Update copyright task

CONTRIBUTING.adoc

@@ -79,7 +79,7 @@ See https://github.com/spring-projects/spring-security/tree/main#building-from-s
 
 The wiki pages https://github.com/spring-projects/spring-framework/wiki/Code-Style[Code Style] and https://github.com/spring-projects/spring-framework/wiki/IntelliJ-IDEA-Editor-Settings[IntelliJ IDEA Editor Settings] define the source file coding standards we use along with some IDEA editor settings we customize.
 
-To format the code as well as check the style, run `./gradlew format && ./gradlew check`.
+To format the code as well as check the style, run `./gradlew format && ./gradlew updateCopyrights && ./gradlew check`.
 
 [[submit-a-pull-request]]
 === Submit a Pull Request
@@ -104,7 +104,7 @@ If this is for an issue, consider a branch name with the issue number, like `gh-
 6. [[update-copyright]] In all files you edited, if the copyright header is of the form 2002-20xx, update the final copyright year to the current year.
 7. [[add-since]] If on `main`, add `@since` JavaDoc attributes to new public APIs that your PR adds
 8. [[change-rnc]] If you are updating the XSD, please instead update the RNC file and then run `./gradlew :spring-security-config:rncToXsd`.
-9. [[format-code]] For each commit, build the code using `./gradlew format && ./gradlew check`.
+9. [[format-code]] For each commit, build the code using `./gradlew format && ./gradlew updateCopyrights && ./gradlew check`.
 This command ensures the code meets most of <<code-style,the style guide>>; a notable exception is import order.
 10. [[commit-atomically]] Choose the granularity of your commits consciously and squash commits that represent
 multiple edits or corrections of the same logical change.

build.gradle

@@ -120,6 +120,32 @@ tasks.register('cloneRepository', IncludeRepoTask) {
 	outputDirectory = project.hasProperty("cloneOutputDirectory") ? project.file("$cloneOutputDirectory") : defaultDirectory
 }
 
+tasks.register('updateCopyrights') {
+
+	def now = Calendar.instance.get(Calendar.YEAR) as String
+	def branch = project.hasProperty("branch") ? project.property("branch") : "origin/main"
+	def gitOutput = ["git", "diff", "--diff-filter=M", "--name-only", branch, "--", "*.java"].execute().text
+	gitOutput.readLines()
+			.collect { new File(it) }
+			.each { file ->
+				def line
+				file.withReader { reader ->
+					while (line = reader.readLine()) {
+						def matcher = line =~ /Copyright (20\d\d)-?(20\d\d)? the original author or authors.$/
+						if (matcher.count) {
+							def beginningYear = matcher[0][1]
+							if (now != beginningYear && now != matcher[0][2]) {
+								def sourceCode = file.getText('UTF-8')
+								sourceCode = sourceCode.replaceFirst(/20\d\d(-20\d\d)?/, "$beginningYear-$now")
+								file.text = sourceCode
+								println "Update copyright for file: $file"
+							}
+						}
+					}
+				}
+			}
+}
+
 wrapperUpgrade {
 	gradle {
 		'spring-security' {