/*

 * Copyright (c) 2000, 2012, 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 sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.utilities.*;

// Super class for all fields in an object

public class Field {

  Field(FieldIdentifier id, long offset, boolean isVMField) {

    this.offset    = offset;

    this.id        = id;

    this.isVMField = isVMField;

  }

  /** Constructor for fields that are named in an InstanceKlass's

      fields array (i.e., named, non-VM fields) */

  Field(InstanceKlass holder, int fieldIndex) {

    this.holder = holder;

    this.fieldIndex = fieldIndex;

    offset               = holder.getFieldOffset(fieldIndex);

    genericSignature     = holder.getFieldGenericSignature(fieldIndex);

    Symbol name          = holder.getFieldName(fieldIndex);

    id          = new NamedFieldIdentifier(name.asString());

    signature            = holder.getFieldSignature(fieldIndex);

    fieldType   = new FieldType(signature);

    short access         = holder.getFieldAccessFlags(fieldIndex);

    accessFlags = new AccessFlags(access);

  }

  private long            offset;

  private FieldIdentifier id;

  private boolean         isVMField;

  // Java fields only

  private InstanceKlass   holder;

  private FieldType       fieldType;

  private Symbol          signature;

  private Symbol          genericSignature;

  private AccessFlags     accessFlags;

  private int             fieldIndex;

  /** Returns the byte offset of the field within the object or klass */

  public long getOffset() { return offset; }

  /** Returns the identifier of the field */

  public FieldIdentifier getID() { return id; }

  /** Indicates whether this is a VM field */

  public boolean isVMField() { return isVMField; }

  /** Indicates whether this is a named field */

  public boolean isNamedField() { return (id instanceof NamedFieldIdentifier); }

  public void printOn(PrintStream tty) {

    getID().printOn(tty);

    tty.print(" {" + getOffset() + "} :");

  }

  /** (Named, non-VM fields only) Returns the InstanceKlass containing

      this (static or non-static) field. */

  public InstanceKlass getFieldHolder() {

    return holder;

  }

  /** (Named, non-VM fields only) Returns the index in the fields

      TypeArray for this field. Equivalent to the "index" in the VM's

      fieldDescriptors. */

  public int getFieldIndex() {

    return fieldIndex;

  }

  /** (Named, non-VM fields only) Retrieves the access flags. */

  public long getAccessFlags() { return accessFlags.getValue(); }

  public AccessFlags getAccessFlagsObj() { return accessFlags; }

  /** (Named, non-VM fields only) Returns the type of this field. */

  public FieldType getFieldType() { return fieldType; }

  /** (Named, non-VM fields only) Returns the signature of this

      field. */

  public Symbol getSignature() { return signature; }

  public Symbol getGenericSignature() { return genericSignature; }

  public boolean hasInitialValue()           { return holder.getFieldInitialValueIndex(fieldIndex) != 0;    }

  //

  // Following acccessors are for named, non-VM fields only

  //

  public boolean isPublic()                  { return accessFlags.isPublic(); }

  public boolean isPrivate()                 { return accessFlags.isPrivate(); }

  public boolean isProtected()               { return accessFlags.isProtected(); }

  public boolean isPackagePrivate()          { return !isPublic() && !isPrivate() && !isProtected(); }

  public boolean isStatic()                  { return accessFlags.isStatic(); }

  public boolean isFinal()                   { return accessFlags.isFinal(); }

  public boolean isVolatile()                { return accessFlags.isVolatile(); }

  public boolean isTransient()               { return accessFlags.isTransient(); }

  public boolean isSynthetic()               { return accessFlags.isSynthetic(); }

  public boolean isEnumConstant()            { return accessFlags.isEnum();      }

  public boolean equals(Object obj) {

     if (obj == null) {

        return false;

     }

     if (! (obj instanceof Field)) {

        return false;

     }

     Field other = (Field) obj;

     return this.getFieldHolder().equals(other.getFieldHolder()) &&

            this.getID().equals(other.getID());

  }

  public int hashCode() {

     return getFieldHolder().hashCode() ^ getID().hashCode();

  }

}