src/share/classes/java/lang/reflect/Method.java

@@ -502,10 +502,26 @@
     @Override
     public boolean isSynthetic() {
         return super.isSynthetic();
     }
 
+    /**
+     * Returns {@code true} if this method is a default
+     * method; returns {@code false} otherwise.
+     *
+     * A default method is a non-abstract method, that is, a method
+     * with a body, declared in an interface type.
+     *
+     * @return true if and only if this method is a default
+     * method as defined by the Java Language Specification.
+     * @since 1.8
+     */
+    public boolean isDefault() {
+        return (getModifiers() & Modifier.ABSTRACT) == 0 &&
+            getDeclaringClass().isInterface();
+    }
+
     // NOTE that there is no synchronization used here. It is correct
     // (though not efficient) to generate more than one MethodAccessor
     // for a given Method. However, avoiding synchronization will
     // probably make the implementation more scalable.
     private MethodAccessor acquireMethodAccessor() {