| // Copyright 2010 The Apache Software Foundation |
| // |
| // 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.apache.tapestry5.func; |
| |
| class LazyZip<A, B> implements LazyFunction<Tuple<A, B>> |
| { |
| private final Flow<A> aFlow; |
| |
| private final Flow<B> bFlow; |
| |
| public LazyZip(Flow<A> aFlow, Flow<B> bFlow) |
| { |
| this.aFlow = aFlow; |
| this.bFlow = bFlow; |
| } |
| |
| @Override |
| public LazyContinuation<Tuple<A, B>> next() |
| { |
| if (aFlow.isEmpty() || bFlow.isEmpty()) |
| return null; |
| |
| LazyZipValue<A, B> nextValue = new LazyZipValue<A, B>(aFlow, bFlow); |
| |
| return new LazyContinuation<Tuple<A, B>>(nextValue, new LazyZip<A, B>(aFlow.rest(), bFlow.rest())); |
| } |
| } |