/*
* Copyright 2002-2010 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.core.io;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URI;
import java.net.URL;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.NestedIOException;
import org.springframework.util.ReflectionUtils;
/**
* Utility for detecting the JBoss VFS version available in the classpath.
* JBoss AS 5+ uses VFS 2.x (package <code>org.jboss.virtual</code>) while
* JBoss AS 6+ uses VFS 3.x (package <code>org.jboss.vfs</code>).
*
* <p>Thanks go to Marius Bogoevici for the initial patch.
*
* <b>Note:</b> This is an internal class and should not be used outside the framework.
*
* @author Costin Leau
* @since 3.0.3
*/
public abstract class VfsUtils {
private static final Log logger = LogFactory.getLog(VfsUtils.class);
private static final String VFS2_PKG = "org.jboss.virtual.";
private static final String VFS3_PKG = "org.jboss.vfs.";
private static final String VFS_NAME = "VFS";
private static enum VFS_VER { V2, V3 }
private static VFS_VER version;
private static Method VFS_METHOD_GET_ROOT_URL = null;
private static Method VFS_METHOD_GET_ROOT_URI = null;
private static Method VIRTUAL_FILE_METHOD_EXISTS = null;
private static Method VIRTUAL_FILE_METHOD_GET_SIZE;
private static Method VIRTUAL_FILE_METHOD_GET_LAST_MODIFIED;
private static Method VIRTUAL_FILE_METHOD_GET_CHILD;
private static Method VIRTUAL_FILE_METHOD_GET_INPUT_STREAM;
private static Method VIRTUAL_FILE_METHOD_TO_URL;
private static Method VIRTUAL_FILE_METHOD_TO_URI;
private static Method VIRTUAL_FILE_METHOD_GET_NAME;
private static Method VIRTUAL_FILE_METHOD_GET_PATH_NAME;
protected static Class<?> VIRTUAL_FILE_VISITOR_INTERFACE;
protected static Method VIRTUAL_FILE_METHOD_VISIT;
private static Method VFS_UTILS_METHOD_IS_NESTED_FILE = null;
private static Method VFS_UTILS_METHOD_GET_COMPATIBLE_URI = null;
private static Field VISITOR_ATTRIBUTES_FIELD_RECURSE = null;
private static Method GET_PHYSICAL_FILE = null;
static {
ClassLoader loader = VfsUtils.class.getClassLoader();
String pkg;
Class<?> vfsClass;
// check for JBoss 6
try {
vfsClass = loader.loadClass(VFS3_PKG + VFS_NAME);
version = VFS_VER.V3;
pkg = VFS3_PKG;
if (logger.isDebugEnabled()) {
logger.debug("JBoss VFS packages for JBoss AS 6 found");
}
}
catch (ClassNotFoundException ex) {
// fallback to JBoss 5
if (logger.isDebugEnabled())
logger.debug("JBoss VFS packages for JBoss AS 6 not found; falling back to JBoss AS 5 packages");
try {
vfsClass = loader.loadClass(VFS2_PKG + VFS_NAME);
version = VFS_VER.V2;
pkg = VFS2_PKG;
if (logger.isDebugEnabled())
logger.debug("JBoss VFS packages for JBoss AS 5 found");
} catch (ClassNotFoundException ex1) {
logger.error("JBoss VFS packages (for both JBoss AS 5 and 6) were not found - JBoss VFS support disabled");
throw new IllegalStateException("Cannot detect JBoss VFS packages", ex1);
}
}
// cache reflective information
try {
String methodName = (VFS_VER.V3.equals(version) ? "getChild" : "getRoot");
VFS_METHOD_GET_ROOT_URL = ReflectionUtils.findMethod(vfsClass, methodName, URL.class);
VFS_METHOD_GET_ROOT_URI = ReflectionUtils.findMethod(vfsClass, methodName, URI.class);
Class<?> virtualFile = loader.loadClass(pkg + "VirtualFile");
VIRTUAL_FILE_METHOD_EXISTS = ReflectionUtils.findMethod(virtualFile, "exists");
VIRTUAL_FILE_METHOD_GET_SIZE = ReflectionUtils.findMethod(virtualFile, "getSize");
VIRTUAL_FILE_METHOD_GET_INPUT_STREAM = ReflectionUtils.findMethod(virtualFile, "openStream");
VIRTUAL_FILE_METHOD_GET_LAST_MODIFIED = ReflectionUtils.findMethod(virtualFile, "getLastModified");
VIRTUAL_FILE_METHOD_TO_URI = ReflectionUtils.findMethod(virtualFile, "toURI");
VIRTUAL_FILE_METHOD_TO_URL = ReflectionUtils.findMethod(virtualFile, "toURL");
VIRTUAL_FILE_METHOD_GET_NAME = ReflectionUtils.findMethod(virtualFile, "getName");
VIRTUAL_FILE_METHOD_GET_PATH_NAME = ReflectionUtils.findMethod(virtualFile, "getPathName");
GET_PHYSICAL_FILE = ReflectionUtils.findMethod(virtualFile, "getPhysicalFile");
