Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $1bzsB|^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 w(!COu
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 [^\HP]*Q{
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 I8
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分页支持类: ^ZDpG2(zk
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java代码: d0G d5%
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package com.javaeye.common.util; G`FY[^:
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import java.util.List; je5GZFQw
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publicclass PaginationSupport { :<R"Kk@
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publicfinalstaticint PAGESIZE = 30; =.t3|5U8
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privateint pageSize = PAGESIZE; !2]'S=Y
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privateList items; Ydh+iLjhx
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privateint totalCount; YC =:W
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privateint[] indexes = newint[0]; M IR))j;
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privateint startIndex = 0; c"`CvQO64
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public PaginationSupport(List items, int fzW!-
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totalCount){ U$wD'v3pw
setPageSize(PAGESIZE); t}f,j^`e
setTotalCount(totalCount); #0 eop>O
setItems(items); QK(w2`
setStartIndex(0); xcE<|0N
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} ,2`FSL%J
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public PaginationSupport(List items, int 05Y4=7,!
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totalCount, int startIndex){ 9"b =W@
setPageSize(PAGESIZE); 9{XV=a v
setTotalCount(totalCount); uN9J?j*ir
setItems(items); TX$4x~:
setStartIndex(startIndex); 3s$vaV~(a
} 9<-7AN}Z
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public PaginationSupport(List items, int Xx
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totalCount, int pageSize, int startIndex){ 6~!l7HqO
setPageSize(pageSize); +$\/HO
setTotalCount(totalCount); noQS bI
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setItems(items); 4ZrRgx2MD
setStartIndex(startIndex); P,={ C6*
} Hm
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publicList getItems(){ uxsi+vkI
return items; M|}V6F_y
} L<[%tv V
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publicvoid setItems(List items){ zL/rV<
this.items = items; (Kb_/
} ECr}7R%
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publicint getPageSize(){ HAdDr!/`
return pageSize; YzeNr*
} ID8u&:
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publicvoid setPageSize(int pageSize){ 2su/I
this.pageSize = pageSize; WADAp\&
} 4)NbQ[
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publicint getTotalCount(){ Vl%UT@D|
return totalCount; (u-eL#@
} ]lZg }7h
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publicvoid setTotalCount(int totalCount){ eR>|1s%^
if(totalCount > 0){ V&Q_iE
this.totalCount = totalCount; nIf~ds&TT
int count = totalCount / ['Y"6[1
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pageSize; 7)dCdO
if(totalCount % pageSize > 0) b;IzK'
count++; J)._&O$
indexes = newint[count]; 0Q!/A5z
for(int i = 0; i < count; i++){ !YENJJ
indexes = pageSize * cN%@
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} g1&>.V}!
}else{ EClx+tz;`
this.totalCount = 0; \x<i6&.
} T*jQzcm~?
} 6}>CPi#
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publicint[] getIndexes(){ \"1%>O*
return indexes; @cu#rWiG
} \/F*JPhy
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publicvoid setIndexes(int[] indexes){ c)4L3W-x=
this.indexes = indexes; ^"] ]rZ)
} yyM`J7]J
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publicint getStartIndex(){ $nr=4'yZ
return startIndex; vC!B}~RG
} ^5rB/y,
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publicvoid setStartIndex(int startIndex){ ~'w]%rh!
if(totalCount <= 0) fxknfgbg
this.startIndex = 0; Q)2i{\GPVn
elseif(startIndex >= totalCount) =buarxk
this.startIndex = indexes #MUY!
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[indexes.length - 1]; K8RV=3MBLD
elseif(startIndex < 0) l-$5CO
this.startIndex = 0; U<I]_]
else{ U88gJ[$
this.startIndex = indexes 3@wio[
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[startIndex / pageSize]; _0"s6D$
} 1'f&
} xq&r|el
1 RVs!;
publicint getNextIndex(){ @K\hgaQ
int nextIndex = getStartIndex() + W<>R;~)
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pageSize; oaG;i51!
if(nextIndex >= totalCount) 5QP`2I_n
return getStartIndex(); 0( q:K6zI}
else )3.=)?XW
return nextIndex; [xo-ZDIoG
} {$Z
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publicint getPreviousIndex(){ SvQ!n4 $
int previousIndex = getStartIndex() - *yYeqm
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pageSize; V-dyeb
if(previousIndex < 0)
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return0; ^ddC a
else eh}|Wd7J
return previousIndex; B*:W`}G]_c
} ?-JW2 E"uT
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} q\xsXM
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pgBIYeY,
抽象业务类 QL:Qzr[
java代码: %OOy90b2
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/** PLq]\y
* Created on 2005-7-12 o)+C4f[G4
*/ g%okYH?
package com.javaeye.common.business; P q1 j
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import java.io.Serializable; /0b7"Kr
import java.util.List; N
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import org.hibernate.Criteria; ^O<@I
import org.hibernate.HibernateException; ki|OowP
import org.hibernate.Session; ^%O$7*
import org.hibernate.criterion.DetachedCriteria; <Ok7-:OxA
import org.hibernate.criterion.Projections; C!Jy;Z=+u
import o1thGttVDg
;
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org.springframework.orm.hibernate3.HibernateCallback; 9Zr6 KA{
import ;H9 W:_ahE
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org.springframework.orm.hibernate3.support.HibernateDaoS >0?ph<h1[q
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upport; GJ:oUi
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import com.javaeye.common.util.PaginationSupport; J;ycAF ~
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public abstract class AbstractManager extends 8X/SNRk6p
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HibernateDaoSupport { =.l>Uw!
