Массив объектов и toString

Question

Я собираюсь включить то, что у меня есть.

import java.util.Scanner; 

// Creates a class called presidents 
public class presidents3{ 
    // Initilaizes an object called input using the Scanner that is public. 
    public static Scanner input = new Scanner(System.in); 
    // Initializes a public static String variable called strInfo. 
    public static String strInfo; 
    // Initializes a public int variables number. 
    public static int number; 
    // Creates a main method that doesn't return anything. 
    public static void main(String[] args){ 
     // Initilaizes a String multidimensional array that holds the information about the presidents. 
     String presidents[][] = { 
     {"1 ","George"," ","Washington"," (1789-1797) ","John Adams"}, 
     {"2 ","John"," ","Adams"," (1797-1801) ","Thomas Jefferson"}, 
     {"3 ","Thomas"," ","Jefferson"," (1801-1809) ","Aaron Burr"}, 
     {"4 ","James"," ","Madison"," (1809-1817) ","George Clinton"}, 
     {"5 ","James"," ","Monroe"," (1817-1825) ","Daniel D. Tompkins"}, 
     {"6 ","John"," Quincy ","Adams"," (1825-1829) ","John C. Calhoun"}, 
     {"7 ","Andrew"," ","Jackson"," (1829-1837) ","John C. Calhoun"}, 
     {"8 ","Martin"," Van ","Buren"," (1837-1841) ","Richard M. Johnson"}, 
     {"9 ","William"," Henry ","Harrison"," (1841) ","John Tyler"}, 
     {"10 ","John"," ","Tyler"," (1841-1845) ","None"}, 
     {"11 ","James"," K. ","Polk"," (1845-1849) ","George M. Dallas"}, 
     {"12 ","Zachary"," ","Taylor"," (1849-1850) ","Millard Fillmore"}, 
     {"13 ","Millard"," ","Fillmore"," (1850-1853) ","None"}, 
     {"14 ","Franklin"," ","Pierce"," (1853-1857) ","William King"}, 
     {"15 ","James"," ","Buchanan"," (1857-1861) ","John C. Breckinridge"}, 
     {"16 ","Abraham"," ","Lincoln"," (1861-1865) ","Hannibal Hamlin"}, 
     {"17 ","Andrew"," ","Johnson"," (1865-1869) ","None"}, 
     {"18 ","Ulysses"," S. ","Grant"," (1869-1877) ","Schuyler Colfax"}, 
     {"19 ","Rutherford"," B. ","Hayes"," (1877-1881) ","William Wheeler"}, 
     {"20 ","James"," A. ","Garfield"," (1881) ","Chester Arthur"}, 
     {"21 ","Chester"," ","Arthur"," (1881-1885) ","None"}, 
     {"22 ","Grover"," ","Cleveland"," (1885-1889) ","Thomas Hendricks"}, 
     {"23 ","Benjamin"," ","Harrison"," (1889-1893) ","Levi P. Morton"}, 
     {"24 ","Grover"," ","Cleveland"," (1893-1897) ","Adlai E. Stevenson"}, 
     {"25 ","William"," ","McKinley"," (1897-1901) ","Garret Hobart"}, 
     {"26 ","Theodore"," ","Roosevelt"," (1901-1909) ","None"}, 
     {"27 ","William"," Howard ","Taft"," (1909-1913) ","James S. Sherman"}, 
     {"28 ","Woodrow"," ","Wilson"," (1913-1921) ","Thomas R. Marshall"}, 
     {"29 ","Warren"," G. ","Harding"," (1921-1923) ","Calvin Coolidge"}, 
     {"30 ","Calvin"," ","Coolidge"," (1923-1929) ","None"}, 
     {"31 ","Herbert"," ","Hoover"," (1929-1933) ","Charles Curtis"}, 
     {"32 ","Franklin"," D. ","Roosevelt"," (1933-1945) ","John Nance Garner"}, 
     {"33 ","Harry"," S. ","Truman"," (1945-1953) ","None"}, 
     {"34 ","Dwight"," D. ","Eisenhower"," (1953-1961) ","Richard Nixon"}, 
     {"35 ","John"," F. ","Kennedy"," (1961-1963) ","Lyndon B. Johnson"}, 
     {"36 ","Lyndon"," B. ","Johnson"," (1963-1969) ","None"}, 
     {"37 ","Richard"," ","Nixon"," (1969-1974) ","Spiro Agnew"}, 
     {"38 ","Gerald"," ","Ford"," (1974-1977) ","Nelson Rockefeller"}, 
     {"39 ","Jimmy"," ","Carter"," (1977-1981) ","Walter Mondale"}, 
     {"40 ","Ronald"," ","Reagan"," (1981-1989) ","George Bush"}, 
     {"41 ","George"," ","Bush"," (1989-1993) ","Dan Quayle"}, 
     {"42 ","Bill"," ","Clinton"," (1993-2001) ","Al Gore"}, 
     {"43 ","George"," W. ","Bush"," (2001-2009) ","Dick Cheney"}, 
     {"44 ","Barack"," ","Obama"," (2009-2017) ","Joe Biden"}, 
     }; 
     President[] President = new President[44]; 
     // Welcomes user and asks for input which will appear on the same line that asks for your input. 
     System.out.println("This will display the President and VP of the United States based on the number you provide."); 
     System.out.print("Please enter a number between 1 and 44 to see information or q to quit: "); 
     strInfo = input.nextLine(); 
     // Creates a while loop and checks if the strInfo equals q. 
     while (!strInfo.equals("q")){ 
      // Calls the isInteger method and passes the strInfo and sees if strInfo can become an int. 
      if (isInteger(strInfo)){ 
       // If the boolean is true, number will be set to Integer.parseInt(strInfo) which converts the String to int. 
       number = Integer.parseInt(strInfo); 
       if (number >= 1 && number <= 44){ 
        // Prints out the information. 
        President President = new President ("1 ","George"," ","Washington"," (1789-1797) ","John Adams"); 
        System.out.println(); 
        System.out.println(Presidents.toString()); 
        System.out.println(); 
        // Asks for input once again 
        System.out.print("Please enter a number between 1 and 44 to see information or q to quit: "); 
        strInfo = input.nextLine(); 
       }else{ 
        // Asks for input once again when you have entered an invalid number. 
        System.out.println(); 
        System.out.print("Wrong Input! Please enter number 1-44 or q to quit: "); 
        strInfo = input.nextLine(); 
       } 
      }else{ 
       // Asks for input once again when you have entered an invalid number and a String that is not q. 
       System.out.println(); 
       System.out.print("Wrong Input! Please enter number 1-44 or q to quit: "); 
       strInfo = input.nextLine(); 
      } 
     } 
     // Happens after you input q. 
     System.out.println(); 
     System.out.println("This program has been terminated. Good Bye!"); 
    } 

