I want to transfer as much light data as possible in one transfer, so I used List<Object> to package light data, but I had trouble deserializing with Jackson.,java,json,serialization,jackson,deserialization"/>

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I want to transfer as much light data as possible in one transfer, so I used List<Object> to package light data, but I had trouble deserializing with Jackson.

java - 如何反序列化列表 with jackson,each object has its own type?

I want to transfer as much light data as possible in one transfer, so I used List<Object> to package light data, but I had trouble deserializing with Jackson.

问题描述

I want to transfer as much light data as possible in one transfer, so I used List<Object> to package light data, but I had trouble deserializing with Jackson. The sample code looks like the following：</p> 

List<Object>list=new LinkedList<>();

list.add(new Teacher(name,id));
list.add(new Student(name,id));
ObjectMapper objectmapper=new ObjectMapper();
String json=objectMapper.writeValueAsString(list);
objectMapper.readValue(json, new TypeReference<List<Object>>(){});

expected :

Teacher teacher=(Teacher)list.removeFirst();

Student student=(Student)list.removeFirst();

But in fact, Jackson made the object to LinkedHashMap so I can't achieve it. Does Jackson have any way to achieve this effect?

Seaborn: ValueError: No for palette='jet'

Running the following example from seaborn docs with argument palette='jet'

import seaborn as sns
tips = sns.load_dataset("tips")
ax = sns.boxplot(x="day", y="total_bill", hue="smoker", data=tips, palette='jet')

got the following error

    172         elif palette.lower() == "jet":
    173             # Paternalism
--> 174             raise ValueError("No.")
    175 
    176         elif palette.startswith("ch:"):

ValueError: No.

What's the reason for this error with the jet color palette ? I wonder if the error message can be more specific cause matplotlib docs states the following

The often-used jet colormap is included in this set of colormaps. We can see that the values vary widely throughout the colormap, making it a poor choice for representing data for viewers to see perceptually.

标签： javajsonserializationjacksondeserialization

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