A private static writeInt method which takes a path parameter, then an integer parameter.

$1$ Use the Serializable API to write the given integer to the file at the given path using the default behavior.

$2$ This step E is the functional inverse of step F below.

F A private static readInt method which takes a path parameter and returns an integer.

$1$ Use the Serializable API to read the stored integer from the file at the given path using the default behavior.

$2$ Return the stored integer read from the file.

$3$ This step F is the functional inverse of step E above.

G In the Row record, modify the following features:

$1$ Mark that the record implements the Serializable interface, but don$$t implement any methods of that API.

$.$

I A private static readRow method which takes a path parameter and returns a row.

$1$ Use the Serializable API to read the stored row from the file at the given path using the default behavior.

$2$ Return the stored row read from the file.

$3$ This step I is the functional inverse of step H above.

J A private static deleteRow method which takes a path parameter.

$1$ Delete the file at the given path.

$2$ If the count of the list of files under the parent directory of the given path is now $0,$ delete the parent directory too.

K A private digestFunction method which takes a key parameter.

$1$ Define a salt which is a string literal containing your full name, then concatenate the salt with the given key.

$2$ Compute a digest from the salted key above using the MessageDigest algorithm SHA$-1($known to be compromised$).$

$3$ Use java.util.HexFormat to convert the digest bytes to a lowercase hexadecimal string of $40$ characters.

$4$ Return the hexadecimal string.

L A private pathOf method which takes a digest parameter $($hexadecimal string$).$

$1$ Find the $2-$character hexadecimal prefix and the $38-$character hexadecimal suffix of the digest.

$2$ Resolve the suffix file under the prefix directory under the data directory.

$3$ Return the resolved path, which is the data directory sub $2-$character prefix directory sub $38-$character suffix file.

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$2$ND QUARTER: FRAMEWORK, PUT, GET, REMOVE

M A public clear method.

$1$ Walk the data directory by streaming as follows:

i Skip the first path in the stream, which is itself being walked and shouldn$$t be deleted.

ii Sort the stream in reverse order, which streams from the lowest files to the highest directories.

iii For each path in the stream, delete the corresponding file or directory.

$2$ Call writeInt $0$ to the size file under the metadata directory.

$3$ Call writeInt $0$ to the fingerprint file under the metadata directory.

N Public methods for the following statistics and predicates:

$1$ The name method which returns the name of the table root, excluding the base directories $($without an extension$).$

$2$ The columns method which returns the lines $($list of strings$)$ read from the columns file under the metadata directory.

$3$ The degree method which returns the size of the list of columns which is returned by the columns method.

$4$ The size method which returns readInt from the size file under the metadata directory.

$5$ The hashCode method which returns readInt from the fingerprint file under the metadata directory.

$6$ Don$$t implement capacity or loadFactor, because this is a FileTable, not a DataTable.

$7$ The equals method which returns true if the parameter is any table with the same fingerprint $($as in previous modules$).$

O 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.

$2$ Find the path of the digest of the given key $($calling steps K and L in order$).$

$3$ Create a new row composed of the key parameter and the list of fields parameter.

$4$ Check if a file exists at the path of the digest to determine a hit or a miss.

$5$ On a hit, readRow from the path of the old row, writeRow to the path with the new row, writeInt to the fingerprint

path under the metadata directory to update it $($like in previous modules$),$ and return the old list of fields.

$6$ On a miss, writeRow to the path with the new row, writeInt to the size and fingerprint paths under the metadata

directory to update them $($like in previous modules$),$ and return null.

P A public get method which takes a key parameter.

$1$ Find the path of the digest of the key equal to the given object $($calling steps K and L in order$).$

$2$ Check if a file exists at the path of the digest to determine a hit or a miss.

$3$ On a hit, readRow from the path of the old row, and return the old list of fields.

$4$ On a miss, return null.

Q A public remove method which takes a key parameter.

$1$ Find the path of the digest of the key equal to the given object $($calling steps K and L in order$).$

$2$ Check if a file exists at the path of the digest to determine a hit or a miss.

$3$ On a hit, readRow from the path of the old row, deleteRow at the same path, writeInt to the size and fingerprint

paths under the metadata