CachedResultSetBuilder replaces CachedResultSets (#7325)

Author: labkey-adam

api/src/org/labkey/api/data/BaseSelector.java

@@ -50,8 +50,6 @@
  * A partial, base implementation of {@link org.labkey.api.data.Selector}. This class manipulates result sets but doesn't
  * generate them. Subclasses include ExecutingSelector (which executes SQL to generate a result set) and ResultSetSelector,
  * which takes an externally generated ResultSet (e.g., from JDBC metadata calls) and allows Selector operations on it.
- * User: adam
- * Date: 12/11/12
  */
 
 public abstract class BaseSelector<SELECTOR extends BaseSelector<?>> extends JdbcCommand<SELECTOR> implements Selector

api/src/org/labkey/api/data/CachedResultSetBuilder.java

@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2013-2018 LabKey Corporation
+ *
+ * Licensed 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.
+ */
+package org.labkey.api.data;
+
+import org.labkey.api.collections.ResultSetRowMapFactory;
+import org.labkey.api.collections.RowMap;
+
+import java.sql.ResultSet;
+import java.sql.ResultSetMetaData;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Builder for CachedResultSets, given a {@code ResultSet} or a {@code List<Map<String, Object>>}
+ */
+public abstract class CachedResultSetBuilder<C extends CachedResultSetBuilder<C>>
+{
+    protected boolean _requireClose = true;
+    protected StackTraceElement[] _stackTrace = null;
+
+    public static FromResultSet create(ResultSet rs)
+    {
+        return new FromResultSet(rs);
+    }
+
+    public static FromListOfMaps create(List<Map<String, Object>> maps)
+    {
+        return create(maps, maps.get(0).keySet());
+    }
+
+    /**
+     * Create CachedResultSetBuilder from a list of maps and collection of column names. For the most flexibility, the
+     * maps may need to be case-insensitive. How do you tell? If the maps have data and the keys match the columnNames,
+     * but the ResultSet rowMap values are all null.
+     * @param maps List of row data, possibly case-insensitive maps
+     * @param columnNames Collection of column names
+     *
+     * TODO: A case-insensitive option for the builder, but there may be performance impact for very large result sets
+     * if the implementation were simply to wrap each incoming map with CaseInsensitiveHashMap. For now, onus is on the
+     * caller to provide case insensitive maps when necessary.
+     */
+    public static FromListOfMaps create(List<Map<String, Object>> maps, Collection<String> columnNames)
+    {
+        return new FromListOfMaps(maps, columnNames);
+    }
+
+    public abstract C getThis();
+
+    public C setRequireClose(boolean requireClose)
+    {
+        _requireClose = requireClose;
+        return getThis();
+    }
+
+    public C setStackTrace(StackTraceElement[] stackTrace)
+    {
+        _stackTrace = stackTrace;
+        return getThis();
+    }
+
+    public final static class FromResultSet extends CachedResultSetBuilder<FromResultSet>
+    {
+        private final ResultSet _rs;
+
+        private int _maxRows = Table.ALL_ROWS;
+        private QueryLogging _queryLogging = QueryLogging.emptyQueryLogging();
+
+        private FromResultSet(ResultSet rs)
+        {
+            _rs = rs;
+        }
+
+        @Override
+        public FromResultSet getThis()
+        {
+            return this;
+        }
+
+        public FromResultSet setMaxRows(int maxRows)
+        {
+            _maxRows = maxRows;
+            return this;
+        }
+
+        public FromResultSet setQueryLogging(QueryLogging queryLogging)
+        {
+            _queryLogging = queryLogging;
+            return this;
+        }
+
+        public CachedResultSet build() throws SQLException
+        {
+            try (ResultSet rs = new LoggingResultSetWrapper(_rs, _queryLogging))         // TODO: avoid if we're passed a read-only and empty one??
+            {
+                // Snowflake auto-closes metadata after reading the last row, so cache that metadata first
+                ResultSetMetaData md = new CachedResultSetMetaData(rs.getMetaData());
+
+                ArrayList<RowMap<Object>> list = new ArrayList<>();
+
+                if (_maxRows == Table.ALL_ROWS)
+                    _maxRows = Integer.MAX_VALUE;
+
+                ResultSetRowMapFactory factory = ResultSetRowMapFactory.create(rs);
+
+                // Note: we check in this order to avoid consuming the "extra" row used to detect complete vs. not
+                while (list.size() < _maxRows && rs.next())
+                    list.add(factory.getRowMap(rs));
+
+                // If we have another row, then we're not complete
+                boolean isComplete = !rs.next();
+
+                return new CachedResultSet(md, list, isComplete, _requireClose, _stackTrace);
+            }
+        }
+    }
+
+    public final static class FromListOfMaps extends CachedResultSetBuilder<FromListOfMaps>
+    {
+        private final List<Map<String, Object>> _maps;
+        private final Collection<String> _columnNames;
+
+        private ResultSetMetaData _md = null;
+        private boolean _isComplete = true;
+
+        private FromListOfMaps(List<Map<String, Object>> maps, Collection<String> columnNames)
+        {
+            _maps = maps;
+            _columnNames = columnNames;
+        }
+
+        @Override
+        public FromListOfMaps getThis()
+        {
+            return this;
+        }
+
+        public FromListOfMaps setMetaData(ResultSetMetaData md)
+        {
+            _md = md;
+            return this;
+        }
+
+        public FromListOfMaps setComplete(boolean complete)
+        {
+            _isComplete = complete;
+            return this;
+        }
+
+        public CachedResultSet build()
+        {
+            if (_md == null)
+                _md = createMetaData(_columnNames);
+
+            return new CachedResultSet(_md, convertToRowMaps(_md, _maps), _isComplete, _requireClose, _stackTrace);
+        }
+    }
+
+    private static ResultSetMetaData createMetaData(Collection<String> columnNames)
+    {
+        ResultSetMetaDataImpl md = new ResultSetMetaDataImpl(columnNames.size());
+        for (String columnName : columnNames)
+        {
+            ResultSetMetaDataImpl.ColumnMetaData col = new ResultSetMetaDataImpl.ColumnMetaData();
+            col.columnName = columnName;
+            col.columnLabel = columnName;
+            md.addColumn(col);
+        }
+
+        return md;
+    }
+
+    private static ArrayList<RowMap<Object>> convertToRowMaps(ResultSetMetaData md, List<Map<String, Object>> maps)
+    {
+        ArrayList<RowMap<Object>> list = new ArrayList<>();
+
+        ResultSetRowMapFactory factory;
+        try
+        {
+            factory = ResultSetRowMapFactory.create(md);
+        }
+        catch (SQLException e)
+        {
+            throw new RuntimeSQLException(e);
+        }
+
+        for (Map<String, Object> map : maps)
+        {
+            list.add(factory.getRowMap(map));
+        }
+
+        return list;
+    }
+}

