Abstract:
The system for software installation of the present invention comprises: a storage medium for storing a file to be installed; a difference detector for comparing the file in the storage medium with a file in a target, and detecting a difference therebetween; a file operation determination device for determining an operation for the file, based on the comparison by the difference detector; and an installer for performing installation, based on the determination made by the file operation determination device.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a system and method for software installation. 
     This application is based on Japanese Patent Application No. Hei 10-368188, the contents of which are incorporated herein by reference. 
     2. Description of the Related Art 
     A conventional system for software installation is disclosed in Japanese Patent Application, First Publication No. Hei 4-30218. Referring to FIG. 6, the conventional system for software installation  61  comprises a difference list output device  611 , a file operation controller  612 , and a storage medium  613 . The difference list output device outputs a list indicating a difference, based on a release number  622  of the product in a storage medium  621  in a computer  62  and on a product update history recorded in the storage medium  613 . Based on this list, the file operations for installation are performed. 
     This conventional technique has the following problems: 
     The first disadvantage is that the installation cannot be performed while maintaining the data updated by the user. The data updated by the user cannot be completely deleted, and the initial installation state cannot be recovered. The reason for this is that the file operations for installation do not depend on the difference between the files but are always determined based on the release number of the product in the computer and on the product update history recorded in the storage medium. 
     The second disadvantage is that a damaged file cannot be recovered. The reason for this is that the damaged file is excluded from the target because the file operations are determined based on the release number and the product update history. 
     BRIEF SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a system and method for software installation which can appropriately select file operations and target files. 
     In a first aspect of the present invention, the system for software installation comprises: a storage medium for storing a file to be installed; a difference detector for comparing the file in the storage medium with the file in a target, and detecting a difference therebetween; a file operation determination device for determining an operation for the file, based on the comparison by the difference detector; and an installer for performing an installation, based on the determination made by the file operation determination device. 
     In a second aspect of the present invention, the difference detector comprises a list output device for outputting a list describing a difference between the file in the storage medium and the file in the target. 
     In a third aspect of the present invention, the system for software installation further comprises a file operation course selector for selecting a file operation course, depending on the type of the difference. 
     In a fourth aspect of the present invention, the file operation course selector selects to perform no file operation when the file in the storage medium is identical to the file in the target, to copy the file from the storage medium to the target when the file in the storage medium is different from the file in the target, to copy the file from the storage medium to the target when the file in the storage medium is not stored in the target, and to delete the file from the target when the file is not stored in the storage medium but is stored in the target. 
     In a fifth aspect of the present invention, the file operation determination device determines prohibiting a file operation for a file containing a setting value for software and for a file containing user data. 
     In a sixth aspect of the present invention, the file operation determination device determines copying the file from the storage medium to the target only when the file in the storage medium is newer than the file in the target. 
     In a seventh aspect of the present invention, the software installation method comprises the steps of: recording a file for installation; comparing the recorded file with a file in a target and detecting a difference therebetween; determining an operation for the file, based on the detection; and performing installation, based on the determination. 
     According to the present invention, the installation becomes quick because the invention installs only the different software files. 
     Further, a damaged file in the target computer can be detected or recovered, because the invention compares the files in the target with the source files to thereby detect the differences. 
     The installation is achieved while maintaining files personally added by a user because the file operations are preset based on the differences. 
     The invention avoids overwriting the latest version file, because no file operation is performed when the file version in the computer is newer than the file in the installation system. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram showing the first embodiment of the present invention. 
     FIG. 2 is a flowchart showing the operation of the first embodiment. 
     FIG. 3 is a diagram showing an example of the operations of the first embodiment. 
     FIG. 4 is a flowchart showing the operation of the second embodiment of the present invention. 
     FIG. 5 is a diagram showing an example of the operations of the second embodiment. 
     FIG. 6 is a block diagram showing the conventional technique. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows the first embodiment of the present invention. The system for software installation of the first embodiment comprises a difference detector  111 , a file operation determination device  112 , an installer  113 , a storage medium  114 , and a file operation course selector  115 . The software installation system  11  is to install the software in a storage medium  121  in a computer  12 . 
