Question

Is there some similar feature in Java as ‘attributes’ in Delphi ?

Example explanation of Attributes in Delphi:
http://www.malcolmgroves.com/blog/?p=476

Att.

Answer 1

From that article, you’re looking for Java Annotations. They let you do things like:

@SomeInfo(author = "Bob", year = 1993)
class Foo {
    @SomeInfo(author = "me", somethingElse = "abcdefg")
    private int x = 5;

    @SomeInfo(author = "Fred", column = "order")
    public int getX() {
        return x;
    }
}

where @SomeInfo is an annotation. They can be applied to classes, fields, and methods, and they carry metadata about the thing they annotate, which can be read at runtime if they have the appropriate retention. E.g:

@Retention(RetentionPolicy.RUNTIME)
@interface SomeInfo {
    String author();
    int year() default -1;
    String column() default "";
    String somethingElse() default "";
}

class Main {
    public static void main(String[] args) throws Exception {
        List<AnnotatedElement> annotatedElements =
            new ArrayList<AnnotatedElement>();
        annotatedElements.add(Foo.class);
        annotatedElements.add(Foo.class.getDeclaredField("x"));
        annotatedElements.add(Foo.class.getDeclaredMethod("getX"));
        for (AnnotatedElement annotatedElement : annotatedElements) {
            System.out.println("Author of {" + annotatedElement + "} = " +
                annotatedElement.getAnnotation(SomeInfo.class).author());
        }
    }
}