File managing system

• US 8,856,139 B2
• Filed: 09/20/2001
• Issued: 10/07/2014
• Est. Priority Date: 09/21/2000
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Igakura, Tomohiro
• Primary Examiner(s): Chen, Susan
• Application Number:
  US09/960,548
• Publication Number:
  US 20020042796A1
• Time in Patent Office: 4,765 Days
• Field of Search: 714/2, 709/203, 712/236, 719/328, 707/640, 707/698, 715/205
• US Class Current: 707/747
• CPC Class Codes: G06F 16/10 File systems; File servers

Abstract

A correspondence table 0121 for recording the correspondence relationship of file titles, file IDs and managing IDs, hash tables 0122 for recording the correspondence relationships of hash values of files and managing IDs and a file memory 0123 for keeping managing IDs and files are provided. When registering files, a file with any registered same title file is managed as a separate file by giving a separate managing ID. File content comparison with registered files is done, and a file with any registered same content file is registered as single file even if it has been registered with a separate file ID. When calling out a file, the file to be called is specified by the combination of the file title and the file ID.

Claims

1. A file managing system for managing a file, comprising:

(a) a file input unit configured to receive a file to be registered, a file title to be registered, and a file ID to be registered;

(b) a file request input unit configured to receive a requested file title and a requested file ID of a requested file;

(c) a file memory unit including;

a correspondence table that stores a correspondence relation-among the file title, the file ID, and a managing ID; and

a hash table that stores a relationship between a hash value of the file and the managing ID which uniquely identifies the file;

(d) a computer data processor programmed to include;

(1) a correspondence table search unit configured to receive the requested file title and the requested file ID from the file request input unit, search the correspondence table, to determine the presence or absence of the managing ID, corresponding to the requested file title or the requested file ID;

(2) a file search unit configured to search for a file stored in the file memory unit based on the managing ID obtained by the correspondence table search unit;

(3) a file content comparison unit configured to receive the file to be registered from the file input unit, compare a content of the file to be registered with a content of the file stored in the file memory unit, to determine a presence or absence of a similar content, and when there is the similar content file stored in the file memory unit, outputting the similar content file'"'"'s managing ID;

(4) a correspondence table change unit configured to store the file title to be registered, the file ID to be registered, and the managing ID of the similar content file output by the file content comparison unit in the correspondence table when it is determined by the file content comparison unit that the similar content file exists, and when it is determined by the file content comparison unit that the similar content file is not stored in the file memory unit, storing the file title to be registered, the file ID to be registered, and a new managing ID generated by the file search unit in the correspondence table;

(5) a file registration and delete unit configured to, when the similar content file does not exist, store the new managing ID and the file to be registered in the file memory unit;

(6) a file output unit that receives the requested file corresponding to the requested file title and the requested file ID from the computer data processor, and sends the requested file to the file request input unit; and

(7) a hash table search unit configured to search the hash table with the hash value of the file to be registered, and a hash table change unit configured to store, the hash value of the file to be registered and the new managing ID into the hash table when the similar content file does not exist;

wherein the file content comparison unit is further configured to compare a content of the file corresponding to the managing ID matched by the hash table search unit with the content of the file to be registered.

2. The file managing system according to claim 1,

wherein

the hash table is provided for each file title;

the correspondence table search unit is further configured to search the correspondence table to determine existence of a file having a same file title as the file to be registered; and

when the file having the same file title is stored in the correspondence table, the hash table search unit searches the hash table corresponding to the file title using the hash value of the file to be registered as a key.

3. The file managing system according to claim 2, wherein only a single hash table is provided for all file titles.

4. A file managing system for managing a file, comprising:

(a) a file input unit configured to receive a file to be registered, a file title to be registered, and a file ID to be registered;

(b) a file request input unit configured to receive a requested file title and a requested file ID of a requested file;

(c) a file memory unit including a hash table that stores a hash value for the file along with a relationship between the hash value, the file title, the file ID, and a managing ID for uniquely specifying the file;

(d) a computer data processor programmed to include;

(1) a correspondence table search unit configured to receive the requested file title and the requested file ID from the file request input unit, search the correspondence table to determine the presence or absence of the managing ID corresponding to the requested file title or the requested file ID;

(2) a file search unit configured to search for a file stored in the file memory unit based on the managing ID obtained by the correspondence table search unit;

(3) a file content comparison unit configured to receive the file to be registered from the file input unit, compare a content of the file to be registered with a content of the file stored in the file memory unit to determine a presence or absence of a similar content file, and when there is the similar content file stored in the file memory unit, outputting the similar content file'"'"'s managing ID;

