Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 S~hNSw(-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ~)ls.NXI
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 B+ +:7!
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 /_v@YB!0
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分页支持类: kP3'BBd,
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java代码: lj(}{O
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package com.javaeye.common.util; "YM)bc
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import java.util.List; 49cQA$Ad
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publicclass PaginationSupport { ~]3y667
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publicfinalstaticint PAGESIZE = 30; %R(1^lFI$
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privateint pageSize = PAGESIZE; r!'\$(m E
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privateList items; 1t6VS 3
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privateint totalCount; mJp)nF8r~
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privateint[] indexes = newint[0]; -:&qNY:Vp
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privateint startIndex = 0; W&qE_r
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public PaginationSupport(List items, int 8V?O=3<a
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totalCount){ B/7c`V
setPageSize(PAGESIZE); P
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setTotalCount(totalCount); va[@XGaC3
setItems(items); `L /\F,
setStartIndex(0); NLf6}
} LNPwb1)
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public PaginationSupport(List items, int sz9C':`W
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totalCount, int startIndex){ _Gvn1"l
setPageSize(PAGESIZE); |5^tp
setTotalCount(totalCount); e4ym6q<6!
setItems(items); kO>F, M
setStartIndex(startIndex); .IXkdy
} |]y]K%
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public PaginationSupport(List items, int BxVo>r
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totalCount, int pageSize, int startIndex){ b S[;d5
setPageSize(pageSize); p'tB4V qT
setTotalCount(totalCount); 5ELKL#(
setItems(items); Zl^#U c"
setStartIndex(startIndex); }&M$
} +zn&DG0\X
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publicList getItems(){ Z:j6AF3;
return items; b=(?\
} QpbyC_:;$4
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publicvoid setItems(List items){ ?B7n,!&~
this.items = items; 9x$Kb7'F
} uY{V^c#mv
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publicint getPageSize(){ J0K25w
return pageSize; v0v%+F#>@
} 8&+m5xS
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publicvoid setPageSize(int pageSize){ %iMRJ}8(7
this.pageSize = pageSize; jzt$
} aAJ'0xnj
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publicint getTotalCount(){ WCJ$S\#
return totalCount; QU{|S.\
} b5NPG N
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publicvoid setTotalCount(int totalCount){ IWc?E
if(totalCount > 0){ "-bsWC
this.totalCount = totalCount; 4AA3D!$
int count = totalCount / KVQ|l,E,
/
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pageSize; <Wqk5mR
if(totalCount % pageSize > 0) bLSXQStB
count++; N{rC#A3
indexes = newint[count]; 8Evon&G59
for(int i = 0; i < count; i++){ 4K{<R!2I
indexes = pageSize * 1HPYW7jk@"
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i; St 4YNS.|
} O{@m ,uY
}else{ >AFX}N#
this.totalCount = 0; :56f
} Ut|G.%1Vd%
} -SO`wL NV
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publicint[] getIndexes(){ k?[|8H~2C
return indexes; "eRf3Q7w:
} *|97 g*G(
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publicvoid setIndexes(int[] indexes){ J)yNp,V
this.indexes = indexes; ii,/omn:
} (?[^##03MN
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publicint getStartIndex(){ -`knSR
return startIndex; `GGACH3# s
} x|3f$
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publicvoid setStartIndex(int startIndex){ #RIo63
if(totalCount <= 0) n\CQ-*;l
this.startIndex = 0; 6<E4?<O%
elseif(startIndex >= totalCount) 2pu8')'P
this.startIndex = indexes g3*" ^C2=
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[indexes.length - 1]; BC}+yS
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elseif(startIndex < 0) oz54IO
this.startIndex = 0; 8}5dyn{cvE
else{ ciQG.]
