Server, method, and program

Abstract

A server according to one aspect of the present disclosure is communicably connected to at least one terminal, and comprises: a registration unit which, upon receiving a message from the terminal, registers the message in a database on the basis of a type of the user of the terminal in a group to which the user belongs; and an acquisition unit which, upon receiving a message acquisition request from the terminal, acquires a message from the database on the basis of the message acquisition request and the type of the user of the terminal in the group to which the user belongs, and sends the message to the terminal. Said type includes a first type indicating a user able to send a message addressed to all users in the group, and a second type indicating a user only permitted to send a message addressed to a user of the first type.

Description

Server, method and program

[0001] The present disclosure relates to a server, a method, and a program.

[0002] Communication tools with a group chat function have been known for some time (for example, see Non-Patent Document 1). The group chat function generally allows multiple users in a group to communicate with each other via chat.

[0003] Business chat elgana (NTT West Japan), Internet <URL: https: / / elgana.jp / >

[0004] However, the conventional technology assumes that symmetrical communication will be carried out among the users in a group, and is not capable of asymmetrical communication.

[0005] The present disclosure has been made in consideration of the above points, and aims to provide a technology that can realize asymmetric communication.

[0006] A server according to one aspect of the present disclosure is a server communicatively connected to one or more terminals, and has a registration unit that, when it receives a message from the terminal, registers the message in a database based on the type of user in a group to which the user of the terminal belongs, and an acquisition unit that, when it receives a message acquisition request from the terminal, acquires a message from the database based on the message acquisition request and the type of user in a group to which the user of the terminal belongs, and sends the message to the terminal, wherein the types include a first type representing a user who is capable of sending messages addressed to all users in the group, and a second type representing a user who is only permitted to send messages addressed to users of the first type.

[0007] Asymmetric communication can be achieved.

[0008] 1 is a diagram showing an example of a sending-side user group and a receiving-side user group in a certain group. FIG. 2 is a diagram showing an example of a UI of a sending-side user. FIG. 3 is a diagram showing an example of a UI of a receiving-side user. FIG. 4 is a diagram showing an example of a UI of another receiving-side user. FIG. 5 is a diagram showing an example of the overall configuration of a chat system according to the present embodiment. FIG. 6 is a diagram showing an example of a hardware configuration of a chat server according to the present embodiment. FIG. 7 is a diagram showing an example of a hardware configuration of a user terminal according to the present embodiment. FIG. 8 is a diagram showing an example of a functional configuration of a chat server and a user terminal according to the present embodiment. FIG. 9 is a diagram showing an example of user information of a certain group. FIG. 10 is a diagram showing an example of setting information of a certain group. FIG. 11 is a diagram showing an example of a posted message of a certain group. A flowchart showing an example of the operation of the chat system when a message is posted. A flowchart showing an example of a message registration process. A flowchart showing an example of a message registration process of a sending-side user. A flowchart showing an example of a message registration process of a receiving-side user. A flowchart showing an example of the operation of the chat system when acquiring and viewing posted messages. A flowchart showing an example of a posted message acquisition process. A flowchart showing an example of a posted message acquisition process of a sending-side user.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described in detail with reference to the accompanying drawings. In the following embodiment, a chat system 1 capable of realizing asymmetric communication will be described.

[0010] <Outline of Asymmetric Communication Realized by Chat System 1> Hereinafter, an outline of the asymmetric communication realized by the chat system 1 according to this embodiment will be described.

[0011] In the chat system 1 of this embodiment, for a group consisting of one or more users, each user constituting the group is further divided into two subgroups (user groups): a "sending user group" and a "receiving user group."

[0012] A sending user group is a group mainly made up of users who send chat messages (hereinafter simply referred to as "messages") to each user in the group. Hereinafter, users included in the sending user group will also be referred to as "sending users." Sending users can basically view (view) all messages (however, as will be described later, it is possible to prevent some messages from being viewed).

[0013] On the other hand, the receiving user group is a group of users who mainly view messages and send messages to the sending user. Hereinafter, users included in the receiving user group will also be referred to as "receiving users." The receiving user group can only view messages addressed to everyone or to themselves. Furthermore, receiving users cannot send messages to other receiving users, but can only send messages to the sending user.

