Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 NkoofhZ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pMDH
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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 G V=OKf#
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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 c+wuC,
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分页支持类: O&52o]k5l
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java代码: ]qMH=>pOsj
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package com.javaeye.common.util; *F|i&2
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import java.util.List; {sl~2#,}b1
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publicclass PaginationSupport { >^;(c4C
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publicfinalstaticint PAGESIZE = 30; ,Q+\h>I
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privateint pageSize = PAGESIZE; yW{mK
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privateList items; X;(oz]tr$
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privateint totalCount; YK7 \D:
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privateint[] indexes = newint[0]; nZ541o@t9
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privateint startIndex = 0; u*U_7Uw$
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public PaginationSupport(List items, int f>O54T .L.
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totalCount){ k+f1sV[4}
setPageSize(PAGESIZE); T^d#hl.U
setTotalCount(totalCount); 2'|XtSj
setItems(items); XRtyC4f
setStartIndex(0); IL2e6b
} wG;}TxrLS
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public PaginationSupport(List items, int g(KK9Unu
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totalCount, int startIndex){ ~37R0`C
setPageSize(PAGESIZE); 48H5_9>:
setTotalCount(totalCount); IN<:P
setItems(items); >G<4Ro"
setStartIndex(startIndex); f_~}X#._
} =obt"K%n
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public PaginationSupport(List items, int 'w'Dwqhmr
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totalCount, int pageSize, int startIndex){ Bl=nj.g
setPageSize(pageSize); f 5mY;z"
setTotalCount(totalCount); -e &$,R>;
setItems(items); ix(U:'{
setStartIndex(startIndex); h\/^Aa0
} 3L?WTS6(u
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publicList getItems(){ wEZ,49
return items; qK{|Q
} 5<!o{)I
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publicvoid setItems(List items){ PG\\V$}A(
this.items = items; r(PJ~8)(=
} )lQN)!.)
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publicint getPageSize(){ f:n] Exsy
return pageSize; UEN YJ*tnP
} !1D%-=dWX
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publicvoid setPageSize(int pageSize){ "ugX
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this.pageSize = pageSize; 5JO[+>
} zC<'fT/rG
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publicint getTotalCount(){ N5[_a/
return totalCount; &*X3ch
} (PRaiE
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publicvoid setTotalCount(int totalCount){ H?rSP0.
if(totalCount > 0){ cZPbD;e:
this.totalCount = totalCount; 1-4
int count = totalCount / Q,OkO?uY
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pageSize; 'hxs((['\
if(totalCount % pageSize > 0) ;5&k/CB1
count++; '=KuJ0`nE9
indexes = newint[count]; Wpiv1GZ%c8
for(int i = 0; i < count; i++){ NvXj6U*%
indexes = pageSize * |U8>:DE l
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i; p*A^0DN'Fn
} e}{8a9J<%_
}else{ ~,(0h:8
this.totalCount = 0; 113Z@F
} SIKk|I)
} d)`nxnbMeM
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publicint[] getIndexes(){ 9itdRa==
return indexes; n,CD4Nv
} _Ym&UY.u#
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publicvoid setIndexes(int[] indexes){ ^G]KE8
this.indexes = indexes; M>`?m
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} DR.3
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publicint getStartIndex(){ Z\ "Kd
return startIndex; .F{}~K]
} { Hktu|
@t{{Q1
publicvoid setStartIndex(int startIndex){ yVbg,q'?
if(totalCount <= 0) @ef//G+Z"
this.startIndex = 0; {jj]K.&
elseif(startIndex >= totalCount) ;`X`c
this.startIndex = indexes J>,'P^
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[indexes.length - 1]; v*vub#wP
elseif(startIndex < 0) D'HL /[@`
this.startIndex = 0; K8yWg\K
else{ GV `idFd
this.startIndex = indexes umq$4}T'$
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[startIndex / pageSize]; !?tu!