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privateboolean cacheQueries = false; JFq<sY!
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privateString queryCacheRegion; lo-VfKvy
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publicvoid setCacheQueries(boolean %~P3t=r
,YRBYK:
cacheQueries){ #Q BW%L
this.cacheQueries = cacheQueries; JsEnhE}]
} WR_B:%W.
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publicvoid setQueryCacheRegion(String EqOhz II^
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queryCacheRegion){ Oj8D+sC{
this.queryCacheRegion = $`P]%I}
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queryCacheRegion; y5 X FJj
} 92~$Qa\S!
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publicvoid save(finalObject entity){ sGE%zCB
getHibernateTemplate().save(entity); n g9_c
} Wu/:ES)C
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publicvoid persist(finalObject entity){ z\YLO%Mm
getHibernateTemplate().save(entity); Mm!;+bM%
} op3a*KG
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publicvoid update(finalObject entity){ QcX&q%*0
getHibernateTemplate().update(entity); v1/Y0
} /#SH`ZK
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publicvoid delete(finalObject entity){ 9A87vs4[
getHibernateTemplate().delete(entity); /S @iF
} R
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publicObject load(finalClass entity, x6ayFq=
5Q: %f
finalSerializable id){ &da:{
return getHibernateTemplate().load 7>F [7_
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(entity, id); ) )t]5Ys%;
} %'VzN3Q5V
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publicObject get(finalClass entity, I9xkqj
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finalSerializable id){ bdEIvf7
return getHibernateTemplate().get rC_saHo>#R
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(entity, id); \ 7IT[<Se
} (iIzoEpb8W
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publicList findAll(finalClass entity){ )`6OSB
return getHibernateTemplate().find("from [.6bxK
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" + entity.getName()); cucT|y
} PDLps[a
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publicList findByNamedQuery(finalString 7 4&{GCL
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namedQuery){ aj=-^iGG
return getHibernateTemplate BkY#wJ'
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().findByNamedQuery(namedQuery); P@%L.y
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} jy_4W!4a
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publicList findByNamedQuery(finalString query, X":2o|R
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finalObject parameter){ GkI{7GD:z
return getHibernateTemplate |?hsMN
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().findByNamedQuery(query, parameter); K@Xj)
} lkC| g%f
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publicList findByNamedQuery(finalString query, Z,"YMUl'
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finalObject[] parameters){ hegH^IN M
return getHibernateTemplate ej1WkaR8
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().findByNamedQuery(query, parameters); 0fK#:6
} (:h&c6'S)b
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publicList find(finalString query){ T0.sL9
return getHibernateTemplate().find e E(+
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(query); t:xTmK&vt
} 8 qZbsZi4
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publicList find(finalString query, finalObject OMd:#cWsQ
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parameter){ MBnxF^c&P
return getHibernateTemplate().find /LtbmV
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(query, parameter); 4W<[& )7
} A
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public PaginationSupport findPageByCriteria .F[5{XV
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(final DetachedCriteria detachedCriteria){ <I 0om(P
return findPageByCriteria E*kZGHA
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5+j):_
} 4 /v[.5
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public PaginationSupport findPageByCriteria .[1@wW&L
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(final DetachedCriteria detachedCriteria, finalint g>`D!n::n
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startIndex){ GiXs`Yt|
return findPageByCriteria "L8Hgwg
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l
(detachedCriteria, PaginationSupport.PAGESIZE, G({VK
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startIndex); .q!i
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} H+@?K6{h
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public PaginationSupport findPageByCriteria /b/ 6*&
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(final DetachedCriteria detachedCriteria, finalint %?F$3YN,
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pageSize, NzN"_o jM
finalint startIndex){ Zv?"1Y< L
return(PaginationSupport) y{~tMpo<
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getHibernateTemplate().execute(new HibernateCallback(){ m9]Ge]
publicObject doInHibernate Rm6i[y&
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(Session session)throws HibernateException { IGab~`c-[
Criteria criteria = DJqJ6 z:'
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detachedCriteria.getExecutableCriteria(session); MmFtG-
int totalCount = #&?}h)Jr'
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((Integer) criteria.setProjection(Projections.rowCount {<#b@=G
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()).uniqueResult()).intValue(); |CQ0{1R1
criteria.setProjection ]86*k%A
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(null); +At0V(
List items = '+'h^
ULs'oT)K;
criteria.setFirstResult(startIndex).setMaxResults 2 OqEyXh
OI3j!L2f
(pageSize).list(); OKk"S_`
PaginationSupport ps = `DM)tm3&m
d#W^S[[
new PaginationSupport(items, totalCount, pageSize, Lf%}\0:
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startIndex); bQ&%6'ck
return ps; pd.unEWwF
} BxZ7Bk
}, true); kpNp}b8']
} tZFpxyF
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public List findAllByCriteria(final 0F%?<:
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DetachedCriteria detachedCriteria){ I7#JT?\}
return(List) getHibernateTemplate d<WNN1f
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().execute(new HibernateCallback(){ 6#\:J0
publicObject doInHibernate 9}tl@
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(Session session)throws HibernateException { C@<gCM j,"
Criteria criteria = A5]yC\*zt
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detachedCriteria.getExecutableCriteria(session); ,)aUp4*
return criteria.list(); koE]\B2A6
} d>Nh<PqH6
}, true); ^&$86-PB/
} Tks"GlE*D
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public int getCountByCriteria(final -lAY*2Jg
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DetachedCriteria detachedCriteria){ 7r.~L
Integer count = (Integer) Ttp%U8-LJR
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getHibernateTemplate().execute(new HibernateCallback(){ c~OvoTF,
publicObject doInHibernate @D `j
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(Session session)throws HibernateException { nV`W0r(f'
Criteria criteria = y9=<q%Kc-
@ `mke4>_
detachedCriteria.getExecutableCriteria(session); e~cg
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return VWzuV&;P
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criteria.setProjection(Projections.rowCount ;18u02z^
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()).uniqueResult(); Ww#!-,*]o
} +Yc@<$4
}, true); wjgF e]
return count.intValue(); G%=
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} (hIo0.
