JAVA中JSON序列化和反序列化
JAVA中JSON序列化和反序列化
- 1 FASTJSON的序列化和反序列化
-
- 1.1 主函数
- 1.2 自定义对象
- 2 GSON序列化和反序列化
-
- 2.1 主函数
- 2.2 自定义对象
- 总结
不同包序列化和反序列化的方式不同，其修改对象属性名称的注释也不相同。
1 FASTJSON的序列化和反序列化
1.1 主函数
public class testJsonMy {
public static void main(String[] args) {
String jsonString = "{'id':'1','name':'西游记','prince':36}";
String jsonStringNew = "{\"code\":\"200\",\"ok\":\"true\",\"data\":[{\"id\":\"3\",\"name\":\"水浒传\",\"prince\":35}]}";
//1.1使用FastJson获取json字符串中对应对象值
System.out.println("1.1使用FastJson获取json字符串中对应对象值");
System.out.println("JSONObject parseObject str: " +jsonString);
JSONObject jsonObject = JSONObject.parseObject(jsonString);
String id = jsonObject.getString("id");
String name = jsonObject.getString("name");
String prince = jsonObject.getString("prince");
System.out.println("JSONObject parseObject id: " + id + ", name: " + name + ", prince: " + prince);
String nameNew = JSONObject.parseObject(jsonString).getString("name");
System.out.println("JSONObject parseObject nameNew: " + nameNew);
//1.2使用FastJson转化成自定义类对象, 再获取json字符串中对应对象值
System.out.println("\n1.2使用FastJson转化成自定义类对象, 再获取json字符串中对应对象值");
Book book = JSONObject.parseObject(jsonString, Book.class);
System.out.println("JSONObject parseObject book: " + book);
System.out.println("JSONObject parseObject book name: " + book.getBookName());
//1.3使用FastJson转化成Map集合, 再获取json字符串中对应对象值
System.out.println("\n1.3使用FastJson转化成Map集合, 再获取json字符串中对应对象值");
Map map = JSONObject.parseObject(jsonString, Map.class);
System.out.println("JSONObject parseObject map: " + map);
System.out.println("JSONObject parseObject map name: " + map.get("name"));
//1.4使用FastJson将对象序列化为json格式的字符串和将字符串反序列化为自定义对象
System.out.println("\n1.4使用FastJson将对象序列化为json格式的字符串和将字符串反序列化为自定义对象");
Book book1 = new Book("2", "三国演义", 40);
String book1JsonString = JSON.toJSONString(book1);
System.out.println("JSON toJSONString book1JsonString: " + book1JsonString);
Book book2 = JSONObject.parseObject(book1JsonString, Book.class);
System.out.println("JSONObject parseObject book2: " + book2);
//1.5 获取data中内容
System.out.println("\n1.5 获取data中内容");
JSONArray data = JSONObject.parseObject(jsonStringNew).getJSONArray("data");
System.out.println("JSONObject parseObject data: " + data);
JSONObject jsonObjectData0 = (JSONObject) data.get(0);
System.out.println("JSONObject parseObject jsonObjectData0: " + jsonObjectData0);
String name1 = jsonObjectData0.getString("name");
System.out.println(name1);
}
}
1.2 自定义对象
使用@JSONField修改序列化和反序列化属性名称。
class Book {
private String id;
@JSONField(name = "name") // fastJson
private String bookName;
private int prince;
public Book() {
}
public Book(String id, String bookName, int prince) {
this.id = id;
this.bookName = bookName;
this.prince = prince;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getBookName() {
return bookName;
}
public void setBookName(String bookName) {
this.bookName = bookName;
}
public int getPrince() {
return prince;
}
public void setPrince(int prince) {
this.prince = prince;
}
@Override
public String toString() {
return "Book{" +
"id='" + id + '\'' +
", bookName='" + bookName + '\'' +
", prince=" + prince +
'}';
}
}
2 GSON序列化和反序列化
2.1 主函数
public class testGsonMy {
private static Gson gson = new GsonBuilder().registerTypeAdapter(Date.class, new DateTypeAdapter()).serializeNulls().create();
public static void main(String[] args) {
String jsonString = "{'id':'1','name':'西游记','prince':36}";
String jsonStringNew = "{\"code\":\"200\",\"ok\":\"true\",\"data\":[{\"id\":\"3\",\"name\":\"水浒传\",\"prince\":35}]}";
System.out.println("\n---------------------------GSON---------------------------");
System.out.println("gson str: " + jsonString);
