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diff --git a/config-model/src/main/java/com/yahoo/searchdefinition/processing/NGramMatch.java b/config-model/src/main/java/com/yahoo/searchdefinition/processing/NGramMatch.java
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+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.searchdefinition.processing;
+
+import com.yahoo.config.application.api.DeployLogger;
+import com.yahoo.searchdefinition.RankProfileRegistry;
+import com.yahoo.document.*;
+import com.yahoo.searchdefinition.Search;
+import com.yahoo.searchdefinition.document.Matching;
+import com.yahoo.searchdefinition.document.SDField;
+import com.yahoo.searchdefinition.document.Stemming;
+import com.yahoo.vespa.indexinglanguage.expressions.*;
+import com.yahoo.vespa.model.container.search.QueryProfiles;
+
+/**
+ * The implementation of "gram" matching - splitting the incoming text and the queries into
+ * n-grams for matching. This will also validate the gram settings.
+ *
+ * @author <a href="mailto:bratseth@yahoo-inc.com">Jon Bratseth</a>
+ */
+public class NGramMatch extends Processor {
+
+    public static final int DEFAULT_GRAM_SIZE = 2;
+
+    public NGramMatch(Search search, DeployLogger deployLogger, RankProfileRegistry rankProfileRegistry, QueryProfiles queryProfiles) {
+        super(search, deployLogger, rankProfileRegistry, queryProfiles);
+    }
+
+    @Override
+    public void process() {
+        for (SDField field : search.allFieldsList()) {
+            if (field.getMatching().getType().equals(Matching.Type.GRAM))
+                implementGramMatch(search, field);
+            else if (field.getMatching().getGramSize()>=0)
+                throw new IllegalArgumentException("gram-size can only be set when the matching mode is 'gram'");
+        }
+    }
+
+    private void implementGramMatch(Search search, SDField field) {
+        if (field.doesAttributing())
+            throw new IllegalArgumentException("gram matching is not supported with attributes, use 'index' not 'attribute' in indexing");
+
+        int n = field.getMatching().getGramSize();
+        if (n<0)
+            n=DEFAULT_GRAM_SIZE; // not set - use default gram size
+        if (n==0)
+            throw new IllegalArgumentException("Illegal gram size in " + field + ": Must be at least 1");
+        field.getNormalizing().inferCodepoint();
+        field.setStemming(Stemming.NONE); // not compatible with stemming and normalizing
+        field.addQueryCommand("ngram " + n);
+        field.setIndexingScript((ScriptExpression)new MyProvider(search, n).convert(field.getIndexingScript()));
+    }
+
+    private static class MyProvider extends TypedTransformProvider {
+
+        final int ngram;
+
+        MyProvider(Search search, int ngram) {
+            super(NGramExpression.class, search);
+            this.ngram = ngram;
+        }
+
+        @Override
+        protected boolean requiresTransform(Expression exp, DataType fieldType) {
+            return exp instanceof OutputExpression;
+        }
+
+        @Override
+        protected Expression newTransform(DataType fieldType) {
+            Expression exp = new NGramExpression(null, ngram);
+            if (fieldType instanceof CollectionDataType) {
+                exp = new ForEachExpression(exp);
+            }
+            return exp;
+        }
+    }
+}