} 9wO2`e )
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用户在web层构造查询条件detachedCriteria,和可选的 PAxR?2m{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ?5,I`9
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PaginationSupport的实例ps。 ~`B]G
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ps.getItems()得到已分页好的结果集 ta
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ps.getIndexes()得到分页索引的数组 In+2~Jw/2!
ps.getTotalCount()得到总结果数 #^$_3AY
ps.getStartIndex()当前分页索引 F2EX7Crj
ps.getNextIndex()下一页索引 >&F:/
ps.getPreviousIndex()上一页索引 XdOntP *a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 OK47Q{.gh
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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
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一下代码重构了。 GMoz$c6n_
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我把原本我的做法也提供出来供大家讨论吧: jc#gn&4C
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首先,为了实现分页查询,我封装了一个Page类: t)~$p#NS
java代码: 9-24c
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/*Created on 2005-4-14*/ ^gR~~t;@
package org.flyware.util.page; \b$Y_
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/** f;Ijl 0d@
* @author Joa YRd`G3J
* >RpMw!NT
*/ k72NXagh
publicclass Page { YNKvR
y|3("&)"S
/** imply if the page has previous page */ *O)i)["
privateboolean hasPrePage; iWW
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/** imply if the page has next page */ g@Y]$ey%A
privateboolean hasNextPage; HnsLYY\
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/** the number of every page */ e+>$4Jq
privateint everyPage; n1PvZ~^3
VRSBf;?
/** the total page number */ *m`x/_y+
privateint totalPage; M
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/** the number of current page */ \0 &$n
privateint currentPage; %5@>
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/** the begin index of the records by the current kr!>rqN5
N3oa!PE
query */ av:%wJUl,$
privateint beginIndex; ld 1[Usaq
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/** The default constructor */ S?VKzVDB.S
public Page(){ 2t>>08T
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} B7oUS}M
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/** construct the page by everyPage @3FQMs4
* @param everyPage LW">9;n
* */ ?wn<F}UH
public Page(int everyPage){ OqmW lN.?
this.everyPage = everyPage; ,6"[vb#*3
} $Q,]2/o6n
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/** The whole constructor */ 5Kk}sxol
public Page(boolean hasPrePage, boolean hasNextPage, N$.ls48a4-
7;]IlR6
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int everyPage, int totalPage, 1(%6X*z
int currentPage, int beginIndex){ #yEkd2Vy{
this.hasPrePage = hasPrePage; 8H8Q
this.hasNextPage = hasNextPage; \]\ h,Y8
this.everyPage = everyPage; K2V?[O#
this.totalPage = totalPage; t? =V<Yd1
this.currentPage = currentPage; 4\uq$.f-
this.beginIndex = beginIndex; ~SsfkM"
} |t;Ktl
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/** nB5^
* @return g9d/nRX&
* Returns the beginIndex. q~*|Wd'&
*/ o? K>ji!
publicint getBeginIndex(){ ]"j%:fr
return beginIndex; w6^TwjjZ$
} (Fq]y5
oU*e=uehj
/** Y ._Om}H
* @param beginIndex -B-HZ_
* The beginIndex to set. C]ax}P>BQ
*/ G%h+KTw
publicvoid setBeginIndex(int beginIndex){ 7; ?7q
this.beginIndex = beginIndex; f3:dn7
} RK)ikLgp
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/** %+UTs'I
* @return ft iAty0n
* Returns the currentPage. ]I;owk,
*/ o_[I#PT
publicint getCurrentPage(){ yBv4 xKMH
return currentPage; NL!xkcXO
} 0TiDQ4}i[
z:)*Aobwv
/** 4FKgp|Y0
* @param currentPage {?X +Yw
* The currentPage to set.
