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Diffstat (limited to 'libjava/classpath/vm/reference/java/lang/VMClassLoader.java')
| -rw-r--r-- | libjava/classpath/vm/reference/java/lang/VMClassLoader.java | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/libjava/classpath/vm/reference/java/lang/VMClassLoader.java b/libjava/classpath/vm/reference/java/lang/VMClassLoader.java new file mode 100644 index 000000000..c1d462588 --- /dev/null +++ b/libjava/classpath/vm/reference/java/lang/VMClassLoader.java @@ -0,0 +1,431 @@ +/* VMClassLoader.java -- Reference implementation of native interface + required by ClassLoader + Copyright (C) 1998, 2001, 2002, 2004, 2005, 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.lang; + +import gnu.classpath.Configuration; +import gnu.classpath.SystemProperties; +import gnu.java.lang.InstrumentationImpl; + +import java.io.BufferedReader; +import java.io.File; +import java.io.IOException; +import java.io.InputStreamReader; +import java.lang.instrument.Instrumentation; +import java.net.MalformedURLException; +import java.net.URL; +import java.security.ProtectionDomain; +import java.util.Enumeration; +import java.util.HashMap; +import java.util.HashSet; +import java.util.Map; +import java.util.Set; +import java.util.StringTokenizer; +import java.util.Vector; +import java.util.zip.ZipFile; + +/** + * 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 +{ + + + /** packages loaded by the bootstrap class loader */ + static final HashMap definedPackages = new HashMap(); + + /** jars from property java.boot.class.path */ + static final HashMap bootjars = new HashMap(); + + + /** + * Converts the array string of native package names to + * Packages. The packages are then put into the + * definedPackages hashMap + */ + static + { + String[] packages = getBootPackages(); + + if( packages != null) + { + String specName = + SystemProperties.getProperty("java.specification.name"); + String vendor = + SystemProperties.getProperty("java.specification.vendor"); + String version = + SystemProperties.getProperty("java.specification.version"); + + Package p; + + for(int i = 0; i < packages.length; i++) + { + p = new Package(packages[i], + specName, + vendor, + version, + "GNU Classpath", + "GNU", + Configuration.CLASSPATH_VERSION, + null, + null); + + definedPackages.put(packages[i], p); + } + } + } + + + /** + * Helper to define a class using a string of bytes. This assumes that + * the security checks have already been performed, if necessary. + * + * Implementations of this method are advised to consider the + * situation where user code modifies the byte array after it has + * been passed to defineClass. This can be handled by making a + * private copy of the array, or arranging to only read any given + * byte a single time. + * + * @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 c); + + /** + * 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; + + /** + * Helper to load a resource from the bootstrap class loader. + * + * @param name the resource to find + * @return the URL to the resource + */ + static URL getResource(String name) + { + Enumeration e = getResources(name); + if (e.hasMoreElements()) + return (URL)e.nextElement(); + return null; + } + /** + * Helper to get a list of resources from the bootstrap class loader. + * + * @param name the resource to find + * @return an enumeration of resources + */ + static Enumeration getResources(String name) + { + StringTokenizer st = new StringTokenizer( + SystemProperties.getProperty("java.boot.class.path", "."), + File.pathSeparator); + Vector v = new Vector(); + while (st.hasMoreTokens()) + { + File file = new File(st.nextToken()); + if (file.isDirectory()) + { + try + { + File f = new File(file, name); + if (!f.exists()) continue; + v.add(new URL("file://" + f.getAbsolutePath())); + } + catch (MalformedURLException e) + { + throw new Error(e); + } + } + else if (file.isFile()) + { + ZipFile zip; + synchronized(bootjars) + { + zip = (ZipFile) bootjars.get(file.getName()); + } + if(zip == null) + { + try + { + zip = new ZipFile(file); + synchronized(bootjars) + { + bootjars.put(file.getName(), zip); + } + } + catch (IOException e) + { + continue; + } + } + String zname = name.startsWith("/") ? name.substring(1) : name; + if (zip.getEntry(zname) == null) + continue; + try + { + v.add(new URL("jar:file://" + + file.getAbsolutePath() + "!/" + zname)); + } + catch (MalformedURLException e) + { + throw new Error(e); + } + } + } + return v.elements(); + } + + + /** + * Returns a String[] of native package names. The default + * implementation tries to load a list of package from + * the META-INF/INDEX.LIST file in the boot jar file. + * If not found or if any exception is raised, it returns + * an empty array. You may decide this needs native help. + */ + private static String[] getBootPackages() + { + URL indexList = getResource("META-INF/INDEX.LIST"); + if (indexList != null) + { + try + { + Set packageSet = new HashSet(); + String line; + int lineToSkip = 3; + BufferedReader reader = new BufferedReader( + new InputStreamReader( + indexList.openStream())); + while ((line = reader.readLine()) != null) + { + if (lineToSkip == 0) + { + if (line.length() == 0) + lineToSkip = 1; + else + packageSet.add(line.replace('/', '.')); + } + else + lineToSkip--; + } + reader.close(); + return (String[]) packageSet.toArray(new String[packageSet.size()]); + } + catch (IOException e) + { + return new String[0]; + } + } + else + return new String[0]; + } + + + /** + * Helper to get a package from the bootstrap class loader. + * + * @param name the name to find + * @return the named package, if it exists + */ + static Package getPackage(String name) + { + return (Package)definedPackages.get(name); + } + + + + /** + * Helper to get all packages from the bootstrap class loader. + * + * @return all named packages, if any exist + */ + static Package[] getPackages() + { + Package[] packages = new Package[definedPackages.size()]; + definedPackages.values().toArray(packages); + return packages; + } + + /** + * 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); + + /** + * 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; + } + + /** + * 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(); + } + + /** + * 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 new HashMap(); + } + + static ClassLoader getSystemClassLoader() + { + return ClassLoader.defaultGetSystemClassLoader(); + } + + /** + * Find the class if this class loader previously defined this class + * or if this class loader has been recorded as the initiating class loader + * for this class. + */ + static native Class findLoadedClass(ClassLoader cl, String name); + + /** + * The Instrumentation object created by the vm when agents are defined. + */ + static final Instrumentation instrumenter = null; + + /** + * Call the transformers of the possible Instrumentation object. This + * implementation assumes the instrumenter is a + * <code>InstrumentationImpl</code> object. VM implementors would + * have to redefine this method if they provide their own implementation + * of the <code>Instrumentation</code> interface. + * + * @param loader the initiating loader + * @param name the name of the class + * @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 new data representing the classfile + */ + static final Class defineClassWithTransformers(ClassLoader loader, + String name, byte[] data, int offset, int len, ProtectionDomain pd) + { + + if (instrumenter != null) + { + byte[] modifiedData = new byte[len]; + System.arraycopy(data, offset, modifiedData, 0, len); + String jvmName = name.replace('.', '/'); + modifiedData = + ((InstrumentationImpl)instrumenter).callTransformers(loader, jvmName, + null, pd, modifiedData); + + return defineClass(loader, name, modifiedData, 0, modifiedData.length, + pd); + } + else + { + return defineClass(loader, name, data, offset, len, pd); + } + } +} |