Add @AutoConfigureBefore and simple implementation

[#54597932] [bs-273] Circular view reference for /error

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationSorter.java

@@ -20,6 +20,7 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
@@ -52,6 +53,7 @@ class AutoConfigurationSorter {
 
 	public List<String> getInPriorityOrder(Collection<String> classNames)
 			throws IOException {
+
 		List<AutoConfigurationClass> autoConfigurationClasses = new ArrayList<AutoConfigurationClass>();
 		for (String className : classNames) {
 			autoConfigurationClasses.add(new AutoConfigurationClass(className));
@@ -65,30 +67,52 @@ class AutoConfigurationSorter {
 
 		List<String> orderedClassNames = new ArrayList<String>();
 		for (AutoConfigurationClass autoConfigurationClass : autoConfigurationClasses) {
-			orderedClassNames.add(autoConfigurationClass.toString());
+			orderedClassNames.add(autoConfigurationClass.getClassName());
 		}
 		return orderedClassNames;
+
 	}
 
 	private List<AutoConfigurationClass> sortByAfterAnnotation(
 			Collection<AutoConfigurationClass> autoConfigurationClasses)
 			throws IOException {
-		List<AutoConfigurationClass> tosort = new ArrayList<AutoConfigurationClass>(
-				autoConfigurationClasses);
+
+		// Create a look up table of actual autoconfigs
+		Map<AutoConfigurationClass, AutoConfigurationClass> tosort = new LinkedHashMap<AutoConfigurationClass, AutoConfigurationClass>();
+		for (AutoConfigurationClass current : autoConfigurationClasses) {
+			tosort.put(current, current);
+		}
+		addAftersFromBefores(tosort);
+
 		Set<AutoConfigurationClass> sorted = new LinkedHashSet<AutoConfigurationClass>();
 		Set<AutoConfigurationClass> processing = new LinkedHashSet<AutoConfigurationClass>();
 		while (!tosort.isEmpty()) {
 			doSortByAfterAnnotation(tosort, sorted, processing, null);
 		}
+
 		return new ArrayList<AutoConfigurationClass>(sorted);
+
 	}
 
-	private void doSortByAfterAnnotation(List<AutoConfigurationClass> tosort,
+	private void addAftersFromBefores(
+			Map<AutoConfigurationClass, AutoConfigurationClass> map) throws IOException {
+		// Pick up any befores and add them to the corresponding after
+		for (AutoConfigurationClass current : map.keySet()) {
+			for (AutoConfigurationClass before : current.getBefore()) {
+				if (map.containsKey(before)) {
+					map.get(before).getAfter().add(current);
+				}
+			}
+		}
+	}
+
+	private void doSortByAfterAnnotation(
+			Map<AutoConfigurationClass, AutoConfigurationClass> tosort,
 			Set<AutoConfigurationClass> sorted, Set<AutoConfigurationClass> processing,
 			AutoConfigurationClass current) throws IOException {
 
 		if (current == null) {
-			current = tosort.remove(0);
+			current = tosort.remove(tosort.keySet().iterator().next());
 		}
 
 		processing.add(current);
@@ -97,8 +121,8 @@ class AutoConfigurationSorter {
 			Assert.state(!processing.contains(after),
 					"Cycle @AutoConfigureAfter detected between " + current + " and "
 							+ after);
-			if (!sorted.contains(after) && tosort.contains(after)) {
-				doSortByAfterAnnotation(tosort, sorted, processing, after);
+			if (!sorted.contains(after) && tosort.containsKey(after)) {
+				doSortByAfterAnnotation(tosort, sorted, processing, tosort.get(after));
 			}
 		}
 
@@ -110,12 +134,16 @@ class AutoConfigurationSorter {
 
 		private final String className;
 
-		private final int order;
+		private int order;
 
 		private List<AutoConfigurationClass> after;
 
+		private List<AutoConfigurationClass> before;
+
 		private Map<String, Object> afterAnnotation;
 
