diff --git a/s-day07/src/com/inmind/functional_consumer03/Demo05.java b/s-day07/src/com/inmind/functional_consumer03/Demo05.java
new file mode 100644
index 0000000..1e75d64
--- /dev/null
+++ b/s-day07/src/com/inmind/functional_consumer03/Demo05.java
@@ -0,0 +1,34 @@
+package com.inmind.functional_consumer03;
+
+import java.util.function.Consumer;
+
+/*
+    在jdk1.8之后,java提供了一些常用的函数式接口供开发人员直接使用.
+
+    常用的函数式接口_Consumer
+    Interface Consumer<T>
+    抽象方法:
+    void accept(T t) 对给定的参数执行此操作。
+
+    注意:
+        1.Consumer表示一个消费者.只接受一个参数,没有返回值.
+        2.什么时候要使用Consumer接口??
+          当我们开发人员想自定义一个函数式接口,并且该接口中要定义一个接收一个参数,没有返回值的方法
+
+    需求:定义出一个使用常用函数式接口的方法,并对字符串进行消费操作(大写打印,小写打印)
+ */
+public class Demo05 {
+
+    public static void main(String[] args) {
+        //1.大写打印(lambda全写形式)
+        printString((String s)->{
+            System.out.println(s.toUpperCase());
+        },"aBcD");
+        //2.小写打印(lambda省略形式)
+        printString(s-> System.out.println(s.toLowerCase()),"aBcD");
+    }
+
+    public static void printString(Consumer<String> consumer, String s) {
+        consumer.accept(s);
+    }
+}
diff --git a/s-day07/src/com/inmind/functional_consumer03/MyInterface1.java b/s-day07/src/com/inmind/functional_consumer03/MyInterface1.java
new file mode 100644
index 0000000..6b492fd
--- /dev/null
+++ b/s-day07/src/com/inmind/functional_consumer03/MyInterface1.java
@@ -0,0 +1,6 @@
+package com.inmind.functional_consumer03;
+
+@FunctionalInterface
+public interface MyInterface1 {
+    void accept(String s);
+}
diff --git a/s-day07/src/com/inmind/functional_consumer03/MyInterface2.java b/s-day07/src/com/inmind/functional_consumer03/MyInterface2.java
new file mode 100644
index 0000000..74a6c45
--- /dev/null
+++ b/s-day07/src/com/inmind/functional_consumer03/MyInterface2.java
@@ -0,0 +1,6 @@
+package com.inmind.functional_consumer03;
+
+@FunctionalInterface
+public interface MyInterface2 {
+    void accept(Integer i);
+}
diff --git a/s-day07/src/com/inmind/functional_consumer03/MyInterface3.java b/s-day07/src/com/inmind/functional_consumer03/MyInterface3.java
new file mode 100644
index 0000000..6389b61
--- /dev/null
+++ b/s-day07/src/com/inmind/functional_consumer03/MyInterface3.java
@@ -0,0 +1,8 @@
+package com.inmind.functional_consumer03;
+
+import com.inmind.lambda01.Student;
+
+@FunctionalInterface
+public interface MyInterface3 {
+    void accept(Student s);
+}
diff --git a/s-day07/src/com/inmind/functional_interface02/Demo05.java b/s-day07/src/com/inmind/functional_interface02/Demo05.java
deleted file mode 100644
index a50283c..0000000
--- a/s-day07/src/com/inmind/functional_interface02/Demo05.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package com.inmind.functional_interface02;
-
-public class Demo05 {
-}