diff --git a/libraries/examples/annotation-processor-example/src/main/kotlin/example/ExampleAnnotationProcessor.kt b/libraries/examples/annotation-processor-example/src/main/kotlin/example/ExampleAnnotationProcessor.kt
index 0d12379f62a..714425fddd9 100644
--- a/libraries/examples/annotation-processor-example/src/main/kotlin/example/ExampleAnnotationProcessor.kt
+++ b/libraries/examples/annotation-processor-example/src/main/kotlin/example/ExampleAnnotationProcessor.kt
@@ -11,14 +11,14 @@ import javax.tools.Diagnostic
 public class ExampleAnnotationProcessor : AbstractProcessor() {
 
     private companion object {
-        val ANNOTATION_FQ_NAME = javaClass<ExampleAnnotation>().getCanonicalName()
+        val ANNOTATION_FQ_NAME = ExampleAnnotation::class.java.getCanonicalName()
         val SUFFIX_OPTION = "suffix"
         val GENERATE_KOTLIN_CODE_OPTION = "generate.kotlin.code"
         val KAPT_KOTLIN_GENERATED_OPTION = "kapt.kotlin.generated"
     }
 
     override fun process(annotations: MutableSet<out TypeElement>?, roundEnv: RoundEnvironment): Boolean {
-        val elements = roundEnv.getElementsAnnotatedWith(javaClass<ExampleAnnotation>())
+        val elements = roundEnv.getElementsAnnotatedWith(ExampleAnnotation::class.java)
 
         val elementUtils = processingEnv.getElementUtils()
         val filer = processingEnv.getFiler()
diff --git a/libraries/stdlib/src/kotlin/io/files/FileTreeWalk.kt b/libraries/stdlib/src/kotlin/io/files/FileTreeWalk.kt
index dc4cdfcfc45..54fe7a1fa84 100644
--- a/libraries/stdlib/src/kotlin/io/files/FileTreeWalk.kt
+++ b/libraries/stdlib/src/kotlin/io/files/FileTreeWalk.kt
@@ -6,7 +6,6 @@ package kotlin.io
 import java.io.File
 import java.io.IOException
 import java.util.Stack
-import kotlin.support.AbstractIterator
 
 /**
  * An enumeration to describe possible walk directions.
diff --git a/libraries/stdlib/src/kotlin/text/StringsJVM.kt b/libraries/stdlib/src/kotlin/text/StringsJVM.kt
index 464b37eb56f..c32db047ce4 100644
--- a/libraries/stdlib/src/kotlin/text/StringsJVM.kt
+++ b/libraries/stdlib/src/kotlin/text/StringsJVM.kt
@@ -438,7 +438,7 @@ public fun String.toPattern(flags: Int = 0): java.util.regex.Pattern {
  * @sample test.text.StringTest.capitalize
  */
 public fun String.capitalize(): String {
-    return if (isNotEmpty() && charAt(0).isLowerCase()) substring(0, 1).toUpperCase() + substring(1) else this
+    return if (isNotEmpty() && this[0].isLowerCase()) substring(0, 1).toUpperCase() + substring(1) else this
 }
 
 /**
@@ -448,7 +448,7 @@ public fun String.capitalize(): String {
  * @sample test.text.StringTest.decapitalize
  */
 public fun String.decapitalize(): String {
-    return if (isNotEmpty() && charAt(0).isUpperCase()) substring(0, 1).toLowerCase() + substring(1) else this
+    return if (isNotEmpty() && this[0].isUpperCase()) substring(0, 1).toLowerCase() + substring(1) else this
 }
 
 /**
diff --git a/libraries/stdlib/test/AnnotationsTest.kt b/libraries/stdlib/test/AnnotationsTest.kt
index 5190dce9899..d5bc7f31674 100644
--- a/libraries/stdlib/test/AnnotationsTest.kt
+++ b/libraries/stdlib/test/AnnotationsTest.kt
@@ -1,7 +1,6 @@
 package test.annotations
 
-import kotlin.*
-import kotlin.test.assertTrue
+import kotlin.test.*
 import org.junit.Test as test
 
