Field Less Accessible

The visibility of a library field is decreased by modifying its access modifier.

Example

The access modifier of the field name in the library class Person is changed from public to protected.

public class Person {
-  public String name;
+  protected String name;
}

Broken Uses

Hereafter, we list the broken uses that are currently detected by Maracas.

• 1. Field accesses of a now-private field
• 2. Field accesses of a now-package-private field from a different package
• 3. Field accesses of a now-protected field from a different package or a non-child class

1. Field accesses of a now-private field

Example

The access modifier of the field name in the library class Person is changed from public to private.

public class Person {
-  public String name;
+  private String name;
}

The method displayPerson—defined in the PeopleInfo class in a client project—accesses the now-private name field. Then, a broken use is reported pointing to the field access expression.

public class PeopleInfo {
  public void displayPerson(Person person) {
    // Broken use reported here
    String personName = person.name;
    System.out.println(personName);
  }

}

2. Field accesses of a now-package-private field from a different package

Example

The access modifier of the field name in the library class Person is changed from public to package-private (by removing the modifier).

public class Person {
-  public String name;
+  String name;
}

The method displayPerson—defined in the PeopleInfo class in a client project—accesses the now-package-private name field. Then, a broken use is reported pointing to the field access expression.

public class PeopleInfo {
  public void displayPerson(Person person) {
    // Broken use reported here
    String personName = person.name;
    System.out.println(personName);
  }

}

3. Field accesses of a now-protected field from a different package or a non-child class

Example

The access modifier of the field name in the library class Person is changed from public to protected.

public class Person {
-  public String name;
+  protected String name;
}

The method displayPerson—defined in the PeopleInfo class in a client project—accesses the now-protected name field. Then, a broken use is reported pointing to the field access expression.

public class PeopleInfo {
  public void displayPerson(Person person) {
    // Broken use reported here
    String personName = person.name;
    System.out.println(personName);
  }

}