Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 =i~/.Nu&
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 5m&{f>]T
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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 o^wj_#ai$
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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 - o$S=
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分页支持类: k2sb#]-/}
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java代码: )zlksF
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package com.javaeye.common.util; j9XY%4.
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import java.util.List; ,miU'<8tQ|
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publicclass PaginationSupport { oOy@X =cw
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publicfinalstaticint PAGESIZE = 30; )fP,F(
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privateint pageSize = PAGESIZE; R!lNm,i
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privateList items; lSC3m=4g
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privateint totalCount; UTc$zc7
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privateint[] indexes = newint[0]; ndT:,"s
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privateint startIndex = 0;
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public PaginationSupport(List items, int SE)_5|k*
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totalCount){ { cnya*
setPageSize(PAGESIZE); 38b%km#
setTotalCount(totalCount); 2/sD#vC
setItems(items); Bs =V-0
setStartIndex(0); m=Y9s B
} c!T^JZBb
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public PaginationSupport(List items, int 73P=<3
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totalCount, int startIndex){ PvBx<i}A
setPageSize(PAGESIZE); cEnkt=
setTotalCount(totalCount); P5* :r3>
setItems(items); ,RKBGOz?f
setStartIndex(startIndex); I7r{&X) D
} YR'?fr
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public PaginationSupport(List items, int 9*GwW&M%1_
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totalCount, int pageSize, int startIndex){ 5Qd |R
setPageSize(pageSize); 5)'
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setTotalCount(totalCount); x=Qy{eIe
setItems(items); f)H6 nl7r
setStartIndex(startIndex); ~mOGNf?f
} 8 Mp2MZ*p
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publicList getItems(){ 8[Cp
return items; 25BW/23}e
} ^_9 ^iL
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publicvoid setItems(List items){ NoO>CjeFb
this.items = items; l
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} iC?s`c0B
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publicint getPageSize(){ q#LwM]<.@>
return pageSize; 7s;<5xc
} D$q"k"
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publicvoid setPageSize(int pageSize){ #QXv[%k
this.pageSize = pageSize; Wg[?i C*~
} pRx^O
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publicint getTotalCount(){ gn1`ZYg
return totalCount; O_K@\<;~
} {R
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publicvoid setTotalCount(int totalCount){ 4A^hP![c#]
if(totalCount > 0){ 7{RI`Er`
this.totalCount = totalCount; Ev0GAc1
int count = totalCount / !H{)L@f
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pageSize; fKOm\R47
if(totalCount % pageSize > 0) gGw6c" FRQ
count++; H$KE*Wwq
indexes = newint[count]; Fx4C]S
for(int i = 0; i < count; i++){ DBAJkBs
indexes = pageSize * VH4P|w[YF
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i; /O|!Sg{
} 'G>Ejh@t
}else{ x5v^@_:
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this.totalCount = 0; *h1Zqb
} WGN[`D"
} pu=T
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publicint[] getIndexes(){ Odxq ]HlbO
return indexes; x,E#+
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} 0t}=F4@&a
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publicvoid setIndexes(int[] indexes){ _55T
this.indexes = indexes; ,r{*o6
} 4U<'3~RN
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publicint getStartIndex(){ m}:";>?#
return startIndex; 2n?\tOm(V
} &~pj)\_
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publicvoid setStartIndex(int startIndex){ 6T< ~mn
if(totalCount <= 0) @pQv}%
this.startIndex = 0; HQ7-,!XO
elseif(startIndex >= totalCount) vF;6Y(h>
this.startIndex = indexes PtO-%I<N
' :g8a=L
[indexes.length - 1]; UYW%%5p?
elseif(startIndex < 0) v!t*Ng
this.startIndex = 0; |o~FKy1'z\
else{ (sS[F-2R7
this.startIndex = indexes \cPGyeq
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[startIndex / pageSize]; Y((z9-`
} *u>2" !+Ob
} eG|e1t K+
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publicint getNextIndex(){ _E)xR
int nextIndex = getStartIndex() + \9Itu(<f
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pageSize; VPys
if(nextIndex >= totalCount) ZgtW
return getStartIndex(); 4@5rR~DQq
else wz.Il-sm
return nextIndex; ]O<Yr'
} ]SBv3Q0D7
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publicint getPreviousIndex(){ NTXT0:
int previousIndex = getStartIndex() - ;&WN%L*
{
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pageSize; Xu3^tH-b<
if(previousIndex < 0) _M:)x0("
return0; dLD"Cx
else aZ=WK4
return previousIndex; 1)#<nk)I
} ~IE:i-Kz
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} 1kio.9NIp
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抽象业务类 VOG DD@
java代码: mt fDl;/D
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/** jA=uK6m
* Created on 2005-7-12 GuM-H$,
*/ xVfJ]Y
package com.javaeye.common.business; uAzVa!)
