Skip completely inaccessible classpath elements in package caching

Author: HannesWell

org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/AccessRestrictionsTests.java

@@ -1108,28 +1108,13 @@ public void test011() throws CoreException {
 			"----------\n" +
 			"1. ERROR in /P1/src/q/Y.java (at line 4)\n" +
 			"	p.X x = new p.X();\n" +
-			"	^^^\n" +
-			"Access restriction: The type \'X\' is not accessible (restriction on required library \'AccessRestrictions/lib.jar\')\n" +
+			"	^\n" +
+			"p cannot be resolved to a type\n" +
 			"----------\n" +
 			"2. ERROR in /P1/src/q/Y.java (at line 4)\n" +
 			"	p.X x = new p.X();\n" +
-			"	            ^^^\n" +
-			"Access restriction: The type \'X\' is not accessible (restriction on required library \'AccessRestrictions/lib.jar\')\n" +
-			"----------\n" +
-			"3. ERROR in /P1/src/q/Y.java (at line 4)\n" +
-			"	p.X x = new p.X();\n" +
-			"	            ^^^\n" +
-			"Access restriction: The constructor \'X()\' is not accessible (restriction on required library \'AccessRestrictions/lib.jar\')\n" +
-			"----------\n" +
-			"4. ERROR in /P1/src/q/Y.java (at line 5)\n" +
-			"	x.foo();\n" +
-			"	  ^^^\n" +
-			"Access restriction: The method \'X.foo()\' is not accessible (restriction on required library \'AccessRestrictions/lib.jar\')\n" +
-			"----------\n" +
-			"5. ERROR in /P1/src/q/Y.java (at line 6)\n" +
-			"	if (x.m > 0) {}\n" +
-			"	      ^\n" +
-			"Access restriction: The field \'X.m\' is not accessible (restriction on required library \'AccessRestrictions/lib.jar\')\n" +
+			"	            ^\n" +
+			"p cannot be resolved to a type\n" +
 			"----------\n"
 		);
 	} finally {

org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/NameLookupTests2.java

@@ -455,8 +455,7 @@ public class A {}
 				true /* wait for indexer */,
 				true /* check restrictions */,
 				null);
-		assertNotNull("Expected to find type", answer);
-		assertTrue("Expected type to be non-accessible", answer.isNonAccessible());
+		assertNull("Expected to not find type", answer);
 	} finally {
 		deleteProject("P");
 	}

org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/JavaProjectElementInfo.java

@@ -13,6 +13,7 @@
  *******************************************************************************/
 package org.eclipse.jdt.internal.core;
 
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 import org.eclipse.core.resources.IContainer;
@@ -26,6 +27,9 @@
 import org.eclipse.jdt.core.IPackageFragmentRoot;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.core.JavaModelException;
+import org.eclipse.jdt.core.compiler.IProblem;
+import org.eclipse.jdt.internal.compiler.env.AccessRule;
+import org.eclipse.jdt.internal.compiler.env.AccessRuleSet;
 import org.eclipse.jdt.internal.core.DeltaProcessor.RootInfo;
 import org.eclipse.jdt.internal.core.util.HashSetOfArray;
 import org.eclipse.jdt.internal.core.util.HashtableOfArrayToObject;
@@ -240,7 +244,10 @@ ProjectCache getProjectCache(JavaProject project, boolean excludeTestCode) {
 					roots[i] = root = (IPackageFragmentRoot) manager.getExistingElement(root);
 					// compute fragment cache
 					HashSetOfArray fragmentsCache = new HashSetOfArray();
-					initializePackageNames(root, fragmentsCache);
+					if (!(reverseMap.get(root) instanceof ClasspathEntry cpEntry)
+							|| !isCompletelyNonAccessible(cpEntry)) {
+						initializePackageNames(root, fragmentsCache);
+					}
 					pkgFragmentsCaches.put(root, fragmentsCache);
 				}
 			}
@@ -255,6 +262,22 @@ ProjectCache getProjectCache(JavaProject project, boolean excludeTestCode) {
 		return cache;
 	}
 
+	private static final char[] ALL_ELEMENTS = {'*', '*', '/', '*'};
+
+	private boolean isCompletelyNonAccessible(ClasspathEntry cpEntry) {
+		AccessRuleSet accessRules = cpEntry.getAccessRuleSet();
+		if (accessRules != null) {
+			AccessRule[] rules = accessRules.getAccessRules();
+			if (rules.length == 1) {
+				AccessRule rule = rules[0];
+				if (rule.getProblemId() == IProblem.ForbiddenReference && Arrays.equals(ALL_ELEMENTS, rule.pattern)) {
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+
 	/**
 	 * Returns an array of non-java resources contained in the receiver.
 	 */