java - Indexes of all occurrences of character in a string -

the following code print 2

string word = "bannanas"; string guess = "n"; int index; system.out.println(      index = word.indexof(guess) ); 

i know how indexes of "n" ("guess") in string "bannanas"

the expected result be: [2,3,5]

this should print list of positions without -1 @ end peter lawrey's solution has had.

int index = word.indexof(guess); while (index >= 0) {     system.out.println(index);     index = word.indexof(guess, index + 1); } 

it can done for loop:

for (int index = word.indexof(guess);      index >= 0;      index = word.indexof(guess, index + 1)) {     system.out.println(index); } 

[note: if guess can longer single character, possible, analyzing guess string, loop through word faster above loops do. benchmark such approach boyer-moore algorithm. however, conditions favor using such approach not seem present.]