1 /* 2 * Copyright (c) 2000, 2015, 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 */ 24 25 package sun.jvm.hotspot.gc.shared; 26 27 import java.io.*; 28 import java.util.*; 29 30 import sun.jvm.hotspot.debugger.*; 31 import sun.jvm.hotspot.memory.*; 32 import sun.jvm.hotspot.runtime.*; 33 import sun.jvm.hotspot.types.*; 34 35 public class ContiguousSpace extends CompactibleSpace implements LiveRegionsProvider { 36 private static AddressField topField; 37 38 static { 39 VM.registerVMInitializedObserver(new Observer() { 40 public void update(Observable o, Object data) { 41 initialize(VM.getVM().getTypeDataBase()); 42 } 43 }); 44 } 45 46 private static synchronized void initialize(TypeDataBase db) { 47 Type type = db.lookupType("ContiguousSpace"); 48 49 topField = type.getAddressField("_top"); 50 } 51 52 public ContiguousSpace(Address addr) { 53 super(addr); 54 } 55 56 public Address top() { 57 return topField.getValue(addr); 58 } 59 60 /** In bytes */ 61 public long capacity() { 62 return end().minus(bottom()); 63 } 64 65 /** In bytes */ 66 public long used() { 67 return top().minus(bottom()); 68 } 69 70 /** In bytes */ 71 public long free() { 72 return end().minus(top()); 73 } 74 75 /** In a contiguous space we have a more obvious bound on what parts 76 contain objects. */ 77 public MemRegion usedRegion() { 78 return new MemRegion(bottom(), top()); 79 } 80 81 /** Returns regions of Space where live objects live */ 82 public List<MemRegion> getLiveRegions() { 83 List<MemRegion> res = new ArrayList<>(); 84 res.add(new MemRegion(bottom(), top())); 85 return res; 86 } 87 88 /** Testers */ 89 public boolean contains(Address p) { 90 return (bottom().lessThanOrEqual(p) && top().greaterThan(p)); 91 } 92 93 public void printOn(PrintStream tty) { 94 tty.print(" [" + bottom() + "," + 95 top() + "," + end() + ")"); 96 super.printOn(tty); 97 } 98 }