Some tricks of the servlet & template code

Some tricks of the servlet & template code

Request related

Get some basic parameters view source print?

01	Get Submit Address

02	Request.getrequesturi ();

03	Get Submit Content

04	Request.getquerystring ();

05	Get client address (browser)

06	Request.getremoteaddr ();

07	Get client port (browser)

08	Request.getremoteport ();

09	Get the Commit method (Get,post or ..... ）

10	Request.getmethod ();

Get Submit Content Body View Source print?

01	Get a Submit content parameter

02	Http://xxx/xx?username=flx

03	String username = request.getparameter ("username");

04	SYSTEM.OUT.PRINTLN (username);

05

06

07	Get some submit content parameters with the same name

08	Http://xxx/xx?username=flx&username=lhm

09	String values[] = request.getparametervalues ("username");

10	for (int i=0;values!=null && i<values.length;i++) {

11	System.out.println (Values[i]);

12

}

13

14	Gets a collection of all the submit parameters (not appropriate with an argument with the same name)

15	Enumeration E = Request.getparameternames ();

16	while (E.hasmoreelements ()) {

17	String name = (string) e.nextelement ();

18	String value = request.getparameter (name);

19	SYSTEM.OUT.PRINTLN (name + "=" + value);

20

}

21st

22	Get all parameter collections, suitable for parameters with the same name

23	Http://xxx/xx?username=flx&password=123

24	map<string,string[]> map = Request.getparametermap ();

25	Map.keyset () Set set = Map.entryset ()

26	For (map.entry<string, string[]> entry:map.entrySet ()) {

27	String name = Entry.getkey ();

28	Values = Entry.getvalue ();

29	for (String value:values) {

30	SYSTEM.OUT.PRINTLN (name + "=" + value);

31

}

32

}

Garbled Question View source print?

1	The content obtained by default is "Iso8859-1" encoding

2	String username = request.getparameter ("username");

3	First gets the original byte in the current encoding and then turns to the target encoding

4	Username = new String (username.getbytes ("iso8859-1"), "UTF-8");

5

6	You can also set the encoding manually

7	Request.setcharacterencoding ("UTF-8");

8	String username = request.getparameter ("username");

Use Org.apache.commons.beanutils to quickly populate the Bean view source print?

01	Get the submitted data collection

02	Map map = Request.getparametermap ();

03	This is a bean that stores the submitted data

04	User user = new user ();

05

06	Org.apache.commons.beanutils

07	A conversion tool for Beanutils, where a conversion of a date type is registered

08	Convertutils.register (New Converter () {//converter interface

09	Implementing this method, Convertutils knows how to convert the date type

10	public object Convert (Class type, Object value) {

11	Decide whether to be empty first

12	if (Value==null | | value.equals ("")) {

13	return null;

14

}

15	Determines whether a string

16	if (!) ( Value instanceof String)) {

17	throw new Conversionexception ("only string-type conversions are supported. ");

18

}

19	string s = (string) value;

20	Format a date string as a date type

21st	SimpleDateFormat SDF = new SimpleDateFormat ("Yyyy-mm-dd");

22

try {

23	return Sdf.parse (s);

24	catch (ParseException e) {

25	throw new Conversionexception (S + "is not a valid date value");

26

}

27

}

28	}, Date.class);

29

30	Start populating the collection into the bean map

31	Beanutils.populate (user, map);

Response related

Set browser cache view Source print?

01	Response the parameters in the body to describe the cache settings

02	Response.setheader ("Content-type", "image/jpeg");

03	Expires:-1

04	Cache-control:no-cache

05	Pragma:no-cache

06

07	Setting the browser does not cache data

08	Response.setdateheader ("Expires",-1);

09	Response.setheader ("Cache-control", "No-cache");

10	Response.setheader ("Pragma", "No-cache");

Output text view source print?

1	Set all methods of encoding format