java - 如何Spring @requestparam验证字符串在字符串列表中

Question

我正在尝试用 @Valid 注释替换下面 Controller 中的硬编码验证

@GetMapping(value = "/fruits")
public List<String> fruits(
@RequestParam(value = "fruitType", defaultValue = "") String fruitType) {

    final ImmutableList<String> fruitTypes = 
            ImmutableList.of("Citrus", "Seed Less", "Tropical");

    if (!fruitTypes.contains(fruitType)) {
        throw new RuntimeException("Invalid Fruit type");
    }

    final ImmutableList<String> fruits = 
            ImmutableList.of("Apple", "Banana", "Orange");

    //filter fruits based on type, then return
    return fruits;
}

我知道我可以使用@Pattern 使用正则表达式来检查它，

    @GetMapping(value = "/fruits")
    public List<String> fruits(@RequestParam(value = "fruitType", defaultValue = "")
                                    @Valid  @javax.validation.constraints.Pattern(regexp="Citrus|Seed Less|Tropical")
                                      String fruitType) {
//      final ImmutableList<String> fruitTypes = ImmutableList.of("Citrus", "Seed Less", "Tropical");
//      if (!fruitTypes.contains(fruitType)) {
//          throw new RuntimeException("Invalid Fruit type");
//      }
        final ImmutableList<String> fruits = ImmutableList.of("Apple", "Banana", "Orange");
        //filter fruits based on type, then return
        return fruits;
    }

但是如果fruitType的列表不是静态的还有其他 Spring 方法吗？

Answer 1

当您根据自定义列表进行验证时，没有开箱即用的方法来执行此操作。但是，要验证类型，您可以将 FruitType 定义为 enum 并使用 @RequestParam 对其进行注释，例如:

enum FruitType{
    Apple,
    Banana,
    Orange;
}

public List<String> fruits(
@RequestParam(value = "fruitType") FruitTypefruitType) {
//Implementation