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} $i1>?pb3
} AxG?zBTFx
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publicint getNextIndex(){ :epitpJ
int nextIndex = getStartIndex() + e8WPV
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pageSize; I1eb31<
if(nextIndex >= totalCount) hr/xpQW
return getStartIndex(); mI_ 6f~
else B1 jH.(
return nextIndex; +iZ@.LI
} UgOGBj,&5W
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publicint getPreviousIndex(){ S4@117z5
int previousIndex = getStartIndex() - ~|$) 1
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pageSize; xc3Ov9`8%
if(previousIndex < 0) M8^ziZY
return0; (o6A?37i
else K4K3<Pg
return previousIndex; -7C=- \]
} (AyRs7Dkn
hs -}:^S`
} X:zyzEhS
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抽象业务类 qB`0^V
java代码: (>)+;$Dr,\
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/** I%VV4,I&pK
* Created on 2005-7-12 7@e[:>e
*/ U3VsMV*Y
package com.javaeye.common.business; j3V"d 3)
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import java.io.Serializable; Vt$ $ceu
import java.util.List; T8M[eSbZ
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import org.hibernate.Criteria; mtHi9).,y|
import org.hibernate.HibernateException; Ri%Of:zZ
import org.hibernate.Session; "~i#9L/H
import org.hibernate.criterion.DetachedCriteria; :#"OCXr
import org.hibernate.criterion.Projections; l#J>It\
import $D2Ain1
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org.springframework.orm.hibernate3.HibernateCallback; @/ovdf{
import [3bwbfHhi
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org.springframework.orm.hibernate3.support.HibernateDaoS ,M9hb<:m
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upport; .,iw2:
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import com.javaeye.common.util.PaginationSupport; (t"YoWA#m
PHB\)/
public abstract class AbstractManager extends *<
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HibernateDaoSupport { _oyL*Cb
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privateboolean cacheQueries = false; k%bTs+]*
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privateString queryCacheRegion; Ug[F3J|Mu
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publicvoid setCacheQueries(boolean 36D,el In
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cacheQueries){ ::Ve ,-0
this.cacheQueries = cacheQueries; n$\6}\k
}
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publicvoid setQueryCacheRegion(String u{y5'cJ{
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queryCacheRegion){ H"Em|LX^
this.queryCacheRegion = :fMM-?s]
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queryCacheRegion; ^LAS9K1.
} &opH\wa
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publicvoid save(finalObject entity){ uma9yIk
getHibernateTemplate().save(entity); t3h \.(mq
} !un"XI0`t<
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publicvoid persist(finalObject entity){ epm8N /
getHibernateTemplate().save(entity); l.t. ,:
} '\3.isTsx
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publicvoid update(finalObject entity){ hrtN.4p[
getHibernateTemplate().update(entity); %>QSeX
} e[Ul"pMvS`
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publicvoid delete(finalObject entity){ @%okaj#IO
getHibernateTemplate().delete(entity); ,jdKcWy'
} bgx5{!A
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publicObject load(finalClass entity, 1,sO =p)Yg
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finalSerializable id){ uc
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return getHibernateTemplate().load ieK'<%dxF
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(entity, id); z@40g)R2A
} SZ1pf#w!
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publicObject get(finalClass entity, 'J<zVD}0
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finalSerializable id){ Hwi7oXP
return getHibernateTemplate().get Mdq'> <ajL
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(entity, id); Ymh2qGcj]8
} a>e
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publicList findAll(finalClass entity){ ;@$, "
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return getHibernateTemplate().find("from ;?[ +vf")
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" + entity.getName()); AFnlt
} @ F"ShT0
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publicList findByNamedQuery(finalString !N2 n@bo
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namedQuery){ w2_I/s6B
return getHibernateTemplate >5Rw~
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().findByNamedQuery(namedQuery); dXSb%ho
} 2T?1X{g
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publicList findByNamedQuery(finalString query, ErUk>V
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finalObject parameter){ eFI9S.6
return getHibernateTemplate >WG91b<Xq
*v-xC5L1\
().findByNamedQuery(query, parameter); E;*TRr><
} $+yQ48Wq
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publicList findByNamedQuery(finalString query, UVi/Be#|
9(\N+
finalObject[] parameters){ I;PO$T
return getHibernateTemplate <.]& FPJ
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().findByNamedQuery(query, parameters); N1zrfn-VU
} E8V\J
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publicList find(finalString query){ $zH0$aOx
return getHibernateTemplate().find YV+dUvz
s%re>)=|
(query); )1'_g4
} T_
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publicList find(finalString query, finalObject ;-w PXXR
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parameter){ (4gQe6tA
return getHibernateTemplate().find o%s}jBo}
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(query, parameter); @g` ,'r
} h1d0{
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public PaginationSupport findPageByCriteria JHOBg{Wg
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(final DetachedCriteria detachedCriteria){ nqW:P$
return findPageByCriteria b-gVRf#F
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); [Cr~gd+q
} 8-#2?=
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public PaginationSupport findPageByCriteria E^ti!4{<
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(final DetachedCriteria detachedCriteria, finalint \Xp"I5
{N`<e>A]{
startIndex){ +=xRr?F
return findPageByCriteria f@X*Tlx^|
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(detachedCriteria, PaginationSupport.PAGESIZE, =C}<0<"iF
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startIndex); zIm!8a
} h2*&>Mc
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public PaginationSupport findPageByCriteria q/G5aO*
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(final DetachedCriteria detachedCriteria, finalint `cRB!w=KHV
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pageSize, *XR~fs?/*W
finalint startIndex){ }J
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return(PaginationSupport) I=-;*3g6
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getHibernateTemplate().execute(new HibernateCallback(){ a-hGpYJJG
publicObject doInHibernate H( m+rk
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(Session session)throws HibernateException { (!=aRC.-
Criteria criteria = pZn%g]nRD
,_-*/- 7;8
detachedCriteria.getExecutableCriteria(session); d8I:F9
int totalCount = ]jrxrUl
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((Integer) criteria.setProjection(Projections.rowCount }e @-[RJ!
nJ@hzK.
