[jboss-cvs] JBossAS SVN: r97193 - projects/logging-service-metadata/trunk/src/main/java/org/jboss/logging/metadata.

[jboss-cvs-commits at lists.jboss.org]

Author: david.lloyd at jboss.com
Date: 2009-11-30 20:02:25 -0500 (Mon, 30 Nov 2009)
New Revision: 97193

Added:
   projects/logging-service-metadata/trunk/src/main/java/org/jboss/logging/metadata/LogContextRegistry.java
Log:
Simple name-keyed log context registry

Added: projects/logging-service-metadata/trunk/src/main/java/org/jboss/logging/metadata/LogContextRegistry.java
===================================================================
--- projects/logging-service-metadata/trunk/src/main/java/org/jboss/logging/metadata/LogContextRegistry.java	                        (rev 0)
+++ projects/logging-service-metadata/trunk/src/main/java/org/jboss/logging/metadata/LogContextRegistry.java	2009-12-01 01:02:25 UTC (rev 97193)
@@ -0,0 +1,83 @@
+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2009, Red Hat Middleware LLC, and individual contributors
+ * as indicated by the @author tags. See the copyright.txt file in the
+ * distribution for a full listing of individual contributors.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+
+package org.jboss.logging.metadata;
+
+import org.jboss.util.collection.ConcurrentReferenceHashMap;
+import org.jboss.logmanager.LogContext;
+import static org.jboss.util.collection.ConcurrentReferenceHashMap.ReferenceType.*;
+import java.util.concurrent.ConcurrentMap;
+
+/**
+ * A named registry for log contexts.  It retains only weak references to the log context instance.
+ */
+public final class LogContextRegistry {
+
+    private static final LogContextRegistry INSTANCE = new LogContextRegistry();
+
+    private final ConcurrentMap<String, LogContext> map = new ConcurrentReferenceHashMap<String, LogContext>(STRONG, WEAK);
+
+    private LogContextRegistry() {
+        map.put("system", LogContext.getSystemLogContext());
+    }
+
+    /**
+     * Get the named log context.
+     *
+     * @param name the context name
+     * @return the context
+     * @throws IllegalArgumentException if no such log context could be found
+     */
+    public LogContext get(String name) throws IllegalArgumentException {
+        final LogContext context = map.get(name);
+        if (context == null) {
+            throw new IllegalArgumentException("No such log context '" + name + "'");
+        }
+        return context;
+    }
+
+    /**
+     * Get the named log context, creating it if it does not exist.
+     *
+     * @param name the context name
+     * @return the context
+     */
+    public LogContext getOrCreate(String name) {
+        final LogContext context = map.get(name);
+        if (context == null) {
+            final LogContext created = LogContext.create();
+            final LogContext appearing = map.putIfAbsent(name, created);
+            return appearing == null ? created : appearing;
+        } else {
+            return context;
+        }
+    }
+
+    /**
+     * Get the single instance.
+     *
+     * @return the single instance
+     */
+    public static LogContextRegistry getInstance() {
+        return INSTANCE;
+    }
+}