Java Tutorial/Collections/LinkedHashSet

Get Size of Java LinkedHashSet

   <source lang="java">

import java.util.LinkedHashSet; public class Main {

 public static void main(String[] args) {
   LinkedHashSet<Integer> lhashSet = new LinkedHashSet<Integer>();
   System.out.println("Size of LinkedHashSet : " + lhashSet.size());
   lhashSet.add(new Integer("1"));
   lhashSet.add(new Integer("2"));
   lhashSet.add(new Integer("3"));
   System.out.println(lhashSet.size());
   lhashSet.remove(new Integer("1"));
   System.out.println(lhashSet.size());
 }

}</source>

Iterate through elements of Java LinkedHashSet

   <source lang="java">

import java.util.Iterator; import java.util.LinkedHashSet; public class Main {

 public static void main(String[] args) {
   LinkedHashSet<Integer> lhashSet = new LinkedHashSet<Integer>();
   lhashSet.add(new Integer("1"));
   lhashSet.add(new Integer("2"));
   lhashSet.add(new Integer("3"));
   Iterator itr = lhashSet.iterator();
   while (itr.hasNext()){
     System.out.println(itr.next());
   }
 }

}</source>

Putting your own type in a LinkedHashSet

   <source lang="java">

import java.util.LinkedHashSet; import java.util.Set; public class MainClass {

 public static Set fill(Set a, int size) {
   for (int i = 0; i < size; i++)
     a.add(new MyType(i));
   return a;
 }
 public static void test(Set a) {
   fill(a, 10);
   fill(a, 10); // Try to add duplicates
   fill(a, 10);
   System.out.println(a);
 }
 public static void main(String[] args) {
   test(new LinkedHashSet());
 }

} class MyType implements Comparable {

 private int i;
 public MyType(int n) {
   i = n;
 }
 public boolean equals(Object o) {
   return (o instanceof MyType) && (i == ((MyType) o).i);
 }
 public int hashCode() {
   return i;
 }
 public String toString() {
   return i + " ";
 }
 public int compareTo(Object o) {
   int i2 = ((MyType) o).i;
   return (i2 < i ? -1 : (i2 == i ? 0 : 1));
 }

} //</source>

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Remove all elements from Java LinkedHashSet

   <source lang="java">

import java.util.LinkedHashSet; public class Main {

 public static void main(String[] args) {
   LinkedHashSet<Integer> lhashSet = new LinkedHashSet<Integer>();
   lhashSet.add(new Integer("1"));
   lhashSet.add(new Integer("2"));
   lhashSet.add(new Integer("3"));
   System.out.println(lhashSet);
   lhashSet.clear();
   System.out.println(lhashSet);
   System.out.println(lhashSet.isEmpty());
 }

}</source>

Remove specified element from Java LinkedHashSet

   <source lang="java">

import java.util.LinkedHashSet; public class Main {

 public static void main(String[] args) {
   LinkedHashSet<Integer> lhashSet = new LinkedHashSet<Integer>();
   
   lhashSet.add(new Integer("1"));
   lhashSet.add(new Integer("2"));
   lhashSet.add(new Integer("3"));
   System.out.println(lhashSet);
   boolean blnRemoved = lhashSet.remove(new Integer("2"));
   System.out.println(blnRemoved);
   System.out.println(lhashSet);
 }

}</source>