优化DynamoDB日期类型转换：解决ClassCastException

public class LocalDateConverter implements DynamoDBTypeConverter<Long, LocalDate> {
    @Override
    public Long convert(LocalDate date) {
        return date == null ? null : date.toEpochDay();
    }

    @Override
    public LocalDate unconvert(final Long days) {
        return days == null ? null : LocalDate.ofEpochDay(days);
    }
}

@DynamoDBRangeKey(attributeName = "dateTimestamp")
@DynamoDBTypeConverted(converter = LocalDateConverter.class)
public LocalDate getSortKey() {
    return priceCalendarIdentity != null ? priceCalendarIdentity.getSortKey() : null;
}

import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTypeConverter;
import java.time.LocalDate;
import java.time.format.DateTimeParseException;

/**
 * DynamoDBTypeConverter for converting LocalDate to and from String (ISO-8601 format).
 */
public class LocalDateConverter implements DynamoDBTypeConverter<String, LocalDate> {

    /**
     * Converts a LocalDate object to its String representation (YYYY-MM-DD) for storage in DynamoDB.
     *
     * @param date The LocalDate object to convert.
     * @return The String representation of the date, or null if the input is null.
     */
    @Override
    public String convert(LocalDate date) {
        return date == null ? null : date.toString(); // e.g., "2023-10-26"
    }

    /**
     * Converts a String representation of a date (YYYY-MM-DD) from DynamoDB back to a LocalDate object.
     * Includes basic error handling for parsing.
     *
     * @param dateString The String to convert.
     * @return The LocalDate object, or null if the input is null, empty, or cannot be parsed.
     */
    @Override
    public LocalDate unconvert(final String dateString) {
        if (dateString == null || dateString.isEmpty()) {
            return null;
        }
        try {
            return LocalDate.parse(dateString); // Parses "YYYY-MM-DD" string
        } catch (DateTimeParseException e) {
            // Log the error or throw a more specific custom exception if necessary
            System.err.println("Error parsing date string '" + dateString + "' to LocalDate: " + e.getMessage());
            return null; // Or re-throw a runtime exception wrapped for clarity
        }
    }
}

// 示例模型类片段
public class PriceCalendarIdentity {
    private LocalDate sortKey; // 假设这是LocalDate类型的字段

    public LocalDate getSortKey() {
        return sortKey;
    }

    public void setSortKey(LocalDate sortKey) {
        this.sortKey = sortKey;
    }
}

public class MyDynamoDBModel {

    private PriceCalendarIdentity priceCalendarIdentity; // 假设此字段包含sortKey

    @DynamoDBRangeKey(attributeName = "dateTimestamp")
    @DynamoDBTypeConverted(converter = LocalDateConverter.class)
    public LocalDate getSortKey() {
        // 确保这里返回的是LocalDate类型
        return priceCalendarIdentity != null ? priceCalendarIdentity.getSortKey() : null;
    }

    // Setter for getSortKey (if needed for object creation)
    public void setSortKey(LocalDate sortKey) {
        if (this.priceCalendarIdentity == null) {
            this.priceCalendarIdentity = new PriceCalendarIdentity();
        }
        this.priceCalendarIdentity.setSortKey(sortKey);
    }
}