/*
* Copyright (c) 2012, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package org.glassfish.jersey.server.internal.scanning;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.ReflectPermission;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.security.AccessController;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import org.glassfish.jersey.internal.OsgiRegistry;
import org.glassfish.jersey.internal.util.ReflectionHelper;
import org.glassfish.jersey.internal.util.Tokenizer;
import org.glassfish.jersey.server.internal.AbstractResourceFinderAdapter;
import org.glassfish.jersey.uri.UriComponent;
A scanner that recursively scans URI-based resources present in a set of
package names, and nested package names of that set. (Recursive scanning of
nested packages can be disabled using a proper constructor.)
The URIs for a package name are obtained, by default, by invoking ClassLoader.getResources(String)
with the parameter that is the package name with "." replaced by "/".
Each URI is then scanned using a registered UriSchemeResourceFinderFactory
that supports the URI scheme.
The following are registered by default. The FileSchemeResourceFinderFactory
for "file" URI schemes. The JarZipSchemeResourceFinderFactory
for "jar" or "zip" URI schemes to jar resources. The VfsSchemeResourceFinderFactory
for the JBoss-based "vfsfile" and "vfszip" URI schemes.
Further schemes may be registered by registering an implementation of UriSchemeResourceFinderFactory
in the META-INF/services file whose name is the the fully qualified class name of UriSchemeResourceFinderFactory
.
If a URI scheme is not supported a ResourceFinderException
will be thrown and package scanning deployment will fail.
Author: Paul Sandoz, Jakub Podlesak
/**
* A scanner that recursively scans URI-based resources present in a set of
* package names, and nested package names of that set. (Recursive scanning of
* nested packages can be disabled using a proper constructor.)
* <p>
* The URIs for a package name are obtained, by default, by invoking
* {@link ClassLoader#getResources(java.lang.String) } with the parameter that
* is the package name with "." replaced by "/".
* <p>
* Each URI is then scanned using a registered {@link UriSchemeResourceFinderFactory} that
* supports the URI scheme.
* <p>
* The following are registered by default.
* The {@link FileSchemeResourceFinderFactory} for "file" URI schemes.
* The {@link JarZipSchemeResourceFinderFactory} for "jar" or "zip" URI schemes to jar
* resources.
* The {@link VfsSchemeResourceFinderFactory} for the JBoss-based "vfsfile" and "vfszip"
* URI schemes.
* <p>
* Further schemes may be registered by registering an implementation of
* {@link UriSchemeResourceFinderFactory} in the META-INF/services file whose name is the
* the fully qualified class name of {@link UriSchemeResourceFinderFactory}.
* <p>
* If a URI scheme is not supported a {@link ResourceFinderException} will be thrown
* and package scanning deployment will fail.
*
* @author Paul Sandoz
* @author Jakub Podlesak
*/
public final class PackageNamesScanner extends AbstractResourceFinderAdapter {
private final boolean recursive;
private final String[] packages;
private final ClassLoader classloader;
private final Map<String, UriSchemeResourceFinderFactory> finderFactories;
private CompositeResourceFinder compositeResourceFinder;
Scan a set of packages using a context ClassLoader
. The recursive
flag determines whether the packages will be scanned recursively together with their nested packages (true
) or if only the specified packages shall be scanned (false
). Params: - packages – an array of package names.
- recursive – if (
true
the packages will be scanned recursively together with any nested packages, if false
only the explicitly listed packages will be scanned.
/**
* Scan a set of packages using a context {@link ClassLoader}.
*
* The {@code recursive} flag determines whether the packages will be scanned recursively
* together with their nested packages ({@code true}) or if only the specified packages
* shall be scanned ({@code false}).
*
* @param packages an array of package names.
* @param recursive if ({@code true} the packages will be scanned recursively together with
* any nested packages, if {@code false} only the explicitly listed packages
* will be scanned.
