[final drafts] Updated code according to the final drafts of chapters 7 and 8

build.gradle

@@ -24,7 +24,6 @@ dependencies {
     compile "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines_version"
 
     // Test libraries
-    compile "org.jetbrains.kotlin:kotlin-reflect"
     testCompile "org.jetbrains.kotlin:kotlin-test"
     testCompile "org.jetbrains.kotlin:kotlin-test-junit"
 

src/main/kotlin/chapter7/actor/actor.kt

@@ -1,5 +1,6 @@
 package chapter7.actor
 
+import kotlinx.coroutines.experimental.CommonPool
 import kotlinx.coroutines.experimental.async
 import kotlinx.coroutines.experimental.runBlocking
 
@@ -22,7 +23,7 @@ fun asyncIncrement(by: Int) = async {
     }
 }
 
-fun asyncDecrement(by: Int) = async {
+fun asyncDecrement(by: Int) = async(CommonPool) {
     for (i in 0 until by) {
         actorCounter.send(Action.DECREASE)
     }

src/main/kotlin/chapter7/actor/actorCounter.kt

@@ -4,19 +4,17 @@ import kotlinx.coroutines.experimental.channels.actor
 import kotlinx.coroutines.experimental.newSingleThreadContext
 
 private var counter = 0
-private var context = newSingleThreadContext("actor")
+private val context = newSingleThreadContext("actor")
 
 enum class Action {
     INCREASE,
     DECREASE
 }
 
-fun getCounter() : Int {
-    return counter
-}
+fun getCounter() = counter
 
-var actorCounter = actor<Action>(context) {
-    for (msg in channel){
+val actorCounter = actor<Action>(context) {
+    for (msg in channel) {
         when(msg) {
             Action.INCREASE -> counter++
             Action.DECREASE -> counter--

src/main/kotlin/chapter7/actor/interaction/actor_samples.kt

@@ -20,6 +20,8 @@ suspend fun bufferedActor() {
 
     bufferedPrinter.send("hello")
     bufferedPrinter.send("world")
+
+    bufferedPrinter.close()
 }
 
 suspend fun actorWithContext() {

src/main/kotlin/chapter7/confinement/thread_confinement.kt

@@ -17,7 +17,7 @@ fun main(args: Array<String>) = runBlocking {
 }
 
 var counter = 0
-var context = newSingleThreadContext("counter")
+val context = newSingleThreadContext("counter")
 
 fun asyncIncrement(by: Int) = async(context) {
     for (i in 0 until by) {

src/main/kotlin/chapter7/volatile/volatile.kt

@@ -17,7 +17,6 @@ class DataProcessor {
     }
 }
 
-
 fun main(args: Array<String>) {
 
 }

src/main/kotlin/chapter8/debugging.kt

@@ -19,6 +19,10 @@ fun main(args: Array<String>) = runBlocking {
 
 }
 
+private fun threadName() : String {
+    return Thread.currentThread().name
+}
+
 suspend fun automaticNaming() {
     val pool = newFixedThreadPoolContext(3, "myPool")
     val ctx = newSingleThreadContext("ctx")
@@ -26,13 +30,13 @@ suspend fun automaticNaming() {
     val tasks = mutableListOf<Deferred<Unit>>()
     for (i in 0..5) {
         val task = async(pool) {
-            println("Processing $i in ${Thread.currentThread().name}")
+            println("Processing $i in ${threadName()}")
 
             withContext(ctx) {
-                println("Step two of $i happening in thread ${Thread.currentThread().name}")
+                println("Step two of $i happening in thread ${threadName()}")
             }
 
-            println("Finishing $i in ${Thread.currentThread().name}")
+            println("Finishing $i in ${threadName()}")
 
         }
 
@@ -49,10 +53,10 @@ suspend fun specificNaming(){
     val ctx = newSingleThreadContext("ctx")
 
     withContext(pool + CoroutineName("main")) {
-        println("Running in ${Thread.currentThread().name}")
+        println("Running in ${threadName()}")
 
         withContext(ctx + CoroutineName("inner")) {
-            println("Switching to ${Thread.currentThread().name}")
+            println("Switching to ${threadName()}")
         }
     }
 }

src/main/kotlin/chapter8/sample_app.kt

@@ -11,11 +11,11 @@ data class User(
         val profession: String
 )
 
-class UserManager(private val datasource: Datasource) {
+class UserManager(private val dataSource: DataSource) {
     suspend fun getUser(id: Int): User {
-        val name = datasource.getNameAsync(id)
-        val age = datasource.getAgeAsync(id)
-        val profession = datasource.getProfessionAsync(id)
+        val name = dataSource.getNameAsync(id)
+        val age = dataSource.getAgeAsync(id)
+        val profession = dataSource.getProfessionAsync(id)
 
         // Wait for each of them, don't assume they are ready
         return User(name.await(),
@@ -24,7 +24,7 @@ class UserManager(private val datasource: Datasource) {
     }
 }
 
-interface Datasource {
+interface DataSource {
     fun getNameAsync(id: Int): Deferred<String>
     fun getAgeAsync(id: Int): Deferred<Int>
     fun getProfessionAsync(id: Int): Deferred<String>

src/test/kotlin/chapter8/SampleAppFT.kt

@@ -11,7 +11,7 @@ class SampleAppFT {
 
     @Test
     fun testHappyPath() = runBlocking {
-        val manager = UserManager(MockDatasource())
+        val manager = UserManager(MockDataSource())
 
         val user = manager.getUser(10)
         assertTrue { user.name == "Susan Calvin" }
@@ -21,7 +21,7 @@ class SampleAppFT {
 
     @Test
     fun testOppositeOrder() = runBlocking {
-        val manager = UserManager(MockOppositeDatasource())
+        val manager = UserManager(MockSlowDbDataSource())
 
         val user = manager.getUser(10)
         assertTrue { user.name == "Susan Calvin" }
@@ -31,7 +31,7 @@ class SampleAppFT {
 }
 
 // Mock a datasource that retrieves the data in a different order
-class MockOppositeDatasource: Datasource {
+class MockSlowDbDataSource: DataSource {
     // Mock getting the name from the database
     override fun getNameAsync(id: Int) = async {
         delay(1000)
@@ -52,7 +52,7 @@ class MockOppositeDatasource: Datasource {
 }
 
 // Mock a datasource that retrieves the data in the expected order
-class MockDatasource: Datasource {
+class MockDataSource: DataSource {
     // Mock getting the name from the database
     override fun getNameAsync(id: Int) = async {
         delay(200)