From ac68cc35c2cf776d66c41e8544663f0db1f17166 Mon Sep 17 00:00:00 2001
From: Eko Kurniawan Khannedy <eko.k.khannedy@gdn-commerce.com>
Date: Sat, 3 Jun 2017 12:09:28 +0700
Subject: [PATCH] Ordered WebMvcConfigurer interceptor registrations

Issue: SPR-15620
---
 .../annotation/InterceptorRegistration.java   | 17 ++++++++++++-
 .../annotation/InterceptorRegistry.java       | 13 +++++-----
 .../annotation/InterceptorRegistryTests.java  | 25 +++++++++++++++++++
 3 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistration.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistration.java
index c91a6f80eef..5bd6ff8f9be 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistration.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistration.java
@@ -20,6 +20,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
+import org.springframework.core.Ordered;
 import org.springframework.util.Assert;
 import org.springframework.util.PathMatcher;
 import org.springframework.util.StringUtils;
@@ -33,7 +34,7 @@ import org.springframework.web.servlet.handler.MappedInterceptor;
  * @author Keith Donald
  * @since 3.1
  */
-public class InterceptorRegistration {
+public class InterceptorRegistration implements Ordered {
 
 	private final HandlerInterceptor interceptor;
 
@@ -43,6 +44,7 @@ public class InterceptorRegistration {
 
 	private PathMatcher pathMatcher;
 
+	private int order = 0;
 
 	/**
 	 * Creates an {@link InterceptorRegistration} instance.
@@ -99,4 +101,17 @@ public class InterceptorRegistration {
 		return mappedInterceptor;
 	}
 
+	/**
+	 * An order position to be used, default is 0.
+	 */
+	public InterceptorRegistration order(int order){
+		this.order = order;
+		return this;
+	}
+
+	@Override
+	public int getOrder() {
+		return order;
+	}
+
 }
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistry.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistry.java
index 6104acde637..0e4f4357ebb 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistry.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/config/annotation/InterceptorRegistry.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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 +18,9 @@ package org.springframework.web.servlet.config.annotation;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.stream.Collectors;
 
+import org.springframework.core.OrderComparator;
 import org.springframework.web.context.request.WebRequestInterceptor;
 import org.springframework.web.servlet.HandlerInterceptor;
 import org.springframework.web.servlet.handler.WebRequestHandlerInterceptorAdapter;
@@ -64,11 +66,10 @@ public class InterceptorRegistry {
 	 * Return all registered interceptors.
 	 */
 	protected List<Object> getInterceptors() {
-		List<Object> interceptors = new ArrayList<>(this.registrations.size());
-		for (InterceptorRegistration registration : this.registrations) {
-			interceptors.add(registration.getInterceptor());
-		}
-		return interceptors ;
+		return this.registrations.stream()
+				.sorted(OrderComparator.INSTANCE)
+				.map(InterceptorRegistration::getInterceptor)
+				.collect(Collectors.toList());
 	}
 
 }
diff --git a/spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/InterceptorRegistryTests.java b/spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/InterceptorRegistryTests.java
index c6bc02f71d1..1c586d0aafd 100644
--- a/spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/InterceptorRegistryTests.java
+++ b/spring-webmvc/src/test/java/org/springframework/web/servlet/config/annotation/InterceptorRegistryTests.java
@@ -25,6 +25,7 @@ import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mockito;
 
+import org.springframework.core.Ordered;
 import org.springframework.lang.Nullable;
 import org.springframework.mock.web.test.MockHttpServletRequest;
 import org.springframework.mock.web.test.MockHttpServletResponse;
@@ -46,6 +47,7 @@ import static org.junit.Assert.*;
  * {@link WebRequestInterceptor}s.
  *
  * @author Rossen Stoyanchev
+ * @author Eko Kurniawan Khannedy
  */
 public class InterceptorRegistryTests {
 
@@ -194,4 +196,27 @@ public class InterceptorRegistryTests {
 		}
 	}
 
+	@Test
+	public void orderedInterceptors() throws Exception {
+		registry.addInterceptor(interceptor1).order(Ordered.LOWEST_PRECEDENCE);
+		registry.addInterceptor(interceptor2).order(Ordered.HIGHEST_PRECEDENCE);
+
+		List<Object> interceptors = registry.getInterceptors();
+		assertEquals(2, interceptors.size());
+
+		assertSame(interceptor2, interceptors.get(0));
+		assertSame(interceptor1, interceptors.get(1));
+	}
+
+	@Test
+	public void nonOrderedInterceptors() throws Exception {
+		registry.addInterceptor(interceptor1).order(0);
+		registry.addInterceptor(interceptor2).order(0);
+
+		List<Object> interceptors = registry.getInterceptors();
+		assertEquals(2, interceptors.size());
+
+		assertSame(interceptor1, interceptors.get(0));
+		assertSame(interceptor2, interceptors.get(1));
+	}
 }