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What is the definition of 'Object class'?
The superclass of all other classes in Java, including arrays and other data types.
What is the definition of 'hashCode() method'?
A method that returns an integer representing the memory location of an object.
What is the definition of 'equals() method'?
A method that determines whether two objects are equal based on their properties.
What is the definition of 'toString() method'?
A method that returns a string representation of an object.
What is a 'hash code'?
An integer that represents the memory location of an object, based on its properties.
What does 'implicitly called' mean in the context of the Object constructor?
It means the Object constructor is automatically called when a class doesn't explicitly extend another class.
What is meant by 'overriding a method'?
Replacing a superclass's method implementation with a subclass's specific implementation.
What is the significance of the Object class in Java?
It provides default methods and properties common to all objects, forming the base of the class hierarchy.
Why is it important to override the equals() method?
To provide a meaningful comparison of objects based on their properties, rather than just memory addresses.
Why is it important to override the toString() method?
To provide a useful string representation of an object's state, making debugging and logging easier.
What is the relationship between equals() and hashCode()?
If two objects are equal according to equals(), they must have the same hash code.
What is the default behavior of toString() if not overridden?
It returns a string containing the object's class name, '@', and the object's hash code in hexadecimal format.
What package is the Object class part of?
The java.lang package.
When is the Object constructor implicitly called?
When a constructor is called in a class that doesn't explicitly extend another class.
What is the purpose of overriding the `hashCode()` method?
To ensure that objects considered equal by the `equals()` method have the same hash code, maintaining consistency in hash-based collections.
What is the default behavior of the `equals()` method if not overridden?
It compares object references, returning `true` only if the two references point to the same object in memory.
What is the output of `System.out.println(new Object());`?
A string representation of the Object, typically `java.lang.Object@<hashcode>`.