// DrJava saved history v2
7 * 2.4 / 3 
// Variable: a name with an associated type and value
int karen;
karen = 7;
karen
karen = 10;
karen
// Variable declaration: <type> <name>;
// Variable initialization: <name> = <value>;
// We can do both declaration and initialization in a single statement:
double shelly = 8.34;
// Can't reuse a variable name!
int shelly;
double shelly2 = 8.34;
int x int y;
int x; int y;
// semi-colon signals the end of a statement
// variable declarations and assignments are statements (not expressions!)
8 / 5.2
shelly2 = true
shelly2
shelly2 = 9
shelly2 = (double) 9
// the int 9 is converted to a double
shelly2 = 9 * 3.5 / 3
// Assignment statement:
// 1. evaluate the expression on the right hand side
// 2. store the result in the variable on the left hand side
x
x = 12;
x + shelly2
x
shelly2
shelly2 = x + shelly2
shelly2
shelly2 > 20
shelly2 < 20
shelly2 >= 20
shelly2 <= 20
shelly2 == 20
// == is the comparision operator
3 != 8
3 != 3
// != is the "not equal" operator
true && 7 <= 9
// relational operators (>, <, >=, <=, ==, !=) have higher precedence than boolean operators (!, &&, ||)
3 + 9 < 4 * 2
// arithmetic operators have higher precedence than relational operators
x
boolean X;
X = true;
true || X
boolean kaRen;
// Java is case-sensitive: capitalization matters!
import javax.swing.JFrame;
JFrame j1;
j1 = new JFrame();
j1.show()
j1.show()
// the statement is a called a "method call"
j1.hide()
j1.show()
j1.hide()
j1.show()
j1.setTitle("This is the title of my window");
j1.setSize(200, 500);
j1.setLocation(0,0)
j1.setLocation(700,0)
j1.show()
j1.getTitle()
j1.setTitile("It is Friday");
j1.setTitle();
j1.setTitle("It is Friday");
j2.getX()
j1.getX()
j1.getX();
j1.getX()
j1.getY()
int p;
j1.setSize(444, 444)