java - How to implement insertion sort to my ArrayList? -

i have homework problem i've been able easily, i'm stuck on how implement insertion sort arraylist i've constructed.

here's code far:

public class emaildirectory  {  public static void main(string[] args) {     new emaildirectory();               //relay main menu until 3 entered }  public arraylist<string> emailrecords=new arraylist<string>();  //construct array directory, array or arraylist?  public emaildirectory() {     scanner scnr=new scanner(system.in);    //scanner , empty string option choice     string menuchoice;      do{     //do while keep repeating         system.out.println("please enter number of option choice:");         system.out.println("1. add new contact");         system.out.println("2. search exsisting contact");         system.out.println("3. exit");         menuchoice=scnr.nextline();               if (menuchoice.equals("1"))     //add new contact                {                 addcontact();             }                 else if (menuchoice.equals("2"))    //search contacts             {                 searchcontact();             }       }     while(menuchoice.equals("3")==false); }  private void addcontact()    {     scanner addcont=new scanner(system.in);     //scanner new contact     string newcont;      system.out.println("please enter email adress.");   //prompt user     newcont=addcont.nextline();     emailrecords.add(newcont);                  //add array access later     insertionsort(emailrecords);  }  private void searchcontact()     {     //todo     system.out.println(emailrecords);           //test output, change laster }  public void insertionsort(arraylist<string> emailrecords)   //insertion sort, pass parameter? {         int i,j;     string key;     arraylist<string> inputarray=emailrecords;      (j=1; j<inputarray.size(); j++)          {             key = inputarray.get(j);             = j - 1;                 while (i >= 0)                 {                     if (key.compareto(inputarray.get(i)) > 0) {                     break;                 }              string element=inputarray.get(i+1);              element = inputarray.get(i);              i--;          }          string element=inputarray.get(i+1);          element = key;     }     } } 

the homework problem create email directory , keep sorted using insertion, cant seem figure out why array wont sort. im able add emails, when print out appends end.

suggestions , advise appreciated, much!

fix sort function this:

 public void insertionsort(arraylist<string> emailrecords)   //insertion sort, pass parameter?     {         int i,j;     string key;     arraylist<string> inputarray=emailrecords;      (j=1; j<inputarray.size(); j++)          {             key = inputarray.get(j);             = j - 1;                 while (i >= 0)                 {                     if (key.compareto(inputarray.get(i)) > 0) {                     break;                 }              string element=inputarray.get(i+1);             //here              inputarray.set(i+1,inputarray.get(i));          //here              inputarray.set(i,element);                      //here              i--;          }          key=inputarray.get(i+1);     }     } }