我正在從Object的練習中首先用java進行自我檢查。我遇到麻煩的那部分練習是它要求我查找refNumber字符串的長度..如果字符串的長度爲零,則打印出一行說「zzz」的行。我已經嘗試通過使一個局部變量,並使其等於refNumber.length()。但是,在我的條件聲明中,bluejay表明我有一個不兼容的類型。呃,請幫忙。提前致謝。使用.length方法時出現不兼容的類型
class Book
{
// The fields.
private String author;
private String title;
private int pages;
private String refNumber;
/**
* Set the author and title fields when this object
* is constructed.
*/
public Book(String bookAuthor, String bookTitle, int numberOfPages)
{
author = bookAuthor;
title = bookTitle;
numberOfPages = pages;
refNumber = "";
}
public String getAuthor()
{
return author;
}
public String getTitle()
{
return title;
}
public int getPages()
{
return pages;
}
public String getRefNumber()
{
return refNumber;
}
public void setRefNumber(String ref){
ref = refNumber;
}
public void printTitle() {
System.out.println("Book desciption: " + title);
}
public void printAuthor() {
System.out.print(" by " + author);
}
public void printPages(){
System.out.println("Pages: " + pages);
}
public void printRef(){
int count = refNumber.length();
if (count = 0){ //incompatible type wtf?
System.out.println("zzz");
}
else {
System.out.println("Reference Number: " + referenceNumber);
}
}
你不覺得你應該在'if'語句中比較'=='嗎? – 2013-02-28 06:50:04
謝謝你們的幫助,現在很清楚。 – 2013-02-28 06:55:28