1 files changed, 120 insertions, 0 deletions
diff --git a/qpid/java/broker/src/main/java/org/apache/qpid/server/filter/LogicExpression.java b/qpid/java/broker/src/main/java/org/apache/qpid/server/filter/LogicExpression.java
new file mode 100644
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+++ b/qpid/java/broker/src/main/java/org/apache/qpid/server/filter/LogicExpression.java
@@ -0,0 +1,120 @@
+/**
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.qpid.server.filter;
+//
+// Based on like named file from r450141 of the Apache ActiveMQ project <http://www.activemq.org/site/home.html>
+//
+
+import org.apache.qpid.server.queue.Filterable;
+
+/**
+ * A filter performing a comparison of two objects
+ */
+public abstract class LogicExpression extends BinaryExpression implements BooleanExpression
+{
+
+    public static BooleanExpression createOR(BooleanExpression lvalue, BooleanExpression rvalue)
+    {
+        return new OrExpression(lvalue, rvalue);
+    }
+
+    public static BooleanExpression createAND(BooleanExpression lvalue, BooleanExpression rvalue)
+    {
+        return new AndExpression(lvalue, rvalue);
+    }
+
+    /**
+     * @param left
+     * @param right
+     */
+    public LogicExpression(BooleanExpression left, BooleanExpression right)
+    {
+        super(left, right);
+    }
+
+    public abstract Object evaluate(Filterable message);
+
+    public boolean matches(Filterable message)
+    {
+        Object object = evaluate(message);
+
+        return (object != null) && (object == Boolean.TRUE);
+    }
+
+    private static class OrExpression extends LogicExpression
+    {
+        public OrExpression(final BooleanExpression lvalue, final BooleanExpression rvalue)
+        {
+            super(lvalue, rvalue);
+        }
+
+        public Object evaluate(Filterable message)
+        {
+
+            Boolean lv = (Boolean) left.evaluate(message);
+            // Can we do an OR shortcut??
+            if ((lv != null) && lv.booleanValue())
+            {
+                return Boolean.TRUE;
+            }
+
+            Boolean rv = (Boolean) right.evaluate(message);
+
+            return (rv == null) ? null : rv;
+        }
+
+        public String getExpressionSymbol()
+        {
+            return "OR";
+        }
+    }
+
+    private static class AndExpression extends LogicExpression
+    {
+        public AndExpression(final BooleanExpression lvalue, final BooleanExpression rvalue)
+        {
+            super(lvalue, rvalue);
+        }
+
+        public Object evaluate(Filterable message)
+        {
+
+            Boolean lv = (Boolean) left.evaluate(message);
+
+            // Can we do an AND shortcut??
+            if (lv == null)
+            {
+                return null;
+            }
+
+            if (!lv.booleanValue())
+            {
+                return Boolean.FALSE;
+            }
+
+            Boolean rv = (Boolean) right.evaluate(message);
+
+            return (rv == null) ? null : rv;
+        }
+
+        public String getExpressionSymbol()
+        {
+            return "AND";
+        }
+    }
+}