标签：体验 api 步骤 ast pen ret div add 解析json数据
JSON解析之FastJson(阿里巴巴解析开源)
特点:
Fastjson是一个Java语言编写的高性能功能完善的JSON库，它采用的
是一种"假定有序快速匹配"的算法，把JSON Parse的性能提升到极致，
是目前Java语言中最快的JSON库。
1.将json格式{}转换为Java对象
API:
<T> T parseObject(String json,Class<T> classOfT);
步骤:
1.导入fastjson的jar包
2.JSON调用parseObject()方法，获取转换后的java对象
例如:
ShopInfo shopInfo=JSON.parseObject(json,ShopInfo.class)；
代码:
ShopInfo的类:
public class ShopInfo {
private int id;
private String name;
private double price;
private String imagePath;
public ShopInfo() {
}
public ShopInfo(int id, String name, double price, String imagePath) {
this.id = id;
this.name = name;
this.price = price;
this.imagePath = imagePath;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getPrice() {
return price;
}
public void setPrice(double price) {
this.price = price;
}
public String getImagePath() {
return imagePath;
}
public void setImagePath(String imagePath) {
this.imagePath = imagePath;
}
@Override
public String toString() {
return "ShopInfo{" +
"id=" + id +
", name=‘" + name + ‘\‘‘ +
", price=" + price +
", imagePath=‘" + imagePath + ‘\‘‘ +
‘}‘;
}
}
解析json数据:
public class One {
public static void main(String[] args) {
String json = "{\n" +
" \"id\":1,\n" +
" \"name\":\"豆瓣\",\n" +
" \"price\":12.3,\n" +
" \"imagePath\":\"http://www.douban.com\"\n" +
"}";
ShopInfo shopInfo = JSON.parseObject(json, ShopInfo.class);
System.out.println(shopInfo.toString());
}
}
2.将json格式的字符串[]转换为Java对象的List
API:
List<T> parseArray(String json,Class<T> classOft);
步骤:
1.导入fastjson的jar包
2.JSON调用parseArray()方法，获取转换后的java集合
例如:
List<ShopInfo> shopInfos = JSON.parseArray(json,ShopInfo.class);
代码:
public class Two {
public static void main(String[] args) {
String json = "[\n" +
" {\n" +
" \"id\":1,\n" +
" \"imagePath\":\"http://www.baidu.com\",\n" +
" \"name\":\"大虾1\",\n" +
" \"price\":12.3\n" +
" },\n" +
" {\n" +
" \"id\":2,\n" +
" \"imagePath\":\"http://www.douban.com\",\n" +
" \"name\":\"大虾2\",\n" +
" \"price\":12.5\n" +
" }\n" +
"]";
List<ShopInfo> shopInfos = JSON.parseArray(json, ShopInfo.class);
System.out.println(shopInfos);
}
}
3.将java对象转换为json字符串{}
API:
String toJSONString(Object object);
步骤:
1.导入fastjson的jar包
2.JSON调用toJSONString()方法，获取转换后的json数据
例如:
ShopInfo shopInfo = new ShopInfo(1,"鲍鱼",255.5,"baoyu");
String json = JSON.toJSONString(shopInfo);
代码:
public class Three {
public static void main(String[] args) {
ShopInfo shopInfo = new ShopInfo(1, "哔哩哔哩", 125.5, "www.blibli.com");
String json = JSON.toJSONString(shopInfo);
System.out.println(json);
}
}
4.将Java对象的List转换为json的字符串[]
API:
String toJSONString(Object object);
步骤:
1.导入fastjson的jar包
2.JSON调用toJSONString()方法，获取转换后的json数据
例如:
List<ShopInfo> shops = new ArrayList<>();
ShopInfo shopInfo1 = new ShopInfo(1, "哔哩哔哩", 255.5, "www.blibli.com");
ShopInfo shopInfo2 = new ShopInfo(1, "豆瓣", 255.5, "www.douban.com");
ShopInfo shopInfo3 = new ShopInfo(1, "知乎", 255.5, "www.zhihu.com");
shops.add(shopInfo1);
shops.add(shopInfo2);
shops.add(shopInfo3);
String json = JSON.toJSONString(shops);
代码:
public class Four {
public static void main(String[] args) {
ShopInfo shopInfo1 = new ShopInfo(1, "哔哩哔哩", 255.5, "www.blibli.com");
ShopInfo shopInfo2 = new ShopInfo(1, "豆瓣", 255.5, "www.douban.com");
ShopInfo shopInfo3 = new ShopInfo(1, "知乎", 255.5, "www.zhihu.com");
List<ShopInfo> list = new ArrayList<ShopInfo>();
list.add(shopInfo1);
list.add(shopInfo2);
list.add(shopInfo3);
String json = JSON.toJSONString(list);
System.out.println(json);
}
}
最后补一下fastjson在maven中的地址:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.32</version>
</dependency>
最后，再说一句，和本节内容无关的事：
翟哥，我错了，我真的错了，原谅我吧！
标签：体验 api 步骤 ast pen ret div add 解析json数据
原文地址：http://www.cnblogs.com/wnbahmbb/p/7019995.html