()).uniqueResult()).intValue(); 9D21e(7X
criteria.setProjection qa?y lR"kA
pdu
(null); ' qVa/GJ
List items = N/=3Bs0y-
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criteria.setFirstResult(startIndex).setMaxResults S!cXc/H-R
1i2O]e!
(pageSize).list(); p$<qT^]&
PaginationSupport ps = a06q-3zw
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new PaginationSupport(items, totalCount, pageSize, P
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startIndex); h!]A(T\J
return ps; K@hUif|([
} 'kK%sE
}, true); oPBjsQ
} `7ZJB$7D|*
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public List findAllByCriteria(final gV;GC{pY
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DetachedCriteria detachedCriteria){ /L^dHI]Q
return(List) getHibernateTemplate 2N]s}/l
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().execute(new HibernateCallback(){ xx8na8
publicObject doInHibernate V|`|CVFo]
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(Session session)throws HibernateException { kRPg^Fw"Vw
Criteria criteria = >AJ|F)
@9a=D<'>
detachedCriteria.getExecutableCriteria(session); s,x]zG"
return criteria.list(); A@r,A?(
} $Plk4 o*g
}, true); !HYqM(|{.
} xcA:Q`c.{
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public int getCountByCriteria(final 2D"/k'iA
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DetachedCriteria detachedCriteria){ ,,gYU_V
Integer count = (Integer) !NjE5USi
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getHibernateTemplate().execute(new HibernateCallback(){ Q!v[b{]8
publicObject doInHibernate b.&YUg[#
{'(8<n57
(Session session)throws HibernateException { cO9Aw !
Criteria criteria = 2hP8ZfvIR
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detachedCriteria.getExecutableCriteria(session); Is[0ri
return ":ycyN@g
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criteria.setProjection(Projections.rowCount {{\HU0g>&
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()).uniqueResult(); #4>F%_
} ` 0F
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}, true); yM@cml6Ox
return count.intValue(); 1wt]J!hgV
} X*Zv,Wm
} $)!Z"2T
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用户在web层构造查询条件detachedCriteria,和可选的 3$54*J
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 }{J8U2])k
}: e9\r)
PaginationSupport的实例ps。 l<+k[@Vox
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ps.getItems()得到已分页好的结果集 ~4 ab\hq
ps.getIndexes()得到分页索引的数组 :|Cf$2k7
ps.getTotalCount()得到总结果数 9tO_hhEQ@
ps.getStartIndex()当前分页索引 Ai;Pht9qi
ps.getNextIndex()下一页索引 -5K/ cK
ps.getPreviousIndex()上一页索引 2X`M&)"X
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 K9R[
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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 .@'Vz;&mQ
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一下代码重构了。 5>
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我把原本我的做法也提供出来供大家讨论吧: X9 R-GT
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首先,为了实现分页查询,我封装了一个Page类: Iu8=[F>
java代码: P\JpE
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/*Created on 2005-4-14*/ rYl37.QE
package org.flyware.util.page; !wgj$5Rw.
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/** /.r($Sg^
* @author Joa B}W^s;h
* 1K>4i. X
*/ Rjf|
publicclass Page { 8'y|cF%U
8Bhng;jX
/** imply if the page has previous page */ u8*0r{kOH
privateboolean hasPrePage; mN{$z<r
dn Xc- <
/** imply if the page has next page */ ;1KhUf;&F
privateboolean hasNextPage; 3;A1[E6K
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/** the number of every page */ jVDNThm+
privateint everyPage; 1na[=Q2
g!$
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/** the total page number */ a
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privateint totalPage; ^P[*yf
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/** the number of current page */ 7?Fl [FW$
privateint currentPage; ;.Kzc3yz}
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/** the begin index of the records by the current W6pS.}
jV(ISD
query */ B~^\jRd"
privateint beginIndex; ^JTfRZ:a
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/** The default constructor */ R~`Y6>o~9:
public Page(){ QwhPN'U
;BqX=X+#
} E$cr3 t7Xy
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/** construct the page by everyPage /<mc~S7
* @param everyPage \sk,3b-&'
* */ [-l^,,E
public Page(int everyPage){ Uc4r
this.everyPage = everyPage; J(Bn
n
} ~Sh}\&3p
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/** The whole constructor */ \R~Lf+q
public Page(boolean hasPrePage, boolean hasNextPage, !n7?w@2a'
5+U~ZW0|+
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int everyPage, int totalPage, :7R\"@V4
int currentPage, int beginIndex){ sIyLW
this.hasPrePage = hasPrePage; U}UIbJD*=
this.hasNextPage = hasNextPage; ? f%@8%px
this.everyPage = everyPage; (k[<>$hL*
this.totalPage = totalPage; eN/Jb;W
this.currentPage = currentPage; IcA]<}0!"v
this.beginIndex = beginIndex; r@_;L>
} 8'zwyd3
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/** _%t w#cM
* @return U<*dDE~z
* Returns the beginIndex. *@O;IiSE
*/ 9qw~]W~Nm
publicint getBeginIndex(){ ^!A{ 4NV
return beginIndex; }Iu 6]?|'
} "$WZd
G",+jR]
/** D,NjDIG8
* @param beginIndex "DUL} "5T
* The beginIndex to set. 5vS'Qhc
*/ lY6U $*9c
publicvoid setBeginIndex(int beginIndex){ j*CnnM#n
this.beginIndex = beginIndex; #oHHKl=M
} 'HOt?lpu!
