package com.example;

import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.*;

public class MainTest {

    @Test
    @DisplayName("Basic navigation: visit, back, forward")
    void testBasicNavigation() {
        BrowserHistory bh = new BrowserHistory("leetcode.com");
        bh.visit("google.com");
        bh.visit("facebook.com");
        bh.visit("youtube.com");
        assertEquals("facebook.com", bh.back(1), "Should go back to facebook.com");
        assertEquals("google.com", bh.back(1), "Should go back to google.com");
        assertEquals("facebook.com", bh.forward(1), "Should go forward to facebook.com");
        bh.visit("linkedin.com");
        assertEquals("linkedin.com", bh.getCurrentPage(), "Should be linkedin.com after visit");
        assertEquals("google.com", bh.back(2), "Should go back to google.com");
        assertEquals("leetcode.com", bh.back(2), "Should go back to leetcode.com (can't go further)");
        assertEquals("google.com", bh.forward(1), "Should go forward to google.com (can't go further than available)");
    }

    @Test
    @DisplayName("Back and forward at boundaries")
    void testBoundaries() {
        BrowserHistory bh = new BrowserHistory("start.com");
        assertEquals("start.com", bh.back(1), "Back at homepage should stay at homepage");
        assertEquals("start.com", bh.forward(1), "Forward at homepage should stay at homepage");
        bh.visit("a.com");
        bh.visit("b.com");
        bh.visit("c.com");
        assertEquals("a.com", bh.back(2), "Should go back to a.com");
        assertEquals("start.com", bh.back(10), "Back more steps than history should stay at homepage");
        assertEquals("a.com", bh.forward(1), "Should go forward to a.com");
        assertEquals("c.com", bh.forward(10), "Forward more steps than possible should go to last visited");
    }

    @Test
    @DisplayName("Forward stack clears on visit")
    void testForwardStackClearsOnVisit() {
        BrowserHistory bh = new BrowserHistory("home.com");
        bh.visit("1.com");
        bh.visit("2.com");
        bh.back(1);
        bh.visit("3.com");
        assertEquals("home.com", bh.back(2), "Should go back to home.com");
        assertEquals("1.com", bh.forward(1), "Should go forward to 1.com");
        assertEquals("3.com", bh.forward(2), "Should go forward to 3.com (can't go past)");
    }

    @Test
    @DisplayName("Get current page after operations")
    void testGetCurrentPage() {
        BrowserHistory bh = new BrowserHistory("main.com");
        assertEquals("main.com", bh.getCurrentPage(), "Initial page should be main.com");
        bh.visit("a.com");
        bh.visit("b.com");
        bh.back(1);
        assertEquals("a.com", bh.getCurrentPage(), "After back, should be a.com");
        bh.forward(1);
        assertEquals("b.com", bh.getCurrentPage(), "After forward, should be b.com");
    }
}

MainTest.java

Käytännön opas Javan tietorakenteisiin ja kokoelmiin. Tutustu listoihin, linkitettyihin listoihin, jonoihin, dequeihin, pinoihin ja mappeihin harjoittelemalla CRUD-toimintoja, algoritmien monimutkaisuutta sekä käytännön haasteita, kuten kirjastonhallintaa ja selaimen historiaa.

Käytännön opas Javan tietorakenteisiin ja kokoelmiin. Sisältää listat, linkitetyt listat, jonot, kaksipäiset jonot, pinot ja hajautustaulut sekä CRUD-toiminnot, algoritminen kompleksisuus ja käytännön haasteet, kuten kirjastonhallinta ja selaimen historia.

Haaste: Selaushistorian Toteuttaminen

Ratkaisu