Benötigen Sie Hilfe Drucken Fahrzeug/Besitzer Daten in Java-Programm

Question

Ich habe eine Projektklasse. Eine Fahrzeugklasse. Eine Eigentümerklasse. Und eine Sammelklasse. Dieses Projekt benötigt Befehlszeilenargumente, aber keine Sorge, dass sie korrekt sind.

Die Collection-Klasse hat 5 Sortiermethoden, über die ich mich jetzt nicht kümmern muss. Ich brauche Hilfe beim Ausdrucken einer UNSORTED-formatierten Liste von Fahrzeuginformationen.

Die Klasse Besitzer wirft mir einen Fehler in Zeile 80. Die getVehicle() -Methode. Ich bin mir nicht sicher, wie diese Methode die Information sammelt! Könnte mich jemand aufklären?

package project5; 

/** 
* Provides the properties and methods for an owner. 
*/ 
public class Owner { 
    private static final String ROW = "%-12s%-12s%-49s%-17s%-41s"; 
    private static final String ADDRESS = "%s %s, %s %s"; 

// Owner properties 
    private String address; 
    private String city; 
    private String firstName; 
    private String lastName; 
    private String phone; 
    private String state; 
    Vehicle[] vehicle; 

    private String zip; 

/** 
* Creates an object instance of the Owner class. 
* @param ownerData The data representing the owner being stored. 
*/ 
protected Owner(String[] ownerData) { 
    lastName = ownerData[0]; 
    firstName = ownerData[1]; 
    address = ownerData[2]; 
    city = ownerData[3]; 
    state = ownerData[4]; 
    zip = ownerData[5]; 
    phone = ownerData[6]; 
    //vehicle = ownerData[7]; 
} 





/** 
* Returns the city of the owner. 
* @return the city of the owner. 
*/ 
public String getCity() { 
    return city; 
} 

/** 
* Returns a formatted String containing the header for an owner report. 
* @return a formatted String containing the header for an owner report. 
*/ 
public String getHeader() { 
    return String.format("%-12s%-12s%-49s%-17s%-12s%-16s%-6s%-7s\n%-12s%-12s%-49s%-17s%-12s%-16s%-6s%-7s", 
      "Last Name", "First Name", "Address", "Phone", "Make", "Model", "Year", "Mileage", 
      "---------", "----------", "-------", "-----", "----", "-----", "----", "-------"); 
} 

/** 
* Returns the last name of the owner. 
* @return the last name of the owner. 
*/ 
public String getLastName() { 
    return lastName; 
} 

/** 
* Returns the state of the owner. 
* @return the state of the owner. 
*/ 
public String getState() { 
    return state; 
} 

/** 
* Returns the vehicle of the owner. 
* @return the vehicle of the owner. 
*/ 
public Vehicle getVehicle() { 

return vehicle; //This method won't return 
} 

/** 
* Returns a formatted String containing information about this owner. 
* @return a formatted String containing information about this owner. 
*/ 
@Override 
public String toString() { 
    return String.format(ROW, lastName, firstName, String.format(ADDRESS, address, city, state, zip), phone, vehicle.toString()); 
} 

}

Dies ist die Fahrzeugklasse. Keine Fehler werfen.

package project5; 

/** 
* Provides the properties and methods for a vehicle. 
*/ 
public class Vehicle { 
    private static final String ROW = "%-12s%-16s%-6d%7d";  

// Vehicle properties 
private String make; 
private int mileage; 
private String model; 
private int year; 

/** 
* Creates an object instance of the Vehicle class. 
* @param vehicleData The data representing the vehicle being stored. 
*/ 
public Vehicle(String[] vehicleData) { 
    make = vehicleData[7]; 
    model = vehicleData[8]; 
    year = Integer.parseInt(vehicleData[9]); 
    mileage = Integer.parseInt(vehicleData[10]); 

} 

/** 
* Returns the mileage of the vehicle. 
* @return the mileage of the vehicle. 
*/ 
public int getMileage() { 
    return mileage; 
} 

/** 
* Returns a formatted String containing information about this vehicle. 
* @return a formatted String containing information about this vehicle. 
*/ 
@Override 
public String toString() { 
    return String.format(ROW, make, model, year, mileage); 
} 

/** 
* Returns the year of the vehicle. 
* @return the year of the vehicle. 
*/ 
public int getYear() { 
    return year; 
} 

} Dies ist meine ungebrauchte Sammlung Klasse. Wenn es ausgeführt wird, sollte es unsortierte Informationen anzeigen. (Die Sortiermethoden Ohne Berücksichtigung)

package project5; 

/** 
* Provides the properties and methods for a collection of owners. 
*/ 
public class Collection { 
// Sorting descriptions 
public static final int CITY_STATE = 0; 
public static final int LAST_NAME = 1; 
public static final int MILEAGE = 2; 
public static final int UNSORTED = 3; 
public static final int YEAR = 4; 

private int numOwners; 

private Owner[] owners; 
private String[] sortTypes = new String[] {"Sorted by City and State", "Sorted by Last Name", "Sorted by Mileage", "Unsorted", "Sorted by Year"}; 

