diff --git a/com/study/demo12/CodeGenerator.java b/com/study/demo12/CodeGenerator.java
new file mode 100644
index 0000000..8739c2a
--- /dev/null
+++ b/com/study/demo12/CodeGenerator.java
@@ -0,0 +1,5 @@
+package com.study.demo12;
+
+public interface CodeGenerator {
+    String generate();
+}
diff --git a/com/study/demo12/LoginCodeGenerator.java b/com/study/demo12/LoginCodeGenerator.java
new file mode 100644
index 0000000..eae5b89
--- /dev/null
+++ b/com/study/demo12/LoginCodeGenerator.java
@@ -0,0 +1,8 @@
+package com.study.demo12;
+
+public class LoginCodeGenerator implements CodeGenerator {
+    @Override
+    public String generate() {
+        return "LOGIN" + System.currentTimeMillis();
+    }
+}
diff --git a/com/study/demo12/PaymentCodeGenerator.java b/com/study/demo12/PaymentCodeGenerator.java
new file mode 100644
index 0000000..3a9bc04
--- /dev/null
+++ b/com/study/demo12/PaymentCodeGenerator.java
@@ -0,0 +1,8 @@
+package com.study.demo12;
+
+public class PaymentCodeGenerator implements CodeGenerator {
+    @Override
+    public String generate() {
+        return "PAY" + System.currentTimeMillis();
+    }
+}
diff --git a/com/study/demo12/TestCodeGenerator.java b/com/study/demo12/TestCodeGenerator.java
new file mode 100644
index 0000000..67d293f
--- /dev/null
+++ b/com/study/demo12/TestCodeGenerator.java
@@ -0,0 +1,11 @@
+package com.study.demo12;
+
+public class TestCodeGenerator {
+    public static void main(String[] args) {
+        CodeGenerator loginGenerator = new LoginCodeGenerator();
+        CodeGenerator paymentGenerator = new PaymentCodeGenerator();
+
+        System.out.println("登录验证码: " + loginGenerator.generate());
+        System.out.println("支付校验码: " + paymentGenerator.generate());
+    }
+}
diff --git a/com/study/demo12/TestVerifyCodeLogic.java b/com/study/demo12/TestVerifyCodeLogic.java
new file mode 100644
index 0000000..341f408
--- /dev/null
+++ b/com/study/demo12/TestVerifyCodeLogic.java
@@ -0,0 +1,14 @@
+package com.study.demo12;
+
+public class TestVerifyCodeLogic {
+    public static void main(String[] args) {
+        String timestamp = String.valueOf(System.currentTimeMillis());
+        String last4Digits = timestamp.substring(timestamp.length() - 4);
+        String code = "CODE" + last4Digits;
+
+        System.out.println("完整时间戳: " + timestamp);
+        System.out.println("时间戳后4位: " + last4Digits);
+        System.out.println("生成的验证码: " + code);
+        System.out.println("验证码格式正确: " + (code.startsWith("CODE") && code.length() == 8));
+    }
+}
diff --git a/com/study/demo12/VerifyCodeFrame.java b/com/study/demo12/VerifyCodeFrame.java
new file mode 100644
index 0000000..643fd4a
--- /dev/null
+++ b/com/study/demo12/VerifyCodeFrame.java
@@ -0,0 +1,38 @@
+package com.study.demo12;
+
+import java.awt.*;
+import java.awt.event.*;
+
+public class VerifyCodeFrame extends Frame {
+    private Label codeLabel;
+
+    public VerifyCodeFrame() {
+        setTitle("验证码生成窗口");
+        setSize(300, 150);
+        setLayout(new FlowLayout());
+
+        Button codeButton = new Button("获取验证码");
+        codeLabel = new Label("点击按钮获取验证码");
+
+        codeButton.addActionListener(e -> {
+            String timestamp = String.valueOf(System.currentTimeMillis());
+            String last4Digits = timestamp.substring(timestamp.length() - 4);
+            codeLabel.setText("CODE" + last4Digits);
+        });
+
+        addWindowListener(new WindowAdapter() {
+            @Override
+            public void windowClosing(WindowEvent e) {
+                System.exit(0);
+            }
+        });
+
+        add(codeButton);
+        add(codeLabel);
+        setVisible(true);
+    }
+
+    public static void main(String[] args) {
+        new VerifyCodeFrame();
+    }
+}