diff --git a/src/chapter5/Example12.java b/src/chapter5/Example12.java
new file mode 100644
index 0000000..bf30d61
--- /dev/null
+++ b/src/chapter5/Example12.java
@@ -0,0 +1,17 @@
+package chapter5;
+
+import java.util.Enumeration;
+import java.util.Properties;
+
+public class Example12 {
+    public static void main(String[] args) {
+        // 获取当前系统信息
+        Properties prop = System.getProperties();
+        Enumeration names = prop.propertyNames();
+        while (names.hasMoreElements()) {
+            String key = (String) names.nextElement();
+            String value = prop.getProperty(key);
+            System.out.println(key + "=" + value);
+        }
+    }
+}