System.out.println("\n2.1使用GSON转化成自定义类对象, 再获取json字符串中对应对象值");
// 2.1使用GSON转化成自定义类对象, 再获取json字符串中对应对象值
BookGson bookGson = gson.fromJson(jsonString, BookGson.class);
System.out.println("gson fromJson bookGson: " + bookGson);
System.out.println("gson fromJson bookGson name: " + bookGson.getBookName());
// 2.2使用GSON转化成Map集合, 再获取json字符串中对应对象值
System.out.println("\n2.2使用GSON转化成Map集合, 再获取json字符串中对应对象值");
Map bookGsonMap = gson.fromJson(jsonString, Map.class);
System.out.println("gson fromJson bookGson Map: " + bookGsonMap);
System.out.println("gson fromJson bookGson Map name: " + bookGsonMap.get("name"));
//2.3使用GSON将对象序列化为json格式的字符串和将字符串反序列化为自定义对象
System.out.println("\n2.3使用GSON将对象序列化为json格式的字符串和将字符串反序列化为自定义对象");
BookGson bookGson1 = new BookGson("3", "水浒传", 42);
String book1GsonString = gson.toJson(bookGson1);
System.out.println("gson toString book1GsonString: " + book1GsonString);
BookGson bookGsonStruct = gson.fromJson(book1GsonString, BookGson.class);
System.out.println("gson fromJson bookGsonStruct: " + bookGsonStruct);
//2.4 使用GSON获取data中内容
//2.4.1 序列化为Map集合, 再获取data中内容
System.out.println("\n2.4.1 序列化为Map集合, 再获取data中内容");
Map resultMap = gson.fromJson(jsonStringNew, Map.class);
System.out.println("gson fromJson resultMap: " + resultMap);
ArrayList<Map> bookGsons = (ArrayList<Map>) resultMap.get("data");
System.out.println("bookGsons: " + bookGsons);
Map bookGsonNew = bookGsons.get(0);
System.out.println("bookGsonNew: " + bookGsonNew);
System.out.println("bookGsonNew.name: " + bookGsonNew.get("name"));
//2.4.2 反序列化为自定义对象, 再获取data中内容
System.out.println("\n2.4.2 反序列化为自定义对象, 再获取data中内容");
ResultBook resultBook = gson.fromJson(jsonStringNew, ResultBook.class);
System.out.println("gson fromJson str: " + jsonStringNew);
System.out.println("gson fromJson resultBook: " + resultBook);
System.out.println("gson fromJson bookGsonList: " + resultBook.getBookGsonList());
System.out.println("gson fromJson bookGsonList[0]: " + resultBook.getBookGsonList().get(0));
System.out.println("gson fromJson bookGsonList[0].name: " + resultBook.getBookGsonList().get(0).getBookName());
}
}
2.2 自定义对象
使用@SerializedName修改对象中属性名称
class ResultBook {
private String code;
private boolean ok;
@SerializedName("data") // gson
private List<BookGson> bookGsonList;
public ResultBook() {
}
public ResultBook(String code, boolean ok, List<BookGson> bookGsonList) {
this.code = code;
this.ok = ok;
this.bookGsonList = bookGsonList;
}
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public boolean isOk() {
return ok;
}
public void setOk(boolean ok) {
this.ok = ok;
}
public List<BookGson> getBookGsonList() {
return bookGsonList;
}
public void setBookGsonList(List<BookGson> bookGsonList) {
this.bookGsonList = bookGsonList;
}
@Override
public String toString() {
return "ResultBook{" +
"code='" + code + '\'' +
", ok=" + ok +
", bookGsonList=" + bookGsonList +
'}';
}
}
class BookGson {
private String id;
@Expose
@SerializedName("name") // gson
private String bookName;
private int prince;
public BookGson() {
}
public BookGson(String id, String bookName, int prince) {
this.id = id;
this.bookName = bookName;
this.prince = prince;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getBookName() {
return bookName;
}
public void setBookName(String bookName) {
this.bookName = bookName;
}
public int getPrince() {
return prince;
}
public void setPrince(int prince) {
this.prince = prince;
}
@Override
public String toString() {
return "Book{" +
"id='" + id + '\'' +
", bookName='" + bookName + '\'' +
", prince=" + prince +
'}';
}
}
总结
以上就是JSON中序列化和反序列化的主要内容。在序列化和反序列化时可灵活使用注释修改参数名称，便于对参数处理；除此之外，在反序列化时即可以使用Map来获取内容，也可以自定义对象获取内容。