javax.xml.soap.FactoryFinder Maven / Gradle / Ivy
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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*/
package javax.xml.soap;
import java.io.*;
import java.util.Properties;
class FactoryFinder {
/**
* Creates an instance of the specified class using the specified
* ClassLoader object.
*
* @exception SOAPException if the given class could not be found
* or could not be instantiated
*/
private static Object newInstance(String className,
ClassLoader classLoader)
throws SOAPException
{
try {
Class spiClass = safeLoadClass(className, classLoader);
return spiClass.newInstance();
} catch (ClassNotFoundException x) {
throw new SOAPException("Provider " + className + " not found", x);
} catch (Exception x) {
throw new SOAPException("Provider " + className + " could not be instantiated: " + x, x);
}
}
/**
* Finds the implementation Class object for the given
* factory name, or null if that fails.
*
* This method is package private so that this code can be shared.
*
* @return the Class object of the specified message factory;
* or null
*
* @param factoryId the name of the factory to find, which is
* a system property
* @exception SOAPException if there is a SOAP error
*/
static Object find(String factoryId)
throws SOAPException
{
return find(factoryId, null, false);
}
/**
* Finds the implementation Class object for the given
* factory name, or if that fails, finds the Class object
* for the given fallback class name. The arguments supplied must be
* used in order. If using the first argument is successful, the second
* one will not be used.
*
* This method is package private so that this code can be shared.
*
* @return the Class object of the specified message factory;
* may be null
*
* @param factoryId the name of the factory to find, which is
* a system property
* @param fallbackClassName the implementation class name, which is
* to be used only if nothing else
* is found; null to indicate that
* there is no fallback class name
* @exception SOAPException if there is a SOAP error
*/
static Object find(String factoryId, String fallbackClassName)
throws SOAPException
{
return find(factoryId, fallbackClassName, true);
}
/**
* Finds the implementation Class object for the given
* factory name, or if that fails, finds the Class object
* for the given default class name, but only if tryFallback
* is true. The arguments supplied must be used in order
* If using the first argument is successful, the second one will not
* be used. Note the default class name may be needed even if fallback
* is not to be attempted, so certain error conditions can be handled.
*
* This method is package private so that this code can be shared.
*
* @return the Class object of the specified message factory;
* may not be null
*
* @param factoryId the name of the factory to find, which is
* a system property
* @param defaultClassName the implementation class name, which is
* to be used only if nothing else
* is found; null to indicate
* that there is no default class name
* @param tryFallback whether to try the default class as a
* fallback
* @exception SOAPException if there is a SOAP error
*/
static Object find(String factoryId, String defaultClassName,
boolean tryFallback) throws SOAPException {
ClassLoader classLoader;
try {
classLoader = Thread.currentThread().getContextClassLoader();
} catch (Exception x) {
throw new SOAPException(x.toString(), x);
}
// Use the system property first
try {
String systemProp =
System.getProperty( factoryId );
if( systemProp!=null) {
return newInstance(systemProp, classLoader);
}
} catch (SecurityException se) {
}
// try to read from $java.home/lib/jaxm.properties
try {
String javah=System.getProperty( "java.home" );
String configFile = javah + File.separator +
"lib" + File.separator + "jaxm.properties";
File f=new File( configFile );
if( f.exists()) {
Properties props=new Properties();
props.load( new FileInputStream(f));
String factoryClassName = props.getProperty(factoryId);
return newInstance(factoryClassName, classLoader);
}
} catch(Exception ex ) {
}
String serviceId = "META-INF/services/" + factoryId;
// try to find services in CLASSPATH
try {
InputStream is=null;
if (classLoader == null) {
is=ClassLoader.getSystemResourceAsStream(serviceId);
} else {
is=classLoader.getResourceAsStream(serviceId);
}
if( is!=null ) {
BufferedReader rd =
new BufferedReader(new InputStreamReader(is, "UTF-8"));
String factoryClassName = rd.readLine();
rd.close();
if (factoryClassName != null &&
! "".equals(factoryClassName)) {
return newInstance(factoryClassName, classLoader);
}
}
} catch( Exception ex ) {
}
// If not found and fallback should not be tried, return a null result.
if (!tryFallback)
return null;
// We didn't find the class through the usual means so try the default
// (built in) factory if specified.
if (defaultClassName == null) {
throw new SOAPException(
"Provider for " + factoryId + " cannot be found", null);
}
return newInstance(defaultClassName, classLoader);
}
/**
* Loads the class, provided that the calling thread has an access to the
* class being loaded. If this is the specified default factory class and it
* is restricted by package.access we get a SecurityException and can do a
* Class.forName() on it so it will be loaded by the bootstrap class loader.
*/
private static Class safeLoadClass(String className,
ClassLoader classLoader)
throws ClassNotFoundException {
try {
// make sure that the current thread has an access to the package of the given name.
SecurityManager s = System.getSecurityManager();
if (s != null) {
int i = className.lastIndexOf('.');
if (i != -1) {
s.checkPackageAccess(className.substring(0, i));
}
}
if (classLoader == null)
return Class.forName(className);
else
return classLoader.loadClass(className);
} catch (SecurityException se) {
// (only) default implementation can be loaded
// using bootstrap class loader:
if (isDefaultImplementation(className))
return Class.forName(className);
throw se;
}
}
private static boolean isDefaultImplementation(String className) {
return MessageFactory.DEFAULT_MESSAGE_FACTORY.equals(className) ||
SOAPFactory.DEFAULT_SOAP_FACTORY.equals(className) ||
SOAPConnectionFactory.DEFAULT_SOAP_CONNECTION_FACTORY.equals(className) ||
SAAJMetaFactory.DEFAULT_META_FACTORY_CLASS.equals(className);
}
}