V6052. Calling an overridden method in parent-class constructor may lead to use of uninitialized data.

The analyzer has detected a parent-class constructor that uses a method overridden in the derived class. As a result, the overridden method can be used by uninitialized class fields.

This behavior occurs when you fail to follow the class initialization procedure stated in JLS [12.5].

Consider the following example:

public class Parent {
  private String parentStr = "Black";

  public Parent () {

  public void printInfo () {
    System.out.println("parentStr: " + parentStr);

public class Child extends Parent {
  private int childInt;
  private String childStr;

  public Child() {
    this.childInt = 25;
    this.childStr = "White";

  public void printInfo () {
    System.out.println("childInt: "+childInt+";childStr: "+childStr);

If we execute the following line:

Child obj = new Child();

the program will print:

parentStr: Black
childInt: 0 ; childStr: null

As seen from this fragment, the overridden method 'printInfo' was called in the parent-class constructor of the 'Parent' class, while the derived 'Child' class was not fully initialized – hence the default values, rather than user-specified values, of the 'childInt' and 'childStr' fields.

The conclusion is this: make sure your parent-class constructors do not use methods that could be overridden in child classes. And if you do use a class method in a constructor, declare it final or private.

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