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import java.io.Serializable; J9/9k
import java.util.List; s]L`&fY]O
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import org.hibernate.Criteria; }-zx4<4BH
import org.hibernate.HibernateException; YH':cze
import org.hibernate.Session; 3(^9K2.s}
import org.hibernate.criterion.DetachedCriteria; +;Cq>1x,
import org.hibernate.criterion.Projections; &HFMF)NA
import Ng'f u|
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org.springframework.orm.hibernate3.HibernateCallback; WRVKh
import Fj 1/B0acS
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org.springframework.orm.hibernate3.support.HibernateDaoS ,>{4*PM(
X?>S24I"9
upport; tjDVU7um
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import com.javaeye.common.util.PaginationSupport; }5Y.N7F
&`@,mUi{Ac
public abstract class AbstractManager extends !!2~lG<]
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HibernateDaoSupport { EoQ.d|:g
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privateboolean cacheQueries = false; ^Xa-)Pu
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privateString queryCacheRegion; U%gP2]t%cs
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publicvoid setCacheQueries(boolean WgE~H)_%
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cacheQueries){ 2Q9s?C
this.cacheQueries = cacheQueries; He#+zE;
} _<t3~{qUT
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publicvoid setQueryCacheRegion(String H@G7oK
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queryCacheRegion){ T]CvfvO5
this.queryCacheRegion = @|-ydm0
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queryCacheRegion; 3XL0Pm
} QR4v6*VpD
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publicvoid save(finalObject entity){ wfo}TGhC
getHibernateTemplate().save(entity); lJ7k4ua\
} ? ~_%I
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publicvoid persist(finalObject entity){ ReSP)%oW
getHibernateTemplate().save(entity); k9}im
} }E?s*iP
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publicvoid update(finalObject entity){ ? _HTOOa
getHibernateTemplate().update(entity); !o*oT}6n
} j:<E=[Kl
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publicvoid delete(finalObject entity){ %#7M~RB[
getHibernateTemplate().delete(entity); 1ed#nB%
} yD(/y"P,9
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publicObject load(finalClass entity, -MB,]m
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finalSerializable id){ |2n2
return getHibernateTemplate().load {_k 6 t
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(entity, id); /eIwv31
} nHZ 4):`
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publicObject get(finalClass entity, h!d#=.R
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finalSerializable id){ 0CTI=<;
return getHibernateTemplate().get DCwldkdJN
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(entity, id); u=ENf1{ $>
} o
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publicList findAll(finalClass entity){ [fO]oTh
return getHibernateTemplate().find("from W>B:W 0A
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" + entity.getName()); s[xdID^3.
} =faV,o&{`
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publicList findByNamedQuery(finalString iT.hXzPzr*
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namedQuery){ N4H nW0
return getHibernateTemplate =3 -G
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().findByNamedQuery(namedQuery); w7dG=a&
} V]vk9M2q[l
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publicList findByNamedQuery(finalString query, 4AP<mo
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finalObject parameter){ r-'j#|^tz
return getHibernateTemplate R \`,Q'3
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().findByNamedQuery(query, parameter); :j9;P7&"?
} [=LQ,e$r7
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publicList findByNamedQuery(finalString query, JNMZn/
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finalObject[] parameters){ t3bN
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return getHibernateTemplate Xq J@NgsY
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().findByNamedQuery(query, parameters); ["@K~my~D*
} lHP[WO
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publicList find(finalString query){ 1h)I&T"kZ
return getHibernateTemplate().find ,Zs-<e"
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(query); C:P, q6
} \ u5%+GA-:
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publicList find(finalString query, finalObject bLf }U9
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parameter){ M4')gG;
return getHibernateTemplate().find ;itz`9T
qU=$ 0M
(query, parameter); hg\$>W~2
} M+nz~,![
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public PaginationSupport findPageByCriteria -y$|EOi?
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(final DetachedCriteria detachedCriteria){ @-u/('vpB
return findPageByCriteria K3\U'bRO
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %X#Wc:b
} &4BN9`|:
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public PaginationSupport findPageByCriteria 'f5,%e2#
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(final DetachedCriteria detachedCriteria, finalint [QL)6Xr
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startIndex){ \UN7lDH
return findPageByCriteria c()F%e:n
b`%/*
(detachedCriteria, PaginationSupport.PAGESIZE, f+gyJ#R`
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startIndex); .\1XR
} #<!oA1MH4
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public PaginationSupport findPageByCriteria t|%iW%m4
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(final DetachedCriteria detachedCriteria, finalint r$.ek\D5
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pageSize, v( (fRX.`
finalint startIndex){ *4+;Ey
return(PaginationSupport) !@ bN
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getHibernateTemplate().execute(new HibernateCallback(){ m:
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publicObject doInHibernate 6' ?Y]K
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(Session session)throws HibernateException { #PtV=Ee1
Criteria criteria = =u73AM}
