Class declarations and object modeling: Correct Solution

Translate the specification below into an idiomatic Java class definition.

(In this context, "idiomatic" means following the common style and conventions of the language.)

One kind of thing that exists in our model is a Purstpla.
Each Purstpla has its own toRo, which is a string. The value of toRo is specified when a Purstpla is created. Anyone can ask a Purstpla for the value of its toRo. The value of toRo for a specific Purstpla can never change.

Solution

public class Purstpla {
    private String toRo;

    public Purstpla(String toRo) {
        this.toRo = toRo;
    }

    public String getToRo() {
        return toRo;
    }

    public void setToRo(String toRo) {
        this.toRo = toRo;
    }
}

Things to check in your solution:

Is every public and private modifier correct?
Are the correct items static?
Are the correct items final?
Are all the variable types and method return types correct?
Are the class members in the correct order? It should be: (1) static variables, (2) instance variables, (3) constructors, (4) methods.
Do members have the correct capitalization?

Acceptable variations in the solution:

It is OK if you initialized non-static variables in the constructor instead of in the declaration. (Ask your instructor if you aren’t clear what this means.) Note that static variables must be initialized in the declaration.
It is OK if you used a slightly different but equivalent form of an expression, such as += 1 instead of ++.

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