*/
public PackageNamesScanner(final String[] packages, final boolean recursive) {
this(AccessController.doPrivileged(ReflectionHelper.getContextClassLoaderPA()),
Tokenizer.tokenize(packages, Tokenizer.COMMON_DELIMITERS), recursive);
}
Scan a set of packages using the provided ClassLoader
. The recursive
flag determines whether the packages will be scanned recursively together with their nested packages (true
) or if only the specified packages shall be scanned (false
). Params: - classLoader – the
ClassLoader
to load classes from. - packages – an array of package names.
- recursive – if (
true
the packages will be scanned recursively together with any nested packages, if false
only the explicitly listed packages will be scanned.
/**
* Scan a set of packages using the provided {@link ClassLoader}.
*
* The {@code recursive} flag determines whether the packages will be scanned recursively
* together with their nested packages ({@code true}) or if only the specified packages
* shall be scanned ({@code false}).
*
* @param classLoader the {@link ClassLoader} to load classes from.
* @param packages an array of package names.
* @param recursive if ({@code true} the packages will be scanned recursively together with
* any nested packages, if {@code false} only the explicitly listed packages
* will be scanned.
*/
public PackageNamesScanner(final ClassLoader classLoader, final String[] packages, final boolean recursive) {
this.recursive = recursive;
this.packages = packages.clone();
this.classloader = classLoader;
this.finderFactories = new HashMap<>();
add(new JarZipSchemeResourceFinderFactory());
add(new FileSchemeResourceFinderFactory());
add(new VfsSchemeResourceFinderFactory());
add(new BundleSchemeResourceFinderFactory());
// TODO - Services?
// for (UriSchemeResourceFinderFactory s : ServiceFinder.find(UriSchemeResourceFinderFactory.class)) {
// add(s);
// }
final OsgiRegistry osgiRegistry = ReflectionHelper.getOsgiRegistryInstance();
if (osgiRegistry != null) {
setResourcesProvider(new PackageNamesScanner.ResourcesProvider() {
@Override
public Enumeration<URL> getResources(final String packagePath, final ClassLoader classLoader) throws IOException {
return osgiRegistry.getPackageResources(packagePath, classLoader, recursive);
}
});
}
init();
}
private void add(final UriSchemeResourceFinderFactory uriSchemeResourceFinderFactory) {
for (final String scheme : uriSchemeResourceFinderFactory.getSchemes()) {
finderFactories.put(scheme.toLowerCase(Locale.ROOT), uriSchemeResourceFinderFactory);
}
}
@Override
public boolean hasNext() {
return compositeResourceFinder.hasNext();
}
@Override
public String next() {
return compositeResourceFinder.next();
}
@Override
public InputStream open() {
return compositeResourceFinder.open();
}
@Override
public void close() {
compositeResourceFinder.close();
}
@Override
public void reset() {
close();
init();
}
public ClassLoader getClassloader() {
return classloader;
}
private void init() {
compositeResourceFinder = new CompositeResourceFinder();
for (final String p : packages) {
try {
final Enumeration<URL> urls =
ResourcesProvider.getInstance().getResources(p.replace('.', '/'), classloader);
while (urls.hasMoreElements()) {
try {
addResourceFinder(toURI(urls.nextElement()));
} catch (final URISyntaxException e) {
throw new ResourceFinderException("Error when converting a URL to a URI", e);
}
}
} catch (final IOException e) {
throw new ResourceFinderException("IO error when package scanning jar", e);
}
}
}
Find resources with a given name and class loader.
/**
* Find resources with a given name and class loader.
