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ÔÚjavaÖУ¬¼ÙÉèÄãÓÐÒ»¸öuser ¶ÔÏóµÄlist£¬´Ëuser¶ÔÏó·â×°ÁËÓû§µÄid, first name, last name and age. È»ºóÄãÏëµ÷ÓÃÒ»¸öweb service(eg. UserService.deleteUsersByIds(List<Integer> userIds) ȥɾ³ýÊý¾Ý¿âÖÐÖ¸¶¨µÄÕâЩuser¡£ ÌýÆðÀ´Ëƺõ²»Ì«À§ÄÑ£¬²»ÊÇô? ÄãËùÐèÒªÖ»Êǽ« List<User> ת»¯³ÉList<Integer>¡£ ËùÓÐÄãÏÈдÏÂÏÂÃæµÄ´úÂë:
List<Integer> ids = new ArrayList<Integer>(users.size());
for (User user : users) {
ids.append(user.getId());
}
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List<String> names = new ArrayList<String>(users.size());
for (User user : users) {
names.append(new StringBuilder(user.getFirstNam()).append(" ").append("user.getLastName()));
}
»òÐíÄ㻹ÐèÒªÒ»¸ö21ËêÒÔϵÄuser list¡£
List<User> newUsers= new ArrayList<User>(users.size());
for (User user : users) {
if(user.getAge()<21){
newUsers.add(user);
}
}
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<fromType, ToType> List<ToType> map(ArrayList<fromType> list) {
List<ToType> retval = new ArrayList<ToType>(list.size());
for (fromType item : list) {
[...]
}
return retval;
}
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1 List<Integer> ids = new ArrayList<Integer>(users.size());
2
for (User user : users) {
3
ids.append(user.getId());
4
}
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//header.jsp
out.println("Protocol: " + request.getProtocol() + "<br>");
out.println("Scheme: " + request.getScheme() + "<br>");
out.println("Server Name: " + request.getServerName() + "<br>" );
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* @Title: ${file_name}
* @Package ${package_name}
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NioSocketAcceptor acceptor = new NioSocketAcceptor(/*NioProcessorPool's size*/);
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public static boolean isNumeric(String str) {
for (int i = str.length(); i = 0;) {
if (!Character.isDigit(str.charAt(i))) {
return false;
}
}
return true;
}
public static boolean isNumeric(String str) {
Pattern patt ......