001: // ============================================================================
002: // $Id: Find.java,v 1.17 2006/12/05 04:52:38 davidahall Exp $
003: // Copyright (c) 2003-2005 David A. Hall
004: // ============================================================================
005: // The contents of this file are subject to the Common Development and
006: // Distribution License (CDDL), Version 1.0 (the License); you may not use this
007: // file except in compliance with the License. You should have received a copy
008: // of the the License along with this file: if not, a copy of the License is
009: // available from Sun Microsystems, Inc.
010: //
011: // http://www.sun.com/cddl/cddl.html
012: //
013: // From time to time, the license steward (initially Sun Microsystems, Inc.) may
014: // publish revised and/or new versions of the License. You may not use,
015: // distribute, or otherwise make this file available under subsequent versions
016: // of the License.
017: //
018: // Alternatively, the contents of this file may be used under the terms of the
019: // GNU Lesser General Public License Version 2.1 or later (the "LGPL"), in which
020: // case the provisions of the LGPL are applicable instead of those above. If you
021: // wish to allow use of your version of this file only under the terms of the
022: // LGPL, and not to allow others to use your version of this file under the
023: // terms of the CDDL, indicate your decision by deleting the provisions above
024: // and replace them with the notice and other provisions required by the LGPL.
025: // If you do not delete the provisions above, a recipient may use your version
026: // of this file under the terms of either the CDDL or the LGPL.
027: //
028: // This library is distributed in the hope that it will be useful,
029: // but WITHOUT ANY WARRANTY; without even the implied warranty of
030: // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
031: // ============================================================================
032: package net.sf.jga.fn.algorithm;
033:
034: import java.util.Iterator;
035: import net.sf.jga.fn.UnaryFunctor;
036: import net.sf.jga.fn.comparison.EqualTo;
037: import net.sf.jga.fn.comparison.Equality;
038: import net.sf.jga.util.FindIterator;
039:
040: /**
041: * Locates values in an iteration.
042: * <p>
043: * Copyright © 2003-2005 David A. Hall
044: *
045: * @author <a href="mailto:davidahall@users.sf.net">David A. Hall</a>
046: * @deprecated
047: */
048:
049: public class Find<T> extends FindIteratorFunctor<T> {
050:
051: static final long serialVersionUID = -556722539704270804L;
052:
053: // the functor used to determine if an element is the one being searched for
054: private UnaryFunctor<T, Boolean> _eq;
055:
056: /**
057: * Builds a Find functor that looks for the given value, using the value's
058: * equals() method.
059: */
060: public Find(T value) {
061: this (new EqualTo<T>().bind2nd(value));
062: }
063:
064: /**
065: * Builds a Find functor that looks for the given value, using the given
066: * Equality predicate.
067: */
068: public Find(Equality<T> eq, T value) {
069: this (eq.bind2nd(value));
070: }
071:
072: /**
073: * Builds a Find functor that looks for values for which the given predicate
074: * returns TRUE.
075: */
076: public Find(UnaryFunctor<T, Boolean> eq) {
077: _eq = eq;
078: }
079:
080: /**
081: * Returns the functor used to determine if an element is the one being
082: * searched for.
083: */
084: public UnaryFunctor<T, Boolean> getComparisonFn() {
085: return _eq;
086: }
087:
088: /**
089: * Locates the first/next element that meets the given criteria.
090: * @return an Iterator whose next() [if it hasNext()] will return an
091: * element that meets the given criteria. If no such element exists, then
092: * the returned iterator's hasNext() is false.
093: */
094: public FindIterator<T> fn(Iterator<? extends T> iterator) {
095: FindIterator<T> finder = wrap(iterator);
096: finder.findNext(_eq);
097: return finder;
098: }
099:
100: /**
101: * Calls the Visitor's <code>visit(Find)</code> method, if it
102: * implements the nested Visitor interface.
103: */
104: public void accept(net.sf.jga.fn.Visitor v) {
105: if (v instanceof Find.Visitor)
106: ((Find.Visitor) v).visit(this );
107: else
108: v.visit(this );
109: }
110:
111: // Object overrides
112:
113: public String toString() {
114: return "Find[" + _eq + "]";
115: }
116:
117: // AcyclicVisitor
118:
119: /**
120: * Interface for classes that may interpret an <b>Find</b> functor.
121: */
122: public interface Visitor extends net.sf.jga.fn.Visitor {
123: public void visit(Find host);
124: }
125: }
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