CH 2- JAVA
String firstString = "Carrington Harrod";
Define a String variable, -firstString-, with the value "Your Full Name."
String name; name = JOptionPane.showInputDialog("Enter your name."); -------Carrington Harrod JOptionPane.showMessageDialog(null, "Hello, + name); System.exit(0); causes the program to end
Display a message dialog box using the input method using your name
import javax.swing.JOptionPane; JOptionPane.showMessageDialog(null, "Hello World); Message- Hello World
Display a message dialog box using the output method
single line comment multi-line comment documentation comment
// symbol /*, */ symbol /** */ (can be read and processed by a program named javadoc)
char myChar = firstName.charAt(3) S.o.p( +myChar); the answer will be i
//ex of a char data type String firstName = "carrington"; give the java statement that will determine the 4th character of the String firstName and store into myChar
main method
every java application program must have _____________
x += 5; is equivalent to x=x+5 y-= 2; is equivalent to y = y-2 z*= 10; is equivalent to z = z*10 a /= b; is equivalent to a = a/b c %= 3; is equivalent to c = c%3
examples of combined assigned operators
byte = x; Scanner keyboard = new Scanner (System.in); S.o.p( "Enter a byte value"); x = keyboard.nextByte( ); int number; Scanner keyboard = new Scanner (System.in); S.o.p.("Enter an integer value"); number = keyboard.nextInt( ); String name; Scanner keyboard = new Scanner (System.in); S.o.p( "Enter your name"); name = keyboard.nextLine();
examples of the scanner class methods
littleNum = (short)bigNum; x = (long) 3.7; number = (int) 72.567 value = (float) x; value = (byte) number;
examples of using the cast operator
float number; number = 23.5F;
how to make a float compatible with a double
= 16
how to raise a number to a power in java Math.pow(4.0,2.0);
byte 1, short 2, int 4, long 8, float 4, double 8,
identify the 6 data types and their byte sizes
class header
java source file and the ______ must be the same except for the file extension
final
key word to declare a named constant that cannot be changed in the program
semicolon
marks the end of a statement in Java
variable
named storage location in the computer's memory
.java
names of the Java source code files end with
- (unary negation) * / % + - (lowest precedence)
place the arithmetic operators in order
identifier
programmer-defined name that represents some element of a program
method header
public static void main(String[ ] args)
Today we sold 20 bushels of apples
read what this statement will- int apples; apples = 20; S.o.p.("Today we sold " + apples + " bushels of apples.");
13 2 28 4 6
solve the expressions and their values 5+2*4 10/2-3 8+12*2-4 4+17%2-1 6-3*2+7-1
string concatenation operator
the + sign is known as the when used with strings
char
the _______ type is used to store characters
class definition
the class header (ex. public class Simple(name given) marks the beginning of the ______ ________
string literal
the group of characters inside the quotation marks-SOP("Programming is great fun!"); - is called a
literal
value that is written into the code of a program
true or false
what two variables does the boolean method hold
Programming is great fun! I can't get enough of it!
what will this statement print public class TwoLines { public static void main (String[ ] args) { S.o.pln("Programming is great fun!"); S.o.pln("I can't get enough of it!"); } }
key words
words that have special meaning in java programming
Scanner keyboard = new Scanner (System.in);
write a java statement to create a scanner object (placed inside of the main method)
String firstString = firstString.toUpperCase(); S.o.p( + firstString); CARRINGTON HARROD
Str firstString = "Carrington Harrod"; Give the java statement that will convert String, to all upper case storing result into result1
int stringSize; stringSize = firstString.length(); S.o.p (" The name 'Carrington Harrod' has ) + stringSize + " characters"); result = The name Carrington Harrod has 17 characters
String firstString = "Carrington Harrod"; give a java statement that will print out the length of a string in firstString and store the result into a variable stringSize
import java.util.Scanner;
Write a java statement to import the scanner class (this is placed before the class header
newline, tab
\n \t