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/** cM55
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* @return er 97&5
* Returns the currentPage. P|G:h&
*/ n|(Y?`(
publicint getCurrentPage(){ 7Q^t(
return currentPage; vZ*593C8
} -q-%)f
k(T/ydrw
/** W{k}ogI;
* @param currentPage ?A]:`l_"
* The currentPage to set. aa$+(
*/ hGPjH=^EM
publicvoid setCurrentPage(int currentPage){ yM>c**9
this.currentPage = currentPage; J H6\;G6
} Lw3Z^G
eQMY3/#
/** CnJO]0Op3
* @return ?:UDK?
* Returns the everyPage. vh((HS-)
*/ 2 &R-zG
publicint getEveryPage(){ :c
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return everyPage; b8>rUGA{
} U*)pUJ{&t
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/** Zsaz#z|xW
* @param everyPage qRTy}FU1
* The everyPage to set. uZi]$/ic
*/ )bqO}_B
publicvoid setEveryPage(int everyPage){ y6;A4p>
this.everyPage = everyPage; N{f RZN
} z~Gi/Ln
`NrxoU=
/** zxXm9zrLo
* @return "`16-g97
* Returns the hasNextPage. ]>&au8
*/ Rs7=v2>I
publicboolean getHasNextPage(){ &d=j_9
return hasNextPage; ~fEgrF d
} c}lUP(Ss
F?TAyD*
/** W,}C*8{+
* @param hasNextPage wQDKv'zU1
* The hasNextPage to set. 1)H+iN|im/
*/ {i3]3V"Xp
publicvoid setHasNextPage(boolean hasNextPage){ `5Q0U%`W
this.hasNextPage = hasNextPage; /z`LB
} zuXJf+]
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/** }~yhkt5K
* @return G,%R`Xns
* Returns the hasPrePage. G|v{[>tr
*/ rD
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publicboolean getHasPrePage(){ ~gmj/PQ0
return hasPrePage; ^lf{IM-Y
} o|$l+TC
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/** Fd9ypZs
* @param hasPrePage d_]zX;_
* The hasPrePage to set. RoT}L#!!
*/ N
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publicvoid setHasPrePage(boolean hasPrePage){ 89@gYA"Su
this.hasPrePage = hasPrePage; YqrieDFay!
} 3Jf_3c
l>Z"y\l=
/** *?+E?AGe
* @return Returns the totalPage. UOi8>;k`
* "}Vow^vb
*/ >d&B:
publicint getTotalPage(){ &V:iy
return totalPage; gYw4YP0Gz
} z`y!C3w<
ilHZx2k
/** EE=!Y NP]
* @param totalPage JT#jJ/^
* The totalPage to set. {rBS52,Z#
*/ p~6/
publicvoid setTotalPage(int totalPage){ a^>0XXr}Y
this.totalPage = totalPage; TDq(%IW
} S2'./!3yv
Qk*`9
} ?zM]p"M
xp.~i*!`
3{O^q/R
'
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+:+q,0~*]
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 ^9UKsy/q
}vgeQh-G
个PageUtil,负责对Page对象进行构造: uzr(gFd
java代码: Q,S~+bD(z
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/*Created on 2005-4-14*/ ]nY,%XE
package org.flyware.util.page; jhOQ)QE|
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import org.apache.commons.logging.Log; f.-b.nNf
import org.apache.commons.logging.LogFactory; FCgr
>08'+\~:b
/** * G!C 'w\$
* @author Joa XvETys@d
* F<39eDNpz
*/ -|YG**i/
publicclass PageUtil { )!z<q}i5
n** W
privatestaticfinal Log logger = LogFactory.getLog [T<nTB# w
f~
kz=R=
(PageUtil.class); 4+"2K-]
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/** nLicog)!I
* Use the origin page to create a new page H0r@dn
* @param page I7,5ID4pn
* @param totalRecords R~
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* @return P'MfuTtT&
*/ )_BQ@5NK
publicstatic Page createPage(Page page, int (?4m0Sn>#h
.5*5S[
totalRecords){ jwhc;y
return createPage(page.getEveryPage(), dxfF.\BFDn
/vO8s??
