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Summary - Advanced coroutines

Combine CoroutineScope, Dispatchers and Job to write a parallel job manager.

Summary - Advanced coroutines

This group covered CoroutineScope, Dispatchers, Job, SupervisorJob and CoroutineExceptionHandler. Their common thread: each manages some part of a coroutine's lifecycle and environment.

The next lesson has a mini task that brings these pieces together. Scope sets the boundary, dispatcher the thread, Job the waiting, SupervisorJob the isolation and the handler the error path. Together they form robust concurrent code.

Practice Combine all pieces

Open runBlocking. Write val job = launch { println("Started") }. Wait with job.join(). Then print println("Done").

Starter code

Main.kt
// Summary: runBlocking, launch, join
// write here
fun main() {
    
}

Sample solution

Main.kt
fun main() = runBlocking {
    val job = launch {
        println("Started")
    }
    job.join()
    println("Done")
}

Expected output

Started
Done

Questions and answers

Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.

1 Which one relates to SupervisorJob?

  • Dispatchers.IO
  • Isolates child failures Correct answer
  • runBlocking
  • launch

Explanation: SupervisorJob keeps one child's failure from spreading to siblings.

2 Match all concepts

Term Meaning
CoroutineScope Scope
Dispatchers Thread choice
Job Waiting
SupervisorJob Isolation
CoroutineExceptionHandler Error catching

All lessons in Advanced

1 Advanced coroutines

  1. CoroutineScope
  2. Dispatchers
  3. Job
  4. SupervisorJob
  5. CoroutineExceptionHandler
  6. Summary - Advanced coroutines

2 Advanced Flow

  1. StateFlow
  2. SharedFlow
  3. Channel
  4. debounce and conflate
  5. flatMapLatest
  6. Summary - Advanced Flow

3 Ktor HTTP client

  1. Ktor client
  2. HttpClient
  3. GET
  4. POST
  5. JSON deserialization
  6. Summary - Ktor HTTP

4 Ktor server

  1. Ktor server
  2. Routing
  3. Application
  4. Plugins
  5. WebSocket
  6. Summary - Ktor server

5 kotlinx.serialization

  1. @Serializable
  2. Json
  3. @SerialName
  4. @Optional
  5. Polymorphism
  6. Summary - kotlinx.serialization

6 Exposed SQL

  1. Exposed
  2. Table
  3. Transaction
  4. CRUD
  5. Join
  6. Summary - Exposed SQL

7 Dependency injection

  1. Koin
  2. module
  3. single and factory
  4. by inject
  5. by viewModel
  6. Summary - DI

8 Advanced testing

  1. Testing coroutines
  2. Turbine
  3. Advanced MockK
  4. Testcontainers
  5. Property tests
  6. Summary - Advanced testing

9 Functional programming

  1. Immutability
  2. Pure functions
  3. Sequence
  4. Fold and recursion
  5. Monad
  6. Summary - Functional programming

10 Collection stdlib

  1. windowed
  2. chunked
  3. zip and unzip
  4. scan
  5. flatMap and flatten
  6. Summary - Collection stdlib

11 Reflection

  1. KClass
  2. KProperty
  3. KFunction
  4. call
  5. Annotations
  6. Summary - Reflection

12 Concurrency patterns

  1. Mutex
  2. Semaphore
  3. Producer-consumer
  4. Rate limiter
  5. Circuit breaker
  6. Summary - Concurrency patterns

13 Security

  1. Hashing
  2. HMAC
  3. AES
  4. SecureRandom
  5. PBKDF2
  6. Summary - Security

14 Advanced final

  1. Project design
  2. Ktor API
  3. Exposed DB
  4. Coroutines
  5. Putting it together