将CSV文件解析到Castom对象，该文件具有诸如Enum之类的字段

发布于 2025-02-07 01:24:10 字数 1413 浏览 0 评论 0原文

问题是，我应该如何处理枚举字段以进行正确的解析。也许它有另一种注释或其他内容...我从CSV文件中获得符号，并且必须以正确的类型创建枚举。但是我该怎么做？...

这个实现传达了太长的消息。第一个字符串是：
线程“ main” java.lang.runtimeException中的例外：com.opencsv.exceptions.csvbeanintrospectionsception：确定给定豆类类型的基本实例（以及通过递归创建的下属豆（如果适用）确定为不可能是不可能的。

它将其扔进字符串中，并使用[.parse（）;]

公共类FileServiceImplementationsblincementsfileservice {

public List<FruitTransaction> read(File file) {
        try (FileReader reader = new FileReader(file)) {
            return new CsvToBeanBuilder(reader)
                    .withType(FruitTransaction.class)
                    .build()
                    .parse();
        } catch (IOException e) {
            throw new RuntimeException("Cannot read file: " + file.getName() + e);
        }
    }
}

public class FruitTransaction {
    @CsvBindByPosition(position = 0)
    private Operation operation;
    @CsvBindByPosition(position = 1)
    private String fruit;
    @CsvBindByPosition(position = 2)
    private int quantity;

...
// and my nested enum class:
public enum Operation {
        BALANCE("b"),
        SUPPLY("s"),
        PURCHASE("p"),
        RETURN("r");

        private String operation;

        Operation(String operation) {
            this.operation = operation;
        }
    }
}

my input data from CSV file:
b,banana,20
b,apple,100
s,banana,100
p,banana,13
r,apple,10
p,apple,20
p,banana,5
s,banana,50

原文

The question is, how I should handle ENUM fields for right parsing. Maybe it has another sort of annotation or something... I get symbol from csv file and have to create the enum in right type. But how can I do that?...

This implementation throw too long message. The first string is:
Exception in thread "main" java.lang.RuntimeException: com.opencsv.exceptions.CsvBeanIntrospectionException: Basic instantiation of the given bean type (and subordinate beans created through recursion, if applicable) was determined to be impossible.

It throws it in a string with [.parse();]

public class FileServiceImplementation implements FileService {

public List<FruitTransaction> read(File file) {
        try (FileReader reader = new FileReader(file)) {
            return new CsvToBeanBuilder(reader)
                    .withType(FruitTransaction.class)
                    .build()
                    .parse();
        } catch (IOException e) {
            throw new RuntimeException("Cannot read file: " + file.getName() + e);
        }
    }
}

public class FruitTransaction {
    @CsvBindByPosition(position = 0)
    private Operation operation;
    @CsvBindByPosition(position = 1)
    private String fruit;
    @CsvBindByPosition(position = 2)
    private int quantity;

...
// and my nested enum class:
public enum Operation {
        BALANCE("b"),
        SUPPLY("s"),
        PURCHASE("p"),
        RETURN("r");

        private String operation;

        Operation(String operation) {
            this.operation = operation;
        }
    }
}

my input data from CSV file:
b,banana,20
b,apple,100
s,banana,100
p,banana,13
r,apple,10
p,apple,20
p,banana,5
s,banana,50

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