Merge branch '2.7.x' into 3.0.x

Closes gh-37223

buildSrc/src/main/java/org/springframework/boot/build/bom/BomExtension.java

@@ -113,8 +113,8 @@ public class BomExtension {
 		LibraryHandler libraryHandler = objects.newInstance(LibraryHandler.class, (version != null) ? version : "");
 		action.execute(libraryHandler);
 		LibraryVersion libraryVersion = new LibraryVersion(DependencyVersion.parse(libraryHandler.version));
-		addLibrary(new Library(name, libraryVersion, libraryHandler.groups, libraryHandler.prohibitedVersions,
-				libraryHandler.considerSnapshots));
+		addLibrary(new Library(name, libraryHandler.calendarName, libraryVersion, libraryHandler.groups,
+				libraryHandler.prohibitedVersions, libraryHandler.considerSnapshots));
 	}
 
 	public void effectiveBomArtifact() {
@@ -218,6 +218,8 @@ public class BomExtension {
 
 		private String version;
 
+		private String calendarName;
+
 		@Inject
 		public LibraryHandler(String version) {
 			this.version = version;
@@ -231,6 +233,10 @@ public class BomExtension {
 			this.considerSnapshots = true;
 		}
 
+		public void setCalendarName(String calendarName) {
+			this.calendarName = calendarName;
+		}
+
 		public void group(String id, Action<GroupHandler> action) {
 			GroupHandler groupHandler = new GroupHandler(id);
 			action.execute(groupHandler);

buildSrc/src/main/java/org/springframework/boot/build/bom/Library.java

@@ -34,6 +34,8 @@ public class Library {
 
 	private final String name;
 
+	private final String calendarName;
+
 	private final LibraryVersion version;
 
 	private final List<Group> groups;
@@ -48,14 +50,17 @@ public class Library {
 	 * Create a new {@code Library} with the given {@code name}, {@code version}, and
 	 * {@code groups}.
 	 * @param name name of the library
+	 * @param calendarName name of the library as it appears in the Spring Calendar. May
+	 * be {@code null} in which case the {@code name} is used.
 	 * @param version version of the library
 	 * @param groups groups in the library
 	 * @param prohibitedVersions version of the library that are prohibited
 	 * @param considerSnapshots whether to consider snapshots
 	 */
-	public Library(String name, LibraryVersion version, List<Group> groups, List<ProhibitedVersion> prohibitedVersions,
-			boolean considerSnapshots) {
+	public Library(String name, String calendarName, LibraryVersion version, List<Group> groups,
+			List<ProhibitedVersion> prohibitedVersions, boolean considerSnapshots) {
 		this.name = name;
+		this.calendarName = (calendarName != null) ? calendarName : name;
 		this.version = version;
 		this.groups = groups;
 		this.versionProperty = "Spring Boot".equals(name) ? null
@@ -68,6 +73,10 @@ public class Library {
 		return this.name;
 	}
 
+	public String getCalendarName() {
+		return this.calendarName;
+	}
+
 	public LibraryVersion getVersion() {
 		return this.version;
 	}

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/MoveToSnapshots.java

@@ -17,13 +17,23 @@
 package org.springframework.boot.build.bom.bomr;
 
 import java.net.URI;
+import java.time.OffsetDateTime;
+import java.util.List;
+import java.util.Map;
+import java.util.function.BiPredicate;
 
 import javax.inject.Inject;
 
 import org.gradle.api.Task;
+import org.gradle.api.tasks.TaskAction;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import org.springframework.boot.build.bom.BomExtension;
 import org.springframework.boot.build.bom.Library;
+import org.springframework.boot.build.bom.bomr.ReleaseSchedule.Release;
+import org.springframework.boot.build.bom.bomr.github.Milestone;
+import org.springframework.boot.build.bom.bomr.version.DependencyVersion;
 
 /**
  * A {@link Task} to move to snapshot dependencies.
@@ -32,6 +42,8 @@ import org.springframework.boot.build.bom.Library;
  */
 public abstract class MoveToSnapshots extends UpgradeDependencies {
 
+	private static final Logger log = LoggerFactory.getLogger(MoveToSnapshots.class);
+
 	private final URI REPOSITORY_URI = URI.create("https://repo.spring.io/snapshot/");
 
 	@Inject
@@ -40,6 +52,12 @@ public abstract class MoveToSnapshots extends UpgradeDependencies {
 		getRepositoryUris().add(this.REPOSITORY_URI);
 	}
 