(5) a correspondence table change unit configured to store the file title to be registered, the file ID to be registered, and a new managing ID generated by the file search unit into the correspondence table, and after that, when the file content comparison unit determines that the similar content file exists, deleting the file title, the file ID, and the new managing ID of the file to be registered from the correspondence table and storing the file title, the file ID, and the managing ID of the similar content file output by the file content comparison unit into the correspondence table; and

(6) a file registration and delete unit configured to, when the file, the file title, and the file ID are input to the file input unit, store the new managing ID created by the file search unit and the file to be registered into the file memory unit, and when the file content comparison unit determines that the similar content file exists, delete the new managing ID and the file corresponding to the new managing ID; and

(7) a file output unit that receives the requested file corresponding to the requested file title and the requested file ID from the computer data processor, and sends the requested file to the file request input unit; and

(8) a hash table search unit configured to search the hash table with the hash value of the file to be registered, and a hash table change unit configured to store, the hash value of the file to be registered and the new managing ID into the hash table when the similar content file does not exist; and

wherein the file content comparison unit is further configured to compare a content of the file corresponding to the managing ID matched by the hash table search unit with the content of the file to be registered.

5. A file managing method for managing a file in a file managing system comprising a file input unit, a computer data processor, and a memory unit comprising a correspondence table, a hash table, and a file memory unit, the method comprising:

receiving a file to be registered, a file title, and a file ID;

searching, with a hash table search unit of the data processor, the hash table for a correspondence relation between a hash value of the file and a managing ID for uniquely specifying the file using a hash value of the file to be registered as a key;

when the managing ID is obtained as a result of the search of the hash table, a file content comparison unit of the computer data processor searches for a file corresponding to the managing ID in the file memory unit, retrieves the file, and compares a content of the retrieved file with a content of the file to be registered;

when a content of the retrieved file is equivalent to a content of the file to be registered, a correspondence table change unit of the computer data processor registers the file title to be registered, the file ID to be registered, and the managing ID of the retrieved file into the correspondence table, and

when the hash table search unit searches the hash table and no match is found or when there is no file having an equivalent content, a file search unit of the computer data processor generates a new managing ID, a file registration delete unit of the computer data processor registers the new managing ID and the file to be registered into the file memory unit;

a hash table change unit of the computer data processor registers the new managing ID into the hash table using the hash value of the file to be registered as the key; and

the correspondence table change unit registers the file title to be registered, the file ID to be registered, and the new managing ID into the correspondence table.

6. The file managing method according to claim 5, wherein the hash table is provided for each file title, the correspondence table search unit of the computer data processor searches the correspondence table to determine whether or not there is a same file title as the file title of the file to be registered, when the same file title is not registered in the correspondence table, the hash table search unit determines that there is no search result, whereas when the same file title is registered in the correspondence table, the hash table search unit searches the hash table corresponding to the file title using a hash value of the file to be registered as the key.

7. The file managing method according to claim 5, wherein only a single hash table is provided for all file titles.

8. A file managing method for managing a file in a file managing system comprising a file input unit, a computer data processor, and a memory unit comprising a correspondence table, a hash table, and a file memory unit, the method comprising:

receiving a file to be registered, a file title, and a file ID;

generating, by a file search unit of the computer data processor, a new managing ID that is different from any already-registered file managing ID;

registering, by a file registration delete unit of the computer data processor, the new managing ID and the file to be registered into the file memory unit;

registering, by a correspondence table change unit of the computer data processor, the file title and the file ID of the file to be registered, and the new managing ID into the correspondence table;

searching, by a hash table search unit of the computer data processor, the hash table for a correspondence relation between a hash value of a registered file and a registered managing ID that uniquely specifies the registered file using a hash value of the file to be registered as a key,

when the managing ID is obtained as a result of the search of the hash table, a file content comparison unit of the computer data processor searches for a file corresponding to the managing ID in the file memory unit, retrieves the file, and compares a content of the retrieved file with a content of the file to be registered,

when a content of the retrieved file is equivalent to a content of the file to be registered, the correspondence table change unit changes the new managing ID registered in the correspondence table to a managing ID of the retrieved file; and

the file registration delete unit deletes the new managing ID and the file to be registered from the file memory unit,

when the hash table search unit searches the hash table and no match is found or when there is no file having an equivalent content, a hash table change unit of the computer data processor registers the new managing ID into the hash table using the hash value of the file to be registered as the key.