Java Foundations and Program Design Free Online FlashCards

What is the productive programming cycle?

A reliable cycle is to understand the problem, plan an algorithm, implement it, test it, debug and improve it, and explain why it works.

Where does a Java application begin execution?

Execution begins in the `main` method: `public static void main(String[] args)` in a Java application.

How should a public Java class be named on disk?

Normally, a public class named `Greeting` must be saved in a file named `Greeting.java`.

What is the difference between declaration and assignment?

A declaration gives a variable its type and name; an assignment stores a value in it. For example, `int score;` declares, while `score = 95;` assigns.

Which Java types fit whole numbers, decimals, logic, characters, and text?

Use `int` for whole numbers, `double` for decimals, `boolean` for logical values, `char` for one character, and `String` for text.

What value does `8 + 4 * 2` produce?

`16`. Multiplication is evaluated before addition, so `4 * 2` is calculated before `8 + 8`.

How do integer division and remainder differ in Java?

With two `int` operands, `/` performs integer division and discards the fractional part; `%` returns the remainder. Thus, `7 / 2` is `3` and `7 % 2` is `1`.

What is `(int) 9.99`?

`9`. Casting `9.99` to `int` removes the fractional portion; it does not round the value.

What does `"Average: " + (5 + 10) / 2.0` produce?

`Average: 7.5`. Parentheses make Java add `5 + 10` before dividing by `2.0`, then concatenate the result with the label.

How do `print` and `println` differ?

`print` displays text without moving to a new line; `println` displays text and then moves to the next line.

Why can `nextInt()` followed by `nextLine()` be surprising?

`nextInt()` reads an integer token, while `nextLine()` reads the rest of the current line. After `nextInt()`, an extra `nextLine()` may be needed to consume the remaining line break.

What are the three stages of a basic Java program?

Read the data, process it with expressions and assignments, then display the result. This is the input–process–output pattern.