[cp-patches] [generics] Patch: RFC: import jsr166

Tom Tromey tromey at redhat.com
Thu May 25 15:55:32 UTC 2006


I'm not checking this in yet.  I wanted comments first.

I haven't yet written a ChangeLog entry.

This patch imports the jsr166 reference implementation.  This is
implements java.util.concurrency.

It consists of several related changes:

* A sanitize-jsr166 script which is run on a pristine download in
  order to remove copyrighted code and to change sun.* references to
  the appropriate gnu.* references.

* A small addition to VMStackWalker to support the above.  The new
  method is written in java so should not cause a big problem.

* Import of the RI code (after running the sanitize script).
  There are a couple minor hand-written changes as well, one to work
  around an apparent ecj bug.
  The upstream code goes in external/jsr166/

* Removal of our versions of some classes provided with the RI:
  AbstractQueue and Queue.

* Addition of a replacement class removed by sanitization,
  CopyOnWriteArrayList.

I'm not including the jsr166 code itself in the appended.  The
resulting patch is simply too big, compressed it is still > 200k.
However, I'm happy to send it if people really want that.

I have not tested the result at all.  Until some VM supports the
Unsafe API, I don't think there is a way to.  I think getting this on
the generics branch is probably the best way to enable VM implementors
to do this.

When this goes in I intend to check in the VMStackWalker to cvs trunk
as well, to keep the VM APIs aligned.

Tom

Index: vm/reference/gnu/classpath/VMStackWalker.java
===================================================================
RCS file: /cvsroot/classpath/classpath/vm/reference/gnu/classpath/VMStackWalker.java,v
retrieving revision 1.3.2.4
diff -u -r1.3.2.4 VMStackWalker.java
--- vm/reference/gnu/classpath/VMStackWalker.java	27 Nov 2005 21:00:42 -0000	1.3.2.4
+++ vm/reference/gnu/classpath/VMStackWalker.java	25 May 2006 15:39:58 -0000
@@ -37,6 +37,8 @@
 
 package gnu.classpath;
 
+import java.lang.reflect.Modifier;
+
 /**
  * This class provides access to the classes on the Java stack
  * for reflection and security purposes.
@@ -112,5 +114,39 @@
    * is here to work around access permissions.
    */
   public static native ClassLoader getClassLoader(Class cl);
-}
 
+  /**
+   * Perform access checks on a member of a class.  This API is
+   * derived from the public domain code in the JSR 166 reference
+   * implementation.
+   * @param caller the class requesting access to the member
+   * @param declarer the declaring class of the member
+   * @param ignored unknown parameter; always null
+   * @param modifiers the modifiers on the member
+   * @return true if access is granted, false otherwise
+   */
+  public static boolean verifyMemberAccess(Class caller,
+                                           Class declarer,
+                                           Object ignored,
+                                           int modifiers)
+  {
+    // Same class, always ok.
+    if (caller == declarer)
+      return true;
+    // Public access is ok.
+    if ((modifiers & Modifier.PUBLIC) != 0)
+      return true;
+    // Protected access and request comes from
+    // a subclass of the declarer -- ok.
+    if ((modifiers & Modifier.PROTECTED) != 0
+        && declarer.isAssignableFrom(caller))
+      return true;
+    // Package-private access, or protected access,
+    // and the packages are the same --ok.
+    if ((modifiers & Modifier.PRIVATE) == 0
+        && caller.getPackage() == declarer.getPackage())
+      return true;
+    // Otherwise, no.
+    return false;
+  }
+}
Index: external/jsr166/IMPORTING
===================================================================
RCS file: external/jsr166/IMPORTING
diff -N external/jsr166/IMPORTING
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ external/jsr166/IMPORTING	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,28 @@
+The code in this directory comes from the JSR 166
+reference implementation.  The RI consists of a public
+domain part and a part that is copyright Sun.  We remove
+the copyrighted code prior to import so as not to taint
+our source repository.  Also, we slightly modify the
+resulting untainted code so that it does not refer to
+APIs in the sun.* namespace.
+
+To do a new import:
+
+* Download the RI from the source repository.
+  http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/main/java
+  I clicked on the "download tarball" link.
+
+* Unpack the tarball in a fresh directory.
+  mkdir tmp; cd tmp; tar zxvvf .../java.tar.gz
+
+* Clean up the results.
+  .../classpath/scripts/sanitize-jsr166
+
+* Copy the result into this directory and perform the
+  appropriate cvs rm and cvs add operations
+
+* Build the result.
+
+In general we try to avoid divergence from upstream as much
+as possible.  You may need to write new classes or methods in
+order for the build to succeed.
Index: external/jsr166/readme
===================================================================
RCS file: external/jsr166/readme
diff -N external/jsr166/readme
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ external/jsr166/readme	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,45 @@
+The software comprising JSR166 was written by Doug Lea with assistance
+from members of JCP JSR-166 Expert roup and released to the public
+domain, as explained at:
+http://creativecommons.org/licenses/publicdomain, excepting portions
+of the class java.util.concurrent.CopyOnWriteArrayList, which were
+adapted from class java.util.ArrayList, written by Sun Microsystems,
+Inc, which are used with kind permission, and subject to the
+following:
+
+Copyright 2002-2004 Sun Microsystems, Inc. All rights reserved. Use is
+subject to the following license terms.
+
+  "Sun hereby grants you a non-exclusive, worldwide, non-transferrable
+  license to use and distribute the Java Software technologies as part
+  of a larger work in source and binary forms, with or without
+  modification, provided that the following conditions are met:
+
+   -Neither the name of or trademarks of Sun may be used to endorse or
+    promote products derived from the Java Software technology without
+    specific prior written permission.
+
+   -Redistributions of source or binary code must be accompanied by the
+    following notice and disclaimers:
+
+    Portions copyright Sun Microsystems, Inc. Used with kind permission.
+
+    This software is provided AS IS, without a warranty of any kind.  ALL
+    EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
+    WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PUPOSE OR
+    NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
+    MICROSYSTEMS, INC. AND ITS LICENSORS SHALL NOT BE LIABLE
+    FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF
+    USING, MODIFYING OR DISTRIBUTING THE SOFTWARE OR ITS
+    DERIVATIVES. IN NO EVENT WILL SUN MICROSYSTEMS, INC. OR
+    ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR
+    DATA, OR FOR DIRECT, INDIRECT,CONSQUENTIAL, INCIDENTAL
+    OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF
+    THE THEORY OR LIABILITY, ARISING OUT OF THE USE OF OR
+    INABILITY TO USE SOFTWARE, EVEN IF SUN MICROSYSTEMS, INC.
+    HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+
+    You acknowledge that Software is not designed, licensed or intended for
+    use in the design, construction, operation or maintenance of any nuclear
+    facility."
Index: java/util/concurrent/CopyOnWriteArrayList.java
===================================================================
RCS file: java/util/concurrent/CopyOnWriteArrayList.java
diff -N java/util/concurrent/CopyOnWriteArrayList.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ java/util/concurrent/CopyOnWriteArrayList.java	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,438 @@
+/* CopyOnWriteArrayList.java
+   Copyright (C) 2006 Free Software Foundation
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+package java.util.concurrent;
+
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+import java.lang.reflect.Array;
+import java.util.AbstractList;
