預設方法的基本用法
/**
* Interface with default method
*/
public interface Printable {
default void printString() {
System.out.println( "default implementation" );
}
}
/**
* Class which falls back to default implementation of {@link #printString()}
*/
public class WithDefault
implements Printable
{
}
/**
* Custom implementation of {@link #printString()}
*/
public class OverrideDefault
implements Printable {
@Override
public void printString() {
System.out.println( "overridden implementation" );
}
}
以下陳述
new WithDefault().printString();
new OverrideDefault().printString();
會產生這樣的輸出:
default implementation
overridden implementation