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*/ Z 8GIZ
publicvoid setCurrentPage(int currentPage){ w[EEA_\
this.currentPage = currentPage; n-<`Z NMU
} T ~p>Ed 9
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/** A v;NQt8ut
* @return 1 7iw`@
* Returns the everyPage. Y'R/|:YL@
*/ c^5fhmlt
publicint getEveryPage(){ twa H20
return everyPage; 2&AX_#P
} P;|63"U
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/** {`Mb ),G
* @param everyPage wGHVq
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* The everyPage to set. ^a!oq~ZSy
*/ ?3v-ppw%
publicvoid setEveryPage(int everyPage){ QPvWdjf#mM
this.everyPage = everyPage; S>"C}F$X
} @ W q8AFo
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/** p-7?S^!l
* @return x'%vL",%
* Returns the hasNextPage. X6?Gxf,
*/ yDpv+6(a
publicboolean getHasNextPage(){ t6)R37
return hasNextPage; |;U3pq)
} a<((\c_8G
*;lb<uLv
/** xz7CnW1
* @param hasNextPage F^=y+}]=
* The hasNextPage to set. jo0XOs
*/ /u"Iq8QA
publicvoid setHasNextPage(boolean hasNextPage){ Ie8K[ >
this.hasNextPage = hasNextPage; E!,jTaZz
} x"Ij+~i{l
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/** &G3$q,`H
* @return $u)#-X;x
* Returns the hasPrePage. e)F_zX
*/ KT<N
;[;
publicboolean getHasPrePage(){ ItAC=/(d
return hasPrePage; w7<4D,hk
} GzT?I
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/** o+S?j*mv@
* @param hasPrePage :/}=s5aQl/
* The hasPrePage to set. =knBwjeD
*/ D2\Ep L/
publicvoid setHasPrePage(boolean hasPrePage){ HDs8 M
this.hasPrePage = hasPrePage; q+XU Cnv
} /j\.~=,_
` ^z
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/** of`WP
* @return Returns the totalPage.
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* yv> 6u7
*/ a1v?{vu\E
publicint getTotalPage(){ g{m~TVm'
return totalPage; X(C=O?A
} \Fu(IuD
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/** /T 4GPi\lg
* @param totalPage VB4ir\nF
* The totalPage to set. t & 5s.
*/ h>/L4j*Z
publicvoid setTotalPage(int totalPage){ N,ZmGzNP)
this.totalPage = totalPage; RRGs:h@;
} krXU*64
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} yJ8_<A
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 1Msc:7:L
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个PageUtil,负责对Page对象进行构造: )fc+B_
java代码: hWr}Uui
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/*Created on 2005-4-14*/ asYUb&Hz88
package org.flyware.util.page; _^F%$K6
=jRC4]M})
import org.apache.commons.logging.Log; nA+gqY6 6|
import org.apache.commons.logging.LogFactory; 1]7v3m
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/** ;O({|mpS\
* @author Joa : Z3]Dk;y
* nTz(
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*/ YA8ZB&]En/
publicclass PageUtil { V:1_k"zQ
+3-f$/po
privatestaticfinal Log logger = LogFactory.getLog PkF'#W%
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(PageUtil.class); z*/}rk4i
f5#VU7=1F2
/** %){) /~e&
* Use the origin page to create a new page Gg5>~"pb
* @param page .[vYT.LE
* @param totalRecords Z7dV y8J
* @return 28 ;x5m)N
*/ {
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publicstatic Page createPage(Page page, int D(Q=EdlO
)AAPT7!U
totalRecords){ 6W N(Tw
return createPage(page.getEveryPage(), zUJPINDb
D (">bR)1
page.getCurrentPage(), totalRecords); Jrx]/CM
} }<H0CcG
= /=?l
/** /6#i$\ j
* the basic page utils not including exception 2S-z$Bi}]
b!z=:
handler _RG2I)P
* @param everyPage !JPZ7_nn
* @param currentPage qD5)AdCGO
* @param totalRecords F6
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* @return page ,<=_t{^
*/ +J:wAmY4
publicstatic Page createPage(int everyPage, int z;EDyd,O>
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currentPage, int totalRecords){ ]"U/3dL5
everyPage = getEveryPage(everyPage); -VZ?
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currentPage = getCurrentPage(currentPage); 8?$XT
int beginIndex = getBeginIndex(everyPage, Opf^#6'mq
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currentPage); Vpf7~2[q%
int totalPage = getTotalPage(everyPage, x7c#kU2A&Z
#h2 qrX&+
totalRecords); .&n;S';"
boolean hasNextPage = hasNextPage(currentPage, lAPPng`
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totalPage); ZG_iF#
boolean hasPrePage = hasPrePage(currentPage); r%` |kN
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returnnew Page(hasPrePage, hasNextPage, jGOE
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everyPage, totalPage, 4Kn)5>
currentPage, :&$WWv
)<^G]ajn
beginIndex); gqACIXR
}
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privatestaticint getEveryPage(int everyPage){ h2ou ]
return everyPage == 0 ? 10 : everyPage; + :k"{I
} -|/*S]6kK
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privatestaticint getCurrentPage(int currentPage){ Hc-Ke1+
return currentPage == 0 ? 1 : currentPage; 4Pr@<S"U
} -y)g}D%
OG2&=~hOz-
privatestaticint getBeginIndex(int everyPage, int wXU gxa
LKu
,H
currentPage){ #:}mi;{
return(currentPage - 1) * everyPage; (Z at|R.F
} ;%$wA5"2M
)W3kBDD
privatestaticint getTotalPage(int everyPage, int "l
1z@
C 4hvk'=
totalRecords){ e2MjV8Bs
int totalPage = 0; QhmOO-Z?