[0014] If a team or department in an organization such as a company is considered a group, examples of sending users of the group include managers such as a team leader, sub-leader, and department manager, while examples of receiving users include members of the group and general employees.

[0015] An example of a sending user group and a receiving user group in a group named "Sales ABC Summary" is shown in Figure 1. In the example shown in Figure 1, the sending user group includes the leader "Taro" and the sub-leader "Hanako." On the other hand, the receiving user group includes the members "Asuke," "Bmi," and "Cemon."

[0016] At this time, the UI (user interface) on the user terminal used by the sending user "Taro" is shown in Figure 2. The UI 1100 shown in Figure 2 includes a message display field 1110 in which messages are displayed, and a message input field 1120 in which messages are created and posted (sent). The message display field 1110 of the UI 1100 shown in Figure 2 displays a message M1001 addressed to everyone from the sending user "Taro," a message M1002 addressed to "Taro" from the receiving user "Bumi," a message M1003 addressed to "Asuke" from the sending user "Hanako," and a message M1004 from the receiving user "Asuke" with no recipient specified. Note that "@all" indicates that the message is addressed to everyone in the group, and "@username" indicates that the message is addressed to that user name.

[0017] 3 also shows the UI on the user terminal used by the receiving user "Asuke." The UI 1200 shown in FIG. 3 similarly includes a message display field 1210 and a message input field 1220. The message display field 1210 of the UI 1200 shown in FIG. 3 displays a message M1001 addressed to everyone from the sending user "Taro," a message M1003 addressed to "Asuke" from the sending user "Hanako," and a message M1004 from the receiving user "Asuke" with no recipient specified. In this way, the receiving user "Asuke" can view messages addressed to everyone, messages addressed to himself, and messages he has posted.

[0018] 4 also shows the UI on the user terminal used by the receiving user "Bmi." The UI 1300 shown in FIG. 4 similarly includes a message display field 1310 and a message input field 1320. The message display field 1310 of the UI 1300 shown in FIG. 4 displays a message M1001 addressed to everyone from the sending user "Taro," and a message M1002 addressed to "Taro" from the receiving user "Bmi." In this way, the receiving user "Bmi" can view messages addressed to everyone, messages addressed to herself, and messages she has posted (sent).

[0019] As described above, in the chat system 1 according to this embodiment, a sending user is essentially free from restrictions on sending and viewing messages, while a receiving user is restricted from sending and viewing messages, enabling asymmetric communication between the sending user and the receiving user. That is, a receiving user can only send messages to the sending user and can only view messages addressed to everyone or to themselves and messages posted by themselves. This allows a sending user to send messages only to specific receiving users without other receiving users seeing them. This allows, for example, a sending user to effectively and efficiently perform tasks that require the sending user to collect responses from each receiving user and that require confidentiality from other receiving users (e.g., checking and correcting a work schedule).

[0020] <Example of Overall Configuration of Chat System 1> An example of the overall configuration of the chat system 1 according to this embodiment is shown in Fig. 5. As shown in Fig. 5, the chat system 1 according to this embodiment includes a chat server 10 and N user terminals 20-n (n = 1, 2, ..., N). The chat server 10 and each user terminal 20-n (n = 1, 2, ..., N) are communicatively connected via a communication network 30 including, for example, the Internet. Hereinafter, when each user terminal 20-n (n = 1, 2, ..., N) is referred to collectively without distinction, it will be referred to as the "user terminal 20."

[0021] The chat server 10 is a server that manages groups made up of a sending user group and a receiving user group, and manages messages posted by users (hereinafter also referred to as "posted messages"). The chat server 10 can be realized, for example, by a general-purpose server or a system made up of such servers.

[0022] The user terminal 20 is a terminal used by a user. A user can post messages and view posted messages using the user terminal 20. Hereinafter, at least some of the users who use the user terminal 20 will be users who will be group creators or administrators. Hereinafter, a user who will be a group creator or administrator will be referred to as a "group creator / administrator." The user terminal 20 can be realized, for example, by a smartphone, a tablet terminal, a wearable device, a PC (personal computer), or the like.

[0023] 5 is an example, and is not intended to be limiting. For example, the chat system 1 may include various devices and equipment other than the chat server 10 and the user terminals 20.

