diff --git a/query_test.go b/query_test.go
index 173cdd3..41620a6 100644
--- a/query_test.go
+++ b/query_test.go
@@ -1,6 +1,7 @@
 package jsonquery
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/antchfx/xpath"
@@ -102,3 +103,134 @@ func TestNavigator(t *testing.T) {
 		t.Fatalf("node type is not DocumentNode")
 	}
 }
+
+func TestToXML(t *testing.T) {
+	s := `{
+	"name":"John",
+	"age":31, 
+	"female":false 
+  }`
+	doc, _ := Parse(strings.NewReader(s))
+	expected := `<?xml version="1.0" encoding="utf-8"?><root><age>31</age><female>false</female><name>John</name></root>`
+	if got := doc.OutputXML(); got != expected {
+		t.Fatalf("expected %s, but got %s", expected, got)
+	}
+}
+
+func TestArrayToXML(t *testing.T) {
+	s := `[1,2,3,4]`
+	doc, _ := Parse(strings.NewReader(s))
+	expected := `<?xml version="1.0" encoding="utf-8"?><root><1>1</1><2>2</2><3>3</3><4>4</4></root>`
+	if got := doc.OutputXML(); got != expected {
+		t.Fatalf("expected %s, but got %s", expected, got)
+	}
+}
+
+func TestNestToArray(t *testing.T) {
+	s := `{
+		"address": {
+		  "city": "Nara",
+		  "postalCode": "630-0192",
+		  "streetAddress": "naist street"
+		},
+		"age": 26,
+		"name": "John",
+		"phoneNumbers": [
+		  {
+			"number": "0123-4567-8888",
+			"type": "iPhone"
+		  },
+		  {
+			"number": "0123-4567-8910",
+			"type": "home"
+		  }
+		]
+	  }`
+	doc, _ := Parse(strings.NewReader(s))
+	expected := `<?xml version="1.0" encoding="utf-8"?><root><address><city>Nara</city><postalCode>630-0192</postalCode><streetAddress>naist street</streetAddress></address><age>26</age><name>John</name><phoneNumbers><number>0123-4567-8888</number><type>iPhone</type></phoneNumbers><phoneNumbers><number>0123-4567-8910</number><type>home</type></phoneNumbers></root>`
+	if got := doc.OutputXML(); got != expected {
+		t.Fatalf("expected \n%s, but got \n%s", expected, got)
+	}
+}
+
+func TestQuery(t *testing.T) {
+	doc, err := Parse(strings.NewReader(BooksExample))
+	if err != nil {
+		t.Fatal(err)
+	}
+	q := "/store/bicycle"
+	n := FindOne(doc, q)
+	if n == nil {
+		t.Fatal("should matched 1 but got nil")
+	}
+	q = "/store/bicycle/color"
+	n = FindOne(doc, q)
+	if n == nil {
+		t.Fatal("should matched 1 but got nil")
+	}
+	if n.Data != "color" {
+		t.Fatalf("expected data is color, but got %s", n.Data)
+	}
+}
+
+func TestQueryWhere(t *testing.T) {
+	doc, err := Parse(strings.NewReader(BooksExample))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// for number
+	q := "//*[price<=12.99]"
+	list := Find(doc, q)
+
+	if got, expected := len(list), 3; got != expected {
+		t.Fatalf("%s expected %d objects, but got %d", q, expected, got)
+	}
+
+	// for string
+	q = "//*/isbn[text()='0-553-21311-3']"
+	if n := FindOne(doc, q); n == nil {
+		t.Fatal("should matched 1 but got nil")
+	} else if n.Data != "isbn" {
+		t.Fatalf("should matched `isbm` but got %s", n.Data)
+	}
+}
+
+var BooksExample string = `{
+	"store": {
+	  "book": [
+		{
+		  "category": "reference",
+		  "author": "Nigel Rees",
+		  "title": "Sayings of the Century",
+		  "price": 8.95
+		},
+		{
+		  "category": "fiction",
+		  "author": "Evelyn Waugh",
+		  "title": "Sword of Honour",
+		  "price": 12.99
+		},
+		{
+		  "category": "fiction",
+		  "author": "Herman Melville",
+		  "title": "Moby Dick",
+		  "isbn": "0-553-21311-3",
+		  "price": 8.99
+		},
+		{
+		  "category": "fiction",
+		  "author": "J. R. R. Tolkien",
+		  "title": "The Lord of the Rings",
+		  "isbn": "0-395-19395-8",
+		  "price": 22.99
+		}
+	  ],
+	  "bicycle": {
+		"color": "red",
+		"price": 19.95
+	  }
+	},
+	"expensive": 10
+  }
+`