2.5 Added flatMapIterable examples

Froussios · Froussios · commit e1a6eb235ac5 · 2015-05-18T23:35:23.000+02:00
diff --git a/tests/java/itrx/chapter2/transforming/FlatMapIterableTest.java b/tests/java/itrx/chapter2/transforming/FlatMapIterableTest.java
@@ -0,0 +1,151 @@
+package itrx.chapter2.transforming;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Iterator;
+import java.util.List;
+
+import org.junit.Test;
+
+import rx.Observable;
+import rx.observers.TestSubscriber;
+
+public class FlatMapIterableTest {
+	
+	public static class Range implements Iterable<Integer> {
+
+		private static class RangeIterator implements Iterator<Integer> {
+			private int next;
+			private final int end;
+			 
+			RangeIterator(int start, int count) {
+				this.next = start;
+				this.end = start + count;
+			}
+			
+			@Override
+			public boolean hasNext() {
+				return next < end;
+			}
+
+			@Override
+			public Integer next() {
+				return next++;
+			}
+			
+		}
+		
+		private final int start;
+		private final int count;
+		
+		public Range(int start, int count) {
+			this.start = start;
+			this.count = count;
+		}
+		
+		@Override
+		public Iterator<Integer> iterator() {
+			return new RangeIterator(start, count);
+		}
+	}
+	
+	public static Iterable<Integer> range(int start, int count) {
+		List<Integer> list = new ArrayList<>();
+		for (int i=start ; i<start+count ; i++) {
+			list.add(i);
+		}
+		return list;
+	}
+	
+	public void exampleFlatMapIterable() {
+		Observable.range(1, 3)
+			.flatMapIterable(i -> range(1, i))
+			.subscribe(System.out::println);
+		
+		// 1
+		// 1
+		// 2
+		// 1
+		// 2
+		// 3
+	}
+	
+	public void exampleFlatMapIterableWithSelector() {
+		Observable.range(1, 3)
+			.flatMapIterable(
+				i -> range(1, i),
+				(ori, rv) -> ori * (Integer) rv)
+			.subscribe(System.out::println);
+		
+		// 1
+		// 2
+		// 4
+		// 3
+		// 6
+		// 9
+	}
+	
+	public void exampleFlatMapLazyIterable() {
+		Observable.range(1, 3)
+			.flatMapIterable(
+				i -> new Range(1, i),
+				(ori, rv) -> ori * (Integer) rv)
+			.subscribe(System.out::println);
+	
+	// 1
+	// 2
+	// 4
+	// 3
+	// 6
+	// 9
+	}
+	
+	
+	//
+	// Test
+	//
+	
+	@Test
+	public void testFlatMapIterable() {
+		TestSubscriber<Integer> tester = new TestSubscriber<>();
+		
+		Observable.range(1, 3)
+			.flatMapIterable(i -> range(1, i))
+			.subscribe(tester);
+		
+		tester.assertReceivedOnNext(Arrays.asList(1,1,2,1,2,3));
+		tester.assertTerminalEvent();
+		tester.assertNoErrors();
+	}
+	
+	@Test
+	public void testFlatMapIterableWithSelector() {
+		TestSubscriber<Integer> tester = new TestSubscriber<>();
+		
+		Observable.range(1, 3)
+			.flatMapIterable(
+				i -> range(1, i),
+				(ori, rv) -> ori * (Integer) rv)
+			.subscribe(tester);
+		
+		tester.assertReceivedOnNext(Arrays.asList(1,2,4,3,6,9));
+		tester.assertTerminalEvent();
+		tester.assertNoErrors();
+	}
+	
+	@Test
+	public void testFlatMapLazyIterable() {
+		TestSubscriber<Integer> tester = new TestSubscriber<>();
+		
+		Observable.range(1, 3)
+			.flatMapIterable(
+				i -> new Range(1, i),
+				(ori, rv) -> ori * (Integer) rv)
+			.subscribe(tester);
+		
+		tester.assertReceivedOnNext(Arrays.asList(1,2,4,3,6,9));
+		tester.assertTerminalEvent();
+		tester.assertNoErrors();
+	}
+
+}
