使用Jackson将Json文件映射到POJO所需的@JsonProperty(@JsonProperty Required for Mapping Json File to POJO Using Jackson)

 我有一个Java类文件，如下所示： 
 
public class ToBeMapped {
     String value1;
     int value 2;
}
 
 然后我有一个名为“test.json”的JSON文件，如下所示： 
 
{
    "value1": "hellow world",
    "value2": 12345
}
 
 然后我尝试将JSON文件映射到另一个Java文件中的“TobeMapped”对象： 
 
public class Testing {
    public void justTesting() throws IOException {
        ToBeMapped temp = new ObjectMapper().readValue(new File("path/to/test.json"), ToBeMapped.class);
    }
}
 
 这会给我以下错误： 
 
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "value1" ...
 
 如果我在每个类变量之前添加@JsonProperty ，我可以将JSON文件映射到POJO而没有任何错误。 
 
public class ToBeMapped {

     @JsonProperty
     String value1;

     @JsonProperty
     int value 2;
}
 
 为了让Jackson的映射器将JSON文件/流映射到对象，我是否必须将此标头添加到每个类变量中？ 或者我在代码中遗漏了一些东西？ 
 
 谢谢。 

I have a Java class file that looks like following:
 
public class ToBeMapped {
     String value1;
     int value 2;
}
 
Then I have a JSON file, named "test.json", looks like following:
 
{
    "value1": "hellow world",
    "value2": 12345
}
 
Then I try to map the JSON file to "TobeMapped" object in another Java file:
 
public class Testing {
    public void justTesting() throws IOException {
        ToBeMapped temp = new ObjectMapper().readValue(new File("path/to/test.json"), ToBeMapped.class);
    }
}
 
This will give me the following error:
 
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "value1" ...
 
If I add the @JsonProperty before each class variable as below, I can map the JSON file to the POJO without any errors. 
 
public class ToBeMapped {

     @JsonProperty
     String value1;

     @JsonProperty
     int value 2;
}
 
Is it true that I have to add this header to each class variable in order for Jackson's mapper to map the JSON file/stream to the object? Or I'm missing something in my code?
 
Thanks.

原文：https://stackoverflow.com/questions/49076059