     The difference detector  111  compares files, which are installed and stored in the storage medium  121  in the computer  12 , with files which are stored in the storage medium  114  in the software installation system  11 , and outputs the list describing the presence or absence of the files and the differences in content between the files. Based on the file content difference list, the file operation determination device  112  selects one of the operations of addition, replacement, and deletion for each file, and outputs a file operation list. According to the file operation list, the installer  113  copies files, which are not stored in the storage medium  121  in the computer  12  or which were updated, from the storage medium  114  in the software installation system  11  to the storage medium  121 , and deletes unnecessary files from the storage medium  121  in the computer  12 . The file operation course selector  115  selects a file operation course, depending on the types of differences between the files. 
     The operation of the embodiment will now be explained. The storage medium  114  in the software installation system  11  stores all software files to be installed. 
     The difference detector  111  finds the differences between the files, which are installed and stored in the storage medium  121  in the computer  12 , and the files which are stored in the storage medium  114  in the software installation system  11 , and outputs the list. The file difference list includes the following information, e.g., “the file is stored in the storage medium  121  but is not stored in the storage medium  114 ”, “the file is not stored in the storage medium  121  but is stored in the storage medium  114 ”, “the file in the storage medium  114  was updated and is newer than the corresponding file in the storage medium  121 ”, or “the file, which was updated and is newer than the file in the storage medium  114 , is stored in the storage medium  121 .” 
     The file operation course selector  115  selects a file operation course for the file operation determination device  112 , depending on the types of differences. Based on the file difference list, the file operation determination device  112  determines, e.g., copying the files from the storage medium  114  in the software installation system to the storage medium  121  in the computer  12 , and deleting the files from the storage medium  121 , and then outputs the file operation list. 
     According to the file operation list, the installer  113  copies the files from the storage medium  114  in the software installation system  11  to the storage medium  121  in the computer  12 , and deletes unnecessary files from the storage medium  121  in the computer  12 . 
     The operation of the embodiment will be explained in more detail with reference to the flowchart of FIG.  2 . The file operation course selector  115  determines which operation the file operation determination device  112  is to determine, depending on the types of the differences in file content between the storage medium  121  and the storage medium  114  (step A 1  in FIG.  2 ). 
     For example, when there is no difference between a file A in the storage medium  121  in the computer  12  and a file A in the storage medium  114  in the software installation system  11 , no file operation is performed, or when the file A in the storage medium  114  in the software installation system  11  is newer than the file A′ in the storage medium  121  in the computer  12 , the file A is copied from the storage medium  114  to the storage medium  121 . 
     This step may be omitted when a default operation is preset, and an operator may not select the operation. 
     The difference detector  111  compares the files in the storage medium  121  in the computer  12  and the files in the storage medium  114  in the software installation system  11 , to detect the differences (step A 2 ), and outputs the list describing the differences (step A 3 ). 
     The difference detector  111  can find the difference by comparing time stamps, file sizes, file versions, and file data. 
     Based on the file difference list produced in step A 2  and the setting selected in step A 1 , the file operation determination device  112  outputs the list of operations for the files (step A 4 ). 
     Finally, based on the list output in step A 3 , the installer  113  performs copying or deletion of the files (step A 5 ). 
     The operation of the embodiment will be explained in more detail by way of an example. For instance, the computer  12  is supplied with the software installed therein. The storage medium  121  is a hard disc drive built into the computer. The software installation system  11  is to reset the computer  12  to the initial state as was delivered to the user. The contents in the storage medium  121  in the computer  12  was changed by the user. The storage medium  114  in the software installation system  11  stores the files which were initially stored in the storage medium  121  when the computer  12  was delivered to the user. 
     As shown in FIG. 3, the storage medium  121  in the computer  12  stores files A, B, D, and E. The storage medium  114  stores files A, B, C, and D. The file operation determination device  112  is instructed such that “no file operation is performed when the files in the storage medium  121  and the files in the storage medium  114  have no difference”, “the file is copied from the storage medium  114  to the storage medium  121  when the file in the storage medium  121  differs from the file in the storage medium  114 ”, “the file is deleted from the storage medium  121  when the corresponding file is not stored in the storage medium  114 ”, and “the file is copied from the storage medium  114  to the storage medium  121  when the file in the storage medium  114  is not stored in the storage medium  121 ”. 
