Use a templated source file for SpringBootVersion

Closes gh-29670

spring-boot-project/spring-boot/build.gradle

@@ -155,7 +155,26 @@ task extractTomcatConfigProperties(type: Sync) {
 	}
 }
 
+def syncJavaTemplates = tasks.register("syncJavaTemplates", Sync) {
+	from("src/main/javaTemplates")
+	into("build/generated-sources/main")
+	def properties = ["springBootVersion": project.version]
+	expand(properties)
+	inputs.properties(properties)
+}
+
+plugins.withType(EclipsePlugin) {
+	eclipse {
+		synchronizationTasks syncJavaTemplates
+	}
+}
+
 sourceSets {
+	main {
+		java {
+			srcDirs syncJavaTemplates
+		}
+	}
 	test {
 		output.dir(tomcatConfigProperties, builtBy: "extractTomcatConfigProperties")
 	}

spring-boot-project/spring-boot/src/main/javaTemplates/org/springframework/boot/SpringBootVersion.java

@@ -16,18 +16,9 @@
 
 package org.springframework.boot;
 
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.Properties;
-
 /**
  * Exposes the Spring Boot version.
  *
- * The version information is read from a file that is stored in the Spring Boot library.
- * If the version information cannot be read from the file, consider using a
- * reflection-based check instead (for example, checking for the presence of a specific
- * Spring Boot method that you intend to call).
- *
  * @author Drummond Dawson
  * @author Hendrig Sellik
  * @author Andy Wilkinson
@@ -40,24 +31,11 @@ public final class SpringBootVersion {
 	}
 
 	/**
-	 * Return the full version string of the present Spring Boot codebase, or {@code null}
-	 * if it cannot be determined.
-	 * @return the version of Spring Boot or {@code null}
+	 * Return the full version string of the present Spring Boot codebase.
+	 * @return the version of Spring Boot
 	 */
 	public static String getVersion() {
-		InputStream input = SpringBootVersion.class.getClassLoader()
-				.getResourceAsStream("META-INF/spring-boot.properties");
-		if (input != null) {
-			try {
-				Properties properties = new Properties();
-				properties.load(input);
-				return properties.getProperty("version");
-			}
-			catch (IOException ex) {
-				// fall through
-			}
-		}
-		return null;
+		return "${springBootVersion}";
 	}
 
 }

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/SpringBootVersionTests.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2012-2022 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;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.core.io.support.PropertiesLoaderUtils;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link SpringBootVersion}.
+ *
+ * @author Andy Wilkinson
+ */
+public class SpringBootVersionTests {
+
+	@Test
+	void getVersionShouldReturnVersionMatchingGradleProperties() throws IOException {
+		String expectedVersion = PropertiesLoaderUtils.loadProperties(new FileSystemResource(findGradleProperties()))
+				.getProperty("version");
+		assertThat(SpringBootVersion.getVersion()).isEqualTo(expectedVersion);
+	}
+
+	private File findGradleProperties() {
+		File current = new File(".").getAbsoluteFile();
+		while (current != null) {
+			File gradleProperties = new File(current, "gradle.properties");
+			System.out.println(gradleProperties);
+			if (gradleProperties.isFile()) {
+				return gradleProperties;
+			}
+			current = current.getParentFile();
+		}
+		throw new IllegalStateException("Could not find gradle.properties");
+	}
+
+}