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class Publisher {
  public static Publisher pub;
  int num;

  Publisher(int number) {
    // Initialization 
    this.num = number;
    // ...
    pub = this;
  }
}

Because, the field is nonvolatile and nonfinal, the statements within the constructor can be reordered by the compiler in such a way that the this reference is published before the initialization statements have executed.

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Compliant Solution (volatile and publish after initialization)

This noncompliant code example compliant solution declares the pub field as volatile and reduces the accessibility of the static class field to package-private so that untrusted callers beyond the current package cannot obtain the this reference.

class Publisher {
  static volatile Publisher pub;
  int num;

  Publisher(int number) {
    // Initialization 
    this.num = number;
    // ...
    pub = this;
  }
}

The constructor publishes the this reference after initialization has concluded. However, it is unsuitable because a legit caller can the caller must ensure that it does not see the default value of the field, before it is initialized (a violation of CON26-J. Do not publish partially-constructed objects).

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