implsments

package study.itest;

public interface IOne {

 public String getString();
}
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package study.itest;

public class Two implements IOne {

 @Override
 public String getString() {
  return this.getClass().getName();
 }

}
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package study.itest;

public class Three implements IOne {

 @Override
 public String getString() {
  return this.getClass().getName();
 }

}
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package study.itest;

public class Output {

 public static void Show(IOne one) {
  System.out.println("Show:" + one.getString());
 }

 public static void main(String[] args) {
  IOne one = null;
  one = new Two();
  Show(one);
  one = new Three();
  Show(one);
 }
}