Using JsonUtils instead of fastjson

kafka-manager-common/pom.xml

@@ -104,5 +104,12 @@
             <groupId>javax.servlet</groupId>
             <artifactId>javax.servlet-api</artifactId>
         </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.12</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 </project>

kafka-manager-common/src/test/java/com/xiaojukeji/kafka/manager/common/utils/JsonUtilsTest.java

@@ -0,0 +1,18 @@
+package com.xiaojukeji.kafka.manager.common.utils;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class JsonUtilsTest {
+    @Test
+    public void testMapToJsonString() {
+        Map<String, Object> map = new HashMap<>();
+        map.put("key", "value");
+        map.put("int", 1);
+        String expectRes = "{\"key\":\"value\",\"int\":1}";
+        Assert.assertEquals(expectRes, JsonUtils.toJSONString(map));
+    }
+}