*/
public abstract static class ResourcesProvider {
private static volatile ResourcesProvider provider;
private static ResourcesProvider getInstance() {
// Double-check idiom for lazy initialization
ResourcesProvider result = provider;
if (result == null) { // first check without locking
synchronized (ResourcesProvider.class) {
result = provider;
if (result == null) { // second check with locking
provider = result = new ResourcesProvider() {
@Override
public Enumeration<URL> getResources(final String name, final ClassLoader cl)
throws IOException {
return cl.getResources(name);
}
};
}
}
}
return result;
}
private static void setInstance(final ResourcesProvider provider) throws SecurityException {
final SecurityManager security = System.getSecurityManager();
if (security != null) {
final ReflectPermission rp = new ReflectPermission("suppressAccessChecks");
security.checkPermission(rp);
}
synchronized (ResourcesProvider.class) {
ResourcesProvider.provider = provider;
}
}
Find all resources with the given name using a class loader.
Params: - cl – the class loader use to find the resources
- name – the resource name
Throws: - IOException – if I/O errors occur
Returns: An enumeration of URL objects for the resource.
If no resources could be found, the enumeration will be empty.
Resources that the class loader doesn't have access to will
not be in the enumeration.
/**
* Find all resources with the given name using a class loader.
*
* @param cl the class loader use to find the resources
* @param name the resource name
* @return An enumeration of URL objects for the resource.
* If no resources could be found, the enumeration will be empty.
* Resources that the class loader doesn't have access to will
* not be in the enumeration.
* @throws IOException if I/O errors occur
*/
public abstract Enumeration<URL> getResources(String name, ClassLoader cl) throws IOException;
}
Set the ResourcesProvider
implementation to find resources.
This method should be invoked before any package scanning is performed
otherwise the functionality method will be utilized.
Params: - provider – the resources provider.
Throws: - SecurityException – if the resources provider cannot be set.
/**
* Set the {@link ResourcesProvider} implementation to find resources.
* <p>
* This method should be invoked before any package scanning is performed
* otherwise the functionality method will be utilized.
*
* @param provider the resources provider.
* @throws SecurityException if the resources provider cannot be set.
*/
public static void setResourcesProvider(final ResourcesProvider provider) throws SecurityException {
ResourcesProvider.setInstance(provider);
}
private void addResourceFinder(final URI u) {
final UriSchemeResourceFinderFactory finderFactory = finderFactories.get(u.getScheme().toLowerCase(Locale.ROOT));
if (finderFactory != null) {
compositeResourceFinder.push(finderFactory.create(u, recursive));
} else {
throw new ResourceFinderException("The URI scheme " + u.getScheme()
+ " of the URI " + u
+ " is not supported. Package scanning deployment is not"
+ " supported for such URIs."
+ "\nTry using a different deployment mechanism such as"
+ " explicitly declaring root resource and provider classes"
+ " using an extension of javax.ws.rs.core.Application");
}
}
private URI toURI(final URL url) throws URISyntaxException {
try {
return url.toURI();
} catch (final URISyntaxException e) {
// Work around bug where some URLs are incorrectly encoded.
// This can occur when certain class loaders are utilized
// to obtain URLs for resources.
return URI.create(toExternalForm(url));
}
}
private String toExternalForm(final URL u) {
// pre-compute length of StringBuffer
int len = u.getProtocol().length() + 1;
if (u.getAuthority() != null && u.getAuthority().length() > 0) {
len += 2 + u.getAuthority().length();
}
if (u.getPath() != null) {
len += u.getPath().length();
}
if (u.getQuery() != null) {
len += 1 + u.getQuery().length();
}
if (u.getRef() != null) {
len += 1 + u.getRef().length();
}
final StringBuilder result = new StringBuilder(len);
result.append(u.getProtocol());
result.append(":");
if (u.getAuthority() != null && u.getAuthority().length() > 0) {
result.append("//");
result.append(u.getAuthority());
}
if (u.getPath() != null) {
result.append(UriComponent.contextualEncode(u.getPath(), UriComponent.Type.PATH));
}
if (u.getQuery() != null) {
result.append('?');
result.append(UriComponent.contextualEncode(u.getQuery(), UriComponent.Type.QUERY));
}
if (u.getRef() != null) {
result.append("#");
result.append(u.getRef());
}
return result.toString();
}
}