我正在春季启动中编写REST服务。我想让我的DTO课程的一些字段作为可选的获取器访问。这是一个例子。
@JsonInclude(Include.NON_NULL)
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.EXISTING_PROPERTY, property = "profileType", visible = true, defaultImpl = InvalidUserDTO.class)
@JsonSubTypes({ @JsonSubTypes.Type(value = ClientDTO.class, name = "CLIENT"), @JsonSubTypes.Type(value = DriverDTO.class, name = "DRIVER") })
public abstract class UserDTO {
private String password;
private Optional<String> email;
使用这种方法,在我的休息回复中,我得到了类似email: {"present" : true}
的东西,而不是电子邮件的真实价值。
为了解决这个问题,我尝试将JDK8模块依赖项添加到classPath。
但是,这仅在尝试在使用选项的端点上调用我的服务时仅引起以下错误:
{"message":"Internal Server Error","details":"Handler dispatch failed; nested exception is java.lang.AbstractMethodError:
com.fasterxml.jackson.databind.ser.std.ReferenceTypeSerializer.withResolved(Lcom/fasterxml/jackson/databind/BeanProperty;Lcom/fasterxml/jackson/databind/jsontype/TypeSerializer;
Lcom/fasterxml/jackson/databind/JsonSerializer;Lcom/fasterxml/jackson/databind/util/NameTransformer;Lcom/fasterxml/jackson/annotation/JsonInclude$Include;)
Lcom/fasterxml/jackson/databind/ser/std/ReferenceTypeSerializer;"}
我缺少什么吗?为什么会发生?
这是ObjectMapper配置:
@SpringBootApplication
public class MainApplication extends SpringBootServletInitializer {
@Autowired
void configureObjectMapper(final ObjectMapper mapper) {
mapper
.registerModule(new ParameterNamesModule())
.registerModule(new Jdk8Module());
}
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
servletContext.setInitParameter("webAppRootKey", "newfacesBackend.root");
servletContext.setInitParameter("isLog4jAutoInitializationDisabled", "true");
super.onStartup(servletContext);
}
public static void main(String[] args) throws Exception {
SpringApplication.run(MainApplication.class, args);
}
}
gradle依赖性:
buildscript {
dependencies {
classpath("org.springframework.boot:spring-boot-gradle-plugin:1.5.4.RELEASE")
}
}
apply plugin: 'com.github.ben-manes.versions'
apply plugin: 'maven-publish'
apply plugin: 'org.springframework.boot'
configurations {
compile.exclude group:'ch.qos.logback'
}
dependencies {
compile("org.springframework.boot:spring-boot-starter-actuator")
compile("org.springframework.boot:spring-boot-starter-web")
compile("com.fasterxml.jackson.datatype:jackson-datatype-jdk8:2.9.4")
compile("com.fasterxml.jackson.module:jackson-module-parameter-names:2.9.4")
您应该用映射器注册JDK8模块,例如:
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new Jdk8Module());
或,
您可以通过将以下内容添加到您的主要春季启动应用程序类中:
@Autowired
void configureObjectMapper(final ObjectMapper mapper) {
mapper.registerModule(new ParameterNamesModule())
.registerModule(new Jdk8Module());
}
ParameterNamesModule
的依赖性是:
<dependency>
<groupId>com.fasterxml.jackson.module</groupId>
<artifactId>jackson-module-parameter-names</artifactId>
</dependency>
有这个问题,结果我有不相容的依赖项
您有依赖性org.springframework.boot:spring-boot-starter-actuator:1.5.4.RELEASE
:
buildscript {
dependencies {
classpath("org.springframework.boot:spring-boot-gradle-plugin:1.5.4.RELEASE")
}
}
...
dependencies {
compile("org.springframework.boot:spring-boot-starter-actuator")
}
有自己的依赖性com.fasterxml.jackson.core:jackson-databind:2.8.8
并且与您提供的另一个fasterxml依赖性不兼容:
compile("com.fasterxml.jackson.datatype:jackson-datatype-jdk8:2.9.4")
解决方案
只是降级Jackson-Datatype-jdk8版本:
compile("com.fasterxml.jackson.datatype:jackson-datatype-jdk8:2.8.8")
删除configureObjectMapper
并尝试以下操作:
@Configuration
public class ObjectMapperConfig
@Bean
@Primary
public ObjectMapper objectMapper(Jackson2ObjectMapperBuilder builder) {
ObjectMapper objectMapper = builder.build();
objectMapper.registerModule(new Jdk8Module());
return objectMapper;
}
}