Use toLowerCase() and toUpperCase() with Locale.ENGLISH

This commit updates all `toLowerCase()` and `toUpperCase` invocations to
use the variant that takes a `Locale` to avoid locale-specific side
effect.

Closes gh-12213

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/cloudfoundry/CloudFoundrySecurityInterceptor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -16,6 +16,8 @@
 
 package org.springframework.boot.actuate.cloudfoundry;
 
+import java.util.Locale;
+
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
@@ -107,7 +109,7 @@ class CloudFoundrySecurityInterceptor extends HandlerInterceptorAdapter {
 		String authorization = request.getHeader("Authorization");
 		String bearerPrefix = "bearer ";
 		if (authorization == null
-				|| !authorization.toLowerCase().startsWith(bearerPrefix)) {
+				|| !authorization.toLowerCase(Locale.ENGLISH).startsWith(bearerPrefix)) {
 			throw new CloudFoundryAuthorizationException(Reason.MISSING_AUTHORIZATION,
 					"Authorization header is missing or invalid");
 		}

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/DataSourcePublicMetrics.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -19,6 +19,7 @@ package org.springframework.boot.actuate.endpoint;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.LinkedHashSet;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 
@@ -104,7 +105,7 @@ public class DataSourcePublicMetrics implements PublicMetrics {
 			return "datasource.primary";
 		}
 		if (name.length() > DATASOURCE_SUFFIX.length()
-				&& name.toLowerCase().endsWith(DATASOURCE_SUFFIX.toLowerCase())) {
+				&& name.toLowerCase(Locale.ENGLISH).endsWith(DATASOURCE_SUFFIX.toLowerCase())) {
 			name = name.substring(0, name.length() - DATASOURCE_SUFFIX.length());
 		}
 		return "datasource." + name;

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/HealthEndpoint.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -16,6 +16,7 @@
 
 package org.springframework.boot.actuate.endpoint;
 
+import java.util.Locale;
 import java.util.Map;
 
 import org.springframework.boot.actuate.health.CompositeHealthIndicator;
@@ -91,7 +92,7 @@ public class HealthEndpoint extends AbstractEndpoint<Health> {
 	 * @return the key
 	 */
 	private String getKey(String name) {
-		int index = name.toLowerCase().indexOf("healthindicator");
+		int index = name.toLowerCase(Locale.ENGLISH).indexOf("healthindicator");
 		if (index > 0) {
 			return name.substring(0, index);
 		}

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/SystemPublicMetrics.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2015 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -24,6 +24,7 @@ import java.lang.management.ThreadMXBean;
 import java.util.Collection;
 import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Locale;
 
 import org.springframework.boot.actuate.metrics.Metric;
 import org.springframework.core.Ordered;
@@ -188,7 +189,7 @@ public class SystemPublicMetrics implements PublicMetrics, Ordered {
 	 * @return a metric friendly name
 	 */
 	private String beautifyGcName(String name) {
-		return StringUtils.replace(name, " ", "_").toLowerCase();
+		return StringUtils.replace(name, " ", "_").toLowerCase(Locale.ENGLISH);
 	}
 
 }

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/jmx/LoggersEndpointMBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -16,6 +16,8 @@
 
 package org.springframework.boot.actuate.endpoint.jmx;
 
+import java.util.Locale;
+
 import com.fasterxml.jackson.databind.ObjectMapper;
 
 import org.springframework.boot.actuate.endpoint.Endpoint;
@@ -52,7 +54,7 @@ public class LoggersEndpointMBean extends EndpointMBean {
 	@ManagedOperation(description = "Set log level for a given logger")
 	public void setLogLevel(String loggerName, String logLevel) {
 		Assert.notNull(logLevel, "LogLevel must not be null");
-		LogLevel level = LogLevel.valueOf(logLevel.toUpperCase());
+		LogLevel level = LogLevel.valueOf(logLevel.toUpperCase(Locale.ENGLISH));
 		getEndpoint().setLogLevel(loggerName, level);
 	}
 

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/HealthMvcEndpoint.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -20,6 +20,7 @@ import java.security.Principal;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 
 import javax.servlet.http.HttpServletRequest;
@@ -151,7 +152,7 @@ public class HealthMvcEndpoint extends AbstractEndpointMvcAdapter<HealthEndpoint
 	private HttpStatus getStatus(Health health) {
 		String code = health.getStatus().getCode();
 		if (code != null) {
-			code = code.toLowerCase().replace('_', '-');
+			code = code.toLowerCase(Locale.ENGLISH).replace('_', '-');
 			for (String candidate : RelaxedNames.forCamelCase(code)) {
 				HttpStatus status = this.statusMapping.get(candidate);
 				if (status != null) {

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/endpoint/mvc/LoggersMvcEndpoint.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -16,6 +16,7 @@
 
 package org.springframework.boot.actuate.endpoint.mvc;
 
+import java.util.Locale;
 import java.util.Map;
 
 import org.springframework.boot.actuate.endpoint.LoggersEndpoint;
@@ -78,7 +79,8 @@ public class LoggersMvcEndpoint extends EndpointMvcAdapter {
 	private LogLevel getLogLevel(Map<String, String> configuration) {
 		String level = configuration.get("configuredLevel");
 		try {
-			return (level == null ? null : LogLevel.valueOf(level.toUpperCase()));
+			return (level == null ? null
+					: LogLevel.valueOf(level.toUpperCase(Locale.ENGLISH)));
 		}
 		catch (IllegalArgumentException ex) {
 			throw new InvalidLogLevelException(level);

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/trace/WebRequestTraceFilter.java

@@ -23,6 +23,7 @@ import java.util.Enumeration;
 import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
@@ -165,7 +166,7 @@ public class WebRequestTraceFilter extends OncePerRequestFilter implements Order
 		Enumeration<String> names = request.getHeaderNames();
 		while (names.hasMoreElements()) {
 			String name = names.nextElement();
-			if (!excludedHeaders.contains(name.toLowerCase())) {
+			if (!excludedHeaders.contains(name.toLowerCase(Locale.ENGLISH))) {
 				headers.put(name, getHeaderValue(request, name));
 			}
 		}