jdk5: for循环(for loop) 提供了同迭代器(iterator)一起使用的更简洁和更少出错的for循环版本。增强循环(Enhanced for Loop) 旧的循环LinkedList list = new LinkedList(); list.add("Hi"); list.add("everyone!"); list.add("Was"); list.add("the"); list.add("pizza"); list.add("good?"); for (int i = 0; i < list.size(); i++) System.out.println((String) list.get(i)); //或者用以下循环 //for(Iterator iter = list.iterator(); iter.hasNext(); ) { //Integer stringObject = (String)iter.next(); // ... more statements to use stringObject... //} 新的循环LinkedList<String> list = new LinkedList<String>(); list.add("Hi"); list.add("everyone!"); list.add("Was"); list.add("the"); list.add("pizza"); list.add("good?"); for (String s : list) System.out.println(s);
for(int i:ints)
System.out.println(i);
}
public class TFor {
public static void main(String args[]) {
int ints[] = {5,4,3,2,1} ;
for(int i:ints) {
System.out.println(i) ;
}
}
}
java 5.0有这样的语法的
foreach(int i in ints)
其实意思就是在ints中循环取出值并赋给i
int[] nums = {1,2,3,4}
for(int num : nums) {
System.out.println(num);
}List<String> list = new ArrayList<String>();
lists.add("1");
lists.add("2");
lists.add("3");
for(String str : list) {
System.out.println(str);
}Map<String, String> map = new LinkedHashMap<String, String>();
map.put("a", "1");
map.put("b", "2");
map.put("c", "3");
for(Map.Entry<String, String> entry : map.entrySet()) {
System.out.println(entry.getKey() + " --> " + entry.getValue());
}
for循环(for loop) 提供了同迭代器(iterator)一起使用的更简洁和更少出错的for循环版本。增强循环(Enhanced for Loop) 旧的循环LinkedList list = new LinkedList(); list.add("Hi");
list.add("everyone!");
list.add("Was");
list.add("the");
list.add("pizza");
list.add("good?");
for (int i = 0; i < list.size(); i++)
System.out.println((String) list.get(i));
//或者用以下循环
//for(Iterator iter = list.iterator(); iter.hasNext(); ) {
//Integer stringObject = (String)iter.next();
// ... more statements to use stringObject...
//} 新的循环LinkedList<String> list = new LinkedList<String>(); list.add("Hi");
list.add("everyone!");
list.add("Was");
list.add("the");
list.add("pizza");
list.add("good?");
for (String s : list)
System.out.println(s);