fix bugs

hutool-json/src/test/java/cn/hutool/json/XMLTest.java

@@ -0,0 +1,15 @@
+package cn.hutool.json;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class XMLTest {
+
+	@SuppressWarnings("ConstantConditions")
+	@Test
+	public void toXmlTest(){
+		final JSONObject put = JSONUtil.createObj().put("aaa", "你好").put("键2", "test");
+		final String s = JSONUtil.toXmlStr(put);
+		Assert.assertEquals("<aaa>你好</aaa><键2>test</键2>", s);
+	}
+}