Streamify RTA

sootup.callgraph/src/main/java/sootup/callgraph/RapidTypeAnalysisAlgorithm.java

@@ -36,6 +36,7 @@
 import sootup.core.model.SootMethod;
 import sootup.core.signatures.MethodSignature;
 import sootup.core.types.ClassType;
+import sootup.core.util.StreamUtils;
 import sootup.core.views.View;
 
 /**
@@ -88,24 +89,16 @@ public CallGraph initialize(@Nonnull List<MethodSignature> entryPoints) {
    *
    * @param method this object contains the method body which is inspected.
    */
-  protected List<ClassType> collectInstantiatedClassesInMethod(SootMethod method) {
-    if (method == null || method.isAbstract() || method.isNative()) {
-      return Collections.emptyList();
-    }
-
+  protected Stream<ClassType> collectInstantiatedClassesInMethod(SootMethod method) {
     Set<ClassType> instantiated =
         method.getBody().getStmts().stream()
             .filter(stmt -> stmt instanceof JAssignStmt)
             .map(stmt -> ((JAssignStmt) stmt).getRightOp())
             .filter(value -> value instanceof JNewExpr)
             .map(value -> ((JNewExpr) value).getType())
             .collect(Collectors.toSet());
-    List<ClassType> newInstantiatedClassTypes =
-        instantiated.stream()
-            .filter(classType -> !instantiatedClasses.contains(classType))
-            .collect(Collectors.toList());
     instantiatedClasses.addAll(instantiated);
-    return newInstantiatedClassTypes;
+    return instantiated.stream().filter(classType -> !instantiatedClasses.contains(classType));
   }
 
   /**
@@ -223,17 +216,10 @@ protected void preProcessingMethod(
       MethodSignature sourceMethod,
       @Nonnull Deque<MethodSignature> workList,
       @Nonnull MutableCallGraph cg) {
-    SootMethod method =
-        view.getClass(sourceMethod.getDeclClassType())
-            .flatMap(c -> c.getMethod(sourceMethod.getSubSignature()))
-            .orElse(null);
-    if (method == null) {
-      return;
-    }
-
-    List<ClassType> newInstantiatedClasses = collectInstantiatedClassesInMethod(method);
-    newInstantiatedClasses.forEach(
-        classType -> includeIgnoredCallsToClass(classType, cg, workList));
+    StreamUtils.optionalToStream(view.getMethod(sourceMethod))
+        .filter(SootMethod::isConcrete)
+        .flatMap(this::collectInstantiatedClassesInMethod)
+        .forEach(classType -> includeIgnoredCallsToClass(classType, cg, workList));
   }
 
   /**
@@ -250,17 +236,15 @@ protected void includeIgnoredCallsToClass(
     if (newEdges != null) {
       newEdges.forEach(
           call -> {
-            MethodSignature concreteTarget =
-                resolveConcreteDispatch(view, call.getTargetMethodSignature()).orElse(null);
-            if (concreteTarget == null) {
-              return;
-            }
-            addCallToCG(
-                call.getSourceMethodSignature(),
-                concreteTarget,
-                call.getInvokableStmt(),
-                cg,
-                workList);
+            resolveConcreteDispatch(view, call.getTargetMethodSignature())
+                .ifPresent(
+                    concreteTarget ->
+                        addCallToCG(
+                            call.getSourceMethodSignature(),
+                            concreteTarget,
+                            call.getInvokableStmt(),
+                            cg,
+                            workList));
           });
       // can be removed because the instantiated class will be considered in future resolves
       ignoredCalls.remove(classType);