Optional

Author: MyHerux

README.md

@@ -9,4 +9,7 @@ Java8 Learning (java8学习) <br>
 
         ├── com.xu.java8.lambda	    // Lambda表达式
 	    ├── com.xu.java8.Optional	// java8-Optional类
-	    ├── com.xu.java8.Stream	    // java8-Stream接口
+	    ├── com.xu.java8.Stream	    // java8-Stream接口
+	    
+- java8-Optional类
+[Optional类的一些基本用法](https://github.com/MyHerux/java-java8-learning/blob/master/src/main/java/com/xu/java8/Optional/Optional.md)

src/main/java/com/xu/java8/Stream/Streams6.java

@@ -65,8 +65,8 @@ public static void main(String args[]) {
                 .filter(x -> JSONObject.fromObject(x).containsKey("type"))
                 .map(x -> JSONObject.fromObject(x).getString("type"))
                 .forEach(x -> {
-                    if (type_count.containsKey(x)) type_count.put(x.toString(), type_count.get(x) + 1);
-                    else type_count.put(x.toString(), 1);
+                    if (type_count.containsKey(x)) type_count.put(x, type_count.get(x) + 1);
+                    else type_count.put(x, 1);
                 });
         System.out.println(type_count.toString());
     }