JAVAPRO<p>Mutable Schlüssel in <a href="https://mastodon.social/tags/HashMaps" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>HashMaps</span></a> können zu unsichtbaren Einträgen führen. Warum hashCode()-Änderungen fatale Folgen für Lookup, Security &amp; Konsistenz haben, zeigt <span class="h-card" translate="no"><a href="https://mastodon.social/@svenruppert" class="u-url mention" rel="nofollow noopener" target="_blank">@<span>svenruppert</span></a></span> in der interaktiven <a href="https://mastodon.social/tags/Vaadin" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Vaadin</span></a>-Demo. Teste es: <a href="https://javapro.io/de/wenn-hashcode-luegt-und-equals-hilflos-ist/" rel="nofollow noopener" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">javapro.io/de/wenn-hashcode-lu</span><span class="invisible">egt-und-equals-hilflos-ist/</span></a></p><p><a href="https://mastodon.social/tags/Vaadin" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Vaadin</span></a> <a href="https://mastodon.social/tags/Java" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>Java</span></a> <a href="https://mastodon.social/tags/JavaSecurity" class="mention hashtag" rel="nofollow noopener" target="_blank">#<span>JavaSecurity</span></a> @Vaadin</p>