[LANG-1789] NullPointerException when generating NoSuchMethodException

in MethodUtils

Author: garydgregory

src/changes/changes.xml

@@ -53,6 +53,7 @@ The <action> type attribute can be add,update,fix,remove.
     <action                   type="fix" dev="ggregory" due-to="jack5505, Gary Gregory">`LocaleUtils.toLocale(String)` for a 2 letter country code now returns a value instead of throwing an `IllegalArgumentException`.</action>
     <action                   type="fix" dev="ggregory" due-to="mayuming, Gary Gregory">Fix typo in StringUtils.trunctate() IllegalArgumentException message and test assertion messages.</action>
     <action                   type="fix" dev="ggregory" due-to="mayuming, Gary Gregory">Fix test fixture in ReflectionDiffBuilderTest.testTransientFieldDifference() #1464.</action>
+    <action issue="LANG-1789" type="fix" dev="ggregory" due-to="Hylke van der Schaaf, Gary Gregory">NullPointerException when generating NoSuchMethodException in MethodUtils.</action>
     <!-- ADD -->
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add SystemProperties.getPath(String, Supplier&lt;Path&gt;).</action>
     <action                   type="add" dev="ggregory" due-to="Gary Gregory">Add JavaVersion.JAVA_25.</action>

src/main/java/org/apache/commons/lang3/reflect/MethodUtils.java

@@ -1023,7 +1023,7 @@ private static Method requireNonNull(final Method method, final Class<?> cls, fi
             throws NoSuchMethodException {
         if (method == null) {
             throw new NoSuchMethodException(String.format("No method: %s.%s(%s)", cls.getName(), methodName,
-                    Stream.of(parameterTypes).map(Class::getName).collect(LangCollectors.joining(", "))));
+                    Stream.of(parameterTypes).map(c -> c != null ? c.getName() : null).collect(LangCollectors.joining(", "))));
         }
         return method;
     }

src/test/java/org/apache/commons/lang3/reflect/MethodUtilsTest.java

@@ -1110,6 +1110,9 @@ void testInvokeMethod() throws Exception {
     void testInvokeMethod_VarArgsWithNullValues() throws Exception {
         assertEquals("String...", MethodUtils.invokeMethod(testBean, "varOverload", "a", null, "c"));
         assertEquals("String...", MethodUtils.invokeMethod(testBean, "varOverload", "a", "b", null));
+        assertEquals("String...", MethodUtils.invokeMethod(testBean, "varOverload", new String[] { "a" }, new Class<?>[] { String.class }));
+        assertThrows(NoSuchMethodException.class,
+                () -> assertEquals("String...", MethodUtils.invokeMethod(testBean, "doesn't exist", new String[] { "a" }, new Class<?>[] { null })));
     }
 
     @Test