Iterators replaced with streams where appropriate

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/annotationUtils.kt

@@ -43,7 +43,7 @@ class LazyJavaAnnotations(c: LazyJavaResolverContextWithTypes, val annotationOwn
 
     [suppress("UNCHECKED_CAST")] // any iterator can be cast to MutableIterator
     override fun iterator(): MutableIterator<AnnotationDescriptor>
-            = annotationOwner.getAnnotations().iterator().map { annotationDescriptors(it) }.filterNotNull() as MutableIterator
+            = annotationOwner.getAnnotations().stream().map { annotationDescriptors(it) }.filterNotNull().iterator() as MutableIterator
 
     override fun isEmpty() = iterator().hasNext()
 }

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/descriptors/LazyJavaClassDescriptor.kt

@@ -196,7 +196,7 @@ class LazyJavaClassDescriptor(
                     listOf(jlObject ?: KotlinBuiltIns.getInstance().getAnyType())
                 }
             else
-                supertypes.iterator()
+                supertypes.stream()
                         .map {
                             supertype ->
                             c.typeResolver.transformJavaType(supertype, TypeUsage.SUPERTYPE.toAttributes())

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/descriptors/LazyJavaMemberScope.kt

@@ -61,7 +61,7 @@ public abstract class LazyJavaMemberScope(
         ->
         val methods = memberIndex().findMethodsByName(name)
         val functions = LinkedHashSet(
-                methods.iterator()
+                methods.stream()
                       // values() and valueOf() are added manually, see LazyJavaClassDescriptor::getClassObjectDescriptor()
                       .filter{ m -> !DescriptorResolverUtils.shouldBeInEnumClassObject(m) }
                       .flatMap {
@@ -69,9 +69,9 @@ public abstract class LazyJavaMemberScope(
                               val function = resolveMethodToFunctionDescriptor(m, true)
                               val samAdapter = resolveSamAdapter(function)
                               if (samAdapter != null)
-                                  listOf(function, samAdapter).iterator()
+                                  listOf(function, samAdapter).stream()
                               else
-                                  listOf(function).iterator()
+                                  listOf(function).stream()
                       }.toList())
 
         if (_containingDeclaration is JavaPackageFragmentDescriptor) {

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/descriptors/LazyJavaPackageFragmentScope.kt

@@ -90,7 +90,7 @@ public class LazyPackageFragmentScopeForJavaPackage(
     override fun computeMemberIndex(): MemberIndex = computeMemberIndexForSamConstructors(EMPTY_MEMBER_INDEX)
 
     override fun getAllClassNames(): Collection<Name> {
-        return jPackage.getClasses().iterator()
+        return jPackage.getClasses().stream()
                 .filter { c -> c.getOriginKind() != JavaClass.OriginKind.KOTLIN_LIGHT_CLASS }
                 .map { c -> c.getName() }.toList()
     }
@@ -126,7 +126,7 @@ public class LazyPackageFragmentScopeForJavaClass(
 
     // We do not filter by hasStaticMembers() because it's slow (e.g. it triggers light class generation),
     // and there's no harm in having some names in the result that can not be resolved
-    override fun getSubPackages(): Collection<FqName> = jClass.getInnerClasses().iterator()
+    override fun getSubPackages(): Collection<FqName> = jClass.getInnerClasses().stream()
                                                                 .filter { c -> c.isStatic() }
                                                                 .map { c -> c.getFqName().sure("Nested class has no fqName: $c}") }.toList()
 }

core/descriptor.loader.java/src/org/jetbrains/jet/lang/resolve/java/lazy/descriptors/MemberIndex.kt

@@ -55,8 +55,8 @@ open class ClassMemberIndex(val jClass: JavaClass, filter: (JavaMember) -> Boole
         !DescriptorResolverUtils.isObjectMethodInInterface(m)
     }
 
