Create array with Array.newInstance

转自http://www.java2s.com/Tutorial/Java/0125__Reflection/CreatearraywithArraynewInstance.htm

import static java.lang.System.out;

import java.lang.reflect.Array;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.util.Arrays;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class ArrayCreator {
  private static String s = "int bi[] = { 123, 234, 345 }";
  private static Pattern p = Pattern
      .compile("^\\s*(\\S+)\\s*\\w+\\[\\].*\\{\\s*([^}]+)\\s*\\}");

  public static void main(String... args) {
    Matcher m = p.matcher(s);

    if (m.find()) {
      String cName = m.group(1);
      String[] cVals = m.group(2).split("[\\s,]+");
      int n = cVals.length;

      try {
        Class<?> c = Class.forName(cName);
        Object o = Array.newInstance(c, n);
        for (int i = 0; i < n; i++) {
          String v = cVals[i];
          Constructor ctor = c.getConstructor(String.class);
          Object val = ctor.newInstance(v);
          Array.set(o, i, val);
        }

        Object[] oo = (Object[]) o;
        out.format("%s[] = %s%n", cName, Arrays.toString(oo));

        // production code should handle these exceptions more gracefully
      } catch (ClassNotFoundException x) {
        x.printStackTrace();
      } catch (NoSuchMethodException x) {
        x.printStackTrace();
      } catch (IllegalAccessException x) {
        x.printStackTrace();
      } catch (InstantiationException x) {
        x.printStackTrace();
      } catch (InvocationTargetException x) {
        x.printStackTrace();
      }
    }
  }
}