从另一个班级打电话给班级

I want to call class2 from class1 but class2 doesn't have a main function to refer to like Class2.main(args);

我想从class1调用class2，但class2没有一个main函数来引用类似Class2.main（args）;

5 个解决方案

#1

Suposse you have

你有的

Class1

1类

public class Class1 {
    //Your class code above
}

Class2

等级2

public class Class2 {
}

and then you can use Class2 in different ways.

然后你可以用不同的方式使用Class2。

Class Field

类场

public class Class1{
    private Class2 class2 = new Class2();
}

Method field

方法字段

public class Class1 {
    public void loginAs(String username, String password)
    {
         Class2 class2 = new Class2();
         class2.invokeSomeMethod();
         //your actual code
    }
}

Static methods from Class2 Imagine this is your class2.

Class2中的静态方法想象一下这是你的class2。

public class Class2 {
     public static void doSomething(){
     }
}

from class1 you can use doSomething from Class2 whenever you want

从class1开始，你可以随时使用Class2中的doSomething

public class Class1 {
    public void loginAs(String username, String password)
    {
         Class2.doSomething();
         //your actual code
    }
}

#2

Simply create an instance of Class2 and call the desired method.

只需创建Class2的实例并调用所需的方法。

推荐阅读：http：//docs.oracle.com/javase/tutorial/java/javaOO/

#3

If your class2 looks like this having static members

如果你的class2看起来像这样有静态成员

public class2
{
    static int var = 1;

    public static void myMethod()
    {
      // some code

    }
}

Then you can simply call them like

然后你可以简单地称他们为

class2.myMethod();
class2.var = 1;

If you want to access non-static members then you would have to instantiate an object.

如果要访问非静态成员，则必须实例化对象。

class2 object = new class2();
object.myMethod();  // non static method
object.var = 1;     // non static variable

#4

First create an object of class2 in class1 and then use that object to call any function of class2 for example write this in class1

首先在class1中创建class2的对象，然后使用该对象调用class2的任何函数，例如在class1中编写它

class2 obj= new class2();
obj.thefunctioname(args);

#5

Class2 class2 = new Class2();

Instead of calling the main, perhaps you should call individual methods where and when you need them.

也许您应该在需要的地方和时间调用单独的方法，而不是调用main。

#1