Future in Vavr

This commit is contained in:
Ahmed Tawila 2017-12-05 20:22:05 +02:00
parent fec5927d90
commit c489044f0b
2 changed files with 57 additions and 7 deletions

View File

@ -9,4 +9,12 @@ public class Util {
public static int divideByZero(int num) {
return num / 0;
}
public static String getSubstringMinusOne(String s) {
return s.substring(-1);
}
public static String getSubstringMinusTwo(String s) {
return s.substring(-2);
}
}

View File

@ -4,6 +4,7 @@ import static org.assertj.core.api.Assertions.assertThat;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executors;
import org.junit.Test;
@ -15,6 +16,17 @@ import io.vavr.control.Try;
public class FutureTest {
@Test
public void whenChangeExecutorService_thenCorrect() {
String initialValue = "Welcome to ";
Future<String> resultFuture = Future.of(
Executors.newSingleThreadExecutor(),
() -> Util.appendData(initialValue));
String result = resultFuture.get();
assertThat(result).isEqualTo("Welcome to Baeldung!");
}
@Test
public void whenAppendData_thenCorrect1() {
String initialValue = "Welcome to ";
@ -40,8 +52,8 @@ public class FutureTest {
public void whenAppendData_thenSuccess() {
String initialValue = "Welcome to ";
Future<String> resultFuture = Future.of(() -> Util.appendData(initialValue))
.onSuccess(finalResult -> System.out.println("Successfully Completed - Result: " + finalResult))
.onFailure(finalResult -> System.out.println("Failed - Result: " + finalResult));
.onSuccess(finalResult -> System.out.println("Successfully Completed - Result: " + finalResult))
.onFailure(finalResult -> System.out.println("Failed - Result: " + finalResult));
String result = resultFuture.get();
assertThat(result).isEqualTo("Welcome to Baeldung!");
@ -51,8 +63,8 @@ public class FutureTest {
public void whenChainingCallbacks_thenCorrect() {
String initialValue = "Welcome to ";
Future<String> resultFuture = Future.of(() -> Util.appendData(initialValue))
.andThen(finalResult -> System.out.println("Completed - 1: " + finalResult))
.andThen(finalResult -> System.out.println("Completed - 2: " + finalResult));
.andThen(finalResult -> System.out.println("Completed - 1: " + finalResult))
.andThen(finalResult -> System.out.println("Completed - 2: " + finalResult));
String result = resultFuture.get();
assertThat(result).isEqualTo("Welcome to Baeldung!");
@ -109,14 +121,14 @@ public class FutureTest {
@Test
public void whenCallZip_thenCorrect() {
Future<Tuple2<String, Integer>> future = Future.of(() -> "John")
.zip(Future.of(() -> new Integer(5)));
.zip(Future.of(() -> new Integer(5)));
future.await();
assertThat(future.get()).isEqualTo(Tuple.of("John", new Integer(5)));
}
@Test
public void whenAppendData_thenFutureNotEmptyd() throws InterruptedException, ExecutionException {
public void whenConvertToCompletableFuture_thenCorrect() throws InterruptedException, ExecutionException {
String initialValue = "Welcome to ";
Future<String> resultFuture = Future.of(() -> Util.appendData(initialValue));
CompletableFuture<String> convertedFuture = resultFuture.toCompletableFuture();
@ -127,9 +139,39 @@ public class FutureTest {
@Test
public void whenCallMap_thenCorrect() {
Future<String> futureResult = Future.of(() -> new StringBuilder("from Baeldung"))
.map(a -> "Hello " + a);
.map(a -> "Hello " + a);
futureResult.await();
assertThat(futureResult.get()).isEqualTo("Hello from Baeldung");
}
@Test
public void whenFutureFails_thenGetErrorMessage() {
Future<String> resultFuture = Future.of(() -> Util.getSubstringMinusOne("Hello"));
Future<String> errorMessageFuture = resultFuture.recover(Throwable::getMessage);
String errorMessage = errorMessageFuture.get();
assertThat(errorMessage).isEqualTo("String index out of range: -1");
}
@Test
public void whenFutureFails_thenGetAnotherFuture() {
Future<String> resultFuture = Future.of(() -> Util.getSubstringMinusOne("Hello"));
Future<String> errorMessageFuture = resultFuture.recoverWith(a -> Future.of(a::getMessage));
String errorMessage = errorMessageFuture.get();
assertThat(errorMessage).isEqualTo("String index out of range: -1");
}
@Test
public void whenBothFuturesFail_thenGetErrorMessage() {
Future<String> future1 = Future.of(() -> Util.getSubstringMinusOne("Hello"));
Future<String> future2 = Future.of(() -> Util.getSubstringMinusTwo("Hello"));
Future<String> errorMessageFuture = future1.fallbackTo(future2);
Future<Throwable> errorMessage = errorMessageFuture.failed();
assertThat(
errorMessage.get().getMessage())
.isEqualTo("String index out of range: -1");
}
}