page.getCurrentPage(), totalRecords); 8T-/G9u
} cuzU*QW"g
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/** /6",#B}%b
* the basic page utils not including exception |7ct2o~un
xU<WUfS1
handler W>W b|W
* @param everyPage ?"04u*u3
* @param currentPage )}w2'(!X8
* @param totalRecords PgHe;^?j
* @return page 5argw+2s4$
*/ tZ\e:AAi
publicstatic Page createPage(int everyPage, int m' HAt~
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currentPage, int totalRecords){ 89n\$7Ff9
everyPage = getEveryPage(everyPage); &Z'3n9zl
currentPage = getCurrentPage(currentPage); ETZE.a
int beginIndex = getBeginIndex(everyPage, >V1vw7Pa
+guCTGD:
currentPage); 3ScOJo
int totalPage = getTotalPage(everyPage, ,6VY S\a3
r)<c
~\0 7
totalRecords); gOb"-;Zw
boolean hasNextPage = hasNextPage(currentPage, M]|tXo$?
t^Z-0jH
totalPage); kA/4W^]Ws
boolean hasPrePage = hasPrePage(currentPage); CZZwBt$P
28 Q\{Z.
returnnew Page(hasPrePage, hasNextPage, vo(riHH
everyPage, totalPage, p.@kv
currentPage, -So$f-y
R`
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beginIndex); '_ZiZ4O
} T8^`<gr.
Ob!NC&
privatestaticint getEveryPage(int everyPage){ wCQ.?*7-9Q
return everyPage == 0 ? 10 : everyPage; qkXnpv
} ~cr##Ff5
iy!SqC
privatestaticint getCurrentPage(int currentPage){ ]?S@g'Jd0Q
return currentPage == 0 ? 1 : currentPage; A_8Xhem${
} Ql#y7HW
/aV;EkyO,
privatestaticint getBeginIndex(int everyPage, int f?JP=j
?kM2/a"{G
currentPage){ 5nV IC3N+1
return(currentPage - 1) * everyPage; M:M"7>:
} &c[ISc>N{
Uv) B
privatestaticint getTotalPage(int everyPage, int 7m$EZTw?
Z1}@N/>>
totalRecords){ NI
r"i2
int totalPage = 0; (zr2b
=0t<:-?.-
if(totalRecords % everyPage == 0) :%[mc-6.
totalPage = totalRecords / everyPage; /6y9u}
else Y~TD)c=
totalPage = totalRecords / everyPage + 1 ; '2z1$zst,#
^V}c8 P|
return totalPage; ]A=yj@o$xN
} 8 /vGA=
x$hT+z6DUC
privatestaticboolean hasPrePage(int currentPage){ mV'-1
return currentPage == 1 ? false : true; NoOrQ m
} O2qy[]km
6n A/LW\x
privatestaticboolean hasNextPage(int currentPage, P(%^J6[>
fK|P144
int totalPage){ k*4!rWr0r&
return currentPage == totalPage || totalPage == %ZsdCQc{`
HT:V;?"
0 ? false : true; ^>/~MCyM.
} XjXz#0nR
b|-}?@&7&q
SPT?Tt
} W"Tj.oCUG
#=V\WQb
:u]QEZ@@
gb{8SG5ac
:\Q#W4~p
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。 e_YTh^wU
zx/$
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 FLo`EE":O(
7#&e0fw/I
做法如下: 8S`
j6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;w7s>(ITZ
h_HPmh5
的信息,和一个结果集List: {TXfi'\
java代码: yUjkRT&h
(u4'*[o\t
7NvnCs
/*Created on 2005-6-13*/ 3a?|}zr4
package com.adt.bo;
od)ssL&E~
[]jbzVwS2
import java.util.List; esM r@Oc
L1#_
import org.flyware.util.page.Page; s:K'I7_#@
?bAv{1dvT=
/** s<+;5, Q|
* @author Joa =O/v]B8"
*/ *C);IdhK%y
publicclass Result { Tb:6IC7="
Pcjrv:0$
private Page page; 7,s5Gd-
LAFxeo
private List content; -^Qm_lN
"$/1.SX;]
/** Vx{
* The default constructor O\SH;y,N
*/ m3~_uc/+D
public Result(){ O"X:3srJ`
super(); V.%LA.8
} fK _uuw4
'#C5m#v
/** ce[
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* The constructor using fields `mH]QjAO
* v\@pZw=x
* @param page Jj/}GVNc7
* @param content (tyky&$!
