5041784: (reflect) generic signature methods needlessly return generic arrays
authoremcmanus
Wed, 27 Aug 2008 11:03:59 +0200
changeset 1144 7a9035ddf8e2
parent 1143 645d4b930f93
child 1145 404b11752c57
5041784: (reflect) generic signature methods needlessly return generic arrays Reviewed-by: darcy
jdk/src/share/classes/sun/reflect/generics/factory/CoreReflectionFactory.java
jdk/test/java/lang/reflect/Generics/TestPlainArrayNotGeneric.java
--- a/jdk/src/share/classes/sun/reflect/generics/factory/CoreReflectionFactory.java	Tue Aug 26 10:21:22 2008 +0100
+++ b/jdk/src/share/classes/sun/reflect/generics/factory/CoreReflectionFactory.java	Wed Aug 27 11:03:59 2008 +0200
@@ -25,6 +25,7 @@
 
 package sun.reflect.generics.factory;
 
+import java.lang.reflect.Array;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.GenericDeclaration;
 import java.lang.reflect.Method;
@@ -118,7 +119,10 @@
     }
 
     public Type makeArrayType(Type componentType){
-        return GenericArrayTypeImpl.make(componentType);
+        if (componentType instanceof Class<?>)
+            return Array.newInstance((Class<?>) componentType, 0).getClass();
+        else
+            return GenericArrayTypeImpl.make(componentType);
     }
 
     public Type makeByte(){return byte.class;}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/reflect/Generics/TestPlainArrayNotGeneric.java	Wed Aug 27 11:03:59 2008 +0200
@@ -0,0 +1,156 @@
+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 5041784
+ * @summary Check that plain arrays like String[] are never represented as
+ * GenericArrayType.
+ * @author Eamonn McManus
+ */
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.GenericArrayType;
+import java.lang.reflect.GenericDeclaration;
+import java.lang.reflect.Method;
+import java.lang.reflect.ParameterizedType;
+import java.lang.reflect.Type;
+import java.lang.reflect.TypeVariable;
+import java.lang.reflect.WildcardType;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+public class TestPlainArrayNotGeneric {
+    public String[] m1(List<String> p1) {return null;}
+    public List<String> m2(String[] p1) {return null;}
+    public void m3(List<String> p1, String[] p2) {}
+    public void m4(List<String[]> p1) {}
+    public TestPlainArrayNotGeneric(List<String[]> p1) {}
+    public TestPlainArrayNotGeneric(List<String> p1, String[] p2) {}
+
+    public <T extends List<String[]>> T m5(T p1) {return null;}
+    public <T extends Object> T[] m6(T[] p1, List<T[]> p2) {return null;}
+
+    public List<? extends Object[]> m6(List<? extends Object[]> p1) {return null;}
+    public <T extends List<? extends Object[]>> T m7(T[] p1) {return null;}
+    public List<? super Object[]> m8(List<? super Object[]> p1) {return null;}
+    public <T extends List<? super Object[]>> T[] m9(T[] p1) {return null;}
+
+    public static interface XMap extends Map<List<String[]>, String[]> {}
+    public static interface YMap<K extends List<String[]>, V>
+            extends Map<K[], V[]> {}
+
+
+    private static String lastFailure;
+    private static int failureCount;
+
+    public static void main(String[] args) throws Exception {
+        checkClass(TestPlainArrayNotGeneric.class);
+
+        if (failureCount == 0)
+            System.out.println("TEST PASSED");
+        else
+            throw new Exception("TEST FAILED: Last failure: " + lastFailure);
+    }
+
+    private static void checkClass(Class<?> c) throws Exception {
+        Method[] methods = c.getMethods();
+        for (Method m : methods) {
+            check(m.getGenericReturnType(), "return type of method " + m);
+            check(m.getGenericParameterTypes(), "parameter", "method " + m);
+            check(m.getTypeParameters(), "type parameter", "method " + m);
+        }
+
+        Constructor[] constructors = c.getConstructors();
+        for (Constructor constr : constructors) {
+            check(constr.getGenericParameterTypes(), "parameter",
+                    "constructor " + constr);
+            check(constr.getTypeParameters(), "type parameter",
+                    "constructor " + constr);
+        }
+
+        Class<?>[] inners = c.getDeclaredClasses();
+        for (Class inner : inners)
+            checkClass(inner);
+    }
+
+    private static void check(Type[] types, String elementKind, String what) {
+        for (int i = 0; i < types.length; i++) {
+            Type t = types[i];
+            check(t, elementKind + " " + (i+1) + " of " + what);
+        }
+    }
+
+    private static final Set<Type> checking = new HashSet<Type>();
+
+    private static void check(Type t, String what) {
+        if (t == null || !checking.add(t))
+            return;
+        // Avoid infinite recursion.  t can be null e.g. for superclass of Object.
+        try {
+            check2(t, what);
+        } finally {
+            checking.remove(t);
+        }
+    }
+
+    private static void check2(Type t, String what) {
+        if (t instanceof ParameterizedType) {
+            ParameterizedType pt = (ParameterizedType) t;
+            check(pt.getActualTypeArguments(), "type argument", what);
+        } else if (t instanceof TypeVariable) {
+            TypeVariable<?> tv = (TypeVariable<?>) t;
+            check(tv.getBounds(), "bound", what);
+            GenericDeclaration gd = tv.getGenericDeclaration();
+            if (gd instanceof Type)
+                check((Type) gd, "declaration containing " + what);
+        } else if (t instanceof WildcardType) {
+            WildcardType wt = (WildcardType) t;
+            check(wt.getLowerBounds(), "lower bound", "wildcard type in " + what);
+            check(wt.getUpperBounds(), "upper bound", "wildcard type in " + what);
+        } else if (t instanceof Class<?>) {
+            Class<?> c = (Class<?>) t;
+            check(c.getGenericInterfaces(), "superinterface", c.toString());
+            check(c.getGenericSuperclass(), "superclass of " + c);
+            check(c.getTypeParameters(), "type parameter", c.toString());
+        } else if (t instanceof GenericArrayType) {
+            GenericArrayType gat = (GenericArrayType) t;
+            Type comp = gat.getGenericComponentType();
+            if (comp instanceof Class) {
+                fail("Type " + t + " uses GenericArrayType when plain " +
+                        "array would do, in " + what);
+            } else
+                check(comp, "component type of " + what);
+        } else {
+            fail("TEST BUG: mutant Type " + t + " (a " + t.getClass().getName() + ")");
+        }
+    }
+
+    private static void fail(String why) {
+        System.out.println("FAIL: " + why);
+        lastFailure = why;
+        failureCount++;
+    }
+}