add stream流

huanhuande · huanhuande · commit 05a0e29845c2 · 2019-08-08T14:19:35.000+08:00
diff --git a/java-Test/src/main/java/Stream/Property.java b/java-Test/src/main/java/Stream/Property.java
@@ -0,0 +1,26 @@
+package Stream;
+
+import lombok.Data;
+
+/**
+ * @author huanfuan
+ * @version 1.0
+ * @date 2019/8/8 0008 下午 12:53
+ */
+@Data
+public class Property {
+
+    String  name;
+    // 距离，单位:米
+    Integer distance;
+    // 销量，月售
+    Integer sales;
+    // 价格，这里简单起见就写一个级别代表价格段
+    Integer priceLevel;
+    public Property(String name, int distance, int sales, int priceLevel) {
+        this.name = name;
+        this.distance = distance;
+        this.sales = sales;
+        this.priceLevel = priceLevel;
+    }
+}
diff --git a/java-Test/src/main/java/Stream/streamTest01.java b/java-Test/src/main/java/Stream/streamTest01.java
@@ -0,0 +1,44 @@
+package Stream;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+/**
+ * @author huanfuan
+ * @version 1.0
+ * @date 2019/8/8 0008 下午 12:54
+ */
+public class streamTest01 {
+    public static void main(String[] args) {
+        Property p1 = new Property("叫了个鸡", 1000, 500, 2);
+        Property p2 = new Property("张三丰饺子馆", 2300, 1500, 3);
+        Property p3 = new Property("永和大王", 580, 3000, 1);
+        Property p4 = new Property("肯德基", 6000, 200, 4);
+        List<Property> properties = Arrays.asList(p1, p2, p3, p4);
+
+        Collections.sort(properties,(x,y) ->x.distance.compareTo(y.distance));
+        String name = properties.get(0).name;
+        System.out.println("距离我最近的店铺是:" + name);
+
+        //stream操作
+        String name2=properties.stream().
+                sorted(Comparator.comparingInt(x ->x.distance))
+                .findFirst()
+                .get().name;
+        System.out.println("距离我最近的店铺是:" + name);
+
+        /*获取所有店铺的名称*/
+        List<String> names = properties.stream()
+                .map(p -> p.name)
+                .collect(Collectors.toList());
+
+        /*获取每个店铺的价格等级*/
+        Map<String, Integer> map = properties.stream()
+                .collect(Collectors.toMap(Property::getName, Property::getPriceLevel));
+
+
+        /*所有价格等级的店铺列表*/
+        Map<Integer, List<Property>> priceMap = properties.stream()
+                .collect(Collectors.groupingBy(Property::getPriceLevel));
+    }
+}
diff --git a/java-Test/src/main/java/Stream/streamTest02.java b/java-Test/src/main/java/Stream/streamTest02.java
@@ -0,0 +1,25 @@
+package Stream;
+
+import java.util.*;
+
+/**
+ * @author huanfuan
+ * @version 1.0
+ * @date 2019/8/8 0008 下午 2:07
+ */
+public class streamTest02 {
+    public static void main(String[] args) {
+        List<List<String>> lists = new ArrayList<>();
+        lists.add(Arrays.asList("apple", "click"));
+        lists.add(Arrays.asList("boss", "dig", "qq", "vivo"));
+        lists.add(Arrays.asList("c#", "biezhi"));
+
+        lists.stream()
+                .flatMap(Collection::stream)
+                .filter(str -> str.length()>2)
+                .count();
+
+
+      
+    }
+}
diff --git a/java-Test/src/main/java/Stream/streamTest03.java b/java-Test/src/main/java/Stream/streamTest03.java
@@ -0,0 +1,41 @@
+package Stream;
+
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+import java.util.stream.Collectors;
+
+/**
+ * @author huanfuan
+ * @version 1.0
+ * @date 2019/8/8 0008 下午 2:13
+ * Stream并行流
+ */
+public class streamTest03 {
+    public static void main(String[] args) {
+        Property p1 = new Property("叫了个鸡", 1000, 500, 2);
+        Property p2 = new Property("张三丰饺子馆", 2300, 1500, 3);
+        Property p3 = new Property("永和大王", 580, 3000, 1);
+        Property p4 = new Property("肯德基", 6000, 200, 4);
+        List<Property> properties = Arrays.asList(p1, p2, p3, p4);
+
+
+        /*筛选出价格等级小于4，按照距离排序的2个店铺名*/
+        properties.stream()
+                .filter(p -> p.priceLevel<4)
+                .sorted(Comparator.comparingInt(Property::getDistance))
+                .map(Property::getName)
+                .limit(2)
+                .collect(Collectors.toList());
+
+
+        /*调用 parallelStream 方法即能并行处理*/
+        properties.parallelStream()
+                .filter(p -> p.priceLevel<4)
+                .sorted(Comparator.comparingInt(Property::getDistance))
+                .map(Property::getName)
+                .limit(2)
+                .collect(Collectors.toList());
+
+    }
+}
diff --git a/java-Test/src/main/java/lambda/lambdaTest01.java b/java-Test/src/main/java/lambda/lambdaTest01.java
@@ -1,3 +1,5 @@
+package lambda;
+
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/java-Test/src/main/java/lambda/lambdaTest03.java b/java-Test/src/main/java/lambda/lambdaTest03.java
@@ -1,4 +1,4 @@
-/**
+package lambda; /**
  * @author huanfuan
  * @version 1.0
  * @date 2019/8/8 0008 上午 10:18
diff --git a/java-Test/src/main/java/lambda/lambdaTest06.java b/java-Test/src/main/java/lambda/lambdaTest06.java
@@ -1,3 +1,5 @@
+package lambda;
+
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/java-Test/src/main/java/lambda/lambdaTest07.java b/java-Test/src/main/java/lambda/lambdaTest07.java
@@ -1,3 +1,5 @@
+package lambda;
+
 import java.util.List;
 import java.util.stream.Collectors;
 
diff --git a/java-Test/src/main/java/lambda/lambdaTest08.java b/java-Test/src/main/java/lambda/lambdaTest08.java
@@ -1,4 +1,4 @@
-/**
+package lambda; /**
  * @author huanfuan
  * @version 1.0
  * @date 2019/8/8 0008 上午 11:19
diff --git a/java-Test/src/main/java/lambda/lambdaTest09.java b/java-Test/src/main/java/lambda/lambdaTest09.java
@@ -1,3 +1,5 @@
+package lambda;
+
 import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;
diff --git a/java-Test/src/main/java/lambda/lambdaTest10.java b/java-Test/src/main/java/lambda/lambdaTest10.java
@@ -1,3 +1,5 @@
+package lambda;
+
 import java.util.Arrays;
 import java.util.IntSummaryStatistics;
 import java.util.List;
diff --git a/java-Test/src/main/java/lambda/lanmbdaTest02.java b/java-Test/src/main/java/lambda/lanmbdaTest02.java
@@ -1,3 +1,5 @@
+package lambda;
+
 /**
  * @author huanfuan
  * @version 1.0

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,5 @@`
	`1`	`+package lambda;`
	`2`	`+`
`1`	`3`	`import java.util.Arrays;`
`2`	`4`	`import java.util.List;`
`3`	`5`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-/**`
	`1`	`+package lambda; /**`
`2`	`2`	`* @author huanfuan`
`3`	`3`	`* @version 1.0`
`4`	`4`	`* @date 2019/8/8 0008 上午 10:18`