Fix typos

Closes gh-13762

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jersey/JerseyAutoConfigurationObjectMapperProviderTests.java

 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -49,7 +49,7 @@ import org.springframework.test.context.junit4.SpringRunner;
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
- * Tests for {@link JerseyAutoConfiguration} with a ObjectMapper.
+ * Tests for {@link JerseyAutoConfiguration} with an ObjectMapper.
  *
  * @author Eddú Meléndez
  * @author Andy Wilkinson

spring-boot-project/spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -821,7 +821,7 @@ properties in the `server` namespace anymore.
 
 
 [[howto-add-a-servlet-filter-or-listener]]
-=== Add a Servlet, Filter, or Listener to a Application
+=== Add a Servlet, Filter, or Listener to an Application
 In a servlet stack application, i.e. with the `spring-boot-starter-web`, there are two
 ways to add `Servlet`, `Filter`, `ServletContextListener`, and the other listeners
 supported by the Servlet API to your application:

spring-boot-project/spring-boot-tools/spring-boot-configuration-processor/src/json-shade/java/org/springframework/boot/configurationprocessor/json/JSONArray.java

@@ -405,7 +405,7 @@ public class JSONArray {
 	 * @param index the index to get the value from
 	 * @return the {@code value}
 	 * @throws JSONException if the value at {@code index} doesn't exist or cannot be
-	 * coerced to a int.
+	 * coerced to an int.
 	 */
 	public int getInt(int index) throws JSONException {
 		Object object = get(index);