FastJson 基础教程
发布时间：2020-12-16 18:48:19 所属栏目：百科 来源：网络整理
导读：介绍 Fastjson是一个Java语言编写的高性能功能完善的JSON库。它采用一种“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。Fastjson接口简单易用，已经被广泛使用在缓存序列化、协议交互、Web输出、Android客户端等
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介绍 Fastjson是一个Java语言编写的高性能功能完善的JSON库。它采用一种“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。Fastjson接口简单易用，已经被广泛使用在缓存序列化、协议交互、Web输出、Android客户端等多种应用场景。 教程 maven依赖 <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.24</version> </dependency> package com.zzg.entity; import java.io.Serializable; public class Address implements Serializable { /** * */ private static final long serialVersionUID = 1L; private int id; private String provice; private String city; private String area; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getProvice() { return provice; } public void setProvice(String provice) { this.provice = provice; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getArea() { return area; } public void setArea(String area) { this.area = area; } } package com.zzg.entity; import java.io.Serializable; import java.util.List; public class User implements Serializable { /** * */ private static final long serialVersionUID = 1L; private int id; private String name; private int sex; private List<Address> list; 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 int getSex() { return sex; } public void setSex(int sex) { this.sex = sex; } public List<Address> getList() { return list; } public void setList(List<Address> list) { this.list = list; } } 1、序列化 主要通过 JSON.toJSONString方法将Bean转换为json。 //通过 JSON.toJSONString方法将Bean转换为json。 User user =new User(); user.setId(1); user.setName("周志刚"); user.setSex(1); List<Address> address=new ArrayList<Address>(); Address one = new Address(); one.setArea("开福区"); one.setCity("长沙市"); one.setId(1); one.setProvice("湖南省"); address.add(one); Address two = new Address(); two.setArea("天河区"); two.setCity("广州市"); two.setId(1); two.setProvice("广东省"); address.add(two); user.setList(address); System.out.println("结果："+JSON.toJSONString(user)); 结果如下： {"id":1,"list":[{"area":"开福区","city":"长沙市","id":1,"provice":"湖南省"},{"area":"天河区","city":"广州市","provice":"广东省"}],"name":"周志刚","sex":1} 2、反序列化 主要通过JSON.parSEObject方法将json转换为Bean对象，如下： //通过JSON.parSEObject方法将json转换为Bean对象 String json = "{"id":1,"list":[{"area":"开福区","city":"长沙市","id":1,"provice":"湖南省"},{"area":"天河区","city":"广州市","provice":"广东省"}],"name":"周志刚","sex":1}"; User u = JSON.parSEObject(json,User.class); System.out.println("用户名次:"+u.getName()); 结果如下： 用户名次:周志刚 3、JSONField 介绍 package com.alibaba.fastjson.annotation; public @interface JSONField { // 配置序列化和反序列化的顺序，1.1.42版本之后才支持 int ordinal() default 0; // 指定字段的名称 String name() default ""; // 指定字段的格式，对日期格式有用 String format() default ""; // 是否序列化 boolean serialize() default true; // 是否反序列化 boolean deserialize() default true; } 3.1 指定序列化名称 指定User的list属性在序列化时变成addr_list，如下： package com.zzg.entity; import java.io.Serializable; import java.util.List; import com.alibaba.fastjson.annotation.JSONField; public class User implements Serializable { /** * */ private static final long serialVersionUID = 1L; private int id; private String name; private int sex; @JSONField(name="addr_list") private List<Address> list; 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 int getSex() { return sex; } public void setSex(int sex) { this.sex = sex; } public List<Address> getList() { return list; } public void setList(List<Address> list) { this.list = list; } } 输出结果： {"addr_list":[{"area":"开福区","sex":1} 3.2 使用serialize/deserialize指定字段不序列化 控制sex属性不序列化，如下： package com.zzg.entity; import java.io.Serializable; import java.util.List; import com.alibaba.fastjson.annotation.JSONField; public class User implements Serializable { /** * */ private static final long serialVersionUID = 1L; private int id; private String name; @JSONField(serialize=false) private int sex; @JSONField(name="addr_list") private List<Address> list; 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 int getSex() { return sex; } public void setSex(int sex) { this.sex = sex; } public List<Address> getList() { return list; } public void setList(List<Address> list) { this.list = list; } } 结果输出： {"addr_list":[{"area":"开福区","name":"周志刚"} 3.3 使用ordinal指定字段的顺序 package com.zzg.entity; import java.io.Serializable; import com.alibaba.fastjson.annotation.JSONField; public class Address implements Serializable { /** * */ private static final long serialVersionUID = 1L; @JSONField(ordinal = 4) private int id; @JSONField(ordinal = 1) private String provice; @JSONField(ordinal = 2) private String city; @JSONField(ordinal = 3) private String area; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getProvice() { return provice; } public void setProvice(String provice) { this.provice = provice; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getArea() { return area; } public void setArea(String area) { this.area = area; } } 输出结果： {"addr_list":[{"provice":"湖南省","area":"开福区","id":1},{"provice":"广东省","area":"天河区","id":1}],"name":"周志刚"} 参考资料： https://github.com/alibaba/fastjson/wiki/JSONField （编辑：李大同） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |