diff src/share/vm/oops/metadata.hpp @ 6725:da91efe96a93

6964458: Reimplement class meta-data storage to use native memory Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
author coleenp
date Sat, 01 Sep 2012 13:25:18 -0400
parents
children cd6b3f1a94ff
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/oops/metadata.hpp	Sat Sep 01 13:25:18 2012 -0400
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2011, 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.
+ *
+ */
+
+#ifndef SHARE_VM_OOPS_METADATA_HPP
+#define SHARE_VM_OOPS_METADATA_HPP
+
+#include "utilities/exceptions.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/ostream.hpp"
+
+// This is the base class for an internal Class related metadata
+class Metadata : public MetaspaceObj {
+  // Debugging hook to check that the metadata has not been deleted.
+  NOT_PRODUCT(int _valid;)
+ public:
+  NOT_PRODUCT(Metadata()     { _valid = 0; })
+  NOT_PRODUCT(bool is_valid() const volatile { return _valid == 0; })
+
+  int identity_hash()                { return (int)(uintptr_t)this; }
+
+  // Rehashing support for tables containing pointers to this
+  unsigned int new_hash(jint seed)   { ShouldNotReachHere();  return 0; }
+
+  virtual bool is_klass()              const volatile { return false; }
+  virtual bool is_method()             const volatile { return false; }
+  virtual bool is_methodData()         const volatile { return false; }
+  virtual bool is_constantPool()       const volatile { return false; }
+
+  virtual const char* internal_name()  const = 0;
+
+  void print()       const { print_on(tty); }
+  void print_value() const { print_value_on(tty); }
+
+  void print_maybe_null() const { print_on_maybe_null(tty); }
+  void print_on_maybe_null(outputStream* st) const {
+    if (this == NULL)
+      st->print("NULL");
+    else
+      print_on(tty);
+  }
+  void print_value_on_maybe_null(outputStream* st) const {
+    if (this == NULL)
+      st->print("NULL");
+    else
+      print_value_on(tty);
+  }
+
+  virtual void print_on(outputStream* st) const;       // First level print
+  virtual void print_value_on(outputStream* st) const = 0; // Second level print
+
+  char* print_value_string() const;
+
+  // Used to keep metadata alive during class redefinition
+  // Can't assert because is called for delete functions (as an assert)
+  virtual bool on_stack() const { return false; }
+  virtual void set_on_stack(const bool value);
+
+  // Set on_stack bit, so that the metadata is not cleared
+  // during class redefinition.  This is a virtual call because only methods
+  // and constant pools need to be set, but someday instanceKlasses might also.
+  static void mark_on_stack(Metadata* m) { m->set_on_stack(true); }
+};
+
+#endif // SHARE_VM_OOPS_METADATA_HPP