Validation

Spring Shell 与 Bean Validation API 相集成，支持命令参数的自动和自文档式的限制。

Spring Shell integrates with the Bean Validation API to support automatic and self-documenting constraints on command parameters.

将遵守命令参数上的注释和方法级别的注释，并在执行命令前触发验证。考虑以下命令：

Annotations found on command parameters and annotations at the method level are honored and trigger validation prior to the command executing. Consider the following command:

	@ShellMethod("Change password.")
	public String changePassword(@Size(min = 8, max = 40) String password) {
		return "Password successfully set to " + password;
	}

从前面的示例中，您将免费获得以下行为：

From the preceding example, you get the following behavior for free:

shell:>change-password hello
The following constraints were not met:
	--password string : size must be between 8 and 40 (You passed 'hello')