Which of the following methods override the toString() method in the Object class
The Object class is the superclass of all other classes in Java and a part of the built-in java.lang package. If a parent class isn’t specified using the extends keyword, the class will inherit from the String toString() boolean equals(Object other) One commonly overriden Object method is toString(), which is often used to print out the attributes of an object. It is a
good idea to write your own toString() method in every class. In a subclass, toString() can call the superclass toString() method using super.toString() and then add on its own attributes. In the following code, the Person class overrides the Object toString() method and the Student class overrides the Person toString() method. They each add on their attributes. After trying the code below, add another subclass called APStudent that extends Student with a new attribute called APscore and override the toString() method to call the superclass method and then add on the APscore. Create an APStudent object in the main method to test it. 10.7.2. equals Method¶One of the important things that gets inherited from the Object superclass is the As seen in the code below, the Try to guess what this code will print out before running it. The Figure 1: A picture from the Java Visualizer showing that only p3 and p4 refer to the same object.¶ 10.7.3. Overriding the equals Method¶If you want to change how the inherited Try to guess what this code will print out before running it. Any class can override the inherited Try to guess what this code will print out before running it. Figure 2: A picture from the Java Visualizer showing the object references and objects.¶ You can step through this code in the Java Visualizer by clicking on the following link: OverrideEquals Ex. To write your own equals method, you must:
public boolean equals(Object other) { // Type cast other to your Classname Classname otherObj = (Classname) other; // Check if attributes are equal return (this.attribute == otherObj.attribute); // or this.attribute.equals(otherObj.attribute) if attribute a String } If you need to check multiple attributes, for example a name and an address for Person objects, you can use && to combine tests. return (this.attribute1 == otherObj.attribute1) && this.attribute2.equals(otherObj.attribute2) If you are writing an equals method for a subclass, you can call the superclass equals using the super keyword to check the attributes in the superclass and then check the attributes in the subclass. return super.equals(otherObj) && (this.attribute == otherObj.attribute) 10.7.4. Programming Challenge : Savings Account¶In the following code, a bank account class contains the account holder’s name and the money balance in the account. Work in pairs to write the following code and test each part before moving on to the next step:
Complete the subclass SavingsAccount below which inherits from Account and adds an interest rate variable. Write a toSTring and an equals method for it. 10.7.5. Summary¶
You have attempted of activities on this page In which of the following classes toString () method is already overridden?The Object class has some basic methods like clone(), toString(), equals(),.. etc. The default toString() method in Object prints “class name @ hash code”. We can override the toString() method in our class to print proper output.
Why should you override the toString () method?When you create a custom class or struct, you should override the ToString method in order to provide information about your type to client code. For information about how to use format strings and other types of custom formatting with the ToString method, see Formatting Types.
What does it mean to override the toString method?By overriding the toString( ) method, we are customizing the string representation of the object rather than just printing the default implementation. We can get our desired output depending on the implementation, and the object values can be returned.
Which of the following is toString () method defined?The toString() method of java.lang.Package class is used to get the String representation of this package instance. The method returns the String representation as a String value. Syntax: public String toString()
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