this.startIndex = indexes "j(?fVx
r0 mXRZC
[startIndex / pageSize]; <]9%Pm#X
} =~7%R.U([e
} [ vWcQ6m
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publicint getNextIndex(){ _DlkTi5(w
int nextIndex = getStartIndex() + 4|PNsHXt
\*24NB
pageSize; 1lAx"VL
if(nextIndex >= totalCount) "'M>%m u
return getStartIndex(); /d<"{\o
else 8`edskWrU
return nextIndex; " w0[l"3V
} DH@})TN*O
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publicint getPreviousIndex(){ 8V]oR3'
int previousIndex = getStartIndex() - ?$:;hGO.<~
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pageSize; EKwA1,Xz
if(previousIndex < 0) x^s2bb
return0; Cq-d,
else -5v2E-
return previousIndex; HW0EP J
} Ai99:J2k
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} HC'k81Q
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抽象业务类 +}MV$X
java代码: auzrM4<tz
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/** ,<,ige
* Created on 2005-7-12 fevLu[,
*/ oN0p$/La
package com.javaeye.common.business; z%
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import java.io.Serializable; v&.`^O3W
import java.util.List; >O7ITy
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import org.hibernate.Criteria; 8A|{jH74
import org.hibernate.HibernateException; 0)c9X[sG
import org.hibernate.Session; C&d%S|:IR
import org.hibernate.criterion.DetachedCriteria; \dIc_6/D1
import org.hibernate.criterion.Projections; !>%U8A
import OI=LuWGQE1
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org.springframework.orm.hibernate3.HibernateCallback; ZjlFr(
import cy0
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\ow3_^Bk
org.springframework.orm.hibernate3.support.HibernateDaoS u9d4zR
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upport; T);eYC"@
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import com.javaeye.common.util.PaginationSupport; V !Cu%4
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public abstract class AbstractManager extends pP1|/f5n`
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HibernateDaoSupport { .I6:iB
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privateboolean cacheQueries = false; Nk~Xz
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privateString queryCacheRegion; ]e*Zx;6oi
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publicvoid setCacheQueries(boolean u!&w"t61Nd
[# X:!xcl
cacheQueries){ ,&wTUS\
this.cacheQueries = cacheQueries; D][e uB
} %SWtE5HZQq
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publicvoid setQueryCacheRegion(String y;0k |C
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queryCacheRegion){ aWp9K+4R$/
this.queryCacheRegion = 4v@urW s
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queryCacheRegion; 50 s)5G#
} ^H0`UKE
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publicvoid save(finalObject entity){ ^uU'Qc4S=
getHibernateTemplate().save(entity); 9t`Z_HwdCb
} MhE'_sq
8 *Fr=+KN
publicvoid persist(finalObject entity){ @,b:s+]rp
getHibernateTemplate().save(entity); b zz{ p1e
} ^8_`IT
) h*)_7
publicvoid update(finalObject entity){ (6 jr}kP
getHibernateTemplate().update(entity); auV'`PR
} Kp_L\'.I5$
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publicvoid delete(finalObject entity){ ~2R3MF.C
getHibernateTemplate().delete(entity); %]>LnbM>4
} @iC,0AK4k
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publicObject load(finalClass entity, HA
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finalSerializable id){ os\"(*dix
return getHibernateTemplate().load c0lVt)pr/
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(entity, id); ^bVY&iXNu
} _}_lrg}U
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publicObject get(finalClass entity, 1wx&/#a
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finalSerializable id){ h6!o,qw"
return getHibernateTemplate().get ya+eGD@N':
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(entity, id); 'IaI7on
} /}~;
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publicList findAll(finalClass entity){ /ae]v+
return getHibernateTemplate().find("from ELx?ph -9
m?Gb5=qo
" + entity.getName()); !&~8j7{
} ?V6+o`bm
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publicList findByNamedQuery(finalString DYvi1X6
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namedQuery){ Jm%hb,
return getHibernateTemplate ^1&xt(G
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().findByNamedQuery(namedQuery); fk(l.A$
} OG#7Va
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publicList findByNamedQuery(finalString query, 3@k;"pFa<
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finalObject parameter){ 91oIx W
return getHibernateTemplate V^qZ~US
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().findByNamedQuery(query, parameter); F8q &v"
} O*af`J{
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publicList findByNamedQuery(finalString query, ]jWe']T
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finalObject[] parameters){ OL{U^uOhY
return getHibernateTemplate m6qmZ2<
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().findByNamedQuery(query, parameters); gnS0$kCJ:
} &} b'cO
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publicList find(finalString query){ %ZV a{Nc
return getHibernateTemplate().find kcH?l
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(query); >\Qyg>Md]
} WMB~?
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publicList find(finalString query, finalObject w%,Iy,G@
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parameter){ (7nWv43
return getHibernateTemplate().find & A=q _
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(query, parameter); ~%Y*2i
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} _7SOl.5ZE
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public PaginationSupport findPageByCriteria RRaGc )B
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(final DetachedCriteria detachedCriteria){ JGaS`fKSk
return findPageByCriteria Sr_]R<?
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *Z7W'-
} &~
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public PaginationSupport findPageByCriteria saOXbt(&
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(final DetachedCriteria detachedCriteria, finalint @] .Ko[P~
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startIndex){ W
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return findPageByCriteria I;`)1
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(detachedCriteria, PaginationSupport.PAGESIZE, E<>Ev_5 >
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startIndex); #UH|,>W6
} Q!Rknj 2
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public PaginationSupport findPageByCriteria V0mWY!i
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(final DetachedCriteria detachedCriteria, finalint |F36^
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pageSize, 4#mRLs'
finalint startIndex){ MD ~03
return(PaginationSupport) gIS<"smOo
}q-_|(b;
getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate EfY|S3Av
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(Session session)throws HibernateException { <`EZ^S L;
Criteria criteria = %&bO+$H3
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detachedCriteria.getExecutableCriteria(session); &1:xY.Zs_
int totalCount = :)+|q
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((Integer) criteria.setProjection(Projections.rowCount CuPZ0
9;u$a^R.
()).uniqueResult()).intValue(); )*N]Q
criteria.setProjection oB8u[!
