src/hotspot/share/runtime/reflectionUtils.hpp
changeset 47216 71c04702a3d5
parent 46380 4a51438196cf
child 49361 1956d0ec092a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/reflectionUtils.hpp	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,234 @@
+/*
+ * Copyright (c) 1999, 2017, 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_RUNTIME_REFLECTIONUTILS_HPP
+#define SHARE_VM_RUNTIME_REFLECTIONUTILS_HPP
+
+#include "memory/allocation.hpp"
+#include "oops/instanceKlass.hpp"
+#include "oops/objArrayOop.hpp"
+#include "oops/oopsHierarchy.hpp"
+#include "runtime/handles.inline.hpp"
+#include "runtime/reflection.hpp"
+#include "utilities/accessFlags.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+// A KlassStream is an abstract stream for streaming over self, superclasses
+// and (super)interfaces. Streaming is done in reverse order (subclasses first,
+// interfaces last).
+//
+//    for (KlassStream st(k, false, false, false); !st.eos(); st.next()) {
+//      Klass* k = st.klass();
+//      ...
+//    }
+
+class KlassStream VALUE_OBJ_CLASS_SPEC {
+ protected:
+  InstanceKlass*      _klass;           // current klass/interface iterated over
+  InstanceKlass*      _base_klass;      // initial klass/interface to iterate over
+  Array<Klass*>*      _interfaces;      // transitive interfaces for initial class
+  int                 _interface_index; // current interface being processed
+  bool                _local_only;      // process initial class/interface only
+  bool                _classes_only;    // process classes only (no interfaces)
+  bool                _walk_defaults;   // process default methods
+  bool                _base_class_search_defaults; // time to process default methods
+  bool                _defaults_checked; // already checked for default methods
+  int                 _index;
+
+  virtual int length() = 0;
+
+ public:
+  // constructor
+  KlassStream(InstanceKlass* klass, bool local_only, bool classes_only, bool walk_defaults);
+
+  // testing
+  bool eos();
+
+  // iterating
+  virtual void next() = 0;
+
+  // accessors
+  InstanceKlass* klass() const      { return _klass; }
+  int index() const                 { return _index; }
+  bool base_class_search_defaults() const { return _base_class_search_defaults; }
+  void base_class_search_defaults(bool b) { _base_class_search_defaults = b; }
+};
+
+
+// A MethodStream streams over all methods in a class, superclasses and (super)interfaces.
+// Streaming is done in reverse order (subclasses first, methods in reverse order)
+// Usage:
+//
+//    for (MethodStream st(k, false, false); !st.eos(); st.next()) {
+//      Method* m = st.method();
+//      ...
+//    }
+
+class MethodStream : public KlassStream {
+ private:
+  int length()                    { return methods()->length(); }
+  Array<Method*>* methods() {
+    if (base_class_search_defaults()) {
+      base_class_search_defaults(false);
+      return _klass->default_methods();
+    } else {
+      return _klass->methods();
+    }
+  }
+ public:
+  MethodStream(InstanceKlass* klass, bool local_only, bool classes_only)
+    : KlassStream(klass, local_only, classes_only, true) {
+    _index = length();
+    next();
+  }
+
+  void next() { _index--; }
+  Method* method() { return methods()->at(index()); }
+};
+
+
+// A FieldStream streams over all fields in a class, superclasses and (super)interfaces.
+// Streaming is done in reverse order (subclasses first, fields in reverse order)
+// Usage:
+//
+//    for (FieldStream st(k, false, false); !st.eos(); st.next()) {
+//      Symbol* field_name = st.name();
+//      ...
+//    }
+
+
+class FieldStream : public KlassStream {
+ private:
+  int length() { return _klass->java_fields_count(); }
+
+  fieldDescriptor _fd_buf;
+
+ public:
+  FieldStream(InstanceKlass* klass, bool local_only, bool classes_only)
+    : KlassStream(klass, local_only, classes_only, false) {
+    _index = length();
+    next();
+  }
+
+  void next() { _index -= 1; }
+
+  // Accessors for current field
+  AccessFlags access_flags() const {
+    AccessFlags flags;
+    flags.set_flags(_klass->field_access_flags(_index));
+    return flags;
+  }
+  Symbol* name() const {
+    return _klass->field_name(_index);
+  }
+  Symbol* signature() const {
+    return _klass->field_signature(_index);
+  }
+  // missing: initval()
+  int offset() const {
+    return _klass->field_offset( index() );
+  }
+  // bridge to a heavier API:
+  fieldDescriptor& field_descriptor() const {
+    fieldDescriptor& field = const_cast<fieldDescriptor&>(_fd_buf);
+    field.reinitialize(_klass, _index);
+    return field;
+  }
+};
+
+class FilteredField : public CHeapObj<mtInternal>  {
+ private:
+  Klass* _klass;
+  int    _field_offset;
+
+ public:
+  FilteredField(Klass* klass, int field_offset) {
+    _klass = klass;
+    _field_offset = field_offset;
+  }
+  Klass* klass() { return _klass; }
+  int  field_offset() { return _field_offset; }
+};
+
+class FilteredFieldsMap : AllStatic {
+ private:
+  static GrowableArray<FilteredField *> *_filtered_fields;
+ public:
+  static void initialize();
+  static bool is_filtered_field(Klass* klass, int field_offset) {
+    for (int i=0; i < _filtered_fields->length(); i++) {
+      if (klass == _filtered_fields->at(i)->klass() &&
+        field_offset == _filtered_fields->at(i)->field_offset()) {
+        return true;
+      }
+    }
+    return false;
+  }
+  static int  filtered_fields_count(Klass* klass, bool local_only) {
+    int nflds = 0;
+    for (int i=0; i < _filtered_fields->length(); i++) {
+      if (local_only && klass == _filtered_fields->at(i)->klass()) {
+        nflds++;
+      } else if (klass->is_subtype_of(_filtered_fields->at(i)->klass())) {
+        nflds++;
+      }
+    }
+    return nflds;
+  }
+};
+
+
+// A FilteredFieldStream streams over all fields in a class, superclasses and
+// (super)interfaces. Streaming is done in reverse order (subclasses first,
+// fields in reverse order)
+//
+// Usage:
+//
+//    for (FilteredFieldStream st(k, false, false); !st.eos(); st.next()) {
+//      Symbol* field_name = st.name();
+//      ...
+//    }
+
+class FilteredFieldStream : public FieldStream {
+ private:
+  int  _filtered_fields_count;
+  bool has_filtered_field() { return (_filtered_fields_count > 0); }
+
+ public:
+  FilteredFieldStream(InstanceKlass* klass, bool local_only, bool classes_only)
+    : FieldStream(klass, local_only, classes_only) {
+    _filtered_fields_count = FilteredFieldsMap::filtered_fields_count(klass, local_only);
+  }
+  int field_count();
+  void next() {
+    _index -= 1;
+    if (has_filtered_field()) {
+      while (_index >=0 && FilteredFieldsMap::is_filtered_field((Klass*)_klass, offset())) {
+        _index -= 1;
+      }
+    }
+  }
+};
+
+#endif // SHARE_VM_RUNTIME_REFLECTIONUTILS_HPP