//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package com.facebook.presto.jdbc.internal.jetty.util;
import java.io.File;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import com.facebook.presto.jdbc.internal.jetty.util.resource.Resource;
/* ------------------------------------------------------------ */
/** ClassLoader Helper.
* This helper class allows classes to be loaded either from the
* Thread's ContextClassLoader, the classloader of the derived class
* or the system ClassLoader.
*
* <B>Usage:</B><PRE>
* public class MyClass {
* void myMethod() {
* ...
* Class c=Loader.loadClass(this.getClass(),classname);
* ...
* }
* </PRE>
*
*/
public class Loader
{
/* ------------------------------------------------------------ */
public static URL getResource(Class<?> loadClass,String name)
{
URL url =null;
ClassLoader context_loader=Thread.currentThread().getContextClassLoader();
if (context_loader!=null)
url=context_loader.getResource(name);
if (url==null && loadClass!=null)
{
ClassLoader load_loader=loadClass.getClassLoader();
if (load_loader!=null && load_loader!=context_loader)
url=load_loader.getResource(name);
}
if (url==null)
url=ClassLoader.getSystemResource(name);
return url;
}
/* ------------------------------------------------------------ */
/** Load a class.
*
* @param loadClass
* @param name
* @return Class
* @throws ClassNotFoundException
*/
@SuppressWarnings("rawtypes")
public static Class loadClass(Class loadClass,String name)
throws ClassNotFoundException
{
ClassNotFoundException ex=null;
Class<?> c =null;
ClassLoader context_loader=Thread.currentThread().getContextClassLoader();
if (context_loader!=null )
{
try { c=context_loader.loadClass(name); }
catch (ClassNotFoundException e) {ex=e;}
}
if (c==null && loadClass!=null)
{
ClassLoader load_loader=loadClass.getClassLoader();
if (load_loader!=null && load_loader!=context_loader)
{
try { c=load_loader.loadClass(name); }
catch (ClassNotFoundException e) {if(ex==null)ex=e;}
}
}
if (c==null)
{
try { c=Class.forName(name); }
catch (ClassNotFoundException e)
{
if(ex!=null)
throw ex;
throw e;
}
}
return c;
}
/* ------------------------------------------------------------ */
public static ResourceBundle getResourceBundle(Class<?> loadClass,String name,boolean checkParents, Locale locale)
throws MissingResourceException
{
MissingResourceException ex=null;
ResourceBundle bundle =null;
ClassLoader loader=Thread.currentThread().getContextClassLoader();
while (bundle==null && loader!=null )
{
try { bundle=ResourceBundle.getBundle(name, locale, loader); }
catch (MissingResourceException e) {if(ex==null)ex=e;}
loader=(bundle==null&&checkParents)?loader.getParent():null;
}
loader=loadClass==null?null:loadClass.getClassLoader();
while (bundle==null && loader!=null )
{
try { bundle=ResourceBundle.getBundle(name, locale, loader); }
catch (MissingResourceException e) {if(ex==null)ex=e;}
loader=(bundle==null&&checkParents)?loader.getParent():null;
}
if (bundle==null)
{
try { bundle=ResourceBundle.getBundle(name, locale); }
catch (MissingResourceException e) {if(ex==null)ex=e;}
}
if (bundle!=null)
return bundle;
throw ex;
}
/* ------------------------------------------------------------ */
/**
* Generate the classpath (as a string) of all classloaders
* above the given classloader.
*
* This is primarily used for jasper.
* @return the system class path
*/
public static String getClassPath(ClassLoader loader) throws Exception
{
StringBuilder classpath=new StringBuilder();
while (loader != null && (loader instanceof URLClassLoader))
{
URL[] urls = ((URLClassLoader)loader).getURLs();
if (urls != null)
{
for (int i=0;i<urls.length;i++)
{
Resource resource = Resource.newResource(urls[i]);
File file=resource.getFile();
if (file!=null && file.exists())
{
if (classpath.length()>0)
classpath.append(File.pathSeparatorChar);
classpath.append(file.getAbsolutePath());
}
}
}
loader = loader.getParent();
}
return classpath.toString();
}
}