+		private Map<String, Object> beforeAnnotation;
+
 		public AutoConfigurationClass(String className) throws IOException {
 
 			this.className = className;
@@ -127,12 +155,15 @@ class AutoConfigurationSorter {
 			// Read @Order annotation
 			Map<String, Object> orderedAnnotation = metadata
 					.getAnnotationAttributes(Order.class.getName());
-			this.order = (orderedAnnotation == null ? Ordered.LOWEST_PRECEDENCE
-					: (Integer) orderedAnnotation.get("value"));
+			this.order = (orderedAnnotation == null ? 0 : (Integer) orderedAnnotation
+					.get("value"));
 
 			// Read @AutoConfigureAfter annotation
 			this.afterAnnotation = metadata.getAnnotationAttributes(
 					AutoConfigureAfter.class.getName(), true);
+			// Read @AutoConfigureBefore annotation
+			this.beforeAnnotation = metadata.getAnnotationAttributes(
+					AutoConfigureBefore.class.getName(), true);
 		}
 
 		@Override
@@ -140,10 +171,14 @@ class AutoConfigurationSorter {
 			return this.order;
 		}
 
+		public String getClassName() {
+			return this.className;
+		}
+
 		public List<AutoConfigurationClass> getAfter() throws IOException {
 			if (this.after == null) {
 				if (this.afterAnnotation == null) {
-					this.after = Collections.emptyList();
+					this.after = new ArrayList<AutoConfigurationClass>();
 				}
 				else {
 					this.after = new ArrayList<AutoConfigurationClass>();
@@ -155,6 +190,22 @@ class AutoConfigurationSorter {
 			return this.after;
 		}
 
+		public List<AutoConfigurationClass> getBefore() throws IOException {
+			if (this.before == null) {
+				if (this.beforeAnnotation == null) {
+					this.before = Collections.emptyList();
+				}
+				else {
+					this.before = new ArrayList<AutoConfigurationClass>();
+					for (String beforeClass : (String[]) this.beforeAnnotation
+							.get("value")) {
+						this.before.add(new AutoConfigurationClass(beforeClass));
+					}
+				}
+			}
+			return this.before;
+		}
+
 		@Override
 		public String toString() {
 			return this.className;
@@ -169,6 +220,7 @@ class AutoConfigurationSorter {
 		public boolean equals(Object obj) {
 			return this.className.equals(((AutoConfigurationClass) obj).className);
 		}
+
 	}
 
 }

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigureBefore.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2012-2013 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.autoconfigure;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Hint for that an {@link EnableAutoConfiguration auto-configuration} should be applied
+ * after the specified auto-configuration classes.
+ * 
+ * @author Phillip Webb
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ ElementType.TYPE })
+public @interface AutoConfigureBefore {
+	Class<?>[] value();
+}

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/AutoConfigurationSorterTests.java

@@ -16,20 +16,21 @@
 
 package org.springframework.boot.autoconfigure;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
+import org.hamcrest.Description;
+import org.hamcrest.Matcher;
+import org.hamcrest.core.IsEqual;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
-import org.springframework.boot.autoconfigure.AutoConfigurationSorter;
-import org.springframework.boot.autoconfigure.AutoConfigureAfter;
 import org.springframework.core.Ordered;
 import org.springframework.core.annotation.Order;
 import org.springframework.core.io.DefaultResourceLoader;
 
-import static org.hamcrest.Matchers.equalTo;
 import static org.junit.Assert.assertThat;
 
 /**
@@ -37,7 +38,7 @@ import static org.junit.Assert.assertThat;
  * 
  * @author Phillip Webb
  */
-public class AutoConfigurationSorterTest {
+public class AutoConfigurationSorterTests {
 
 	private static final String LOWEST = OrderLowest.class.getName();
 	private static final String HIGHEST = OrderHighest.class.getName();
@@ -45,6 +46,11 @@ public class AutoConfigurationSorterTest {
 	private static final String B = AutoConfigureB.class.getName();
 	private static final String C = AutoConfigureC.class.getName();
 	private static final String D = AutoConfigureD.class.getName();
+	private static final String E = AutoConfigureE.class.getName();
+	private static final String W = AutoConfigureW.class.getName();
+	private static final String X = AutoConfigureX.class.getName();
+	private static final String Y = AutoConfigureY.class.getName();
+	private static final String Z = AutoConfigureZ.class.getName();
 