     The difference detector  111  compares the files in the storage medium  121  with the files in the storage medium  114 , and outputs the difference list. For each file, the difference list in FIG. 3 indicates ∘ in the “data” section when the files are different, indicates ∘ in the “target” section when the file is stored in the storage medium  121 , and indicates ∘ in the “source” section when the file is stored in the storage medium  114 . 
     Based on the difference list, the file operation determination device  112  determines the operation for each file, and outputs the file operation list  32 . The file operation list  32  in FIG. 3 indicates “COPY” to copy the file from the storage medium  114  to the storage medium  121 , “DELETE” to delete the file from the storage medium  121 , or “−” to perform no operation. 
     According to the file operation list  32 , the installer  113  performs the operations for the files. Thus, the files in the storage medium  114  in the software installation system  11  can be installed, so that the files in the storage medium  121  in the computer  12  can be reset to the initial state as was delivered to the user. 
     The second embodiment of the present invention will be explained. The second embodiment has the same structure as the first embodiment in FIG.  1 . The second embodiment updates the version of the software installed in the storage medium  121  in the computer  12 . 
     The operation will be explained with reference to FIG.  4 . Initially, the user decides whether to maintain the current data or to delete all the data while installing new data. The file operation course selector  115  instructs the file operation course to the file operation determination device  112  (step B 1  in FIG.  4 ). 
     The difference detector  111  compares the files, which are installed in the storage medium  121  in the computer  12 , with the files in the storage medium  114  in the installation system  11  (step B 2 ), and outputs the list indicating the differences between the files (step B 3 ). 
     Based on the file difference list, the system indicates a warning message when the files installed in the storage medium  121  in the computer  12  are newer than the files to be installed (step B 7 ). 
     Then, the user determines whether to continue the installation of the old version (step B 8 ), and when the user stops the installation, the process is terminated. When the version of the software to be installed is newer or the user wishes to continue the installation, the file operation determination device  112  outputs the list indicating the operations for the files, based on the course setting in step B 1  and the file difference list obtained in step B 2  (step B 5 ). 
     Finally, the installer  113  performs the file operations according the list output in step B 3  (step B 6 ). 
     The operation of the second embodiment will be described in more detail by way of an example with reference to FIG.  5 . As shown in FIG. 5, the storage medium  121  in the computer stores the software files A, B, C, D. and E of the old version. The storage medium  114  stores the software files A, C, D, E, and F of the latest version. The file A is a setting file which records the user setting, the file B is a data file which the user produced, and the files C and D are of the updated version. 
     The file operation course determination device  115  instructs the file operation determination device  112  to maintain the file which includes the setting values for the software and the data used by the software. 
     The difference detector  111  compares the files in the storage medium  121  with the files in the storage medium  114 , and outputs the list  51  indicating the differences between the files as shown in FIG.  5 . For each file, the difference list in FIG. 5 indicates X in the “version” section when the versions of the files are different, indicates ∘ in the “version” section when the versions of the files are identical, indicates ∘ in the “target” section when the file is stored in the storage medium  121 , and indicates ∘ in the “source” section when the file is stored in the storage medium  114 . 
     Based on the difference list, the file operation determination device  112  determines the operation for each file, and outputs the file operation list  52 . Because in step B 1  the user selected to maintain the setting file for software and the data file used for software, the file operation list  52  in FIG. 5 indicates “copy” of the files, which are of the latest version or which  20  are stored only in the storage medium  114 , from the storage medium  114  to the storage medium  121 , and indicates for the other files which means that no operation is performed. 
     Finally, the installer  113  performs the operations for the files according to the file operation list  52 . Thus, the system can have the software updated while maintaining the user data and settings. 
     This invention may be embodied in other forms or carried out in other ways without departing from the spirit thereof The present embodiments are therefore to be considered in all respects illustrative and not limiting, the scope of the invention being indicated by the appended claims, and all modifications falling within the meaning and range of equivalency are intended to be embraced therein.