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detachedCriteria.getExecutableCriteria(session); 5z#>>|1>#
int totalCount = -*tP_=- Dg
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((Integer) criteria.setProjection(Projections.rowCount a"hlPJlG
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()).uniqueResult()).intValue(); &a-:ZA@
criteria.setProjection mJWl#3
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(null); &AlVJEI+
List items = ,D~C40f
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criteria.setFirstResult(startIndex).setMaxResults XlB`Z81j
kGX`y.-[
(pageSize).list(); O7q-MeMM
PaginationSupport ps = tS`fG;
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new PaginationSupport(items, totalCount, pageSize, '<8ewU
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startIndex); ly6?jVJ
return ps; b~v
} ,R*ru*
}, true); .qF@
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} xOD;pRZQ
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public List findAllByCriteria(final /[_>U{~P#
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DetachedCriteria detachedCriteria){ `EV[uj&1S
return(List) getHibernateTemplate Yc\;`C
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().execute(new HibernateCallback(){ 8ae]tX5$
publicObject doInHibernate q6/ o.j
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(Session session)throws HibernateException { ?u 9)
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Criteria criteria = t</Kel|D
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detachedCriteria.getExecutableCriteria(session); 'du:Bxl`d4
return criteria.list(); (q3(bH~T)
} I)DLnnQQ
}, true); j3z&0sc2(0
} Z\O ,9
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public int getCountByCriteria(final T4qbyui{
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DetachedCriteria detachedCriteria){ [#uX{!q'
Integer count = (Integer) D='/-3f!F]
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getHibernateTemplate().execute(new HibernateCallback(){ Wc03Sv&FZ
publicObject doInHibernate 0>Ecm#
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(Session session)throws HibernateException { Alh%Z\
Criteria criteria = WynHcxC
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detachedCriteria.getExecutableCriteria(session); JTl
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return `h :&H,N
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criteria.setProjection(Projections.rowCount 0Q%'vBX\`
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()).uniqueResult(); ZXHG2@E)
} j:$2,?|5
}, true); fd*=`+P
return count.intValue(); -Qqb/y
} OsvAm'B
} Y( D d7`c
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用户在web层构造查询条件detachedCriteria,和可选的 "t`r_Aw
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 u.8vXc
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PaginationSupport的实例ps。 k`2 K?9\
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ps.getItems()得到已分页好的结果集 Lg_y1Mu7o
ps.getIndexes()得到分页索引的数组 9?bfZF4A=
ps.getTotalCount()得到总结果数 BalOph4M[
ps.getStartIndex()当前分页索引 ?i)-K?4Sb
ps.getNextIndex()下一页索引 BxO2w1G
ps.getPreviousIndex()上一页索引 u\&oiwSIP
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错
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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 cV)fe`Gg
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一下代码重构了。 ]Fl+^aLS
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我把原本我的做法也提供出来供大家讨论吧: j\!zz
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首先,为了实现分页查询,我封装了一个Page类: VXR.2C
java代码: ^*%p]r
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/*Created on 2005-4-14*/ A{mbL2AxwC
package org.flyware.util.page; $//18+T
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/** ^7F!>!9Ca
* @author Joa fcD$km
* u%VO'}Gz
*/ f![x7D$
publicclass Page { \*!g0C8 o
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/** imply if the page has previous page */ p^ 9QYR
privateboolean hasPrePage; JR'Q Th:z
\TC&/'7}
/** imply if the page has next page */ XV).
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privateboolean hasNextPage; (3{'GX2c
=u${2=
/** the number of every page */ #e+%;5\
privateint everyPage; &Mo=V4i>
d7$H})[^
/** the total page number */ T*-*U/
privateint totalPage; @\u)k
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/** the number of current page */ @Eqc&v!O
privateint currentPage; /=,^fCCN
roj/GZAy"
/** the begin index of the records by the current <MA!?7Z|
(RWZ[-;)
query */ V*U"OJ%
privateint beginIndex; DtXXfp@;
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/** The default constructor */ =h5&\4r=
public Page(){ $-M1<?5
nU)}!` E
} gC<\1AIu
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/** construct the page by everyPage 6(DK\58
* @param everyPage DY~~pi~
* */ {BY`Wu:w
public Page(int everyPage){ 2s?j5 Sd
this.everyPage = everyPage; @bfaAh~
} tvf"w`H
"&Q-'L!M'/
/** The whole constructor */ N!9DZEcm
public Page(boolean hasPrePage, boolean hasNextPage, ^dYFFKQ
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int everyPage, int totalPage, C&zgt
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int currentPage, int beginIndex){ z})H$]: $
this.hasPrePage = hasPrePage; 1g2%f9G
this.hasNextPage = hasNextPage; 7&'^H8V
this.everyPage = everyPage; @hQ+pG@s
this.totalPage = totalPage; q+WO nTS
this.currentPage = currentPage; j3Cp o
x
this.beginIndex = beginIndex; Z9~~vf#
} E
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/** *~prI1e(
* @return hk}M'
* Returns the beginIndex. H8Pil H
*/ rAn''X6H
publicint getBeginIndex(){ r_FW)F u^
return beginIndex; 9]1-J5iO
} rTDx|pvYx
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/** 7bQ#M )}
* @param beginIndex V6BCW;
* The beginIndex to set. j
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*/ N#Qby4w >
publicvoid setBeginIndex(int beginIndex){ , $78\B^
this.beginIndex = beginIndex; YAC=V?U-#
} xO"5bj
tG^Oj:
/** Ds&)0Iwf
* @return HEht^/pJ
* Returns the currentPage. Fm*n>^P@Y
*/ 7:mM`0g!
publicint getCurrentPage(){ ib/&8)Y+J
return currentPage; 5p
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} O0WzDD
wvx
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/** &>i+2c~
* @param currentPage {LR?#.