+	@Override
+	@TaskAction
+	void upgradeDependencies() {
+		super.upgradeDependencies();
+	}
+
 	@Override
 	protected String issueTitle(Upgrade upgrade) {
 		String snapshotVersion = upgrade.getVersion().toString();
@@ -63,4 +81,28 @@ public abstract class MoveToSnapshots extends UpgradeDependencies {
 		return library.isConsiderSnapshots() && super.eligible(library);
 	}
 
+	@Override
+	protected List<BiPredicate<Library, DependencyVersion>> determineUpdatePredicates(Milestone milestone) {
+		ReleaseSchedule releaseSchedule = new ReleaseSchedule();
+		Map<String, List<Release>> releases = releaseSchedule.releasesBetween(OffsetDateTime.now(),
+				milestone.getDueOn());
+		List<BiPredicate<Library, DependencyVersion>> predicates = super.determineUpdatePredicates(milestone);
+		predicates.add((library, candidate) -> {
+			List<Release> releasesForLibrary = releases.get(library.getCalendarName());
+			if (releasesForLibrary != null) {
+				for (Release release : releasesForLibrary) {
+					if (candidate.isSnapshotFor(release.getVersion())) {
+						return true;
+					}
+				}
+			}
+			if (log.isInfoEnabled()) {
+				log.info("Ignoring " + candidate + ". No release of " + library.getName() + " scheduled before "
+						+ milestone.getDueOn());
+			}
+			return false;
+		});
+		return predicates;
+	}
+
 }

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/ReleaseSchedule.java

@@ -0,0 +1,108 @@
+/*
+ * Copyright 2023 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
+ *
+ *      https://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.build.bom.bomr;
+
+import java.time.LocalDate;
+import java.time.OffsetDateTime;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.springframework.boot.build.bom.bomr.version.DependencyVersion;
+import org.springframework.http.ResponseEntity;
+import org.springframework.util.LinkedCaseInsensitiveMap;
+import org.springframework.web.client.RestOperations;
+import org.springframework.web.client.RestTemplate;
+
+/**
+ * Release schedule for Spring projects, retrieved from
+ * <a href="https://calendar.spring.io">https://calendar.spring.io</a>.
+ *
+ * @author Andy Wilkinson
+ */
+class ReleaseSchedule {
+
+	private static final Pattern LIBRARY_AND_VERSION = Pattern.compile("([A-Za-z0-9 ]+) ([0-9A-Za-z.-]+)");
+
+	private final RestOperations rest;
+
+	ReleaseSchedule() {
+		this(new RestTemplate());
+	}
+
+	ReleaseSchedule(RestOperations rest) {
+		this.rest = rest;
+	}
+
+	@SuppressWarnings({ "unchecked", "rawtypes" })
+	Map<String, List<Release>> releasesBetween(OffsetDateTime start, OffsetDateTime end) {
+		ResponseEntity<List> response = this.rest
+			.getForEntity("https://calendar.spring.io/releases?start=" + start + "&end=" + end, List.class);
+		List<Map<String, String>> body = response.getBody();
+		Map<String, List<Release>> releasesByLibrary = new LinkedCaseInsensitiveMap<>();
+		body.stream()
+			.map(this::asRelease)
+			.filter(Objects::nonNull)
+			.forEach((release) -> releasesByLibrary.computeIfAbsent(release.getLibraryName(), (l) -> new ArrayList<>())
+				.add(release));
+		return releasesByLibrary;
+	}
+
+	private Release asRelease(Map<String, String> entry) {
+		LocalDate due = LocalDate.parse(entry.get("start"));
+		String title = entry.get("title");
+		Matcher matcher = LIBRARY_AND_VERSION.matcher(title);
+		if (!matcher.matches()) {
+			return null;
+		}
+		String library = matcher.group(1);
+		String version = matcher.group(2);
+		return new Release(library, DependencyVersion.parse(version), due);
+	}
+
+	static class Release {
+
+		private final String libraryName;
+
+		private final DependencyVersion version;
+
+		private final LocalDate dueOn;
+
+		Release(String libraryName, DependencyVersion version, LocalDate dueOn) {
+			this.libraryName = libraryName;
+			this.version = version;
+			this.dueOn = dueOn;
+		}
+
+		String getLibraryName() {
+			return this.libraryName;
+		}
+
+		DependencyVersion getVersion() {
+			return this.version;
+		}
+
+		LocalDate getDueOn() {
+			return this.dueOn;
+		}
+
+	}
+
+}

