1 files changed, 116 insertions, 0 deletions
diff --git a/searchlib/src/main/java/com/yahoo/searchlib/expression/DocumentFieldNode.java b/searchlib/src/main/java/com/yahoo/searchlib/expression/DocumentFieldNode.java
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+++ b/searchlib/src/main/java/com/yahoo/searchlib/expression/DocumentFieldNode.java
@@ -0,0 +1,116 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.searchlib.expression;
+
+import com.yahoo.vespa.objects.Deserializer;
+import com.yahoo.vespa.objects.ObjectVisitor;
+import com.yahoo.vespa.objects.Serializer;
+
+/**
+ * The node is a request to retrieve the content of a document field.
+ *
+ * @author <a href="mailto:balder@yahoo-inc.com">Henning Baldersheim</a>
+ * @author <a href="mailto:simon@yahoo-inc.com">Simon Thoresen</a>
+ */
+public class DocumentFieldNode extends DocumentAccessorNode {
+
+    public static final int classId = registerClass(0x4000 + 56, DocumentFieldNode.class);
+    private String fieldName;
+    private ResultNode result;
+
+    /**
+     * Constructs an empty result node. <b>NOTE:</b> This instance is broken until non-optional member data is set.
+     */
+    public DocumentFieldNode() {
+        super();
+    }
+
+    /**
+     * Constructs an instance of this class with given field name.
+     *
+     * @param fieldName The field whose value to retrieve.
+     */
+    public DocumentFieldNode(String fieldName) {
+        super();
+        setDocumentFieldName(fieldName);
+    }
+
+    /**
+     * Returns the name of the field whose value to retrieve.
+     *
+     * @return The field name.
+     */
+    public String getDocumentFieldName() {
+        return fieldName;
+    }
+
+    /**
+     * Sets the name of the field whose value to retrieve.
+     *
+     * @param fieldName The field name to set.
+     * @return This, to allow chaining.
+     */
+    public DocumentFieldNode setDocumentFieldName(String fieldName) {
+        if (fieldName == null) {
+            throw new IllegalArgumentException("Field name can not be null.");
+        }
+        this.fieldName = fieldName;
+        return this;
+    }
+
+    @Override
+    public ResultNode getResult() {
+        return result;
+    }
+
+    @Override
+    protected int onGetClassId() {
+        return classId;
+    }
+
+    @Override
+    protected void onSerialize(Serializer buf) {
+        super.onSerialize(buf);
+        putUtf8(buf, fieldName);
+        serializeOptional(buf, result);
+    }
+
+    @Override
+    protected void onDeserialize(Deserializer buf) {
+        super.onDeserialize(buf);
+        fieldName = getUtf8(buf);
+        result = (ResultNode)deserializeOptional(buf);
+    }
+
+    @Override
+    public int hashCode() {
+        return super.hashCode() + fieldName.hashCode();
+    }
+
+    @Override
+    protected boolean equalsExpression(ExpressionNode obj) {
+        DocumentFieldNode rhs = (DocumentFieldNode)obj;
+        if (!fieldName.equals(rhs.fieldName)) {
+            return false;
+        }
+        if (!equals(result, rhs.result)) {
+            return false;
+        }
+        return true;
+    }
+
+    @Override
+    public DocumentFieldNode clone() {
+        DocumentFieldNode obj = (DocumentFieldNode)super.clone();
+        if (result != null) {
+            obj.result = (ResultNode)result.clone();
+        }
+        return obj;
+    }
+
+    @Override
+    public void visitMembers(ObjectVisitor visitor) {
+        super.visitMembers(visitor);
+        visitor.visit("fieldName", fieldName);
+        visitor.visit("result", result);
+    }
+}