01: /*
02: * <copyright>
03: *
04: * Copyright 1997-2007 BBNT Solutions, LLC
05: * under sponsorship of the Defense Advanced Research Projects
06: * Agency (DARPA).
07: *
08: * You can redistribute this software and/or modify it under the
09: * terms of the Cougaar Open Source License as published on the
10: * Cougaar Open Source Website (www.cougaar.org).
11: *
12: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
13: * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
14: * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
15: * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
16: * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
17: * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
18: * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
22: * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23: *
24: * </copyright>
25: */
26:
27: package org.cougaar.core.util;
28:
29: /**
30: * A proxy class for a strongly reachable object, similar to the reference
31: * types in <code>java.lang.ref</code>.
32: * <p>
33: * This class is simply used for objects that can be GC'ed when the client
34: * is done processing the referent. It's like a SoftReference, which is
35: * clearly marked and can be passed around in unmodifable collections, except
36: * that we want to control when it can be GC'ed.
37: * <p>
38: * Ideally this class would be in java/lang/ref and would extend Reference,
39: * if only for symmetry.
40: */
41: public final class StrongReference {
42: private Object referent;
43:
44: public StrongReference(Object referent) {
45: this .referent = referent;
46: }
47:
48: public Object get() {
49: return referent;
50: }
51:
52: public void clear() {
53: referent = null;
54: }
55: }
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