com.sun.webui.jsf.util.ClassLoaderFinder Maven / Gradle / Ivy
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package com.sun.webui.jsf.util;
/**
* Strategies for finding the current ClassLoader such as
* Thread.currentThread().getContextClassLoader()
* do not work during design time, where the notion of the
* classpath is more constrained. Please make sure you use
* this utility when you need to get hold of the current loader.
*/
public class ClassLoaderFinder {
/**
* Optional Special ClassLoader to use. For example, at
* designtime the Creator IDE will set it to the project classloader -
* and will reset it whenever
* FacesContainer.initialize() is called.
*/
private static ClassLoader customClassLoader = null;
/**
* Set a preferred ClassLoader to use for loading resources such
* as themes and messages (via {@link #getCurrentLoader}). If not set
* (e.g. is null), the current thread's context class loader will be
* used.
* @param customClassLoader The new class loader to use
*/
public static void setCustomClassLoader(ClassLoader customClassLoader) {
ClassLoaderFinder.customClassLoader = customClassLoader;
}
/**
* Return the best class loader to use for loading resources.
* This is normally the thread context class loader but can
* overridden using {@link #setCustomClassLoader}.
*
* @param fallbackClass If there is no context class loader, fall
* back to using the class loader for the given object
* @return A ClassLoader to use for loading resources
*/
public static ClassLoader getCurrentLoader(Object fallbackClass) {
ClassLoader loader = customClassLoader;
if (loader == null) {
loader = Thread.currentThread().getContextClassLoader();
}
if (loader == null) {
loader = fallbackClass.getClass().getClassLoader();
}
return loader;
}
}