Mongotemplate:如何将结果字段转换为自定义Java类型？

import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.aggregation.Aggregation;
import org.springframework.data.mongodb.core.aggregation.AggregationResults;
import org.springframework.data.mongodb.core.aggregation.ProjectionOperation;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;

// 创建自定义Java类型
public class CustomType {
    private String field1;
    private int field2;
    
    // 省略构造函数和getter/setter方法
}

// 在代码中使用Mongotemplate进行查询操作
public class MainClass {
    private MongoTemplate mongoTemplate;
    
    public CustomType getCustomType() {
        // 创建ProjectionOperation对象，指定要转换的字段和自定义Java类型
        ProjectionOperation projectionOperation = Aggregation.project("field1", "field2")
                .andExclude("_id")
                .and("field2").as("field2");
        
        // 创建Aggregation对象，指定查询条件和投影操作
        Aggregation aggregation = Aggregation.newAggregation(
                Aggregation.match(Criteria.where("field1").is("value")),
                projectionOperation
        );
        
        // 执行查询操作
        AggregationResults<CustomType> results = mongoTemplate.aggregate(aggregation, "collectionName", CustomType.class);
        
        // 获取查询结果
        CustomType customType = results.getUniqueMappedResult();
        
        return customType;
    }
}