missing interface

h2/src/main/org/h2/index/IndexLookupBatch.java

+/*
+ * Copyright 2004-2014 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.index;
+
+import java.util.List;
+import java.util.concurrent.Future;
+import org.h2.result.SearchRow;
+
+/**
+ * Support for asynchronous batched lookups in indexes. The flow is the following:
+ * H2 engine will be calling {@link #addSearchRows(SearchRow, SearchRow)} until
+ * method {@link #isBatchFull()}} will return {@code true} or there are no more
+ * search rows to add. Then method {@link #find()} will be called to execute batched lookup.
+ * Note that a single instance of {@link IndexLookupBatch} can be reused for multiple 
+ * sequential batched lookups.
+ * 
+ * @see Index#createLookupBatch(TableFilter)
+ * @author Sergi Vladykin
+ */
+public interface IndexLookupBatch {
+    /**
+     * Add search row pair to the batch.
+     * 
+     * @param first the first row, or null for no limit
+     * @param last the last row, or null for no limit
+     * @see Index#find(TableFilter, SearchRow, SearchRow)
+     */
+    void addSearchRows(SearchRow first, SearchRow last);
+
+    /**
+     * Check if this batch is full.
+     * 
+     * @return {@code true} If batch is full, will not accept any 
+     *          more rows and {@link #find()} can be executed.
+     */
+    boolean isBatchFull();
+    
+    /**
+     * Execute batched lookup and return future cursor for each provided
+     * search row pair. Note that this method must return exactly the same number
+     * of future cursors in result list as number of {@link #addSearchRows(SearchRow, SearchRow)} 
+     * calls has been done before {@link #find()} call exactly in the same order.  
+     * 
+     * @return List of future cursors for collected search rows.
+     */
+    List<Future<Cursor>> find();
+}