-/* Copyright (C) 1999 Cygnus Solutions
+/* VMClassLoader.java -- Reference implementation of native interface
+ required by ClassLoader
+ Copyright (C) 1998, 2001, 2002, 2003, 2004, 2005 Free Software Foundation
- This file is part of libgcj.
+This file is part of GNU Classpath.
-This software is copyrighted work licensed under the terms of the
-Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
-details. */
+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.
-/* Author: Kresten Krab Thorup <krab@gnu.org> */
+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;
-import java.io.*;
+import gnu.java.util.EmptyEnumeration;
+import java.lang.reflect.Constructor;
+import java.io.File;
+import java.io.IOException;
import java.net.URL;
-import gnu.gcj.util.path.SearchPath;
+import java.net.URLClassLoader;
+import java.security.AllPermission;
+import java.security.Permission;
+import java.security.Permissions;
+import java.security.ProtectionDomain;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.StringTokenizer;
+import gnu.gcj.runtime.BootClassLoader;
-final class VMClassLoader extends java.lang.ClassLoader
+/**
+ * java.lang.VMClassLoader is a package-private helper for VMs to implement
+ * on behalf of java.lang.ClassLoader.
+ *
+ * @author John Keiser
+ * @author Mark Wielaard <mark@klomp.org>
+ * @author Eric Blake <ebb9@email.byu.edu>
+ */
+final class VMClassLoader
{
- private SearchPath path;
- private final String path_seperator;
- private final String file_seperator;
- private final char file_seperator_char;
-
- private VMClassLoader () {
- path_seperator = System.getProperty ("path.separator", ":");
- file_seperator = System.getProperty ("file.separator", "/");
-
- file_seperator_char = file_seperator.charAt (0);
-
- String class_path = System.getProperty ("java.class.path", ".");
- path = new SearchPath (class_path);
- }
+ // Protection Domain definitions
+ // FIXME: should there be a special protection domain used for native code?
+
+ // The permission required to check what a classes protection domain is.
+ static final Permission protectionDomainPermission
+ = new RuntimePermission("getProtectionDomain");
+ // The protection domain returned if we cannot determine it.
+ static ProtectionDomain unknownProtectionDomain;
- protected Class loadClass(String name,
- boolean resolve)
- throws java.lang.ClassNotFoundException, java.lang.LinkageError
+ static
{
- return loadClassInternal (name, resolve, false);
+ Permissions permissions = new Permissions();
+ permissions.add(new AllPermission());
+ unknownProtectionDomain = new ProtectionDomain(null, permissions);
}
-
- /** I'm a little in doubt here, if this method is
- actually supposed to throw a LinkageError, or not.
- The spec, 20.14.3, is a little unclear. It says:
-
- `` The general contract of loadClass is that, given the name
- of a class, it either returns the Class object for the class
- or throws a ClassNotFoundException.''
-
- However, by making LinkageError a checked exception,
- i.e., mention it directly in the throws clause,
- we'll force caller to consider that case as well.
- **/
-
- protected Class loadClassInternal(String name,
- boolean resolve,
- boolean fromBootLoader)
- throws java.lang.ClassNotFoundException, java.lang.LinkageError
- {
- Class clazz;
- /** TODO: call _Jv_VerifyClassName **/
- if ( (name.indexOf ('/') != -1)
- || (name.charAt (0) == '.')
- || (name.indexOf (file_seperator) != -1)
- || (name.indexOf ("..") != -1))
- {
- throw new IllegalArgumentException (name);
- }
+ static final HashMap definedPackages = new HashMap();
- // already loaded?
- clazz = findLoadedClass (name);
+ // This is a helper for handling java.endorsed.dirs. It is null
+ // until we've initialized the system, at which point it is created.
+ static BootClassLoader bootLoader;
- // we need access to the boot class loader here
- if (clazz == null && !fromBootLoader)
- clazz = findBootClass (name);
+ // This keeps track of shared libraries we've already tried to load.
+ private static HashSet tried_libraries;
- if (clazz == null)
+ // Holds one of the LIB_* constants; used to determine how shared
+ // library loads are done.
+ private static int lib_control;
+
+ private static final int LIB_FULL = 0;
+ private static final int LIB_CACHE = 1;
+ private static final int LIB_NEVER = 2;
+
+ /**
+ * Helper to define a class using a string of bytes. This assumes that
+ * the security checks have already been performed, if necessary.
