Avoid creation of unused logger instance in AbstractMediaTypeExpression

Closes gh-25901

spring-webflux/src/main/java/org/springframework/web/reactive/result/condition/AbstractMediaTypeExpression.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -16,9 +16,6 @@
 
 package org.springframework.web.reactive.result.condition;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
 import org.springframework.http.MediaType;
 import org.springframework.lang.Nullable;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -35,8 +32,6 @@ import org.springframework.web.server.UnsupportedMediaTypeStatusException;
  */
 abstract class AbstractMediaTypeExpression implements Comparable<AbstractMediaTypeExpression>, MediaTypeExpression {
 
-	protected final Log logger = LogFactory.getLog(getClass());
-
 	private final MediaType mediaType;
 
 	private final boolean isNegated;
@@ -108,12 +103,10 @@ abstract class AbstractMediaTypeExpression implements Comparable<AbstractMediaTy
 
 	@Override
 	public String toString() {
-		StringBuilder builder = new StringBuilder();
 		if (this.isNegated) {
-			builder.append('!');
+			return '!' + this.mediaType.toString();
 		}
-		builder.append(this.mediaType.toString());
+		return this.mediaType.toString();
-		return builder.toString();
 	}
 
 }

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/condition/AbstractMediaTypeExpression.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 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.
@@ -16,9 +16,6 @@
 
 package org.springframework.web.servlet.mvc.condition;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
 import org.springframework.http.MediaType;
 import org.springframework.lang.Nullable;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -33,8 +30,6 @@ import org.springframework.web.bind.annotation.RequestMapping;
  */
 abstract class AbstractMediaTypeExpression implements MediaTypeExpression, Comparable<AbstractMediaTypeExpression> {
 
-	protected final Log logger = LogFactory.getLog(getClass());
-
 	private final MediaType mediaType;
 
 	private final boolean isNegated;
@@ -92,12 +87,10 @@ abstract class AbstractMediaTypeExpression implements MediaTypeExpression, Compa
 
 	@Override
 	public String toString() {
-		StringBuilder builder = new StringBuilder();
 		if (this.isNegated) {
-			builder.append('!');
+			return '!' + this.mediaType.toString();
 		}
-		builder.append(this.mediaType.toString());
+		return this.mediaType.toString();
-		return builder.toString();
 	}
 
 }