 	@Rule
 	public ExpectedException thrown = ExpectedException.none();
@@ -60,19 +66,38 @@ public class AutoConfigurationSorterTest {
 	public void byOrderAnnotation() throws Exception {
 		List<String> actual = this.sorter.getInPriorityOrder(Arrays.asList(LOWEST,
 				HIGHEST));
-		assertThat(actual, equalTo(Arrays.asList(HIGHEST, LOWEST)));
+		assertThat(actual, nameMatcher(HIGHEST, LOWEST));
 	}
 
 	@Test
 	public void byAutoConfigureAfter() throws Exception {
 		List<String> actual = this.sorter.getInPriorityOrder(Arrays.asList(A, B, C));
-		assertThat(actual, equalTo(Arrays.asList(C, B, A)));
+		assertThat(actual, nameMatcher(C, B, A));
+	}
+
+	@Test
+	public void byAutoConfigureBefore() throws Exception {
+		List<String> actual = this.sorter.getInPriorityOrder(Arrays.asList(X, Y, Z));
+		assertThat(actual, nameMatcher(Z, Y, X));
+	}
+
+	@Test
+	public void byAutoConfigureAfterDoubles() throws Exception {
+		List<String> actual = this.sorter.getInPriorityOrder(Arrays.asList(A, B, C, E));
+		assertThat(actual, nameMatcher(C, E, B, A));
+	}
+
+	@Test
+	public void byAutoConfigureMixedBeforeAndAfter() throws Exception {
+		List<String> actual = this.sorter
+				.getInPriorityOrder(Arrays.asList(A, B, C, W, X));
+		assertThat(actual, nameMatcher(C, W, B, A, X));
 	}
 
 	@Test
 	public void byAutoConfigureAfterWithMissing() throws Exception {
 		List<String> actual = this.sorter.getInPriorityOrder(Arrays.asList(A, B));
-		assertThat(actual, equalTo(Arrays.asList(B, A)));
+		assertThat(actual, nameMatcher(B, A));
 	}
 
 	@Test
@@ -82,6 +107,39 @@ public class AutoConfigurationSorterTest {
 		this.sorter.getInPriorityOrder(Arrays.asList(A, B, C, D));
 	}
 
+	private Matcher<? super List<String>> nameMatcher(String... names) {
+
+		final List<String> list = Arrays.asList(names);
+
+		return new IsEqual<List<String>>(list) {
+
+			@Override
+			public void describeMismatch(Object item, Description description) {
+				@SuppressWarnings("unchecked")
+				List<String> items = (List<String>) item;
+				description.appendText("was ").appendValue(prettify(items));
+			}
+
+			@Override
+			public void describeTo(Description description) {
+				description.appendValue(prettify(list));
+			}
+
+			private String prettify(List<String> items) {
+				List<String> pretty = new ArrayList<String>();
+				for (String item : items) {
+					if (item.contains("$AutoConfigure")) {
+						item = item.substring(item.indexOf("$AutoConfigure")
+								+ "$AutoConfigure".length());
+					}
+					pretty.add(item);
+				}
+				return pretty.toString();
+			}
+		};
+
+	}
+
 	@Order(Ordered.LOWEST_PRECEDENCE)
 	public static class OrderLowest {
 	}
@@ -94,7 +152,8 @@ public class AutoConfigurationSorterTest {
 	public static class AutoConfigureA {
 	}
 
-	@AutoConfigureAfter({ AutoConfigureC.class, AutoConfigureD.class })
+	@AutoConfigureAfter({ AutoConfigureC.class, AutoConfigureD.class,
+			AutoConfigureE.class })
 	public static class AutoConfigureB {
 	}
 
@@ -104,4 +163,23 @@ public class AutoConfigurationSorterTest {
 	@AutoConfigureAfter(AutoConfigureA.class)
 	public static class AutoConfigureD {
 	}
+
+	public static class AutoConfigureE {
+	}
+
+	@AutoConfigureBefore(AutoConfigureB.class)
+	public static class AutoConfigureW {
+	}
+
+	public static class AutoConfigureX {
+	}
+
+	@AutoConfigureBefore(AutoConfigureX.class)
+	public static class AutoConfigureY {
+	}
+
+	@AutoConfigureBefore(AutoConfigureY.class)
+	public static class AutoConfigureZ {
+	}
+
 }