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(null); |`9POl=
List items = =LHE_ AA
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criteria.setFirstResult(startIndex).setMaxResults sHO6y0P
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(pageSize).list(); nG&=$7x^
PaginationSupport ps = ;5 cg<~t
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new PaginationSupport(items, totalCount, pageSize, c@)k#/[[b
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startIndex); MWGW[V;
return ps; Q9)/INh
} U3MfEM!x
}, true); :(,uaX>{
} ny17(Y =
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public List findAllByCriteria(final g"|QI=&_J
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DetachedCriteria detachedCriteria){ Kx?3 ]
return(List) getHibernateTemplate WE\912j
Px&*&^Gf[b
().execute(new HibernateCallback(){ [Y.3miE
publicObject doInHibernate [gFpFz|b<
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(Session session)throws HibernateException { -Cv:lJj
Criteria criteria = g*Nc+W](P>
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detachedCriteria.getExecutableCriteria(session); cYyv
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return criteria.list(); aS?A3h4WM_
} +`l>_u'
}, true); )r-t$ L
} #(-V^T
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public int getCountByCriteria(final xlF$PpRNM
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DetachedCriteria detachedCriteria){ Iz^~=yV)
Integer count = (Integer) E$m3Gg)s>N
#\1;d8h
getHibernateTemplate().execute(new HibernateCallback(){ "NSm2RU3
publicObject doInHibernate TYW$=p|
ext`%$ U7
(Session session)throws HibernateException { ;
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Criteria criteria = .r+ u pY
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detachedCriteria.getExecutableCriteria(session); Epsc2TuH7
return \D>vdn"Lx
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criteria.setProjection(Projections.rowCount ^Fgmwa'
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()).uniqueResult(); D
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} =Y>_b
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}, true); ['j_W$8n
return count.intValue(); 61>@-55k9
} si,fs%D&
} 3{ i'8
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{\
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用户在web层构造查询条件detachedCriteria,和可选的 ^yg`U(
i>i@r ;:|
startIndex,调用业务bean的相应findByCriteria方法,返回一个 'S\YNLqQ
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PaginationSupport的实例ps。 :VC#\/f
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ps.getItems()得到已分页好的结果集 &yN@(P)
ps.getIndexes()得到分页索引的数组 VnW]-P*:
ps.getTotalCount()得到总结果数 % \Nfj)9
ps.getStartIndex()当前分页索引 2,?4'0Z@R
ps.getNextIndex()下一页索引 L}lOA,EF
ps.getPreviousIndex()上一页索引 74hGkf^S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 x0B|CO
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 @SeE,<
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一下代码重构了。 o^%4w>|
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我把原本我的做法也提供出来供大家讨论吧: 0\#uxzdhJ
DZKVZ_q
首先,为了实现分页查询,我封装了一个Page类: i&\N_PUm[
java代码: 5fuOl-M0W
DJP)V8]!B
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/*Created on 2005-4-14*/
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package org.flyware.util.page; YqwDvJWX
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/** .w2X24Mmb
* @author Joa _!6~o>
* OnFx8r:q@%
*/ AHX_I
publicclass Page { 4HEp}Y"}V
VE1 B"s</
/** imply if the page has previous page */ RGh`=D/yE
privateboolean hasPrePage; jrT5Rw_}q
GY 4?}T^s
/** imply if the page has next page */ MB;<F
privateboolean hasNextPage; m~ :W$x1+
tep_g4CQR_
/** the number of every page */ &>43l+
privateint everyPage; Ex^|[iV
6U)Lhf\'o
/** the total page number */ "MZj}}l
privateint totalPage; ;Q>(%"z};
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/** the number of current page */ !~PLW] Z4
privateint currentPage; 1^rODfY 0
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/** the begin index of the records by the current pv1J6
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query */ u! `oKe;
privateint beginIndex; %cJ]Ds%V
@q2If{Tk
m@ b~
/** The default constructor */ EdxTaR
public Page(){ zS*GYE(l^
(wLzkV/6
} d4<Ic#
yE L^Y'x?
/** construct the page by everyPage q5J6d+
* @param everyPage OO5k_J
* */ @*jd.a`
public Page(int everyPage){ 7RNf)nz
this.everyPage = everyPage; i9fK`:)
} %toxZ}OP
"Wd?U[[
/** The whole constructor */ C'3/B)u}l
public Page(boolean hasPrePage, boolean hasNextPage, tAH,3Sz( /
j&) "a,f
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int everyPage, int totalPage, 6-C9[[g<
int currentPage, int beginIndex){ 0]3%BgZ(a8
this.hasPrePage = hasPrePage; Hp;Dp!PLa
this.hasNextPage = hasNextPage; JK0L&t<
this.everyPage = everyPage; i~
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this.totalPage = totalPage; @(2DfrC
this.currentPage = currentPage; fwB+f`w`
this.beginIndex = beginIndex; 13(JW
} >i=^Mh-bm
oyV@BHJO@
/** xgP/BK2"
* @return 44axOk!G[/
* Returns the beginIndex. 7Wub@Mp
*/ 6(
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publicint getBeginIndex(){ <*u[<
return beginIndex; &scHyt
} Qk?;n F
#7K&x.w$
/** !Tuc#yFw
* @param beginIndex gf2<dEff
* The beginIndex to set. ZVu&q{s,
*/ Mo`7YS-Y
publicvoid setBeginIndex(int beginIndex){ * Zb-YA
this.beginIndex = beginIndex; [|<2BQX
} RGy4p)z*+
}|>mR];
/** l?E7'OEF:
* @return (.Yt|
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* Returns the currentPage. Dn;6O
*/ 8;>vgD
publicint getCurrentPage(){ Fa78yY+6
return currentPage; #MYhKySku
} T1yJp$yD"
Z!o&};_j
/** \9*wo9cV
* @param currentPage \A'MEd-
* The currentPage to set. `Cy-*$$
*/ yAOYe"d
publicvoid setCurrentPage(int currentPage){ @Q~Oc_z
this.currentPage = currentPage; b}63?.M{
} xJ H]>#XJ
><9E^ k0.
