程序 4-4
import java.util.*;
public class MyVector extends Vector{
public MyVector(){
super(1,1); // 指定 capacity 和 capacityIncrement 取值
}
public void addInt(int i){
addElement(new Integer(i));
}
public void addFloat(float f){
addElement(new Float(f));
}
public void addString(String s){
addElement(s);
}
public void addCharArray(char a[]){
addElement(a);
}
public void printVector(){
Object o;
int length = size(); // 同capacity相比较
System.out.println("Number of vector elements is "+length+" and they are:");
for (int i = 0; i < length; i++){
o = elementAt(i);
if (o instanceof char[]){
//System.out.println(o); 不好
System.out.println(String.copyValueOf((char[]) o));
}
else
System.out.println(o.toString());
}
}
public static void main (String args[]){
MyVector v = new MyVector();
int digit = 5;
float real = 3.14f;
char letters[] = {'a','b','c','d'};
String s = new String ("Hi there!");

v.addInt(digit);
v.addFloat(real);
v.addString(s);
v.addCharArray(letters);
v.printVector();
}
}