diff --git a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/utils/http/IPAddress.java b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/utils/http/IPAddress.java
index 3b18564..14283ed 100644
--- a/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/utils/http/IPAddress.java
+++ b/src/main/java/cn/edu/hfut/rmdjzz/projectmanagement/utils/http/IPAddress.java
@@ -16,7 +16,10 @@ public class IPAddress {
 
     public static IPAddress of(String ip) {
         long ipHex = 0;
-        ip = ip.substring(0, ip.indexOf(':'));
+        int portIndex = ip.indexOf(':');
+        if (portIndex != -1) {
+            ip = ip.substring(0, ip.indexOf(':'));
+        }
         String[] split = ip.split("\\.");
         for (String s : split) {
             ipHex = (ipHex << 8) + Integer.parseInt(s);
diff --git a/src/test/java/cn/edu/hfut/rmdjzz/projectmanagement/SerializeTests.java b/src/test/java/cn/edu/hfut/rmdjzz/projectmanagement/SerializeTests.java
index 75b45ef..d1bdda6 100644
--- a/src/test/java/cn/edu/hfut/rmdjzz/projectmanagement/SerializeTests.java
+++ b/src/test/java/cn/edu/hfut/rmdjzz/projectmanagement/SerializeTests.java
@@ -22,7 +22,9 @@ public class SerializeTests {
     @SneakyThrows
     @Test
     public void serializeTime() {
-        System.out.println(objectMapper.readValue("1657166400", LocalDateTime.class));
+        String timestamp = objectMapper.writeValueAsString(LocalDateTime.now());
+        System.out.println(timestamp);
+        System.out.println(objectMapper.readValue(timestamp, LocalDateTime.class));
     }
 
     @SneakyThrows