1 /* 2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package org.graalvm.compiler.lir.phases; 24 25 import java.util.ArrayList; 26 import java.util.ListIterator; 27 28 /** 29 * Allows storing of arbitrary data. 30 */ 31 public class GenericContext { 32 33 private ArrayList<Object> context; 34 35 public GenericContext() { 36 context = null; 37 } 38 39 public <T> void contextAdd(T obj) { 40 if (context == null) { 41 context = new ArrayList<>(); 42 } 43 context.add(obj); 44 } 45 46 @SuppressWarnings("unchecked") 47 public <T> T contextLookup(Class<T> clazz) { 48 if (context != null) { 49 for (Object e : context) { 50 if (clazz.isInstance(e)) { 51 return (T) e; 52 } 53 } 54 } 55 return null; 56 } 57 58 @SuppressWarnings("unchecked") 59 public <T> T contextRemove(Class<T> clazz) { 60 if (context != null) { 61 ListIterator<Object> it = context.listIterator(); 62 while (it.hasNext()) { 63 Object e = it.next(); 64 if (clazz.isInstance(e)) { 65 // remove entry 66 it.remove(); 67 if (context.isEmpty()) { 68 context = null; 69 } 70 return (T) e; 71 } 72 } 73 } 74 return null; 75 } 76 }