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This module contains the Metro runtime code.
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/*
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 *
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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
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package com.sun.xml.ws.spi;

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;
            }
        });
    }
}