kvList);

        StringBuilder sb=new StringBuilder();
        int idx=0;
        for(KeyValue kv:kvList) {
            idx++;
            sb.append("#"+idx+","+kv.key+","+kv.value+"\n");
        }

        return sb.toString();
    }

    /**
     * get property value of a object
     * @param fieldName
     * @param o
     * @return
     */
    private static Object getFieldValueByName(String fieldName, Object o) {
        try {
            String firstLetter = fieldName.substring(0, 1).toUpperCase();
            String getter = "get" + firstLetter + fieldName.substring(1);
            Method method = o.getClass().getMethod(getter, new Class[] {});
            Object value = method.invoke(o, new Object[] {});
            return value;
        } catch (Exception e) {
            return null;
        }
    } 

调用效果:

#1,connectPointCode,10005
#2,connectPointDetailCode,1
#3,createdDatetime,2019-12-03 14:54:48.248
#4,createdUser,BatchUser
#5,deliveryDate,Tue Dec 03 14:54:48 JST 2019
#6,errorCount1,null
#7,errorCount2,null
#8,errorCount3,null
#9,interfaceCode,00001
#10,ioCount1,0
#11,ioCount2,null
#12,ioCount3,null
#13,ioStatus,1
#14,processCount,23
#15,updatedDatetime,2019-12-03 14:54:48.248
#16,updatedUser,BatchUser
#17,userDataParam01,AllocationReq_10005_20191127163829.csv
#18,userDataParam02,0
#19,userDataParam03,null
#20,userDataParam04,null
#21,userDataParam05,null
#22,userDataParam06,null
#23,userDataParam07,null
#24,userDataParam08,null
#25,userDataParam09,null
#26,userDataParam10,null

感谢:

https://blog.csdn.net/a1527238987/article/details/79121372