--- /dev/null 2017-01-22 10:16:57.869617664 -0800 +++ new/src/jdk.internal.vm.ci/share/classes/jdk.vm.ci.meta/src/jdk/vm/ci/meta/AbstractProfiledItem.java 2017-02-15 16:56:03.943958453 -0800 @@ -0,0 +1,95 @@ +/* + * Copyright (c) 2013, 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 jdk.vm.ci.meta; + +/** + * A profiled type that has a probability. Profiled types are naturally sorted in descending order + * of their probabilities. + */ +public abstract class AbstractProfiledItem implements Comparable> { + + protected final T item; + protected final double probability; + + public AbstractProfiledItem(T item, double probability) { + assert item != null; + assert probability >= 0.0D && probability <= 1.0D; + this.item = item; + this.probability = probability; + } + + protected T getItem() { + return item; + } + + /** + * Returns the estimated probability of {@link #getItem()}. + * + * @return double value ≥ 0.0 and ≤ 1.0 + */ + public double getProbability() { + return probability; + } + + /** + * Returns -1 if the {@linkplain #getProbability() probability} of this item is greater than + * {@code o}'s probability, 0 if there are equal otherwise 1. + */ + @Override + public int compareTo(AbstractProfiledItem o) { + // Need to swap the order of operands so that higher probabilities are sorted first + return Double.compare(o.getProbability(), getProbability()); + } + + @Override + public int hashCode() { + final int prime = 31; + int result = 1; + long temp; + temp = Double.doubleToLongBits(probability); + result = prime * result + (int) (temp ^ (temp >>> 32)); + result = prime * result + item.hashCode(); + return result; + } + + @Override + public boolean equals(Object obj) { + if (this == obj) { + return true; + } + if (obj == null) { + return false; + } + if (getClass() != obj.getClass()) { + return false; + } + AbstractProfiledItem other = (AbstractProfiledItem) obj; + if (Double.doubleToLongBits(probability) != Double.doubleToLongBits(other.probability)) { + return false; + } + return item.equals(other.item); + } + + @Override + public abstract String toString(); +}