From 9674ce490670b3d80018c8717eced2babb284e0d Mon Sep 17 00:00:00 2001 From: Juergen Hoeller Date: Sat, 4 May 2019 12:00:22 +0200 Subject: [PATCH] Avoid HashSet/StringBuilder allocation for non-placeholder values Closes gh-22870 --- .../util/PropertyPlaceholderHelper.java | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java b/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java index b80ded1bb6..b17d6f85fd 100644 --- a/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java +++ b/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java @@ -1,5 +1,5 @@ /* - * Copyright 2002-2017 the original author or authors. + * Copyright 2002-2019 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. @@ -121,20 +121,26 @@ public class PropertyPlaceholderHelper { */ public String replacePlaceholders(String value, PlaceholderResolver placeholderResolver) { Assert.notNull(value, "'value' must not be null"); - return parseStringValue(value, placeholderResolver, new HashSet<>()); + return parseStringValue(value, placeholderResolver, null); } protected String parseStringValue( - String value, PlaceholderResolver placeholderResolver, Set visitedPlaceholders) { - - StringBuilder result = new StringBuilder(value); + String value, PlaceholderResolver placeholderResolver, @Nullable Set visitedPlaceholders) { int startIndex = value.indexOf(this.placeholderPrefix); + if (startIndex == -1) { + return value; + } + + StringBuilder result = new StringBuilder(value); while (startIndex != -1) { int endIndex = findPlaceholderEndIndex(result, startIndex); if (endIndex != -1) { String placeholder = result.substring(startIndex + this.placeholderPrefix.length(), endIndex); String originalPlaceholder = placeholder; + if (visitedPlaceholders == null) { + visitedPlaceholders = new HashSet<>(4); + } if (!visitedPlaceholders.add(originalPlaceholder)) { throw new IllegalArgumentException( "Circular placeholder reference '" + originalPlaceholder + "' in property definitions"); @@ -178,7 +184,6 @@ public class PropertyPlaceholderHelper { startIndex = -1; } } - return result.toString(); }