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MappingInstantiationException: Failed to instantiate java.util.List using constructor NO_CONSTRUCTOR with arguments 

Reason

Entity classes mapped by a set in Mongo Library

@Data
@NoArgsConstructor
@AllArgsConstructor
@Document(collection = "a")
public class A {
	
	private List<B> b; // this is list
	
	@Data
    @Builder
    @NoArgsConstructor
    @AllArgsConstructor
    public static class B {

        private String bb;
    }
}

A data format of set

{ 
    "_id" : ObjectId("62df884326d4311d9c80de8d"), 
    "b" : {
        "bb" : "test" //this is object
    }
}

Solution:

Modify entity classes or process problem data.