/*

 * Copyright (c) 2011, 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.

 *

 */

#ifndef SHARE_VM_OOPS_FIELDSTREAMS_HPP

#define SHARE_VM_OOPS_FIELDSTREAMS_HPP

#include "oops/instanceKlass.hpp"

#include "oops/fieldInfo.hpp"

// The is the base class for iteration over the fields array

// describing the declared fields in the class.  Several subclasses

// are provided depending on the kind of iteration required.  The

// JavaFieldStream is for iterating over regular Java fields and it

// generally the preferred iterator.  InternalFieldStream only

// iterates over fields that have been injected by the JVM.

// AllFieldStream exposes all fields and should only be used in rare

// cases.

class FieldStreamBase : public StackObj {

 protected:

  typeArrayHandle     _fields;

  constantPoolHandle  _constants;

  int                 _index;

  int                 _limit;

  FieldInfo* field() const { return FieldInfo::from_field_array(_fields(), _index); }

  FieldStreamBase(typeArrayHandle fields, constantPoolHandle constants, int start, int limit) {

    _fields = fields;

    _constants = constants;

    _index = start;

    _limit = limit;

  }

  FieldStreamBase(typeArrayHandle fields, constantPoolHandle constants) {

    _fields = fields;

    _constants = constants;

    _index = 0;

    _limit = fields->length() / FieldInfo::field_slots;

  }

 public:

  FieldStreamBase(instanceKlass* klass) {

    _fields = klass->fields();

    _constants = klass->constants();

    _index = 0;

    _limit = klass->java_fields_count();

  }

  FieldStreamBase(instanceKlassHandle klass) {

    _fields = klass->fields();

    _constants = klass->constants();

    _index = 0;

    _limit = klass->java_fields_count();

  }

  // accessors

  int index() const                 { return _index; }

  void next() { _index += 1; }

  bool done() const { return _index >= _limit; }

  // Accessors for current field

  AccessFlags access_flags() const {

    AccessFlags flags;

    flags.set_flags(field()->access_flags());

    return flags;

  }

  void set_access_flags(u2 flags) const {

    field()->set_access_flags(flags);

  }

  void set_access_flags(AccessFlags flags) const {

    set_access_flags(flags.as_short());

  }

  Symbol* name() const {

    return field()->name(_constants);

  }

  Symbol* signature() const {

    return field()->signature(_constants);

  }

  Symbol* generic_signature() const {

    return field()->generic_signature(_constants);

  }

  int offset() const {

    return field()->offset();

  }

  void set_offset(int offset) {

    field()->set_offset(offset);

  }

};

// Iterate over only the internal fields

class JavaFieldStream : public FieldStreamBase {

 public:

  JavaFieldStream(instanceKlass* k):      FieldStreamBase(k->fields(), k->constants(), 0, k->java_fields_count()) {}

  JavaFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants(), 0, k->java_fields_count()) {}

  int name_index() const {

    assert(!field()->is_internal(), "regular only");

    return field()->name_index();

  }

  void set_name_index(int index) {

    assert(!field()->is_internal(), "regular only");

    field()->set_name_index(index);

  }

  int signature_index() const {

    assert(!field()->is_internal(), "regular only");

    return field()->signature_index();

  }

  void set_signature_index(int index) {

    assert(!field()->is_internal(), "regular only");

    field()->set_signature_index(index);

  }

  int generic_signature_index() const {

    assert(!field()->is_internal(), "regular only");

    return field()->generic_signature_index();

  }

  void set_generic_signature_index(int index) {

    assert(!field()->is_internal(), "regular only");

    field()->set_generic_signature_index(index);

  }

  int initval_index() const {

    assert(!field()->is_internal(), "regular only");

    return field()->initval_index();

  }

  void set_initval_index(int index) {

    assert(!field()->is_internal(), "regular only");

    return field()->set_initval_index(index);

  }

};

// Iterate over only the internal fields

class InternalFieldStream : public FieldStreamBase {

 public:

  InternalFieldStream(instanceKlass* k):      FieldStreamBase(k->fields(), k->constants(), k->java_fields_count(), k->all_fields_count()) {}

  InternalFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants(), k->java_fields_count(), k->all_fields_count()) {}

};

class AllFieldStream : public FieldStreamBase {

 public:

  AllFieldStream(typeArrayHandle fields, constantPoolHandle constants): FieldStreamBase(fields, constants) {}

  AllFieldStream(instanceKlass* k):      FieldStreamBase(k->fields(), k->constants()) {}

  AllFieldStream(instanceKlassHandle k): FieldStreamBase(k->fields(), k->constants()) {}

};

#endif // SHARE_VM_OOPS_FIELDSTREAMS_HPP