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javapathio

How does the isAbsolute method run[Java]?

The isAbsolute method does not have a body in the path interface, but I can run it in the following code. How is this possible?

Path path= Paths.get("D:\\Example\\1.txt");
    System.out.println(path.isAbsolute());//prints true
Solution

  • Imagine following code:

    public interface Foo {
  public boolean bar();
}

public class Fooz implements Foo {
  @Override
  public boolean bar() {
    return false;
  }
}

    And:

    public Foo getFoo() {
  return new Fooz();
}

public static void main(String[] args) {
  Foo myFoo = getFoo();
  System.out.println(myFoo.bar()) //false
}

    If you are looking for actual implementation of this function, I advise looking thru the source code of JVM of your choosing. Example of one such implementation can be found in UnixPath.java on OpenJDK github repo.