org.sonarsource.scanner.api.internal.IsolatedClassloader Maven / Gradle / Ivy
/*
* SonarQube Scanner API
* Copyright (C) 2011-2017 SonarSource SA
* mailto:info AT sonarsource DOT com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 of the License, or (at your option) any later version.
*
* This program 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.sonarsource.scanner.api.internal;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Enumeration;
import java.util.List;
/**
* Special {@link java.net.URLClassLoader} to execute batch, which restricts loading from parent.
*/
class IsolatedClassloader extends URLClassLoader {
private final ClassloadRules rules;
/**
* The parent classloader is used only for loading classes and resources in unmasked packages
*/
IsolatedClassloader(ClassLoader parent, ClassloadRules rules) {
super(new URL[0], parent);
this.rules = rules;
}
void addFiles(List files) {
try {
for (File file : files) {
addURL(file.toURI().toURL());
}
} catch (MalformedURLException e) {
throw new IllegalStateException("Fail to create classloader", e);
}
}
/**
* Same behavior as in {@link java.net.URLClassLoader#loadClass(String, boolean)}, except loading from parent.
*/
@Override
protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException {
// First, check if the class has already been loaded
Class c = findLoadedClass(name);
if (c == null) {
try {
// Load from parent
if (getParent() != null && rules.canLoad(name)) {
c = getParent().loadClass(name);
} else {
// Load from system
// I don't know for other vendors, but for Oracle JVM :
// - ClassLoader.getSystemClassLoader() is sun.misc.Launcher$AppClassLoader. It contains app classpath.
// - ClassLoader.getSystemClassLoader().getParent() is sun.misc.Launcher$ExtClassLoader. It contains core JVM
ClassLoader systemClassLoader = getSystemClassLoader();
if (systemClassLoader.getParent() != null) {
systemClassLoader = systemClassLoader.getParent();
}
c = systemClassLoader.loadClass(name);
}
} catch (ClassNotFoundException e) {
// If still not found, then invoke findClass in order
// to find the class.
c = findClass(name);
}
}
if (resolve) {
resolveClass(c);
}
return c;
}
/**
* Unlike {@link java.net.URLClassLoader#getResource(String)} don't return resource from parent.
* See http://jira.codehaus.org/browse/SONAR-2276
*/
@Override
public URL getResource(String name) {
return findResource(name);
}
/**
* Unlike {@link java.net.URLClassLoader#getResources(String)} don't return resources from parent.
* See http://jira.codehaus.org/browse/SONAR-2276
*/
@Override
public Enumeration getResources(String name) throws IOException {
return findResources(name);
}
}