* The currentPage to set. L
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*/ NZi5rXN
publicvoid setCurrentPage(int currentPage){ - FA#hUK$
this.currentPage = currentPage; qB<D'h7
} WTY{sq\'
o
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/** +]`MdOu
* @return _BHb0zeot
* Returns the everyPage. 9.#\GI ;
*/ ;=F^G?p^
publicint getEveryPage(){ Pt";f
return everyPage; 7KuTC%7
} '#u|RsZ
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/** y9Yh%M(
* @param everyPage N$:[`,
* The everyPage to set. Z^>3}\_v
*/ wH{lp/
publicvoid setEveryPage(int everyPage){ c 6E@+xU
this.everyPage = everyPage; JgYaA*1X
} <y-KWWE
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/** ldI;DoE#U1
* @return G?'L1g[lc
* Returns the hasNextPage. }4A+J"M4y
*/ m`4Sp#m
publicboolean getHasNextPage(){ rguC#Xt!4
return hasNextPage; #x':qBv#
} -.ha\ t0J
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/** j9x}D;?n
* @param hasNextPage 5c3)p^]g
* The hasNextPage to set. C1r]kF
*/ v(h
publicvoid setHasNextPage(boolean hasNextPage){ *oZBv4Vh
this.hasNextPage = hasNextPage; _d %H;<_
} lwQI
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/** %CD}A%~
* @return vxk1RL*Xu
* Returns the hasPrePage. WP2|0ib
*/ (!W:-|[K\
publicboolean getHasPrePage(){ Co[ rhs
return hasPrePage; B07(15y]
} gqyQ Zew
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/** 0)yvyQ5
* @param hasPrePage nd'zO#"m?
* The hasPrePage to set. Vyu 0OiGcR
*/ M:Xswwq
publicvoid setHasPrePage(boolean hasPrePage){ iN<&
this.hasPrePage = hasPrePage; pRPz1J$58
} g[q1P:I@W
D!TS/J1S;u
/** gSL$silc
* @return Returns the totalPage. :&&Ps4\Sq
*
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*/ T$0//7$')
publicint getTotalPage(){ ,]y)Dy
return totalPage; 0rsdDME[
} T AwA)Zg
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/** T&w3IKb|}
* @param totalPage 4F)z-<-b
* The totalPage to set. d]0fgwwGC
*/ az?B'|VX
publicvoid setTotalPage(int totalPage){ QVb@/
this.totalPage = totalPage; 6EGh8H f
} zw7=:<z=
Z[ZqQ` 7N
} ~BD VmQa
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Beiz*2-}a
jxZR%D
b@/z^k{%
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 ?VCb@&*
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个PageUtil,负责对Page对象进行构造: R1{"
java代码: sn}U4=u
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/*Created on 2005-4-14*/ j42U|CuK
package org.flyware.util.page; ) e;)9~
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import org.apache.commons.logging.Log; ^ :6v-
Yx
import org.apache.commons.logging.LogFactory; Yvs9)g
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/** _;G"{e.=
* @author Joa <,`=m|z9k
* R1&(VK{
*/ iNT 1lk
publicclass PageUtil { IT'~.!o7/
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privatestaticfinal Log logger = LogFactory.getLog %a{cJ6P
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(PageUtil.class); e7{3:y|]d3
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/** M$FQoRwH
* Use the origin page to create a new page 5A>W;Q\4
* @param page "m3u}!`3
* @param totalRecords Y"K7$+5#\
* @return dSS_^E[{
*/ `Ft.Rwj2:m
publicstatic Page createPage(Page page, int u;F++$=
&g\D-At
totalRecords){ =L#tSa=M"
return createPage(page.getEveryPage(), <DvpqlT
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page.getCurrentPage(), totalRecords); )67Kd]
} BBnj}XP*4
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/** "qu%$L
* the basic page utils not including exception : N> 5{
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handler I'`Q_5s5
* @param everyPage d-#MRl$rtK
* @param currentPage s4@AK48
* @param totalRecords :\4?{,@_h
* @return page V#ZF0a]
*/ zEl@jK,{$
publicstatic Page createPage(int everyPage, int (=j]fnH?
8;5 UO,`T
currentPage, int totalRecords){ ullq}}
everyPage = getEveryPage(everyPage); =SRp
currentPage = getCurrentPage(currentPage); Vv
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int beginIndex = getBeginIndex(everyPage, fM]zD/ g
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currentPage); B;SYO>.W
int totalPage = getTotalPage(everyPage, PxM]3Aoa
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totalRecords); LrX7WI
boolean hasNextPage = hasNextPage(currentPage, %A,4vLe~6
9mEC|(m*WK
totalPage); |p4F^!9
boolean hasPrePage = hasPrePage(currentPage); 17a'C
8*V3g_z
returnnew Page(hasPrePage, hasNextPage, :5L9tNr{_
everyPage, totalPage, NJ/6_e
currentPage, R Q X
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54
beginIndex); |dsd5Vdr
} 5sao+dZ"|
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privatestaticint getEveryPage(int everyPage){ ZL:nohB
return everyPage == 0 ? 10 : everyPage; _bHmcK
} JpvE c!cli
%4Y/-xF}9,
privatestaticint getCurrentPage(int currentPage){ j="{^b
return currentPage == 0 ? 1 : currentPage; Hq?-e?Nc
} z:u e]7(.