+ *
+ * <strong>For backward compatibility, this just ignores the protection
+ * domain; that is the wrong behavior, and you should directly implement
+ * this method natively if you can.</strong>
+ *
+ * @param name the name to give the class, or null if unknown
+ * @param data the data representing the classfile, in classfile format
+ * @param offset the offset into the data where the classfile starts
+ * @param len the length of the classfile data in the array
+ * @param pd the protection domain
+ * @return the class that was defined
+ * @throws ClassFormatError if data is not in proper classfile format
+ */
+ static final native Class defineClass(ClassLoader cl, String name,
+ byte[] data, int offset, int len,
+ ProtectionDomain pd)
+ throws ClassFormatError;
+
+ /**
+ * Helper to resolve all references to other classes from this class.
+ *
+ * @param c the class to resolve
+ */
+ static final native void resolveClass(Class clazz);
+
+ static final void transformException(Class clazz, Throwable x)
+ {
+ LinkageError e;
+ if (x instanceof LinkageError)
+ e = (LinkageError) x;
+ else if (x instanceof ClassNotFoundException)
{
- StringBuffer res = new StringBuffer ();
+ e = new NoClassDefFoundError("while resolving class: "
+ + clazz.getName());
+ e.initCause (x);
+ }
+ else
+ {
+ e = new LinkageError ("unexpected exception during linking: "
+ + clazz.getName());
+ e.initCause (x);
+ }
+ throw e;
+ }
+
+ /**
+ * Helper to load a class from the bootstrap class loader.
+ *
+ * @param name the class name to load
+ * @param resolve whether to resolve it
+ * @return the class, loaded by the bootstrap classloader or null
+ * if the class wasn't found. Returning null is equivalent to throwing
+ * a ClassNotFoundException (but a possible performance optimization).
+ */
+ static final native Class loadClass(String name, boolean resolve)
+ throws ClassNotFoundException;
- // here we do actually replace .'s with /'s because
- // we're going to find something in the file system.
- res.append (name.replace ('.', file_seperator_char));
- res.append (".class");
-
- byte[] data = getResourceAsBytes (res.toString ());
+ /**
+ * Helper to load a resource from the bootstrap class loader.
+ *
+ * In libgcj, this does nothing, as the default system loader knows
+ * how to find resources that have been linked in.
+ *
+ * @param name the resource to find
+ * @return the URL to the resource
+ */
+ static URL getResource(String name)
+ {
+ if (bootLoader != null)
+ return bootLoader.bootGetResource(name);
+ return null;
+ }
- if (data == null)
- throw new ClassNotFoundException (name);
+ /**
+ * Helper to get a list of resources from the bootstrap class loader.
+ *
+ * In libgcj, this does nothing, as the default system loader knows
+ * how to find resources that have been linked in.
+ *
+ * @param name the resource to find
+ * @return an enumeration of resources
+ * @throws IOException if one occurs
+ */
+ static Enumeration getResources(String name) throws IOException
+ {
+ if (bootLoader != null)
+ return bootLoader.bootGetResources(name);
+ return EmptyEnumeration.getInstance();
+ }
- clazz = defineClass (name, data, 0, data.length);
-
+ /**
+ * Helper to get a package from the bootstrap class loader. The default
+ * implementation of returning null may be adequate, or you may decide
+ * that this needs some native help.
+ *
+ * @param name the name to find
+ * @return the named package, if it exists
+ */
+ static synchronized Package getPackage(String name)
+ {
+ return (Package) definedPackages.get(name);
+ }
+
+ /**
+ * Helper to get all packages from the bootstrap class loader. The default
+ * implementation of returning an empty array may be adequate, or you may
+ * decide that this needs some native help.
+ *
+ * @return all named packages, if any exist
+ */
+ static synchronized Package[] getPackages()
+ {
+ Package[] packages = new Package[definedPackages.size()];
+ return (Package[]) definedPackages.values().toArray(packages);
+ }
+
+ // Define a package for something loaded natively.
+ static synchronized void definePackageForNative(String className)
+ {
+ int lastDot = className.lastIndexOf('.');
+ if (lastDot != -1)
+ {
+ String packageName = className.substring(0, lastDot);
+ if (getPackage(packageName) == null)
+ {
+ // FIXME: this assumes we're defining the core, which
+ // isn't necessarily so. We could detect this and set up
+ // appropriately. We could also look at a manifest file
+ // compiled into the .so.