[0024] <Example of Hardware Configuration of Chat Server 10 and User Terminal 20> <Example of Hardware Configuration of Chat Server 10> An example of the hardware configuration of the chat server 10 according to this embodiment is shown in Fig. 6. As shown in Fig. 6, the chat server 10 according to this embodiment has an input device 11, a display device 12, an external I / F 13, a communication I / F 14, a RAM (Random Access Memory) 15, a ROM (Read Only Memory) 16, an auxiliary storage device 17, and a processor 18. Each of these pieces of hardware is connected to each other via a bus 19 so as to be able to communicate with each other.

[0025] The input device 11 is, for example, a keyboard, a mouse, physical buttons, etc. The display device 12 is, for example, a display, a display panel, etc. Note that the chat server 10 does not necessarily have to have at least one of the input device 11 and the display device 12, for example.

[0026] The external I / F 13 is an interface with an external device such as a recording medium 13 a. Examples of the recording medium 13 a include a CD (Compact Disc), a DVD (Digital Versatile Disk), an SD memory card (Secure Digital memory card), and a USB (Universal Serial Bus) memory card.

[0027] The communication I / F 14 is an interface for connecting to the communication network 30. The RAM 15 is a volatile semiconductor memory (storage device) that temporarily stores programs and data. The ROM 16 is a non-volatile semiconductor memory (storage device) that can store programs and data even when the power is turned off. The auxiliary storage device 17 is a non-volatile storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a flash memory. The processor 18 is an arithmetic device such as a CPU (Central Processing Unit).

[0028] 6 is an example and is not intended to be limiting. The chat server 10 may, for example, have multiple auxiliary storage devices 17 or multiple processors 18, may not have some of the hardware shown in the figure, or may have various types of hardware other than the hardware shown in the figure.

[0029] <<Example of Hardware Configuration of User Terminal 20>> An example of the hardware configuration of the user terminal 20 according to this embodiment is shown in Fig. 7. As shown in Fig. 7, the user terminal 20 according to this embodiment has a touch panel 21, an external I / F 22, a communication I / F 23, a memory device 24, and a processor 25. Each of these pieces of hardware is connected to each other via a bus 26 so as to be able to communicate with each other.

[0030] The touch panel 21 is an input / output device that combines a display device such as a liquid crystal panel with a pointing device. The external I / F 22 is an interface with an external device such as a recording medium 22a. Examples of the recording medium 22a include an SD memory card and a USB memory card.

[0031] The communication I / F 23 is an interface for connecting to the communication network 30. The memory device 24 is a storage device such as a RAM, a ROM, a HDD, an SSD, a flash memory, etc. The processor 25 is an arithmetic device such as a CPU, etc.

[0032] 7 is an example and is not intended to be limiting. The user terminal 20 may, for example, have multiple memory devices 24 or multiple processors 25, may not have some of the hardware shown in the figure, or may have various types of hardware other than the hardware shown in the figure.

[0033] <Example of Functional Configuration of Chat Server 10 and User Terminal 20> <Example of Functional Configuration of Chat Server 10> An example of the functional configuration of the chat server 10 according to this embodiment is shown in FIG. 8. As shown in FIG. 8, the chat server 10 according to this embodiment has a message registration processing unit 101 and a posted message acquisition processing unit 102. These units are realized, for example, by processing in which one or more programs installed in the chat server 10 are executed by the processor 18 or the like. The chat server 10 according to this embodiment also has a user information DB 103, a setting information DB 104, and a posted message DB 105. Each of these DBs (databases) is realized, for example, by a storage area of ​​the auxiliary storage device 17 or the like. However, at least some of these DBs may be realized by a storage area of ​​a storage device communicatively connected to the chat server 10.

[0034] When a message is posted by the user terminal 20, the message registration processing unit 101 executes processing to register the message in the posted message DB 105. At this time, the message registration processing unit 101 references the user information stored in the user information DB 103 and the setting information stored in the setting information DB 104, and notifies the user specified as the destination of the posted message, or notifies the user who posted the message of an error if the destination of the message is inappropriate, etc. Hereinafter, the user who posted the message will also be referred to as the "poster."

[0035] When the user terminal 20 acquires and displays (views) a posted message, the posted message acquisition processor 102 executes processing to acquire the corresponding posted message from the posted message DB 105. At this time, the posted message acquisition processor 102 acquires the corresponding posted message from the posted message DB 105 by referring to the user information stored in the user information DB 103 and the setting information stored in the setting information DB 104.

