在实际项目中，我们需要封装一个统一的 Json返回结构存储返回信息。
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.jf</groupId> <artifactId>JsonFormat</artifactId> <version>0.0.1-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.0.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <properties> <!-- 声明项目配置依赖编码格式为 utf-8 --> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <fastjson.version>1.2.24</fastjson.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> <dependency> <groupId>org.webjars</groupId> <artifactId>jquery</artifactId> <version>3.3.1</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <artifactId>maven-compiler-plugin</artifactId> <configuration> <source>1.8</source> <target>1.8</target> </configuration> </plugin> </plugins> </build> </project>
package com.tszr.json.format.user; public class User { private int id; private String name; private String password; public User(int id, String name, String password) { // TODO Auto-generated constructor stub this.id = id; this.name = name; this.password = password; } 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 String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
package com.tszr.json.format.jsonresult; public class JsonResult<T> { private T data; public T getData() { return data; } public void setData(T data) { this.data = data; } public String getCode() { return code; } public void setCode(String code) { this.code = code; } public String getMsg() { return msg; } public void setMsg(String msg) { this.msg = msg; } private String code; private String msg; /** * 若没有数据返回，默认状态码为0，提示信息为：操作成功！ */ public JsonResult() { this.code = "0"; this.msg = "操作成功！"; } /** * 若没有数据返回，可以人为指定状态码和提示信息 * * @param code * @param msg */ public JsonResult(String code, String msg) { this.code = code; this.msg = msg; } /** * 有数据返回时，状态码为0，默认提示信息为：操作成功！ * * @param data */ public JsonResult(T data) { this.data = data; this.code = "0"; this.msg = "操作成功！"; } /** * 有数据返回，状态码为0，人为指定提示信息 * * @param data * @param msg */ public JsonResult(T data, String msg) { this.data = data; this.code = "0"; this.msg = msg; } }
package com.tszr.json.format.controller; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import com.tszr.json.format.jsonresult.JsonResult; import com.tszr.json.format.user.User; @RestController @RequestMapping("/jsonresult") public class UserController { @RequestMapping("/user") public JsonResult<User> getUser() { User user = new User(10, "贝西", "11"); return new JsonResult<>(user); } @RequestMapping("/list") public JsonResult<List<User>> getUserList() { List<User> userlist = new ArrayList<>(); User user1 = new User(1, "吴裕雄", "123456"); User user2 = new User(1, "天生自然", "123456"); userlist.add(user1); userlist.add(user2); return new JsonResult<>(userlist, "获取用户列表成功"); } @RequestMapping("/map") public JsonResult<Map<String, Object>> getMap() { Map<String, Object> map = new HashMap<>(3); User user3 = new User(1, "天生自然", null); map.put("作者信息", user3); map.put("博客地址", "https://www.cnblogs.com/tszr"); map.put("公众号", null); map.put("B站", null); return new JsonResult<>(map); } }
package com.tszr.json.format.configuration; import java.io.IOException; import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.Primary; import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder; import com.fasterxml.jackson.core.JsonGenerator; import com.fasterxml.jackson.databind.JsonSerializer; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.SerializerProvider; @Configuration public class JacksonConfig { @Bean @Primary @ConditionalOnMissingBean(ObjectMapper.class) public ObjectMapper jacksonObjectMapper(Jackson2ObjectMapperBuilder builder) { ObjectMapper objectMapper = builder.createXmlMapper(false).build(); objectMapper.getSerializerProvider().setNullValueSerializer(new JsonSerializer<Object>() { @Override public void serialize(Object o, JsonGenerator jsonGenerator, SerializerProvider serializerProvider) throws IOException { jsonGenerator.writeString(""); } }); return objectMapper; } }
package com.tszr.json.format; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class JsonFormatApplication { public static void main(String[] args) { SpringApplication.run(JsonFormatApplication.class, args); } }
