El método contains(E e) de CopyOnWriteArraySet comprueba si un elemento dado está presente en el Conjunto o no.
Sintaxis:
public boolean contains(Object o)
Parámetros: La función acepta un único parámetro obligatorio que especifica el elemento cuya apariencia se desea comprobar en el Conjunto.
Valor devuelto: la función devuelve verdadero si el elemento está presente; de lo contrario, devuelve falso.
Los siguientes programas ilustran la función anterior:
Programa 1:
// Java Program to illustrate the CopyOnWriteArraySet
// contains() method in Java
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create object of CopyOnWriteArraySet
CopyOnWriteArraySet<Integer> ArrSet
= new CopyOnWriteArraySet<Integer>();
// Add elements
ArrSet.add(32);
ArrSet.add(67);
ArrSet.add(67);
ArrSet.add(100);
// print CopyOnWriteArraySet
System.out.println("CopyOnWriteArraySet: "
+ ArrSet);
// check if 100 is present
// using contains() function
if (ArrSet.contains(100))
System.out.println("100 is "
+ "present in the Set");
else
System.out.println("100 is "
+ "not present in the Set");
// check if 20 is present
// using contains() function
if (ArrSet.contains(20))
System.out.println("20 is "
+ "present in the Set");
else
System.out.println("20 is "
+ "not present in the Set");
}
}
Producción:
CopyOnWriteArraySet: [32, 67, 100] 100 is present in the Set 20 is not present in the Set
Programa 2:
// Java Program to illustrate the CopyOnWriteArraySet
// contains() method in Java
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// create object of CopyOnWriteArraySet
CopyOnWriteArraySet<String> ArrSet
= new CopyOnWriteArraySet<String>();
// Add elements
ArrSet.add("geeks");
ArrSet.add("gfg");
ArrSet.add("jgec");
ArrSet.add("sudo");
// print CopyOnWriteArraySet
System.out.println("CopyOnWriteArraySet: "
+ ArrSet);
// check using contains() function
if (ArrSet.contains("gfg"))
System.out.println("gfg is "
+ "present in the Set");
else
System.out.println("gfg is "
+ "not present in the Set");
// check using contains() function
if (ArrSet.contains("best"))
System.out.println("best is "
+ "present in the Set");
else
System.out.println("best is "
+ "not present in the Set");
}
}
Producción:
CopyOnWriteArraySet: [geeks, gfg, jgec, sudo] gfg is present in the Set best is not present in the Set