001: // ============================================================================
002: // $Id: BitwiseOr.java,v 1.8 2006/08/07 04:02:50 davidahall Exp $
003: // Copyright (c) 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:
033: package net.sf.jga.fn.arithmetic;
034:
035: import java.text.MessageFormat;
036: import net.sf.jga.fn.BinaryFunctor;
037: import net.sf.jga.fn.EvaluationException;
038:
039: /**
040: * Binary Functor that returns the bitwise or of its two arguments
041: * <p>
042: * Copyright © 2005 David A. Hall
043: *
044: * @author <a href="mailto:davidahall@users.sourceforge.net">David A. Hall</a>
045: **/
046:
047: public class BitwiseOr<T extends Number> extends BinaryFunctor<T, T, T> {
048:
049: static final long serialVersionUID = -213586968622137607L;
050:
051: // Utility class that performs the math as appropriate for the class given at construction
052: transient private IntegerArithmetic<T> _math;
053:
054: // The type of operands this instance supports
055: private Class<T> _type;
056:
057: /**
058: * Builds BitwiseOr functor for the given class. The class argument must
059: * be the same as the generic class argument (when generics are in use)
060: * or else a ClassCastException will be thrown when the functor is used.
061: *
062: * @throws IllegalArgumentException if the given class has no Arithmetic
063: * implementation registered with the ArithmeticFactory
064: */
065: public BitwiseOr(Class<T> c) {
066: _type = c;
067: getMath();
068: }
069:
070: /**
071: * Returns the type of operands this instance supports
072: */
073: public Class<T> getType() {
074: return _type;
075: }
076:
077: // BinaryFunctor interface
078:
079: /**
080: * Given arguments <b>x</b> and <b>y</b>, x | y
081: * @return x | y
082: */
083: public T fn(T x, T y) {
084: try {
085: return getMath().or(x, y);
086: } catch (ClassCastException ex) {
087: String msg = "ClassCastException: Cannot compute {0}[{1}] | {2}[{3}]";
088: String err = MessageFormat.format(msg, new Object[] {
089: x.getClass(), x, y.getClass(), y });
090: throw new EvaluationException(err, ex);
091: }
092: }
093:
094: /**
095: * Calls the Visitor's <code>visit(BitwiseOr)</code> method, if it
096: * implements the nested Visitor interface.
097: */
098: public void accept(net.sf.jga.fn.Visitor v) {
099: if (v instanceof BitwiseOr.Visitor)
100: ((BitwiseOr.Visitor) v).visit(this );
101: else
102: v.visit(this );
103: }
104:
105: /**
106: */
107: private IntegerArithmetic<T> getMath() {
108: if (_math == null) {
109: _math = ArithmeticFactory.getIntegralArithmetic(_type);
110: if (_math == null) {
111: String msg = "No implementation of IntegerArithmetic registered for {0}";
112: throw new IllegalArgumentException(MessageFormat
113: .format(msg, new Object[] { _type }));
114: }
115: }
116:
117: return _math;
118: }
119:
120: // Object overrides
121:
122: public String toString() {
123: return "BitwiseOr";
124: }
125:
126: // AcyclicVisitor
127:
128: /**
129: * Interface for classes that may interpret a <b>BitwiseOr</b>
130: * functor.
131: */
132: public interface Visitor extends net.sf.jga.fn.Visitor {
133: public void visit(BitwiseOr host);
134: }
135:
136: }
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