Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with this * work for additional information regarding copyright ownership. The ASF * 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. * * Copyright 2013 * */ package cosmos.sql.call.impl; import java.util.List; import com.google.common.base.Function; import com.google.common.base.Preconditions; import com.google.common.collect.Iterables; import com.google.common.collect.Lists; import cosmos.sql.call.BaseVisitor; import cosmos.sql.call.CallIfc; import cosmos.sql.call.ChildVisitor; public class Filter extends BaseVisitor<CallIfc<?>> { public Filter() { } @Override public CallIfc<?> addChild(String id, CallIfc<?> child) { Preconditions.checkArgument(child instanceof ChildVisitor); return super.addChild(id, child); } public List<ChildVisitor> getFilters() { return Lists.newArrayList(Iterables.transform(children.values(), new Function<CallIfc<?>, ChildVisitor>() { @Override public ChildVisitor apply(CallIfc<?> child) { return (ChildVisitor) child; } })); } }