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All quests Java Syntax Java Core Java Multithreading Java Collections JSP & Servlets Module 3. Java Professional Module 4. SQL & Hibernate Module 5. Spring Spring
All levels Level 0 Level 1 Level 2 Level 3 Level 4 Level 5 Level 6 Level 7 Level 8 Level 9 Level 10 Level 11 Level 12 Level 13 Level 14 Level 15 Level 16 Level 17 Level 18 Level 19 Level 20 Level 21 Level 22 Level 23 Level 24 Level 25 Level 26 Level 27 Level 28
  • You've reached Level 37

    Java Collections
    Level 7, Lesson 0
    You've reached Level 37
    Available
  • Design patterns: singleton, factory, factory method, abstract factory

    Java Collections
    Level 7, Lesson 1
    "Hi, Amigo!" "Hi, Bilaabo!" "Our topic today won't merely be interesting — it will be downright epic." "Today I'm going to you what design patterns are." "Cool! I've heard a lot about them. I can't wait!" "Experienced programmers have to write a lot of classes. But the most difficult part of this job is deciding which classes to create and how to divide the work among them ..."
    Available
  • Patterns: Adapter, Proxy, Bridge

    Java Collections
    Level 7, Lesson 2
    "Hello, friend!" "Hi, Bilaabo!" "We still have some time left, so I'll tell you about three more patterns." "Three more? How many are there in all?" "There are currently dozens of popular patterns, but the number of «successful solutions» is unlimited." "I see. So I have to learn several dozen patterns? ..."
    Available
  • Iterators

    Java Collections
    Level 7, Lesson 3
    "Hi, Amigo!" "Hi, Ellie!" "Today I want to tell you about iterators." "Iterators were invented practically at the same time as collections. The main purpose of collections is to store elements, and the main purpose of an iterator is to retrieve these elements one by one." "What's so difficult about getting a set of elements?" "First, the elements in some collections, such as Set, don't have ..."
    Available
  • Tasks | Level 7 | Lesson 4

    Java Collections
    Level 7, Lesson 4
    "Hi, buddy. Here's an interesting task for you." "Wait, I'm getting a call" "Hello? Uh-huh... Yes... Factory... What about this factory??? Hello? Hello?" "Amigo, the captain called and said something about some factory and a secret agent. You're my friend, right? Go to this Agent IntelliJ IDEA and find out what's up with the factory. But, shh! Don't tell anyone." "Yes, I know the secret agent ..."
    Available
  • Map hierarchy

    Java Collections
    Level 7, Lesson 5
    "And at long last, I'll tell you about Map." "Map, as you know, stores a set of key-value pairs. The keys must be unique, but the values can be anything. If you add a key-value pair to a Map, and the collection already contains the key, then the old value will be replaced with the new one. In other words, the key acts like a special index that can be any object. ..."
    Available
  • Tasks | Level 7 | Lesson 6

    Java Collections
    Level 7, Lesson 6
    Available
  • Arrays

    Java Collections
    Level 7, Lesson 7
    "Hi, Amigo!" "How was your morning lesson?" "Well, it was decent. I'll tell you about it." "Bilaabo gave me a bunch of design patterns, and Ellie showed me a whole bunch of collections. Not an easy day after all." "Don't you worry — I won't burden you with very much." "I want to tell you about the two utility classes that you've already encountered." "The Arrays and Collections classes ..."
    Available
  • Tasks | Level 7 | Lesson 8

    Java Collections
    Level 7, Lesson 8
    "Amigo, I'm now only going to give you one task — but it's a very cool task! You've never done one like this before. It represents the pinnacle of skill! Now where is it... uh ... hmm... Anyway, go and do the tasks that you haven't done yet. Rest up and come again. I'll find it for you ..."
    Available
  • Collections

    Java Collections
    Level 7, Lesson 9
    "Here I am." "I've been waiting for you here for a long time." "I hope so. Let's carry on, then." "I'm going to introduce you to present you a super-duper full-featured utility class for collections." "I'm already shaking all over with excitement." "Great. Then let's get started. Here are the methods of the Collections class ..."
    Available
  • Tasks | Level 7 | Lesson 10

    Java Collections
    Level 7, Lesson 10
    "Hi, Amigo. Here's a useful task." "I remembered! Here's the task I promised you last time. Do you know what a SET is?" "I've know for a long time. And Rishi just told me about Collections utility class." "SET stands for Super Extreme Task. What did Rishi tell you about it?" "Uh, he told me about something else... about useful methods for collections." "About something else?? Okay, go check the task conditions ..."
    Available
  • Learning to google | Level 7 | Lesson 11

    Java Collections
    Level 7, Lesson 11
    "Hi, Amigo!" "Let's continue our lessons on how to google." "Here are some exercises ..."
    Available
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