diff --git a/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManager.java b/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManager.java
index e3fb358b01..f0f9edc815 100644
--- a/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManager.java
+++ b/spring-boot-test-autoconfigure/src/main/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManager.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -224,7 +224,7 @@ public class TestEntityManager {
 	@SuppressWarnings("unchecked")
 	public <T> T getId(Object entity, Class<T> idType) {
 		Object id = getId(entity);
-		Assert.isInstanceOf(idType, id, "ID mismatch");
+		Assert.isInstanceOf(idType, id, "ID mismatch:");
 		return (T) id;
 	}
 
diff --git a/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManagerTests.java b/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManagerTests.java
index d34168266f..23a48c8a2b 100644
--- a/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManagerTests.java
+++ b/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/orm/jpa/TestEntityManagerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -191,7 +191,8 @@ public class TestEntityManagerTests {
 	public void getIdForTypeWhenTypeIsWrongShouldThrowException() throws Exception {
 		TestEntity entity = new TestEntity();
 		given(this.persistenceUnitUtil.getIdentifier(entity)).willReturn(123);
-		this.thrown.expectMessage("ID mismatch: java.lang.Integer");
+		this.thrown.expectMessage("ID mismatch: Object of class [java.lang.Integer] "
+				+ "must be an instance of class java.lang.Long");
 		this.testEntityManager.getId(entity, Long.class);
 	}