'完成第五部分'

vw2019 · vw2019 · commit d258bb2b7f46 · 2018-09-29T18:18:13.000+08:00
diff --git a/src/main/java/lambdasinaction/chap4/StreamBasic.java b/src/main/java/lambdasinaction/chap4/StreamBasic.java
@@ -1,6 +1,7 @@
 package lambdasinaction.chap4;
 
 import java.util.*;
+import java.util.function.Function;
 import java.util.stream.*;
 
 import static java.util.Comparator.comparing;
@@ -10,7 +11,7 @@
 
 public class StreamBasic {
 
-    public static void main(String...args){
+    public static void main(String... args) {
         // Java 7
         getLowCaloricDishesNamesInJava7(Dish.menu).forEach(System.out::println);
 
@@ -21,26 +22,26 @@ public static void main(String...args){
 
     }
 
-    public static List<String> getLowCaloricDishesNamesInJava7(List<Dish> dishes){
+    public static List<String> getLowCaloricDishesNamesInJava7(List<Dish> dishes) {
         List<Dish> lowCaloricDishes = new ArrayList<>();
-        for(Dish d: dishes){
-            if(d.getCalories() < 400){
+        for (Dish d : dishes) {
+            if (d.getCalories() < 400) {
                 lowCaloricDishes.add(d);
             }
         }
         List<String> lowCaloricDishesName = new ArrayList<>();
         Collections.sort(lowCaloricDishes, new Comparator<Dish>() {
-            public int compare(Dish d1, Dish d2){
+            public int compare(Dish d1, Dish d2) {
                 return Integer.compare(d1.getCalories(), d2.getCalories());
             }
         });
-        for(Dish d: lowCaloricDishes){
+        for (Dish d : lowCaloricDishes) {
             lowCaloricDishesName.add(d.getName());
         }
         return lowCaloricDishesName;
     }
 
-    public static List<String> getLowCaloricDishesNamesInJava8(List<Dish> dishes){
+    public static List<String> getLowCaloricDishesNamesInJava8(List<Dish> dishes) {
         return dishes.stream()
                 .filter(d -> d.getCalories() < 400)
                 .sorted(comparing(Dish::getCalories))
diff --git a/src/main/java/lambdasinaction/chap5/Demo522.java b/src/main/java/lambdasinaction/chap5/Demo522.java
@@ -0,0 +1,21 @@
+package lambdasinaction.chap5;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import static java.util.stream.Collectors.toList;
+
+/**
+ * @author vector
+ * @date: 2018/9/29 0029 15:48
+ */
+public class Demo522 {
+    public static void main(String[] args) {
+        List<String> hw = Arrays.asList("Hello", "World");
+        List<String> collect = hw.stream().map(word -> word.split("")).flatMap(Arrays::stream).distinct().collect(toList());
+        System.out.println(collect);
+    }
+}
diff --git a/src/main/java/lambdasinaction/chap5/Demo551.java b/src/main/java/lambdasinaction/chap5/Demo551.java
@@ -0,0 +1,36 @@
+package lambdasinaction.chap5;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+import static java.util.Comparator.comparing;
+import static java.util.stream.Collectors.joining;
+import static java.util.stream.Collectors.toList;
+
+/**
+ * @author vector
+ * @date: 2018/9/29 0029 16:48
+ */
+public class Demo551 {
+    public static void main(String[] args) {
+        List<Transaction> list = new ArrayList<>();
+        List<Transaction> list1 = list.stream().filter(item -> item.getYear() == 2011).sorted(comparing(Transaction::getValue)).collect(toList());
+
+        Set<String> set2 = list.stream().map(item -> item.getTrader().getCity()).collect(Collectors.toSet());
+
+        List<Trader> list3 = list.stream().map(Transaction::getTrader).filter(item -> item.getCity().equals("剑桥")).distinct().sorted(comparing(Trader::getName)).collect(toList());
+
+        String collect4 = list.stream().map(item -> item.getTrader().getName()).distinct().sorted().collect(joining());
+
+        boolean boolean5 = list.stream().anyMatch(item -> item.getTrader().getCity().equals("米兰"));
+
+        list.stream().filter(item->item.getTrader().getCity().equals("剑桥")).map(Transaction::getValue).forEach(System.out::println);
+
+        Optional<Integer> first7 = list.stream().map(Transaction::getValue).sorted(Integer::compareTo).limit(1).findFirst();
+
+        list.stream().min(comparing(Transaction::getValue));
+
+
+
+    }
+}
