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 an Esost.
Each Esost has its own zua, which is a string. The value of zua is specified when a Esost is created. Anyone can ask an Esost for the value of its zua. The value of zua for a specific Esost can never change.

Solution

public class Esost {
    private String zua;

    public Esost(String zua) {
        this.zua = zua;
    }

    public String getZua() {
        return zua;
    }

    public void setZua(String zua) {
        this.zua = zua;
    }
}

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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