Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 r1/9BTPKdJ
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )W*A[c
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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 bk:mk[
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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 \gR%PN
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分页支持类: t ^~Qv
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java代码: bXk(wXX
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package com.javaeye.common.util; 9J$-E4G.M
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import java.util.List; ]i\;#pj}
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publicclass PaginationSupport { EO%"[k
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publicfinalstaticint PAGESIZE = 30; T{)_vQ
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privateint pageSize = PAGESIZE; v1z
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privateList items; n
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privateint totalCount; GglGFXOL-
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privateint[] indexes = newint[0]; 33g$mUB
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privateint startIndex = 0; )6(|A$~C+
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public PaginationSupport(List items, int us+z8Mz
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totalCount){ SG]Sx4fg,Y
setPageSize(PAGESIZE); 0+e
setTotalCount(totalCount); < n/ 2
setItems(items); /xj`'8
setStartIndex(0); -5JN`
} " =6kH,
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public PaginationSupport(List items, int "SRS{-p0
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totalCount, int startIndex){ &f2:aT)
setPageSize(PAGESIZE); KwU;+=_.
setTotalCount(totalCount); ;8a9S0eS
setItems(items); :kFPPx?
setStartIndex(startIndex); 1)5$,+~lL
} OY8P
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public PaginationSupport(List items, int O]'2<;
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totalCount, int pageSize, int startIndex){ cQ
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setPageSize(pageSize); 4AMe>s
setTotalCount(totalCount); $ ^@fV=e
setItems(items); -Aojk8tc
setStartIndex(startIndex); G"w
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} Tl2(%qB
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publicList getItems(){ &gKDw!al
return items; FbRGfHL[
} "By$!R-&
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publicvoid setItems(List items){ @JGFG+J}
this.items = items; )Xa_ry7
} qsQ{`E0
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publicint getPageSize(){ Jy\0y[f*
return pageSize; d::9,~
} YxrMr9>l1
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publicvoid setPageSize(int pageSize){ ?U+hse3e~
this.pageSize = pageSize; ]6M,s0
} p]ujip
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publicint getTotalCount(){ z%#-2&i
return totalCount; 'v9M``
} \Y>b#*m(4
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publicvoid setTotalCount(int totalCount){ .]s? 01Z
if(totalCount > 0){ *@p"
this.totalCount = totalCount; (Ldvx_
int count = totalCount / tDRo)z
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pageSize; T*%rhnTv0
if(totalCount % pageSize > 0) yjsj+K
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count++; >I/@GX/
indexes = newint[count]; 4hc[rN,]
for(int i = 0; i < count; i++){ 3n)$\aBE
indexes = pageSize * ~_Fx2T:X
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i; *5.wwV
} = pn;b1=
}else{ 1Iy1xiP
this.totalCount = 0; AwjXY,2
} Arm'0)B>
} @_?2iN?4Z
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publicint[] getIndexes(){ GcDA0%i
return indexes; 3E^qh03(
} ')0@J`
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publicvoid setIndexes(int[] indexes){ ,
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this.indexes = indexes; ~TsRUT
} }dpTR9j=
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publicint getStartIndex(){ /,\U*'-
return startIndex; e4,SR(O>
} >$TvCw
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publicvoid setStartIndex(int startIndex){ #-@Uq6Y
if(totalCount <= 0) \pfa\,rW
this.startIndex = 0; r7oFG!.?
elseif(startIndex >= totalCount) CgmAxcK
this.startIndex = indexes 8["%e#%`$
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[indexes.length - 1]; Y!_{:2H8p
elseif(startIndex < 0) 3qn_9f ]
this.startIndex = 0; rJkJ/9s
else{ &R?`QB2/
this.startIndex = indexes V:'F_/&X?
