在我的代碼中搜索方法中搜索字符串時,我總是收到此錯誤。我已經通過很多例子來解決這個問題,但是我找不到任何例子。謝謝你的幫助,並建議你可以給。類型不匹配無法從元素類型對象轉換爲字符串
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.
}
}
}
什麼是錯誤? – hrv
粘貼確切完整的錯誤消息,並告訴我們它指向的是哪一行。 –
「筆記」聲明在哪裏?當你聲明它爲'ArrayList'時,你是否聲明它爲'ArrayList'? –