ClassCastExceptions and Nullpointers when applying recipe migrate-jax-rs

[vbotteman]

Describe the bug When I apply the recipe migrate-jax-rs on our Spring Boot 2.5 project, then I get ClassCastExceptions and NullPointerExceptions.

Stacktrace

ERROR o.s.s.o.RewriteExecutionContext - Exception occured!
org.openrewrite.UncaughtVisitorException: java.lang.ClassCastException: class org.openrewrite.java.tree.J$FieldAccess cannot be cast to class org.openrewrite.java.tree.J$Identifier (org.openrewrite.java.tree.J$FieldAccess and org.openrewrite.java.tree.J$Identifier are in unnamed module of loader org.springframework.boot.loader.LaunchedURLClassLoader @198e2867)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:253)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitFieldAccess(JavaVisitor.java:575)
        at org.springframework.sbm.java.migration.recipes.FindReplaceFieldAccessors$1.visitFieldAccess(FindReplaceFieldAccessors.java:64)
        at org.springframework.sbm.java.migration.recipes.FindReplaceFieldAccessors$1.visitFieldAccess(FindReplaceFieldAccessors.java:60)
        at org.openrewrite.java.tree.J$FieldAccess.acceptJava(J.java:1735)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitImport(JavaVisitor.java:674)
        at org.openrewrite.java.tree.J$Import.acceptJava(J.java:2395)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitRightPadded(JavaVisitor.java:1226)
        at org.openrewrite.java.JavaVisitor.lambda$visitCompilationUnit$9(JavaVisitor.java:465)
        at org.openrewrite.internal.ListUtils.lambda$map$0(ListUtils.java:141)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:123)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:141)
        at org.openrewrite.java.JavaVisitor.visitCompilationUnit(JavaVisitor.java:465)
        at org.openrewrite.java.JavaVisitor.visitJavaSourceFile(JavaVisitor.java:454)
        at org.openrewrite.java.tree.J$CompilationUnit.acceptJava(J.java:1351)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.RecipeScheduler.lambda$scheduleVisit$5(RecipeScheduler.java:241)
        at org.openrewrite.RecipeScheduler.lambda$mapAsync$0(RecipeScheduler.java:49)
        at org.openrewrite.scheduling.ForkJoinScheduler.lambda$schedule$0(ForkJoinScheduler.java:41)
        at java.base/java.util.concurrent.ForkJoinTask$AdaptedRunnableAction.exec(ForkJoinTask.java:1375)
        at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
        at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
        at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
        at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
        at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
Caused by: java.lang.ClassCastException: class org.openrewrite.java.tree.J$FieldAccess cannot be cast to class org.openrewrite.java.tree.J$Identifier (org.openrewrite.java.tree.J$FieldAccess and org.openrewrite.java.tree.J$Identifier are in unnamed module of loader org.springframework.boot.loader.LaunchedURLClassLoader @198e2867)
        at org.openrewrite.java.tree.J$FieldAccess.getName(J.java:1721)
        at org.springframework.sbm.java.migration.recipes.FindReplaceFieldAccessors$1.visitFieldAccess(FindReplaceFieldAccessors.java:68)
        at org.springframework.sbm.java.migration.recipes.FindReplaceFieldAccessors$1.visitFieldAccess(FindReplaceFieldAccessors.java:60)
        at org.openrewrite.java.tree.J$FieldAccess.acceptJava(J.java:1735)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        ... 32 common frames omitted

