From 89a4255679dea014a8c06808225a38c89de16956 Mon Sep 17 00:00:00 2001
From: Christoph Dreis <christoph.dreis@freenet.de>
Date: Thu, 17 Oct 2019 19:29:28 +0200
Subject: [PATCH] Parse expression only once in PrincipalNameIndexResolver

Resolves: #1539
---
 .../springframework/session/PrincipalNameIndexResolver.java    | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/spring-session-core/src/main/java/org/springframework/session/PrincipalNameIndexResolver.java b/spring-session-core/src/main/java/org/springframework/session/PrincipalNameIndexResolver.java
index 868aae50..f4d7e87b 100644
--- a/spring-session-core/src/main/java/org/springframework/session/PrincipalNameIndexResolver.java
+++ b/spring-session-core/src/main/java/org/springframework/session/PrincipalNameIndexResolver.java
@@ -32,7 +32,7 @@ public class PrincipalNameIndexResolver<S extends Session> extends SingleIndexRe
 
 	private static final String SPRING_SECURITY_CONTEXT = "SPRING_SECURITY_CONTEXT";
 
-	private static final SpelExpressionParser parser = new SpelExpressionParser();
+	private static final Expression expression = new SpelExpressionParser().parseExpression("authentication?.name");
 
 	public PrincipalNameIndexResolver() {
 		super(FindByIndexNameSessionRepository.PRINCIPAL_NAME_INDEX_NAME);
@@ -45,7 +45,6 @@ public class PrincipalNameIndexResolver<S extends Session> extends SingleIndexRe
 		}
 		Object authentication = session.getAttribute(SPRING_SECURITY_CONTEXT);
 		if (authentication != null) {
-			Expression expression = parser.parseExpression("authentication?.name");
 			return expression.getValue(authentication, String.class);
 		}
 		return null;