CodeGym
AI Academy
Promotion
CodeGym University
Learning
Courses
Tasks
Surveys & Quizzes
Games
Help
Schedule
Community
Users
Forum
Chat
Articles
Success stories
Activity
Reviews
Subscriptions
Light theme

Tasks

  • Reviews
  • About us
Start
Start learning
Start learning now
  • All tasks
  • CRM Clients: Ensuring Data Integrity on Load

    JAVA 25 SELF
    Level 43, Lesson 4
    CRM Clients: Ensuring Data Integrity on Load
    1
    Locked
  • Digital Personal Records Registry 🏢

    JAVA 25 SELF
    Level 44, Lesson 0
    Digital Personal Records Registry 🏢
    1
    Locked
  • Managing complex delivery logistics: deeply nested data 🌍

    JAVA 25 SELF
    Level 44, Lesson 0
    Managing complex delivery logistics: deeply nested data 🌍
    1
    Locked
  • Mapping underground tunnels with a cyclic route 🚇

    JAVA 25 SELF
    Level 44, Lesson 1
    Mapping underground tunnels with a cyclic route 🚇
    1
    Locked
  • Managing a Hypermarket Catalog: Product Hierarchy and Collections 🏪

    JAVA 25 SELF
    Level 44, Lesson 1
    Managing a Hypermarket Catalog: Product Hierarchy and Collections 🏪
    1
    Locked
  • Paradoxical list: a collection that contains itself 🤯

    JAVA 25 SELF
    Level 44, Lesson 2
    Paradoxical list: a collection that contains itself 🤯
    1
    Locked
  • Saving Network Topology: Serializing a Graph with a Cyclic Route 🌐

    JAVA 25 SELF
    Level 44, Lesson 2
    Saving Network Topology: Serializing a Graph with a Cyclic Route 🌐
    1
    Locked
  • Collaborative work with a shared document: preserving shared objects 📝

    JAVA 25 SELF
    Level 44, Lesson 3
    Collaborative work with a shared document: preserving shared objects 📝
    1
    Locked
  • Inventory management: object identity with separate storage 📦

    JAVA 25 SELF
    Level 44, Lesson 3
    Inventory management: object identity with separate storage 📦
    1
    Locked
  • Incorrect data interpretation: `ClassCastException` after deserialization 🚨

    JAVA 25 SELF
    Level 44, Lesson 4
    Incorrect data interpretation: `ClassCastException` after deserialization 🚨
    1
    Locked
  • Digital Archivist: Efficient Storage of Large Data Sets with Compression 🗄️

    JAVA 25 SELF
    Level 44, Lesson 4
    Digital Archivist: Efficient Storage of Large Data Sets with Compression 🗄️
    1
    Locked
  • Non-serializable field for a game session

    JAVA 25 SELF
    Level 45, Lesson 0
    Non-serializable field for a game session
    1
    Locked
  • 1
  • ...
  • 54
  • 55
  • 56
  • 57
  • 58
  • ...
  • 74
Learn
  • Registration
  • Java Course
  • Help with Tasks
  • Pricing
  • Java Syntax
Community
  • Users
  • Articles
  • Forum
  • Chat
  • Success Stories
  • Activity
  • Affiliate Program
Company
  • About us
  • Contacts
  • Reviews
  • Press Room
  • CodeGym for EDU
  • FAQ
  • Support
CodeGym CodeGym is an online course for learning Java programming from scratch. This course is a perfect way to master Java for beginners. It contains 1200+ tasks with instant verification and an essential scope of Java fundamentals theory. To help you succeed in education, we’ve implemented a set of motivational features: quizzes, coding projects, content about efficient learning, and a Java developer’s career.
Follow us
Interface language
English
Deutsch Español हिन्दी Français Português Polski বাংলা 简体中文 मराठी தமிழ் Italiano Bahasa Indonesia 繁體中文 Nederlands 日本語 한국어 Bulgarian Danish Hungarian Basa Jawa Malay Norwegian Romanian Swedish Telugu Thai Українська Filipino Turkish Azərbaycan Русский Vietnamese
Programmers Are Made, Not Born © 2026 CodeGym
MastercardVisa
Programmers Are Made, Not Born © 2026 CodeGym