I keep getting this error when making a search method in my code to search through string. I have gone through alot of examples trying to fix this but I cant find any. Thank you for any help and advise you can give.
public class runNote {
public static void main(String[] args) {
// TODO Auto-generated method stub
Notebook note = new Notebook();
note.storeNote("happy");
note.storeNote("hello there");
note.storeNote("work at 5");
note.storeNote("BBQ Time");
note.storeNote("UNI!!!!");
note.storeNote("Dont miss lecture at 9:15");
System.out.println(note.numberOfNotes());
note.showNote(1);
note.searchNotes("hap");
}}
public class Notebook{
/**
* Perform any initialization that is required for the
* notebook.
*/
public Notebook()
{
notes = new ArrayList();
}
/**
* Store a new note into the notebook.
* @param note The note to be stored.
*/
public void storeNote(String note)
{
notes.add(note);
}
/**
* @return The number of notes currently in the notebook.
*/
public int numberOfNotes()
{
return notes.size();
}
/**
* A simple search engine to find the correct notes.
*/
public void searchNotes(String search){
for (String item : notes){
if (item.contains(search)){
System.out.println(item);
}
}
}
/**
* Show a note.
* @param noteNumber The number of the note to be shown.
*/
public void showNote(int noteNumber)
{
if(noteNumber < 0) {
// This is not a valid note number, so do nothing.
}
else if(noteNumber < numberOfNotes()) {
// This is a valid note number, so we can print it.
System.out.println(notes.get(noteNumber));
}
else {
// This is not a valid note number, so do nothing.
}
}
}
Add notes as a global variable to your class
public class Notebook{
ArrayList<String> notes = null;
....
}
In the constructor, do:
public Notebook()
{
notes = new ArrayList<String>();
}
You are having exception at this line :
for (String item : notes)
notes
is an ArrayList
declared as raw type, although i don't see the declaration i can see this line of initialization:
notes = new ArrayList();
which sees it's element as of type Object
You need to declare notes
with ArrayList<String>
type such as:
ArrayList<String> notes = new ArrayList<>();
try this: notes = new ArrayList<String>();
You don't declare the notes variable
public class Notebook{
private ArrayList<String> notes;
...
来源:https://stackoverflow.com/questions/20445428/type-mismatch-cannot-convert-from-element-type-object-to-string