Eilo;-El
if(totalRecords % everyPage == 0) }1Km h]
totalPage = totalRecords / everyPage; c$R<j'7
else [knwp$
totalPage = totalRecords / everyPage + 1 ; Ia*T*qJu
-v?)E
S
return totalPage; <~35tOpv
} )r:gDd#/X
?F@X>zR2
privatestaticboolean hasPrePage(int currentPage){ +We=- e7
return currentPage == 1 ? false : true; hquN+eIDH
} M0"}>`1lJ
SI/p8 ^
privatestaticboolean hasNextPage(int currentPage, T+)#Du
9l:vVp7Uk
int totalPage){ K{]\}7+
return currentPage == totalPage || totalPage == 17B`
gYvT'72
0 ? false : true; Mg=R**s1x%
} A>QAR)YP
t[b@P<F
{DbWk>[DkG
} -owap-Va
n_46;lD
!jyy`q=
Rln@9muXA
U&SgB[QHO
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。 P(Q}r7F~(
3"iJ/Hc}9
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 }i@%$Ixsn
&cB+la\_
做法如下:
tf?"AY4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 K8|>" c~
CeW}zkcT
的信息,和一个结果集List: l08JL
java代码: BMovl4*5
nO .:f
K.: :P84m;
/*Created on 2005-6-13*/ 3B[u2o>
package com.adt.bo; r>x>aJ
be:=-B7!
import java.util.List; )dZ1$MC[
3C(V<R?
import org.flyware.util.page.Page; jinXK
.+dego:
/** u4.2u}A/R%
* @author Joa }R2afTn[;
*/ #tlhH\Pr[
publicclass Result { q;H5S<]/
}X^CH2,R
private Page page; O(YvE
s!\Gi5b
private List content; `& }C*i"
vON1\$bu`
/** cK~VNzsz
* The default constructor 3pI)
*/ 299uZz}Y
public Result(){ %n:ymc
$}
super(); pl5Q2zq%
} @rt}z+JF
]{PJ
/** H5?H{
* The constructor using fields \:`-"Ou(*
*
^U0)iz
* @param page L<H6AzR+
* @param content EGJrnz8
*/ m005*>IY
public Result(Page page, List content){ /faP@Q3kR
this.page = page; y`p(}X`>
this.content = content; &U0Y#11Cx
} >J_%'%%f
Gjo&~*;
/** nj5Hls
* @return Returns the content. l\1_v7s
*/ &1,{.:@e
publicList getContent(){ WiCJhVF3
return content; Q'K[?W|C
} (ixlFGvEq
TM^.y
Y
/** +IPMI#n
* @return Returns the page. >`u/#mrd
*/ 5R/k8UZ
public Page getPage(){ (G`O[JF
return page; wQw
y+S
} 6V6,m4e
Q"b62+03
/** |!.VpN&
* @param content bx=9XZ9g
* The content to set. %8~g#Z
*/ mM)d`br
public void setContent(List content){ YKG}4{T
this.content = content; [pYjH+<
} px=r~8M9}
6T ,'Oz
/** d2[R{eNX=
* @param page V{yk
* The page to set. Tl`HFZQ1
*/ u[?M{E/HU
publicvoid setPage(Page page){ mZ}C)&,m2
this.page = page; [V _\SQV0
} +DA,|~k_
} sRDxa5<MD
GP;UuQz
gWpG-RL0
Vf] ;hm
+o^sm '$
2. 编写业务逻辑接口,并实现它(UserManager, {2MS,Ua{
9,G94.da
UserManagerImpl) 31=vUS
java代码: _&|<(m&."
%r >Y)@$Vt
X8212[7
/*Created on 2005-7-15*/ ]d -U
package com.adt.service; `}|$eF&
`as6IMqJD
import net.sf.hibernate.HibernateException; Z}s56{!.
T@x_}a:g
import org.flyware.util.page.Page; <n{-&;>
;LE9w^>^V
import com.adt.bo.Result; >}'WL($5U
W@FRKDixG
/** tB==v{t
* @author Joa `g!NFp9q
*/ Tmr%r'i3
publicinterface UserManager { Cso-WG,
Yi+$g
public Result listUser(Page page)throws z`KP
}-
8bI;xjK^Q
HibernateException; e<1)KqG
+je{%,*
} @]xHt&j
J{h?=vK
@'fWS^ ;&
MZK%IC>
_W^{,*p
java代码: 0;avWa)Q
wwVg'V;
5;_&C=[
/*Created on 2005-7-15*/ !R@s+5P)U
package com.adt.service.impl; 2JX@#vQ4
D~LU3#n
import java.util.List; VSW"/{Lp
Zz@wbhMV
import net.sf.hibernate.HibernateException; bFtzwa5Gc
atmTI`i
import org.flyware.util.page.Page; To@77.'
import org.flyware.util.page.PageUtil; 6BIr{SY
}hA h'*(
import com.adt.bo.Result; 9G=HG={
import com.adt.dao.UserDAO; CWW|?
import com.adt.exception.ObjectNotFoundException; b5.L== >
import com.adt.service.UserManager; F
uJ=]T
/Ym!%11`
/** >P[BwL]
* @author Joa :1,xs e
*/ T
}^2IJ]
publicclass UserManagerImpl implements UserManager { TU}./b@F
8PtX@s43\
private UserDAO userDAO; BFH=cs
tX7TP(
/** _l||69|.
