Explore
For Enterprise
Join for Free
Log In

Browse
Search
For Enterprise
Log In
Join for Free

Conditionals

Loading...

Java Programming: Solving Problems with Software

Duke University

4.6 (2,943 ratings) | 120K Students Enrolled

Course 1 of 4 in the Object Oriented Programming in Java Specialization

Learn to code in Java and improve your programming and problem-solving skills. You will learn to design algorithms as well as develop and debug programs. Using custom open-source classes, you will write programs that access and transform images, websites, and other types of data. At the end of the course you will build a program that determines the popularity of different baby names in the US over time by analyzing comma separated value (CSV) files. After completing this course you will be able to: 1. Edit, compile, and run a Java program; 2. Use conditionals and loops in a Java program; 3. Use Java API documentation in writing programs. 4. Debug a Java program using the scientific method; 5. Write a Java method to solve a specific problem; 6. Develop a set of test cases as part of developing a program; 7. Create a class with multiple methods that work together to solve a problem; and 8. Use divide-and-conquer design techniques for a program that uses multiple methods.

Skills You'll Learn

Algorithms, Problem Solving, String (Computer Science), Java Programming

Reviews

4.6 (2,943 ratings)

5 stars
2,151 ratings
4 stars
576 ratings
3 stars
119 ratings
2 stars
34 ratings
1 star
63 ratings

DN

Aug 08, 2016

You need a little more experience in coding that just the first course, or try not to leave everything by the end of the week(as I did) to find what you need for the assignments. Great course !

JS

May 19, 2019

Really practical course content with great tutorials. The programming assignments are fun and challenging and deal with real world data and problems which makes the course all the more useful!

From the lesson

Fundamental Java Syntax and Semantics

In this module, you will learn to write and run your first Java programs, including one program that prints “Hello!” in various countries’ languages and another where you will analyze the perimeters and other information of shapes. To accomplish these tasks, you will learn the basics of Java syntax and how to design stepwise solutions with programs. By the end of this module, you will be able to: (1) Download and run BlueJ, the Java programming environment for this course; (2) Access the documentation for the Java libraries specially designed for this course; (3) Edit, compile, and run a Java program; (4) Construct methods, variables, if else statements, and for each loops in Java; and (5) Use Iterables (like DirectoryResource) to run a program that iterates over multiples lines in a document or webpage or multiple files in a directory.

Conditionals3:25

Taught By

Owen Astrachan
Professor of the Practice
Robert Duvall
Lecturer
Andrew D. Hilton
Associate Professor of the Practice
Susan H. Rodger
Professor of the Practice

Transcript

Now, let's see how to execute code with conditional statements in it. Here we have a function f, which has some if and if, else statements. We have another function g. We'll assume we've used BlueJ's interface to invoke the method or function g to start with. The first statement declares a variable a. So we'll make a box for a. Even though this statement initializes a, it's going to take us several steps to compute that value. So we're going to leave a's value as 0, until we compute the value of the method f, applied to arguments 3 and 4. To evaluate this called to f, we make a frame, passing the values of the parameters. Note where to return and then we move the execution arrow to the first line f. The next line of code is an if statement, whose conditional expression is x less than y. We evaluate that expression and find 3 less than 4 is true. So I move the execution arrow into the then clause of this if statement and continue executing. The next statement is a call to System.out.println which is how you print something in Java. We write x less than y in our output and then, we return y plus x. This values follows the same rules you've already learned for return statements. We evaluate the expression to get the return value which is 7. Which is then what the function call evaluates to and will return back to the caller, destroying the frame for f. Now we're ready to finish initializing a, since we know that the call to the method f evaluated to 7. So, a is now 7. Now, we're ready for the next line of code in g. We make a box for b. And we call f passing in the arguments 7 and 5. Once again, we want to evaluate the condition x less than y. However, now x is 7 and y is 5. So x less than y is false. We find the closed curly brace for this if statement and see that the if statement has an else clause. So we move the execution arrow into the start of the else clause and continue executing from there. First, we see the System.out.println statement and this prints the line x is greater than or equal to y. Then we reach another if statement. This if statement is nested inside of the else but that doesn't affect the rules of how we evaluate it. We see that the conditional expression is false since 7 is not greater than or equal to 8. There's no else clause, so we move the execution arrow immediately past the closed curly brace and continue execution. There are not anymore statements inside the else clause. So remove the execution arrow outside of the else clause and keep going. Next, we have a return statement. So we evaluate the expression x minus 2 to find that the return value is 5. This then gets returned to the place we noted. So we destroy the frame for f and return back to g. We finished the assignment statement and now we're ready for the return statement from g. We execute that and we're done with method g.

Explore our Catalog

Join for free and get personalized recommendations, updates and offers.

Coursera provides universal access to the world’s best education, partnering with top universities and organizations to offer courses online.

© 2019 Coursera Inc. All rights reserved.

Get it on Google Play

Coursera
About
Leadership
Careers
Catalog
Certificates
MasterTrack™ Certificates
Degrees
For Enterprise
For Government
For Campus

Community
Learners
Partners
Developers
Beta Testers
Translators

Connect
Blog
Facebook
LinkedIn
Twitter
Instagram
YouTube
Tech Blog

More
Terms
Privacy
Help
Accessibility
Press
Contact
Directory
Affiliates