 @Retention(AnnotationRetention.RUNTIME)
@@ -14,21 +13,10 @@ class AnnotatedClass
 
 class AnnotationTest {
     @test fun annotationType() {
-        val annotations = javaClass<AnnotatedClass>().getAnnotations()!!
-        
-        var foundMyAnno = false
-        var foundDeprecated = false
-        
-        for (annotation in annotations) {
-            val clazz = annotation!!.annotationType()
-            when {
-                clazz == javaClass<MyAnno>() -> foundMyAnno = true
-                clazz == javaClass<java.lang.Deprecated>() -> foundDeprecated = true
-                else -> {}
-            }
-        }
-        
-        assertTrue(foundMyAnno)
-        assertTrue(foundDeprecated)
+        val kAnnotations = AnnotatedClass::class.java.annotations.map { it!!.annotationClass }
+        val jAnnotations = AnnotatedClass::class.java.annotations.map { it!!.annotationClass.java }
+
+        assertTrue(kAnnotations.containsAll(listOf(MyAnno::class,       java.lang.Deprecated::class)))
+        assertTrue(jAnnotations.containsAll(listOf(MyAnno::class.java,  java.lang.Deprecated::class.java)))
     }
 }
diff --git a/libraries/stdlib/test/JavaClassTest.kt b/libraries/stdlib/test/JavaClassTest.kt
index b0b7f5dacc4..0a998352bb7 100644
--- a/libraries/stdlib/test/JavaClassTest.kt
+++ b/libraries/stdlib/test/JavaClassTest.kt
@@ -2,13 +2,14 @@ package testjc
 
 import kotlin.test.*
 import junit.framework.TestCase
+import java.util.*
 
 class C()
 
 class JavaClassTest() : TestCase() {
     fun testMe () {
         assertEquals("java.util.ArrayList", java.util.ArrayList<Any>().javaClass.getName())
-        assertEquals("java.util.ArrayList", javaClass<java.util.ArrayList<Any>>().getName())
-        assertEquals("testjc.C", javaClass<C>().getName())
+        assertEquals("java.util.ArrayList", ArrayList::class.java.getName())
+        assertEquals("testjc.C", C::class.java.getName())
     }
 }
\ No newline at end of file
diff --git a/libraries/stdlib/test/collections/MapJVMTest.kt b/libraries/stdlib/test/collections/MapJVMTest.kt
index d6cc6b6759c..19e9e2254c5 100644
--- a/libraries/stdlib/test/collections/MapJVMTest.kt
+++ b/libraries/stdlib/test/collections/MapJVMTest.kt
@@ -43,7 +43,7 @@ class MapJVMTest {
     }
 
     @test fun iterateAndRemove() {
-        val map = (1..5).toMap({ it }, { 'a' + it }).toLinkedMap()
+        val map = (1..5).toMapBy({ it }, { 'a' + it }).toLinkedMap()
         val iterator = map.iterator()
         while (iterator.hasNext()) {
             if (iterator.next().key % 2 == 0)
diff --git a/libraries/stdlib/test/collections/MapTest.kt b/libraries/stdlib/test/collections/MapTest.kt
index 39e3f20c187..e3b76d32da7 100644
--- a/libraries/stdlib/test/collections/MapTest.kt
+++ b/libraries/stdlib/test/collections/MapTest.kt
@@ -187,7 +187,7 @@ class MapTest {
     }
 
     @test fun createWithSelectorForKeyAndValue() {
-        val map = listOf("a", "bb", "ccc").toMap({ it.length }, { it.toUpperCase() })
+        val map = listOf("a", "bb", "ccc").toMapBy({ it.length }, { it.toUpperCase() })
         assertEquals(3, map.size)
         assertEquals("A", map[1])
         assertEquals("BB", map[2])
diff --git a/libraries/stdlib/test/io/IOStreams.kt b/libraries/stdlib/test/io/IOStreams.kt
index cc8c3cf9e09..5b855591126 100644
--- a/libraries/stdlib/test/io/IOStreams.kt
+++ b/libraries/stdlib/test/io/IOStreams.kt
@@ -11,7 +11,7 @@ class IOStreamsTest {
         var writer: Writer? = null
         try {
             writer = tmpFile.outputStream().writer()
-            writer!!.write("Hello, World!")
+            writer.write("Hello, World!")
         } finally {
             writer?.close()
         }
@@ -19,7 +19,7 @@ class IOStreamsTest {
         var reader: BufferedReader? = null
         try {
             reader = tmpFile.inputStream().reader().buffered()
-            act = reader!!.readLine()
+            act = reader.readLine()
         } finally {
             reader?.close()
         }
diff --git a/libraries/stdlib/test/js/MapJsTest.kt b/libraries/stdlib/test/js/MapJsTest.kt
index 6916fea13fd..c1f03a626f0 100644
--- a/libraries/stdlib/test/js/MapJsTest.kt
+++ b/libraries/stdlib/test/js/MapJsTest.kt
@@ -189,7 +189,7 @@ abstract class MapJsTest {
                    map.containsKey(KEYS[3]))
 