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+import java.util.RandomAccess;
+
+/** @since 1.5 */
+public class CopyOnWriteArrayList<E> extends AbstractList<E> implements
+    List<E>, RandomAccess, Cloneable, Serializable
+{
+  /**
+   * Where the data is stored.
+   */
+  private transient E[] data;
+
+  /**
+   * Construct a new ArrayList with the default capacity (16).
+   */
+  public CopyOnWriteArrayList()
+  {
+    data = (E[]) new Object[0];
+  }
+
+  /**
+   * Construct a new ArrayList, and initialize it with the elements in the
+   * supplied Collection. The initial capacity is 110% of the Collection's size.
+   * 
+   * @param c
+   *          the collection whose elements will initialize this list
+   * @throws NullPointerException
+   *           if c is null
+   */
+  public CopyOnWriteArrayList(Collection< ? extends E> c)
+  {
+    // FIXME ... correct?  use c.toArray()
+    data = (E[]) new Object[c.size()];
+    int index = 0;
+    for (E value : c)
+      data[index++] = value;
+  }
+
+  /**
+   * Returns the number of elements in this list.
+   * 
+   * @return the list size
+   */
+  public int size()
+  {
+    return data.length;
+  }
+
+  /**
+   * Checks if the list is empty.
+   * 
+   * @return true if there are no elements
+   */
+  public boolean isEmpty()
+  {
+    return data.length == 0;
+  }
+
+  /**
+   * Returns true iff element is in this ArrayList.
+   * 
+   * @param e
+   *          the element whose inclusion in the List is being tested
+   * @return true if the list contains e
+   */
+  public boolean contains(Object e)
+  {
+    return indexOf(e) != -1;
+  }
+
+  /**
+   * Returns the lowest index at which element appears in this List, or -1 if it
+   * does not appear.
+   * 
+   * @param e
+   *          the element whose inclusion in the List is being tested
+   * @return the index where e was found
+   */
+  public int indexOf(Object e)
+  {
+    E[] data = this.data;
+    for (int i = 0; i < data.length; i++)
+      if (equals(e, data[i]))
+        return i;
+    return -1;
+  }
+
+  /**
+   * Returns the highest index at which element appears in this List, or -1 if
+   * it does not appear.
+   * 
+   * @param e
+   *          the element whose inclusion in the List is being tested
+   * @return the index where e was found
+   */
+  public int lastIndexOf(Object e)
+  {
+    E[] data = this.data;
+    for (int i = data.length - 1; i >= 0; i--)
+      if (equals(e, data[i]))
+        return i;
+    return -1;
+  }
+
+  /**
+   * Creates a shallow copy of this ArrayList (elements are not cloned).
+   * 
+   * @return the cloned object
+   */
+  public Object clone()
+  {
+    CopyOnWriteArrayList<E> clone = null;
+    try
+      {
+        clone = (CopyOnWriteArrayList<E>) super.clone();
+        clone.data = (E[]) data.clone();
+      }
+    catch (CloneNotSupportedException e)
+      {
+        // Impossible to get here.
+      }
+    return clone;
+  }
+
+  /**
+   * Returns an Object array containing all of the elements in this ArrayList.
+   * The array is independent of this list.
+   * 
+   * @return an array representation of this list
+   */
+  public Object[] toArray()
+  {
+    E[] data = this.data;
+    E[] array = (E[]) new Object[data.length];
+    System.arraycopy(data, 0, array, 0, data.length);
+    return array;
+  }
+
+  /**
+   * Returns an Array whose component type is the runtime component type of the
+   * passed-in Array. The returned Array is populated with all of the elements
+   * in this ArrayList. If the passed-in Array is not large enough to store all
+   * of the elements in this List, a new Array will be created and returned; if
+   * the passed-in Array is <i>larger</i> than the size of this List, then
+   * size() index will be set to null.
+   * 
+   * @param a
+   *          the passed-in Array
+   * @return an array representation of this list
+   * @throws ArrayStoreException
+   *           if the runtime type of a does not allow an element in this list
+   * @throws NullPointerException
+   *           if a is null
+   */
+  public <T> T[] toArray(T[] a)
+  {
+    E[] data = this.data;
+    if (a.length < data.length)
+      a = (T[]) Array.newInstance(a.getClass().getComponentType(), data.length);
+    else if (a.length > data.length)
+      a[data.length] = null;
+    System.arraycopy(data, 0, a, 0, data.length);
+    return a;
+  }
+
+  /**
+   * Retrieves the element at the user-supplied index.
+   * 
+   * @param index
+   *          the index of the element we are fetching
+   * @throws IndexOutOfBoundsException
+   *           if index &lt; 0 || index &gt;= size()
+   */
+  public E get(int index)
+  {
+    return data[index];
+  }
+
+  /**
+   * Sets the element at the specified index. The new element, e, can be an
+   * object of any type or null.
+   * 
+   * @param index
+   *          the index at which the element is being set
+   * @param e
+   *          the element to be set
+   * @return the element previously at the specified index
+   * @throws IndexOutOfBoundsException
+   *           if index &lt; 0 || index &gt;= 0
+   */
+  public synchronized E set(int index, E e)
+  {
+    E result = data[index];
+    E[] newData = data.clone();
+    newData[index] = e;
+    data = newData;
+    return result;
+  }
+
+  /**
+   * Appends the supplied element to the end of this list. The element, e, can
+   * be an object of any type or null.
+   * 
+   * @param e
+   *          the element to be appended to this list
+   * @return true, the add will always succeed
+   */
+  public synchronized boolean add(E e)
+  {
+    E[] data = this.data;
+    E[] newData = (E[]) new Object[data.length];
+    System.arraycopy(data, 0, newData, 0, data.length);
+    newData[data.length] = e;
+    this.data = newData;
+    return true;
+  }
+
+  /**
+   * Adds the supplied element at the specified index, shifting all elements