/** c0M=T
* @return afY~Y?PJ<
* Returns the everyPage. sE7!U|
*/ L ;5uB2
publicint getEveryPage(){ R /J@XP
return everyPage; F.ml]k&(m
} n]G!@-z
=w='qjh
/** h; 105$E1
* @param everyPage bp Q/#\Z
* The everyPage to set. V~p/P
*/ ZnDI
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publicvoid setEveryPage(int everyPage){ hhQLld4
this.everyPage = everyPage; Sgp$B:
} lN"%~n?
)z#
/** qTFktJZw
* @return 3>%oGbo
* Returns the hasNextPage. 4kZX$ct}
*/ Z^w11}
publicboolean getHasNextPage(){ m~a'
return hasNextPage; g2;!AI5f
} #`R`!4
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/** ~_^#/BnAl
* @param hasNextPage k fS44NV
* The hasNextPage to set. 0 =#)-n
*/ h6c0BmS{1
publicvoid setHasNextPage(boolean hasNextPage){ t3%[C;@wB
this.hasNextPage = hasNextPage; lJHV c"*/
} ^b)8l
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/** Cisv**9
* @return $oKT-G
* Returns the hasPrePage. b
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*/ 2t'^
publicboolean getHasPrePage(){ ;`<uo$R
return hasPrePage; ir^%9amh
} g_8Bhe"ik
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/** []R`h*#
* @param hasPrePage Yg_;Eu0'?
* The hasPrePage to set. tNf?pV77
*/ P9(]9np,,
publicvoid setHasPrePage(boolean hasPrePage){ L|hsGm\
this.hasPrePage = hasPrePage; c\.Hs9T >
} T;/Y/Fd
?`R;ZT)U-
/** ZZ/F}9!=
* @return Returns the totalPage. <n+?7`d,
* )Zx;Z[
*/ #P[d?pY
publicint getTotalPage(){ oJ}!qrrH
return totalPage; ~"-+BG(5
} >
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os/_ObPiX
/** O3,IR1
* @param totalPage yu8xTh$:
* The totalPage to set. k@QU<cvI
*/ V2-fJ!
publicvoid setTotalPage(int totalPage){ _?]E)i'RI
this.totalPage = totalPage; w7d(|`
} CMk0(sztU_
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'K
} -58
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g *}M;"
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Imi;EHW
|#hj O3
个PageUtil,负责对Page对象进行构造: GF(<!PC
java代码: @lvvI<U
Z!\xVCG"q
8}9B*m
/*Created on 2005-4-14*/ &fH;A X.
package org.flyware.util.page; tNsiokOm
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import org.apache.commons.logging.Log; vU5a`0mH
import org.apache.commons.logging.LogFactory; vFuf{ @P
Z)=S. )
/** ')!+>b(P
* @author Joa F$[1KjS
* 2flgfB}2k
*/ )3h%2C1uM
publicclass PageUtil { M'Fa[n*b?!
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privatestaticfinal Log logger = LogFactory.getLog A6D.bJ)
_^{!`*S
(PageUtil.class); p6=L}L
=3KK/[2M
/** .9r+LA{
* Use the origin page to create a new page ;IklS*p]
* @param page V5$J
* @param totalRecords <HReh>)[
* @return jSLC L'
*/ y*i_Ec\h
publicstatic Page createPage(Page page, int Ln~Z_!
GTvp)^h
totalRecords){ ]`[r=cG
return createPage(page.getEveryPage(), RZwjc<T
$:|z{p
page.getCurrentPage(), totalRecords); ldEZ _g^
} C?IvXPlV
8=XfwwWHy<
/** gWlv;oq
* the basic page utils not including exception NI(fJ%U
'FVh/};Y.D
handler ^.']-XjC
* @param everyPage :Bk!YK
* @param currentPage v.eN Wp
* @param totalRecords G-5wv
* @return page kVu8/*Q
*/ bwHl}3
publicstatic Page createPage(int everyPage, int G8Hj<3`
]
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currentPage, int totalRecords){ JPeZZ13sS
everyPage = getEveryPage(everyPage); \2$-.npz
currentPage = getCurrentPage(currentPage); h( lkC[a&
int beginIndex = getBeginIndex(everyPage, p8yn? ~]^
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currentPage); Dm=d
int totalPage = getTotalPage(everyPage, iF.eBL%
/]0-|Kg+R
totalRecords); 014p = W
boolean hasNextPage = hasNextPage(currentPage, qx#k()E.U
] qT\z<}
totalPage); N#C"@,}Y
boolean hasPrePage = hasPrePage(currentPage); eVRFb#EU0e
-K+" :kiS
returnnew Page(hasPrePage, hasNextPage, irqNnnMGEa
everyPage, totalPage, cQ:Y@f 9
currentPage, d[h2Y/AR
'A#`,^]uLF
beginIndex); -c%K_2`
} )9(Mt_
RPb/U8
privatestaticint getEveryPage(int everyPage){ Vfm (K
