将常量numpy数组值分配给pandas dataframe列(Assign constant numpy array value to pandas dataframe column)

 您可以使用以下代码编写带有Java代码的Custom Serializer和De-Serializer： 
 
class CustomSerializer extends JsonSerializer<ARow> {
@Override
public Class<ARow> handledType() {
    return ARow.class;
}

public void serialize(ARow value, JsonGenerator jgen, SerializerProvider provider)
        throws IOException, JsonProcessingException {
    jgen.writeStartObject();
    jgen.writeStringField("ounc", value.ounces.toLowerCase()); //Do this for all of your relevant properties..
    jgen.writeEndObject();
}
 
 } 
 
 并向杰克逊注册此自定义序列化器： 
 
ObjectMapper m = new ObjectMapper();
SimpleModule testModule = new SimpleModule("MyModule", new Version(1, 0, 0, null));
testModule.addSerializer(new CustomSerializer());
m.registerModule(testModule);
 
 要使用Spring的MappingJacksonJsonView您需要扩展自己的ObjectMapper 
 
public class MyCustomObjectMapper extends ObjectMapper {
    public MyCustomObjectMapper() {
        SimpleModule module = new SimpleModule("My Module", new Version(1, 0, 0, "SNAPSHOT"));
        module.addSerializer(new CustomSerializer());
        module.addSerializer(new CustomSerializer2());
        // etc
        this.registerModule(module);
    }
}
 
 为它创建一个bean 
 
<bean id="myCustomObjectMapper" class="com.foo.proj.objectmapper.MyCustomObjectMapper"/>
 
 并将其注入MappingJacksonJsonView 
 
<bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView">
    <property name="objectMapper" ref="myCustomObjectMapper"/>
</bean>

You can write a Custom Serializer and De-Serializer, with Java code, along these lines:
 
class CustomSerializer extends JsonSerializer<ARow> {
@Override
public Class<ARow> handledType() {
    return ARow.class;
}

public void serialize(ARow value, JsonGenerator jgen, SerializerProvider provider)
        throws IOException, JsonProcessingException {
    jgen.writeStartObject();
    jgen.writeStringField("ounc", value.ounces.toLowerCase()); //Do this for all of your relevant properties..
    jgen.writeEndObject();
}
 
}
 
and to register this Custom Serializer with Jackson:
 
ObjectMapper m = new ObjectMapper();
SimpleModule testModule = new SimpleModule("MyModule", new Version(1, 0, 0, null));
testModule.addSerializer(new CustomSerializer());
m.registerModule(testModule);
 
To set this up with Spring's MappingJacksonJsonView you will need to extend your own ObjectMapper
 
public class MyCustomObjectMapper extends ObjectMapper {
    public MyCustomObjectMapper() {
        SimpleModule module = new SimpleModule("My Module", new Version(1, 0, 0, "SNAPSHOT"));
        module.addSerializer(new CustomSerializer());
        module.addSerializer(new CustomSerializer2());
        // etc
        this.registerModule(module);
    }
}
 
Create a bean for it
 
<bean id="myCustomObjectMapper" class="com.foo.proj.objectmapper.MyCustomObjectMapper"/>
 
And inject it into your MappingJacksonJsonView
 
<bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView">
    <property name="objectMapper" ref="myCustomObjectMapper"/>
</bean>