Minor, refactor FileBasedKotlinClass factory method

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/kotlin/FileBasedKotlinClass.java

@@ -16,8 +16,8 @@
 
 package org.jetbrains.jet.lang.resolve.kotlin;
 
-import com.intellij.openapi.util.Pair;
 import com.intellij.openapi.util.Ref;
+import kotlin.Function2;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.resolve.java.JvmClassName;
@@ -45,7 +45,10 @@ public abstract class FileBasedKotlinClass implements KotlinJvmBinaryClass {
     protected abstract byte[] getFileContents();
 
     @Nullable
-    public static Pair<JvmClassName, KotlinClassHeader> readClassNameAndHeader(@NotNull byte[] fileContents) {
+    protected static <T extends FileBasedKotlinClass> T create(
+            @NotNull byte[] fileContents,
+            @NotNull Function2<JvmClassName, KotlinClassHeader, T> factory
+    ) {
         final ReadKotlinClassHeaderAnnotationVisitor readHeaderVisitor = new ReadKotlinClassHeaderAnnotationVisitor();
         final Ref<JvmClassName> classNameRef = Ref.create();
         new ClassReader(fileContents).accept(new ClassVisitor(ASM5) {
@@ -71,7 +74,7 @@ public abstract class FileBasedKotlinClass implements KotlinJvmBinaryClass {
         KotlinClassHeader header = readHeaderVisitor.createHeader();
         if (header == null) return null;
 
-        return Pair.create(className, header);
+        return factory.invoke(className, header);
     }
 
     @NotNull

compiler/frontend.java/src/org/jetbrains/jet/lang/resolve/kotlin/VirtualFileKotlinClass.java

@@ -18,8 +18,8 @@ package org.jetbrains.jet.lang.resolve.kotlin;
 
 import com.intellij.ide.highlighter.JavaClassFileType;
 import com.intellij.openapi.diagnostic.Logger;
-import com.intellij.openapi.util.Pair;
 import com.intellij.openapi.vfs.VirtualFile;
+import kotlin.Function2;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.jet.lang.resolve.java.JvmClassName;
@@ -39,14 +39,15 @@ public final class VirtualFileKotlinClass extends FileBasedKotlinClass {
     }
 
     @Nullable
-    /* package */ static VirtualFileKotlinClass create(@NotNull VirtualFile file) {
+    /* package */ static VirtualFileKotlinClass create(@NotNull final VirtualFile file) {
         assert file.getFileType() == JavaClassFileType.INSTANCE : "Trying to read binary data from a non-class file " + file;
         try {
-            byte[] fileContents = file.contentsToByteArray();
+            return create(file.contentsToByteArray(), new Function2<JvmClassName, KotlinClassHeader, VirtualFileKotlinClass>() {
-            Pair<JvmClassName, KotlinClassHeader> nameAndHeader = readClassNameAndHeader(fileContents);
+                @Override
-            if (nameAndHeader == null) return null;
+                public VirtualFileKotlinClass invoke(JvmClassName name, KotlinClassHeader header) {
-
+                    return new VirtualFileKotlinClass(file, name, header);
-            return new VirtualFileKotlinClass(file, nameAndHeader.first, nameAndHeader.second);
+                }
+            });
         }
         catch (Throwable e) {
             LOG.warn(renderFileReadingErrorMessage(file));

jps-plugin/src/org/jetbrains/jet/jps/incremental/LocalFileKotlinClass.kt

@@ -31,10 +31,10 @@ class LocalFileKotlinClass private(
     class object {
         fun create(file: File): LocalFileKotlinClass? {
             val fileContents = file.readBytes()
-            val nameAndHeader = FileBasedKotlinClass.readClassNameAndHeader(fileContents)
+            return FileBasedKotlinClass.create(fileContents) {
-            if (nameAndHeader == null) return null
+                className, classHeader ->
-
+                LocalFileKotlinClass(file, fileContents, className, classHeader)
-            return LocalFileKotlinClass(file, fileContents, nameAndHeader.first!!, nameAndHeader.second!!)
+            }
         }
     }