Avoid using immutable collections for configuration proprerties

Closes gh-8620

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/elasticsearch/jest/JestProperties.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -16,7 +16,8 @@
 
 package org.springframework.boot.autoconfigure.elasticsearch.jest;
 
-import java.util.Arrays;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -33,7 +34,8 @@ public class JestProperties {
 	/**
 	 * Comma-separated list of the Elasticsearch instances to use.
 	 */
-	private List<String> uris = Arrays.asList("http://localhost:9200");
+	private List<String> uris = new ArrayList<String>(
+			Collections.singletonList("http://localhost:9200"));
 
 	/**
 	 * Login user.

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/flyway/FlywayProperties.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -17,7 +17,6 @@
 package org.springframework.boot.autoconfigure.flyway;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
@@ -40,7 +39,8 @@ public class FlywayProperties {
 	/**
 	 * Locations of migrations scripts.
 	 */
-	private List<String> locations = new ArrayList<String>(Arrays.asList("db/migration"));
+	private List<String> locations = new ArrayList<String>(
+			Collections.singletonList("db/migration"));
 
 	/**
 	 * Check that migration scripts location exists.
@@ -72,7 +72,7 @@ public class FlywayProperties {
 	 * SQL statements to execute to initialize a connection immediately after obtaining
 	 * it.
 	 */
-	private List<String> initSqls = Collections.emptyList();
+	private List<String> initSqls = new ArrayList<String>();
 
 	public void setLocations(List<String> locations) {
 		this.locations = locations;

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/security/SecurityProperties.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.
@@ -17,7 +17,7 @@
 package org.springframework.boot.autoconfigure.security;
 
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 import java.util.UUID;
@@ -314,7 +314,8 @@ public class SecurityProperties implements SecurityPrerequisite {
 		/**
 		 * Granted roles for the default user name.
 		 */
-		private List<String> role = new ArrayList<String>(Arrays.asList("USER"));
+		private List<String> role = new ArrayList<String>(
+				Collections.singletonList("USER"));
 
 		private boolean defaultPassword = true;
 

spring-boot/src/main/java/org/springframework/boot/jta/narayana/NarayanaProperties.java

 /*
- * Copyright 2012-2016 the original author or authors.
+ * Copyright 2012-2017 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.jta.narayana;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -90,22 +91,22 @@ public class NarayanaProperties {
 	/**
 	 * Comma-separated list of orphan filters.
 	 */
-	private List<String> xaResourceOrphanFilters = Arrays.asList(
+	private List<String> xaResourceOrphanFilters = new ArrayList<String>(Arrays.asList(
 			"com.arjuna.ats.internal.jta.recovery.arjunacore.JTATransactionLogXAResourceOrphanFilter",
-			"com.arjuna.ats.internal.jta.recovery.arjunacore.JTANodeNameXAResourceOrphanFilter");
+			"com.arjuna.ats.internal.jta.recovery.arjunacore.JTANodeNameXAResourceOrphanFilter"));
 
 	/**
 	 * Comma-separated list of recovery modules.
 	 */
-	private List<String> recoveryModules = Arrays.asList(
+	private List<String> recoveryModules = new ArrayList<String>(Arrays.asList(
 			"com.arjuna.ats.internal.arjuna.recovery.AtomicActionRecoveryModule",
-			"com.arjuna.ats.internal.jta.recovery.arjunacore.XARecoveryModule");
+			"com.arjuna.ats.internal.jta.recovery.arjunacore.XARecoveryModule"));
 
 	/**
 	 * Comma-separated list of expiry scanners.
 	 */
-	private List<String> expiryScanners = Collections.singletonList(
-			"com.arjuna.ats.internal.arjuna.recovery.ExpiredTransactionStatusManagerScanner");
+	private List<String> expiryScanners = new ArrayList<String>(Collections.singletonList(
+			"com.arjuna.ats.internal.arjuna.recovery.ExpiredTransactionStatusManagerScanner"));
 
 	public String getLogDir() {
 		return this.logDir;