--- a/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Resolve.java	Tue Mar 15 13:48:30 2016 -0700
+++ b/langtools/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Resolve.java	Thu Mar 17 19:04:28 2016 +0000
@@ -93,10 +93,13 @@
     JCDiagnostic.Factory diags;
     public final boolean allowMethodHandles;
     public final boolean allowFunctionalInterfaceMostSpecific;
+    public final boolean allowModules;
     public final boolean checkVarargsAccessAfterResolution;
     private final boolean compactMethodDiags;
     final EnumSet<VerboseResolutionMode> verboseResolutionMode;
 
+    private final boolean checkModuleAccess;
+
     WriteableScope polymorphicSignatureScope;
 
     protected Resolve(Context context) {
@@ -130,6 +133,12 @@
         polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
 
         inapplicableMethodException = new InapplicableMethodException(diags);
+
+        allowModules = source.allowModules();
+
+        // The following is required, for now, to support building
+        // Swing beaninfo via javadoc.
+        checkModuleAccess = !options.isSet("noModules");
     }
 
     /** error symbols, which are returned when resolution fails
@@ -309,8 +318,19 @@
                     env.toplevel.packge == c.packge();
                 break;
             default: // error recovery
+                isAccessible = true;
+                break;
             case PUBLIC:
                 isAccessible = true;
+                if (allowModules && checkModuleAccess) {
+                    ModuleSymbol currModule = env.toplevel.modle;
+                    currModule.complete();
+                    PackageSymbol p = c.packge();
+                    isAccessible =
+                        (currModule == p.modle) || currModule.visiblePackages.get(p.fullname) == p || p == syms.rootPackage;
+                } else {
+                    isAccessible = true;
+                }
                 break;
             case PROTECTED:
                 isAccessible =
@@ -1947,16 +1967,27 @@
      */
     Symbol loadClass(Env<AttrContext> env, Name name) {
         try {
-            ClassSymbol c = finder.loadClass(name);
+            ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
             return isAccessible(env, c) ? c : new AccessError(c);
         } catch (ClassFinder.BadClassFile err) {
             throw err;
         } catch (CompletionFailure ex) {
+            //even if a class cannot be found in the current module and packages in modules it depends on that
+            //are exported for any or this module, the class may exist internally in some of these modules,
+            //or may exist in a module on which this module does not depend. Provide better diagnostic in
+            //such cases by looking for the class in any module:
+            for (ModuleSymbol ms : syms.getAllModules()) {
+                //do not load currently unloaded classes, to avoid too eager completion of random things in other modules:
+                ClassSymbol clazz = syms.getClass(ms, name);
+
+                if (clazz != null) {
+                    return new AccessError(clazz);
+                }
+            }
             return typeNotFound;
         }
     }
 
-
     /**
      * Find a type declared in a scope (not inherited).  Return null
      * if none is found.
@@ -2157,7 +2188,7 @@
         }
 
         if (kind.contains(KindSelector.PCK))
-            return syms.enterPackage(name);
+            return syms.lookupPackage(env.toplevel.modle, name);
         else return bestSoFar;
     }
 
@@ -2173,7 +2204,7 @@
         Symbol bestSoFar = typeNotFound;
         PackageSymbol pack = null;
         if (kind.contains(KindSelector.PCK)) {
-            pack = syms.enterPackage(fullname);
+            pack = syms.lookupPackage(env.toplevel.modle, fullname);
             if (pack.exists()) return pack;
         }
         if (kind.contains(KindSelector.TYP)) {
@@ -3920,9 +3951,15 @@
             else if ((sym.flags() & PUBLIC) != 0
                 || (env != null && this.site != null
                     && !isAccessible(env, this.site))) {
-                return diags.create(dkind, log.currentSource(),
-                        pos, "not.def.access.class.intf.cant.access",
-                    sym, sym.location());
+                if (sym.owner.kind == PCK) {
+                    return diags.create(dkind, log.currentSource(),
+                            pos, "not.def.access.package.cant.access",
+                        sym, sym.location());
+                } else {
+                    return diags.create(dkind, log.currentSource(),
+                            pos, "not.def.access.class.intf.cant.access",
+                        sym, sym.location());
+                }
             }
             else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
                 return diags.create(dkind, log.currentSource(),
@@ -3935,6 +3972,18 @@
                         pos, "not.def.public.cant.access", sym, sym.location());
             }
         }
+
+        private String toString(Type type) {
+            StringBuilder sb = new StringBuilder();
+            sb.append(type);
+            if (type != null) {
+                sb.append("[tsym:").append(type.tsym);
+                if (type.tsym != null)
+                    sb.append("packge:").append(type.tsym.packge());
+                sb.append("]");
+            }
+            return sb.toString();
+        }
     }
 
     /**