Refactoring support for class library migration

Abstract

As object-oriented class libraries evolve, classes are occasionally deprecated in favor of others with roughly the same functionality. In Java's standard libraries, for example, class Hashtable has been superseded by HashMap, and Iterator is now preferred over Enumeration. Migrating client applications to use the new idioms is often desirable, but making the required changes to declarations and allocation sites can be quite labor-intensive. Moreover, migration becomes complicated-and sometimes impossible-if an application interacts with external components, if a legacy class is not completely equivalent to its replacement, or if multiple interdependent classes must be migrated simultaneously. We present an approach in which mappings between legacy classes and their replacements are specified by the programmer. Then, an analysis based on type constraints determines where declarations and allocation sites can be updated. The method was implemented in Eclipse, and evaluated on a number of Java applications. On average, our tool could migrate more than 90% of the references to legacy classes.

Automated Detection of Refactorings in Evolving Components

“…Dincklage and Diwan [vDD04] use various heuristics to convert from non-generic classes to generic classes. Balaban et al [BTF05] propose refactorings that automatically replace obsolete library classes with their newer counterparts. Component developers have to provide mappings between legacy classes and their replacements, and an analysis based on type constraints determines where the replacement can be done.…”

Refactoring sequential Java code for concurrency via concurrent libraries

“…Balaban et al [1] present a tool for converting between obsolete classes and their modern replacements. The programmer specifies a mapping between the old APIs and the new APIs, and the tool uses a type-constraint analysis to determine whether it can replace all usages of the obsolete class.…”

Study of an API Migration for Two XML APIs

“…Several approaches go beyond the limits of refactoring by providing some general means of transformation [CN96,KH98,BTF05,PLHM08]. Again, the showcases for all these approaches concern API evolution or migration between very much similar APIs.…”

“…Again, the showcases for all these approaches concern API evolution or migration between very much similar APIs. For instance, [BTF05] describes a rewriting-based approach for API migration that has been applied to the types Vector and ArrayList of the Java Core API, where the latter type is essentially a 'careful redesign' of the former. Nevertheless, the transformation techniques from such previous work are important ingredients of a general approach to API migration.…”