/*
* Licensed to Crate under one or more contributor license agreements.
* See the NOTICE file distributed with this work for additional
* information regarding copyright ownership. Crate licenses this file
* to you 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.
*
* However, if you have executed another commercial license agreement
* with Crate these terms will supersede the license and you may use the
* software solely pursuant to the terms of the relevant commercial
* agreement.
*/
package io.crate.metadata;
import io.crate.analyze.symbol.DynamicReference;
import io.crate.analyze.symbol.Function;
import io.crate.analyze.symbol.Symbol;
import io.crate.analyze.symbol.SymbolVisitor;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
public class ReplacingSymbolVisitor<C> extends SymbolVisitor<C, Symbol> {
private final ReplaceMode mode;
public ReplacingSymbolVisitor(ReplaceMode mode) {
this.mode = mode;
}
private Symbol copyFunction(Function function, C context) {
List<Symbol> newArgs = process(function.arguments(), context);
if (newArgs != function.arguments()) {
function = new Function(function.info(), newArgs);
}
return function;
}
@Override
public Symbol visitFunction(Function symbol, C context) {
if (mode == ReplaceMode.MUTATE) {
processInplace(symbol.arguments(), context);
return symbol;
}
return copyFunction(symbol, context);
}
public List<Symbol> process(Collection<Symbol> symbols, C context) {
ArrayList<Symbol> copy = new ArrayList<>(symbols.size());
for (Symbol symbol : symbols) {
copy.add(process(symbol, context));
}
return copy;
}
public void processInplace(List<Symbol> symbols, C context) {
for (int i = 0; i < symbols.size(); i++) {
symbols.set(i, process(symbols.get(i), context));
}
}
@Override
protected Symbol visitSymbol(Symbol symbol, C context) {
return symbol;
}
@Override
public Symbol visitDynamicReference(DynamicReference symbol, C context) {
return visitReference(symbol, context);
}
}