[0036] The user information DB 103 stores, for each group, user information of the users who belong to that group. Specific examples of user information will be described later. Note that the user information for each group is created and updated, for example, by the group creator / manager of that group.

[0037] The setting information DB 104 stores setting information for each group, for the sending user group and the receiving user group of that group. Hereinafter, the setting information for the sending user group will be referred to as "sending side setting information," and the setting information for the receiving user group will be referred to as "receiving side setting information." Specific examples of sending side setting information and receiving side setting information will be described later. The sending side setting information and receiving side setting information for each group are created and updated, for example, by the group creator / manager of that group.

[0038] The posted message DB 105 stores, for each group, messages posted by users belonging to that group (posted messages). Specific examples of posted messages will be described later.

[0039] Specific Example of User Information As an example, FIG. 9 shows user information for a user belonging to a group named "Sales ABC Summary." As shown in FIG. 9, each piece of user information includes the group name of the group to which the user corresponding to the user information belongs, the user name of the user, the user type of the user, and the role of the user. Here, the user type is information indicating whether the user is a "sender user" or a "receiver user." The user type "sender" indicates that the user is a sender user, and the user type "receiver" indicates that the user is a receiver user. The role is information that can be set arbitrarily, and, for example, information indicating the user's role in the group (e.g., leader, sub-leader, member, etc.) is set.

[0040] Specific Examples of Setting Information As an example, FIG. 10 shows the sender setting information and receiver setting information for a group named "Sales ABC Summary." As shown in FIG. 10, the sender setting information includes "Posting setting without designated address," "Notification setting for messages addressed to all," "Display setting without designated address," "Display setting for sending user," and the like. Here, the "Posting setting without designated address" in the sender setting information is setting information indicating whether or not a sending user is permitted to post messages without a designated address, and its value is set to "Allow" or "Notify." The "Notification setting for messages addressed to all" is setting information indicating whether or not a sending user is notified of the message posting when a message addressed to all is posted, and its value is set to "Notify" or "Not notify." The "Display setting without designated address" is setting information indicating whether or not a posted message without a designated address can be viewed (displayed) when a sending user views a posted message, and its value is set to "Display" or "Hide." The "Display setting for sending user" is setting information indicating whether or not a posted message addressed to another sending user can be viewed (displayed) when a sending user views a posted message, and its value is set to "All" or "Only addressed to self." 10, the receiver setting information includes a "posting setting without a designated destination" etc. Here, the "posting setting without a designated destination" in the receiver setting information is setting information indicating whether or not a receiver user is permitted to post a message without a designated destination, and the value is set to "permitted" or "not permitted."

[0041] Specific Examples of Posted Messages As an example, Figure 11 shows a message posted to a group named "Sales ABC Summary." As shown in Figure 11, a posted message includes a "group name" that indicates the group to which the message was posted, a "posting date and time" that indicates the date and time the message was posted, a "poster" that indicates the username of the user who posted the message, a "destination" that indicates the destination specified in the message, and "text" that indicates the content of the message. Note that the posted message posted on the date and time "2024 / 3 / 7 11:30" is a message posted by a receiving user without specifying a destination, and does not include a destination.

[0042] 11, the message content is text data, but the message content is not limited to text data. The message content may include, for example, audio, images (including icons), video (including moving icons), attached files, etc.

[0043] <<Example of Functional Configuration of User Terminal 20>> Fig. 8 shows an example of the functional configuration of the user terminal 20 according to this embodiment. As shown in Fig. 8, the user terminal 20 according to this embodiment has a UI processing unit 201. The UI processing unit 201 is realized, for example, by processing in which one or more programs installed in the user terminal 20 are executed by the processor 25 or the like.

[0044] The UI processing unit 201 displays a UI that allows the display of posted messages and the posting of messages on the touch panel 21 of the user terminal 20. When posting a message, the UI processing unit 201 also transmits the message to the chat server 10, and when displaying the posted messages, the UI processing unit 201 acquires the posted messages from the chat server 10.

[0045] <Example of Operation of Chat System 1 When Message is Posted> An example of operation of the chat system 1 when a message is posted will be described with reference to FIG.