* @param userDAO The userDAO to set. 0D:e P``
*/ L qdzqq
publicvoid setUserDAO(UserDAO userDAO){ WuUT>omH
this.userDAO = userDAO; sad[(|
} :Co+haW
)3A%Un#B
/* (non-Javadoc) 6 Z7J<0
* @see com.adt.service.UserManager#listUser VH2/
=]<JkWSk
(org.flyware.util.page.Page) L$4nbOu\~
*/ m0_B[dw
public Result listUser(Page page)throws 3P[u>xE
cu#s}*Ip
HibernateException, ObjectNotFoundException { Ye"#tCOEG
int totalRecords = userDAO.getUserCount(); 71inHg
if(totalRecords == 0) "R9^X3;
throw new ObjectNotFoundException {u_2L_
19#A7
("userNotExist"); XbMAcgS
page = PageUtil.createPage(page, totalRecords); 8@J5tFJ&%
List users = userDAO.getUserByPage(page); l5fF.A7TT
returnnew Result(page, users); nk^-+olm
} bdz&"\$X
~u+|NtF
} ^#)M,.G^
EaXDY<
ug.'OR
|{JJ2c\W
5X=ik7m^
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @#W$7Gwf0
+KKx\m*
询,接下来编写UserDAO的代码: M+Jcgb]
3. UserDAO 和 UserDAOImpl: 9&p;2/H
java代码: ~s UWXw7~
T_1p1Sg
gg}^@h&?
/*Created on 2005-7-15*/ {_<,5)c
package com.adt.dao; }$T!qMst{
?~#{3b
import java.util.List; `UH 1B/
X"p p l7o
import org.flyware.util.page.Page; P|{Et=R`1
`p{,C`g,R
import net.sf.hibernate.HibernateException; N>3X! K
6A \Z221E
/** Isna
KcLM
* @author Joa AiE\PMF~{P
*/ s#2<^6
publicinterface UserDAO extends BaseDAO { \~ql_X;3
4bZ
+nQgLu
publicList getUserByName(String name)throws .e8S^lSl
xPJ
kadu
HibernateException; P<GHX~nB
%*`yd.L0W
publicint getUserCount()throws HibernateException; %V&I${z
Vj{}cL"MR
publicList getUserByPage(Page page)throws 9}DF*np`G
LwL\CE_6+
HibernateException; 0nOp'Ky\k
TSCc=c
} u{"@
4
rGxX]
>W[#-jA_Z
sB>ZN3ptH^
YMEI
J}
java代码: ,H+LE$=
Z6XP ..
^&-H"jF
/*Created on 2005-7-15*/ ZFsJeF'"
package com.adt.dao.impl; Q0cr^24/
u]%>=N(^2
import java.util.List; q|fZdTw
!NfN16
import org.flyware.util.page.Page; Rf.b_Y@O
[6Nw)r(a(
import net.sf.hibernate.HibernateException; m&X6a C'[
import net.sf.hibernate.Query; oI6o$C
gQ=g,X4
import com.adt.dao.UserDAO; FTfejk!
U%,N"]`
/** o)hQ]d
* @author Joa 2AZ)|dM'`
*/ G,J~Ed
public class UserDAOImpl extends BaseDAOHibernateImpl zrJ/Fs+s
|vY0[#E8&
implements UserDAO { s*0PJ\E2
}|7y.*
/* (non-Javadoc) i`2X[kc
* @see com.adt.dao.UserDAO#getUserByName |,wp@)e6h
vHz]-Q-|9
(java.lang.String) m+m,0Ey5H
*/ 8Qg,UX
publicList getUserByName(String name)throws )|@ H#kv?
[# '38
HibernateException { 0u'qu2mV
String querySentence = "FROM user in class +Eh^j3W
T]fu[yRVvg
com.adt.po.User WHERE user.name=:name"; Cp@'
k;(
Query query = getSession().createQuery ?]#U~M<'
Aj;F$(su
(querySentence); G`HL^/Z*
query.setParameter("name", name); bqt*d)$
return query.list(); tsA+B&R_]
} VYZkHjj)2i
#+-
/0{HT
/* (non-Javadoc) Aey*n=V4#F
* @see com.adt.dao.UserDAO#getUserCount() ZAG iaq
*/ #*<*|AwoW|
publicint getUserCount()throws HibernateException { 6SIk,Isy8
int count = 0; d:"]*EZ [
String querySentence = "SELECT count(*) FROM $`emP
Hel
<+QX Gz1
user in class com.adt.po.User"; T&] J3TFJ
Query query = getSession().createQuery x{X(Y]*1S
xD(JkOne
(querySentence); .kO;9z\B
count = ((Integer)query.iterate().next ~Zc=FP:1
9p#Laei].
