[tomcat] branch 8.5.x updated: Fix locking - found by SpotBugs

[markt]

This is an automated email from the ASF dual-hosted git repository.

markt pushed a commit to branch 8.5.x
in repository https://gitbox.apache.org/repos/asf/tomcat.git


The following commit(s) were added to refs/heads/8.5.x by this push:
     new 72a46ed4c1 Fix locking - found by SpotBugs
72a46ed4c1 is described below

commit 72a46ed4c1471fcdf09d0946af7ffa381f320060
Author: Mark Thomas <ma...@apache.org>
AuthorDate: Mon Sep 12 10:00:40 2022 +0100

    Fix locking - found by SpotBugs
---
 java/org/apache/catalina/realm/MemoryRealm.java | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

diff --git a/java/org/apache/catalina/realm/MemoryRealm.java 
b/java/org/apache/catalina/realm/MemoryRealm.java
index 1e6593f3f4..fa7f9a83d2 100644
--- a/java/org/apache/catalina/realm/MemoryRealm.java
+++ b/java/org/apache/catalina/realm/MemoryRealm.java
@@ -53,6 +53,7 @@ public class MemoryRealm  extends RealmBase {
      * The Digester we will use to process in-memory database files.
      */
     private static Digester digester = null;
+    private static final Object digesterLock = new Object();
 
 
     /**
@@ -194,18 +195,18 @@ public class MemoryRealm  extends RealmBase {
      * @return a configured <code>Digester</code> to use for processing
      * the XML input file, creating a new one if necessary.
      */
-    protected synchronized Digester getDigester() {
-        if (digester == null) {
-            digester = new Digester();
-            digester.setValidating(false);
-            try {
-                digester.setFeature(
-                        "http://apache.org/xml/features/allow-java-encodings";,
-                        true);
-            } catch (Exception e) {
-                log.warn(sm.getString("memoryRealm.xmlFeatureEncoding"), e);
+    protected Digester getDigester() {
+        synchronized (digesterLock) {
+            if (digester == null) {
+                digester = new Digester();
+                digester.setValidating(false);
+                try {
+                    
digester.setFeature("http://apache.org/xml/features/allow-java-encodings";, 
true);
+                } catch (Exception e) {
+                    log.warn(sm.getString("memoryRealm.xmlFeatureEncoding"), 
e);
+                }
+                digester.addRuleSet(new MemoryRuleSet());
             }
-            digester.addRuleSet(new MemoryRuleSet());
         }
         return digester;
     }


---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org
For additional commands, e-mail: dev-h...@tomcat.apache.org