return everyPage == 0 ? 10 : everyPage; &``dI,NC
} fT7Z6$
sIx8,3`&y
privatestaticint getCurrentPage(int currentPage){ axf 4N@
return currentPage == 0 ? 1 : currentPage; /CpU.^V
} DA>_9o/l
L;wfTZa
privatestaticint getBeginIndex(int everyPage, int Mi|PhDXMh
>]6inS9
currentPage){ ;.%Ii
w&WG
return(currentPage - 1) * everyPage; 1J(` kQ)c
} MS`wd
#bFJ6;g=V
privatestaticint getTotalPage(int everyPage, int I/whpOg
<
5%:/j
totalRecords){ 43i@5F]
int totalPage = 0; g>])O
Vl91I+Ev
if(totalRecords % everyPage == 0) qu}`;\9@ld
totalPage = totalRecords / everyPage; ROWb:tX}
else _RzwE$+9
totalPage = totalRecords / everyPage + 1 ; $UgQ1Qc
2(_+PQ6C=
return totalPage; b<]--\
} ^|h5*Tb
XiP xg[;
privatestaticboolean hasPrePage(int currentPage){ ]h]| PdN
return currentPage == 1 ? false : true; -2)6QKh~D
} !/1aot^(
*'b3Z3c,;
privatestaticboolean hasNextPage(int currentPage, u`%Kh_
(A\X+S(
int totalPage){ 2WKYf0t
return currentPage == totalPage || totalPage == 0+a-l[!p
;<aT|4
0 ? false : true; Zd2B4~V
} );8Nj
zX1
OxGS{zs
_$wXHONt
} <=]wh|D
0nz=whS{
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,
HnDz4eD
i_ha^mq3
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ,\HZIl[8
J$9`[^pV
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 PS" ,
7~gIOu
做法如下: &rdz({
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v#. %eF
m
1qEpQ.:](
的信息,和一个结果集List: MfX1&/Z+
java代码: {8'f>YP
; O6Ez-"
X(sN+7DOV
/*Created on 2005-6-13*/ Ec44JD
package com.adt.bo; (\CT
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f)~j'e
import java.util.List; +[ +4h}?
QD<GXPu?N
import org.flyware.util.page.Page; `k ^d)9
Q]Kc<[E
/** TLBIM
* @author Joa J}$St|1y
*/ av}Giz
publicclass Result { In[!g
15o<'4|=Lm
private Page page; Gxtqzr*
v-(Ry<fT9
private List content; *bi!iz5F
*.4VO+^
/** Y|*a,H"_
* The default constructor OGDCC/
*/ <{t*yMr
public Result(){ K,ccM[hu|
super(); j_3X
1w)k
} mes/gqrJ1I
V30Om3C
/** w=dTa5
* The constructor using fields ,YEwz3$5u
* EWcqMD]4u
* @param page x]e&G!|
* @param content Bl\/q83(
*/ B)q 5m
y
public Result(Page page, List content){ Cb`2" mpWS
this.page = page; *B$$6'hi`
this.content = content; 91|0{1
} OA_WjTwDs
fFr[
&\[
/** ?h7,q*rxk
* @return Returns the content. vz\^Aa
#fv
*/ Ng1{NI+S
publicList getContent(){ SxAZ2|/-
return content; &d!Q%
} Hp#IOsP~
^HO'"/tB@D
/** qs9q{n-Aj
* @return Returns the page. T:~c{S4&
*/ |8DMj s()*
public Page getPage(){ G_5uO58
return page; ^lI>&I&1
} }K
rQPg
,Q7W))j
/** bu}N{cW
* @param content X(YR).a~
* The content to set. cft'% IEs
*/ >Y3ZK{b
public void setContent(List content){ =>y%Aj&4
this.content = content; ;5ANw"Dq
} vVA)x~^
:n%KHen3\
/** a 8(mU%
* @param page j9voeV|7
* The page to set. >EVY,
*/ pA~eGar_J
publicvoid setPage(Page page){ +\Zr\fOe|%
this.page = page; j\/Rjn+:[
} "DpgX8lG_
} D^\gU-8M
<w9<G
ZQ MK1
p+ki1!Ed
K6..N\7
2. 编写业务逻辑接口,并实现它(UserManager, @xqjAcfg
a7Xa3 vlpO
UserManagerImpl) h)~i?bq!/
java代码: H
N )@sLPc
eHIsTL@Fp
y}.?`/Q#
/*Created on 2005-7-15*/
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package com.adt.service; t,v=~LE
?'jRUf l
import net.sf.hibernate.HibernateException; s)eU^4m
UtpK"U$XOU
import org.flyware.util.page.Page; R9-Ps qmF
]:K[{3iM
import com.adt.bo.Result; ML)5nJD
x5Z(_hU
/** s|q]11r+H
* @author Joa -9X#+-
*/ uhf%
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publicinterface UserManager { RaX:&PE
1OwVb
public Result listUser(Page page)throws #P^cR_|\
~HM,@5dFC
HibernateException; ^! r<-J
Z~s"=kF,
} W "}Cfv
A4|L;z/A[h
H[;\[3
m})EYs1
DV6B_A{kI
java代码: kJfMTfl,
Jh6 z5xUV
p10i_<J]=
/*Created on 2005-7-15*/ ]Av)N6$&-Z
package com.adt.service.impl; C8oAl3d+h
=Felo8+
import java.util.List; iN]#XIQ%
b-Uy&+:X*d
import net.sf.hibernate.HibernateException; |s}7<A
:'+- %xUM
import org.flyware.util.page.Page; :#pfv)W6t
import org.flyware.util.page.PageUtil; aR@s.
