com.sun.xml.ws.developer.ContextClassloaderLocal Maven / Gradle / Ivy
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package com.sun.xml.ws.developer;
import com.sun.xml.ws.resources.ContextClassloaderLocalMessages;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.WeakHashMap;
/**
* Simple utility ensuring that the value is cached only in case it is non-internal implementation
*/
abstract class ContextClassloaderLocal {
private WeakHashMap CACHE = new WeakHashMap<>();
public V get() throws Error {
ClassLoader tccl = getContextClassLoader();
V instance = CACHE.get(tccl);
if (instance == null) {
instance = createNewInstance();
CACHE.put(tccl, instance);
}
return instance;
}
public void set(V instance) {
CACHE.put(getContextClassLoader(), instance);
}
protected abstract V initialValue() throws Exception;
private V createNewInstance() {
try {
return initialValue();
} catch (Exception e) {
throw new Error(ContextClassloaderLocalMessages.FAILED_TO_CREATE_NEW_INSTANCE(getClass().getName()), e);
}
}
private static ClassLoader getContextClassLoader() {
return AccessController.doPrivileged(new PrivilegedAction() {
@Override
public ClassLoader run() {
ClassLoader cl = null;
try {
cl = Thread.currentThread().getContextClassLoader();
} catch (SecurityException ex) {
}
return cl;
}
});
}
}