Java中的循环

import java.util.ArrayList;
import java.util.Iterator;


public class Practice {

public static void main(String[] args) {
int[] ary=new int [6];
ary[0] = 3;
ary[1] = 4;
ary[2] = 5;
ary[3] = 6;
ary[4] = 7;
ary[5] = 8;

int i=0;
while (i<ary.length) {
System.out.print(ary[i]);
i++;
}

System.out.println();

i=0;
do {
System.out.print(ary[i]);
i++;
} while (i<ary.length);

System.out.println();

for (i = 0; i < ary.length; i++) {
System.out.print(ary[i]);
}
System.out.println();

for (int j : ary) {
System.out.print(j);
}
System.out.println();

ArrayList<Integer> arr = new ArrayList<Integer>();
arr.add(new Integer(1));
arr.add(new Integer(2));
arr.add(new Integer(3));
arr.add(new Integer(4));

for (int k = 0; k < arr.size(); k++) {
System.out.print(arr.get(k)+" ");
}
System.out.println();

Iterator<Integer> iter= arr.iterator();//使用迭代器
while (iter.hasNext()) {
System.out.print(iter.next()+" ");
}

System.out.println();

for (Integer in : arr) {//使用增强的for循环--foreach，完全的迭代最简单
System.out.print(in + " ");
}
}
}