properly read/write int?

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JavaTypeTransformer.java

@@ -24,6 +24,7 @@ public class JavaTypeTransformer {
     private final JetStandardLibrary standardLibrary;
     private Map<String, JetType> primitiveTypesMap;
     private Map<String, JetType> classTypesMap;
+    private Map<String, ClassDescriptor> classDescriptorMap;
 
     public JavaTypeTransformer(JavaSemanticServices javaSemanticServices, JetStandardLibrary standardLibrary, JavaDescriptorResolver resolver) {
         this.javaSemanticServices = javaSemanticServices;
@@ -199,4 +200,21 @@ public class JavaTypeTransformer {
         }
         return classTypesMap;
     }
+    
+    public Map<String, ClassDescriptor> getPrimitiveWrappersClassDescriptorMap() {
+        if (classDescriptorMap == null) {
+            classDescriptorMap = new HashMap<String, ClassDescriptor>();
+            classDescriptorMap.put("java.lang.Byte", standardLibrary.getByte());
+            classDescriptorMap.put("java.lang.Short", standardLibrary.getShort());
+            classDescriptorMap.put("java.lang.Character", standardLibrary.getChar());
+            classDescriptorMap.put("java.lang.Integer", standardLibrary.getInt());
+            classDescriptorMap.put("java.lang.Long", standardLibrary.getLong());
+            classDescriptorMap.put("java.lang.Float", standardLibrary.getFloat());
+            classDescriptorMap.put("java.lang.Double", standardLibrary.getDouble());
+            classDescriptorMap.put("java.lang.Boolean", standardLibrary.getBoolean());
+            //classDescriptorMap.put("java.lang.Object", standardLibrary.get
+            classDescriptorMap.put("java.lang.String", standardLibrary.getString());
+        }
+        return classDescriptorMap;
+    }
 }

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/java/JetTypeJetSignatureReader.java

@@ -96,7 +96,13 @@ public abstract class JetTypeJetSignatureReader extends JetSignatureExceptionsAd
     @Override
     public void visitClassType(String name, boolean nullable) {
         String ourName = name.replace('/', '.');
-        this.classDescriptor = javaDescriptorResolver.resolveClass(ourName);
+        
+        this.classDescriptor = this.javaSemanticServices.getTypeTransformer().getPrimitiveWrappersClassDescriptorMap().get(ourName);
+
+        if (this.classDescriptor == null) {
+            this.classDescriptor = javaDescriptorResolver.resolveClass(ourName);
+        }
+
         if (this.classDescriptor == null) {
             throw new IllegalStateException("class not found by name: " + ourName); // TODO: wrong exception
         }

compiler/testData/readClass/type/Int.kt

@@ -0,0 +1,3 @@
+package test
+
+fun fff(): Int = 1

compiler/testData/readClass/type/IntQ.kt

@@ -0,0 +1,3 @@
+package test
+
+fun fff(): Int? = 1

compiler/tests/org/jetbrains/jet/WriteSignatureTest.java

@@ -210,8 +210,8 @@ public class WriteSignatureTest extends TestCaseWithTmpdir {
             new ClassReader(classInputStream).accept(visitor,
                     ClassReader.SKIP_CODE|ClassReader.SKIP_DEBUG|ClassReader.SKIP_FRAMES);
             
-            Assert.assertNotNull(visitor.readSignature);
-            
+            Assert.assertNotNull("method not found: " + className + "::" + methodName, visitor.readSignature);
+
             return visitor.readSignature;
         } finally {
             Closeables.closeQuietly(classInputStream);