Why dont we get a compilation error for converting a collection into array?

Question

Why don't we get a compilation error but get a runtime error while explicit casting of Object[] into a String[]?
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
public class SampleMap {
  public static void main(String[] args) {
    Map<Integer, String> temp = new HashMap<Integer, String>();
    temp.put(new Integer(1), "cat");
    temp.put(new Integer(2), "rat");
    Collection coll = temp.values();
    String[] arr = (String[]) coll.toArray();
    System.out.println(arr.length);
} Thanks,
Harish Srinivasan

Answer 1

Infiniti wrote:
Why don't we get a compilation error but get a runtime error while explicit casting of Object[] into a String[]?
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
public class SampleMap {
public static void main(String[] args) {
Map<Integer, String> temp = new HashMap<Integer, String>();
temp.put(new Integer(1), "cat");
temp.put(new Integer(2), "rat");
Collection coll = temp.values();
String[] arr = (String[]) coll.toArray();
System.out.println(arr.length);
} Thanks,
Harish SrinivasanAn explicit cast's job is to tell the compiler that even though it cannot guarantee that the conversion will work, allow the code anyway and let the runtime handle an error if it occurs.