[0046] The UI processing unit 201 of the user terminal 20 creates a message in response to a user's operation and transmits (posts) the message to the chat server 10 (step S101). Here, the user can create and post a message using the UI displayed on the touch panel 21. At this time, when creating a message, the user specifies the recipient of the message (for example, "@all" if the message is addressed to everyone, or "@username" using the user's username if the message is addressed to a specific user). However, the user can also post a message without specifying a recipient.

[0047] The message includes the group name, posting date and time, poster, recipient, and text. However, if no recipient is specified, the message does not include a recipient.

[0048] The message registration processing unit 101 of the chat server 10 receives the message sent in step S101 (step S102).

[0049] The message registration processing unit 101 of the chat server 10 executes a registration process for the message received in step S102 (step S103). When the message received in step S102 is registered as a posted message, the message registration processing unit 101 returns information indicating that the message has been registered to the user terminal 20.

[0050] When the message posted in step S101 above is registered as a posted message, the UI processing unit 201 of the user terminal 20 stores the posted message locally (e.g., in a storage area of ​​the memory device 24, etc.) (step S104).

[0051] Message Posting Process Details of the message registration process in step S103 in FIG. 12 will be described with reference to FIG.

[0052] 12. The message registration processing unit 101 determines whether the poster of the message received in step S102 is a sending user or a receiving user (step S201). That is, the message registration processing unit 101 uses the group name and poster included in the message and the user information stored in the user information DB 103 to determine whether the user is a sending user or a receiving user based on the user type of the user information including the group name and poster.

[0053] If it is determined in step S201 above that the poster is the sending-side user, the message registration processing unit 101 executes message registration processing for the sending-side user (step S202).

[0054] If it is determined in step S201 above that the poster is a receiving-side user, the message registration processing unit 101 executes message registration processing for the receiving-side user (step S203).

[0055] <Message Posting Process by Sending User> Details of the message registration process by the sending user in step S202 of FIG. 13 will be described with reference to FIG.

[0056] The message registration processing unit 101 determines whether or not a destination is specified in the message received in step S102 of FIG. 12 (that is, whether or not the message includes a destination) (step S301).

[0057] If it is determined in step S301 that a destination is specified in the message, the message registration processing unit 101 registers (stores) the message as a posted message in the posted message DB 105 (step S302).

[0058] The message registration processing unit 101 determines whether the address included in the message is addressed to everyone (for example, "@all") (step S303).

[0059] If it is not determined in step S303 above that the address included in the message is addressed to everyone (that is, if the message is addressed to a specific user (e.g., "@username")), the message registration processing unit 101 sends a notification indicating that a message addressed to that user has been posted to the user terminal 20 of the user specified as the address (step S304). Note that, since the poster is the sending user, a specific receiving user is generally specified as the address, but this is not limiting, and a specific sending user may also be specified as the address.

[0060] If it is determined in step S303 above that the address included in the message is addressed to everyone, the message registration processing unit 101 performs notification or non-notification processing in accordance with the "Notification setting for message addressed to everyone" included in the sending-side setting information corresponding to the group with the group name included in the message (step S305). That is, if the "Notification setting for message addressed to everyone" included in the sending-side setting information is set to "Notification," the message registration processing unit 101 sends a notification indicating that the message has been posted to the user terminals 20 of all sending users. On the other hand, if the "Notification setting for message addressed to everyone" included in the sending-side setting information is set to "Non-notification," the message registration processing unit 101 does nothing (that is, does not send a notification indicating that the message has been posted).

[0061] If it is determined in step S301 that a destination is not specified for the message (i.e., if a destination is not specified for the message), the message registration processing unit 101 determines whether the "Posting setting without destination specification" is "Allowed" or "Not Allowed" (step S306). That is, the message registration processing unit 101 determines whether the "Posting setting without destination specification" included in the sender setting information corresponding to the group whose group name is included in the message is set to "Allowed" or "Not Allowed."

[0062] If it is determined in step S306 that the "posting setting without designated addressee" is "allowed," the message registration processing unit 101 registers (stores) the message in the posted message DB 105 as a posted message addressed to all users (step S307). That is, the message registration processing unit 101, for example, addresses the message to all users, and then registers (stores) the message in the posted message DB 105 as a posted message.

[0063] As in step S305 above, the message registration processing unit 101 performs notification or non-notification processing in accordance with the "notification settings for messages addressed to everyone" included in the sender setting information corresponding to the group with the group name included in the message (step S308).

