Unit 1 - Java Robotics Lab Vocabulary

Vocabulary flashcards covering Java basics, object-oriented concepts, constructors, inheritance, maps, and lab-specific conventions.

Comment line

A line starting with // that the compiler ignores; used to annotate code.

import

Statement to bring in classes from other packages so you can use them in your program.

class

A blueprint/container for code that defines fields and methods for objects.

main method

The entry point of a Java program: public static void main(String[] args); statements run in order.

Display.openWorld

A class method that loads a map into the graphics window.

Display.setSize

Sets the size of the display window (width by height).

Display.setSpeed

Controls the execution speed of robot actions in the display.

Robot

A class representing a robot; used to create robot objects with new Robot().

instantiation

Creating an object from a class using the new keyword.

object reference

A name that points to an instantiated object (e.g., karel is a reference to a Robot instance).

dot notation

Calling a method on an object using objectName.method().

constructor

A special method that initializes a new object; has the same name as the class and no return type.

super

A call inside a subclass constructor to invoke the superclass constructor and initialize inherited fields.

inheritance

A relationship where a subclass gains fields and methods from a superclass (extends).

isa relationship

Label used in UML to indicate an inheritance (is-a) relationship.

has-a relationship

Label used in UML to indicate composition (has-a); one object contains another.

driver class

A class that contains the main method and drives the program by creating objects and issuing commands.

resource class

A class whose methods must be invoked on instantiated objects; not runnable by itself.

static

Modifier for class methods (not tied to an instance), e.g., main() or Display.setSize().

bytecode

The compiled .class form of Java source that runs on the Java Virtual Machine.

javac

The Java compiler that translates .java files into .class bytecode.

java

The runtime launcher that runs a class by invoking its main method.

identifier

A name for a class, method, or variable; cannot start with a number and is case-sensitive; cannot be a Java keyword.

naming conventions

Class names start with uppercase; methods/variables start with lowercase; constants are ALL CAPS.

Cartesian coordinate system

Maps use coordinates; the bottom-left corner is (1, 1).

Unit1/maps

Folder containing predefined map files used by the labs.

instantiate

To create an instance of a class using new.

definite iteration

Repeating a block a fixed number of times using a for-loop.

for-loop syntax

for (initialization; condition; update) { … } for definite iteration.

actual argument

The value passed to a method when it is called.

formal argument

The parameter in a method signature that receives the actual argument.

default constructor

A no-argument constructor that creates an object in its default state.

four-argument constructor

A constructor that takes four parameters and passes them up to the superclass with super.

no-suitable-constructor error

Compiler error when the arguments do not match any constructor in the class hierarchy.

one-argument constructor

A constructor that takes a single parameter to initialize a field.

class method

A method defined as static; belongs to the class, not to any object.

arena map

A specific 10x10 map used in Lab04 for demonstrations.