()).intValue(); =nYd|Ok
return count; '$3]U5KOwK
} +hIStA
YYz,sR'%|}
/* (non-Javadoc) w<hw>e^.
* @see com.adt.dao.UserDAO#getUserByPage KKd Sh1
)-_]y|/D:r
(org.flyware.util.page.Page) 7X$[E*kd
*/ E-\<,=bh
publicList getUserByPage(Page page)throws oT4A|M
fq.ui3lP)
HibernateException { ]i-peBxw
String querySentence = "FROM user in class `;ofQz4
rSUarfZ<
com.adt.po.User"; GN4'LU
Query query = getSession().createQuery G 1rsd
N;9m&)@JR'
(querySentence); 93-UA.+g
query.setFirstResult(page.getBeginIndex()) ) /kf
.setMaxResults(page.getEveryPage()); * ?a-m\
return query.list(); G $TLWfm
} .X;zEyd
mZ^z%+Ca|
} MqBA?7
!TH3oLd"
+P?!yH,n
>[=fbL@N<@
gNdEPaaFI
至此,一个完整的分页程序完成。前台的只需要调用 2FxrMCC
UJXRL
userManager.listUser(page)即可得到一个Page对象和结果集对象 p9;Oe,Il
=rA "|=
的综合体,而传入的参数page对象则可以由前台传入,如果用 Tl^9!>\Q
@O/Jy2>3H
webwork,甚至可以直接在配置文件中指定。 =kz(1Pb
"F(LTppy
下面给出一个webwork调用示例: BULf@8~(
java代码: 9+G.86Iky
k !S0-/h
<n4T*
/*Created on 2005-6-17*/ S`oADy
package com.adt.action.user; 3[g%T2&[
S <C'#vj
import java.util.List; )uvs%hK
[*<F
import org.apache.commons.logging.Log; "lcNjyU\O
import org.apache.commons.logging.LogFactory; ZqhCGHy
import org.flyware.util.page.Page; uES|jU{]b
*OOi
import com.adt.bo.Result; +/tNd2
import com.adt.service.UserService; |gvx^)ro
import com.opensymphony.xwork.Action; $^Is|]^
wN"j:G(
/** )~{T
* @author Joa QxRT%;'Zh]
*/ R36BvW0X
publicclass ListUser implementsAction{ :}\w2W E[
?v4-<ewD
privatestaticfinal Log logger = LogFactory.getLog ~s@PP'!
l^ P[nQDH
(ListUser.class); "<3F[[;~
:a M
ZJm
private UserService userService; *f% u c
^gb3DNV~y
private Page page; G_GV
'c[[H3s!;
privateList users; <l/QS3M
{sn RS)-
/* Z)?i&y?
* (non-Javadoc) e>zCzKK
* EZy:_xjZ
* @see com.opensymphony.xwork.Action#execute() 'Vwsbm
tY
*/ Zj@k3y
publicString execute()throwsException{ KMO(f!?
Result result = userService.listUser(page); n[~kcF
page = result.getPage(); `nAR/Ye
users = result.getContent(); ;JM%O8
return SUCCESS; D00I!D16
} B?BB
>K
}j}M%
/** 00Tm]mMQX
* @return Returns the page. kvWP[! j?)
*/ k3F*D
public Page getPage(){ Y$3 &?LA
return page; r5U[jwP
} .<0|V
|'$E-[
/** a$0,T_wD
* @return Returns the users. Gwyjie 9t
*/ PtH>I,/
publicList getUsers(){ Gk<M@d^hQ
return users; bXSsN\:Y@[
} |m x)W}
[1+ o
/** !GB\-(
* @param page >
-P UY
* The page to set. 0rM'VgB
*/ 8|Wu8z--
publicvoid setPage(Page page){ d']CBoK
this.page = page; 7R4sd
} :{:R5d(_I
lD`@{A
/** 5)tDgm
* @param users >3{#S:
* The users to set. I4[sf
*/ ]q#w97BxiJ
publicvoid setUsers(List users){ 1(S0hm[ov
this.users = users; W9i}w&
} %2H0JXKa,
h(M_
K
/** ^^q9+0@
* @param userService I-?PTr
* The userService to set. 0\qLuF[)
*/ Z7\}x"hk
publicvoid setUserService(UserService userService){ fN)A`> iP
this.userService = userService; ]H ze
} Sz!mn
} N*J!<vY"
vBFMne1h
y
{&"g
(R'GrN>
mEL<d,XhI
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, }>q%##<n
Uq}F rK}
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 #6fQ$x(F#j
41-u*$
么只需要: NOC8h\s}(
java代码: rM?O 2n
v'0WE
9' $\GN{0
<?xml version="1.0"?> QcW6o,
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork , %8keGhl
c(@(j8@S
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _wp>AJ r
xqZZ(jZ
1.0.dtd"> }PC_qQF
[-ONs
<xwork> 2p^Jqp`$
/Bt+Ov3k
<package name="user" extends="webwork- )Y@E5Tuk>
r6JQRSakR
interceptors"> m`;dFL7"E
(]_smsok
<!-- The default interceptor stack name ^bD)Tg5K
*Z9Rl>
--> N7Kg52|
<default-interceptor-ref /$EX-!ie
$,b1`*
name="myDefaultWebStack"/> -0I]Sm;$
Rcn6puZt
<action name="listUser" g6 AEMer
PZ#\O
class="com.adt.action.user.ListUser"> +#;t.&\80N
<param Z=[qaJ{]
VnjhEEM!