ll
$!m (S&f
import com.adt.bo.Result; wpW3%r;9
import com.adt.dao.UserDAO; IMF9eS{L
import com.adt.exception.ObjectNotFoundException; 'xn3g ;5
import com.adt.service.UserManager; Q"Ur*/-U
s6F^z\6
/** O"c@x:i
* @author Joa ymr#OP$<S
*/ Xb'UsQ
publicclass UserManagerImpl implements UserManager { d8V)eZYXy~
zF-M9f$_PY
private UserDAO userDAO; FKVf_Ncf%
nUy2)CL[L
/** 0+P[0
* @param userDAO The userDAO to set. 4!,`|W1
*/ c
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publicvoid setUserDAO(UserDAO userDAO){ Ug=)_~
this.userDAO = userDAO; 6+Bccqn|
} \5ZDP3I
Ic,V,#my
/* (non-Javadoc) O>~ozW&
* @see com.adt.service.UserManager#listUser X1J'
|."thTO
(org.flyware.util.page.Page) u,f$cR
*/ 9-6E(D-ux
public Result listUser(Page page)throws -$0w-M8'
Z'ZN^j{
HibernateException, ObjectNotFoundException { KgCQ4w9
int totalRecords = userDAO.getUserCount(); oDvE0"Sz
if(totalRecords == 0) /OaW4 b$Tz
throw new ObjectNotFoundException #sg^l>/*
3R|C$+Sc
("userNotExist"); +. ` I
page = PageUtil.createPage(page, totalRecords); )8244;
List users = userDAO.getUserByPage(page); *^WY+DV
returnnew Result(page, users); 017(I:V?(:
} 7Ns1b(kU
_1sjsGp>
} B+w< 0No
b+DBz}L4
`N,q~@gL
1TIP23:
>qT4'1S*g
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查
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^7zXi xp
询,接下来编写UserDAO的代码: v?
VNWK2
3. UserDAO 和 UserDAOImpl: '*XX|\.
java代码: g,,'Pdd7Pn
{;0+N -U
? 016
/*Created on 2005-7-15*/ N %K%0o-
package com.adt.dao; s<;kTReA
MNzWTn@
import java.util.List; <dA D-2O+
q/N1q&
import org.flyware.util.page.Page; /A{/
6k%Lc4W
import net.sf.hibernate.HibernateException; ,f(:i^iz!
%=t8
/** 4#c-?mh_
* @author Joa WdvXVF
*/ (='e9H!3D
publicinterface UserDAO extends BaseDAO { ra[*E4P9L*
q8_8rp-@
publicList getUserByName(String name)throws <JyF5
d4]9oi{}
HibernateException; kTQvMa-X9D
|5h~&kA
publicint getUserCount()throws HibernateException; iXJ3B&x
Xu+^41
publicList getUserByPage(Page page)throws {;T7Kg.C
~$FgiW
HibernateException; UOwEA9q%
-%g&O-i\
} L=1~)>mP
|[lmW%
BA
9c-Ay
?-HLP%C('
vXP+*5d/ K
java代码: y {PUklq
Munal=wL
3gcDc~~=
/*Created on 2005-7-15*/ F4|Z:e,Hr
package com.adt.dao.impl; v.~uJ.T
8qi6>}A
import java.util.List; 6bXP{,}Gp
TjswB#
import org.flyware.util.page.Page; n( } zq
XX:?7:j}[8
import net.sf.hibernate.HibernateException; *Mg. *N
import net.sf.hibernate.Query; h jCkj(b
K~I%"r|l
import com.adt.dao.UserDAO; sPod)w?e
D') m8:>
/** 4*vV9*'!
* @author Joa 9jC>OZ0s
*/ +"HLx%k
public class UserDAOImpl extends BaseDAOHibernateImpl F}C.F
F6$QEiDu@
implements UserDAO { A3Lfh6O
jZ5 mpYUO
/* (non-Javadoc)
8FmRD
* @see com.adt.dao.UserDAO#getUserByName AzmISm
9:\YEs"
(java.lang.String) NGYUZ\m
*/ `]q>A']Dl
publicList getUserByName(String name)throws 6S2u%-]
{ejJI/o0
HibernateException { />EH]-|
String querySentence = "FROM user in class 6*({ZE
CI~P3"`]
com.adt.po.User WHERE user.name=:name"; b# RTHe&X
Query query = getSession().createQuery }0 BKKU +
-x)zyq6
(querySentence); <Z -d5D>
query.setParameter("name", name); 1l(_SD;90t
return query.list(); zv%9?:
} p903*F^[,
rpZ^R}B%*v
/* (non-Javadoc) Gd]!D~[1
* @see com.adt.dao.UserDAO#getUserCount() x^ J}]5{0
*/ |1@/gqa
publicint getUserCount()throws HibernateException { l?AWG&
int count = 0; \en}8r9cy
String querySentence = "SELECT count(*) FROM dg?[gD8!4&
N!u(G
user in class com.adt.po.User"; n>
>!dg Og
Query query = getSession().createQuery wy1xZQ<5
+$b_,s
(querySentence); wP <)
count = ((Integer)query.iterate().next ]0+5@c
x<S?"
