view agent/src/share/classes/sun/jvm/hotspot/oops/ArrayKlass.java @ 6169:cfa2c82f4c04

7175133: jinfo failed to get system properties after 6924259 Summary: String offset and count fields as fix of 6924259 were removed, and become optional. SA still use offset and count fields to read String contents and failed. Fix if they exist, use them other then use value field only to read, this keeps consistent with the changes in 6924259. Reviewed-by: dholmes, mikael Contributed-by: yumin.qi@oracle.com
author minqi
date Fri, 22 Jun 2012 15:35:30 -0700
parents c18cbe5936b8
children da91efe96a93
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/*
 * Copyright (c) 2000, 2007, 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 sun.jvm.hotspot.oops;

import java.io.*;
import java.util.*;
import sun.jvm.hotspot.utilities.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.memory.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.types.*;

// ArrayKlass is the abstract class for all array classes

public class ArrayKlass extends Klass {
  static {
    VM.registerVMInitializedObserver(new Observer() {
        public void update(Observable o, Object data) {
          initialize(VM.getVM().getTypeDataBase());
        }
      });
  }

  private static synchronized void initialize(TypeDataBase db) throws WrongTypeException {
    Type type          = db.lookupType("arrayKlass");
    dimension          = new CIntField(type.getCIntegerField("_dimension"), Oop.getHeaderSize());
    higherDimension    = new OopField(type.getOopField("_higher_dimension"), Oop.getHeaderSize());
    lowerDimension     = new OopField(type.getOopField("_lower_dimension"), Oop.getHeaderSize());
    vtableLen          = new CIntField(type.getCIntegerField("_vtable_len"), Oop.getHeaderSize());
    allocSize          = new CIntField(type.getCIntegerField("_alloc_size"), Oop.getHeaderSize());
    componentMirror    = new OopField(type.getOopField("_component_mirror"), Oop.getHeaderSize());
    javaLangCloneableName = null;
    javaLangObjectName = null;
    javaIoSerializableName = null;
  }

  ArrayKlass(OopHandle handle, ObjectHeap heap) {
    super(handle, heap);
  }

  private static CIntField dimension;
  private static OopField  higherDimension;
  private static OopField  lowerDimension;
  private static CIntField vtableLen;
  private static CIntField allocSize;
  private static OopField  componentMirror;

  public Klass getJavaSuper() {
    SystemDictionary sysDict = VM.getVM().getSystemDictionary();
    return sysDict.getObjectKlass();
  }

  public long  getDimension()       { return         dimension.getValue(this); }
  public Klass getHigherDimension() { return (Klass) higherDimension.getValue(this); }
  public Klass getLowerDimension()  { return (Klass) lowerDimension.getValue(this); }
  public long  getVtableLen()       { return         vtableLen.getValue(this); }
  public long  getAllocSize()       { return         allocSize.getValue(this); }
  public Oop   getComponentMirror() { return         componentMirror.getValue(this); }

  // constant class names - javaLangCloneable, javaIoSerializable, javaLangObject
  // Initialized lazily to avoid initialization ordering dependencies between ArrayKlass and SymbolTable
  private static Symbol javaLangCloneableName;
  private static Symbol javaLangObjectName;
  private static Symbol javaIoSerializableName;
  private static Symbol javaLangCloneableName() {
    if (javaLangCloneableName == null) {
      javaLangCloneableName = VM.getVM().getSymbolTable().probe("java/lang/Cloneable");
    }
    return javaLangCloneableName;
  }

  private static Symbol javaLangObjectName() {
    if (javaLangObjectName == null) {
      javaLangObjectName = VM.getVM().getSymbolTable().probe("java/lang/Object");
    }
    return javaLangObjectName;
  }

  private static Symbol javaIoSerializableName() {
    if (javaIoSerializableName == null) {
      javaIoSerializableName = VM.getVM().getSymbolTable().probe("java/io/Serializable");
    }
    return javaIoSerializableName;
  }

  public int getClassStatus() {
     return JVMDIClassStatus.VERIFIED | JVMDIClassStatus.PREPARED | JVMDIClassStatus.INITIALIZED;
  }

  public long computeModifierFlags() {
     return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
  }

  public long getArrayHeaderInBytes() {
    return Bits.maskBits(getLayoutHelper() >> LH_HEADER_SIZE_SHIFT, 0xFF);
  }

  public int getLog2ElementSize() {
    return Bits.maskBits(getLayoutHelper() >> LH_LOG2_ELEMENT_SIZE_SHIFT, 0xFF);
  }

  public int getElementType() {
    return Bits.maskBits(getLayoutHelper() >> LH_ELEMENT_TYPE_SHIFT, 0xFF);
  }

  boolean computeSubtypeOf(Klass k) {
    // An array is a subtype of Serializable, Clonable, and Object
    Symbol name = k.getName();
    if (name != null && (name.equals(javaIoSerializableName()) ||
                         name.equals(javaLangCloneableName()) ||
                         name.equals(javaLangObjectName()))) {
      return true;
    } else {
      return false;
    }
  }

  public void printValueOn(PrintStream tty) {
    tty.print("ArrayKlass");
  }

  public long getObjectSize() {
    return alignObjectSize(InstanceKlass.getHeaderSize() + getVtableLen() * getHeap().getOopSize());
  }

  public void iterateFields(OopVisitor visitor, boolean doVMFields) {
    super.iterateFields(visitor, doVMFields);
    if (doVMFields) {
      visitor.doCInt(dimension, true);
      visitor.doOop(higherDimension, true);
      visitor.doOop(lowerDimension, true);
      visitor.doCInt(vtableLen, true);
      visitor.doCInt(allocSize, true);
      visitor.doOop(componentMirror, true);
    }
  }
}