CMSC131 Midterm #1 Java Terminology

Java Compiler

Converts source code into machine code file, and runs everything at once 

Java Interpreter

Converts machine code when program is run, goes LINE by LINE to understand what each line does. Debuggers are based on interpreters 

Interpreter vs Compiler

Java Virtual Machine

loads up all bytecode from .class files and runs program

Scanner Syntax

import java.util.Scanner;

High level languages

java, python

low level languages

assembly, c

primitive data

data type that canot be manipulated (int, double, float, long, short, byte, boolean, char)

primitiveType name = data;

object data

String, Scanner (notice all uppercase)

ObjectType name = new ObjectType();

pass by values

a mechanism to pass everything in java

static methods

with static methods, objects are NOT created

syntax: className.methodName(); or className.variableName();

non-static

with non-static methods, objects ARE created

syntax: object.methodName();

a<<b

shifts to the left by b positions, filling with 0’s

a>>b

shifts to the right by b positions, filling with the sign bit.

bytecode

code executed by the JVM

syntax error

an error in the code that violates the grammatical rules of the programming language.

runtime error

an error that occurs during the execution of a program, leading to unexpected behavior.

Math random syntax

Math.random*((max-min) +1) + min;

Method overloading

when you have multiple methods of the same name but different parameters

Method overriding

Refers to inheritance, when same method has new implementation

Reference copy

Copy of object, both point to same object (same memory)

tail recursion

answer is returned at very last call

non tail recursion

answer is built up with each recursive call