*/ GExr] 2r
public Result(Page page, List content){ kl1/(
this.page = page; ;|`<B7xf
this.content = content; }eF
r,bJ
} g[*"LOw
S17;;w0
/** \ Q^grX
* @return Returns the content. ^/VnRpU
*/ +z[+kir
publicList getContent(){ "@^Q"RF
return content; &>!-67
} f@gvDo]Y
)PkW,214#
/** @?jtB
* @return Returns the page. ~0h@p4
*/ &=f?:UZ%
public Page getPage(){ Be9,m!on
return page; xs&xcRR"
} q6ZewuV.
(I`lv=R"j
/** `v-O 4Pk
* @param content *\@RBJGF
* The content to set. JVGTmS[3
*/ &Yo|Pj
public void setContent(List content){ FJ^\K+;
this.content = content; +f%"O?
} UM`{V5NG#
*$5p,m6G
/** /+*N.D'`t,
* @param page r\cY R}v
* The page to set. 1]9w9!j
*/ eY-h<K)y
publicvoid setPage(Page page){ R={#V8D~
this.page = page; %NfXe[T
} 3 yw$<lm
} CiGXyhh
MsBm0r`a
IMncl=1
r{B28'f[
B;S'l|-?
2. 编写业务逻辑接口,并实现它(UserManager, #
E_S..
*?*~<R
UserManagerImpl) vaJl}^T
java代码: ^BM !TQ%!
TtF+~K
lT*@f39~g
/*Created on 2005-7-15*/ ][b|^V
package com.adt.service; '9=b@SaAj
\#xq$ygg
import net.sf.hibernate.HibernateException; a]Pw:lT
h@Jg9AM
import org.flyware.util.page.Page;
x.4z)2MO
OrYN-A4{
import com.adt.bo.Result; `qYiic%
^{{a
v?h
/**
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* @author Joa Bz <I7h
*/ )0/*j]Kf
publicinterface UserManager { nF_q{e7
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public Result listUser(Page page)throws L N
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j "'a5;Sy
HibernateException; a5R.
\a<q
MPDRMGR@i
} h_{f_GQ"
l
S3LX
L"/?[B":
)bR0>3/
BWvM~no
java代码: x.Egl4b3
%)r:!R~R
J
<;xkT1x
/*Created on 2005-7-15*/ iCA-X\E
package com.adt.service.impl; lVQE}gd%m
39hep8+
import java.util.List; ^N[ Cip}8
LT
Pr8^
import net.sf.hibernate.HibernateException; hRRxOr#*$
,(a~vqNQW3
import org.flyware.util.page.Page; ]{q=9DczG(
import org.flyware.util.page.PageUtil; Nf<f}`
Lui6;NY
import com.adt.bo.Result; Q(cLi:)X2
import com.adt.dao.UserDAO; e@
D}/1~=
import com.adt.exception.ObjectNotFoundException; mI!iSVqr
import com.adt.service.UserManager; iLIb-d?!a&
vPGUE`!D+
/** _@y uaMoW=
* @author Joa ||Owdw|{
*/ !yPy@eP~
publicclass UserManagerImpl implements UserManager { OdZ/ \_Z
%qz-b.
private UserDAO userDAO; ;y. ;U#O
\Cu=Le^
/** k(pJVez
* @param userDAO The userDAO to set. 1;1;-4k7I
*/ YJMs9X~3
publicvoid setUserDAO(UserDAO userDAO){ l"A/6r!Dp
this.userDAO = userDAO; >\^oCbqF}~
} Pj]^p{>
(3mL!1\
/* (non-Javadoc) p<(a);<L
* @see com.adt.service.UserManager#listUser @'}2xw[eU
]7cciob
(org.flyware.util.page.Page) @IsUY(Gu
*/ ?4U4o<
public Result listUser(Page page)throws S*=^I2;
LdH1sHy*d`
HibernateException, ObjectNotFoundException { 3o[(pfcU
int totalRecords = userDAO.getUserCount(); oJ
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if(totalRecords == 0) m3Wc};yE*Q
throw new ObjectNotFoundException W{.:Cf9
$*G3'G2'iS
("userNotExist"); p0 X%^A,4
page = PageUtil.createPage(page, totalRecords); zl6]N3+4
List users = userDAO.getUserByPage(page); $.pCoS]i
returnnew Result(page, users); =WUL%MfW
} vR:#g;mnk
D.:`]W|
} s|H7;.3gp
Pe,k y>ow
TK18U*z7J
S+~;PmN9qL
x%r$/=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 q[VQ?b~9
$(;Ts)P
询,接下来编写UserDAO的代码: Ycm .qud
?