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/StandardLibraryUpdateResolver.java

@@ -24,17 +24,15 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.SortedSet;
+import java.util.function.BiPredicate;
 import java.util.stream.Collectors;
 
-import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import org.springframework.boot.build.bom.Library;
 import org.springframework.boot.build.bom.Library.Group;
 import org.springframework.boot.build.bom.Library.Module;
-import org.springframework.boot.build.bom.Library.ProhibitedVersion;
-import org.springframework.boot.build.bom.UpgradePolicy;
 import org.springframework.boot.build.bom.bomr.version.DependencyVersion;
 
 /**
@@ -48,15 +46,21 @@ class StandardLibraryUpdateResolver implements LibraryUpdateResolver {
 
 	private final VersionResolver versionResolver;
 
-	private final UpgradePolicy upgradePolicy;
+	private final BiPredicate<Library, DependencyVersion> predicate;
 
-	private final boolean movingToSnapshots;
-
-	StandardLibraryUpdateResolver(VersionResolver versionResolver, UpgradePolicy upgradePolicy,
-			boolean movingToSnapshots) {
+	StandardLibraryUpdateResolver(VersionResolver versionResolver,
+			List<BiPredicate<Library, DependencyVersion>> predicates) {
 		this.versionResolver = versionResolver;
-		this.upgradePolicy = upgradePolicy;
-		this.movingToSnapshots = movingToSnapshots;
+		BiPredicate<Library, DependencyVersion> predicate = null;
+		for (BiPredicate<Library, DependencyVersion> p : predicates) {
+			if (predicate == null) {
+				predicate = p;
+			}
+			else {
+				predicate = predicate.and(p);
+			}
+		}
+		this.predicate = predicate;
 	}
 
 	@Override
@@ -87,26 +91,24 @@ class StandardLibraryUpdateResolver implements LibraryUpdateResolver {
 
 	private List<VersionOption> determineResolvedVersionOptions(Library library) {
 		Map<String, SortedSet<DependencyVersion>> moduleVersions = new LinkedHashMap<>();
-		DependencyVersion libraryVersion = library.getVersion().getVersion();
 		for (Group group : library.getGroups()) {
 			for (Module module : group.getModules()) {
 				moduleVersions.put(group.getId() + ":" + module.getName(),
-						getLaterVersionsForModule(group.getId(), module.getName(), libraryVersion));
+						getLaterVersionsForModule(group.getId(), module.getName(), library));
 			}
 			for (String bom : group.getBoms()) {
-				moduleVersions.put(group.getId() + ":" + bom,
-						getLaterVersionsForModule(group.getId(), bom, libraryVersion));
+				moduleVersions.put(group.getId() + ":" + bom, getLaterVersionsForModule(group.getId(), bom, library));
 			}
 			for (String plugin : group.getPlugins()) {
 				moduleVersions.put(group.getId() + ":" + plugin,
-						getLaterVersionsForModule(group.getId(), plugin, libraryVersion));
+						getLaterVersionsForModule(group.getId(), plugin, library));
 			}
 		}
 		List<DependencyVersion> allVersions = moduleVersions.values()
 			.stream()
 			.flatMap(SortedSet::stream)
 			.distinct()
-			.filter((dependencyVersion) -> isPermitted(dependencyVersion, library.getProhibitedVersions()))
+			.filter((dependencyVersion) -> this.predicate.test(library, dependencyVersion))
 			.toList();
 		if (allVersions.isEmpty()) {
 			return Collections.emptyList();
@@ -117,32 +119,6 @@ class StandardLibraryUpdateResolver implements LibraryUpdateResolver {
 			.collect(Collectors.toList());
 	}
 
-	private boolean isPermitted(DependencyVersion dependencyVersion, List<ProhibitedVersion> prohibitedVersions) {
-		for (ProhibitedVersion prohibitedVersion : prohibitedVersions) {
-			String dependencyVersionToString = dependencyVersion.toString();
-			if (prohibitedVersion.getRange() != null && prohibitedVersion.getRange()
-				.containsVersion(new DefaultArtifactVersion(dependencyVersionToString))) {
-				return false;
-			}
-			for (String startsWith : prohibitedVersion.getStartsWith()) {
-				if (dependencyVersionToString.startsWith(startsWith)) {
-					return false;
-				}
-			}
-			for (String endsWith : prohibitedVersion.getEndsWith()) {
-				if (dependencyVersionToString.endsWith(endsWith)) {
-					return false;
-				}
-			}
-			for (String contains : prohibitedVersion.getContains()) {
-				if (dependencyVersionToString.contains(contains)) {
-					return false;
-				}
-			}
-		}
-		return true;
-	}
-
 	private List<String> getMissingModules(Map<String, SortedSet<DependencyVersion>> moduleVersions,
 			DependencyVersion version) {
 		List<String> missingModules = new ArrayList<>();
@@ -154,12 +130,8 @@ class StandardLibraryUpdateResolver implements LibraryUpdateResolver {
 		return missingModules;
 	}
 
