Mercurial > hg > graal-jvmci-8
diff agent/src/share/classes/sun/jvm/hotspot/utilities/BasicHashtableEntry.java @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
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date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | c18cbe5936b8 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/agent/src/share/classes/sun/jvm/hotspot/utilities/BasicHashtableEntry.java Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,80 @@ +/* + * Copyright 2003-2004 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +package sun.jvm.hotspot.utilities; + +import java.util.*; +import sun.jvm.hotspot.debugger.*; +import sun.jvm.hotspot.oops.Oop; +import sun.jvm.hotspot.oops.ObjectHeap; +import sun.jvm.hotspot.types.*; +import sun.jvm.hotspot.runtime.*; + +public class BasicHashtableEntry extends VMObject { + static { + VM.registerVMInitializedObserver(new Observer() { + public void update(Observable o, Object data) { + initialize(VM.getVM().getTypeDataBase()); + } + }); + } + + private static synchronized void initialize(TypeDataBase db) { + Type type = db.lookupType("BasicHashtableEntry"); + hashField = type.getCIntegerField("_hash"); + nextField = type.getAddressField("_next"); + } + + // Fields + private static CIntegerField hashField; + private static AddressField nextField; + + // Accessors + public long hash() { + return hashField.getValue(addr) & 0xFFFFFFFFL; + } + + private long nextAddressValue() { + Debugger dbg = VM.getVM().getDebugger(); + Address nextValue = nextField.getValue(addr); + return (nextValue != null) ? dbg.getAddressValue(nextValue) : 0L; + } + + public boolean isShared() { + return (nextAddressValue() & 1L) != 0; + } + + public BasicHashtableEntry next() { + Address nextValue = nextField.getValue(addr); + Address next = (nextValue != null)? nextValue.andWithMask(-2L) : null; + // using this.getClass so that return type will be as expected in + // subclass context. But, because we can't use covariant return type + // caller has to use this next and cast the result to correct type. + return (BasicHashtableEntry) VMObjectFactory.newObject(this.getClass(), next); + } + + public BasicHashtableEntry(Address addr) { + super(addr); + } +}