use ConcurrentHashMap instead of plain HashMap
package org.apache.wiki.workflow;
import java.security.Principal;
-import java.util.HashMap;
import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
import org.apache.wiki.WikiEngine;
import org.apache.wiki.api.exceptions.WikiException;
@@ -30,7 +30,7 @@ import org.apache.wiki.api.exceptions.WikiException;
*/
public final class WorkflowBuilder
{
- private static final Map<WikiEngine, WorkflowBuilder> BUILDERS = new HashMap<WikiEngine, WorkflowBuilder>();
+ private static final Map<WikiEngine, WorkflowBuilder> BUILDERS = new ConcurrentHashMap<>();
private final WikiEngine m_engine;
/**
