Java-如何在不知道类名的情况下使用接口调用方法类
我是java新手,我想从实现的类调用方法类,接口不知道类名“ClassA”,只知道对象c,我有2个文件 文件(1)CobaInterface.javaJava-如何在不知道类名的情况下使用接口调用方法类,java,interface,Java,Interface,我是java新手,我想从实现的类调用方法类,接口不知道类名“ClassA”,只知道对象c,我有2个文件 文件(1)CobaInterface.java package cobainterface; public class CobaInterface { public static void main(String[] args) { ImplementedClass implementedClass = new ImplementedClass();
package cobainterface;
public class CobaInterface {
public static void main(String[] args) {
ImplementedClass implementedClass = new ImplementedClass();
ClassA clsA = new ClassA();
implementedClass.myMethodFromClassA(clsA);
}
}
class ClassA{
public Integer getTwo(){
return 2;
}
}
interface MyInterface {
public void myMethod();
//here interface
public void myMethodFromClassA(Object c);
}
文件(2):impmentedClass.java
package cobainterface;
public class ImplementedClass extends CobaInterface {
public void myMethodFromClassA(Object c) {
//System.out.println(c.getTwo()); <- wrong when call method c.getTwo()
}
}
包装协同界面;
公共类实现的类扩展了协同界面{
public void myMethodFromClassA(对象c){
//System.out.println(c.getTwo());您应该使用泛型类型,以便实现知道对象将是什么
interface MyInterface<T> {
public void myMethod();
//here interface
public void myMethodFromClassA(T c);
}
但是,您将失去类型安全的所有好处。您也可以进行强制转换-也许应该检查一下实例如果我完全忘记了,有几种方法可以更安全地进行强制转换。@ScaryWombat.notices.@darrenforsyth谢谢您的帮助,这打开了我对java的认识,,
package cobainterface;
public class ImplementedClass Implements MyInterface<ClassA> {
public void myMethodFromClassA(ClassA c) {
//System.out.println(c.getTwo()); <- wrong when call method c.getTwo()
}
}
class Scratch {
public static void main(String[] args) {
ImplementedClass implementedClass = new ImplementedClass();
ClassA clsA = new ClassA();
implementedClass.myMethodFromClassA(clsA);
}
}
class ImplementedClass implements MyInterface<ClassA> {
@Override
public void myMethod() {
}
@Override
public void myMethodFromClassA(ClassA c) {
System.out.println(c.getTwo());
}
}
class ClassA {
public Integer getTwo() {
return 2;
}
}
interface MyInterface<T> {
void myMethod();
void myMethodFromClassA(T c);
}
System.out.println((MyClass)c.getTwo());