Java错误： <identifier> 预期在受保护的接口内部

Question

I am facing the following problem. I was trying to put together a simple tutorial on the strategy in Java when I ran into a problem. The compiler gives me an "<identifier> expected" error on the void do(int i); in the interface: Here is the full class:

import java.util.*;
public class Data {
private List<Integer> ints;

  public Data( int[] a ) {
    ints = new LinkedList<>(); 
    for( int i : a ) ints.add( i );
 }

 protected static interface Strategy{
    void do(int i);
 }

 protected void loop( Strategy s ) {
        for( int i : ints ) {
            s.do( i );
        }
    }
 }

Why am I getting this error? Thank you very much in advance.

Answer 1

The method name do is a Java keyword (Section 3.9, JLS) and can't be a method name. Change your method name to something not a keyword.

protected static interface Strategy{
    void doAction(int i);
}