в 17:43, 31 мая 2010

2010-05-31T17:43:48Z

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2010-05-31T14:12:02Z

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== Set: addAll(Collection c) ==



<source lang="java">

/*
Output:
true
false
* */
import java.util.HashSet;
import java.util.Set;
public class MainClass {
public static void main(String args[]) {
Set set = new HashSet();
Set set2 = new HashSet();
StringBuffer buff1 = new StringBuffer("Irish Setter");
StringBuffer buff2 = new StringBuffer("Irish Setter");
set.add(buff1);
set2.add(buff2);
System.out.println(set.addAll(set2));
System.out.println(set.addAll(set));
}
}

</source>



== Set: add(String e) ==



<source lang="java">

import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
Set<String> set = new HashSet<String>();
set.add("Hello");
if (set.add("Hello")) {
System.out.println("addition successful");
} else {
System.out.println("addition failed");
}
}
}

</source>



== Set: clear() ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
elements = new String[] { "E", "F" };
set.addAll(Arrays.asList(elements));
System.out.println(set);
set.clear();
System.out.println(set);
}
}

</source>



== Set: clone() ==



<source lang="java">

/*
Output:
[I, P, G, E]
[I, P, G, E]
* */
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class MainClass {
public static void main(String args[]) throws Exception {
String elements[] = { "I", "P", "E", "G", "P" };
Set set = new HashSet(Arrays.asList(elements));
Set set2 = ((Set) ((HashSet) set).clone());
System.out.println(set2);
FileOutputStream fos = new FileOutputStream("set.ser");
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(set);
oos.close();
FileInputStream fis = new FileInputStream("set.ser");
ObjectInputStream ois = new ObjectInputStream(fis);
Set set3 = (Set) ois.readObject();
ois.close();
System.out.println(set3);
}
}

</source>



== Set: containsAll(Collection<?> c) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
elements = new String[] { "A", "B", "C" };
Set<String> set2 = new HashSet<String>(Arrays.asList(elements));
System.out.println(set.containsAll(set2));
}
}

</source>



== Set: contains(Object o) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
System.out.println(set.contains("A"));
}
}

</source>



== Set: equals(Object o) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
elements = new String[] { "A", "B", "C", "D" };
Set<String> set2 = new HashSet<String>(Arrays.asList(elements));
System.out.println(set.equals(set2));
}
}

</source>



== Set: isEmpty() ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
System.out.println(set.isEmpty());
}
}

</source>



== Set: iterator() ==



<source lang="java">

/*
Output:
I
P
G
E
* */
import java.util.Arrays;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
public class MainClass {
public static void main(String args[]) {
String elements[] = { "I", "P", "E", "G", "P" };
Set set = new HashSet(Arrays.asList(elements));
Iterator iter = set.iterator();
while (iter.hasNext()) {
System.out.println(iter.next());
}
}
}

</source>



== Set: removeAll(Collection<?> c) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
elements = new String[] { "B", "D", "F", "G", "1", "2", "3", "4" };
Set<String> set2 = new HashSet<String>(Arrays.asList(elements));
set.removeAll(set2);
System.out.println(set);
}
}

</source>



== Set: remove(Object o) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
set.remove("A");
System.out.println(set);
}
}

</source>



== Set: retainAll(Collection c) ==



<source lang="java">

/*
--------------union--------------
A
B
C
--------------intersection--------------
A
B*/
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.TreeSet;
public class MainClass {
public static void main(String[] args) {
// Create two sets.
Set s1 = new HashSet();
s1.add("A");
s1.add("B");
s1.add("C");
Set s2 = new HashSet();
s2.add("A");
s2.add("B");
Set union = new TreeSet(s1);
union.addAll(s2); // now contains the union
print("union", union);
Set intersect = new TreeSet(s1);
intersect.retainAll(s2);
print("intersection", intersect);
}
protected static void print(String label, Collection c) {
System.out.println("--------------" + label + "--------------");
Iterator it = c.iterator();
while (it.hasNext()) {
System.out.println(it.next());
}
}
}

</source>



== Set: size() ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
System.out.println(set.size());
}
}

</source>



== Set: toArray() ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;
public class Main {
public static void main(String[] a) {
String elements[] = { "A", "B", "C", "D", "E" };
Set<String> set = new HashSet<String>(Arrays.asList(elements));
Object[] arrObj = set.toArray();
for (int i = 0; i < arrObj.length; i++) {
System.out.println(arrObj[i]);
}
System.out.println(set);
}
}

</source>



== Set: toArray(String[] a) ==



<source lang="java">

import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
public class Main {
public static void main(String[] args) {
// A string array with duplicate values
String[] data = { "A", "C", "B", "D", "A", "B", "E", "D", "B", "C" };
System.out.println("Original array : " + Arrays.toString(data));
List<String> list = Arrays.asList(data);
Set<String> set = new HashSet<String>(list);
System.out.print("Remove duplicate result: ");
String[] result = new String[set.size()];
set.toArray(result);
for (String s : result) {
System.out.print(s + ", ");
}
}
}

</source>

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