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@lukhnos
Created September 9, 2015 14:56
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A case where you can't fast-enumerate an Iterable, 2/3
// Solution 1: Use annotation.
import com.google.j2objc.annotations.LoopTranslation;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
public class FastEnumGotcha {
static class Wrapper<T> {
T value;
void set(T value) {
this.value = value;
}
T get() {
return value;
}
}
static class Data implements Iterable<Wrapper<String>> {
List<String> strings;
Data(String[] strings) {
this.strings = Arrays.asList(strings);
}
@Override
public Iterator<Wrapper<String>> iterator() {
return new Iterator<Wrapper<String>>() {
Wrapper<String> w = new Wrapper<>();
Iterator<String> it = strings.iterator();
@Override
public boolean hasNext() {
return it.hasNext();
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
@Override
public Wrapper<String> next() {
w.set(it.next());
return w;
}
};
}
}
public static void main(String args[]) {
String x[] = {
"alpha", "bravo", "charlie", "delta", "echo", "foxtrot", "golf", "hotel", "india",
"juliet", "kilo", "lima", "mike", "november", "oscar", "papa", "quebec", "romeo",
"sierra", "tango", "uniform", "victor", "whiskey", "x-ray", "yankee", "zulu"
};
Data data = new Data(x);
for (@LoopTranslation(LoopTranslation.LoopStyle.JAVA_ITERATOR) Wrapper<String> w : data) {
System.out.printf("%s ", w.get());
}
System.out.println();
}
}
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