name="page.everyPage">10</param> k},@2#W]
<result QPD[uJ(I
`6No6.\J
name="success">/user/user_list.jsp</result> _nUvDdEs,
</action> [Sj _=
8I>'xf
</package> 5WlBec@
%%-?~rjI
</xwork> qsA`\%]H
S9
p*rk~
' ?4\
$D][_ I
ydZS^BqG
iQT$#"m
n
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 T^Lg+g+I
>~F_/Z'5
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。 &.v|yG]&
5~R1KjjvA
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 _c z$w5`
gN/kNck
IYG,nt!
(kY wD
J<9;Ix8R
我写的一个用于分页的类,用了泛型了,hoho ov
'g'1}
)yTBtYw3
java代码: GG=R!+p2
4[XiD*
*
LykB2]T
package com.intokr.util; r\j*?m ]
w/oXFs&FK
import java.util.List; 7l+:gD
FJ+n-
\
/** VF bso3q<j
* 用于分页的类<br> 2(i@\dZCb<
* 可以用于传递查询的结果也可以用于传送查询的参数<br> h,fC-+H5
* XU*4MU^'
* @version 0.01 eZ
G#op
* @author cheng ?qmJJ5Gn
*/ w(N$$
public class Paginator<E> { :z^,>So :
privateint count = 0; // 总记录数 1sIPhOIys
privateint p = 1; // 页编号 }m -A #4.
privateint num = 20; // 每页的记录数 Lz/{
q6>
privateList<E> results = null; // 结果 9F"^MzZ
xTGdh
/** t_"]n*zk1
* 结果总数 L;
o$vI~U,
*/ 1$S`>M%a
publicint getCount(){ U)JwoO
return count; H/^t]bg,
} sK/Z'h{|
@Rw]boC
publicvoid setCount(int count){ yEPkF0?
this.count = count; L!LhH
} K})w
-Q MO*PY
/** GlOSCJZ
* 本结果所在的页码,从1开始 bjr()NM1
* gWGh:.*T
* @return Returns the pageNo. W @]t
*/ jr2wK?LbB
publicint getP(){ Fzk%eHG=
return p; V6!1(|
} PLueH/gC .
.jv#<"DW
/** K9tr Iy$v
* if(p<=0) p=1 VUUE2k;^
* o^3X5})sv
* @param p 0x2[*pJ|IW
*/ 1EHL8@.M
publicvoid setP(int p){ 7?p>v34A
if(p <= 0) Vv_lBYV
p = 1; V$fn$=
this.p = p; Fql|0Fq
} `9&~fWu
J,D^fVIw
/** QIC? `hk1
* 每页记录数量 |0nt u+
*/ c2Yrg@) [
publicint getNum(){ $)Ty@@7C
return num; yfZYGhPN(
} miB+'n"zS
fo_*Uva_
/** o#QS: '|
* if(num<1) num=1 !-~sxa280r
*/ y41~
publicvoid setNum(int num){ A(D3wctdr
if(num < 1) NRMEZ\*L
num = 1; !%(PN3*
this.num = num; Ya29t98Pk
} sI5S)^'IQ
0gsRBy
/** .c]@xoC
* 获得总页数 I\<)9`O
*/ kLe{3>}j
publicint getPageNum(){ 6^sH3=#
return(count - 1) / num + 1; xs^wRE_
} <"@5. f1"Y
G<>h>c1>z
/** 6$&%z Eh
* 获得本页的开始编号,为 (p-1)*num+1 -u^f;4|u
*/ OV/
&'rC
publicint getStart(){ H+5S )r
return(p - 1) * num + 1; 4O7
{a
} \ch4c9
dYZB>
OS
/** .s%dP.P:i1
* @return Returns the results. ~BC~^D&WD
*/ 8|~ M!<
publicList<E> getResults(){ l9naqb:iP
return results; M:t"is
} er.;qV'Wz6
Q#lFt,.y
public void setResults(List<E> results){
tPChVnB
this.results = results; `B/74Wa3q
} 3'!*/UnU
N6BEl55 &
public String toString(){ vu~7Z;y(<j
StringBuilder buff = new StringBuilder ot,=.%O
nq:'jdY5|
(); eQJyO9$G
buff.append("{"); \u*[mrX_B:
buff.append("count:").append(count); F- {hXM
buff.append(",p:").append(p); D22A)0+_
buff.append(",nump:").append(num);
o('6,D
buff.append(",results:").append df{6!}/(
;v5Jps2^]
(results); >"[Nmx0;w
buff.append("}"); \xKhbpO~
return buff.toString(); ->'xjD
} '[p0+5*x
\t]_UNGyW
} x$) E^|A+
tja7y"(]
bO+e?&vQ%