HashSet ngandhut () Metode ing Jawa

Apa HashSet?

HashSet minangka jinis data sing dibangun ing Jawa, lan kanthi istilah awam sampeyan bisa ngomong "HashSet minangka koleksi unsur unik sing ora diurutake." Deleng conto dhasar: Gambar 1: Ilustrasi sing nuduhake conto HashSet sing bener lan ora bener (Sadurunge sampeyan nerusake luwih, kita ngarepake sampeyan ngerti babagan istilah hashing lan tabel hash .) HashSet ngluwihi ( ndawakake tegese kelas diwarisake saka kelas liyane) AbstractSet lan ngleksanakake antarmuka Set. Ing ngisor iki sawetara poin sing kudu ditimbang sadurunge nggarap HashSets:

• Iku nggawe koleksi ( koleksi tegese unit siji saka obyek contone: ArrayList, LinkedList, Vector etc) sing nggunakake tabel hash kanggo panyimpenan.
• Nilai duplikat ora diidini ing HashSet.
• Sampeyan bisa nglebokake nilai "null" ing HashSet.
• Ora urutan selipan maintained. Dadi yen sampeyan pengin nglebokake item kanthi urut, HashSet bakal dadi pilihan sing ora becik kanggo kabutuhan sampeyan.
• Yen sampeyan pengin njaluk / njupuk unsur ing wektu pancet (O (1)) banjur HashSet iku salah siji saka pendekatan paling sampeyan bisa njupuk.

Apa metode HashSet.contains()?

HashSet.contains () minangka cara boolean kanggo mriksa yen ana item ing conto HashSet utawa ora. Cukup, manawa set kasebut ngemot unsur sing dikarepake. Java.util.HashSet nyedhiyakake implementasine sing efisien. Ayo kita nuduhake sampeyan carane sampeyan bisa nggunakake kanthi efektif kanggo ngatasi pitakon sampeyan.

ngandhut () karo Integers

import java.util.HashSet;

public class HashSetDemo {
   public static void main(String[] args) {

       // Declare your hash set
       HashSet digits = new HashSet();

       digits.add(0);
       digits.add(1);
       digits.add(2);
       digits.add(3);
       digits.add(4);
       digits.add(5);
       digits.add(null);
       System.out.println("All elements in hashset:\t" + digits);

       // Try adding duplicates
       digits.add(5);
       digits.add(2);
       System.out.println("After adding duplicates: \t" + digits);

       System.out.println("\n-------Using Contains Method-------");
       // Check out if the following digits exist in the hashset
       System.out.println("digits.contains(0) : " + digits.contains(0));
       System.out.println("digits.contains(2) : " + digits.contains(2));
       System.out.println("digits.contains(3) : " + digits.contains(7));
       System.out.println("digits.contains(null) : " + digits.contains(null));
   }
}

Output

ngandhut () karo Strings

Deleng conto liyane ngemot () metode karo Strings .

import java.util.HashSet;
public class HashSetDemo {
     public static void main(String[] args) {

	  // Try working with another hash set of String type
	  HashSet rainbow = new HashSet();

        // Adding elements into HashSet using add()
        rainbow.add("Red");
        rainbow.add("Orange");
        rainbow.add("Yellow");
        rainbow.add("Green");
        rainbow.add("Blue");
        rainbow.add("Indigo");
        rainbow.add("Violet");


        // Let's traverse the hashset
        System.out.println("Traversing the rainbow:");
        for (String i : rainbow){
             System.out.println(i);
        }
       // Check out if rainbow contains this color or not
    	 System.out.println("\n-------Using Contains Method-------");

        System.out.println("rainbow.contains(\"Yellow\"): \t" + rainbow.contains("Yellow"));
        System.out.println("rainbow.contains(\"White\"): \t"  + rainbow.contains("White"));
        System.out.println("rainbow.contains(\"Lavender\"): \t"  + rainbow.contains("Lavender"));
        System.out.println("rainbow.contains(\"Red\"): \t"  + rainbow.contains("Red"));

        // Remove a color from rainbow using remove()
        rainbow.remove("Red");

        // Now consume  set contains() method again to check if it's still present
        System.out.println("rainbow.contains(\"Red\"): \t"  + rainbow.contains("Red"));

        System.out.println("\nAfter removing Red: " + rainbow);
	}
}

Output Nalika sampeyan bisa ndeleng urutan output beda saka urutan panggolekan unsur menyang Hashset.

Kesimpulan

Cara ngandhut () kanggo HashSets iku cukup prasaja kanggo nggunakake. Nanging, yen ana kebingungan, sampeyan bisa tansah ngrujuk menyang kiriman iki. Sugeng Coding! :)