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Discussion 4: Inheritance Disclaimer There will be a lot of “Java rules” for the next week or so; bear with us! Agenda Problem 1 Mini lecture and Problem 2 Mini lecture and Problem 3 Problem 4 at your own pace Administrivia Project 1B and 1Gold released, due Saturday 2/16 Lab this week is peer-code review; attendance is required! Midterm 2/20, 8-10 PM, see midterm post for more details Room assignments out later on Guerrilla section this Sunday 2/17 from 2-4pm in 271, 273, 275 Soda One-on-one tutoring sign ups on Piazza weekly Resources: tinyurl.com/cz-disc4-sp19 Resources: tinyurl.com/cs61b-christine-zhou JUnit Testing What are the advantages and disadvantages of writing JUnit tests? Advantages: 1. Organized code - each test corresponds to different part of program 2. Can debug code locally 3. Documentation that your program works 4. Can reduce the amount of test code you need to write because you can reuse code Disadvantages: 1. Hard to use for higher-level testing (integration testing) Review: Inheritance public class Fish { String name; public Fish(String name) {...} public class Goldfish { String name; public Goldfish(String name) {...} Public void eat() {...} public void blink() {...} public void eat() { print(“bloop”); ... } } public void blink() {...} } Inheritance: extends extends (can extend only one class) Inherits all fields, methods, and nested classes Constructor is not inherited, but there will be an implicit call to super( ) in the beginning of the subclass’s constructor (need to make the Superclass before making the Subclass) If the Superclass’s constructor requires arguments, you must write an explicit call to super! Fish() { Goldfish() { this.name = “Bob”; super(); this.age = 12; this.name = “Bobfish”; } } Fish(String name) { Goldfish(String name) { this.name = name; super(name); this.age = 12; this.name

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