Primitive data types and Strings

Primitive data types:

int An integer number. -2147483648 to 2147483647
float: approximately from -2billion to 2 billion (3.4028235 X 10 ^38)
double: 2.2250738585072014 X 10 ^(-308) to 1.797693134862315570e ^(+308) BiG!
boolean: true or false
char: one character only

More information in primitive data types, in pages 44-46 of your book.

String

This is not a primitive data type, It is an object, it is special and different object. It is a set of char (primitive data types) put together. There are plenty of uses for strings. We will use it for our first assignment.

Our first JAVA program

 import java.io.*;

class FirstProgram{
  public static void main (String[] arg){
     String name = "Blanca";
     System.out.println(name);
  } //closes the main method
} //closes the class

String methods

What methods does the String class provide?
What methods does the String class provide?

Follow the form: objectReference.method-name(arguments)

METHOD RETURNS ARGUMENTS

toUpperCase reference to a String object none

toLowerCase reference to a String object none

length an integer number none

trim reference to a String object none

concat reference to a String object reference to a String object

substring reference to a String object a number (position to start)

substring reference to a String object two numbers (positions to start and end)

METHOD	RETURNS	ARGUMENTS
toUpperCase	reference to a String object	none
toLowerCase	reference to a String object	none
length	an integer number	none
trim	reference to a String object	none
concat	reference to a String object	reference to a String object
substring	reference to a String object	a number (position to start)
substring	reference to a String object	two numbers (positions to start and end)