diff --git a/java/StringShitJudge.java b/java/StringShitJudge.java
new file mode 100644
index 0000000000000000000000000000000000000000..b2811e568c11fb0012af580418640777df3b2ded
--- /dev/null
+++ b/java/StringShitJudge.java
@@ -0,0 +1,22 @@
+package com.qishon.iss.qop.common;
+
+public class StringShitJudge {
+    public static void main(String[] args) {
+
+        String sex = null;
+        System.out.println("我的性别是" + judge(sex));
+    }
+
+    /**
+     * toString()、String.valueOf()、(String)
+     * @param sex
+     * @return
+     */
+    private static String judge(Object sex) {
+        if (String.valueOf(sex) != null) {
+            //do something...
+            return String.valueOf(sex);
+        }
+        return "";
+    }
+}
\ No newline at end of file