Polish contribution

See gh-24293

spring-aop/src/main/java/org/springframework/aop/interceptor/ExposeInvocationInterceptor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -71,11 +71,11 @@ public final class ExposeInvocationInterceptor implements MethodInterceptor, Pri
 		MethodInvocation mi = invocation.get();
 		if (mi == null) {
 			throw new IllegalStateException(
-					"No MethodInvocation found: Check that an AOP invocation is in progress, and that the " +
+					"No MethodInvocation found: Check that an AOP invocation is in progress and that the " +
 					"ExposeInvocationInterceptor is upfront in the interceptor chain. Specifically, note that " +
 					"advices with order HIGHEST_PRECEDENCE will execute before ExposeInvocationInterceptor! " +
-					"Check that ExposeInvocationInterceptor and ExposeInvocationInterceptor.currentInvocation() " +
-					"invoke in one Thread");
+					"In addition, ExposeInvocationInterceptor and ExposeInvocationInterceptor.currentInvocation() " +
+					"must be invoked from the same thread.");
 		}
 		return mi;
 	}