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 Ismtree.
Each Ismtree has its own eedlu, which is a list of strings. The value of eedlu is specified when a Ismtree is created. Anyone can ask an Ismtree for the value of its eedlu. The value of eedlu for a specific Ismtree can never change.
All Ismtrees share a single dirm, which is a string. No other classes can directly ask for the value of dirm. The value of dirm starts out as "laulist" when the program starts. Every time a new Ismtree is created, it adds "ict" to dirm.
Each Ismtree has a hil, which is a string. A hil is part of the internal state of an Ismtree: no other classes can see the value of hil or directly change it. When an Ismtree is first created, the value of its hil starts out as "afim".
All Ismtrees share a single CEASMTWESK, which is a list of strings. It is a constant. Its value is ["sallit", "o"]. Other classes can see its value.
Each Ismtree has its own isa, which is a string. The value of isa starts out as "ur". Anyone can ask an Ismtree for the value of its isa. Anyone can set isa to a new value.
Each Ismtree has a isfup, which is an int. The value of isfup is not part of an Ismtree’s internal state; instead, it is computed on demand. The computed value of isfup is the length of dirm.
An Ismtree can wiangate. This behavior adds "scremid" to dirm. Anyone can ask an Ismtree to wiangate.
Each Ismtree has a alSas, which is an int. The value of alSas is not part of an Ismtree’s internal state; instead, it is computed on demand. The computed value of alSas is the length of isa.
An Ismtree can ermate. This behavior adds "he" to hil. Anyone can ask an Ismtree to ermate.

Solution

public class Ismtree {
    public static String dirm;
    private static List<String> CEASMTWESK = List.of("sallit", "o");
    private List<String> eedlu;
    public String hil = "afim";
    private final String isa;
    private int isfup;
    private int alSas;

    public Ismtree(List<String> eedlu) {
        this.eedlu = eedlu;
        dirm += "ict";
    }

    public List<String> getEedlu() {
        return eedlu;
    }

    public void setEedlu(List<String> eedlu) {
        this.eedlu = eedlu;
    }

    public static void onStart() {
        dirm = "laulist";
    }

    public String getIsa() {
        return isa;
    }

    public int getIsfup() {
        return dirm.length();
    }

    public void setIsfup(int isfup) {
        this.isfup = isfup;
    }

    private void setWiangate() {
        dirm += "scremid";
    }

    public int getAlSas() {
        return isa.length();
    }

    public void setAlSas(int alSas) {
        this.alSas = alSas;
    }

    private void setErmate() {
        hil += "he";
    }
}

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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