/** 
* Creates an object instance of the Collection class and initializes the owner collection. 
* @param maxSize The maximum number of owners stored in this collection. 
*/ 
public Collection(int maxSize) { 
    owners = new Owner[maxSize]; 
} 

/** 
* Adds a owner to the collection. 
* @param owner The owner to add. 
*/ 
public void add(Owner owner) { 
    owners[numOwners++] = owner; 
} 

/** 
* Displays information about the owners and the vehicles they own. 
*/ 
public void displayOwners() { 
    displayOwners(sortTypes[UNSORTED]); 
} 

/** 
* Displays information about the owners and the vehicles they own. 
* 
* @param sortType The description of the sort performed on the owner data. 
*/ 
private void displayOwners(String sortType) { 
    System.out.format("\nOwner Information (%s):\n\n",sortType); 
    System.out.println(owners[0].getHeader()); 
    for (Owner owner : owners) { 
     System.out.println(owner.toString()); 
    } 
} 

/** 
* Returns the total number of owners stored in this collection. 
* @return the total number of owners stored in this collection. 
*/ 
public int getTotal() { 
    return owners.length; 
} 

/** 
* Determines which sorting method to call based on the specified sort type. 
* 
* Note: Once the data is sorted, this method displays the owner information. 
* 
* @param sortType The type of sort to perform. 
*/ 
public void sortData(int sortType) { 
    switch(sortType) { 
     case 0: // City and State 
      sortByOwnerCityState(); 
      break; 
     case 1: // Last Name 
      sortByOwnerLastName(); 
      break; 
     case 2: // Mileage 
      sortByVehicleMileage(); 
      break; 
     case 3: // Unsorted 
      break; 
     case 4: // Year 
      sortByVehicleYear(); 
      break; 
     default: 
      System.out.println("Error: Illegal Sort Type Selected"); 
    } 
    displayOwners(sortTypes[sortType]); 
} 

/** 
* Sorts the owner data by State, and then by City using the Bubble Sort algorithm. 
*/ 
private void sortByOwnerCityState() { 
    /* False Data Generator 
     for (traversal loop) 
      for (comparision 
       if (a[x].state compareTo(a[x+1]state)>0) 
        swap(x,x+1); 

    else if (a[x].state.compareTo(a[x+1]state)==0) && 
      (a[x].city.CompareTo(a[x+1]state)>0) 
       swap(x,x+1); 
    */ 
} 

/** 
* Sorts the owner data by Last Name using the Bubble Sort algorithm. 
*/ 
private void sortByOwnerLastName() { 

} 

/** 
* Sorts the owner data by vehicle Mileage using the Bubble Sort algorithm. 
*/ 
private void sortByVehicleMileage() { 

} 

/** 
* Sorts the owner data by vehicle Year using the Bubble Sort algorithm. 
* 
* Note: The data must be sorted in descending order (newest to oldest). 
*/ 
private void sortByVehicleYear() { 

} 

/** 
* Swaps values between the two specified locations in an array. 
* @param pos1 The position of the first value to swap. 
* @param pos2 The position of the second value to swap. 
*/ 
private void swap(int pos1, int pos2) { 

} 
} 

Und mein Projekt Klasse

package project5; 

import java.io.BufferedReader; 
import java.io.FileNotFoundException; 
import java.io.FileReader; 
import java.io.IOException; 

/** 
    Manages owner information. 
*/ 
public class Project5 { 
    private static final int MAX_OWNERS = 50; 

    private Collection owners; 

public static void main(String[] args) { 
    System.out.println("Ima Java Programmer\nProject 5"); 

    // Creates an object of the Project5 class, calls the execute method, and 
    // passes the filename of the input file provided in the command-line arguments 
    new Project5().execute(args[0]); 
} 

/** 
* Creates an object instance of the Project5 class and initializes the owner collection. 
*/ 
public Project5() { 
    owners = new Collection(MAX_OWNERS); 
} 

/** 
* Controls the operation of the program. 
* @param filename The path and name of the input data file. 
*/ 
private void execute(String filename) { 
    readFile(filename); 
    owners.displayOwners(); 
    owners.sortData(Collection.LAST_NAME); 
    owners.sortData(Collection.MILEAGE); 
    owners.sortData(Collection.YEAR); 
    owners.sortData(Collection.CITY_STATE); 
} 

/** 
* Reads data from the specified input file into the program. 
* @param filename The path and name of the input data file. 
* @return false if an error occurred while reading the file; otherwise, true. 
*/ 
private void readFile(String filename) { 
    String line; 

    try { 
     BufferedReader br = new BufferedReader(new FileReader(filename)); 
     while((line = br.readLine()) != null) { 
      owners.add(new Owner(line.split(","))); 
     } 
    } 
    catch(FileNotFoundException fnfe) { 
     System.out.format("The program could not find the file: %s.\n", filename); 
    } 
    catch(IOException ioe) { 
     System.out.format("An error occurred while reading the file: %s.\n", filename); 
    } 
    catch(Exception ex) { 
     System.out.format("An unexpected error occurred. Error information: %s.\n", ex.getMessage()); 
    } 
} 

}

Answer 1

public Vehicle getVehicle() { 
    return vehicle; 
} 

vehicle ist ein Array. Die Signatur der Methode sollte sein:

public Vehicle[] getVehicle()