java - abstract inner class + generics
Simple inner class usage:
public class OuterClass {
public OuterClass() {
}
public abstract class InnerAbstractClass {
public void a() {
}
public abstract void absMethod();
}
public void test() {
new OuterClass().new InnerAbstractClass() {
public void absMethod() {
}
};
}
public static void main(String[] args) {
new OuterClass().new InnerAbstractClass() {
public void absMethod() {
}
};
}
}Add generics to the above example
public class OuterClass<T> {
public OuterClass() {
}
public abstract class InnerAbstractClass {
public void a() {
}
public abstract void absMethod();
}
public void test() {
new OuterClass().new InnerAbstractClass() {
public void absMethod() {
}
};
}
public static void main(String[] args) {
new OuterClass().new InnerAbstractClass() {
public void absMethod() {
}
};
}
}Call the inner class in the test method and compile correctly. An error is reported in the main method, cannot be referenced from a static context.
No error will be reported if an internal class is called in another newly created class
public class OuterClassTest {
public static void main(String[] args) {
new OuterClass().new InnerAbstractClass() {
public void absMethod() {
}
};
}
}Why? ? ?
