Update class_extension example and tests

Author: rnkaufman

languages/tree-sitter-stack-graphs-java/src/stack-graphs.tsg

@@ -150,6 +150,13 @@ attribute node_symbol = node            => symbol = (source-text node), source_n
     edge @class.type -> ref
 }
 
+(class_declaration
+  superclass: (superclass
+    (generic_type
+      (type_identifier)) @superclass_name)) @class {
+    edge @superclass_name.lexical_scope -> @class.lexical_scope
+}
+
 
 (class_declaration (type_parameters)) @class {
   node @class.type_parameters
@@ -361,7 +368,7 @@ attribute node_symbol = node            => symbol = (source-text node), source_n
   type_parameters: (type_parameters
     (type_parameter
       (type_identifier) @type_identifier))
-  body:(_) @body) @this {
+  body: (_) @body) @this {
   node type_ident
   attr (type_ident) node_definition = @type_identifier
   edge @body.lexical_scope -> type_ident

languages/tree-sitter-stack-graphs-java/test/decl/class_extension.java

@@ -1,6 +1,22 @@
-class TestClass extends SecondTestClass {
-                        // ^ defined: 5
+class String {
+    public int length() {}
+};
+
+class HashMap<K, V> {
+    public Set<MapEntry<K, V>> entrySet() {}
+    //                  ^ defined: 5
+}
+
+class LRUCache<K, V>
+    extends HashMap<K, V> {
+    //      ^ defined: 5
+    //              ^ defined: 10
+    //                 ^ defined: 10
 }
 
-class SecondTestClass {
+class MyMap extends LRUCache<String, String> {
+    public int go() {
+        return this.entrySet().iterator().next().getKey().length();
+        //                                                 ^ defined: 2
+    }
 }