How to allow variables being set only once in java

You should generally use the builder pattern for cases like this: https://en.wikipedia.org/wiki/Builder_pattern

MyClass instance = (new MyClassBuilder())
    .setField1(...)
    .setField2(...)
    .build();

Your builder object lets you set all the fields and options you like, but the MyClass instance that it builds does not.

Answer:1

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