Fix ProxyBuilder tries to extend final methods.

If an interface method is implemented by a final method in a parent
class of the interface-implementng child, ProxyBuilder misses the
final'ness of the implementation, and tries to override the method.V

(cherry picked from commit 6ada76ae1356c9d05e6e4f4a4ae02c914e634534)
BUG: 27342578

Change-Id: Ic7c05c90c98469114fff1fc3f0eab28aa43ebff4

2 files changed, 19 insertions, 1 deletions

diff --git a/src/main/java/com/google/dexmaker/stock/ProxyBuilder.java b/src/main/java/com/google/dexmaker/stock/ProxyBuilder.java
index f943840..aa59886 100644
--- a/src/main/java/com/google/dexmaker/stock/ProxyBuilder.java
+++ b/src/main/java/com/google/dexmaker/stock/ProxyBuilder.java
@@ -634,7 +634,11 @@ public final class ProxyBuilder<T> {
                 // Skip final methods, we can't override them. We
                 // also need to remember them, in case the same
                 // method exists in a parent class.
-                seenFinalMethods.add(new MethodSetEntry(method));
+                MethodSetEntry entry = new MethodSetEntry(method);
+                seenFinalMethods.add(entry);
+                // We may have seen this method already, from an interface
+                // implemented by a child class. We need to remove it here.
+                sink.remove(entry);
                 continue;
             }
             if ((method.getModifiers() & STATIC) != 0) {
diff --git a/src/test/java/com/google/dexmaker/stock/ProxyBuilderTest.java b/src/test/java/com/google/dexmaker/stock/ProxyBuilderTest.java
index e6912c4..763d740 100644
--- a/src/test/java/com/google/dexmaker/stock/ProxyBuilderTest.java
+++ b/src/test/java/com/google/dexmaker/stock/ProxyBuilderTest.java
@@ -819,6 +819,20 @@ public class ProxyBuilderTest extends TestCase {
         assertEquals("no proxy", proxyFor(FinalToString.class).build().toString());
     }
 
+    public static class FinalInterfaceImpl implements FooReturnsString {
+        @Override public final String foo() {
+          return "no proxy";
+        }
+    }
+
+    public static class ExtenstionOfFinalInterfaceImpl extends FinalInterfaceImpl
+            implements FooReturnsString {
+    }
+
+    public void testFinalInterfaceImpl() throws Throwable {
+        assertEquals("no proxy", proxyFor(ExtenstionOfFinalInterfaceImpl.class).build().foo());
+    }
+
     /** Simple helper to add the most common args for this test to the proxy builder. */
     private <T> ProxyBuilder<T> proxyFor(Class<T> clazz) throws Exception {
         return ProxyBuilder.forClass(clazz)