From c7aaaa00fccc9a0f8cd053eb5b88885a11ef0ab8 Mon Sep 17 00:00:00 2001
From: Oliver Gierke <ogierke@pivotal.io>
Date: Mon, 15 Jan 2018 14:33:39 +0100
Subject: [PATCH] DATAREST-1177 - DefaultExposureAwareCrudMethods now caches
 results.

---
 .../CrudMethodsSupportedHttpMethods.java      | 33 +++++++++++++------
 1 file changed, 23 insertions(+), 10 deletions(-)

diff --git a/spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/CrudMethodsSupportedHttpMethods.java b/spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/CrudMethodsSupportedHttpMethods.java
index 45ff1196a..d66e9dbeb 100644
--- a/spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/CrudMethodsSupportedHttpMethods.java
+++ b/spring-data-rest-core/src/main/java/org/springframework/data/rest/core/mapping/CrudMethodsSupportedHttpMethods.java
@@ -18,9 +18,6 @@ package org.springframework.data.rest.core.mapping;
 import static org.springframework.data.rest.core.mapping.ResourceType.*;
 import static org.springframework.http.HttpMethod.*;
 
-import lombok.NonNull;
-import lombok.RequiredArgsConstructor;
-
 import java.lang.reflect.Method;
 import java.util.Collections;
 import java.util.HashSet;
@@ -31,6 +28,7 @@ import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.data.repository.core.CrudMethods;
 import org.springframework.data.rest.core.annotation.RestResource;
+import org.springframework.data.util.Lazy;
 import org.springframework.http.HttpMethod;
 import org.springframework.util.Assert;
 
@@ -141,19 +139,34 @@ public class CrudMethodsSupportedHttpMethods implements SupportedHttpMethods {
 	/**
 	 * @author Oliver Gierke
 	 */
-	@RequiredArgsConstructor
 	private static class DefaultExposureAwareCrudMethods implements ExposureAwareCrudMethods {
 
-		private final @NonNull CrudMethods crudMethods;
+		private final Lazy<Boolean> exposesSave;
+		private final Lazy<Boolean> exposesDelete;
+		private final Lazy<Boolean> exposesFindOne;
+		private final Lazy<Boolean> exposesFindAll;
+
 		private final boolean exportedDefault;
 
-		/* 
+		DefaultExposureAwareCrudMethods(CrudMethods crudMethods, boolean exportedDefault) {
+
+			Assert.notNull(crudMethods, "CrudMethods must not be null!");
+
+			this.exposesSave = Lazy.of(() -> exposes(crudMethods.getSaveMethod()));
+			this.exposesDelete = Lazy.of(() -> exposes(crudMethods.getDeleteMethod()) && crudMethods.hasFindOneMethod());
+			this.exposesFindOne = Lazy.of(() -> exposes(crudMethods.getFindOneMethod()));
+			this.exposesFindAll = Lazy.of(() -> exposes(crudMethods.getFindAllMethod()));
+
+			this.exportedDefault = exportedDefault;
+		}
+
+		/*
 		 * (non-Javadoc)
 		 * @see org.springframework.data.rest.core.mapping.ExposureAwareCrudMethods#exposesSave()
 		 */
 		@Override
 		public boolean exposesSave() {
-			return exposes(crudMethods.getSaveMethod());
+			return exposesSave.get();
 		}
 
 		/* 
@@ -162,7 +175,7 @@ public class CrudMethodsSupportedHttpMethods implements SupportedHttpMethods {
 		 */
 		@Override
 		public boolean exposesDelete() {
-			return exposes(crudMethods.getDeleteMethod()) && crudMethods.hasFindOneMethod();
+			return exposesDelete.get();
 		}
 
 		/* 
@@ -171,7 +184,7 @@ public class CrudMethodsSupportedHttpMethods implements SupportedHttpMethods {
 		 */
 		@Override
 		public boolean exposesFindOne() {
-			return exposes(crudMethods.getFindOneMethod());
+			return exposesFindOne.get();
 		}
 
 		/* 
@@ -180,7 +193,7 @@ public class CrudMethodsSupportedHttpMethods implements SupportedHttpMethods {
 		 */
 		@Override
 		public boolean exposesFindAll() {
-			return exposes(crudMethods.getFindAllMethod());
+			return exposesFindAll.get();
 		}
 
 		private boolean exposes(Optional<Method> method) {