Improve javadoc cleanup to remove duplicate spaces

Improve `TypeUtils` so that repeated space chars are removed.

Fixes gh-40593

Author: philwebb

spring-boot-project/spring-boot-tools/spring-boot-configuration-processor/src/main/java/org/springframework/boot/configurationprocessor/TypeUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2023 the original author or authors.
+ * Copyright 2012-2024 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.
@@ -67,8 +67,6 @@ class TypeUtils {
 
 	private static final Map<String, TypeKind> WRAPPER_TO_PRIMITIVE;
 
-	private static final Pattern NEW_LINE_PATTERN = Pattern.compile("[\r\n]+");
-
 	static {
 		Map<String, TypeKind> primitives = new HashMap<>();
 		PRIMITIVE_WRAPPERS.forEach((kind, wrapperClass) -> primitives.put(wrapperClass.getName(), kind));
@@ -183,9 +181,7 @@ String getJavaDoc(Element element) {
 			return getJavaDoc((RecordComponentElement) element);
 		}
 		String javadoc = (element != null) ? this.env.getElementUtils().getDocComment(element) : null;
-		if (javadoc != null) {
-			javadoc = NEW_LINE_PATTERN.matcher(javadoc).replaceAll("").trim();
-		}
+		javadoc = (javadoc != null) ? cleanupJavaDoc(javadoc) : null;
 		return (javadoc == null || javadoc.isEmpty()) ? null : javadoc;
 	}
 
@@ -259,7 +255,7 @@ private String getJavaDoc(RecordComponentElement recordComponent) {
 			Pattern paramJavadocPattern = paramJavadocPattern(recordComponent.getSimpleName().toString());
 			Matcher paramJavadocMatcher = paramJavadocPattern.matcher(recordJavadoc);
 			if (paramJavadocMatcher.find()) {
-				String paramJavadoc = NEW_LINE_PATTERN.matcher(paramJavadocMatcher.group()).replaceAll("").trim();
+				String paramJavadoc = cleanupJavaDoc(paramJavadocMatcher.group());
 				return paramJavadoc.isEmpty() ? null : paramJavadoc;
 			}
 		}
@@ -271,6 +267,20 @@ private Pattern paramJavadocPattern(String paramName) {
 		return Pattern.compile(pattern, Pattern.DOTALL);
 	}
 
+	private String cleanupJavaDoc(String javadoc) {
+		StringBuilder result = new StringBuilder(javadoc.length());
+		char lastChar = '.';
+		for (int i = 0; i < javadoc.length(); i++) {
+			char ch = javadoc.charAt(i);
+			boolean repeatedSpace = ch == ' ' && lastChar == ' ';
+			if (ch != '\r' && ch != '\n' && !repeatedSpace) {
+				result.append(ch);
+				lastChar = ch;
+			}
+		}
+		return result.toString().trim();
+	}
+
 	/**
 	 * A visitor that extracts the fully qualified name of a type, including generic
 	 * information.

spring-boot-project/spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationprocessor/ConfigurationMetadataAnnotationProcessorTests.java

@@ -521,7 +521,7 @@ void shouldNotMarkDbcp2UsernameOrPasswordAsDeprecated() {
 	void recordPropertiesWithDescriptions() {
 		ConfigurationMetadata metadata = compile(ExampleRecord.class);
 		assertThat(metadata).has(Metadata.withProperty("record.descriptions.some-string", String.class)
-			.withDescription("very long description that doesn't fit single line"));
+			.withDescription("very long description that doesn't fit single line and is indented"));
 		assertThat(metadata).has(Metadata.withProperty("record.descriptions.some-integer", Integer.class)
 			.withDescription("description with @param and @ pitfalls"));
 		assertThat(metadata).has(Metadata.withProperty("record.descriptions.some-boolean", Boolean.class)

spring-boot-project/spring-boot-tools/spring-boot-configuration-processor/src/test/java/org/springframework/boot/configurationsample/record/ExampleRecord.java

@@ -16,10 +16,13 @@
 
 package org.springframework.boot.configurationsample.record;
 
+// @formatter:off
+
 /**
  * Example Record Javadoc sample
  *
- * @param someString very long description that doesn't fit single line
+ * @param someString very long description that
+ *                   doesn't fit single line and is indented
  * @param someInteger description with @param and @ pitfalls
  * @param someBoolean description with extra spaces
  * @param someLong description without space after asterisk
@@ -30,3 +33,5 @@
 @org.springframework.boot.configurationsample.ConfigurationProperties("record.descriptions")
 public record ExampleRecord(String someString, Integer someInteger, Boolean someBoolean, Long someLong, Byte someByte) {
 }
+
+//@formatter:on

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/TempTests.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2012-2024 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.context.properties;
+
+/**
+ * @author pwebb
+ */
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.boot.context.properties.bind.DefaultValue;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.test.context.support.TestPropertySourceUtils;
+
+public class TempTests {
+
+	private AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+
+	@Test
+	void testName() {
+		load(MyConfig.class, "foo.bar.baz=hello");
+		System.out.println(this.context.getBean(Foo.class));
+	}
+
+	@Test
+	void testName2() {
+		load(MyConfig.class);
+		System.out.println(this.context.getBean(Foo.class));
+	}
+
+	private AnnotationConfigApplicationContext load(Class<?> configuration, String... inlinedProperties) {
+		return load(new Class<?>[] { configuration }, inlinedProperties);
+	}
+
+	private AnnotationConfigApplicationContext load(Class<?>[] configuration, String... inlinedProperties) {
+		this.context.register(configuration);
+		TestPropertySourceUtils.addInlinedPropertiesToEnvironment(this.context, inlinedProperties);
+		this.context.refresh();
+		return this.context;
+	}
+
+	@Configuration
+	@EnableConfigurationProperties(Foo.class)
+	static class MyConfig {
+
+	}
+
+	@ConfigurationProperties("foo")
+	record Foo(@DefaultValue Bar bar) {
+	}
+
+	record Bar(@DefaultValue("hello") String baz) {
+	}
+
+}