()).intValue(); #:5vN-9?
return count; lg(*:To3B
} .YT&V
=y>g:}G7
/* (non-Javadoc) 0CTUcVM#9
* @see com.adt.dao.UserDAO#getUserByPage E[Rd=/P6
sUki|lP
(org.flyware.util.page.Page) "/O`#Do/
*/ h)MU^aP
publicList getUserByPage(Page page)throws X;hV+|Bo
)<vU F]e~
HibernateException { ,xJ1\_GI`
String querySentence = "FROM user in class k7 0o=}
Jp0*Y-*Y
com.adt.po.User"; UZ`G S$D@
Query query = getSession().createQuery |K H&,
%DKQ
(querySentence); yd-r7iq
query.setFirstResult(page.getBeginIndex()) Wd R ~
.setMaxResults(page.getEveryPage()); Q|O! cEW/
return query.list(); |Zn|?#F
} 9qHbV
9,M
[KT'aGK$
} D(m2^\O[
CflGj0oy8
~; emUU
\G!TC{6
"'@iDq%y
至此,一个完整的分页程序完成。前台的只需要调用 cr&sI=i
{!$E\e^d
userManager.listUser(page)即可得到一个Page对象和结果集对象 iEtnwSt
L~,x~sLd
的综合体,而传入的参数page对象则可以由前台传入,如果用 mX2(SFpJar
/]mfI&l+9
webwork,甚至可以直接在配置文件中指定。 ~ PO)>;
<Ag`pZ<s
下面给出一个webwork调用示例: RoG
`U
java代码: c']3N
z^KMYvH
g
zB8 @Wl
/*Created on 2005-6-17*/ " ^t3VjN
package com.adt.action.user; u+&t"B
-UHa;WH
import java.util.List; }i"\?M
4490l"
import org.apache.commons.logging.Log; :#?Z)oQpT
import org.apache.commons.logging.LogFactory; (4hCT*
import org.flyware.util.page.Page; sNet[y:O3
w;LIP!T#
import com.adt.bo.Result; Jj_ t0"
import com.adt.service.UserService; L=ala1{O
import com.opensymphony.xwork.Action; kb27$4mm
$rb
#k{
/** ?8g*"&cn
* @author Joa :r{;'[38
*/ GkhaB(btk'
publicclass ListUser implementsAction{ oi@/H\7j
jJ}3WJ
privatestaticfinal Log logger = LogFactory.getLog yc#0c[ZQu
lji&]^1
(ListUser.class); X0h`g)Bbf
8BL]]gT-I
private UserService userService; *gq~~(jH
Z'vic#
private Page page; O> 5xFz'm
PD-<D~7
privateList users;
q&j4PR{
<vMdfw"(
/* 4\cJ}p}LZ{
* (non-Javadoc) ~HW}Wik
* f.Uvf^T}2
* @see com.opensymphony.xwork.Action#execute() mHm"QBa!
*/ &2~c,] 9C
publicString execute()throwsException{ O?6ph4'
Result result = userService.listUser(page); 8"f Z>XQ
page = result.getPage(); b6@(UneVM
users = result.getContent(); Zj(2$9IU
return SUCCESS; |;G9K`8
} rF/k$_bFt
#s 4v0auK
/** /$q9
Kxb
* @return Returns the page. (}]ae*
*/ rq[+p
public Page getPage(){ d]89DdZk
return page; )_m#|U?Rex
} 2|LgUA?<
Ewfzjc
/** Kx-s95t
* @return Returns the users. N8]DW_bsB
*/ >uu]K
publicList getUsers(){ z A ~aiX
return users; %\ifnIQ
} o=&tT,z
p\"WX
/** p41TSALq
* @param page s.9)?<[
* The page to set. O|5Z-r0<
*/ _P^ xX'v
publicvoid setPage(Page page){ ,#NH]T`c1
this.page = page; C78V/{
} *dTI4k
o7qZy |\4S
/** qs["&\@
* @param users TQor-Cymz
* The users to set. '@{'T LMCi
*/ 2feiD?0
publicvoid setUsers(List users){ Vy-kogVt
this.users = users; u_;&+o2
} LD.^.4{c:
/2<1/[#
/** y; .U-}e1
* @param userService ,KfBG<3
* The userService to set. dbmty|d
*/ M%\=Fb
publicvoid setUserService(UserService userService){ 1 2Lc$\3P
this.userService = userService; I6jDRC0<
} ?3I93Bt7
} YH:murJMZ
=;) M+"
ogOUrJ}P
QSaJb?I
`egyk)"aM
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, _&U5 u
A9?h*/$
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 /]_a\x5Ss
;RmL'
么只需要: rA"><pH
java代码: PB
W.nm
B9Ha6kj
*c0\<BI
<?xml version="1.0"?> i uNBw]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork tn"n~;Bh?:
Hq>"rrVhx
1.0//EN" "http://www.opensymphony.com/xwork/xwork- b8>2Y'X
h
rksPK"s2
1.0.dtd"> 'ot,6@~x>
OYj4G?c
<xwork> viLK\>>
Ot^<:\<`G
<package name="user" extends="webwork- NV[_XXTv7
l6AG!8H
interceptors"> ^2|G0d@.:
0cpI2
<!-- The default interceptor stack name k~YZT 8
k=7+JI"J
--> "1-|ahW
<default-interceptor-ref h=1cD\^|qw
NIzxSGk|
name="myDefaultWebStack"/> 3RW3<n
7[b]%i
<action name="listUser" -UhSy>m
AXQG
class="com.adt.action.user.ListUser"> %+1;iuDL
<param _w'N
b6LwKUl
name="page.everyPage">10</param> jOE~?{8m
<result `X =2Ff
5@:c6(5$
name="success">/user/user_list.jsp</result> bR0 z$~
</action> R3[H#*gF<
AzfYw'^&9
</package> x c[BQ|P=
G T3wJQ5N
</xwork> :'t+*{ff
W{{{c2 .
