Fix jsonPointer key check

[wangxi761]

in this case , JsonPointer.isArrayIndex may cause NumberFormatException which jsonpointer is /xxx/119962931388000000000000000007

{
    "119962931388000000000000000007": "851905683938304000"
}

[wangxi761]

things aren't as simple as they seem，JsonPointer is a standalone container , It does not contain type information。

{
    "1": "851905683938304000"
}

jsonpointer is /1 , but we still can't say this is a array index or object key

to handle this, we need to add some additional information to it to determine whether this is the index of array or the key of the object?