For these JSONTable steps, use the Jackson API which is dependency managed by Maven $($as in step A$).$

K A public put method which takes a key parameter $($string$),$ then a list of fields parameter $($list of objects$).$

$1$ If the degree of the given row doesn$$t match the result of calling the degree method, throw an illegal argument exception.

$2$ Check if the given key is a property under the data node to determine a hit or a miss.

$3$ On a hit, remove the old row at the key under the data node, put the new row at the key under the data node, call flush,

and return the old list of fields.

$4$ On a miss, put the new row at the key under the data node, call flush, and return null.

L A public get method which takes a key parameter.

$1$ Check if the given key is a property under the data node to determine a hit or a miss.

$2$ On a hit, return the old list of fields at the key under the data node.

$3$ On a miss, return null.

M A public remove method which takes a key parameter.

$1$ Check if the given key is a property under the data node to determine a hit or a miss.

$2$ On a hit, remove the old row at the key under the data node, call flush, and return the old list of fields.

$3$ On a miss, return null.