Head First Servlets and JSP phần 5 ppt

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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
XVLQJ-63
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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9OUCANDOSERVLETINITIALIZATIONSTUFFINYOUR*30BUTITSSLIGHTLY
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METHODATTHEBEGINNINGOFTHISPAGESLIFEASASERVLET)TSCALLEDFROMTHESERVLETS
INITMETHODSOBYTHETIMETHISMETHODRUNSTHEREISA3ERVLET#ONlGAND
3ERVLET#ONTEXTAVAILABLETOTHESERVLET4HATMEANSYOUCANCALLGET3ERVLET#ONlG
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CONlGUREDINTHE$$ANDUSESTHEVALUETOSETANAPPLICATIONSCOPEDATTRIBUTE
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YouÕre in a servlet, so you
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getServletConÞg() method!
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9OUCONlGURESERVLETINITPARAMSFORYOUR*30VIRTUALLYTHESAMEWAYYOU
CONlGURETHEMFORANORMALSERVLET4HEONLYDIFFERENCEISTHATYOUHAVE
TOADDAJSPlLEELEMENTWITHINTHESERVLETTAG
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This is EXACTLY what
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and set an application-scope attribute.
This is the only line thatÕs different from
a regular servlet. It basically says, Òapply
everything in this <servlet> tag to the
servlet created from this JSP page Ó
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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TIMEYOULLBEUSINGONEOFTHEFOURIMPLICITOBJECTSTOGETANDSETATTRIBUTES
CORRESPONDINGTOTHEFOURATTRIBUTESCOPESAVAILABLEINA*30
9ESFOUR2EMEMBERINADDITIONTOTHESTANDARDSERVLETREQUESTSESSIONAND

APPLICATIONCONTEXTSCOPESA*30ADDSAFOURTHSCOPEPAGESCOPETHATYOUGET
FROMAPAGE#ONTEXTOBJECT
9OUUSUALLYWONTNEEDORCAREABOUTPAGESCOPEUNLESSYOUREDEVELOPING
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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CONSTANTSFORTHESCOPESINSIDETHE0AGE#ONTEXTCLASS
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
XVLQJ-63
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
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Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
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Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:

O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.

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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP

Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
XVLQJ-63
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
XVLQJ-63
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.
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Chapter 7. Being a JSP
Chapter 7. Being a JSP
Head First Servlets and JSP By Bert Bates, Kathy Sierra, Bryan Basham ISBN: 0596005407 Publisher:
O'Reilly
Prepared for Augusto Jaramillo Forcada, Safari ID:
Print Publication Date: 8/1/2004 User number: 729515 Copyright 2007, Safari Books Online, LLC.
This PDF is exclusively for your use in accordance with the Safari Terms of Service. No part of it may be reproduced or transmitted in any form by any means without the prior
written permission for reprints and excerpts from the publisher. Redistribution or other use that violates the fair use priviledge under U.S. copyright laws (see 17 USC107) or that
otherwise violates the Safari Terms of Service is strictly prohibited.