001: /*--
002:
003: Copyright (C) 2002-2005 Adrian Price.
004: All rights reserved.
005:
006: Redistribution and use in source and binary forms, with or without
007: modification, are permitted provided that the following conditions
008: are met:
009:
010: 1. Redistributions of source code must retain the above copyright
011: notice, this list of conditions, and the following disclaimer.
012:
013: 2. Redistributions in binary form must reproduce the above copyright
014: notice, this list of conditions, and the disclaimer that follows
015: these conditions in the documentation and/or other materials
016: provided with the distribution.
017:
018: 3. The names "OBE" and "Open Business Engine" must not be used to
019: endorse or promote products derived from this software without prior
020: written permission. For written permission, please contact
021: adrianprice@sourceforge.net.
022:
023: 4. Products derived from this software may not be called "OBE" or
024: "Open Business Engine", nor may "OBE" or "Open Business Engine"
025: appear in their name, without prior written permission from
026: Adrian Price (adrianprice@users.sourceforge.net).
027:
028: THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
029: WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
030: OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
031: DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
032: INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
033: (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
034: SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
035: HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
036: STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
037: IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
038: POSSIBILITY OF SUCH DAMAGE.
039:
040: For more information on OBE, please see
041: <http://obe.sourceforge.net/>.
042:
043: */
044:
045: package org.obe.util;
046:
047: import java.io.InvalidObjectException;
048: import java.io.ObjectStreamException;
049: import java.util.Arrays;
050: import java.util.Collections;
051: import java.util.List;
052: import java.util.Map;
053:
054: /**
055: * An abstract base implementation for enumerated types. This class is very
056: * similar to the primordial generic Enum class described by JDK 1.5:
057: * <p/>
058: * <code>public abstract class Enum <T extends Enum<T>><br/>
059: * implements Comparable<T>, Serializable<code>
060: *
061: * @author Adrian Price
062: */
063: public abstract class AbstractEnum implements Enum {
064: private static final long serialVersionUID = -8760826706749553497L;
065: public final String name;
066: public final int ordinal;
067:
068: /**
069: * Used by subclasses to initialize their static list and map fields.
070: *
071: * @param values The complete set of enum values.
072: * @param tagMap The map-by-name to initialize.
073: * @return An unmodifiable list of enumerated values, in declaration order.
074: */
075: protected static List clinit(AbstractEnum[] values, Map tagMap) {
076: for (int i = 0; i < values.length; i++)
077: tagMap.put(values[i].name, values[i]);
078: return Collections.unmodifiableList(Arrays.asList(values));
079: }
080:
081: protected AbstractEnum(String name, int ordinal) {
082: this .ordinal = ordinal;
083: this .name = name;
084: }
085:
086: protected final Object clone() throws CloneNotSupportedException {
087: throw new CloneNotSupportedException();
088: }
089:
090: public final int compareTo(Object o) {
091: if (o != null && getClass() != o.getClass()) {
092: throw new IllegalArgumentException(getClass().getName()
093: + " cannot be compared to " + o.getClass());
094: }
095: // (null sorts to the top)
096: return o == null ? -1 : ordinal - ((AbstractEnum) o).ordinal;
097: }
098:
099: public final boolean equals(Object obj) {
100: return this == obj;
101: }
102:
103: public final int hashCode() {
104: return ordinal;
105: }
106:
107: protected final Object readResolve() throws ObjectStreamException {
108: try {
109: return family().get(ordinal);
110: } catch (Exception e) {
111: throw new InvalidObjectException(String.valueOf(ordinal));
112: }
113: }
114:
115: public final String toString() {
116: return name;
117: }
118:
119: public final int value() {
120: return ordinal;
121: }
122: }
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