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[startIndex / pageSize]; "+T`{$Z=C
} rR :ZTfJs"
} \*=wm$p&*
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publicint getNextIndex(){ ]95VMyN
int nextIndex = getStartIndex() + |T$?vIG[
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pageSize; 8-NycG&)
if(nextIndex >= totalCount) r'j88)^
return getStartIndex(); :CW^$Zvq
else vQyY
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return nextIndex; h?p_jI
} 38D5vT)n
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publicint getPreviousIndex(){ {'tfU
int previousIndex = getStartIndex() - Bh'fkW3
KD,3U/3
pageSize; Q5T3
if(previousIndex < 0) RSh_~qMX
return0; $]
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else !5(DU~S*@S
return previousIndex; F5RL+rU(h
} T>'O[=UWh
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} _wK.n.,S~
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抽象业务类 (87| :{
java代码: ~Ym_ {
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/** TDDMx |{
* Created on 2005-7-12 k:Y\i]#yP
*/ =~h b&
package com.javaeye.common.business; '0+~]4&}q
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import java.io.Serializable; Z! O4hA4
import java.util.List; KCyV |,+n
j=irx5:
import org.hibernate.Criteria; k\.9iI'6
import org.hibernate.HibernateException; 3?a`@C&x
import org.hibernate.Session; =yZq]g6Q
import org.hibernate.criterion.DetachedCriteria; :vb5J33U
import org.hibernate.criterion.Projections; Hvm}@3F|
import W&Fm;m@M
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org.springframework.orm.hibernate3.HibernateCallback; vvv'!\'#
import kEnGr6e
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org.springframework.orm.hibernate3.support.HibernateDaoS ;6P>S4`w
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upport; 7Dbm
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import com.javaeye.common.util.PaginationSupport; $ ubU"
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public abstract class AbstractManager extends {\D&*
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HibernateDaoSupport { NUYKMo1ze
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privateboolean cacheQueries = false; &M}X$k I
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privateString queryCacheRegion; g~y0,0'j1\
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publicvoid setCacheQueries(boolean %US&`BT!
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cacheQueries){ 8l5>t
this.cacheQueries = cacheQueries; 9)1Ye
} Pl/ dUt_
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publicvoid setQueryCacheRegion(String T<pG$4_
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queryCacheRegion){ q k^FyZ<
this.queryCacheRegion = ]qT&6:;-]
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queryCacheRegion; ZX:rqc
} ^7spXfSAd
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publicvoid save(finalObject entity){ dR]-R/1|
getHibernateTemplate().save(entity); 6i[Ts0H%<!
} am]M2+,2Ip
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publicvoid persist(finalObject entity){ BS##nS-[
getHibernateTemplate().save(entity); jG[Vp b
} i7.8H*z'
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publicvoid update(finalObject entity){ N x&/p$d
getHibernateTemplate().update(entity); p3U)J&]c6
} WT ;2aS:
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publicvoid delete(finalObject entity){ Y.Zd_,qy
getHibernateTemplate().delete(entity);
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} %i9 e<.Ot
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publicObject load(finalClass entity, e%JIqKS
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finalSerializable id){ ~JXz
return getHibernateTemplate().load }N[X<9^Z
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(entity, id); (lM,'
} y8~OkdlN#
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publicObject get(finalClass entity, TF/NA\0c$
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finalSerializable id){ 1<BKTMBq?{
return getHibernateTemplate().get M_ukG~/
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(entity, id); * hs&^G
} T/'z,,Y
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publicList findAll(finalClass entity){ !l
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return getHibernateTemplate().find("from e-ta 7R4
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" + entity.getName()); dxs5woP
} TRm#H$
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publicList findByNamedQuery(finalString ]
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namedQuery){ srv4kodj
return getHibernateTemplate G JRl{Y
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().findByNamedQuery(namedQuery); rC-E+%y
} U80=f2
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publicList findByNamedQuery(finalString query, .|O T#"LP
/q IQE&V-
finalObject parameter){ G]ek-[-
return getHibernateTemplate RK!9(^Ja
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().findByNamedQuery(query, parameter); kg^0 %-F
} hU$o^ICH
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publicList findByNamedQuery(finalString query, n|{K_! f
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finalObject[] parameters){ be8T<F
return getHibernateTemplate OvX&5Q5
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().findByNamedQuery(query, parameters); @Y/&qpo$#W
} GI]\
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publicList find(finalString query){ y47N(;vy
return getHibernateTemplate().find \V$qAfP)
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(query); 01?+j%k=m/
} D0\>E}Y E
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publicList find(finalString query, finalObject sjyr9AF
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parameter){ =>;&M)+q
return getHibernateTemplate().find c* ueI5i
* 1;4&/93o
(query, parameter); B"_O!
} 2GptK"MrD
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public PaginationSupport findPageByCriteria ^K<3_D>1>
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(final DetachedCriteria detachedCriteria){ ,4Q4{Tx
return findPageByCriteria 4Im>2)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); gQPw+0w
} QJ XP-
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public PaginationSupport findPageByCriteria >aAM&4
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(final DetachedCriteria detachedCriteria, finalint h+W$\T)
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startIndex){ M^Sa{S*?
return findPageByCriteria D}?p>e|<D
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(detachedCriteria, PaginationSupport.PAGESIZE, [Qnf]n\FJ
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startIndex); EHC7b^|3}
} vxmX5.
