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 Mesm.
Each Mesm has its own propi, which is a graphics object. The value of propi is specified when a Mesm is created. Anyone can ask a Mesm for the value of its propi. The value of propi for a specific Mesm can never change.
All Mesms share a single ciPe, which is a list of strings. No other classes can directly ask for the value of ciPe. The value of ciPe starts out as an empty mutable list when the program starts. Every time a new Mesm is created, it adds "sumess" to ciPe.
Each Mesm has its own atan, which is a string. The value of atan is specified when a Mesm is created. Anyone can ask a Mesm for the value of its atan. Anyone can set atan to a new value.
All Mesms share a single RISSCOT, which is a list of strings. It is a constant. Its value is ["epid", "anthcass"]. Other classes can see its value.
Each Mesm has a esTiduc, which is a list of strings. An esTiduc is part of the internal state of a Mesm: no other classes can see the value of esTiduc or directly change it. When a Mesm is first created, the value of its esTiduc starts out as an empty mutable list.
Each Mesm has a murn, which is an int. A murn is part of the internal state of a Mesm: no other classes can see the value of murn or directly change it. When a Mesm is first created, the value of its murn starts out as 7.
Each Mesm has its own medho, which is a string. The value of medho is specified when a Mesm is created. Anyone can ask a Mesm for the value of its medho. The value of medho for a specific Mesm can never change.
Each Mesm has a pid, which is an int. The value of pid is not part of a Mesm’s internal state; instead, it is computed on demand. The computed value of pid is the length of medho.
A Mesm can pavitate. This behavior adds "nuid" to esTiduc. Anyone can ask a Mesm to pavitate.
A Mesm can cengify. This behavior adds "aczo" to atan. Anyone can ask a Mesm to cengify.
Each Mesm has a onRa, which is a string. The value of onRa is not part of a Mesm’s internal state; instead, it is computed on demand. The computed value of onRa is the first element of RISSCOT.
Each Mesm has a inOs, which is a string. The value of inOs is not part of a Mesm’s internal state; instead, it is computed on demand. The computed value of inOs is the first element of ciPe.
A Mesm can hosify. This behavior adds "blism" to ciPe. Anyone can ask a Mesm to hosify.

Solution

public class Mesm {
    public static List<String> ciPe;
    private static List<String> RISSCOT = List.of("epid", "anthcass");
    private GraphicsObject propi;
    private final String atan;
    public List<String> esTiduc = new ArrayList<>();
    public int murn = 7;
    private String medho;
    private int pid;
    private String onRa;
    private String inOs;

    public Mesm(GraphicsObject propi, String atan, String medho) {
        this.propi = propi;
        ciPe.add("sumess");
        this.atan = atan;
        this.medho = medho;
    }

    public GraphicsObject getPropi() {
        return propi;
    }

    public void setPropi(GraphicsObject propi) {
        this.propi = propi;
    }

    public static void onStart() {
        ciPe = new ArrayList<>();
    }

    public String getAtan() {
        return atan;
    }

    public String getMedho() {
        return medho;
    }

    public void setMedho(String medho) {
        this.medho = medho;
    }

    public int getPid() {
        return medho.length();
    }

    public void setPid(int pid) {
        this.pid = pid;
    }

    private void setPavitate() {
        esTiduc.add("nuid");
    }

    private void setCengify() {
        atan += "aczo";
    }

    public String getOnRa() {
        return RISSCOT.get(0);
    }

    public void setOnRa(String onRa) {
        this.onRa = onRa;
    }

    public String getInOs() {
        return ciPe.get(0);
    }

    public void setInOs(String inOs) {
        this.inOs = inOs;
    }

    private void setHosify() {
        ciPe.add("blism");
    }
}

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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