Program maintenance support device, program maintenance supporting method, and program for the same

The present invention includes program storing unit for storing a program, parsing/dependence-information generating unit for generating dependence information and a syntax tree for a program, dependence-information storing unit for storing dependence information, syntax-tree storing unit for storing a syntax tree, dependence-information tracking unit for extracting interface information on a program fragment according to specifying-information specifying the program fragment and extracting a part of a program fragment associated with interface information according to selection information for selecting the interface information, and information input/output unit for passing specifying-information and selection information to dependence-information tracking unit and outputting interface information and a part of a program fragment passed from dependence-information tracking unit