Java to Kotlin converter: generate "!!." instead of "?." for nullable values

#KT-3943 Fixed

j2k/src/org/jetbrains/jet/j2k/ast/Expressions.kt

@@ -73,14 +73,11 @@ class SuperExpression(val identifier: Identifier) : Expression() {
 
 class QualifiedExpression(val expression: Expression, val identifier: Expression) : Expression() {
     override val isNullable: Boolean
-        get() {
-            if (!expression.isEmpty && expression.isNullable) return true
-            return identifier.isNullable
-        }
+        get() = identifier.isNullable
 
     override fun toKotlin(): String {
         if (!expression.isEmpty) {
-            return operandToKotlin(expression) + (if (expression.isNullable) "?." else ".") + identifier.toKotlin()
+            return operandToKotlin(expression) + (if (expression.isNullable) "!!." else ".") + identifier.toKotlin()
         }
 
         return identifier.toKotlin()

j2k/src/org/jetbrains/jet/j2k/ast/MethodCallExpression.kt

@@ -18,20 +18,19 @@ package org.jetbrains.jet.j2k.ast
 
 import java.util.ArrayList
 
-open class MethodCallExpression(
+class MethodCallExpression(
         val methodExpression: Expression,
         val arguments: List<Expression>,
         val typeParameters: List<Type>,
-        val resultIsNullable: Boolean = false
+        override val isNullable: Boolean = false
 ) : Expression() {
 
-    override val isNullable: Boolean
-        get() = methodExpression.isNullable || resultIsNullable
-
     override fun toKotlin(): String {
-        val typeParamsToKotlin: String = typeParameters.toKotlin(", ", "<", ">")
-        val argumentsMapped = arguments.map { it.toKotlin() }
-        return operandToKotlin(methodExpression) + typeParamsToKotlin + "(" + argumentsMapped.makeString(", ") + ")"
+        return operandToKotlin(methodExpression) +
+                typeParameters.toKotlin(", ", "<", ">") +
+                "(" +
+                arguments.map { it.toKotlin() }.makeString(", ") +
+                ")"
     }
 
     class object {

j2k/tests/testData/ast/annotations/jetbrainsNotNull.kt

@@ -6,7 +6,7 @@ public class Test(str: String) {
     var myStr: String = "String2"
 
     public fun sout(str: String) {
-        System.out?.println(str)
+        System.out!!.println(str)
     }
 
     public fun dummy(str: String): String {

j2k/tests/testData/ast/annotations/jetbrainsNotNullChainExpr.kt

@@ -15,8 +15,8 @@ class Bar() {
 class Test() {
     public fun test(barNotNull: Bar, barNullable: Bar?) {
         barNotNull.fooNotNull.execute()
-        barNotNull.fooNullable?.execute()
-        barNullable?.fooNotNull?.execute()
-        barNullable?.fooNullable?.execute()
+        barNotNull.fooNullable!!.execute()
+        barNullable!!.fooNotNull.execute()
+        barNullable!!.fooNullable!!.execute()
     }
 }

j2k/tests/testData/ast/assignmentExpression/nullability-settings.kt

@@ -6,6 +6,6 @@ class Foo() {
     fun foo(o: BitSet?) {
         val o2: BitSet? = o
         val foo: Int = 0
-        foo = o2?.size()!!
+        foo = o2!!.size()
     }
 }

j2k/tests/testData/ast/callChainExpression/libraryMethodCallFromInstance-settings.kt

@@ -13,9 +13,9 @@ class User() {
     fun main() {
         val lib: Library = Library()
         lib.call()
-        lib.getString()?.isEmpty()
+        lib.getString()!!.isEmpty()
 
         Library().call()
-        Library().getString()?.isEmpty()
+        Library().getString()!!.isEmpty()
     }
 }

j2k/tests/testData/ast/issues/kt-824-isDir.kt

@@ -8,11 +8,11 @@ import java.io.File
 public class Test() {
     class object {
         public fun isDir(parent: File?): Boolean {
-            if (parent == null || !parent?.exists()!!) {
+            if (parent == null || !parent!!.exists()) {
                 return false
             }
             val result = true
-            if (parent?.isDirectory()!!) {
+            if (parent!!.isDirectory()) {
                 return true
             } else
                 return false

j2k/tests/testData/ast/kotlinApiAccess/CorrectFunNullabilityDetected.kt

@@ -2,6 +2,6 @@ import kotlinApi.*
 
 class A() {
     fun foo(t: KotlinTrait): Int {
-        return t.nullableFun()?.length()!! + t.notNullableFun().length()
+        return t.nullableFun()!!.length() + t.notNullableFun().length()
     }
 }

j2k/tests/testData/ast/kotlinApiAccess/CorrectNullabilityDetected.kt

@@ -2,6 +2,6 @@ import kotlinApi.*
 
 class A() {
     fun foo(c: KotlinClass): Int {
-        return c.nullableProperty?.length()!! + c.property.length() + KotlinClass.nullableStaticVar!! + KotlinClass.staticVar + KotlinClass.nullableStaticFun(1)!! + KotlinClass.staticFun(1) + nullableGlobalFunction("")?.length()!! + globalFunction("").length()
+        return c.nullableProperty!!.length() + c.property.length() + KotlinClass.nullableStaticVar!! + KotlinClass.staticVar + KotlinClass.nullableStaticFun(1)!! + KotlinClass.staticFun(1) + nullableGlobalFunction("")!!.length() + globalFunction("").length()
     }
 }

j2k/tests/testData/ast/nullability/NullableMethodDotAccess.kt

@@ -4,6 +4,6 @@ class C() {
     }
 
     fun foo(): Int {
-        return getString(true)?.length()!!
+        return getString(true)!!.length()
     }
-}
+}

j2k/tests/testData/ast/nullability/NullableVariableDotAccess.kt

@@ -1,5 +1,5 @@
 fun foo(s: String?, b: Boolean): Int {
     if (s == null) System.out.println("null")
-    if (b) return s?.length()!!
+    if (b) return s!!.length()
     return 10
 }

j2k/tests/testData/ast/prefixOperator/nullableIf.kt

@@ -1,3 +1,3 @@
 val s = null
-if (!s?.isEmpty()!!) {
+if (!s!!.isEmpty()) {
 }