-	private SortedSet<DependencyVersion> getLaterVersionsForModule(String groupId, String artifactId,
-			DependencyVersion currentVersion) {
-		SortedSet<DependencyVersion> versions = this.versionResolver.resolveVersions(groupId, artifactId);
-		versions.removeIf((candidate) -> !this.upgradePolicy.test(candidate, currentVersion));
-		versions.removeIf((candidate) -> !currentVersion.isUpgrade(candidate, this.movingToSnapshots));
-		return versions;
+	private SortedSet<DependencyVersion> getLaterVersionsForModule(String groupId, String artifactId, Library library) {
+		return this.versionResolver.resolveVersions(groupId, artifactId);
 	}
 
 }

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/UpgradeDependencies.java

@@ -27,11 +27,13 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.Properties;
 import java.util.Set;
+import java.util.function.BiPredicate;
 import java.util.function.Predicate;
 import java.util.regex.Pattern;
 
 import javax.inject.Inject;
 
+import org.apache.maven.artifact.versioning.DefaultArtifactVersion;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.InvalidUserDataException;
 import org.gradle.api.internal.tasks.userinput.UserInputHandler;
@@ -45,10 +47,12 @@ import org.gradle.api.tasks.options.Option;
 
 import org.springframework.boot.build.bom.BomExtension;
 import org.springframework.boot.build.bom.Library;
+import org.springframework.boot.build.bom.Library.ProhibitedVersion;
 import org.springframework.boot.build.bom.bomr.github.GitHub;
 import org.springframework.boot.build.bom.bomr.github.GitHubRepository;
 import org.springframework.boot.build.bom.bomr.github.Issue;
 import org.springframework.boot.build.bom.bomr.github.Milestone;
+import org.springframework.boot.build.bom.bomr.version.DependencyVersion;
 import org.springframework.util.StringUtils;
 
 /**
@@ -70,8 +74,8 @@ public abstract class UpgradeDependencies extends DefaultTask {
 
 	protected UpgradeDependencies(BomExtension bom, boolean movingToSnapshots) {
 		this.bom = bom;
-		this.movingToSnapshots = movingToSnapshots;
 		getThreads().convention(2);
+		this.movingToSnapshots = movingToSnapshots;
 	}
 
 	@Input
@@ -97,7 +101,7 @@ public abstract class UpgradeDependencies extends DefaultTask {
 				this.bom.getUpgrade().getGitHub().getRepository());
 		List<String> issueLabels = verifyLabels(repository);
 		Milestone milestone = determineMilestone(repository);
-		List<Upgrade> upgrades = resolveUpgrades();
+		List<Upgrade> upgrades = resolveUpgrades(milestone);
 		applyUpgrades(repository, issueLabels, milestone, upgrades);
 	}
 
@@ -213,15 +217,52 @@ public abstract class UpgradeDependencies extends DefaultTask {
 	}
 
 	@SuppressWarnings("deprecation")
-	private List<Upgrade> resolveUpgrades() {
+	private List<Upgrade> resolveUpgrades(Milestone milestone) {
 		List<Upgrade> upgrades = new InteractiveUpgradeResolver(getServices().get(UserInputHandler.class),
 				new MultithreadedLibraryUpdateResolver(getThreads().get(),
 						new StandardLibraryUpdateResolver(new MavenMetadataVersionResolver(getRepositoryUris().get()),
-								this.bom.getUpgrade().getPolicy(), this.movingToSnapshots)))
+								determineUpdatePredicates(milestone))))
 			.resolveUpgrades(matchingLibraries(), this.bom.getLibraries());
 		return upgrades;
 	}
 