ERROR o.s.s.o.RewriteExecutionContext - Exception occured!
org.openrewrite.UncaughtVisitorException: java.lang.NullPointerException: Cannot invoke "org.openrewrite.java.tree.Expression.getMarkers()" because the return value of "org.openrewrite.java.tree.J$Return.getExpression()" is null
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:253)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitRightPadded(JavaVisitor.java:1226)
        at org.openrewrite.java.JavaVisitor.lambda$visitBlock$4(JavaVisitor.java:367)
        at org.openrewrite.internal.ListUtils.lambda$map$0(ListUtils.java:141)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:123)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:141)
        at org.openrewrite.java.JavaVisitor.visitBlock(JavaVisitor.java:366)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:94)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$Block.acceptJava(J.java:745)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitRightPadded(JavaVisitor.java:1226)
        at org.openrewrite.java.JavaVisitor.visitIf(JavaVisitor.java:664)
        at org.openrewrite.java.JavaIsoVisitor.visitIf(JavaIsoVisitor.java:190)
        at org.openrewrite.java.JavaIsoVisitor.visitIf(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$If.acceptJava(J.java:2253)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitRightPadded(JavaVisitor.java:1226)
        at org.openrewrite.java.JavaVisitor.lambda$visitBlock$4(JavaVisitor.java:367)
        at org.openrewrite.internal.ListUtils.lambda$map$0(ListUtils.java:141)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:123)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:141)
        at org.openrewrite.java.JavaVisitor.visitBlock(JavaVisitor.java:366)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:94)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$Block.acceptJava(J.java:745)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitMethodDeclaration(JavaVisitor.java:810)
        at org.openrewrite.java.JavaIsoVisitor.visitMethodDeclaration(JavaIsoVisitor.java:225)
        at org.openrewrite.java.JavaIsoVisitor.visitMethodDeclaration(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$MethodDeclaration.acceptJava(J.java:3221)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitRightPadded(JavaVisitor.java:1226)
        at org.openrewrite.java.JavaVisitor.lambda$visitBlock$4(JavaVisitor.java:367)
        at org.openrewrite.internal.ListUtils.lambda$map$0(ListUtils.java:141)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:123)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:141)
        at org.openrewrite.java.JavaVisitor.visitBlock(JavaVisitor.java:366)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:94)
        at org.openrewrite.java.JavaIsoVisitor.visitBlock(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$Block.acceptJava(J.java:745)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.visitClassDeclaration(JavaVisitor.java:447)
        at org.openrewrite.java.JavaIsoVisitor.visitClassDeclaration(JavaIsoVisitor.java:114)
        at org.openrewrite.java.JavaIsoVisitor.visitClassDeclaration(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$ClassDeclaration.acceptJava(J.java:1069)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.TreeVisitor.visitAndCast(TreeVisitor.java:285)
        at org.openrewrite.java.JavaVisitor.lambda$visitCompilationUnit$10(JavaVisitor.java:466)
        at org.openrewrite.internal.ListUtils.lambda$map$0(ListUtils.java:141)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:123)
        at org.openrewrite.internal.ListUtils.map(ListUtils.java:141)
        at org.openrewrite.java.JavaVisitor.visitCompilationUnit(JavaVisitor.java:466)
        at org.openrewrite.java.JavaIsoVisitor.visitCompilationUnit(JavaIsoVisitor.java:119)
        at org.openrewrite.java.JavaIsoVisitor.visitCompilationUnit(JavaIsoVisitor.java:31)
        at org.openrewrite.java.JavaVisitor.visitJavaSourceFile(JavaVisitor.java:454)
        at org.openrewrite.java.JavaIsoVisitor.visitJavaSourceFile(JavaIsoVisitor.java:39)
        at org.openrewrite.java.JavaIsoVisitor.visitJavaSourceFile(JavaIsoVisitor.java:31)
        at org.openrewrite.java.tree.J$CompilationUnit.acceptJava(J.java:1351)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        at org.openrewrite.RecipeScheduler.lambda$scheduleVisit$5(RecipeScheduler.java:241)
        at org.openrewrite.RecipeScheduler.lambda$mapAsync$0(RecipeScheduler.java:49)
        at org.openrewrite.scheduling.ForkJoinScheduler.lambda$schedule$0(ForkJoinScheduler.java:41)
        at java.base/java.util.concurrent.ForkJoinTask$AdaptedRunnableAction.exec(ForkJoinTask.java:1375)
        at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
        at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
        at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
        at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
        at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
Caused by: java.lang.NullPointerException: Cannot invoke "org.openrewrite.java.tree.Expression.getMarkers()" because the return value of "org.openrewrite.java.tree.J$Return.getExpression()" is null
        at org.springframework.sbm.java.migration.visitor.VisitorUtils$AdjustTypesFromExpressionMarkers$1.visitReturn(VisitorUtils.java:164)
        at org.springframework.sbm.java.migration.visitor.VisitorUtils$AdjustTypesFromExpressionMarkers$1.visitReturn(VisitorUtils.java:159)
        at org.openrewrite.java.tree.J$Return.acceptJava(J.java:4417)
        at org.openrewrite.java.tree.J.accept(J.java:60)
        at org.openrewrite.TreeVisitor.visit(TreeVisitor.java:206)
        ... 81 common frames omitted

Desktop (please complete the following information):

• OS: Windows
• Version: 11 21H2

Additional context Java: graalvm-ce-java17-21.3.3

[vbotteman]

I was able to simulate the first error in a simple project, see attachment spring-boot-migrator-475.zip

[fabapp2]

Hi @vbotteman Thanks for reporting and for the demo application! I gave it a try and migrate-jax-rs does some useful things before it confirms successful execution. Actually, I doubt that any other elements will be migrated but I didn't check very thoroughly. The class cast exception comes from inside OpenRewrite. I need to debug a bit more to figure out where it exactly comes from.