-    private val methods = jClass.getMethods().iterator().filter(methodFilter).groupBy { m -> m.getName() }
+    private val methods = jClass.getMethods().stream().filter(methodFilter).groupBy { m -> m.getName() }
-    private val fields = jClass.getFields().iterator().filter(memberFilter).valuesToMap { m -> m.getName() }
+    private val fields = jClass.getFields().stream().filter(memberFilter).valuesToMap { m -> m.getName() }
 
     override fun findMethodsByName(name: Name): Collection<JavaMethod> {
         return methods[name] ?: listOf()
@@ -65,5 +65,5 @@ open class ClassMemberIndex(val jClass: JavaClass, filter: (JavaMember) -> Boole
     override fun getAllMethodNames(): Collection<Name> = jClass.getAllMethods().iterator().filter(methodFilter).map { m -> m.getName() }.toList()
 
     override fun findFieldByName(name: Name): JavaField? = fields[name]
-    override fun getAllFieldNames() = jClass.getAllFields().iterator().filter(memberFilter).map { m -> m.getName() }.toList()
+    override fun getAllFieldNames() = jClass.getAllFields().stream().filter(memberFilter).map { m -> m.getName() }.toList()
 }

core/util.runtime/src/org/jetbrains/jet/utils/collections.kt

@@ -19,8 +19,7 @@ package org.jetbrains.jet.utils
 import java.util.LinkedHashMap
 import java.util.ArrayList
 
-[deprecated("use streams instead")]
+public fun <K, V> Stream<V>.valuesToMap(key: (V) -> K): Map<K, V> {
-public fun <K, V> Iterator<V>.valuesToMap(key: (V) -> K): Map<K, V> {
     val map = LinkedHashMap<K, V>()
     for (v in this) {
         map[key(v)] = v
@@ -28,8 +27,7 @@ public fun <K, V> Iterator<V>.valuesToMap(key: (V) -> K): Map<K, V> {
     return map
 }
 
-[deprecated("use streams instead")]
+public fun <K, V> Stream<K>.keysToMap(value: (K) -> V): Map<K, V> {
-public fun <K, V> Iterator<K>.keysToMap(value: (K) -> V): Map<K, V> {
     val map = LinkedHashMap<K, V>()
     for (k in this) {
         map[k] = value(k)
@@ -37,8 +35,7 @@ public fun <K, V> Iterator<K>.keysToMap(value: (K) -> V): Map<K, V> {
     return map
 }
 
-[deprecated("use streams instead")]
+public fun <K, V: Any> Stream<K>.keysToMapExceptNulls(value: (K) -> V?): Map<K, V> {
-public fun <K, V: Any> Iterator<K>.keysToMapExceptNulls(value: (K) -> V?): Map<K, V> {
     val map = LinkedHashMap<K, V>()
     for (k in this) {
         val v = value(k)

idea/src/org/jetbrains/jet/plugin/hierarchy/overrides/KotlinOverrideTreeStructure.kt

@@ -57,7 +57,7 @@ class KotlinOverrideTreeStructure(project: Project, val element: PsiElement) : H
         }
 
         return javaTreeStructures
-                .iterator()
+                .stream()
                 .map (::buildChildrenByTreeStructure)
                 .reduce { (a, b) -> ContainerUtil.union(a.toSet(), b.toSet()).copyToArray() }
     }

idea/src/org/jetbrains/jet/plugin/refactoring/move/moveTopLevelDeclarations/MoveKotlinTopLevelDeclarationsProcessor.kt

@@ -265,7 +265,7 @@ public class MoveKotlinTopLevelDeclarationsProcessor(project: Project, val optio
                 }
 
                 getTransaction()!!.getElementListener(oldDeclaration).elementMoved(newDeclaration)
-                for ((oldElement, newElement) in oldLightElements.iterator() zip newDeclaration.toLightElements().iterator()) {
+                for ((oldElement, newElement) in oldLightElements.stream() zip newDeclaration.toLightElements().stream()) {
                     oldToNewElementsMapping[oldElement] = newElement
                 }
             }

idea/src/org/jetbrains/jet/plugin/refactoring/safeDelete/KotlinSafeDeleteProcessor.kt

