将字符串数组从一类传递到另一类

Question

I'm trying to pass a string array from one class to another in my java code. By using code such as

Class instanceofclass = new Class();
String text1 = instanceofclass.variablename;

and then displaying it out on screen worked fine!

However I'm trying to get the array of a string. So in my first class I have

JButton [] FilmTime = new JButton[5];                       
JButton [] FilmNames = new JButton[8];
String [] films = new String [8];
DbConnector dataBase = new DbConnector();
for (int i =0; i <= 7; i++)
        {
            films[i] = dataBase.FilmTitle[i];
        }
    for (int i =0; i<= 7; i++)
        {
            FilmNames[i] = new JButton (films[i] + " ("+age+")");
            FilmNames[i].setPreferredSize(new Dimension(563,50));

            grid.add(FilmNames[i]);
        }

I know I can use one for loop but I was just checking issues at the momment.

In my second class used named dbconnector i have:

public String FilmTitle [];
    for (int i =0; i<=7; i++)
                {
                    String query = "SELECT * FROM films WHERE ID =" + i;
                    Rs = St.executeQuery(query);
                        while (Rs.next())
                        {   
                            FilmTitle[i] = Rs.getString("FilmName");

                        }
                }

Eclipse gives the error as:

Error is: java.lang.NullPointerException
java.lang.NullPointerException
    at main.init(main.java:46)
    at sun.applet.AppletPanel.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

Line 46 is the statement in the first for loop... testingme[i] = instanceofclass.variablename[i];

Answer 1

您必须初始化字符串数组。

String[] testingme = new String[8];