/* * Copyright 2002-2016 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.expression.spel.support; import java.lang.reflect.Method; import java.util.ArrayList; import java.util.List; import org.junit.Ignore; import org.junit.Test; import org.springframework.core.MethodParameter; import org.springframework.core.convert.TypeDescriptor; import org.springframework.expression.MethodExecutor; public class Spr7538Tests { @Ignore @Test public void repro() throws Exception { AlwaysTrueReleaseStrategy target = new AlwaysTrueReleaseStrategy(); BeanFactoryTypeConverter converter = new BeanFactoryTypeConverter(); StandardEvaluationContext context = new StandardEvaluationContext(); context.setTypeConverter(converter); List<Foo> arguments = new ArrayList<>(); // !!!! With the below line commented you'll get NPE. Uncomment and everything is OK! //arguments.add(new Foo()); List<TypeDescriptor> paramDescriptors = new ArrayList<>(); Method method = AlwaysTrueReleaseStrategy.class.getMethod("checkCompleteness", List.class); paramDescriptors.add(new TypeDescriptor(new MethodParameter(method, 0))); List<TypeDescriptor> argumentTypes = new ArrayList<>(); argumentTypes.add(TypeDescriptor.forObject(arguments)); ReflectiveMethodResolver resolver = new ReflectiveMethodResolver(); MethodExecutor executor = resolver.resolve(context, target, "checkCompleteness", argumentTypes); Object result = executor.execute(context, target, arguments); System.out.println("Result: " + result); } public static class AlwaysTrueReleaseStrategy { public boolean checkCompleteness(List<Foo> messages) { return true; } } public static class Foo{} }