diff --git a/hippo4j-common/src/test/java/cn/hippo4j/common/toolkit/StringUtilTest.java b/hippo4j-common/src/test/java/cn/hippo4j/common/toolkit/StringUtilTest.java
index 45c2e8f9..a0938f67 100644
--- a/hippo4j-common/src/test/java/cn/hippo4j/common/toolkit/StringUtilTest.java
+++ b/hippo4j-common/src/test/java/cn/hippo4j/common/toolkit/StringUtilTest.java
@@ -1,21 +1,94 @@
-/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License.  You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package cn.hippo4j.common.toolkit;
-
-public class StringUtilTest {
-}
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package cn.hippo4j.common.toolkit;
+
+import org.junit.Test;
+
+import java.util.Objects;
+
+public class StringUtilTest {
+    
+    @Test
+    public void assertIsEmpty() {
+        String string = "";
+        Assert.isTrue(StringUtil.isEmpty(string));
+    }
+
+    @Test
+    public void assertIsNotEmpty() {
+        String string = "string";
+        Assert.isTrue(StringUtil.isNotEmpty(string));
+    }
+
+    @Test
+    public void emptyToNull() {
+        String string = "";
+        Assert.isNull(StringUtil.emptyToNull(string));
+    }
+
+    @Test
+    public void nullToEmpty() {
+        String string = "null";
+        Assert.notEmpty(StringUtil.nullToEmpty(string));
+    }
+
+    @Test
+    public void isNullOrEmpty() {
+        String string = "null";
+        Assert.isTrue(!StringUtil.isNullOrEmpty(string));
+    }
+
+    @Test
+    public void isBlank() {
+        String string = "";
+        Assert.isTrue(StringUtil.isBlank(string));
+    }
+
+ 
+    @Test
+    public void isNotBlank() {
+        String string = "null";
+        Assert.isTrue(StringUtil.isNotBlank(string));
+    }
+
+    @Test
+    public void isAllNotEmpty() {
+        String strings = "str";
+        Assert.isTrue(StringUtil.isAllNotEmpty(strings));
+    }
+
+    @Test
+    public void hasEmpty() {
+        String strings = "";
+        Assert.isTrue(StringUtil.hasEmpty(strings));
+    }
+
+    @Test
+    public void toUnderlineCase() {
+        String string = "str";
+        String s = StringUtil.toUnderlineCase(string);
+        Assert.isTrue(Objects.equals(s,"str"));
+    }
+
+    @Test
+    public void toSymbolCase() {
+        String string = "str";
+        String s = StringUtil.toSymbolCase(string,StringUtil.UNDERLINE);
+        Assert.isTrue(Objects.equals(s,"str"));
+    }
+}