code modified

Author: pratikdas

kotlin/coroutines/src/main/kotlin/io/pratik/CoroutineAsync.kt

@@ -9,7 +9,6 @@ fun main() = runBlocking{
     val taskDeferred = async {
         generateUniqueID()
     }
-
     val taskResult = taskDeferred.await()
 
     println("program run ends...:  ${taskResult}  ${Thread.currentThread().name}")

kotlin/coroutines/src/main/kotlin/io/pratik/CoroutineCancelYield.kt

@@ -3,6 +3,7 @@ package io.pratik
 import kotlinx.coroutines.*
 import java.io.File
 
+
 fun main() = runBlocking{
     try {
         val job1 = launch {
@@ -22,7 +23,7 @@ fun main() = runBlocking{
         job1.join()
         job2.join()
 
-    } catch (e: Exception) {
+    } catch (e: CancellationException) {
         // clean up code
 
     }

kotlin/coroutines/src/main/kotlin/io/pratik/CoroutineDispatch.kt

@@ -1,13 +1,17 @@
 package io.pratik
 
 import kotlinx.coroutines.*
+import kotlin.coroutines.ContinuationInterceptor
 
 fun main() = runBlocking {
-   /* launch {
+    println(coroutineContext)
+    launch {
+        println(
+            "launch default: running in  thread ${Thread.currentThread().name} ${coroutineContext[ContinuationInterceptor]}")
         longTask()
-    }*/
+    }
 
-    /*launch(Dispatchers.Unconfined) { // not confined -- will work with main thread
+   /* launch(Dispatchers.Unconfined) { // not confined -- will work with main thread
         println("Unconfined : running in thread ${Thread.currentThread().name}")
         longTask()
     }*/
@@ -19,17 +23,17 @@ fun main() = runBlocking {
             longTask()
         }
     }*/
-   launch(newSingleThreadContext("MyThread")) { // will get its own new thread
+  /* launch(newSingleThreadContext("MyThread")) { // will get its own new thread
         println("newSingleThreadContext: running in  thread ${Thread.currentThread().name}")
         longTask()
-    }
+    }*/
     println("completed tasks")
 }
 
 
 suspend fun longTask(){
-   // println("executing longTask on...: ${Thread.currentThread().name}")
+    println("executing longTask on...: ${Thread.currentThread().name}")
     delay(1000)
-   // println("longTask ends on thread ...: ${Thread.currentThread().name}")
+    println("longTask ends on thread ...: ${Thread.currentThread().name}")
 }
 

kotlin/coroutines/src/main/kotlin/io/pratik/CoroutineWithLaunch.kt

@@ -1,18 +1,16 @@
 package io.pratik
 
 import kotlinx.coroutines.*
+import kotlin.coroutines.EmptyCoroutineContext
 
 fun main() = runBlocking{
     println("My program runs...: ${Thread.currentThread().name}")
 
-    val job:Job = launch {
+    val job:Job = launch (EmptyCoroutineContext, CoroutineStart.DEFAULT){
         longRunningTaskSuspended()
     }
 
     job.join()
-    /*runBlocking {
-        delay(2000)
-    }*/
 
     println("My program run ends...: ${Thread.currentThread().name}")
 }

kotlin/coroutines/src/main/kotlin/io/pratik/SuspendingFunction.kt

@@ -0,0 +1,36 @@
+package io.pratik
+
+import kotlinx.coroutines.*
+import java.time.Instant
+import kotlin.concurrent.thread
+
+
+fun main() = runBlocking{
+    println("${Instant.now()}: My program runs...: ${Thread.currentThread().name}")
+    val productId = findProduct()
+
+    launch (Dispatchers.Unconfined) {
+        val price = fetchPrice(productId)
+    }
+    updateProduct()
+    println("${Instant.now()}: My program run ends...: " +
+            "${Thread.currentThread().name}")
+}
+
+suspend fun fetchPrice(productId: String) : Double{
+    println("${Instant.now()}: fetchPrice starts on...: ${Thread.currentThread().name} ")
+    delay(2000)
+    println("${Instant.now()}: fetchPrice ends on...: ${Thread.currentThread().name} ")
+    return 234.5
+}
+
+fun findProduct() : String{
+    println("${Instant.now()}: findProduct on...: ${Thread.currentThread().name}")
+    return "P12333"
+}
+
+fun updateProduct() : String{
+    println("${Instant.now()}: updateProduct on...: ${Thread.currentThread().name}")
+    return "Product updated"
+}
+