+   * currently at that index or higher one to the right. The element, e, can be
+   * an object of any type or null.
+   * 
+   * @param index
+   *          the index at which the element is being added
+   * @param e
+   *          the item being added
+   * @throws IndexOutOfBoundsException
+   *           if index &lt; 0 || index &gt; size()
+   */
+  public synchronized void add(int index, E e)
+  {
+    E[] data = this.data;
+    E[] newData = (E[]) new Object[data.length];
+    System.arraycopy(data, 0, newData, 0, index);
+    newData[index] = e;
+    System.arraycopy(data, index, newData, index + 1, data.length - index);
+    this.data = newData;
+  }
+
+  /**
+   * Removes the element at the user-supplied index.
+   * 
+   * @param index
+   *          the index of the element to be removed
+   * @return the removed Object
+   * @throws IndexOutOfBoundsException
+   *           if index &lt; 0 || index &gt;= size()
+   */
+  public synchronized E remove(int index)
+  {
+    E[] data = this.data;
+    E[] newData = (E[]) new Object[data.length - 1];
+    System.arraycopy(data, 0, newData, 0, index - 1);
+    System.arraycopy(data, index + 1, newData, index,
+                     data.length - index - 1);
+    E r = data[index];
+    this.data = newData;
+    return r;
+  }
+
+  /**
+   * Removes all elements from this List
+   */
+  public synchronized void clear()
+  {
+    data = (E[]) new Object[0];
+  }
+
+  /**
+   * Add each element in the supplied Collection to this List. It is undefined
+   * what happens if you modify the list while this is taking place; for
+   * example, if the collection contains this list. c can contain objects of any
+   * type, as well as null values.
+   * 
+   * @param c
+   *          a Collection containing elements to be added to this List
+   * @return true if the list was modified, in other words c is not empty
+   * @throws NullPointerException
+   *           if c is null
+   */
+  public synchronized boolean addAll(Collection< ? extends E> c)
+  {
+    return addAll(data.length, c);
+  }
+
+  /**
+   * Add all elements in the supplied collection, inserting them beginning at
+   * the specified index. c can contain objects of any type, as well as null
+   * values.
+   * 
+   * @param index
+   *          the index at which the elements will be inserted
+   * @param c
+   *          the Collection containing the elements to be inserted
+   * @throws IndexOutOfBoundsException
+   *           if index &lt; 0 || index &gt; 0
+   * @throws NullPointerException
+   *           if c is null
+   */
+  public synchronized boolean addAll(int index, Collection< ? extends E> c)
+  {
+    E[] data = this.data;
+    Iterator<? extends E> itr = c.iterator();
+    int csize = c.size();
+    if (csize == 0)
+      return false;
+
+    E[] newData = (E[]) new Object[data.length + csize];
+    System.arraycopy(data, 0, newData, 0, data.length);
+    int end = data.length;
+    for (E value : c)
+      newData[end++] = value;
+    this.data = newData;
+    return true;
+  }
+  
+  public synchronized boolean addIfAbsent(E val)
+  {
+    if (contains(val))
+      return false;
+    add(val);
+    return true;
+  }
+
+  public synchronized int addAllAbsent(Collection<? extends E> c)
+  {
+    int result = 0;
+    for (E val : c)
+      {
+        if (addIfAbsent(val))
+          ++result;
+      }
+    return result;
+  }
+
+  /**
+   * Serializes this object to the given stream.
+   * 
+   * @param s
+   *          the stream to write to
+   * @throws IOException
+   *           if the underlying stream fails
+   * @serialData the size field (int), the length of the backing array (int),
+   *             followed by its elements (Objects) in proper order.
+   */
+  private void writeObject(ObjectOutputStream s) throws IOException
+  {
+    // The 'size' field.
+    s.defaultWriteObject();
+    // We serialize unused list entries to preserve capacity.
+    int len = data.length;
+    s.writeInt(len);
+    // it would be more efficient to just write "size" items,
+    // this need readObject read "size" items too.
+    for (int i = 0; i < data.length; i++)
+      s.writeObject(data[i]);
+  }
+
+  /**
+   * Deserializes this object from the given stream.
+   * 
+   * @param s
+   *          the stream to read from
+   * @throws ClassNotFoundException
+   *           if the underlying stream fails
+   * @throws IOException
+   *           if the underlying stream fails
+   * @serialData the size field (int), the length of the backing array (int),
+   *             followed by its elements (Objects) in proper order.
+   */
+  private void readObject(ObjectInputStream s) throws IOException,
+      ClassNotFoundException
+  {
+    // the `size' field.
+    s.defaultReadObject();
+    int capacity = s.readInt();
+    data = (E[]) new Object[capacity];
+    for (int i = 0; i < capacity; i++)
+      data[i] = (E) s.readObject();
+  }
+
+  static final boolean equals(Object o1, Object o2)
+  {
+    return o1 == null ? o2 == null : o1.equals(o2);
+  }
+  
+  Object[] getArray()
+  {
+    return data;
+  }
+}
Index: scripts/sanitize-jsr166
===================================================================
RCS file: scripts/sanitize-jsr166
diff -N scripts/sanitize-jsr166
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ scripts/sanitize-jsr166	1 Jan 1970 00:00:00 -0000
@@ -0,0 +1,13 @@
+#! /bin/sh
+
+# Sanitize a jsr166 download.
+
+# Remove code copyright Sun.
+find . -name '*.java' -print | xargs grep -l 'Copyright.*Sun' | xargs rm
+
+# Change to use the Classpath Unsafe class.
+perl -pi~ -e'
+  s/import sun\.misc\.Unsafe/import gnu.classpath.Unsafe/;
+  s/sun\.reflect\.Reflection\.getCallerClass\(3\)/gnu.classpath.VMStackWalker.getClassContext()[2]/;
+  s/sun\.reflect\.Reflection\./gnu.classpath.VMStackWalker./;
+' `find . -name '*.java' -print`



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