Ensure that custom static resource locations end with /

Closes gh-9360

Author: wilkinsona

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/ResourceProperties.java

@@ -86,7 +86,16 @@ public String[] getStaticLocations() {
 	}
 
 	public void setStaticLocations(String[] staticLocations) {
-		this.staticLocations = staticLocations;
+		this.staticLocations = appendSlashIfNecessary(staticLocations);
+	}
+
+	private String[] appendSlashIfNecessary(String[] staticLocations) {
+		String[] normalized = new String[staticLocations.length];
+		for (int i = 0; i < staticLocations.length; i++) {
+			String location = staticLocations[i];
+			normalized[i] = location.endsWith("/") ? location : location + "/";
+		}
+		return normalized;
 	}
 
 	public Resource getWelcomePage() {

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/ResourcePropertiesTests.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.
@@ -18,7 +18,10 @@
 
 import org.junit.Test;
 
+import org.springframework.boot.testutil.Matched;
+
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.hamcrest.CoreMatchers.endsWith;
 
 /**
  * Tests for {@link ResourceProperties}.
@@ -52,4 +55,17 @@ public void resourceChainDisabled() {
 		assertThat(this.properties.getChain().getEnabled()).isFalse();
 	}
 
+	@Test
+	public void defaultStaticLocationsAllEndWithTrailingSlash() {
+		assertThat(this.properties.getStaticLocations()).are(Matched.by(endsWith("/")));
+	}
+
+	@Test
+	public void customStaticLocationsAreNormalizedToEndWithTrailingSlash() {
+		this.properties.setStaticLocations(new String[] { "/foo", "/bar", "/baz/" });
+		assertThat(this.properties.getStaticLocations()).containsExactly("/foo/", "/bar/",
+				"/baz/");
+
+	}
+
 }