diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Bank.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Bank.java
new file mode 100644
index 0000000000000000000000000000000000000000..759883802dce8d87fc5eed3e5533fd8683ef2ae5
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Bank.java
@@ -0,0 +1,23 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+public class Bank {
+    // 信用验证
+    public boolean checkCredit(String user) {
+        if ("zhangsan".equals(user)) {
+
+            return true;
+        }
+        throw new IllegalArgumentException("买家信用不够");
+    }
+
+    public void dealMoney(Buyer buyer, Homer homer) {
+        homer.money += homer.home.price;
+        buyer.money -= homer.home.price;
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Buyer.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Buyer.java
new file mode 100644
index 0000000000000000000000000000000000000000..91d0f021c88ff2f144168cc2e2ddb638c52753a0
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Buyer.java
@@ -0,0 +1,33 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+public class Buyer {
+    /**
+     * 姓名
+     */
+    public String name;
+    /**
+     * 拥有的金钱
+     */
+    public int money;
+
+    public Home home;
+
+
+    public Buyer(String name, int money) {
+        this.money = money;
+        this.name = name;
+    }
+
+    public void buyHome(Mediator mediator) throws Exception {
+        Homer homer = mediator.findHomer();
+        mediator.checkCredit(this);
+        mediator.checkMoney(this.money, homer.home.price);
+        mediator.deal(this, homer);
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Home.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Home.java
new file mode 100644
index 0000000000000000000000000000000000000000..cba24ad2f366c123996bd4ecd3aacbf413b1e7a3
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Home.java
@@ -0,0 +1,24 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+import lombok.ToString;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+@ToString
+public class Home {
+    // 户主
+    public String master;
+    // 价格
+    public int price;
+
+
+
+    public Home(String master, int price) {
+        this.master = master;
+        this.price = price;
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/HomeRegister.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/HomeRegister.java
new file mode 100644
index 0000000000000000000000000000000000000000..314e2175c1caef69ddc884deac4480660a9da1b3
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/HomeRegister.java
@@ -0,0 +1,63 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+public class HomeRegister {
+
+    private Map<String, Home> register = new HashMap<>();
+
+    /**
+     * 办理房产证，注册房源信息
+     *
+     * @param name
+     * @param home
+     */
+    public void register(String name, Home home) {
+        register.put(name, home);
+    }
+
+    /**
+     * 交易
+     *
+     * @param buyer
+     * @param homer
+     * @throws Exception
+     */
+    public void deal(Buyer buyer, Homer homer) throws Exception {
+        Home home = register.get(homer.name);
+        if (home == null) {
+            throw new Exception("卖家没有登记的房源 " + homer.name);
+        }
+        if (homer.home != home) {
+            throw new Exception("卖家登记的房源和买卖的不一致 " + homer.name);
+        }
+        Home remove = register.remove(homer.name);
+        register.put(buyer.name, remove);
+        buyer.home = homer.home;
+        homer.home = null;
+        buyer.home.master = buyer.name;
+
+    }
+
+    /**
+     * 房源是否存在
+     *
+     * @param name
+     * @param home
+     * @return
+     */
+    public boolean homeExist(String name, Home home) {
+        Home home1 = register.get(name);
+        if (home1 == home) {
+            return true;
+        }
+        return false;
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Homer.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Homer.java
new file mode 100644
index 0000000000000000000000000000000000000000..cbb4f59d4358a0a74775dcf72048d5f2b703b3aa
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Homer.java
@@ -0,0 +1,23 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+import lombok.ToString;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+@ToString
