善待，我正在学习。
我正在创建一个地址簿，我需要添加名称才能进入arraylist。我遇到的问题是在arraylist中修改，删除和列出所有内容。我该怎么做？
这是我的班级文件：
import java.text.SimpleDateFormat;
import java.text.DecimalFormat;
import java.util.*;
public class AddressBook {
private static int totalNumber;
public static int getTotal() {
//Returns total number of employees
return totalNumber;
}
private Date lastModified;
private String fullname;
private String address;
private String city;
private String state;
private String zip;
private String phone;
public AddressBook() {
super();
}
/*public AddressBook(Date lastModified, String fullname, String address, String city, String state, String zip, String phone, int month, int day, int year) {
this.fullname = fullname;
this.address = address;
this.city = city;
this.state = state;
this.zip = zip;
this.phone = phone;
GregorianCalendar calendar = new GregorianCalendar(year, month-1, day );
this.lastModified = calendar.getTime();
}*/
public AddressBook(String fullname, String address, String city, String state, String zip, String phone) {
this.fullname = fullname;
this.address = address;
this.city = city;
this.state = state;
this.zip = zip;
this.phone = phone;
}
public Date getLastModified() {
return lastModified;
}
public void setLastModified(int month, int day, int year) {
month = 00;
day = 00;
year = 0000;
return;
}
public String getFullname() {
return fullname;
}
public void setFullname(String fullname) {
this.fullname = fullname;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getZip() {
return zip;
}
public void setZip(String zip) {
this.zip = zip;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
@Override
public String toString() {
return "Employee [name=" + this.fullname + ", Address=" + this.address + ", City="
+ this.city + ", state=" + this.state + ", zip=" + this.zip
+ ", phone=" + this.phone + "]";
}
}
这是测试文件：
import java.util.*;
public class testAddressBook {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
boolean switcher = true;
do {
System.out.println("\n\tAddress Book Menu");
System.out.println("\n\t\tEnter A to (A)dd Person ");
System.out.println("\t\tEnter D to (D)elete Person");
System.out.println("\t\tEnter M to (M)odify Person");
System.out.println("\t\tEnter S to (S)earch Address Book ");
System.out.println("\t\tEnter L to (L)ist ALL (sorted) ");
System.out.println("\t\tEnter Q to Quit");
System.out.print("\n\tPlease enter your choice: ");
char choice = sc.nextLine().toUpperCase().charAt(0);
while ((choice != 'A') && (choice != 'D') && (choice != 'M') && (choice != 'S') && (choice != 'L')&& (choice != 'Q')) {
System.out.println("Invalid choice! Please select (A)dd, (D)elete, (M)odify, (S)earch, (L)ist or (Q)uit: ");
choice = sc.nextLine().toUpperCase().charAt(0);
}
AddressBook newPerson = new AddressBook();
ArrayList<AddressBook> person = new ArrayList<>();
switch (choice) {
case 'A' :
System.out.println("\nTo add a person, follow the prompts.");
System.out.print("\nEnter Fullname: ");
newPerson.setFullname(sc.nextLine());
System.out.print("Enter Address: ");
newPerson.setAddress(sc.nextLine());
System.out.print("Enter City: ");
newPerson.setCity(sc.nextLine());
System.out.print("Enter State: ");
newPerson.setState(sc.nextLine());
System.out.print("Enter Zip: ");
newPerson.setZip(sc.nextLine());
System.out.print("Enter Phone Number: ");
newPerson.setPhone(sc.nextLine());
person.add(new AddressBook(newPerson.getFullname(), newPerson.getAddress(), newPerson.getCity(), newPerson.getState(), newPerson.getZip(), newPerson.getPhone()));
System.out.println(person.get(0));
System.out.println("\nYou have successfully added a new person!");
break;
case 'D' :
break;
case 'M' :
break;
case 'S' :
break;
case 'L' :
break;
case 'Q' :
switcher = false;
System.exit(0);
break;
default:
}
}
while (switcher != false);
}}
答案 0 :(得分：1)
这是您的ArrayList java doc。
以下是for-loop
的一些信息看看。
get()
add()
remove()
person.get(0)实际上是您的AddressBook对象。您将能够使用
希望这能提供足够的提示让你入门。
初学者提示：请记住保持步伐小。一旦您能够创建单个条目，请修改，然后将其删除。做两个。注意重复的代码......然后使用循环
对其进行编程到目前为止您遇到的一些错误：
AddressBook newPerson = new AddressBook();
ArrayList<AddressBook> person = new ArrayList<>();
// ... adding values to your newPerson
person.add(new AddressBook(newPerson.getFullname(), newPerson.getAddress(), newPerson.getCity(), newPerson.getState(), newPerson.getZip(), newPerson.getPhone()));
你正在填充你的人。然后创建一个具有相同人口值的新人。你可以简单地将原来的人传递给arraylist
person.add(newPerson);
答案 1 :(得分：0)
您有多个建议：
ArrayList<AddressBook>应该已命名为listOfAddressBook等。AddressBook对象添加到列表中：我的意思是：
person.add(newPerson)而不是person.add(new AddressBook(newPerson.getFullname(), newPerson.getAddress(), newPerson.getCity(), newPerson.getState(), newPerson.getZip(), newPerson.getPhone()));并且再次出现混淆，即对象属于AddressBook类型，但名称为newPerson。List<AddressBook> person = new ArrayList<>();所以去找出为什么这比你的方法更好。