/*
 * 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 com.facebook.presto.sql.planner.iterative.rule;

import com.facebook.presto.Session;
import com.facebook.presto.sql.planner.PlanNodeIdAllocator;
import com.facebook.presto.sql.planner.Symbol;
import com.facebook.presto.sql.planner.SymbolAllocator;
import com.facebook.presto.sql.planner.iterative.Lookup;
import com.facebook.presto.sql.planner.iterative.Pattern;
import com.facebook.presto.sql.planner.iterative.Rule;
import com.facebook.presto.sql.planner.plan.PlanNode;
import com.facebook.presto.sql.planner.plan.ProjectNode;
import com.facebook.presto.sql.planner.plan.TableScanNode;

import java.util.List;
import java.util.Optional;
import java.util.Set;
import java.util.function.Function;
import java.util.stream.Collectors;

import static com.facebook.presto.sql.planner.iterative.rule.Util.pruneInputs;
import static com.facebook.presto.util.MoreLists.filteredCopy;

public class PruneTableScanColumns
        implements Rule
{
    private static final Pattern PATTERN = Pattern.node(ProjectNode.class);

    @Override
    public Pattern getPattern()
    {
        return PATTERN;
    }

    @Override
    public Optional<PlanNode> apply(PlanNode node, Lookup lookup, PlanNodeIdAllocator idAllocator, SymbolAllocator symbolAllocator, Session session)
    {
        ProjectNode parent = (ProjectNode) node;

        PlanNode source = lookup.resolve(parent.getSource());
        if (!(source instanceof TableScanNode)) {
            return Optional.empty();
        }

        TableScanNode child = (TableScanNode) source;

        Optional<Set<Symbol>> dependencies = pruneInputs(child.getOutputSymbols(), parent.getAssignments().getExpressions());
        if (!dependencies.isPresent()) {
            return Optional.empty();
        }

        List<Symbol> newOutputs = filteredCopy(child.getOutputSymbols(), dependencies.get()::contains);

        return Optional.of(
                new ProjectNode(
                        parent.getId(),
                        new TableScanNode(
                                child.getId(),
                                child.getTable(),
                                newOutputs,
                                newOutputs.stream()
                                        .collect(Collectors.toMap(Function.identity(), e -> child.getAssignments().get(e))),
                                child.getLayout(),
                                child.getCurrentConstraint(),
                                child.getOriginalConstraint()),
                        parent.getAssignments()));
    }
}

@@ -1156,31 +1156,8 @@
 e;%0A%0A
-import java.util.List;%0A
 impo
@@ -1204,80 +1204,8 @@
 Set;
-%0Aimport java.util.function.Function;%0Aimport java.util.stream.Collectors;
 %0A%0Aim
@@ -1343,16 +1343,73 @@
 redCopy;
+%0Aimport static com.google.common.collect.Maps.filterKeys;
 %0A%0Apublic
@@ -2276,113 +2276,8 @@
  %7D%0A%0A
-        List%3CSymbol%3E newOutputs = filteredCopy(child.getOutputSymbols(), dependencies.get()::contains);%0A%0A
     
@@ -2300,16 +2300,16 @@
 nal.of(%0A
+
         
@@ -2549,194 +2549,173 @@
     
-newOutputs,%0A                                newOutputs.stream()%0A                                        .collect(Collectors.toMap(Function.identity(), e -%3E child.getAssignments().get(e))
+filteredCopy(child.getOutputSymbols(), dependencies.get()::contains),%0A                                filterKeys(child.getAssignments(), dependencies.get()::contains
 ),%0A 

Use fiterkeys instead of filtering manually