用Java打印对象数组

我正在制作电话簿并填写条目。 这些条目包括两个姓氏和姓名字符串以及一个电话号码。 我正在使用数组来存储条目。 我正在尝试将数组打印出来，并且我在每个类中都添加了toString方法。 但是当我打印出来时，我仍然得到“[LEntry; @ 8dc8569”。 我不确定我做错了什么。 这是代码。

public class Entry { String surname; String initial; int number; public Entry(String surname, String initial, int number) { this.surname = surname; this.initial = initial; this.number = number; } public String getSurname(){ return surname; } public String getInitial(){ return initial; } public int getNumber() { return number; } void setNumber(int number){ this.number = number; } public String toString(){ return surname+ "\t" +initial+ "\t" +number; } } public class ArrayDirectory { int DIRECTORY_SIZE = 6; Entry [] directory = new Entry[DIRECTORY_SIZE]; public void addEntry(String surname, String initial, int num) { int i = findFreeLocation(); directory[i] = new Entry(surname, initial, num); } public void deleteEntry(String surname, String initial) { int i = findEntryIndex(surname, initial); directory[i] = null; } public void deleteEntry(int number) { int i = findEntryIndex(number); directory[i] = null; } public int findEntry(String surname, String initial) { int i; i = findEntryIndex(surname, initial); return directory[i].getNumber(); } public void editNum(String surname, String initial, int number) { int i; i = findEntryIndex(surname, initial); directory[i].setNumber(number); } public void print() { // TODO print array System.out.println(directory); } private int findEntryIndex(String surname, String initial) { int i; for (i = 0; i <= DIRECTORY_SIZE; i++) { if(directory[i] != null && directory[i].getSurname().equals(surname) && directory[i].getInitial().equals(initial)) { break; } } return i; } private int findEntryIndex(int number) { int i; for (i = 0; i <= DIRECTORY_SIZE; i++) { if(directory[i] != null && directory[i].getNumber() == number) { break; } } return i; } private int findFreeLocation() { int i; for (i = 0; i < DIRECTORY_SIZE; i++) { if(directory[i] == null) { break; } } return i; } public String toString() { for(int i = 0 ; i< DIRECTORY_SIZE ; i++){ System.out.println( directory[i] ); } return null; } } public class Test { public static void main(String[] args) { ArrayDirectory phoneBook = new ArrayDirectory(); phoneBook.addEntry("Bigger", "R", 2486); phoneBook.addEntry("Smaller", "E", 0423); phoneBook.addEntry("Ringer", "J", 6589); phoneBook.addEntry("Looper", "T", 6723); phoneBook.addEntry("Lennon", "B", 4893); phoneBook.addEntry("Martin", "M", 2121); phoneBook.print(); } } 

Answer 1

使用Arrays.toString();

 Arrays.toString(directory); 

当你只是打印directory ，这是一个类型为Entry的数组的实例，它不会像你期望的那样覆盖toString()方法

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另见

• 为什么没有java.lang.Array类？ 如果java数组是一个Object，它不应该扩展Object吗？