String Methods - Java

isEmpty()

Returns true if the string is empty, otherwise false.

toUpperCase()

Returns a new string in uppercase.

toLowerCase()

Returns a new string in lowercase.

startsWith(prefix)

Returns true if the string starts with the given string prefix, otherwise false.

endsWith(suffix)

Returns true if the string ends with the given string suffix, otherwise false.

contains(…)

Returns true if the string contains the given string or character.

substring(beginIndex, endIndex)

Returns a substring of the string in the range: beginIndex to endIndex - 1.

replace(old, new)

Returns a new string obtained by replacing all occurrences of old with new (chars or strings).

replaceAll(old, new)

Returns a new string obtained by replacing all occurrences of old with new, where old is a regular expression.

trim()

Returns a copy of the string with leading and trailing whitespace omitted (spaces, tabs, newlines, etc.).