java - 如何在java中从 'null'更改字符串中的占位符文本

Question

我的代码按照我想要的方式编译和运行，但是，我有一个问题，在我在日历中添加事件后，除非那天有特定事件，否则终端的结果显示每天都没有结果，结果是“空”，我想知道是否有任何方法可以改变它

public class Calendar {
public static void main(String[] args) {

    String[] calender = new String[32];
    String ans = " ";

    do {
        System.out.print("Type the number day of your event: ");
        int date = IO.readInt();
        System.out.println("What is the event?");
        String event = IO.readString();
        System.out.println("Do you have another event to add? y/n: ");
        addEvent(calender, event, date);
        ans = IO.readString();
    } while (ans.equals("y"));

    printCal(calender);


}

public static void addEvent(String[] calender, String event, int date) {

    calender[date] = event;

    // return true;

}

public static void printCal(String[] calender) {
    for (int i=1;i<calender.length;i++) {
        System.out.println("Day: " + i + " " + " Event: " + calender[i]);
    }
}

}

Answer 1

打印时您可以检查它是否为空，如果是，则打印其他内容。在这种情况下，它将打印“Holding Text”而不是 null。请随意将其更改为您想要的任何内容。

public static void printCal(String[] calender) {
    for (int i=1;i<calender.length;i++) {
        String event = (calendar[i] == null) ? "Holding Text" : calendar[i];
        System.out.println("Day: " + i + " " + " Event: " + event);
    }
}