1 files changed, 177 insertions, 0 deletions
diff --git a/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/ASTComparisonNode.java b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/ASTComparisonNode.java
new file mode 100644
index 00000000..721aa23d
--- /dev/null
+++ b/velocity-engine-core/src/main/java/org/apache/velocity/runtime/parser/node/ASTComparisonNode.java
@@ -0,0 +1,177 @@
+package org.apache.velocity.runtime.parser.node;
+
+/*
+ * 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.
+ */
+
+import org.apache.velocity.context.InternalContextAdapter;
+import org.apache.velocity.exception.MethodInvocationException;
+import org.apache.velocity.exception.VelocityException;
+import org.apache.velocity.runtime.RuntimeConstants;
+import org.apache.velocity.runtime.parser.Parser;
+import org.apache.velocity.util.DuckType;
+import org.apache.velocity.util.StringUtils;
+
+/**
+ * Numeric comparison support<br><br>
+ *
+ * @author <a href="mailto:wglass@forio.com">Will Glass-Husain</a>
+ * @author <a href="mailto:pero@antaramusic.de">Peter Romianowski</a>
+ * @author Nathan Bubna
+ */
+public abstract class ASTComparisonNode extends ASTBinaryOperator
+{
+    /**
+     * @param id
+     */
+    public ASTComparisonNode(int id)
+    {
+        super(id);
+    }
+
+    /**
+     * @param p
+     * @param id
+     */
+    public ASTComparisonNode(Parser p, int id)
+    {
+        super(p, id);
+    }
+
+
+    /**
+     * @see org.apache.velocity.runtime.parser.node.SimpleNode#jjtAccept(org.apache.velocity.runtime.parser.node.ParserVisitor, java.lang.Object)
+     */
+    @Override
+    public Object jjtAccept(ParserVisitor visitor, Object data)
+    {
+        return visitor.visit(this, data);
+    }
+
+    /**
+     * @see org.apache.velocity.runtime.parser.node.SimpleNode#evaluate(org.apache.velocity.context.InternalContextAdapter)
+     */
+    @Override
+    public boolean evaluate(InternalContextAdapter context) throws MethodInvocationException
+    {
+        Object left = jjtGetChild(0).value(context);
+        Object right = jjtGetChild(1).value(context);
+
+        if (left == null || right == null)
+        {
+            return compareNull(left, right);
+        }
+        Boolean result = compareNumbers(left, right);
+        if (result == null)
+        {
+            result = compareNonNumber(left, right);
+        }
+        return result;
+    }
+
+    /**
+     * Always false by default, != and == subclasses must override this.
+     * @param left
+     * @param right
+     * @return comparison result
+     */
+    public boolean compareNull(Object left, Object right)
+    {
+        // if either side is null, log and bail
+        String msg = (left == null ? "Left" : "Right")
+                       + " side ("
+                       + jjtGetChild( (left == null? 0 : 1) ).literal()
+                       + ") of comparison operation has null value at "
+                       + StringUtils.formatFileString(this);
+        if (rsvc.getBoolean(RuntimeConstants.RUNTIME_REFERENCES_STRICT, false))
+        {
+            throw new VelocityException(msg, null, rsvc.getLogContext().getStackTrace());
+        }
+        log.error(msg);
+        return false;
+    }
+
+    /**
+     * compare numbers
+     * @param left
+     * @param right
+     * @return comparison result
+     */
+    public Boolean compareNumbers(Object left, Object right)
+    {
+        try
+        {
+            left = DuckType.asNumber(left);
+        }
+        catch (NumberFormatException nfe) {}
+        try
+        {
+            right = DuckType.asNumber(right);
+        }
+        catch (NumberFormatException nfe) {}
+
+        // only compare Numbers
+        if (left instanceof Number && right instanceof Number)
+        {
+            return numberTest(MathUtils.compare((Number)left, (Number)right));
+        }
+        return null;
+    }
+
+    /**
+     * get the string representing the mathematical operator
+     * @return operator string
+     */
+    @Override
+    public abstract String getLiteralOperator();
+
+    /**
+     * performs the actual comparison
+     * @param compareResult
+     * @return comparison result
+     */
+    public abstract boolean numberTest(int compareResult);
+
+    public boolean compareNonNumber(Object left, Object right)
+    {
+        // by default, log and bail
+        String msg = (right instanceof Number ? "Left" : "Right")
+                       + " side of comparison operation is not a number at "
+                       + StringUtils.formatFileString(this);
+        if (rsvc.getBoolean(RuntimeConstants.RUNTIME_REFERENCES_STRICT, false))
+        {
+            throw new VelocityException(msg, null, rsvc.getLogContext().getStackTrace());
+        }
+        log.error(msg);
+        return false;
+    }
+
+    private String getLiteral(boolean left)
+    {
+        return jjtGetChild(left ? 0 : 1).literal();
+    }
+
+    /**
+     * @see org.apache.velocity.runtime.parser.node.SimpleNode#value(org.apache.velocity.context.InternalContextAdapter)
+     */
+    @Override
+    public Object value(InternalContextAdapter context) throws MethodInvocationException
+    {
+        return evaluate(context);
+    }
+}