Java PathFinder (JPF) is a model checker for Java applications. Despite its maturity, JPF cannot be used to verify any realistic Java application without a nontrivial amount of work done by its user. One of the main limiting factors towards model checking such applications is handling native calls. JPF provides ways for users to handle such calls. However, those require modeling the behaviour of the native methods in Java which is labour intensive and hinders the uptake of JPF by developers. This paper presents our tool that extends JPF to address this problem. Our work alleviates this burden for users by automatically handling native calls. Our approach is based on delegating the execution of native calls from JPF to their original execution environment. We showcase our extension by applying it to a variety of simple yet realistic Java applications that JPF, without our extension, cannot handle.

In this paper we present JST, a tool that automatically generates a high coverage test suite for industrial strength Java applications. This tool uses a numeric-string hybrid symbolic execution engine at its core which is based on the Symbolic Java PathFinder platform. However, in order to make the tool applicable to industrial applications the existing generic platform had to be enhanced in numerous ways that we describe in this paper. The JST tool consists of newly supported essential Java library components and widely used data structures; novel solving techniques for string constraints, regular expressions, and their interactions with integer and floating point numbers; and key optimizations that make the tool more efficient. We present a methodology to seamlessly integrate the features mentioned above to make the tool scalable to industrial applications that are beyond the reach of the original platform in terms of both applicability and performance. We also present extensive experimental data to illustrate the effectiveness of our tool.