java只有值传递！

/**
 * @author 031202
 *
 * TODO To change the template for this generated type comment go to Window -
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 */
class ValHold {
 public int i = 10;
}

public class TestParameter {
 public void amethod() {
  ValHold v = new ValHold();
  another(v);
  System.out.println(v.i);
 }

 public void another(ValHold v) {
  v.i = 20;
  ValHold vh = new ValHold();
  v = vh;
  System.out.println(v.i);
 }

 public static void main(String[] argv) {
  TestParameter o = new TestParameter();
  o.amethod();
 }
}

answer：
10
20