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2010-06-01T05:04:29Z

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в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== AbstractSet Class ==



<source lang="java">
import java.io.Serializable;
import java.util.AbstractSet;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.Set;
class ArraySet extends AbstractSet implements Cloneable, Serializable {
private ArrayList list;
public ArraySet() {
list = new ArrayList();
}
public ArraySet(Collection col) {
list = new ArrayList();
Iterator itor = col.iterator();
if (col instanceof Set) {
while (itor.hasNext()) {
list.add(itor.next());
}
} else {
while (itor.hasNext()) {
add(itor.next());
}
}
}
public Iterator iterator() {
return list.iterator();
}
public int size() {
return list.size();
}
public boolean add(Object element) {
boolean modified;
if (modified = !list.contains(element)) {
list.add(element);
}
return modified;
}
public boolean remove(Object element) {
return list.remove(element);
}
public boolean isEmpty() {
return list.isEmpty();
}
public boolean contains(Object element) {
return list.contains(element);
}
public void clear() {
list.clear();
}
public Object clone() {
try {
ArraySet newSet = (ArraySet) super.clone();
newSet.list = (ArrayList) list.clone();
return newSet;
} catch (CloneNotSupportedException e) {
throw new InternalError();
}
}
}
public class MainClass {
public static void main(String args[]) {
String elements[] = { "A", "B", "C", "D", "E" };
Set set = new ArraySet(Arrays.asList(elements));
Iterator iter = set.iterator();
while (iter.hasNext()) {
System.out.println(iter.next());
}
}
}</source>



<pre class=codeResult>A
B
C
D
E</pre>

== One Item Set ==



<source lang="java">
/* $Id$
*
* Behavior Protocols Tools - Parsers, Transformations
* Copyright (C) 2006-2007 DSRG, Charles University in Prague
* http://dsrg.mff.cuni.cz/
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*
*/

import java.io.Serializable;
import java.util.AbstractCollection;
import java.util.Iterator;
import java.util.NoSuchElementException;

/**
*
* @author thorm
*/
public class OneItemSet<E> extends AbstractCollection<E> implements Serializable{

public boolean add(E i) {
if (item == i) {
return false;
}
if (item == null) {
item = i;
return true;
}
throw new IllegalArgumentException();
}

public Iterator<E> iterator() {
return new Iterator() {
public boolean hasNext() {
return hasNxt;
}

public E next() {
if (hasNxt) {
hasNxt = false;
return item;
}
throw new NoSuchElementException();
}

public void remove() {
item = null;
}
boolean hasNxt = true;
};
}

public int size() {
return (item == null) ? 0 : 1;
}
public int hashCode() {
return item.hashCode();
}
public boolean equals(Object o) {
return (o instanceof OneItemSet) && item.equals(((OneItemSet) o).item);
}

E item;
}</source>



== Things you can do with Sets ==



<source lang="java">
import java.util.Arrays;
import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;
public class MainClass {
static void fill(Set s) {
s.addAll(Arrays.asList("one two three four five six seven".split(" ")));
}
public static void test(Set s) {
System.out.println(s.getClass().getName().replaceAll("\\w+\\.", ""));
fill(s);
fill(s);
fill(s);
System.out.println(s); // No duplicates!
s.addAll(s);
s.add("one");
s.add("one");
s.add("one");
System.out.println(s);
System.out.println("s.contains(\"one\"): " + s.contains("one"));
}
public static void main(String[] args) {
test(new HashSet());
test(new TreeSet());
test(new LinkedHashSet());
}
}</source>



<pre class=codeResult>HashSet
[one, two, five, four, three, seven, six]
[one, two, five, four, three, seven, six]
s.contains("one"): true
TreeSet
[five, four, one, seven, six, three, two]
[five, four, one, seven, six, three, two]
s.contains("one"): true
LinkedHashSet
[one, two, three, four, five, six, seven]
[one, two, three, four, five, six, seven]
s.contains("one"): true</pre>

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Admin: 1 версия

в 17:44, 31 мая 2010