Java基礎(chǔ)之FastJson詳解

更新時(shí)間：2021年05月17日 16:59:57 作者：喜羊羊love紅太狼

今天給大家復(fù)習(xí)Java基礎(chǔ)FastJson,文中有非常詳細(xì)的代碼示例,對(duì)正在學(xué)習(xí)java的小伙伴們有很好地幫助,需要的朋友可以參考下

一、fastJson將json格式字符串轉(zhuǎn)化成List集合
二、fastJson將json格式字符串轉(zhuǎn)化成對(duì)象
三、FastJson將對(duì)象或集合轉(zhuǎn)化成json格式字符串
四、FastJson將json格式字符串轉(zhuǎn)化成json對(duì)象
五、FastJson將json格式字符串轉(zhuǎn)化成json數(shù)組
六、FastJson將java對(duì)象轉(zhuǎn)化成json對(duì)象

一、fastJson將json格式字符串轉(zhuǎn)化成List集合

注：json格式字符串必須符合數(shù)組型格式如[{"a":a},{"b":b}]

場景一：前端向后臺(tái)傳遞數(shù)組格式的json字符串，如何轉(zhuǎn)化成List集合

List<AccountBean> readJson2List =JSON.parseArray(json, AccountBean.class)注意這里是Bean.class而不是List.class

	@Test
	public void readJson2ListBean() {
		String json = "[{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}]";
		List<AccountBean> readJson2List =JSON.parseArray(json, AccountBean.class);
		//輸出測試
		JsonUtils.beanToJson(readJson2List);
	}

場景二：前端向后臺(tái)傳遞數(shù)組格式的json字符串，如何轉(zhuǎn)化成List<HashMap<String,Object>>集合

	@Test
	public void readJson2ListMap() {
		String json = "[{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}]";
		List<HashMap> readJson2List =JSON.parseArray(json,HashMap.class);
		//輸出測試
		JsonUtils.beanToJson(readJson2List);
	}

二、fastJson將json格式字符串轉(zhuǎn)化成對(duì)象

場景一：前端向后臺(tái)傳遞數(shù)組格式的json字符轉(zhuǎn)化成Bean對(duì)象

@Test
	public void readJson2Bean() {
		String json = "{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"}";
		AccountBean accountBean  =JSON.parseObject(json,AccountBean.class);
		//輸出測試
		JsonUtils.beanToJson(accountBean);
	}

場景二：前端向后臺(tái)傳遞數(shù)組格式的json字符串Map<String,Object>集合

@Test
	public void readJson2Map() {
		String json = "{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"}";
		HashMap<String,Object> accountBean  =JSON.parseObject(json,Map.class);
		//輸出測試
		JsonUtils.beanToJson(accountBean);
	}

測試：

三、FastJson將對(duì)象或集合轉(zhuǎn)化成json格式字符串

@Test
	public void beanAndCollectionTOJson() {
		AccountBean	bean = new AccountBean();
		bean.setAddress("china-Guangzhou");
		bean.setEmail("hoojo_@126.com");
		bean.setId(1);
		bean.setName("hoojo");
		String json  = JSON.toJSONString(bean);
		System.out.println(json);
	}

四、FastJson將json格式字符串轉(zhuǎn)化成json對(duì)象

@Test
	public void jsonStringTOJsonBean() {
		String json = "{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"}";
		JSONObject parse = (JSONObject) JSON.parse(json);
		String address = (String) parse.get("address");
		System.out.println("輸出address=="+address);
	}

五、FastJson將json格式字符串轉(zhuǎn)化成json數(shù)組

	@Test
	public void jsonString2JsonArray() {
		String json = "[{\"address\": \"address2\",\"name\":\"haha2\",\"id\":2,\"email\":\"email2\"},{\"address\":\"address\",\"name\":\"haha\",\"id\":1,\"email\":\"email\"}]";
		JSONArray parseArray = JSON.parseArray(json);
		//輸出測試
		JsonUtils.beanToJson(parseArray.get(0));
	}

六、FastJson將java對(duì)象轉(zhuǎn)化成json對(duì)象

@Test
	public void beanAndCollectionTOJsonBean() {
		AccountBean	bean = new AccountBean();
		bean.setAddress("china-Guangzhou");
		bean.setEmail("hoojo_@126.com");
		bean.setId(1);
		bean.setName("hoojo");
		JSONObject json  = (JSONObject) JSON.toJSON(bean);
		json.get("address");
		System.out.println(json);
	}