Question

In short, if you want to write a map of e.g. constants in Java, which in e.g. Python and Javascript you would write as a literal,

T<String,String> CONSTANTS =
{
    "CONSTANT_NAME_0": CONSTANT_VALUE_0 ,
    "CONSTANT_NAME_1": CONSTANT_VALUE_1 ,
    "CONSTANT_NAME_2": CONSTANT_VALUE_2 ,
    //...
} ;

is there a Class or any preset Object that you can use for writing a data structure like that?

Answer 1

Constants? I’d use an enum.

public enum Constants { 
    NAME_1("Value1"),
    NAME_2("Value2"),
    NAME_3("Value3");

    private String value;

    Constants(String value) {
        this.value = value;
    }

    public String value() {
        return value;
    }
}

Value for e.g. NAME_2 can be obtained as follows:

String name2value = Constants.NAME_2.value();

Only give the enum a bit more sensible name, e.g. Settings, Defaults, etc, whatever those name/value pairs actually represent.