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  . ³£¼ûµÄÊý×é´íÎóΪ : ArrayIndexOutOfBoundsException  (Êý×éÔ½½ç´íÎó)
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  . Ò»¸öÍⲿÀàÖ»ÔÊÐíÉùÃ÷Ϊpublic, abstact , final.
  . System.out.print ÊÇstatic·½·¨, ²»ÐèÒªnew´´½¨.
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  . Static  : ¿ÉÒÔÓ¦ÓÃÓÚÄÚ²¿Àà,·½·¨, ±äÁ¿.
                 ±êÖ¾Ò»¸ö±äÁ¿Îªstatic, ±íʾÆäÖ»ÄÜÓÐÒ»¸ö¸±±¾´æÔÚ.
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java Map ±éÀú·½·¨

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Map map = new HashMap();
Iterator iter = map.entrySet().iterator();
while (iter.hasNext()) {
Map.Entry entry = (Map.Entry) iter.next();
Object key = entry.getKey();
Object val = entry.getValue();
}
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Map map = new HashMap();
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public class Test {
public static void main(String[] args) {
for (int i = 0; i < args.length; i++) {
System.out.println(args[i].length() + ":" + args[i]);
}
}
}

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public static boolean validatePersonalId(String personalId) {

if ((personalId == null) || ((personalId.length() != 15) &&
(personalId.length() != 18))) {
return ......
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