diff --git a/compiler/testData/codegen/regressions/kt344.jet b/compiler/testData/codegen/regressions/kt344.jet
index 1f35cb5e138..99f657592e1 100644
--- a/compiler/testData/codegen/regressions/kt344.jet
+++ b/compiler/testData/codegen/regressions/kt344.jet
@@ -186,8 +186,8 @@ fun box(): String {
     if (!t8()) return "t8 fail"
     if (!t9(0)) return "t9 fail"
     if (!t10()) return "t10 fail"
-    if (t11(1) != 104) return "t11 fail"
+    if (t11(1) != 101) return "t11 fail"
     if (t12(0) != 100) return "t12 fail"
 
     return "OK"
-}
\ No newline at end of file
+}
diff --git a/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java b/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
index 312db145222..4343c8a8991 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/CodegenTestCase.java
@@ -133,20 +133,7 @@ public abstract class CodegenTestCase extends UsefulTestCase {
 
     protected void blackBoxFile(String filename) {
         loadFile(filename);
-        Object actual;
-        try {
-            actual = blackBox();
-        } catch (NoClassDefFoundError e) {
-            System.out.println(generateToText());
-            throw e;
-        } catch (Throwable e) {
-            System.out.println(generateToText());
-            throw new RuntimeException(e);
-        }
-        if (!Objects.equal(myFile.getExpectedValue(), actual)) {
-            System.out.println(generateToText());
-        }
-        assertEquals(myFile.getExpectedValue(), actual);
+        blackBox();
     }
 
     @NotNull
@@ -188,11 +175,12 @@ public abstract class CodegenTestCase extends UsefulTestCase {
         }
     }
 
-    @NotNull
-    protected String blackBox() throws Exception {
+    protected void blackBox() {
         GenerationState state = generateClassesInFileGetState();
         GeneratedClassLoader loader = createClassLoader(state.getFactory());
 
+        String r;
+
         try {
             if (myFile.getPsiFile().isScript()) {
                 Class<?> scriptClass = loader.loadClass("Script");
@@ -202,23 +190,38 @@ public abstract class CodegenTestCase extends UsefulTestCase {
                 Field field = scriptClass.getDeclaredField("rv");
                 field.setAccessible(true);
                 Object result = field.get(scriptInstance);
-                return result != null ? result.toString() : "null";
+                r = result != null ? result.toString() : "null";
             }
             else {
                 String fqName = NamespaceCodegen.getJVMClassNameForKotlinNs(JetPsiUtil.getFQName(myFile.getPsiFile())).getFqName().getFqName();
                 Class<?> namespaceClass = loader.loadClass(fqName);
                 Method method = namespaceClass.getMethod("box");
-                return (String) method.invoke(null);
+                r = (String) method.invoke(null);
             }
+        } catch (NoClassDefFoundError e) {
+            System.out.println(generateToText());
+            throw e;
+        } catch (Throwable e) {
+            System.out.println(generateToText());
+            throw new RuntimeException(e);
         } finally {
-           loader.dispose();
+            loader.dispose();
         }
+
+        if (!Objects.equal(myFile.getExpectedValue(), r)) {
+            System.out.println(generateToText());
+        }
+        assertEquals(myFile.getExpectedValue(), r);
     }
 
-    protected GeneratedClassLoader createClassLoader(ClassFileFactory codegens) throws MalformedURLException {
+    protected GeneratedClassLoader createClassLoader(ClassFileFactory codegens) {
         List<URL> urls = Lists.newArrayList();
         for (File file : extraClasspath) {
-            urls.add(file.toURI().toURL());
+            try {
+                urls.add(file.toURI().toURL());
+            } catch (MalformedURLException e) {
+                throw new RuntimeException(e);
+            }
         }
         ClassLoader parentClassLoader = new URLClassLoader(urls.toArray(new URL[0]), CodegenTestCase.class.getClassLoader());
         return new GeneratedClassLoader(codegens, parentClassLoader);
@@ -255,8 +258,6 @@ public abstract class CodegenTestCase extends UsefulTestCase {
             return createClassLoader(state).loadClass(fqName);
         } catch (ClassNotFoundException e) {
             e.printStackTrace();
-        } catch (MalformedURLException e) {
-            e.printStackTrace();
         }
         return null;
     }
@@ -265,7 +266,6 @@ public abstract class CodegenTestCase extends UsefulTestCase {
         try {
             return createClassLoader(state).loadClass(fqName);
         } catch (ClassNotFoundException e) {
-        } catch (MalformedURLException e) {
         }
 
         fail("No classfile was generated for: " + fqName);
diff --git a/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java b/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
index 50700c26205..7e587af3167 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java
@@ -337,7 +337,7 @@ public class PrimitiveTypesTest extends CodegenTestCase {
 
     public void testKt737() throws Exception {
         loadText("fun box() = if(3.compareTo(2) != 1) \"fail\" else if(5.toByte().compareTo(10.toLong()) >= 0) \"fail\" else \"OK\"");
-        assertEquals("OK", blackBox());
+        blackBox();
     }
 
     public void testKt665() throws Exception {
diff --git a/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java b/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
index d2015cb0f0a..3b4a8c9c151 100644
--- a/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
+++ b/compiler/tests/org/jetbrains/jet/codegen/StdlibTest.java
@@ -47,11 +47,15 @@ public class StdlibTest extends CodegenTestCase {
     }
 
     @Override
-    protected GeneratedClassLoader createClassLoader(ClassFileFactory codegens) throws MalformedURLException {
-        return new GeneratedClassLoader(
-                codegens,
-                new URLClassLoader(new URL[]{ForTestCompileRuntime.runtimeJarForTests().toURI().toURL()},
-                                   getClass().getClassLoader()));
+    protected GeneratedClassLoader createClassLoader(ClassFileFactory codegens) {
+        try {
+            return new GeneratedClassLoader(
+                    codegens,
+                    new URLClassLoader(new URL[]{ForTestCompileRuntime.runtimeJarForTests().toURI().toURL()},
+                                       getClass().getClassLoader()));
+        } catch (MalformedURLException e) {
+            throw new RuntimeException(e);
+        }
     }
 
     public void testKt533 () {