resources.report.rules.pmd.ConstructorCallsOverridableMethod.html Maven / Gradle / Ivy
ConstructorCallsOverridableMethod
ConstructorCallsOverridableMethod
Calling overridable methods during construction poses a risk of invoking methods on an incompletely constructed object and can be difficult to debug. It may leave the sub-class unable to construct its superclass or forced to replicate the construction process completely within itself, losing the ability to call super(). If the default constructor contains a call to an overridable method, the subclass may be completely uninstantiable. Note that this includes method calls throughout the control flow graph - i.e., if a constructor Foo() calls a private method bar() that calls a public method buz(), this denotes a problem.
This rule is defined by the following Java class: net.sourceforge.pmd.lang.java.rule.design.ConstructorCallsOverridableMethodRule
Example(s):
public class SeniorClass {
public SeniorClass(){
toString(); //may throw NullPointerException if overridden
}
public String toString(){
return "IAmSeniorClass";
}
}
public class JuniorClass extends SeniorClass {
private String name;
public JuniorClass(){
super(); //Automatic call leads to NullPointerException
name = "JuniorClass";
}
public String toString(){
return name.toUpperCase();
}
}