         assertFalse(map.containsKey("foo") ||
-                    map.containsKey(1))
+                    map.containsKey(1 as Any))
     }
 
     @test fun mapContainsValue() {
@@ -200,7 +200,7 @@ abstract class MapJsTest {
                    map.containsValue(VALUES[2]) &&
                    map.containsValue(VALUES[3]))
 
-        assertFalse(map.containsValue("four") ||
+        assertFalse(map.containsValue("four" as Any) ||
                     map.containsValue(5))
     }
 
diff --git a/libraries/tools/kotlin-annotation-processing/src/main/kotlin/org/jetbrains/kotlin/annotation/RoundEnvironmentWrapper.kt b/libraries/tools/kotlin-annotation-processing/src/main/kotlin/org/jetbrains/kotlin/annotation/RoundEnvironmentWrapper.kt
index 9c073fa3bec..f52b9e79681 100644
--- a/libraries/tools/kotlin-annotation-processing/src/main/kotlin/org/jetbrains/kotlin/annotation/RoundEnvironmentWrapper.kt
+++ b/libraries/tools/kotlin-annotation-processing/src/main/kotlin/org/jetbrains/kotlin/annotation/RoundEnvironmentWrapper.kt
@@ -86,7 +86,7 @@ internal class RoundEnvironmentWrapper(
 
         if (kotlinAnnotationsProvider.supportInheritedAnnotations) {
             val isInherited = processingEnv.getElementUtils().getTypeElement(annotationFqName)
-                    ?.hasAnnotation(javaClass<Inherited>().getCanonicalName()) ?: false
+                    ?.hasAnnotation(Inherited::class.java.getCanonicalName()) ?: false
 
             if (isInherited) {
                 kotlinAnnotationsProvider.kotlinClasses.forEach { classFqName ->
diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/AnnotationProcessingManager.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/AnnotationProcessingManager.kt
index 3a21e3e3bb7..0b3c7bd39b2 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/AnnotationProcessingManager.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/internal/AnnotationProcessingManager.kt
@@ -35,7 +35,7 @@ fun Project.initKapt(
         subpluginEnvironment: SubpluginEnvironment,
         taskFactory: (suffix: String) -> AbstractCompile
 ): AbstractCompile? {
-    val kaptExtension = extensions.getByType(javaClass<KaptExtension>())
+    val kaptExtension = extensions.getByType(KaptExtension::class.java)
     val kotlinAfterJavaTask: AbstractCompile?
 
     if (kaptExtension.generateStubs) {
@@ -193,7 +193,7 @@ public class AnnotationProcessingManager(
     }
 
     private fun appendAdditionalComplerArgs() {
-        val kaptExtension = project.extensions.getByType(javaClass<KaptExtension>())
+        val kaptExtension = project.extensions.getByType(KaptExtension::class.java)
         val args = kaptExtension.getAdditionalArguments(project, androidVariant, getAndroidExtension())
         if (args.isEmpty()) return
 
diff --git a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt
index 5b90e9d3b5f..bd214aa9277 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt
@@ -218,7 +218,7 @@ class Kotlin2JsSourceSetProcessor(
 
