vm/runtime/reflectionUtils.cpp

/*
 * Copyright (c) 1999, 2010, 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.
 *
 */

#include "precompiled.hpp"
#include "classfile/javaClasses.hpp"
#include "memory/universe.inline.hpp"
#include "runtime/reflectionUtils.hpp"

KlassStream::KlassStream(instanceKlassHandle klass, bool local_only, bool classes_only) {
  _klass = klass;
  if (classes_only) {
    _interfaces = Universe::the_empty_system_obj_array();
  } else {
    _interfaces = klass->transitive_interfaces();
  }
  _interface_index = _interfaces->length();
  _local_only = local_only;
  _classes_only = classes_only;
}

bool KlassStream::eos() {
  if (index() >= 0) return false;
  if (_local_only) return true;
  if (!_klass->is_interface() && _klass->super() != NULL) {
    // go up superclass chain (not for interfaces)
    _klass = _klass->super();
  } else {
    if (_interface_index > 0) {
      _klass = klassOop(_interfaces->obj_at(--_interface_index));
    } else {
      return true;
    }
  }
  _index = length();
  next();
  return eos();
}


GrowableArray<FilteredField*> *FilteredFieldsMap::_filtered_fields =
  new (ResourceObj::C_HEAP, mtInternal) GrowableArray<FilteredField*>(3,true);


void FilteredFieldsMap::initialize() {
  int offset;
  offset = java_lang_Throwable::get_backtrace_offset();
  _filtered_fields->append(new FilteredField(SystemDictionary::Throwable_klass(), offset));
  // The latest version of vm may be used with old jdk.
  if (JDK_Version::is_gte_jdk16x_version()) {
    // The following class fields do not exist in
    // previous version of jdk.
    offset = sun_reflect_ConstantPool::cp_oop_offset();
    _filtered_fields->append(new FilteredField(SystemDictionary::reflect_ConstantPool_klass(), offset));
    offset = sun_reflect_UnsafeStaticFieldAccessorImpl::base_offset();
    _filtered_fields->append(new FilteredField(SystemDictionary::reflect_UnsafeStaticFieldAccessorImpl_klass(), offset));
  }
}

int FilteredFieldStream::field_count() {
  int numflds = 0;
  for (;!eos(); next()) {
    numflds++;
  }
  return numflds;
}