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import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class SafeListCopy extends Object {
public static void printWords(String[] word) {
System.out.println("word.length=" + word.length);
for (int i = 0; i < word.length; i++) {
System.out.println("word[" + i + "]=" + word[i]);
}
}
public static void main(String[] args) {
List wordList = Collections.synchronizedList(new ArrayList());
wordList.add("Synchronization");
wordList.add("is");
wordList.add("important");
String[] wordA = (String[]) wordList.toArray(new String[0]);
printWords(wordA);
String[] wordB;
synchronized (wordList) {
int size = wordList.size();
wordB = new String[size];
wordList.toArray(wordB);
}
printWords(wordB);
// Third technique (the 'synchronized' *is* necessary)
String[] wordC;
synchronized (wordList) {
wordC = (String[]) wordList.toArray(new String[wordList.size()]);
}
printWords(wordC);
}
}
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