nr
Jl>H
privatestaticint getBeginIndex(int everyPage, int WtN o@e'
;dPyhR
currentPage){ 7{
(t_N>
return(currentPage - 1) * everyPage; ,P3nZ
} u}W R1u[
9KN75<n
privatestaticint getTotalPage(int everyPage, int 1mz;4xb
ZZL.&Ho
totalRecords){ 4GH?$p|LX
int totalPage = 0; 8{Bcl5]<
Z!0D97^
if(totalRecords % everyPage == 0) @MWrUx
totalPage = totalRecords / everyPage; Y,RBTH
else I dgha9K
totalPage = totalRecords / everyPage + 1 ; [8EzyB>fH
P3jDx{F
return totalPage; 4yW9}=N!
} f
wWI2"}
`PXSQf
privatestaticboolean hasPrePage(int currentPage){ f}PT3
return currentPage == 1 ? false : true; ng(STvSh:
} .S>:-j'u
1@JAY!yoo_
privatestaticboolean hasNextPage(int currentPage, Bd*:y qi
H4ml0SS^
int totalPage){ cs `T7?>
return currentPage == totalPage || totalPage == '#mv- /<t*
|QHDg(
0 ? false : true; })#6BN
} ak 94"<p
Xp"ZK=r
<t>"b|fW
} MDGD*Qn~
~L)9XK^15
n dgG1v%
`h*)PitRa
|_@ '_
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #]>Z4=]v
Squ'd
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ZT:&j4A|0
FGo{6'K(:
做法如下: KP`{ UD)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 AC;ja$A#
<)ozbv Xk
的信息,和一个结果集List:
3=@94i
java代码: Hy`Ee7>
u;R<
7SO i9JU_
/*Created on 2005-6-13*/ NI_.wB{
package com.adt.bo; &i179Qg!
x?v/|
import java.util.List; 6K501!70g6
,)^4H>~V
import org.flyware.util.page.Page; s{\USD6
lcR53X
/** FGY4 u4y
* @author Joa = s^KZV
*/ =oz$uD}?
publicclass Result { ]f#1G$
Loo48
private Page page; c `C
/U7j
>|Ps23J#
private List content; BM9J/24
<RH2G
/** /qp)n">
* The default constructor nA$zp
*/ %2>ya>/M
public Result(){ jI:5[. Y
super(); C\#E1\d
} uf4C+ci
32j@6!
/** I*8i=O@0T
* The constructor using fields 3~v'Ev
* '}3@D$YiM%
* @param page 's#"~<L^e
* @param content y^pzqv
*/ y
qDE|DIez
public Result(Page page, List content){ `(NMHXgG+
this.page = page; Kgh@.Ir
this.content = content; ,?s3%<\2
} E{+V_.tlu
Q v=F'
/** (ns>z7
* @return Returns the content. do0;"O0
(
*/ 5H8]N#Y&
publicList getContent(){ pV`?=[h9
return content; MD`1KC_m
} uXD?s3Wv
)1f8
H,q^
/** q {v?2v{
* @return Returns the page. h^QicvZ
*/ 8~Avg6,
public Page getPage(){ -:Up$6PR
return page; _4H
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} Reci:T(_
a?&{eMEe}
/** }s i{
* @param content hes$LH
* The content to set. ~m4{GzB
*/ ^=kUNyY
public void setContent(List content){ 2 VgFP3
this.content = content; UOh%"h
} m^hi}Am1
hbfTv;=z
/** 8&T6
* @param page L<8:1/d\
* The page to set. Td~CnCor
*/ yn &+ >{
publicvoid setPage(Page page){ Z:51Q
this.page = page; %-u Ra\
} p) #7K
} )q#1C]7m*
cO}`PD$i
gzdR|IBa
gr]:u4}
HHd;<% q
2. 编写业务逻辑接口,并实现它(UserManager, !I3_KuJ5
t\&u
UserManagerImpl) rmVF88/;
java代码: ks{y=@<,
gKyYBr
9k5$rK`
/*Created on 2005-7-15*/ rDr3)*H?0
package com.adt.service; ^eu={0k
=2-!ay:
import net.sf.hibernate.HibernateException; %=C49(/K_
e6O +hC]:
import org.flyware.util.page.Page; 3eOwy~
ZV :cgv
import com.adt.bo.Result; T_T@0`7
<~wr;"S
/** ShFC@)<lJ
* @author Joa 7;]n+QRfm
*/ h?UUd\RU)
publicinterface UserManager { T&@xgj|!)
