java.lang.NullPointerException

[visoeclipse]

java.lang.NullPointerException
at soot.JastAddJ.Program.initPaths(Program.java:336)
at soot.SootResolver.initializeProgram(SootResolver.java:91)
at soot.SootResolver.getProgram(SootResolver.java:386)
at soot.JastAddInitialResolver.formAst(JastAddInitialResolver.java:62)
at soot.JavaClassSource.resolve(JavaClassSource.java:66)
at soot.SootResolver.bringToHierarchyUnchecked(SootResolver.java:253)
at soot.SootResolver.bringToHierarchy(SootResolver.java:221)
at soot.SootResolver.bringToSignatures(SootResolver.java:292)
at soot.SootResolver.processResolveWorklist(SootResolver.java:179)
at soot.SootResolver.resolveClass(SootResolver.java:141)
at soot.Scene.loadClass(Scene.java:1069)
at soot.Scene.loadClassAndSupport(Scene.java:1054)
at dev.navids.soottutorial.hellosoot.HelloSoot.setupSoot(HelloSoot.java:27)
at dev.navids.soottutorial.hellosoot.HelloSoot.main(HelloSoot.java:66)
20:24:07: Execution finished ':dev.navids.soottutorial.hellosoot.HelloSoot.main()'.

clone with nothing change，anybody can help me？