Public field from String - How can you get a public field vis its name(string)

Question

So in a class (ImportantClass123) I have this:

public AnotherImportantClass aReallyImportantClass;

How do I return

AnotherImportantClass

via knowledge of what its named as a field:

aReallyImportantClass

Something like

ImportantClass123.getFieldWithName("aReallyImportantClass");

?

How would I write getFieldWithName? and what would be its return type? Class?

you'll need something like reflection api, [read this](http://stackoverflow.com/questions/160970/how-do-i-invoke-a-java-method-when-given-the-method-name-as-a-string) — Bagus Tesa, Dec 23 '16 at 04:00
https://docs.oracle.com/javase/tutorial/reflect/member/fieldValues.html — shmosel, Dec 23 '16 at 04:01
@shmosel OP is looking for the type of the field, not the value. Surprisingly I can't find a duplicate for that. — Erwin Bolwidt, Dec 23 '16 at 04:23
https://docs.oracle.com/javase/tutorial/reflect/member/fieldTypes.html — shmosel, Dec 23 '16 at 04:27

score 1 · Answer 1 · answered Dec 23 '16 at 04:23

You can use reflection to get to that information. The method Class.getField(String) returns a Field object for the public field given by name. And the Field object has a method getType() that will give you the type of that field:

public class Snippet {
    public Integer x;

    public static void main(String[] args) throws Exception {
        Field x = Snippet.class.getField("x");
        Class<?> type = x.getType();
        System.out.println("Type of field x: " + type);
    }
}

Public field from String - How can you get a public field vis its name(string)

1 Answers1