ObjectLayout · simonis · Nov 11, 2014 · Dec 11, 2014
diff --git a/ObjectLayout/pom.xml b/ObjectLayout/pom.xml
@@ -65,7 +65,7 @@
                 <artifactId>maven-surefire-plugin</artifactId>
                 <version>2.12.4</version>
                 <configuration>
-                    <argLine>-Xmx1g</argLine>
+                    <argLine>-Xmx1g -Xbootclasspath/a:${basedir}/target/classes</argLine>
                     <enableAssertions>false</enableAssertions>
                 </configuration>
             </plugin>

diff --git a/ObjectLayout/src/main/java/org/ObjectLayout/AbstractIntrinsicObjectModel.java b/ObjectLayout/src/main/java/org/ObjectLayout/AbstractIntrinsicObjectModel.java
@@ -45,6 +45,14 @@ Class<T> getObjectClass() {
         return objectClass;
     }
 
+    Class<T> getContainingClass() {
+        return containingClass;
+    }
+
+    Field getField() {
+        return field;
+    }
+
     private void sanityCheckAtModelConstruction() {
         if ((primitiveArrayModel != null) &&
                 !primitiveArrayModel._getArrayClass().equals(objectClass)) {
@@ -141,7 +149,8 @@ final void _sanityCheckInstantiation(final Object containingObject) {
         try {
             if (field.get(containingObject) != null) {
                 throw new IllegalStateException("Intrinsic object field \"" + field.getName() +
-                        "\" in containing object is already initialized");
+                        "\" in containing object " + containingObject + " is already initialized to " +
+                        field.get(containingObject));
             }
         } catch (IllegalAccessException e) {
             throw new IllegalStateException(e);

diff --git a/ObjectLayout/src/main/java/org/ObjectLayout/IntrinsicObjectModel.java b/ObjectLayout/src/main/java/org/ObjectLayout/IntrinsicObjectModel.java
@@ -34,9 +34,13 @@ final class IntrinsicObjectModel<T> extends AbstractIntrinsicObjectModel<T> {
      */
     final T constructWithin(final Object containingObject) {
         try {
+            Constructor<T> ctor = getObjectClass().getDeclaredConstructor();
+            if (!ctor.isAccessible()) {
+                ctor.setAccessible(true);
+            }
             return instantiate(
                     containingObject,
-                    getObjectClass().getDeclaredConstructor(),
+                    ctor,
                     (Object[]) null
             );
         } catch (NoSuchMethodException ex) {

diff --git a/ObjectLayout/src/main/java/org/ObjectLayout/IntrinsicObjects.java b/ObjectLayout/src/main/java/org/ObjectLayout/IntrinsicObjects.java
@@ -12,6 +12,9 @@
 import java.util.HashMap;
 import java.util.concurrent.ConcurrentHashMap;
 
+import sun.reflect.CallerSensitive;
+import sun.reflect.Reflection;
+
 /**
  * Intrinsic objects (declared with the {@link org.ObjectLayout.Intrinsic @Intrisic} annotation) may have
  * their layout within the containing object instance optimized by JDK implementations, such that access
@@ -55,10 +58,24 @@ private IntrinsicObjects() {
      * @param containingObject The object instance that will contain this intrinsic object
      * @return A reference to the the newly constructed intrinsic object
      */
+    @CallerSensitive
+    @SuppressWarnings("restriction")
     public static <T> T constructWithin(
             final String fieldName,
-            final Object containingObject) {
+            final Object containingObject) throws IllegalArgumentException {
+
+        // First we do some plausibility/security checks
+        Class<?> caller = Reflection.getCallerClass();
+        if (!containingObject.getClass().equals(caller))
+            throw new IllegalArgumentException();
+
         IntrinsicObjectModel<T> model = lookupModelFor(fieldName, containingObject);
+
+        // Check if our caller is allowed to access the constructor.
+        // We wrap the "IllegalAccessException" in an unchecked "IllegalArgumentException"
+        // to avoid try/catch clauses around every call to "constructWithin"
+        sanityCheckAccessRights(caller, model.getObjectClass(), null);
+
         return model.constructWithin(containingObject);
     }
 
@@ -75,12 +92,26 @@ public static <T> T constructWithin(
      * @param args the arguments to be used with the objectConstructor
      * @return A reference to the the newly constructed intrinsic object
      */
+    @CallerSensitive
+    @SuppressWarnings("restriction")
     public static <T> T constructWithin(
             final String fieldName,
             final Object containingObject,
             final Constructor<T> objectConstructor,
             final Object... args) {
+
+        // First we do some plausibility/security checks
+        Class<?> caller = Reflection.getCallerClass();
+        if (!containingObject.getClass().equals(caller))
+            throw new IllegalArgumentException();
+
         IntrinsicObjectModel<T> model = lookupModelFor(fieldName, containingObject);
+
+        // Check if our caller is allowed to access the constructor.
+        // We wrap the "IllegalAccessException" in an unchecked "IllegalArgumentException"
+        // to avoid try/catch clauses around every call to "constructWithin"
+        sanityCheckAccessRights(caller, model.getObjectClass(), objectConstructor);
+
         return model.constructWithin(containingObject, objectConstructor, args);
     }
 
@@ -339,4 +370,20 @@ private static <T> void sanityCheckAnnotation(Intrinsic intrinsicAnnotation, Cla
             }
         }
     }
+
+    @SuppressWarnings("restriction")
+    private static <T> void sanityCheckAccessRights(Class<?> caller, Class<T> field, Constructor<T> ctor) {
+        // Check if our caller is allowed to access the constructor.
+        // We wrap the "IllegalAccessException" in an unchecked "IllegalArgumentException"
+        // to avoid try/catch clauses around every call to "constructWithin"
+        try {
+            if (ctor == null)
+                ctor = field.getDeclaredConstructor();
+            Reflection.ensureMemberAccess(caller, field, ctor, ctor.getModifiers());
+        } catch (IllegalAccessException e) {
+            throw new IllegalArgumentException(e);
+        } catch (NoSuchMethodException e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
 }