[0064] If it is determined in step S306 that the "posting setting without designated recipient" is "not permitted," the message registration processing unit 101 notifies the user terminal 20 of the message poster of an error (step S309). In this case, posting of a message without designated recipient is not permitted.

[0065] <Message Posting Process by Receiving-Side User> Details of the message registration process by the receiving-side user in step S203 of FIG. 13 will be described with reference to FIG.

[0066] The message registration processing unit 101 determines whether or not a destination is specified in the message received in step S102 of FIG. 12 (step S401).

[0067] If it is determined in step S401 above that a destination is specified for the message, the message registration processing unit 101 determines whether the sending user is specified as the destination of the message (step S402).

[0068] If it is determined in step S402 above that the sender user is specified as the destination of the message, the message registration processing unit 101 registers (stores) the message as a posted message in the posted message DB 105 (step S403).

[0069] The message registration processing unit 101 sends a notification to the user terminal 20 of the user (sender user) specified as the destination of the message, indicating that a message addressed to that user has been posted (step S404).

[0070] If it is determined in step S402 above that the sending user is not specified as the destination of the message (that is, if the receiving user is specified as the destination or if the destination is addressed to everyone), the message registration processing unit 101 notifies the user terminal 20 of the poster of the message of an error (step S405). This is because a receiving user is restricted from posting a message addressed to another receiving user or a message addressed to everyone.

[0071] If it is determined in step S401 above that a destination is not specified for the message (i.e., if a destination is not specified for the message), the message registration processing unit 101 determines whether the "posting setting without destination specification" is "permitted" or "prohibited" (step S406). That is, the message registration processing unit 101 determines whether the "posting setting without destination specification" included in the receiver setting information corresponding to the group whose group name is included in the message is set to "permitted" or "prohibited."

[0072] If it is determined in step S406 that the "posting setting without designated destination" is "allowed," the message registration processing unit 101 registers (stores) the message as a posted message in the posted message DB 105 (step S407). In this case, the message is stored in the posted message DB 105 as a posted message without designated destination (i.e., a posted message that does not include a destination).

[0073] If it is determined in step S406 that the "posting setting without designated recipient" is "not permitted," the message registration processing unit 101 notifies the user terminal 20 of the message poster of an error (step S408). In this case, posting of a message without designated recipient is not permitted.

[0074] <Example of Operation of Chat System 1 When Acquiring and Viewing Posted Messages> An example of operation of the chat system 1 when acquiring and viewing posted messages will be described with reference to FIG.

[0075] The UI processing unit 201 of the user terminal 20 sends a posted message acquisition request to the chat server 10 (step S501). The posted message acquisition request is a request or demand for acquiring a posted message to be displayed from the chat server 10. The posted message acquisition request includes the username of the user using the user terminal 20 and the group name of the group to which the posted message to be displayed was posted. The UI processing unit 201 may send the posted message acquisition request in response to displaying a UI that displays posted messages from groups to which the user belongs and allows the user to post messages to those groups, or may send the posted message acquisition request at predetermined time intervals while the UI is displayed. Alternatively, the UI processing unit 201 may send the posted message acquisition request in response to receiving a notification indicating that a message addressed to the user has been posted, for example.

[0076] The posted message acquisition processing unit 102 of the chat server 10 receives the posted message acquisition request sent in step S501 (step S502).

[0077] The posted message acquisition processing unit 102 of the chat server 10 executes a process of acquiring posted messages based on the user name and group name included in the posted message acquisition request received in step S502 (step S503). Note that in the posted message acquisition process, posted messages that can be viewed by the user with the user name are acquired from posted messages posted by other users in the group with the group name.

[0078] The posted message acquisition processing unit 102 of the chat server 10 transmits the posted message acquired in step S503 to the user terminal 20 that is the sender of the posted message acquisition request received in step S502 (step S504).

[0079] The UI processor 201 of the user terminal 20 receives the posted message sent in step S504 (step S505).

[0080] The UI processing unit 201 of the user terminal 20 displays on the UI the message posted by the user using the user terminal 20 and the message received in step S505 (step S506). Note that the message posted by the user is stored locally (e.g., in a storage area of ​​the memory device 24) on the user terminal 20. However, if the message posted by the user is not stored locally, the message posted by the user may be acquired from the chat server 10.

