Java Summary - Building Java Programs: A Back to Basics Approach - page 1118

Useful Methods of Scanner Objects

Method Description

Reads and returns the next token as a String

next()

Reads and returns a double value

nextDouble()

Reads and returns an int value

nextInt()

Reads and returns the next line of input as a String

nextLine()

Returns true if there is another token to be read

hasNext()

Returns true if there is another token to be read and if it can be
interpreted as a double

hasNextDouble()

Returns true if there is another token to be read and if it can be
interpreted as an int

hasNextInt()

Returns true if there is another line of input to be read

hasNextLine()

Useful Methods of String Objects

Method Description Example (assuming s is "hello" )

Returns character at a specific

s.charAt(1) returns 'e' charAt(index)

index

Tests whether the string ends

s.endsWith("llo") returns endsWith(text)

with some text

true

Returns index of a particular

s.indexOf("o") returns 4 indexOf(text)

character or String ( -1
if not present)

Returns number of characters

s.length() returns 5 length()

in the string

Tests whether the string starts

s.startsWith("hi") returns startsWith(text)

with some text

false

substring(start, Returns characters from start s.substring(1, 3)

index to just before stop index returns "el"

stop)

Returns a new string with all

s.toLowerCase() returns toLowerCase()

lowercase letters

"hello"

Returns a new string with all

s.toUpperCase() returns toUpperCase()

uppercase letters

"HELLO"