+	protected List<BiPredicate<Library, DependencyVersion>> determineUpdatePredicates(Milestone milestone) {
+		BiPredicate<Library, DependencyVersion> compilesWithUpgradePolicy = (library,
+				candidate) -> this.bom.getUpgrade().getPolicy().test(candidate, library.getVersion().getVersion());
+		BiPredicate<Library, DependencyVersion> isAnUpgrade = (library,
+				candidate) -> library.getVersion().getVersion().isUpgrade(candidate, this.movingToSnapshots);
+		BiPredicate<Library, DependencyVersion> isPermitted = (library, candidate) -> {
+			for (ProhibitedVersion prohibitedVersion : library.getProhibitedVersions()) {
+				String candidateString = candidate.toString();
+				if (prohibitedVersion.getRange() != null
+						&& prohibitedVersion.getRange().containsVersion(new DefaultArtifactVersion(candidateString))) {
+					return false;
+				}
+				for (String startsWith : prohibitedVersion.getStartsWith()) {
+					if (candidateString.startsWith(startsWith)) {
+						return false;
+					}
+				}
+				for (String endsWith : prohibitedVersion.getEndsWith()) {
+					if (candidateString.endsWith(endsWith)) {
+						return false;
+					}
+				}
+				for (String contains : prohibitedVersion.getContains()) {
+					if (candidateString.contains(contains)) {
+						return false;
+					}
+				}
+			}
+			return true;
+		};
+		List<BiPredicate<Library, DependencyVersion>> updatePredicates = new ArrayList<>();
+		updatePredicates.add(compilesWithUpgradePolicy);
+		updatePredicates.add(isAnUpgrade);
+		updatePredicates.add(isPermitted);
+		return updatePredicates;
+	}
+
 	private List<Library> matchingLibraries() {
 		List<Library> matchingLibraries = this.bom.getLibraries().stream().filter(this::eligible).toList();
 		if (matchingLibraries.isEmpty()) {

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/github/Milestone.java

@@ -16,6 +16,8 @@
 
 package org.springframework.boot.build.bom.bomr.github;
 
+import java.time.OffsetDateTime;
+
 /**
  * A milestone in a {@link GitHubRepository GitHub repository}.
  *
@@ -27,9 +29,12 @@ public class Milestone {
 
 	private final int number;
 
-	Milestone(String name, int number) {
+	private final OffsetDateTime dueOn;
+
+	Milestone(String name, int number, OffsetDateTime dueOn) {
 		this.name = name;
 		this.number = number;
+		this.dueOn = dueOn;
 	}
 
 	/**
@@ -48,6 +53,10 @@ public class Milestone {
 		return this.number;
 	}
 
+	public OffsetDateTime getDueOn() {
+		return this.dueOn;
+	}
+
 	@Override
 	public String toString() {
 		return this.name + " (" + this.number + ")";

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/github/StandardGitHubRepository.java

@@ -17,6 +17,7 @@
 package org.springframework.boot.build.bom.bomr.github;
 
 import java.time.Duration;
+import java.time.OffsetDateTime;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
@@ -75,8 +76,9 @@ final class StandardGitHubRepository implements GitHubRepository {
 
 	@Override
 	public List<Milestone> getMilestones() {
-		return get("milestones?per_page=100",
-				(milestone) -> new Milestone((String) milestone.get("title"), (Integer) milestone.get("number")));
+		return get("milestones?per_page=100", (milestone) -> new Milestone((String) milestone.get("title"),
+				(Integer) milestone.get("number"),
+				(milestone.get("due_on") != null) ? OffsetDateTime.parse((String) milestone.get("due_on")) : null));
 	}
 
 	@Override

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/version/ArtifactVersionDependencyVersion.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2023 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.
@@ -87,24 +87,40 @@ class ArtifactVersionDependencyVersion extends AbstractDependencyVersion {
 		if (this.artifactVersion.equals(other)) {
 			return false;
 		}
-		if (this.artifactVersion.getMajorVersion() == other.getMajorVersion()
-				&& this.artifactVersion.getMinorVersion() == other.getMinorVersion()
-				&& this.artifactVersion.getIncrementalVersion() == other.getIncrementalVersion()) {
+		if (sameMajorMinorIncremental(other)) {
 			if (!StringUtils.hasLength(this.artifactVersion.getQualifier())
 					|| "RELEASE".equals(this.artifactVersion.getQualifier())) {
 				return false;
 			}
-			if ("SNAPSHOT".equals(this.artifactVersion.getQualifier())
-					|| "BUILD".equals(this.artifactVersion.getQualifier())) {
+			if (isSnapshot()) {
 				return true;
 			}
-			else if ("SNAPSHOT".equals(other.getQualifier()) || "BUILD".equals(other.getQualifier())) {
+			else if (((ArtifactVersionDependencyVersion) candidate).isSnapshot()) {
 				return movingToSnapshots;
 			}
 		}
 		return super.isUpgrade(candidate, movingToSnapshots);
 	}
 
