如何将变量从main方法类转移到另一个类？

Question

Okay... in my main class, I ask the user to enter an input int value. Now I need to take this value to a different class to do some coding. How?

Code from main class:

neededValue = keyboard.nextInt();

object.methodName(xxxx, yyyy):

---

Code from a different method in a different class:

public void methodName(double xxxx, int yyyy) {

        int index;

        for (index = 0; index < array.length; index++) {
            xxxx = array[index].xxxx;
            if (xxxx > **neededValue**) {
                //some more code

            }

        }
    }

---

Lets say user input is 4, how can I transfer that "4" to other classes?

Answer 1

You need to pass neededValue as argument

neededValue = keyboard.nextInt();   
object.methodName(xxxx, yyyy,neededValue):

Then in methodName function

public void methodName(double xxxx, int yyyy, int neededValue) {

    int index;

    for (index = 0; index < array.length; index++) {
        xxxx = array[index].xxxx;
        if (xxxx > **neededValue**) {
            //some more code
        }
    }
}

Hope it helped.

Answer 2

From main:

neededValue = keyboard.nextInt();

object.methodName(xxxx, yyyy, neededValue):

From the class:

public void methodName(double xxxx, int yyyy, int neededValue){
    int index;

    for (index = 0; index < array.length; index++) {
        xxxx = array[index].xxxx;
        if (xxxx > **neededValue**) {
            //some more code
        }
    }
}

Answer 3

Add a parameter to your another class method and pass the value from your main class.. same as below:

class A{
...
neededValue = keyboard.nextInt();

DifferentClass object = new DifferentClass();
object.methodName(xxxx, yyyy, neededValue):
...
}

class DifferentClass{
public void methodName(double xxxx, int yyyy, int neededValue) {
...
}
}

Answer 4

1. You can pass the nextValue variable to the method directly, like:

object.methodName(xxxx, yyyy, nextValue)

2. or you can declare a int variable in the class A of object:

   int someValue;

and set it by constructor or setter

object = new A(nextValue);
or object.setNextValue(nextValue)

then, your invoke object.methodName(xxxx, yyyy) will work with the 'someValue' field inside the object

Answer 5

Multiple ways to do it, few are listed below,

i) Create parameter in your method (explained in other solutions).

ii) Create a variable in your class with get/set methods in your class (explained in other solutions).

iii) Create a static variable in your class (explained below)

You can have a static variable in your class,

private static int neededValue;

And in your main, you can assign the value for it.

ClassName.neededValue = keyboard.nextInt();

object.methodName(xxxx, yyyy):

And you can use directly in your class method,

public void methodName(double xxxx, int yyyy){
int index;

for (index = 0; index < array.length; index++) {
    xxxx = array[index].xxxx;
    if (xxxx > ClassName.neededValue) {
        //some more code
    }
 }
}

Disclaimer: Know more about static keyword before using it.