Exactly index sortkey with Lucene

Store sortkey as a long and implement the before and after operators
as numeric range queries.  This is a short-term hack until we have a
better idea of how to handle pagination without relying on a made up
string value stored on the change object.

Change-Id: Ibf7a8be281da8cd9e7ccc08bba600bbc2e0e962c

gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java

@@ -44,6 +44,7 @@ import com.google.gerrit.server.query.QueryParseException;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.query.change.ChangeDataSource;
 import com.google.gerrit.server.query.change.IndexRewriteImpl;
+import com.google.gerrit.server.query.change.SortKeyPredicate;
 import com.google.gwtorm.server.OrmException;
 import com.google.gwtorm.server.ResultSet;
 
@@ -52,6 +53,7 @@ import org.apache.lucene.document.Document;
 import org.apache.lucene.document.Field;
 import org.apache.lucene.document.Field.Store;
 import org.apache.lucene.document.IntField;
+import org.apache.lucene.document.LongField;
 import org.apache.lucene.document.StringField;
 import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.index.IndexWriterConfig;
@@ -261,6 +263,8 @@ public class LuceneChangeIndex implements ChangeIndex, LifecycleListener {
       return exactQuery(p);
     } else if (p.getType() == FieldType.PREFIX) {
       return prefixQuery(p);
+    } else if (p instanceof SortKeyPredicate) {
+      return sortKeyQuery((SortKeyPredicate) p);
     } else {
       throw badFieldType(p.getType());
     }
@@ -285,6 +289,14 @@ public class LuceneChangeIndex implements ChangeIndex, LifecycleListener {
     return new TermQuery(intTerm(p.getOperator(), value));
   }
 
+  private static Query sortKeyQuery(SortKeyPredicate p) {
+    return NumericRangeQuery.newLongRange(
+        p.getField().getName(),
+        p.getMinValue(),
+        p.getMaxValue(),
+        true, true);
+  }
+
   private static Query timestampQuery(IndexPredicate<ChangeData> p)
       throws QueryParseException {
     if (p instanceof TimestampRangePredicate) {
@@ -442,6 +454,10 @@ public class LuceneChangeIndex implements ChangeIndex, LifecycleListener {
       for (Object value : values) {
         doc.add(new IntField(name, (Integer) value, store));
       }
+    } else if (f.getType() == FieldType.LONG) {
+      for (Object value : values) {
+        doc.add(new LongField(name, (Long) value, store));
+      }
     } else if (f.getType() == FieldType.TIMESTAMP) {
       for (Object v : values) {
         doc.add(new IntField(name, toIndexTime((Timestamp) v), store));

gerrit-server/src/main/java/com/google/gerrit/server/ChangeUtil.java

@@ -450,16 +450,15 @@ public class ChangeUtil {
     return r.toString();
   }
 
-  public static Timestamp timeFromSortKey(String sortKey) {
+  public static long parseSortKey(String sortKey) {
     if ("z".equals(sortKey)) {
-      return new Timestamp(Long.MAX_VALUE);
+      return Long.MAX_VALUE;
     }
     String ts = sortKey.substring(0, 8);
     int i = 0;
     while (i < 8 && ts.charAt(i) == '0')
       i++;
-    long v = Long.parseLong(ts.substring(i), 16) * 60;
-    return new Timestamp((v + SORT_KEY_EPOCH) * 1000);
+    return Long.parseLong(ts.substring(i), 16);
   }
 
   public static void computeSortKey(final Change c) {

gerrit-server/src/main/java/com/google/gerrit/server/index/ChangeField.java

@@ -19,6 +19,7 @@ import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.google.gerrit.reviewdb.client.PatchSetApproval;
 import com.google.gerrit.reviewdb.client.PatchSet;
+import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.query.change.ChangeQueryBuilder;
 import com.google.gerrit.server.query.change.ChangeStatusPredicate;
@@ -43,7 +44,7 @@ import java.util.Set;
  */
 public class ChangeField {
   /** Increment whenever making schema changes. */
-  public static final int SCHEMA_VERSION = 5;
+  public static final int SCHEMA_VERSION = 6;
 
   /** Legacy change ID. */
   public static final FieldDef<ChangeData, Integer> CHANGE_ID =
@@ -111,6 +112,18 @@ public class ChangeField {
         }
       };
 
+  /** Sort key field, duplicates {@link #UPDATED}. */
+  @Deprecated
+  public static final FieldDef<ChangeData, Long> SORTKEY =
+      new FieldDef.Single<ChangeData, Long>(
+          "sortkey", FieldType.LONG, true) {
+        @Override
+        public Long get(ChangeData input, FillArgs args)
+            throws OrmException {
+          return ChangeUtil.parseSortKey(input.change(args.db).getSortKey());
+        }
+      };
+
   /** List of filenames modified in the current patch set. */
   public static final FieldDef<ChangeData, Iterable<String>> FILE =
       new FieldDef.Repeatable<ChangeData, String>(

gerrit-server/src/main/java/com/google/gerrit/server/index/FieldType.java

@@ -23,6 +23,10 @@ public class FieldType<T> {
   public static final FieldType<Integer> INTEGER =
       new FieldType<Integer>("INTEGER");
 
+  /** A single integer-valued field. */
+  public static final FieldType<Long> LONG =
+      new FieldType<Long>("LONG");
+
   /** A single date/time-valued field. */
   public static final FieldType<Timestamp> TIMESTAMP =
       new FieldType<Timestamp>("TIMESTAMP");

gerrit-server/src/main/java/com/google/gerrit/server/query/change/SortKeyPredicate.java

@@ -18,18 +18,15 @@ import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.index.ChangeField;
-import com.google.gerrit.server.index.TimestampRangePredicate;
+import com.google.gerrit.server.index.IndexPredicate;
 import com.google.gwtorm.server.OrmException;
 import com.google.inject.Provider;
 
-import java.sql.Timestamp;
-
-public abstract class SortKeyPredicate extends
-    TimestampRangePredicate<ChangeData> {
+public abstract class SortKeyPredicate extends IndexPredicate<ChangeData> {
   protected final Provider<ReviewDb> dbProvider;
 
   SortKeyPredicate(Provider<ReviewDb> dbProvider, String name, String value) {
-    super(ChangeField.UPDATED, name, value);
+    super(ChangeField.SORTKEY, name, value);
     this.dbProvider = dbProvider;
   }
 
@@ -38,19 +35,22 @@ public abstract class SortKeyPredicate extends
     return 1;
   }
 
+  public abstract long getMinValue();
+  public abstract long getMaxValue();
+
   public static class Before extends SortKeyPredicate {
     Before(Provider<ReviewDb> dbProvider, String value) {
       super(dbProvider, "sortkey_before", value);
     }
 
     @Override
-    public Timestamp getMinTimestamp() {
-      return new Timestamp(0);
+    public long getMinValue() {
+      return 0;
     }
 
     @Override
-    public Timestamp getMaxTimestamp() {
-      return ChangeUtil.timeFromSortKey(getValue());
+    public long getMaxValue() {
+      return ChangeUtil.parseSortKey(getValue());
     }
 
     @Override
@@ -66,13 +66,13 @@ public abstract class SortKeyPredicate extends
     }
 
     @Override
-    public Timestamp getMinTimestamp() {
-      return ChangeUtil.timeFromSortKey(getValue());
+    public long getMinValue() {
+      return ChangeUtil.parseSortKey(getValue());
     }
 
     @Override
-    public Timestamp getMaxTimestamp() {
-      return new Timestamp(Long.MAX_VALUE);
+    public long getMaxValue() {
+      return Long.MAX_VALUE;
     }
 
     @Override