Properties in '@ConfigurationProperties' annotated type shouldn't be able to define the same '@Name'

[snicoll]

Courtesy of @YannCebron

@ConfigurationProperties("vet")
public class VetConfigProps {

    @Name("aaa")
    private String company;

    @Name("aaa")
    private String name;

    public void setCompany(String company) {
        this.company = company;
    }

    public String getCompany() {
        return company;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

}

The annotation processor completes successfully and generates the following JSON:

{
  "groups": [
    {
      "name": "vet",
      "type": "org.springframework.samples.petclinic.vet.VetConfigProps",
      "sourceType": "org.springframework.samples.petclinic.vet.VetConfigProps"
    }
  ],
  "properties": [
    {
      "name": "vet.aaa",
      "type": "java.lang.String",
      "sourceType": "org.springframework.samples.petclinic.vet.VetConfigProps"
    }
  ],
  "hints": [],
  "ignored": {
    "properties": []
  }
}

At runtime setting vet.aaa binds to the two annotated fields. I believe this should raise an error as two properties have the same ID (which they can't).

[snicoll]

@mango766 we've decided to throw an exception with such pattern. Would you like to submit a PR to that effect?

[Pratapchandradeo]

Hi @snicoll , I’d like to take this up. I can work on adding validation to detect duplicate @name annotations in @ConfigurationProperties and ensure an exception is thrown as discussed.

Please assign this issue to me if it’s available.

[Ak3161]

Duplicate @Name values in a @ConfigurationProperties class are not detected. If two fields use the same @Name, they both bind to the same property without any warning:

@ConfigurationProperties("vet")
public class VetConfigProps {

@Name("aaa")
private String company;

@Name("aaa")
private String name;

}

properties
vet.aaa=test

Both fields receive the same value, and metadata only shows a single property (vet.aaa).

This can be confusing—should duplicate @Name mappings be validated or at least produce a warning?

Solution could be u can use unique property names or better to use custom validator