[0081] <Posted Message Acquisition Process> Details of the posted message acquisition process in step S503 in FIG. 16 will be described with reference to FIG.

[0082] The posted message acquisition processor 102 determines whether the user who made the request for acquiring a posted message received in step S502 of Fig. 16 is a sending user or a receiving user (step S601). That is, the posted message acquisition processor 102 uses the user name and group name included in the request for acquiring a posted message and the user information stored in the user information DB 103 to determine whether the user is a sending user or a receiving user based on the user type of the user information including the user name and group name.

[0083] If it is determined in step S601 above that the requesting user is the sending user, the posted message acquisition processing unit 102 executes processing to acquire the posted message of the sending user (step S602).

[0084] If it is determined in step S601 above that the requesting user is a receiving user, the posted message acquisition processor 102 acquires from the posted message DB 105 posted messages that are posted by the sending user and addressed to the sending user (i.e., addressed to the user that requested the posted message acquisition request) or to all users (step S603). That is, when the user name and group name included in the posted message acquisition request are the "target user name" and the "target group name," respectively, the posted message acquisition processor 102 acquires from the posted message DB 105 posted messages that have the group name of the target group name, in which the sending user's username is set as the poster, and in which the target user name or all users is set as the destination. As a result, on the user terminal 20 used by the receiving user, a UI (e.g., UI 1200 shown in FIG. 3 or UI 1300 shown in FIG. 4 ) is displayed that includes posted messages posted by the sending user addressed to the receiving user or all users, in addition to posted messages posted by the receiving user himself / herself.

[0085] <<Processing for Acquiring a Message Posted by a Sending User>> Details of the processing for acquiring a message posted by a sending user in step S602 of Fig. 17 will be described with reference to Fig. 18. Hereinafter, the user name and group name included in the request for acquiring a message posted received in step S502 of Fig. 16 will be referred to as the "target user name" and the "target group name", respectively.

[0086] The posted message acquisition processor 102 determines whether the "display setting without destination designation" included in the sender setting information corresponding to the target group name is "display" or "non-display" (step S701).

[0087] If it is determined in step S701 above that the "display setting without destination specified" is "hidden," the posted message acquisition processing unit 102 determines whether the "display setting for sending user" included in the sending setting information corresponding to the target group name is "everyone" or "only to myself" (step S702).

[0088] If it is determined in step S702 above that the "display setting of the sending user" is "addressed to self only," the posted message acquisition processor 102 acquires posted messages addressed to the sending user or to all users from the posted message DB 105 (step S703). That is, the posted message acquisition processor 102 acquires posted messages whose group name is the target group name and whose destination is set to the target user name or to all users from the posted message DB 105. In this case, each sending user can view posted messages addressed to the sending user or to all users, but cannot view posted messages addressed to other sending users.

[0089] If it is determined in step S702 above that the "display setting for the sending user" is "everyone," the posted message acquisition processor 102 acquires from the posted message DB 105 posted messages addressed to the user name of any sending user or to all users (step S704). That is, the posted message acquisition processor 102 acquires from the posted message DB 105 posted messages whose group name is the target group name and whose destination is the user name of any sending user belonging to the group with the target group name or to all users. In this case, each sending user can view posted messages addressed to other sending users in addition to posted messages addressed to themselves or to all users. The usernames of sending users belonging to the group with the target group name can be identified from the target group name using user information stored in the user information DB 103.

[0090] If it is determined in step S701 above that the "display setting without destination specified" is "display," the posted message acquisition processing unit 102 determines whether the "display setting for sending user" included in the sending setting information corresponding to the target group name is "everyone" or "only to myself" (step S705).

[0091] If it is determined in step S705 above that the "sending user's display setting" is "addressed to self only," the posted message acquisition processor 102 acquires posted messages addressed to the sending user or to all users, and posted messages for which no address is specified, from the posted message DB 105 (step S706). That is, the posted message acquisition processor 102 acquires posted messages for which the group name is the target group name and for which the target user name or all users is set as the address, and posted messages for which no address is specified, from the posted message DB 105. In this case, each sending user can view posted messages for which no address is specified, in addition to posted messages addressed to the sending user or to all users.

