补充答疑例子

朱晔 · 朱晔 · commit cdca6446eae0 · 2020-07-05T19:01:34.000+08:00
diff --git a/src/main/java/org/geekbang/time/commonmistakes/java8/StreamDetailTest.java b/src/main/java/org/geekbang/time/commonmistakes/java8/StreamDetailTest.java
@@ -228,11 +228,29 @@ public void skipLimit() {
 
     @Test
     public void peek() {
-        orders.stream()
-                .filter(order -> order.getTotalPrice() > 40)
-                .peek(order -> System.out.println(order.toString()))
-                .map(Order::getCustomerName)
-                .collect(toList());
+        IntStream.rangeClosed(1, 10)
+                .peek(i -> {
+                    System.out.println("第一次peek");
+                    System.out.println(i);
+                })
+                .filter(i -> i > 5)
+                .peek(i -> {
+                    System.out.println("第二次peek");
+                    System.out.println(i);
+                })
+                .filter(i -> i % 2 == 0)
+                .forEach(i -> {
+                    System.out.println("最终结果");
+                    System.out.println(i);
+                });
+
+//        orders.stream()
+//                .filter(order -> order.getTotalPrice() > 40)
+//                .peek(order -> System.out.println(order.toString()))
+//                .map(Order::getCustomerName)
+//                .collect(toList());
+
+
     }
 
     @Test
diff --git a/src/main/java/org/geekbang/time/commonmistakes/troubleshootingtools/mat/JMapApplication.java b/src/main/java/org/geekbang/time/commonmistakes/troubleshootingtools/mat/JMapApplication.java
@@ -0,0 +1,32 @@
+package org.geekbang.time.commonmistakes.troubleshootingtools.mat;
+
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+import java.util.UUID;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+@SpringBootApplication
+@Slf4j
+public class JMapApplication implements CommandLineRunner {
+
+    //-Xmx512m -Xms512m
+    public static void main(String[] args) {
+        SpringApplication.run(JMapApplication.class, args);
+    }
+
+    @Override
+    public void run(String... args) throws Exception {
+        while (true) {
+            String payload = IntStream.rangeClosed(1, 1000000)
+                    .mapToObj(__ -> "a")
+                    .collect(Collectors.joining("")) + UUID.randomUUID().toString();
+            log.debug(payload);
+            TimeUnit.MILLISECONDS.sleep(1);
+        }
+    }
+}
