Strings and Regular Expressions - The Java Programming Language - page 462

public String replace(char oldChar, char newChar)

Returns a String with all instances of oldChar replaced with the
character newChar .

public String replace(CharSequence oldSeq, CharSquence newSeq)

Returns a String with each occurrence of the subsequence
oldSeq replaced by the subsequence newSeq .

public String trim()

Returns a String with leading and trailing whitespace stripped.
Whitespace characters are those identified as such by the
Character.isWhitespace method and include space, tab, and
newline.

A number of methods return related strings based on a match with
a given regular expressionsee " Regular Expression Matching " on page
321 :

public String replaceFirst(String regex, String repStr)

Returns a String with the first substring that matches the
regular expression regex replaced by repStr . Invoked on str ,
this

is equivalent to

Pat-

tern.compile(regex).matcher(str).replaceFirst(repStr) .

public String replaceAll(String regex, String repStr)

Returns a String with all substrings that match the regular
expression regex replaced by repStr . Invoked on str , this
is equivalent to

Pat-

tern.compile(regex).matcher(str).replaceAll(repStr) .

public String[] split(String regex)