+ Package p = new Package(packageName,
+ "Java Platform API Specification",
+ "GNU", "1.4", "gcj", "GNU",
+ null, // FIXME: gcj version.
+ null);
+ definedPackages.put(packageName, p);
+ }
}
+ }
- if (resolve && clazz != null)
- resolveClass (clazz);
+ /**
+ * Helper for java.lang.Integer, Byte, etc to get the TYPE class
+ * at initialization time. The type code is one of the chars that
+ * represents the primitive type as in JNI.
+ *
+ * <ul>
+ * <li>'Z' - boolean</li>
+ * <li>'B' - byte</li>
+ * <li>'C' - char</li>
+ * <li>'D' - double</li>
+ * <li>'F' - float</li>
+ * <li>'I' - int</li>
+ * <li>'J' - long</li>
+ * <li>'S' - short</li>
+ * <li>'V' - void</li>
+ * </ul>
+ *
+ * @param type the primitive type
+ * @return a "bogus" class representing the primitive type
+ */
+ static final native Class getPrimitiveClass(char type);
- return clazz;
+ /**
+ * The system default for assertion status. This is used for all system
+ * classes (those with a null ClassLoader), as well as the initial value for
+ * every ClassLoader's default assertion status.
+ *
+ * XXX - Not implemented yet; this requires native help.
+ *
+ * @return the system-wide default assertion status
+ */
+ static final boolean defaultAssertionStatus()
+ {
+ return true;
}
- private native Class findBootClass (String name);
+ /**
+ * The system default for package assertion status. This is used for all
+ * ClassLoader's packageAssertionStatus defaults. It must be a map of
+ * package names to Boolean.TRUE or Boolean.FALSE, with the unnamed package
+ * represented as a null key.
+ *
+ * XXX - Not implemented yet; this requires native help.
+ *
+ * @return a (read-only) map for the default packageAssertionStatus
+ */
+ static final Map packageAssertionStatus()
+ {
+ return new HashMap();
+ }
- public InputStream getResourceAsStream(String name)
+ /**
+ * The system default for class assertion status. This is used for all
+ * ClassLoader's classAssertionStatus defaults. It must be a map of
+ * class names to Boolean.TRUE or Boolean.FALSE
+ *
+ * XXX - Not implemented yet; this requires native help.
+ *
+ * @return a (read-only) map for the default classAssertionStatus
+ */
+ static final Map classAssertionStatus()
{
- return path.getStream (name);
+ return new HashMap();
}
- public URL getResource(String name)
+ static native ClassLoader getSystemClassLoaderInternal();
+
+ static native void initBootLoader(String libdir);
+
+ static void initialize(String libdir)
{
- return path.getURL (name);
+ initBootLoader(libdir);
+
+ String p
+ = System.getProperty ("gnu.gcj.runtime.VMClassLoader.library_control",
+ "");
+ if ("never".equals(p))
+ lib_control = LIB_NEVER;
+ else if ("cache".equals(p))
+ lib_control = LIB_CACHE;
+ else if ("full".equals(p))
+ lib_control = LIB_FULL;
+ else
+ lib_control = LIB_CACHE;
+
+ tried_libraries = new HashSet();
}
- public byte[] getResourceAsBytes(String name)
+ /**
+ * Possibly load a .so and search it for classes.
+ */
+ static native Class nativeFindClass(String name);
+
+ static ClassLoader getSystemClassLoader()
{
- return path.getBytes (name);
+ // This method is called as the initialization of systemClassLoader,
+ // so if there is a null value, this is the first call and we must check
+ // for java.system.class.loader.
+ String loader = System.getProperty("java.system.class.loader");
+ ClassLoader default_sys = getSystemClassLoaderInternal();
+ if (loader != null)
+ {
+ try
+ {
+ Class load_class = Class.forName(loader, true, default_sys);
+ Constructor c
+ = load_class.getConstructor(new Class[] { ClassLoader.class });
+ default_sys
+ = (ClassLoader) c.newInstance(new Object[] { default_sys });
+ }
+ catch (Exception ex)
+ {
+ throw new Error("Failed to load requested system classloader "
+ + loader, ex);
+ }
+ }
+
+ return default_sys;
}
}
projects / gcc.git / blobdiff