clean unit test code

src/test/java/com/alibaba/Utils.kt

@@ -20,7 +20,7 @@ fun expandThreadPool(executor: ExecutorService) {
     // toList, avoid lazy
     val list: List<Future<*>> = (0 until count).map {
         executor.submit { Thread.sleep(100) }
-    }.toList()
+    }
 
     list.forEach { it.get() }
 }
@@ -122,12 +122,12 @@ fun <T> printTtlInstances(ttlInstances: TtlInstances<T>, title: String = "") {
 
 typealias  TtlValues<T> = Map<String, T>
 
-fun <T> copyTtlValues(ttlInstances: ConcurrentMap<String, TransmittableThreadLocal<T>>): TtlValues<T> =
+fun <T> copyTtlValues(ttlInstances: TtlInstances<T>): TtlValues<T> =
         ttlInstances.filter { (_, v) -> v.get() != null }.map { (k, v) -> Pair(k, v.get()) }.toMap()
 
 
 fun <T> assertTtlValues(copied: TtlValues<T>, vararg asserts: String?) {
-    val message = "Assert Fail:\ncopyTtlValues: " + copied + "\n asserts: " + Arrays.toString(asserts)
+    val message = "Assert Fail:\ncopyTtlValues: $copied\n asserts: ${Arrays.toString(asserts)}"
 
     if (asserts.size % 2 != 0) {
         throw IllegalStateException("should even count! $message")

src/test/java/com/alibaba/third_part_lib_test/ForkJoinPoolTest.kt

@@ -41,7 +41,7 @@ class ForkJoinPoolTest {
 
 
 internal class SumTask(private val numbers: LongRange) : RecursiveTask<Long>() {
-    var execCounter = AtomicInteger(0)
+    val execCounter = AtomicInteger(0)
 
     override fun compute(): Long? {
         execCounter.incrementAndGet()

src/test/java/com/alibaba/ttl/TtlCallableTest.kt

@@ -97,12 +97,10 @@ class TtlCallableTest {
         val ttlCallable = TtlCallable.get(call, true)
         assertSame(call, ttlCallable.callable)
 
-        var future = executorService.submit(ttlCallable)
-        assertEquals("ok", future.get())
+        assertEquals("ok", executorService.submit(ttlCallable).get())
 
-        future = executorService.submit(ttlCallable)
         try {
-            future.get()
+            executorService.submit(ttlCallable).get()
             fail()
         } catch (expected: ExecutionException) {
             assertThat<Throwable>(expected.cause, instanceOf(IllegalStateException::class.java))

src/test/java/com/alibaba/ttl/TtlRunnableTest.kt

@@ -189,12 +189,10 @@ class TtlRunnableTest {
         val task = Task("1", ttlInstances)
         val ttlRunnable = TtlRunnable.get(task, true)
 
-        var future = executorService.submit(ttlRunnable)
-        assertNull(future.get())
+        assertNull(executorService.submit(ttlRunnable).get())
 
-        future = executorService.submit(ttlRunnable)
         try {
-            future.get()
+            executorService.submit(ttlRunnable).get()
             fail()
         } catch (expected: ExecutionException) {
             assertThat<Throwable>(expected.cause, instanceOf(IllegalStateException::class.java))

src/test/java/com/alibaba/ttl/testmodel/Call.kt

@@ -9,7 +9,7 @@ import java.util.concurrent.ConcurrentMap
 /**
  * @author Jerry Lee (oldratlee at gmail dot com)
  */
-class Call(val tag: String, private val ttlInstances: ConcurrentMap<String, TransmittableThreadLocal<String>> = ConcurrentHashMap()) : Callable<String> {
+class Call(private val tag: String, private val ttlInstances: ConcurrentMap<String, TransmittableThreadLocal<String>> = ConcurrentHashMap()) : Callable<String> {
 
     lateinit var copied: Map<String, String>
 

src/test/java/com/alibaba/ttl/testmodel/CallbackTestTransmittableThreadLocal.kt

@@ -8,9 +8,9 @@ import java.util.concurrent.atomic.AtomicInteger
  * @author Jerry Lee (oldratlee at gmail dot com)
  */
 class CallbackTestTransmittableThreadLocal : TransmittableThreadLocal<FooPojo>() {
-    var copyCounter = AtomicInteger()
-    var beforeExecuteCounter = AtomicInteger()
-    var afterExecuteCounter = AtomicInteger()
+    val copyCounter = AtomicInteger()
+    val beforeExecuteCounter = AtomicInteger()
+    val afterExecuteCounter = AtomicInteger()
 
     override fun copy(parentValue: FooPojo): FooPojo {
         copyCounter.incrementAndGet()