Fixed JERSEY-2946: StackOverFlowError in Resource.Builder.toString().

Change-Id: Ia94cedd8b5355496a741976f3a40600922a20f3c

Author: Marek Potociar

core-server/src/main/java/org/glassfish/jersey/server/model/Resource.java

@@ -171,7 +171,7 @@ private Data(
 
             this.extended = extended;
 
-            this.names = immutableCopy(names);
+            this.names = Resource.immutableCopy(names);
             this.path = path;
             this.pathPattern = (path == null || path.isEmpty())
                     ? PathPattern.OPEN_ROOT_PATH_PATTERN
@@ -578,6 +578,7 @@ private List<Resource.Data> mergeResources(List<Resource.Data> resources) {
                         }
                         builder.mergeWith(inner);
                         resources.remove(j);
+                        //noinspection AssignmentToForLoopParameter
                         j--;
                     }
                 }
@@ -683,10 +684,14 @@ public String toString() {
                     + ", subResourceLocator=" + subResourceLocator
                     + ", handlerClasses=" + handlerClasses
                     + ", handlerInstances=" + handlerInstances
-                    + ", parentResource=" + parentResource
+                    + ", parentResource=" + ((parentResource == null) ? "<no parent>" : parentResource.shortToString())
                     + ", extended=" + extended
                     + '}';
         }
+
+        private String shortToString() {
+            return "Builder{names=" + names + ", path='" + path + "'}";
+        }
     }
 
     /**
@@ -1056,7 +1061,7 @@ public String toString() {
 
     @Override
     public List<? extends ResourceModelComponent> getComponents() {
-        List<ResourceModelComponent> components = new LinkedList<ResourceModelComponent>();
+        List<ResourceModelComponent> components = new LinkedList<>();
 
         components.addAll(getChildResources());
         components.addAll(getResourceMethods());

core-server/src/test/java/org/glassfish/jersey/server/model/ResourceModelTest.java

@@ -51,6 +51,7 @@
 
 import org.junit.Test;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.fail;
 
 import jersey.repackaged.com.google.common.collect.Lists;
@@ -183,6 +184,20 @@ public void testResourceModel() {
                 "another-child"), false, "PUT");
     }
 
+    /**
+     * Reproducer for JERSEY-2946: StackOverFlowError in Resource.toString()
+     */
+    @Test
+    public void testResourceWithChildrenDoesNotOverflowToString() {
+        final Resource.Builder parentBuilder = Resource.builder("parent");
+        final Resource.Builder childBuilder = parentBuilder.addChildResource("child");
+        final Resource.Builder locatorBuilder = parentBuilder.addChildResource("child");
+
+        // In Jersey 2.21 this throws StackOverFlowError.
+        assertNotNull(childBuilder.toString());
+        assertNotNull(parentBuilder.toString());
+    }
+
     @Test
     public void testRuntimeResourceModel() {
         ResourceModel resourceModel = getResourceModel();