quero map<Product, BigDecimal>

peas · Mar 13, 2014 · e396dc2 · e396dc2
1 parent e885903
commit e396dc2
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/src/main/java/br/com/casadocodigo/java8/Capitulo11.java b/src/main/java/br/com/casadocodigo/java8/Capitulo11.java
@@ -150,7 +150,14 @@ public static void main (String... args) throws Exception 	{
 		// que tipo de produto é o mais vendido (sum(VIDEO), sum(AUDIO))
 
 		// quero map<Product, BigDecimal>
+
+		payments.stream()
+			.map(Payment::getProducts)
+			.flatMap(p -> p.stream())
+			.collect(Collectors.groupingBy(Function.identity(), 
+					 Collectors.reducing(BigDecimal.ZERO, Product::getPrice, BigDecimal::add)));
 
+
 		// quero map<MonthYear, Map<Product, BigDecimal>>
 
 		// quero map<Customer, List<Payment>>, list ordenado por horario da compra