methodName = (VFS_VER.V3.equals(version) ? "getChild" : "findChild");
VIRTUAL_FILE_METHOD_GET_CHILD = ReflectionUtils.findMethod(virtualFile, methodName, String.class);
Class<?> utilsClass = loader.loadClass(pkg + "VFSUtils");
VFS_UTILS_METHOD_GET_COMPATIBLE_URI = ReflectionUtils.findMethod(utilsClass, "getCompatibleURI",
virtualFile);
VFS_UTILS_METHOD_IS_NESTED_FILE = ReflectionUtils.findMethod(utilsClass, "isNestedFile", virtualFile);
VIRTUAL_FILE_VISITOR_INTERFACE = loader.loadClass(pkg + "VirtualFileVisitor");
VIRTUAL_FILE_METHOD_VISIT = ReflectionUtils.findMethod(virtualFile, "visit", VIRTUAL_FILE_VISITOR_INTERFACE);
Class<?> visitorAttributesClass = loader.loadClass(pkg + "VisitorAttributes");
VISITOR_ATTRIBUTES_FIELD_RECURSE = ReflectionUtils.findField(visitorAttributesClass, "RECURSE");
}
catch (ClassNotFoundException ex) {
throw new IllegalStateException("Could not detect the JBoss VFS infrastructure", ex);
}
}
protected static Object invokeVfsMethod(Method method, Object target, Object... args) throws IOException {
try {
return method.invoke(target, args);
}
catch (InvocationTargetException ex) {
Throwable targetEx = ex.getTargetException();
if (targetEx instanceof IOException) {
throw (IOException) targetEx;
}
ReflectionUtils.handleInvocationTargetException(ex);
}
catch (Exception ex) {
ReflectionUtils.handleReflectionException(ex);
}
throw new IllegalStateException("Invalid code path reached");
}
static boolean exists(Object vfsResource) {
try {
return (Boolean) invokeVfsMethod(VIRTUAL_FILE_METHOD_EXISTS, vfsResource);
}
catch (IOException ex) {
return false;
}
}
static boolean isReadable(Object vfsResource) {
try {
return ((Long) invokeVfsMethod(VIRTUAL_FILE_METHOD_GET_SIZE, vfsResource) > 0);
}
catch (IOException ex) {
return false;
}
}
static long getLastModified(Object vfsResource) throws IOException {
return (Long) invokeVfsMethod(VIRTUAL_FILE_METHOD_GET_LAST_MODIFIED, vfsResource);
}
static InputStream getInputStream(Object vfsResource) throws IOException {
return (InputStream) invokeVfsMethod(VIRTUAL_FILE_METHOD_GET_INPUT_STREAM, vfsResource);
}
static URL getURL(Object vfsResource) throws IOException {
return (URL) invokeVfsMethod(VIRTUAL_FILE_METHOD_TO_URL, vfsResource);
}
static URI getURI(Object vfsResource) throws IOException {
return (URI) invokeVfsMethod(VIRTUAL_FILE_METHOD_TO_URI, vfsResource);
}
static String getName(Object vfsResource) {
try {
return (String) invokeVfsMethod(VIRTUAL_FILE_METHOD_GET_NAME, vfsResource);
}
catch (IOException ex) {
throw new IllegalStateException("Cannot get resource name", ex);
}
}
static Object getRelative(URL url) throws IOException {
return invokeVfsMethod(VFS_METHOD_GET_ROOT_URL, null, url);
}
static Object getChild(Object vfsResource, String path) throws IOException {
return invokeVfsMethod(VIRTUAL_FILE_METHOD_GET_CHILD, vfsResource, path);
}
static File getFile(Object vfsResource) throws IOException {
if (VFS_VER.V2.equals(version)) {
if ((Boolean) invokeVfsMethod(VFS_UTILS_METHOD_IS_NESTED_FILE, null, vfsResource)) {
throw new IOException("File resolution not supported for nested resource: " + vfsResource);
}
try {
return new File((URI) invokeVfsMethod(VFS_UTILS_METHOD_GET_COMPATIBLE_URI, null, vfsResource));
}
catch (Exception ex) {
throw new NestedIOException("Failed to obtain File reference for " + vfsResource, ex);
}
}
else {
return (File) invokeVfsMethod(GET_PHYSICAL_FILE, vfsResource);
}
}
static Object getRoot(URI url) throws IOException {
return invokeVfsMethod(VFS_METHOD_GET_ROOT_URI, null, url);
}
// protected methods used by the support sub-package
protected static Object getRoot(URL url) throws IOException {
return invokeVfsMethod(VFS_METHOD_GET_ROOT_URL, null, url);
}
protected static Object doGetVisitorAttribute() {
return ReflectionUtils.getField(VISITOR_ATTRIBUTES_FIELD_RECURSE, null);
}
protected static String doGetPath(Object resource) {
return (String) ReflectionUtils.invokeMethod(VIRTUAL_FILE_METHOD_GET_PATH_NAME, resource);
}
}
|