/*
 * Copyright (c) 2016, 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
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 * questions.
 */
package jdk.vm.ci.hotspot;

Describes a C++ field exposed via HotSpotVMConfigAccess.
/** * Describes a C++ field exposed via {@link HotSpotVMConfigAccess}. */
public final class VMField {
Fully qualified name of the represented field (e.g., "Klass::_name").
/** * Fully qualified name of the represented field (e.g., "Klass::_name"). */
public final String name;
The represented field's type (e.g., "Symbol*"). This may be null.
/** * The represented field's type (e.g., "Symbol*"). This may be {@code null}. */
public final String type;
If the represented field is non-static, this is its offset within the containing structure.
/** * If the represented field is non-static, this is its offset within the containing structure. */
public final long offset;
If the represented field is static, this is its address. Otherwise, this is 0.
/** * If the represented field is static, this is its address. Otherwise, this is 0. */
public final long address;
Value of the field represented as a boxed boolean if its C++ type is bool otherwise as a boxed long; only valid for non-oop static fields. This value is only captured once, during JVMCI initialization. If type cannot be meaningfully (e.g., a struct) or safely (e.g., an oop) expressed as a boxed object, this is null.
/** * Value of the field represented as a boxed boolean if its C++ type is bool otherwise as a * boxed long; only valid for non-oop static fields. This value is only captured once, during * JVMCI initialization. If {@link #type} cannot be meaningfully (e.g., a struct) or safely * (e.g., an oop) expressed as a boxed object, this is {@code null}. */
public final Object value;
Determines if the represented field is static.
/** * Determines if the represented field is static. */
public boolean isStatic() { return address != 0; }
Creates a description of a field.
/** * Creates a description of a field. */
VMField(String name, String type, long address, Object value) { this.name = name; this.type = type; this.offset = 0; this.address = address; this.value = value; } @Override public String toString() { String val = value == null ? "null" : String.format("0x%x", value); return String.format("Field[name=%s, type=%s, offset=%d, address=0x%x, value=%s]", name, type, offset, address, val); } }