Java将数组传递给构造函数

Question

I am new to Java and encountered this problem: I am learning how to save object state to a file and I got stuck with passing an array to the constructor. I believe that the problem is the base class with the constructor but I am not sure.

here is my Hero class:

import java.io.Serializable;


public class Hero implements Serializable{

/**
 * 
 */
private static final long serialVersionUID = 1L;

private int power;
private String type;
private String[] wepons;


public int getPower() {
    return power;
}


public void setPower(int power) {
    this.power = power;
}


public String getType() {
    return type;
}


public void setType(String type) {
    this.type = type;
}


public String[] getWepons() {
    return wepons;
}


public void setWepons(String[] wepons) {
    this.wepons = wepons;
}

public Hero(int powerH, String typeH, String[] weponsH) {
    this.power = powerH;
    this.type = typeH;
    this.wepons = weponsH;
}

}

and here is class which I try to use to save the object state:

import java.io.*;
public class SaveGame {

public static void main(String[] args) {

    Hero hero1 = new Hero(50, "Elf", new String[] {"bow", "short sword", "powder"});


    try{
        ObjectOutputStream os = new ObjectOutputStream(new FileOutputStream("Game.ser"));
        os.writeObject(hero1);
        os.close();
    } catch (IOException ex) {
        ex.printStackTrace();
    }

    ObjectInputStream is;

    try {
        is = new ObjectInputStream(new FileInputStream("Game.ser"));
        Hero p1N = (Hero) is.readObject();
        System.out.println(p1N.getPower() + " " + p1N.getType() + " " + p1N.getWepons());
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

}

Can you tell me and explain what am I doing wrong. Do I really need setters and getters in my Hero class and I have the feeling that I am using them incorrectly.

My problem was that when I tried to print out the Hero's parameters I got content of the array instead of string representation of the array. Thanks to user2336315 I know now that i should use Arrays.toString method when printing content of an array

Answer 1

I ran your code and everything seems to be fine. The only problem is that you want to print the content of the array itself, not the string representation of the array itself. So use Arrays.toString :

System.out.println(p1N.getPower() + " " + p1N.getType() + " " + Arrays.toString(p1N.getWepons()));

Output :

50 Elf [bow, short sword, powder]

Answer 2

Deserialization mechanism creates the class using its meta data. It does not depend on the access levels of the members of the target class, inclusing constructors. (Your code will work even Hero class has private default constructor.)