WKjE^u
public Result listUser(Page page)throws d5aG6/
fC1PPgQ\
HibernateException; Z1@E
0M[O(.x
} POZ5W)F(
W ='c+3O6
;S,k
U{F
{& Pk$Q!
xV]eEOiLM
java代码: 55aJ=T
~96fyk|
4.>rd6BAN-
/*Created on 2005-7-15*/ I.V?O}
package com.adt.service.impl; 7bC1!x*qw
?<_yW#x6
import java.util.List; K
chp%
*RPdU.
import net.sf.hibernate.HibernateException; -)='htiU
2>bTcud>
import org.flyware.util.page.Page; d#Hl3]wT
import org.flyware.util.page.PageUtil; kX0hRX
p_ H;|m9
import com.adt.bo.Result; vUlGE
import com.adt.dao.UserDAO; ?zFeP6C
import com.adt.exception.ObjectNotFoundException; "t[9EbFL
import com.adt.service.UserManager; >gQJ6q
}@+3QHwYU
/** uL.)+E
* @author Joa ]Tv0+ Ao
*/ S!\4,6
publicclass UserManagerImpl implements UserManager { ^T^l3B[
:K-05$K
private UserDAO userDAO; }(*eR F'
gd#j{yI/Xf
/** dp&8:jy
* @param userDAO The userDAO to set. 0[\^Y<ec
*/ H]^hEQ3DT
publicvoid setUserDAO(UserDAO userDAO){ w+,Kpb<x[0
this.userDAO = userDAO; WAd5,RZ?
} Ib8*rL0p<L
{=Z xF
/* (non-Javadoc) >v
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* @see com.adt.service.UserManager#listUser 2N)siH
yJyovfJz.
(org.flyware.util.page.Page) .mr&zq
*/ FabDK :
public Result listUser(Page page)throws {Kbb4%P+h
Bf)}g4nYn
HibernateException, ObjectNotFoundException { :TPT]q
d@
int totalRecords = userDAO.getUserCount(); j@7%%
if(totalRecords == 0) FR bmeq3c
throw new ObjectNotFoundException pJnT \~o
B^;G3+}
("userNotExist"); "L?h@8sa
page = PageUtil.createPage(page, totalRecords); o7_*#5rD
List users = userDAO.getUserByPage(page); #8cpZ]#
returnnew Result(page, users); D90.z"N\i9
} {c(@u6l28
xZMQ+OW2i
} ( o(, ;
zCpsGr
,sa%u Fm
-[h2fqu1
YI877T9>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <l#|I'hP
}fS`jq;
询,接下来编写UserDAO的代码: Fl{@B*3@w
3. UserDAO 和 UserDAOImpl: jV}tjwq
java代码: *6C ]CS
LBcnBo</v
j3W)
/*Created on 2005-7-15*/ xE.yh#?.k
package com.adt.dao; <6!;mb
;cX
6k4ZzQ}
import java.util.List; zp4aiMn1F
q=,
import org.flyware.util.page.Page; ,$H[DX
;?q>F3n
import net.sf.hibernate.HibernateException; .eNeqC
pW
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/** tz6N,4J?
* @author Joa tPQjjoh
*/ I`% ]1{
publicinterface UserDAO extends BaseDAO { UPE9e
k=^~\$e
publicList getUserByName(String name)throws x>ZnQ6x~m]
O4 +a[82
HibernateException; c[E"
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publicint getUserCount()throws HibernateException; VB}4#-dG?
y
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publicList getUserByPage(Page page)throws f4mQDRlD
aSGZF w
HibernateException; N I*x):bx
],W/IDv
} 6T`F'Fk[
?z[k.l+6w
r;7&U<j~Z
$2kZM4
;YfKG8(0
java代码: ?D\6@G:,#@
q{c/TRp7
}hm"49,O
/*Created on 2005-7-15*/ X2PyFe
package com.adt.dao.impl; +";<Kd -
f"Z2,!Z;
import java.util.List; qr<+@Q
~43T$^<w;
import org.flyware.util.page.Page; `[(.Q
.='hYe.
import net.sf.hibernate.HibernateException; "0V8i%a
import net.sf.hibernate.Query; m4m,-}KNi
J
,s9,("
import com.adt.dao.UserDAO; iVUkM3
=[
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/** -50Nd=1
* @author Joa fZ6-ap,u
*/ QnZ7e#@UP
public class UserDAOImpl extends BaseDAOHibernateImpl l&2pUv=
s?9$o
Qq1
implements UserDAO { \*
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/* (non-Javadoc) J Yesk
* @see com.adt.dao.UserDAO#getUserByName (Qp53g
( +x!wX( x
(java.lang.String) [
U`})
*/ TIIwq H+h.
publicList getUserByName(String name)throws 8o7%qWX
3
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HibernateException { !iHJ!
String querySentence = "FROM user in class Z37%jdr
A.|98*U%
com.adt.po.User WHERE user.name=:name"; r;"uk+{i
Query query = getSession().createQuery 0kiV-yc
Ij_h #f
(querySentence); V|q`KOF
query.setParameter("name", name); 0;X0<IV
return query.list(); ?3t]9z
} xC5`|JW
(oG-h"^/
/* (non-Javadoc) TNj WZ
* @see com.adt.dao.UserDAO#getUserCount() x9qoS)@CM
*/ =
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publicint getUserCount()throws HibernateException { `*ml/% \
int count = 0; hlO,mU
String querySentence = "SELECT count(*) FROM U8]BhJr$Q
%gbvX^E?
user in class com.adt.po.User"; wc~k4B9"
Query query = getSession().createQuery lDf:~
IV]2#;OO?
