Ban certain javadoc tags

Closes gh-190

Author: philwebb

spring-javaformat/spring-javaformat-checkstyle/src/main/java/io/spring/javaformat/checkstyle/check/SpringJavadocCheck.java

@@ -44,6 +44,13 @@ public class SpringJavadocCheck extends AbstractSpringCheck {
 		CASE_CHECKED_TAG_PATTERNS = Collections.unmodifiableList(patterns);
 	}
 
+	private static final List<Pattern> BANNED_TAGS;
+	static {
+		List<Pattern> patterns = new ArrayList<>();
+		patterns.add(Pattern.compile("(@soundtrack)\\s+.*"));
+		BANNED_TAGS = Collections.unmodifiableList(patterns);
+	}
+
 	private static final Pattern SINCE_TAG_PATTERN = Pattern.compile("@since\\s+(.*)");
 
 	private static final Set<Integer> TOP_LEVEL_TYPES;
@@ -78,8 +85,26 @@ public void visitToken(DetailAST ast) {
 		int lineNumber = ast.getLineNo();
 		TextBlock javadoc = getFileContents().getJavadocBefore(lineNumber);
 		if (javadoc != null) {
-			checkTagCase(ast, javadoc);
-			checkSinceTag(ast, javadoc);
+			checkJavadoc(ast, javadoc);
+		}
+	}
+
+	private void checkJavadoc(DetailAST ast, TextBlock javadoc) {
+		checkBannedTags(ast, javadoc);
+		checkTagCase(ast, javadoc);
+		checkSinceTag(ast, javadoc);
+	}
+
+	private void checkBannedTags(DetailAST ast, TextBlock javadoc) {
+		String[] text = javadoc.getText();
+		for (int i = 0; i < text.length; i++) {
+			for (Pattern pattern : BANNED_TAGS) {
+				Matcher matcher = pattern.matcher(text[i]);
+				if (matcher.find()) {
+					String tagName = matcher.group(1).trim();
+					log(javadoc.getStartLineNo() + i, tagName.length(), "javadoc.bannedTag", tagName);
+				}
+			}
 		}
 	}
 

spring-javaformat/spring-javaformat-checkstyle/src/main/resources/io/spring/javaformat/checkstyle/check/messages.properties

@@ -3,6 +3,7 @@ catch.wideEye=''o_O'' catch variable (use "ex" instead).
 header.unexpected=Unexpected header.
 header.mismatch=Line does not match expected header line of ''{0}''.
 javadoc.badCase=Javadoc element descriptions should not start with an uppercase letter.
+javadoc.bannedTag=Javadoc tag ''{0}'' should not be used.
 javadoc.missingSince=Missing Javadoc @since tag.
 javadoc.publicSince=Javadoc @since tag should not be used on private classes.
 junit5.bannedImport=Import ''{0}'' should not be used in a JUnit 5 test.

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/check/JavadocSoundtrack.txt

@@ -0,0 +1 @@
++Javadoc tag '@soundtrack' should not be used. [SpringJavadoc]

spring-javaformat/spring-javaformat-checkstyle/src/test/resources/source/JavadocSoundtrack.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2017-2019 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.
+ */
+
+/**
+ * Valid Javadoc.
+ *
+ * @param <T> this is a valid param
+ * @author Phillip Webb
+ * @soundtrack Gina G - Ooh Aah Just A Little Bit
+ */
+public class JavadocSoundtrack<T> {
+
+}