    // Creates a boolean method isInteger that takes the strInfo and checks if it can become an integer. 
    public static boolean isInteger(String strInfo){ 
     // Attempts to convert strInfo to int and looks for something to catch. If it is null or not a number it will return false. 
     try{ 
      Integer.parseInt(strInfo); 
     }catch(NumberFormatException e){ 
      return false; 
     }catch(NullPointerException e){ 
      return false; 
     } 
     // If false wasn't returned at all during this method, true will be returned. 
     return true; 
    } 
} 

Другой класс:

public class President{ 
    String number; 
    String firstName; 
    String middleName; 
    String lastName; 
    String years; 
    String vicePresident; 

    public President(String num, String fName, String mName, String lName, String yrs, String vp){ 
     number = num; 
     firstName = fName; 
     middleName = mName; 
     lastName = lName; 
     years = yrs; 
     vicePresident = vp; 
    } 

    public String toString(){ 
     return String.format("Our %s was %s %s %s. /n He was in office from %s. /n His Vice President was %s.", this.number, this.firstName, this.middleName, this.lastName, this.years, this.vicePresident); 
    } 
} 

Вот что я пытаюсь сделать в рамках проекта. Мне было поручено сделать это в двух классах. Я пытаюсь создать массив объектов через конструктор, который содержит эту информацию из массива данных, которые у меня есть, с использованием метода toString(), чтобы правильно отформатировать его, чтобы сказать, что президент был президентом. Затем годы, а затем вице-президент. Я могу описать это по запросу. Я все еще нуждаюсь в этом, чтобы отработать вход и все же отрицать все, что не является 1-44 или «q». Кто-нибудь есть идеи или знает, как это должно выглядеть или что мне не хватает, чтобы заставить его работать? Любая помощь будет принята с благодарностью.

Answer 1

Вот как вы можете создать массив объекта:

President[] presidents = new President[44]; 

Затем передать параметры.

presidents[0] = new President ("1 ","George"," ","Washington"," (1789-1797) ","John Adams"); 

или вы могли бы сделать что-то вроде этого:

for(int i=0;i<44;i++){ 

     presidents = new President(YourString[i][0],YourString[i][1],YourString[i][2],YourString[i][3],YourString[i][4]); 

}