(querySentence); %I^y@2A4`
count = ((Integer)query.iterate().next 0,M1Q~u%.
Y )](jU%o
()).intValue(); 0XLoGQ=
return count; #*v:.0%
} ?,AWXiif
SQhw |QdG
/* (non-Javadoc) WvVf+|Km
* @see com.adt.dao.UserDAO#getUserByPage Eq82?+9
B.ar!*X
(org.flyware.util.page.Page) Y5XhV;16
*/ n u!tk$Q
publicList getUserByPage(Page page)throws G@+AB*Eu
[+_0y[~,tB
HibernateException { 8EC$p} S
String querySentence = "FROM user in class O@)D%*;v
e<E]8GAF
com.adt.po.User"; t$k$Hd';
Query query = getSession().createQuery v0uA]6:
7jtDhsVz
(querySentence); +H `FC
query.setFirstResult(page.getBeginIndex()) E==vk~cz
.setMaxResults(page.getEveryPage()); %.mHV7c)%
return query.list(); w.9'TR
} m{VC1BkZ
9i`sSi8
} iL\eMa
<`Q*I
Y
n^+rxG6L
j{ :>"6
_N2tf/C&=
至此,一个完整的分页程序完成。前台的只需要调用 -A3>+G3[
Y?b4* me
userManager.listUser(page)即可得到一个Page对象和结果集对象 @`S8d%6P
sncc DuS
的综合体,而传入的参数page对象则可以由前台传入,如果用 dZi?Z
+1(L5Do}
webwork,甚至可以直接在配置文件中指定。 1XD|H_JG<j
TxDzGC
下面给出一个webwork调用示例: g0M9v]c
java代码: QmRE<i
XL2iK) A
#->#mshd4
/*Created on 2005-6-17*/ qFwJ%(IQ
package com.adt.action.user; (Tbw@BFk
5:6]ZFW
import java.util.List; @,%IVKg\
- )brq3L
import org.apache.commons.logging.Log; o9 g0fC
import org.apache.commons.logging.LogFactory; |-!
yKB
import org.flyware.util.page.Page; Im0 #_
\
*5Aq\g,n
import com.adt.bo.Result; ~K-_]*[x
import com.adt.service.UserService; -)dS`hM
import com.opensymphony.xwork.Action; Ua](o H
B(l8&
/** yw{;Qm2\7
* @author Joa C?h`i ^ >2
*/ UW@BAj@^@
publicclass ListUser implementsAction{ #nS[]UbwZ
0*umf.R
privatestaticfinal Log logger = LogFactory.getLog 1}>u Y
%^VQw!
(ListUser.class); 9p '#a:
/:o (Ghc?
private UserService userService; *LZ^0c: r
vi-mn)L6#
private Page page; %I>-_el
=3=
$F%
privateList users; ;xMieqz
SWZA`JVK
/* V/@?KC0B5
* (non-Javadoc) 'D1Sm&M2%e
* :!nBTw
* @see com.opensymphony.xwork.Action#execute() QZ:xG:qyk;
*/ 0A.PfqYi
publicString execute()throwsException{ u{>_Pb
Result result = userService.listUser(page); wO&2S-;_K
page = result.getPage(); !v`C-1}70
users = result.getContent(); Zv8I`/4?
return SUCCESS; XDM~H
} '<v_YxEn
!/|^
)d^U
/** '
+*,|;?
* @return Returns the page. (bBr O74lR
*/ KWzJ
public Page getPage(){ Z.v2!u
return page; ~3F\7%Iqc
} 7\e96+j|f
pS
C5$a(
/** TA~YCj$
* @return Returns the users. &GetRDr
*/ KE
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publicList getUsers(){ E
02l=M
return users; HGJfj*JH
} ""2g{!~r
rDvz2p"R
/** ; Da[jFP
* @param page hExw} c
* The page to set. {#Vck\&
*/ y!;PBsU%Sx
publicvoid setPage(Page page){ `4N{x.N
this.page = page; Pa}B0XBWP
} LtDQgel"
pHpHvSI
/** @T6Z3Zj}
* @param users G>q16nS~KP
* The users to set. 5HAIKc
*/ 1FO T
publicvoid setUsers(List users){ <y30t[.E6
this.users = users; {ylhh%t4hi
} Zagj1OV|
"Nx3_mQ
/** A7SE>e>
* @param userService EE<^q?[3^
* The userService to set. ^Nu0+S
*/ \h&ui]V
publicvoid setUserService(UserService userService){ N1Pm4joH%
this.userService = userService; 0-9.u`)#yu
} Z;XiA<|
} AvNU\$B4aG
|y*-)t
;& PK6G
$^1L|KgXp
KOQ9K
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, DIU9Le
S
;; Z
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 +uY)MExs2
7 ?O~3
么只需要: az=(6PX
java代码: U.[?1:v
er[%Nt+99
V>2mzc
<?xml version="1.0"?> 0B;cQSH!q
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork s, 8a1o
G\U'_G>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Qf}^x9'
(^ Q:zU
1.0.dtd"> 3hrODts
UOg4E
<xwork> W"@FRWcd
MGmUgc
<package name="user" extends="webwork- E9yBa=#*c
3Q@HP;<
interceptors"> Q6|~ks+Y
Q.8)_w
<!-- The default interceptor stack name dK=<%)N
# XD-a
--> vGT#BS%
<default-interceptor-ref Du3nK"-g
N2~q\BqA
name="myDefaultWebStack"/> /W6r{Et
-p:X]Ov
<action name="listUser" J} 03 5
RNJUA^{
class="com.adt.action.user.ListUser"> f#W5Nu'*!