3. UserDAO 和 UserDAOImpl: ~EY)c~H
java代码: "hI"4xSg
K"XwSZ/
T@.+bD
/*Created on 2005-7-15*/ &Pm@+ML*x
package com.adt.dao; P$Vh{]4i{
WN{8gL&y
import java.util.List; ^8~TsK~
8 <;.[l
import org.flyware.util.page.Page; DvQV_D
J.:
import net.sf.hibernate.HibernateException; `Wjq$*
C(v'7H{4cW
/** #K:iB*
* @author Joa 1="]'!2Is
*/ ?]Hs~n-
publicinterface UserDAO extends BaseDAO { (^FMm1@T
9)]`le
publicList getUserByName(String name)throws 0@b<?Ms9
$peL1'Evo
HibernateException; XrTc5V
h ChO
publicint getUserCount()throws HibernateException; ]}].Aq
NpZ'pBl
publicList getUserByPage(Page page)throws 9ThsR&h3
w9GY/]
HibernateException; -M6vg4gf
EiC["M'}
} g]HxPq+O
]kmAN65c
/<LjD
p gLhxc:
N?{Zrff2"O
java代码: 9NVtvBA
[ _xOz4`%
q1 q~%+Jy
/*Created on 2005-7-15*/ #UymD-yII
package com.adt.dao.impl; Z"Hq{?l9
:RB7#v={
import java.util.List; *8a[M{-X
=v\}y+
Yh
import org.flyware.util.page.Page; /_cpSq
2& Hl
wpx
import net.sf.hibernate.HibernateException; 6zU0 8z0-
import net.sf.hibernate.Query; rt vLLOIO
|>j^$^l~
import com.adt.dao.UserDAO; 2BO H8Mp9
gsQn@(;
/** [7DU0Xg7
* @author Joa W3\+51P
*/
A ;`[va
public class UserDAOImpl extends BaseDAOHibernateImpl CpN*1s})d
XU}i<5
implements UserDAO { \)\n5F:Zu
E5P.x^
/* (non-Javadoc) nY1PRX\
* @see com.adt.dao.UserDAO#getUserByName xP1D 9
aMydeTCHi
(java.lang.String) ZT&[:>upR
*/ Uhh[le2 %
publicList getUserByName(String name)throws !?i9fYu
2xuU[
HibernateException { Y(rQ032s
String querySentence = "FROM user in class (0 t{
Dy. |bUB!f
com.adt.po.User WHERE user.name=:name"; E"BW-<_!
Query query = getSession().createQuery S?v;+3TG
\J(~
Nv5!
(querySentence);
2i6P<&@
query.setParameter("name", name); ^v;8 (eF
return query.list(); Gv)*[7
} f~=e
}o
GMF~
/* (non-Javadoc) "0G)S'
* @see com.adt.dao.UserDAO#getUserCount() mp(:D&M
*/ r7U[QTM%
publicint getUserCount()throws HibernateException { O&.gc p!
int count = 0; tJd/uQJ
String querySentence = "SELECT count(*) FROM ri"=)]
x51p'bNy
user in class com.adt.po.User"; !_o1;GzK
Query query = getSession().createQuery 2V9"{F?
YL;*%XmAG
(querySentence); =}0>S3a.7
count = ((Integer)query.iterate().next \@ZD.d#
q,Nqv[va
()).intValue(); 9~f
RYA*
return count; 9WoTo ,q
} K)`l >o1
W-RshZ\
/* (non-Javadoc) uZ1G,9
* @see com.adt.dao.UserDAO#getUserByPage Sf`?j
Tt0]G_
(org.flyware.util.page.Page) 0[Zs8oRiI
*/ czo*_q%
publicList getUserByPage(Page page)throws }`$({\^w
0F 4%Xz
HibernateException { Y5IQhV.
String querySentence = "FROM user in class zq^eL=%:
kafj?F
com.adt.po.User"; n)]u|qq
Query query = getSession().createQuery F JxH{N6a
uhmSp+%
(querySentence); <e8Ux#x/
query.setFirstResult(page.getBeginIndex()) |2X+( F Ed
.setMaxResults(page.getEveryPage()); L|2WTyMU
return query.list(); >Cr'dKZ}
} HFj@NRE6
a=^>A1=
} h7\16j
9@p+g`o
g7LS
7tT L,Nxe
VelX+|w
至此,一个完整的分页程序完成。前台的只需要调用 ^MZ9Zu_
YQfQ[{kp
userManager.listUser(page)即可得到一个Page对象和结果集对象 ( v=Z$#l
|Tl2r,(+R
的综合体,而传入的参数page对象则可以由前台传入,如果用 6x_D0j%^]
-v WXL
webwork,甚至可以直接在配置文件中指定。 TbR
Ee;1
1,G f;mcQ
下面给出一个webwork调用示例: O`0A#h&No
java代码: DVyxe}
a*@4W3;7
/{X2:g {
/*Created on 2005-6-17*/ T
3+lYE
package com.adt.action.user; pXxpEv
9d,2d5Y
import java.util.List; ? m.Ry
Je~Ybh
import org.apache.commons.logging.Log; ]M9r<x*
import org.apache.commons.logging.LogFactory; ZEU/6.
