// Tags: JDK1.4
// Uses: MultiplicationService MultiplierOne MultiplierTwo MultiplierThree
// Copyright (C) 2004 Sascha Brawer <brawer@dandelis.ch>
// This file is part of Mauve.
// Mauve 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.
// Mauve 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 Mauve; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.
package gnu.testlet.javax.imageio.spi.ServiceRegistry;
import gnu.testlet.Testlet;
import gnu.testlet.TestHarness;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.logging.Handler;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.logging.LogRecord;
import java.util.logging.SimpleFormatter;
import javax.imageio.spi.ServiceRegistry;
/**
* @author <a href="mailto:brawer@dandelis.ch">Sascha Brawer</a>
*/
public class lookupProviders
implements Testlet
{
public void test(TestHarness h)
{
Throwable caught;
CustomClassLoader myClassLoader;
Iterator it;
URL[] providers;
MultiplicationService s;
// Setup a bridge between java.util.logging and the debug()
// method of the passed Mauve TestHarness. Any log messages
// will be visible when running Mauve with the -debug switch.
setupLogging(h);
String packageName
= "gnu.testlet.javax.imageio.spi.ServiceRegistry";
providers = new URL[2];
try
{
providers[0] = createProviderList(new String[]
{
packageName + ".MultiplierOne",
packageName + ".MultiplierTwo"
});
providers[1] = createProviderList(new String[]
{
packageName + ".MultiplierThree"
});
}
catch (IOException ioex)
{
// There was some problem with the set-up.
h.check(false);
h.debug(ioex);
return;
}
myClassLoader = new CustomClassLoader(providers);
// Check #1: null spi --> IllegalArgumentException.
try
{
ServiceRegistry.lookupProviders(null, myClassLoader);
caught = null;
}
catch (Exception ex)
{
caught = ex;
}
h.check(caught instanceof IllegalArgumentException);
// Load some providers of MultiplicationService, while specifying
// a custom class loader.
it = ServiceRegistry.lookupProviders(MultiplicationService.class,
myClassLoader);
// Check #2.
h.check(it.hasNext());
// Check #3.
s = (MultiplicationService) it.next();
h.check(s.multiply(4, 5), 20);
// Check #4.
//
// We intentionally do not perform an instanceof check, because
// this would cause MultiplierOne to be loaded when this test case
// gets resolved (at least on some JVMs). But then, check #5 would
// fail.
h.check(s.getName(), "MultiplierOne");
// Check #5.
h.check(it.hasNext());
s = (MultiplicationService) it.next();
// Check #6.
h.check(s.getName(), "MultiplierTwo");
// Check #7.
h.check(it.hasNext());
s = (MultiplicationService) it.next();
// Check #8.
h.check(s.getName(), "MultiplierThree");
h.check(!it.hasNext());
// Check #9.
caught = null;
try
{
it.next();
}
catch (Exception ex)
{
caught = ex;
}
h.check(caught instanceof NoSuchElementException);
}
/**
* A handler for <code>java.util.logging</code> that feeds any log
* messages to the debug method of a Mauve TestHarness.
*
* @author <a href="mailto:brawer@dandelis.ch">Sascha Brawer</a>
*/
private static class DebugHandler
extends Handler
{
private final TestHarness harness;
public DebugHandler(TestHarness harness)
{
this.harness = harness;
setLevel(Level.ALL);
setFormatter(new SimpleFormatter());
}
public void publish(LogRecord rec)
{
harness.debug(getFormatter().format(rec).trim());
if (rec.getThrown() != null)
harness.debug(rec.getThrown());
}
public void flush()
{
}
public void close()
{
}
}
private void setupLogging(TestHarness harness)
{
Logger logger;
logger = Logger.getLogger("gnu.classpath");
logger.setLevel(Level.ALL);
logger.addHandler(new DebugHandler(harness));
}
private URL createProviderList(String[] listedProviders)
throws IOException
{
File f;
PrintWriter p;
f = File.createTempFile("MauveTest-", ".txt");
f.deleteOnExit();
p = new PrintWriter(new FileOutputStream(f));
p.println("# This file has been generated by the Mauve testsuite");
p.println("# while testing the mechanism for loading plug-in services.");
p.println("# (Code in " + this.getClass().getName() + ").");
p.println();
p.println("# It should be automatically deleted from the temporary");
p.println("# directory. If you happen to see this file, you probably");
p.println("# have run the Mauve testsuite with a Java Virtual Machine");
p.println("# that does not provide a correct implementaion of the method");
p.println("# java.io.File.deleteOnExit().");
p.println();
p.println("# Implementations for the plug-in service");
p.print("# ");
p.println(MultiplicationService.class.getName());
p.println();
for (int i = 0; i < listedProviders.length; i++)
p.println(listedProviders[i]);
p.close();
return f.toURL();
}
private class CustomClassLoader
extends ClassLoader
{
private final URL[] providerLists;
public CustomClassLoader(URL[] providerLists)
{
this.providerLists = providerLists;
}
private class ProviderEnumeration
implements Enumeration
{
private int next = 0;
public Object nextElement()
{
return providerLists[next++];
}
public boolean hasMoreElements()
{
return next < providerLists.length;
}
};
protected Enumeration findResources(String name)
throws IOException
{
if (name.equals("META-INF/services/gnu.testlet.javax.imageio.spi"
+ ".ServiceRegistry.MultiplicationService"))
return new ProviderEnumeration();
else
return super.findResources(name);
}
}
}