add Collectors Demo

CodeCoderCoding · CodeCoderCoding · commit 8c1e6f4e0f52 · 2023-01-31T17:46:41.000+08:00
diff --git a/src/FDynamic/Stream/CollectorsDemo.java b/src/FDynamic/Stream/CollectorsDemo.java
@@ -0,0 +1,31 @@
+package FDynamic.Stream;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class CollectorsDemo {
+
+    public static void main(String[] args) {
+        List<Person> personList= Arrays.asList(
+                new Person("aaa", 18, new BigDecimal(123)),
+                new Person("aaa", 18, new BigDecimal(123)),
+                new Person("bbb", 19, new BigDecimal(124))
+        );
+        groupBy(personList);
+    }
+
+    /**
+     * 根据人员的name来进行分组
+     * @param personList
+     */
+    public static void groupBy(List<Person> personList){
+        Map<String, List<Person>> map=personList.stream()
+                .collect(Collectors.groupingBy(Person::getName));
+        System.out.println(map);
+    }
+
+}
