Java example source code file (AReference.java)

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Java - Java tags/keywords

areference, cons, ipersistentmap, ireference, iseq

The AReference.java Java example source code

/**
 *   Copyright (c) Rich Hickey. All rights reserved.
 *   The use and distribution terms for this software are covered by the
 *   Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
 *   which can be found in the file epl-v10.html at the root of this distribution.
 *   By using this software in any fashion, you are agreeing to be bound by
 * 	 the terms of this license.
 *   You must not remove this notice, or any other, from this software.
 **/

/* rich Dec 31, 2008 */

package clojure.lang;

public class AReference implements IReference {
    private IPersistentMap _meta;

    public AReference() {
        this(null);
    }

    public AReference(IPersistentMap meta) {
        _meta = meta;
    }

    synchronized public IPersistentMap meta() {
        return _meta;
    }

    synchronized public IPersistentMap alterMeta(IFn alter, ISeq args)  {
        _meta = (IPersistentMap) alter.applyTo(new Cons(_meta, args));
        return _meta;
    }

    synchronized public IPersistentMap resetMeta(IPersistentMap m) {
        _meta = m;
        return m;
    }

}