[0092] If it is determined in step S705 above that the "display setting for the sending user" is "everyone," the posted message acquisition processor 102 acquires all posted messages from the posted message DB 105 (step S707). That is, the posted message acquisition processor 102 acquires posted messages for groups with the target group name from the posted message DB 105. In this case, each sending user can view all posted messages (more precisely, all posted messages posted to the group with the target group name).

[0093] <Summary> As described above, the chat system 1 according to this embodiment further groups users in a group into a sending user group and a receiving user group, enabling asymmetric communication between the sending user and the receiving user. That is, the sending user is basically permitted to send messages addressed to everyone, while the receiving user is only permitted to send messages addressed to the sending user. Furthermore, the sending user is basically allowed to view all messages posted in the group, while the receiving user is restricted from viewing messages posted to other receiving users or messages posted by other receiving users. Therefore, by using the chat system 1 according to this embodiment, for example, a sending user can effectively and efficiently perform tasks that require the sending user to collect responses from each receiving user and that require the sending user to keep the communications confidential from other receiving users (e.g., checking and correcting a work schedule, etc.).

[0094] The present invention is not limited to the above-described specifically disclosed embodiments, and various modifications, changes, and combinations with known technologies are possible without departing from the scope of the claims.

[0095] REFERENCE SIGNS LIST 1 Chat system 10 Chat server 11 Input device 12 Display device 13 External I / F 13a Recording medium 14 Communication I / F 15 RAM 16 ROM 17 Auxiliary storage device 18 Processor 19 Bus 20 User terminal 21 Touch panel 22 External I / F 22a Recording medium 23 Communication I / F 24 Memory device 25 Processor 26 Bus 30 Communication network 101 Message registration processing unit 102 Posted message acquisition processing unit 103 User information DB 104 Setting information DB 105 Posted message DB 201 UI processing unit

Claims

1. A server communicatively connected to one or more terminals, comprising: a registration unit that, when receiving a message from the terminal, registers the message in a database based on the type of user in a group to which the user of the terminal belongs; and an acquisition unit that, when receiving a message retrieval request from the terminal, retrieves the message from the database based on the message retrieval request and the type of user in the group to which the user of the terminal belongs, and sends the message to the terminal, wherein the types include a first type representing a user who is allowed to send messages addressed to all users in the group, and a second type representing a user who is only allowed to send messages addressed to users of the first type.

2. The server of claim 1, wherein the second type of user is a user who is further permitted to send messages without specifying a destination.

3. A server as described in claim 1 or 2, wherein the acquisition unit acquires from the database, when the user type is the second type, messages sent by a user of the first type and addressed to the user or to everyone.

4. The server of claim 3, wherein, when the user type is the first type, the acquisition unit refers to pre-created setting information and acquires from the database messages addressed to the user or all users, messages addressed to the user, other users of the first type, or all users, messages addressed to the user, all users, or no address specified, or all messages sent from terminals of users in the group.

5. The server according to claim 1, wherein the registration unit, when the user type is the first type and the destination of the message is not specified, registers the message in the database as addressed to everyone.

6. A server as described in claim 1 or 2, wherein, when the user type is the second type, the registration unit notifies the terminal that sent the message of an error when it receives a message specifying an unauthorized destination.

7. A method in which a server communicatively connected to one or more terminals executes: a registration procedure, when receiving a message from the terminal, to register the message in a database based on the user's type in a group to which the user of the terminal belongs; and an acquisition procedure, when receiving a message acquisition request from the terminal, to acquire a message from the database based on the message acquisition request and the user's type in the group to which the user of the terminal belongs, and send the message to the terminal, wherein the types include a first type representing a user who is allowed to send messages addressed to all users in the group, and a second type representing a user who is only allowed to send messages addressed to users of the first type.

8. A program that causes a server that is communicatively connected to one or more terminals to execute the following steps: a registration procedure, when receiving a message from the terminal, registering the message in a database based on the user's type in a group to which the user of the terminal belongs; and an acquisition procedure, when receiving a message acquisition request from the terminal, retrieving a message from the database and sending it to the terminal based on the message acquisition request and the user's type in the group to which the user of the terminal belongs, wherein the types include a first type representing a user that is capable of sending messages addressed to all users in the group, and a second type representing a user that is only permitted to send messages addressed to users of the first type.

Images