[cp-patches] Patch: RFC: VMCompiler

[Tom Tromey]

For gcj-jit we may finally have a reason to use parts of
java.lang.Compiler.  In particular I'm thinking we might want to use
Compiler.enable() and Compiler.disable() to let folks indicate whether
they want gcj-jit to be used.

So, I wrote this patch to turn Compiler into a simple wrapper around
VMCompiler.  Any comments on this?

Tom

Index: ChangeLog
from  Tom Tromey  <address@hidden>

        * java/lang/Compiler.java: Rewrote in terms of VMCompiler.
        * vm/reference/java/lang/VMCompiler.java: New file.

Index: java/lang/Compiler.java
===================================================================
RCS file: /cvsroot/classpath/classpath/java/lang/Compiler.java,v
retrieving revision 1.7
diff -u -r1.7 Compiler.java
--- java/lang/Compiler.java 12 Apr 2004 14:32:59 -0000 1.7
+++ java/lang/Compiler.java 11 Aug 2004 18:14:00 -0000
@@ -1,5 +1,5 @@
 /* Compiler.java -- placeholder for Java-to-native runtime compilers
-   Copyright (C) 1998, 1999, 2001, 2002 Free Software Foundation, Inc.
+   Copyright (C) 1998, 1999, 2001, 2002, 2004 Free Software Foundation, Inc.
 
 This file is part of GNU Classpath.
 
@@ -76,8 +76,7 @@
    */
   public static boolean compileClass(Class oneClass)
   {
-    // Never succeed.
-    return false;
+    return VMCompiler.compileClass(oneClass);
   }
 
   /**
@@ -90,8 +89,7 @@
    */
   public static boolean compileClasses(String classNames)
   {
-    // Note the incredibly lame interface.  Always fail.
-    return false;
+    return VMCompiler.compileClasses(classNames);
   }
 
   /**
@@ -105,8 +103,7 @@
    */
   public static Object command(Object arg)
   {
-    // Our implementation defines this to a no-op.
-    return null;
+    return VMCompiler.command(arg);
   }
 
   /**
@@ -116,6 +113,7 @@
    */
   public static void enable()
   {
+    VMCompiler.enable();
   }
 
   /**
@@ -124,5 +122,6 @@
    */
   public static void disable()
   {
+    VMCompiler.disable();
   }
 }
Index: vm/reference/java/lang/VMCompiler.java
===================================================================
RCS file: vm/reference/java/lang/VMCompiler.java
diff -N vm/reference/java/lang/VMCompiler.java
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ vm/reference/java/lang/VMCompiler.java 11 Aug 2004 18:14:05 -0000
@@ -0,0 +1,112 @@
+/* VMClassLoader.java -- Reference implementation of compiler interface
+   Copyright (C) 2004 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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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.lang;
+
+/**
+ * This class is just a per-VM reflection of java.lang.Compiler.
+ * All methods are defined identically.
+ */
+final class VMCompiler
+{
+  /**
+   * Don't allow new `Compiler's to be made.
+   */
+  private VMCompiler()
+  {
+  }
+
+  /**
+   * Compile the class named by <code>oneClass</code>.
+   *
+   * @param oneClass the class to compile
+   * @return <code>false</code> if no compiler is available or
+   *         compilation failed, <code>true</code> if compilation succeeded
+   * @throws NullPointerException if oneClass is null
+   */
+  public static boolean compileClass(Class oneClass)
+  {
+    // Never succeed.
+    return false;
+  }
+
+  /**
+   * Compile the classes whose name matches <code>classNames</code>.
+   *
+   * @param classNames the name of classes to compile
+   * @return <code>false</code> if no compiler is available or
+   *         compilation failed, <code>true</code> if compilation succeeded
+   * @throws NullPointerException if classNames is null
+   */
+  public static boolean compileClasses(String classNames)
+  {
+    // Note the incredibly lame interface.  Always fail.
+    return false;
+  }
+
+  /**
+   * This method examines the argument and performs an operation
+   * according to the compilers documentation.  No specific operation
+   * is required.
+   *
+   * @param arg a compiler-specific argument
+   * @return a compiler-specific value, including null
+   * @throws NullPointerException if the compiler doesn't like a null arg
+   */
+  public static Object command(Object arg)
+  {
+    // Our implementation defines this to a no-op.
+    return null;
+  }
+
+  /**
+   * Calling <code>Compiler.enable()</code> will cause the compiler
+   * to resume operation if it was previously disabled; provided that a
+   * compiler even exists.
+   */
+  public static void enable()
+  {
+  }
+
+  /**
+   * Calling <code>Compiler.disable()</code> will cause the compiler
+   * to be suspended; provided that a compiler even exists.
+   */
+  public static void disable()
+  {
+  }
+}