+public class Homer {
+    public String name;
+    public Home home;
+
+    public int money;
+
+
+    public Homer(String name, Home home) {
+        this.name = name;
+        this.home = home;
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Main.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Main.java
new file mode 100644
index 0000000000000000000000000000000000000000..8df55041a2056cbad34722cf890f36efb1e5f39b
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Main.java
@@ -0,0 +1,37 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+public class Main {
+    public static void main(String[] args) throws Exception {
+        HomeRegister homeRegister = new HomeRegister();
+        Mediator m = new Mediator(homeRegister);
+        Bank bank = new Bank();
+        m.setBank(bank);
+
+        String homerName = "lisi";
+        Home home = new Home(homerName,100000);
+        homeRegister.register(homerName,home);
+        Homer homer = new Homer(homerName,home);
+        // 申请卖房
+        m.registerHomer(homer);
+
+        // 买房流程
+        String buyerName = "zhangsan";
+
+        Buyer buyer = new Buyer(buyerName,2000);
+        System.out.println("买家买了房子 ：买家" + buyer.name + " 房子"+ buyer.home +" 余额"+buyer.money);
+        System.out.println("卖家卖了房子 ：卖家" + homer.name + " 房子"+ homer.home +" 余额"+homer.money);
+        System.out.println("买房前");
+        buyer.buyHome(m);
+
+        System.out.println("买家买了房子 ：买家" + buyer.name + " 房子"+ buyer.home +" 余额"+buyer.money);
+        System.out.println("卖家卖了房子 ：卖家" + homer.name + " 房子"+ homer.home +" 余额"+homer.money);
+
+
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Mediator.java b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Mediator.java
new file mode 100644
index 0000000000000000000000000000000000000000..0b222be93ec0a02b2be13c5d50574874de19920e
--- /dev/null
+++ b/java/com/kongxiang/raindrop/dp/type/behavior/mediator/Mediator.java
@@ -0,0 +1,58 @@
+package com.kongxiang.raindrop.dp.type.behavior.mediator;
+
+/**
+ * @author 孔翔
+ * @since 2023-10-19
+ * copyright for author : 孔翔 at 2023-10-19
+ * dp
+ */
+public class Mediator {
+
+    private HomeRegister homeRegister;
+    Bank bank;
+
+    public Mediator(HomeRegister aHomeRegister) {
+        this.homeRegister = aHomeRegister;
+    }
+
+    public void setBank(Bank bank) {
+        this.bank = bank;
+    }
+
+    /**
+     * 卖房者
+     */
+    private Homer homer;
+
+    public void registerHomer(Homer homer) {
+        if (null != homer.home) {
+
+        }
+        this.homer = homer;
+
+    }
+
+    public Homer findHomer() {
+        return homer;
+    }
+
+    public boolean checkCredit(Buyer buyer) throws Exception {
+         return bank.checkCredit(buyer.name);
+    }
+
+    public void checkMoney(int money, int price) {
+        if (money <= price){
+            throw new IllegalArgumentException("买家金额不够");
+        }
+    }
+
+    /**
+     * 交易
+     * @param buyer
+     * @param homer
+     */
+    public void deal(Buyer buyer, Homer homer) throws Exception {
+        bank.dealMoney(buyer,homer);
+        homeRegister.deal(buyer,homer);
+    }
+}
diff --git a/java/com/kongxiang/raindrop/dp/type/behavior/observer/pubsub/Dispatcher.java b/java/com/kongxiang/raindrop/dp/type/behavior/observer/pubsub/Dispatcher.java
deleted file mode 100644
index 07d304ab5ea82d7308f689055fd325d8bf3a1d86..0000000000000000000000000000000000000000
--- a/java/com/kongxiang/raindrop/dp/type/behavior/observer/pubsub/Dispatcher.java
+++ /dev/null
@@ -1,41 +0,0 @@
-package com.kongxiang.raindrop.dp.type.behavior.observer.pubsub;
-
-import com.kongxiang.raindrop.dp.type.behavior.observer.Observer;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * @author 孔翔
- * @since 2023-10-19
- * copyright for author : 孔翔 at 2023-10-19
- * dp
- */
-public class Dispatcher {
-
- /**
-  * 维护观察者的列表
-  */
- protected List<Observer> observerList = new ArrayList<>();
-
- /**
-  * 增加一个观察者
-  */
- public void register(Observer observer) {
-  observerList.add(observer);
- }
-
- /**
-  * 移除一个观察者
-  */
- public void remove(Observer observer) {
-  observerList.remove(observer);
- }
-
- /**
-  * 通知方法
-  */
- public void notifyAllObserver() {
-  observerList.forEach((o) -> o.update(this));
- }
-}