<param DjX*2O
^.d97rSm
name="page.everyPage">10</param> nv9kl Q@
<result sPee"9%,
mu(EmAoenQ
name="success">/user/user_list.jsp</result> e[lRY>Pe5
</action> {Y%X
\9S&j(I
</package> KvM}g2"
INyakAmJ}-
</xwork> e (^\0 =u<
'~1uJ0H
Q6?}/p
'e3[m
_TRO2p0
c==` r
C
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 r#K;@wu2
|Q'l&Gt6
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 @Ik@1
4}~zVT0'~
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 U*Hw
t\
f&\v+'[p
-}Jf4k#G
)7e[o8O_6
H nRd
我写的一个用于分页的类,用了泛型了,hoho -'tgr6=|w"
bIP'(B#1K
java代码: 95,{40;X7
*Q<%(JJ
|$r|DX1[
package com.intokr.util; B@,L83
&DMKZMj<Q*
import java.util.List; DO!?]"
I\6u(;@
/** OOEmXb]8
* 用于分页的类<br> SOyE$GoOsx
* 可以用于传递查询的结果也可以用于传送查询的参数<br> cNW [i"
* 0aMw
* @version 0.01 /;%[:x
* @author cheng ;)^eDJ<
*/ *j,5TO-j
public class Paginator<E> { $Q[>v!!X
privateint count = 0; // 总记录数 aqjS 5!qh
privateint p = 1; // 页编号 ~$0Qvyb>
privateint num = 20; // 每页的记录数 0YsC@r47wL
privateList<E> results = null; // 结果 {-sy,EYcw
Q1G?e,Q
/** He4sP`&I
* 结果总数 uLw$`ihw
*/ w,\#)<boyb
publicint getCount(){ KfXE=v{t
return count; X5'QYZ6kv
} }ST9&wi~
#-9;Hn4x
publicvoid setCount(int count){ ,3k"J4|d
this.count = count; 8
0>qqz
} "RG.27
C(:tFuacpw
/** 5-L?JD4&
* 本结果所在的页码,从1开始 #L-3eW=f
* rNL*(PN}lO
* @return Returns the pageNo. Y
9eGDpW
*/ ,6Kx1 c
publicint getP(){ 9HOdtpQOV
return p; BfLh%XC
} qY24Y
>Xq:?}-m2
/** +"!,rZ7,A
* if(p<=0) p=1 lE+v@Kb:
* 6#+&_#9
* @param p '[]V%^F
*/ PrIS L[@
publicvoid setP(int p){ !b"#`O%`
if(p <= 0) E%M~:JuKd?
p = 1; cH()Ze-B
this.p = p; yfS`g-j{~
} jXO*_R
&~+lXNXF
/** 1.]Py" @:
* 每页记录数量 UW+|1Bj_:
*/ R qS2Qo]
publicint getNum(){ %@Nuzdp
return num; taXS>*|B
} cvpcadN[
E3#}:6m
/** Y`QJcC(3
* if(num<1) num=1 A L#"j62
*/ tVUoUl
publicvoid setNum(int num){ .y {qsL^P
if(num < 1) fbKL31PI
num = 1; ,z1X{
this.num = num; {]~b^=qE$
} uE~? 2G
j+:q:6 =
/** lm}mXFf#
* 获得总页数 3&!X8Lhv
*/ C,R_`%b%
publicint getPageNum(){ 3u7^*$S
return(count - 1) / num + 1; /JL2dBy#z
} d18%zY>
F/[vg
/** ^'=J'Q
* 获得本页的开始编号,为 (p-1)*num+1 I\O<XJO)_
*/ ^$aj,*Aj~
publicint getStart(){ . gK*Jpmx
return(p - 1) * num + 1; s@C@q(i6
} i,BE]w
F>,kKR-
/** !tGXh9g
* @return Returns the results. f)\ =LV
*/ `Td 0R!
publicList<E> getResults(){ BlQu9{=n
return results; tWYKW 3~]
} N5 SK_+
AD4KoT&
public void setResults(List<E> results){ q9w6 6R
this.results = results; k#TonT
} S,LW/:,
,~t{Q*#_h
public String toString(){ fr8:L!9
StringBuilder buff = new StringBuilder K
oPTY^
X#<#7.
(); Y!9'Wf/^
buff.append("{"); g4<w6eB
buff.append("count:").append(count); dOArXp`s
buff.append(",p:").append(p); +2=N#LM
buff.append(",nump:").append(num); a!}.l< )
buff.append(",results:").append wn[q?|1
XCO{}wU)>
(results); L2[|g~
buff.append("}"); oJw~g[
return buff.toString(); dV<|ztv
} ;Y#~2eYCz
:e:jILQ[
} ~HsPYc8Fz
.,[zI@9
;w@PnY