HashSet in java
HashSet used to store the data and Its remove Duplicate data.The data stored in Hashtable.
Add
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
num.add(1);
System.out.print(num);
}
}
Output
[1, 2, 3]
Contains
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
System.out.print(num.contains(1));
}
}
Output
true
Remove
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
num.remove(1);
System.out.print(num);
}
}
Output
[2, 3]
Size
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
System.out.print(num.size());
}
}
Output
3
Clear
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
num.clear();
System.out.print(num);
}
}
Output
[]
print each element:
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<Integer> num = new HashSet<Integer>();
num.add(1);
num.add(2);
num.add(3);
for(int i : num)
{
System.out.println(i);
}
}
}
Output
1 2 3
String:
Add
import java.util.HashSet;
public class Main
{
public static void main(String[] args)
{
HashSet<String> names = new HashSet<String>();
names.add("jack");
names.add("stark");
names.add("steve");
System.out.println(names);
}
}
Output
[stark, steve, jack]