VkD8h+)
gmU0/z3&
Gp PlO]
bM9:h
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ?puZqVu5
WN_i-A1G/h
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 J4xJGO
[xrM){ItW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 UP*\p79oO
nj@l5[
M<sY_<z
.2si[:_(p
=Y0>b4
我写的一个用于分页的类,用了泛型了,hoho .ZB/!WiF
B F,rZZL
java代码: VgoN=S
h
/. ^iT
B!#F!Wk"
package com.intokr.util; %U4w@jp
Ga%x(1U[&
import java.util.List; ,z*-93H1
ZgXn8O[a
/** YTtuR`
* 用于分页的类<br> Ao%;!(\I%
* 可以用于传递查询的结果也可以用于传送查询的参数<br> `2j \(N,
* nCj_4,O
* @version 0.01 ~MgU"P>
* @author cheng e/h2E dY
*/ ?;//%c8,.
public class Paginator<E> { bay7%[BLB
privateint count = 0; // 总记录数 f\Fk+)e@
privateint p = 1; // 页编号 :=<0Z1S
privateint num = 20; // 每页的记录数 e2onR~Cf
privateList<E> results = null; // 结果 j.5;0b_L^
9Xr @ll
/** RZV8{
* 结果总数 nhUL{ER
*/ $c WO`\XM
publicint getCount(){ ~(|~Ze>
return count; 2K8?S
} 1 o;*`
c04"d"$ x
publicvoid setCount(int count){ .hD2g"
this.count = count; \mBH6GS
} 0>E0}AvkT
c1,dT2:=
/** !Gphs`YI
* 本结果所在的页码,从1开始 P@u&~RN9f+
* A(xCW+h@)
* @return Returns the pageNo. (4U59<ie
*/ ) ny,vcU]
publicint getP(){ )ZU=`!4
return p; fO4e[g;G
} OZw<YR
7\q_^
/** E
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* if(p<=0) p=1 Cw=wU/)
* wc-ll&0Z
* @param p qlUw;{;p
*/ 7jb{E+DrG
publicvoid setP(int p){ &I[ITp6y0
if(p <= 0) I3 %P_oW'
p = 1; +dkbt%7M
this.p = p; )BuS'oB
} $rZ:$d.C
4zF|}aiQ
/** Wgh4DhAW
* 每页记录数量 lZ3o3"
*/ <z>K{:+>
publicint getNum(){ .?TPoqs7Z
return num; `VT0wAe2;
} $J~~.PUXQ
+Oae3VFf;
/** >gt_C'
* if(num<1) num=1 XZcT-w7
*/ xr2ew%&o
publicvoid setNum(int num){ u%^Lu.l_c
if(num < 1) DIk\=[{2q
num = 1; NZ\aK}?~!
this.num = num; !eoN
} F4m Q#YlrS
LNp%]*h
/** %^L:K5V
* 获得总页数 )8c`o
*/ CIM9~:\
publicint getPageNum(){ 8e'0AI_>
return(count - 1) / num + 1; ZOFhX$I
} a.|4`*1[;
JlR'w]d M,
/** $RQ7rL3g{
* 获得本页的开始编号,为 (p-1)*num+1 &h7q=-XU
*/ ,_66U;T
publicint getStart(){ mGQgy[gX
return(p - 1) * num + 1; N.J;/!%!
} Tl#Jf3XY}
XFeeNcqF
/** 2p( M`@
* @return Returns the results. '~-Lxvf'
*/ !;SpQ28
publicList<E> getResults(){ WC!b B
return results; * &j)"hX
} kRs24=
7]_lSYwrb
public void setResults(List<E> results){ K>k MKd1
this.results = results; -R!qDA"
} ,w.`(?I/
LE_1H>
public String toString(){ $*| :A
StringBuilder buff = new StringBuilder jafq(t
VV(>e@Bc4
(); 9o.WJ
buff.append("{"); 9T47U; _)
buff.append("count:").append(count); 4#5w^
buff.append(",p:").append(p); n9;+RhxA
buff.append(",nump:").append(num); UarU.~Uqi
buff.append(",results:").append ^n@.
p}KZ#"Q
(results); eSynw$F2N
buff.append("}"); Ae,-.xJ
return buff.toString(); &bx;GG\<4
} 8wz4KG3SK
%h**L'~``
} H|='|k5Y.
28[dTsd%
29"eu#-Qj