java - 从类创建对象数组

Question

public class PostalCodes {
private String city;
private double latitude;
private double longitude;
private String zip;
private String state;

public PostalCodes(String aZip, String aCity, String aState, double aLatitude, double aLongitude)
{
    city = aCity;
    latitude = aLatitude;
    longitude = aLongitude;
    zip = aZip;
    state = aState;
}

void setZip(String aZip)
{
    zip=aZip;
}

void setState(String aState)
{
    state=aState;
}


void setLocation(String aCity)
{
    city = aCity.trim();
}
void setLatitude(double lat)
{
    latitude = lat;
}
void setLongitude(double long1)
{
    longitude = long1;
}
public String getState()
{
    return state;
}
public String getZip()
{
    return zip;
}
public String getLocation()
{
    return city;
}
public double getLatitude()
{
    return latitude;
}
public double getLongitude()
{
return longitude;
}
public String toString()
{
    String result = String.format("%s %s,%s (%1.3f; %1.3f)",zip, city, state, latitude,longitude);
    return result;
}

}上面是我的类，我正在尝试创建一个 50000 的数组，下面是我的主要...

public class Hmwk {

public static void main(String[] args) throws IOException {
    URL url = new URL("http://noynaert.net/zipcodes.txt");
    Scanner input=new Scanner (url.openStream());
    int counter =0;
    final int MAX_SIZE=50000;
    PostalCodes[] codesArray= new PostalCodes[50000];
    while (input.hasNextLine() && counter < MAX_SIZE)
    {
        String line=input.nextLine();
        String[] tokens;
        tokens = line.split("\t");
        if (tokens.length != 5)
        {
            continue;
        }
        String zip=tokens[0];
        String city=tokens[1];
        String state=tokens[2];
        double lat=Double.parseDouble(tokens[3]);
        double longy=Double.parseDouble(tokens[4]);
        PostalCodes code=new PostalCodes(zip,city,state,lat,longy);
        codesArray[counter]= code; //Error here
        //System.out.println(code.toString());
        counter++;
    }

                for (int i =0;i<counter; i+=1000)
    {
                  System.out.println(codesArray[i].toString());
    }
}

我正在尝试将前 50000 个条目保存为 095601 Amador City,CA (38.427; -120.828),095604 Auburn,CA (39.106; -120.536), 095605 West Sacramento,CA (38.592; -121.528) ) 等在我的数组中。我能够打印出我想要的格式，但我不知道如何将其添加到数组中。感谢您抽出时间。

Answer 1

您的代码试图将一个字符串添加到 PostalCodes 数组中，但您实际上想要添加一个 PostalCodes 对象。

删除对 toString() 的调用:

PostalCodes code = new PostalCodes(zip,city,state,lat,longy);
codesArray[counter] = code;

<小时/>

顺便说一句，我建议将您的类重命名为单数 PostalCode。