@@ -105,7 +105,7 @@ public class KotlinSafeDeleteProcessor : JavaSafeDeleteProcessor() {
             return searchInfo
         }
 
-        fun findUsagesByJavaProcessor(elements: Iterator<PsiElement>, insideDeleted: Condition<PsiElement>): Condition<PsiElement> =
+        fun findUsagesByJavaProcessor(elements: Stream<PsiElement>, insideDeleted: Condition<PsiElement>): Condition<PsiElement> =
                 elements
                         .map { element -> findUsagesByJavaProcessor(element, true)?.getInsideDeletedCondition() }
                         .filterNotNull()
@@ -114,7 +114,7 @@ public class KotlinSafeDeleteProcessor : JavaSafeDeleteProcessor() {
         fun findUsagesByJavaProcessor(jetDeclaration: JetDeclaration): NonCodeUsageSearchInfo {
             return NonCodeUsageSearchInfo(
                     findUsagesByJavaProcessor(
-                            jetDeclaration.toLightElements().iterator(),
+                            jetDeclaration.toLightElements().stream(),
                             getIgnoranceCondition()
                     ),
                     jetDeclaration
@@ -123,7 +123,7 @@ public class KotlinSafeDeleteProcessor : JavaSafeDeleteProcessor() {
 
         fun findKotlinDeclarationUsages(declaration: JetDeclaration): NonCodeUsageSearchInfo {
             ReferencesSearch.search(declaration, declaration.getUseScope())
-                    .iterator()
+                    .stream()
                     .filterNot { reference -> getIgnoranceCondition().value(reference.getElement()) }
                     .mapTo(usages) { reference ->
                         reference.getElement().getParentByType(javaClass<JetImportDirective>())?.let { importDirective ->
@@ -214,7 +214,7 @@ public class KotlinSafeDeleteProcessor : JavaSafeDeleteProcessor() {
             if (declarationDescriptor !is CallableMemberDescriptor) return null
 
             return declarationDescriptor.getOverriddenDescriptors()
-                    .iterator()
+                    .stream()
                     .filter { overridenDescriptor -> overridenDescriptor.getModality() == Modality.ABSTRACT }
                     .mapTo(ArrayList<String>()) { overridenDescriptor ->
                         JetBundle.message(

idea/src/org/jetbrains/jet/plugin/refactoring/safeDelete/utils.kt

@@ -64,7 +64,7 @@ fun PsiElement.removeOverrideModifier() {
 fun PsiMethod.cleanUpOverrides() {
     val superMethods = findSuperMethods(true)
     for (overridingMethod in OverridingMethodsSearch.search(this, true).findAll()) {
-        val currentSuperMethods = overridingMethod.findSuperMethods(true).iterator() + superMethods.iterator()
+        val currentSuperMethods = overridingMethod.findSuperMethods(true).stream() + superMethods.stream()
         if (currentSuperMethods.all { superMethod -> superMethod.unwrapped == unwrapped }) {
             overridingMethod.unwrapped?.removeOverrideModifier()
         }

idea/src/org/jetbrains/jet/plugin/search/ideaExtensions/KotlinDirectInheritorsSearcher.kt

@@ -46,7 +46,7 @@ public open class KotlinDirectInheritorsSearcher() : QueryExecutorBase<PsiClass,
         if (scope == null) return
 
         ApplicationManager.getApplication()?.runReadAction {
-            JetSuperClassIndex.getInstance().get(name, baseClass.getProject(), scope).iterator()
+            JetSuperClassIndex.getInstance().get(name, baseClass.getProject(), scope).stream()
                     .map { candidate -> JetSourceNavigationHelper.getOriginalPsiClassOrCreateLightClass(candidate)}
                     .filterNotNull()
                     .filter { candidate -> candidate.isInheritor(baseClass, false) }