com.fasterxml.jackson.databind.JsonMappingException：无法反序列化VALUE_NUMBER_INT令牌中的java.util.ArrayList实例

Question

I am trying to load a String value into List of Integers , here is the sample code

import java.util.List;

public class Test2 {
private List<Integer> list;

public List<Integer> getList() {
    return list;
}

public void setList(List<Integer> list) {
    this.list = list;
  }
}

import java.io.IOException;
import java.util.List;

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public class Test {

public static void main(String[] args) throws JsonParseException, JsonMappingException, IOException {
    ObjectMapper objectMapper = new ObjectMapper();
    String s = "1 2 3";
    //colorFrameAlertConfig.setColorNumber(objectMapper.readValue(configEntry.getValue(), List.class));
    Test2 t = new Test2();
    t.setList(objectMapper.readValue(s, List.class)); //getting exception here
    for(int i : t.getList()){
        System.out.println(i);
        }
  }

}

When I run the above code, I am getting following exception

Exception in thread "main" com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of VALUE_NUMBER_INT token
at [Source: 1 2 3; line: 1, column: 1]
at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:270)
at com.fasterxml.jackson.databind.DeserializationContext.reportMappingException(DeserializationContext.java:1234)
at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken(DeserializationContext.java:1122)
at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken(DeserializationContext.java:1075)
at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.handleNonArray(CollectionDeserializer.java:338)
at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:269)
at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:259)
at com.fasterxml.jackson.databind.deser.std.CollectionDeserializer.deserialize(CollectionDeserializer.java:26)
at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:3798)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2842)
at com.sample.Test.main(Test.java:17)

Answer 1

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