import org.flyware.util.page.Page; ^5gB?V,
|f&=9%
import com.adt.bo.Result; {B6tGLt#bf
import com.adt.service.UserService; `OyYo^+D|.
import com.opensymphony.xwork.Action; Rwz (20n\^
ApAHa]Ccp
/** (=i+{
3`|
* @author Joa DKf:0E8
*/ O>L
5
dP
publicclass ListUser implementsAction{ >_?Waz%
(V+iJ_1g{
privatestaticfinal Log logger = LogFactory.getLog +D+Rf,D
w=75?3c7 F
(ListUser.class); k<NEauQ
Z0%Qy+%
private UserService userService; 7(= 09z
K~>ESMZ5
private Page page; 3/((7O[
< G:G/
privateList users; ob.=QQQs
{5gh.
/* -r"h[UV)
* (non-Javadoc) iYxpIqWw
* 8(A+"H(
* @see com.opensymphony.xwork.Action#execute() gkDlh{
*/ _"%-=^_
publicString execute()throwsException{ a)Ca:p
Result result = userService.listUser(page); B mxBbg
page = result.getPage(); APu cA
users = result.getContent(); yY42+%P
return SUCCESS; |nj,]pA
} Vam4/6
4 '6HX#J
/** VpkkiN
* @return Returns the page. ({AqL#x`u
*/ J'>i3eLq
public Page getPage(){ tO^KCnL
return page; ~<#!yRy>r
} U#!f^@&AB
`[Xff24(eb
/** !,< )y}L^)
* @return Returns the users. /!Ng"^.e
*/ %7~~*_G
publicList getUsers(){ H#;-(`F
return users; 1tQl^>r16
} <);Nc1
$R[ggH&
/** AR-&c 3o
* @param page Xy(o0/7F9
* The page to set. u`vOKajpH$
*/ wfxg@<WR
publicvoid setPage(Page page){ Z>H
y+Q4
this.page = page; dLMKfh/4Q
} 2,X~a;+
U&\8~h
/** <X_I`
* @param users 3o=K?eOdg
* The users to set. pkL&j<{
*/ Yw\PmRL"p
publicvoid setUsers(List users){ >)3[CU,
this.users = users; ,1+)qv#|i
}
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@dzO{)
/** AI&Bv
* @param userService T~rPpi&
* The userService to set. `'{>2d%\g
*/ Q,mmHw.`J
publicvoid setUserService(UserService userService){ q^_PR|
this.userService = userService; v}$KlT
} p=65L
}
!Z'x h +
.*s1d)\:
dt(#|8i%
Rx22W:S=C.
Ok=RhoZZ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, CN$wlhs
;r_YEPlZ
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 2R!1Vl
BQcrF{q
么只需要: n%>c4*t
java代码: i0%S6vmaS
7aJLC!
^$7Lmd.qI
<?xml version="1.0"?> ~EVD NnHEr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork a;Q.R
j~eYq
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 6mnj!p]3
z;_fO>u:
1.0.dtd"> y-TS?5Dr]
L`$MOdF{_
<xwork> ^nYS@
",c(cYVW
<package name="user" extends="webwork- i%8I (F
w>:~Ev]
interceptors"> ]e'Ol$3U9=
"?Eh_Dw
<!-- The default interceptor stack name S'NZb!1+
X/_e#H0
--> w~eF0{h
<default-interceptor-ref QGYO{S
?X1vU0c
name="myDefaultWebStack"/> 3JiJ,<,7
#4ZDY,>Xi#
<action name="listUser" xbFoXYqgP
ZLBv\VQ
class="com.adt.action.user.ListUser"> )2|'`
<param =#AeOqs( q
cvR|qHNX
name="page.everyPage">10</param> P| o_/BS
<result Lzzf`jN]
MVW2%6
name="success">/user/user_list.jsp</result> 7T]}<aK<c[
</action> dsKEWZ
=
3McBTa!
</package> \>8"r,hG|
+1Ha,Ok
</xwork> li4rK<O
,!BiB*
T [
`t?,
?8g[0/
T#.5F7$u
l I&%^>
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 uFM]4v3
uUUj?%
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。 T-)Ur/qp
@;iW)a_M
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 6% @@~"
}+KSZ,
n{dl-P
o*2TH2
sjpcz4|K
我写的一个用于分页的类,用了泛型了,hoho bE-{
U/;
`B+P$K<