+	private boolean sameMajorMinorIncremental(ArtifactVersion other) {
+		return this.artifactVersion.getMajorVersion() == other.getMajorVersion()
+				&& this.artifactVersion.getMinorVersion() == other.getMinorVersion()
+				&& this.artifactVersion.getIncrementalVersion() == other.getIncrementalVersion();
+	}
+
+	private boolean isSnapshot() {
+		return "SNAPSHOT".equals(this.artifactVersion.getQualifier())
+				|| "BUILD".equals(this.artifactVersion.getQualifier());
+	}
+
+	@Override
+	public boolean isSnapshotFor(DependencyVersion candidate) {
+		if (!isSnapshot() || !(candidate instanceof ArtifactVersionDependencyVersion)) {
+			return false;
+		}
+		return sameMajorMinorIncremental(((ArtifactVersionDependencyVersion) candidate).artifactVersion);
+	}
+
 	@Override
 	public String toString() {
 		return this.artifactVersion.toString();

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/version/DependencyVersion.java

@@ -46,13 +46,21 @@ public interface DependencyVersion extends Comparable<DependencyVersion> {
 
 	/**
 	 * Returns whether the given {@code candidate} is an upgrade of this version.
-	 * @param candidate the version the consider
+	 * @param candidate the version to consider
 	 * @param movingToSnapshots whether the upgrade is to be considered as part of moving
 	 * to snaphots
 	 * @return {@code true} if the candidate is an upgrade, otherwise false
 	 */
 	boolean isUpgrade(DependencyVersion candidate, boolean movingToSnapshots);
 
+	/**
+	 * Returns whether this version is a snapshot for the given {@code candidate}.
+	 * @param candidate the version to consider
+	 * @return {@code true} if this version is a snapshot for the candidate, otherwise
+	 * false
+	 */
+	boolean isSnapshotFor(DependencyVersion candidate);
+
 	static DependencyVersion parse(String version) {
 		List<Function<String, DependencyVersion>> parsers = Arrays.asList(CalendarVersionDependencyVersion::parse,
 				ArtifactVersionDependencyVersion::parse, ReleaseTrainDependencyVersion::parse,

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/version/ReleaseTrainDependencyVersion.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2022 the original author or authors.
+ * Copyright 2012-2023 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.
@@ -72,8 +72,7 @@ final class ReleaseTrainDependencyVersion implements DependencyVersion {
 		if (comparison != 0) {
 			return comparison < 0;
 		}
-		if (movingToSnapshots && !"BUILD-SNAPSHOT".equals(this.type)
-				&& "BUILD-SNAPSHOT".equals(candidateReleaseTrain.type)) {
+		if (movingToSnapshots && !isSnapshot() && candidateReleaseTrain.isSnapshot()) {
 			return true;
 		}
 		comparison = this.type.compareTo(candidateReleaseTrain.type);
@@ -83,6 +82,19 @@ final class ReleaseTrainDependencyVersion implements DependencyVersion {
 		return Integer.compare(this.version, candidateReleaseTrain.version) < 0;
 	}
 
+	private boolean isSnapshot() {
+		return "BUILD-SNAPSHOT".equals(this.type);
+	}
+
+	@Override
+	public boolean isSnapshotFor(DependencyVersion candidate) {
+		if (!isSnapshot() || !(candidate instanceof ReleaseTrainDependencyVersion)) {
+			return false;
+		}
+		ReleaseTrainDependencyVersion candidateReleaseTrain = (ReleaseTrainDependencyVersion) candidate;
+		return this.releaseTrain.equals(candidateReleaseTrain.releaseTrain);
+	}
+
 	@Override
 	public boolean isSameMajor(DependencyVersion other) {
 		return isSameReleaseTrain(other);

buildSrc/src/main/java/org/springframework/boot/build/bom/bomr/version/UnstructuredDependencyVersion.java

@@ -48,6 +48,11 @@ final class UnstructuredDependencyVersion extends AbstractDependencyVersion impl
 		return this.version;
 	}
 
+	@Override
+	public boolean isSnapshotFor(DependencyVersion candidate) {
+		return false;
+	}
+
 	static UnstructuredDependencyVersion parse(String version) {
 		return new UnstructuredDependencyVersion(version);
 	}