api/src/org/labkey/api/data/CachedResultSets.java

@@ -1878,7 +1878,7 @@ private static void detectUnexpectedConnections(Connection conn, LabKeyDataSourc
             stmt.setString(1, databaseName);
             stmt.setString(2, applicationName);
 
-            try (CachedResultSet rs = CachedResultSets.create(stmt.executeQuery(), true, true, 1000))
+            try (CachedResultSet rs = CachedResultSetBuilder.create(stmt.executeQuery()).setMaxRows(1000).build())
             {
                 count = rs.getSize();
                 if (count != 0)

api/src/org/labkey/api/data/DbScope.java

@@ -103,7 +103,7 @@ protected TableResultSet wrapResultSet(ResultSet rs, Connection conn, boolean ca
     {
         if (cache)
         {
-            return CachedResultSets.create(rs, true, requireClose, Table.ALL_ROWS);
+            return CachedResultSetBuilder.create(rs).setRequireClose(requireClose).build();
         }
         else
         {

api/src/org/labkey/api/data/ResultSetSelector.java

@@ -79,7 +79,7 @@ private <K> void test(DbScope scope, ResultSet rs, Class<K> clazz) throws SQLExc
                 assertEquals("Non-scrollable ResultSet can't be used with ScrollToTop", e.getMessage());
             }
 
-            rs = CachedResultSets.create(rs, true, true, Table.ALL_ROWS, null, QueryLogging.emptyQueryLogging());
+            rs = CachedResultSetBuilder.create(rs).build();
         }
 
         ResultSetSelector selector = new ResultSetSelector(scope, rs);

api/src/org/labkey/api/data/ResultSetSelectorTestCase.java

@@ -211,7 +211,7 @@ protected TableResultSet wrapResultSet(ResultSet rs, Connection conn, boolean ca
         if (cache)
         {
             // Cache ResultSet and meta data
-            return CachedResultSets.create(rs, true, requireClose, _maxRows, _loggingStacktrace, getQueryLogging());
+            return CachedResultSetBuilder.create(rs).setRequireClose(requireClose).setMaxRows(_maxRows).setStackTrace(_loggingStacktrace).setQueryLogging(getQueryLogging()).build();
         }
         else
         {