如何从另一个类中的一个Java类调用变量

Question

I ran into an issue, where I need to call a variable created in one java class in another java class.

Course.java

public class Course {
   public String courseName;

SecondCourse.java

    public class SecondCourse {
        Course courseName;

@Before
    public void setUp() throws Exception {
        courseName = new Course();

Eventhough, I have set up it like this, the varible call doesn't work in SecondCourse.java Class. Have I missed something? Can you help me?

I'm trying to call

driver.findElement(By.xpath("//div/input")).sendKeys(courseName); 

in the SecondCourse.java class. But gives me the error sendKeys(java.lang.CharSequence...) in org.openqa.selenium.WebElement cannot be applied

Answer 1

First of all you define in your Course.java class

public class Course
{
    public static String courseName; //Define variable as static here
 }

Access that variable in any class using class name

Course.courseName = "abc"; // /Access this variable 

Answer 2

Course courseName of SecondCourse defines a member field of type Course - it does not correspond to String courseName of Course . You can, if you want, access the courseName string of the Course object stored in courseName Course of SecondCourse using courseName.courseName .

Answer 3

Simply In SecondCourse.java

       public class SecondCourse {
            Course obj = new Course(); // creates new obj for Course class

    @Before
        public void setUp() throws Exception {
            //courseName = new Course(); //You won't need this.
        system.out.println("Here is how your obj can be called "+ obj.courseName);
}

Answer 4

Not 100% sure what your overall goal is, but this might prove helpful.

public class Course {
    private String courseName;

    public Course(String courseName) {
        this.courseName=courseName;
    }

    public String getCourseName() {
        return this.courseName;
    }
}

public class SecondCourse {
    private Course course;

    public SecondCourse(String courseName) {
        course=new Course(courseName);
    }

    public void setup() {
        String courseName=course.getCourseName();
        /*
         * Do something with courseName
         */
    }
}

The Course class initialize and grants access to it's courseName variable and the Second Course does additional work on the course using the functionality given by the Course class.

In addition this post on encapsulation may prove useful.

Answer 5

Use Course.courseName , u will be able to access the other class variable. Hope it helps. Thanks.