     private fun createCleanSourceMapTask() {
         val taskName = sourceSet.getTaskName("clean", "sourceMap")
-        val task = project.getTasks().create(taskName, javaClass<Delete>())
+        val task = project.getTasks().create(taskName, Delete::class.java)
         task.onlyIf { kotlinTask.property("sourceMap") as Boolean }
         task.delete(object : Closure<String>(this) {
             override fun call(): String? = (kotlinTask.property("outputFile") as String) + ".map"
@@ -232,10 +232,10 @@ abstract class AbstractKotlinPlugin @Inject constructor(val scriptHandler: Scrip
     abstract fun buildSourceSetProcessor(project: ProjectInternal, javaBasePlugin: JavaBasePlugin, sourceSet: SourceSet): KotlinSourceSetProcessor<*>
 
     public override fun apply(project: Project) {
-        val javaBasePlugin = project.getPlugins().apply(javaClass<JavaBasePlugin>())
-        val javaPluginConvention = project.getConvention().getPlugin(javaClass<JavaPluginConvention>())
+        val javaBasePlugin = project.getPlugins().apply(JavaBasePlugin::class.java)
+        val javaPluginConvention = project.getConvention().getPlugin(JavaPluginConvention::class.java)
 
-        project.getPlugins().apply(javaClass<JavaPlugin>())
+        project.getPlugins().apply(JavaPlugin::class.java)
 
         configureSourceSetDefaults(project as ProjectInternal, javaBasePlugin, javaPluginConvention)
     }
@@ -456,7 +456,7 @@ open class KotlinAndroidPlugin @Inject constructor(val scriptHandler: ScriptHand
 private fun loadSubplugins(project: Project): SubpluginEnvironment {
     try {
         val subplugins = ServiceLoader.load(
-            javaClass<KotlinGradleSubplugin>(), project.getBuildscript().getClassLoader()).toList()
+                KotlinGradleSubplugin::class.java, project.getBuildscript().getClassLoader()).toList()
         val subpluginDependencyNames =
             subplugins.mapTo(hashSetOf<String>()) { it.getGroupName() + ":" + it.getArtifactName() }
 
@@ -556,13 +556,13 @@ private fun Project.createAptConfiguration(sourceSetName: String, kotlinAnnotati
 }
 
 private fun Project.createKaptExtension() {
-    getExtensions().create("kapt", javaClass<KaptExtension>())
+    getExtensions().create("kapt", KaptExtension::class.java)
 }
 
 //copied from BasePlugin.getLocalVersion
 private fun loadAndroidPluginVersion(): String? {
     try {
-        val clazz = javaClass<BasePlugin>()
+        val clazz = BasePlugin::class.java
         val className = clazz.getSimpleName() + ".class"
         val classPath = clazz.getResource(className).toString()
         if (!classPath.startsWith("jar")) {
diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
index 58cb7c7844b..c247bbffa33 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/kotlin/org/jetbrains/kotlin/gradle/BaseGradleIT.kt
@@ -126,7 +126,7 @@ abstract class BaseGradleIT {
         val tailParameters = params.asList() +
                 listOf( pathToKotlinPlugin,
                         if (options.withDaemon) "--daemon" else "--no-daemon",
-                        "--${minLogLevel.name().toLowerCase()}",
+                        "--${minLogLevel.name.toLowerCase()}",
                         "-Pkotlin.gradle.test=true")
 
         return createGradleCommand(tailParameters)
diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptArguments/src/main/java/test.kt b/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptArguments/src/main/java/test.kt
index 97543eceb02..3a0a9b24793 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptArguments/src/main/java/test.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptArguments/src/main/java/test.kt
@@ -7,6 +7,6 @@ public class TestClass {
     public val testVal: String = "text"
 
     @example.ExampleAnnotation
-    public fun testFunction(): Class<*> = javaClass<TestClassCustomized>()
+    public fun testFunction(): Class<*> = TestClassCustomized::class.java
 
 }
\ No newline at end of file
diff --git a/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptStubs/src/main/java/test.kt b/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptStubs/src/main/java/test.kt
index 37872cd6085..a0825234e36 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptStubs/src/main/java/test.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/test/resources/testProject/kaptStubs/src/main/java/test.kt
@@ -7,6 +7,6 @@ public class TestClass {
     public val testVal: String = "text"
 
     @example.ExampleAnnotation
-    public fun testFunction(): Class<*> = javaClass<TestClassGenerated>()
+    public fun testFunction(): Class<*> = TestClassGenerated::class.java
 
 }
\ No newline at end of file