![]() ![]() ![]() You can verify that the constructor of A sees an uninitialized B by (only for academic purpose, please) downcasting the this pointer in A's constructor and inspecting B.x. ![]() The second thing is that even if A's constructor in your example were to assign to B.x, it would happen before the B-part of the object is constructed (as objects are constructed starting with Object's constructor and then walking down the class hierarchy ) and the constructor of B would overwrite it. Casting a variable up to its superclass (as happens implicitly to the this pointer) will not affect how methods are resolved but does change how attributes are. This means that attributes shadow while methods overwrite. The tool javap from the JDK can disassemble Java classes. We can access both non-parameterized and parameterized constructor of superclass. What is the super() constructor of Object (the root of the class hierarchy). The superclass constructor can be invoke in sub class by using the super () constructor. super () Constructor The super () is mainly used for invoking base class member functions and constructors. If a class doesnt have a constructor, the Java compiler automatically creates a default constructor during run-time. The child class can inherit all properties (methods, variables) and behavior of parent expect parent class constructor.&. As many others have meanwhile pointed out, attributes are resolved statically in Java, while methods are. Because a superclass constructor is always invoked as the first statement of its subclass constructor, the body of the Object constructor always runs first. As many others have meanwhile pointed out, attributes are resolved statically in Java, while methods are resolved dynamically. A Java constructor must not have a return type. Solved-Super constructor in a subclass - Java-Java. ![]()
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