Mercurial > hg > graal-compiler
view graal/com.oracle.truffle.dsl.processor/src/com/oracle/truffle/dsl/processor/util/Filterator.java @ 15128:d0e2d565176f
BaselineCompiler: copy frame state builder at loop headers.
author | Josef Eisl <josef.eisl@jku.at> |
---|---|
date | Tue, 15 Apr 2014 20:35:52 +0200 |
parents | 93068303f856 |
children |
line wrap: on
line source
/* * Copyright (c) 2012, 2012, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.oracle.truffle.dsl.processor.util; import java.util.*; public class Filterator<T> implements Iterator<T> { private final Predicate<T> includePredicate; private final Iterator<T> elements; private boolean hasCached; private T cached; public Filterator(Iterator<T> elements, Predicate<T> includePredicate) { this.elements = elements; this.includePredicate = includePredicate; } public boolean hasNext() { if (hasCached) { return true; } nextValue(); return hasCached; } private void nextValue() { while (!hasCached && elements.hasNext()) { T element = elements.next(); if (includePredicate.evaluate(element)) { cached = element; hasCached = true; } } } public T next() { T foundCached = getCached(); if (foundCached != null) { return foundCached; } else { nextValue(); if (!hasCached) { throw new NoSuchElementException(); } return getCached(); } } private T getCached() { if (hasCached) { hasCached = false; T value = cached; cached = null; return value; } return null; } @Override public void remove() { elements.remove(); } }