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public PaginationSupport findPageByCriteria ^m#tWb)f
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(final DetachedCriteria detachedCriteria, finalint =@!t/LR7kg
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pageSize, NT+.E[J6
finalint startIndex){ 4Fft[S(
return(PaginationSupport) %M
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getHibernateTemplate().execute(new HibernateCallback(){ >/A]C$?3
publicObject doInHibernate hoq2zDjD
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(Session session)throws HibernateException { *a Z1 4
Criteria criteria = PLkS-B
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detachedCriteria.getExecutableCriteria(session); 3=d%WPgQ
int totalCount = ,ucRQ&P
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((Integer) criteria.setProjection(Projections.rowCount 7+P;s,mi7
1d< b\P0
()).uniqueResult()).intValue(); 3:iEt (iCI
criteria.setProjection S"&Gutu3o
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(null); N6._Jb
List items = IAQ<|3Q
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criteria.setFirstResult(startIndex).setMaxResults w1tM !4r
[OCjYC`
(pageSize).list(); e{E\YEc
PaginationSupport ps = %D4)Bqr
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new PaginationSupport(items, totalCount, pageSize, f8;?WSGyD2
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startIndex); vclc%ws
return ps; =Ydrct
} >=0]7k;
}, true); B@(d5i{h
} %>&ex0j]
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public List findAllByCriteria(final Uoe{,4T
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DetachedCriteria detachedCriteria){ 4gen,^ Ij
return(List) getHibernateTemplate }.A]=Ew
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().execute(new HibernateCallback(){ 8JY0]G6
publicObject doInHibernate RB %+|@c
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(Session session)throws HibernateException { K) }1;
Criteria criteria = c]uieig0~
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detachedCriteria.getExecutableCriteria(session); S($/Ov
return criteria.list(); <YW)8J
} Z{B
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}, true); 7su2A>Ix
} qTJ0}F
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public int getCountByCriteria(final Z+v,o1
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DetachedCriteria detachedCriteria){ oMEW5.VX
Integer count = (Integer) 0I.KHIBk
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getHibernateTemplate().execute(new HibernateCallback(){ "kP,v&n
publicObject doInHibernate a>OYJe
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(Session session)throws HibernateException { d}Pfj=W
Criteria criteria = )Jjp^U3Ub
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detachedCriteria.getExecutableCriteria(session); B/;>v
return ;}SGJ7
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criteria.setProjection(Projections.rowCount *<sc[..)
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()).uniqueResult(); Yk|6?e{+)
} *,z/q6
}, true); H1c8]}
return count.intValue(); R$awo/'^
} Ss%Cf6qdWL
} T#qf&Q Z
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用户在web层构造查询条件detachedCriteria,和可选的 1gV?}'jq
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~6;I"0b5
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PaginationSupport的实例ps。 v;\cM/&5
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ps.getItems()得到已分页好的结果集 ?xqS#^Z
ps.getIndexes()得到分页索引的数组 IB&G#2M<
ps.getTotalCount()得到总结果数 uLzE'ZmV
ps.getStartIndex()当前分页索引 >UCg3uFj
ps.getNextIndex()下一页索引 #//xOL3J
ps.getPreviousIndex()上一页索引 ]owgsR
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HX2u{2$
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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 RTh=x.
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一下代码重构了。 <XLaJ;j
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我把原本我的做法也提供出来供大家讨论吧: uaO.7QSwN
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首先,为了实现分页查询,我封装了一个Page类: 'etA1]<N
java代码:
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/*Created on 2005-4-14*/ gbzBweWF
package org.flyware.util.page; Gl>\p
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/** d'W2I*Zc<
* @author Joa i975)_X(
* ,^G+<T6
*/ MU$tX
publicclass Page { y^ skE{
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/** imply if the page has previous page */ ?TpjU*Cxy
privateboolean hasPrePage; _fS\p|W(E
lPZ>#
/** imply if the page has next page */ |aLK_]!
privateboolean hasNextPage; ~qqxHymc
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/** the number of every page */ nx%A s
privateint everyPage; #;!@Pf
=J1V?x=l@
/** the total page number */ /V*SI!C<f
privateint totalPage; 4tm%F\Izy
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/** the number of current page */ rY(7IX
privateint currentPage; DyqqY$ vH(
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/** the begin index of the records by the current sAc1t`
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query */ _b<;n|^
privateint beginIndex; ?'~u)O(n
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/** The default constructor */ t)j$lmQn
public Page(){ >0@w"aKn
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} A4,%l\di<
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/** construct the page by everyPage a2.6S./
* @param everyPage I8!>7`L
* */ BeFyx"NBg
public Page(int everyPage){ wKi#5k2
this.everyPage = everyPage; B{=DnB6
} [[c0g6
5 <k)tF%
/** The whole constructor */ N
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public Page(boolean hasPrePage, boolean hasNextPage, Tl yyJ{~
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((`\i=-o5
int everyPage, int totalPage, Y\WQ0'y
int currentPage, int beginIndex){ w>*Jgc@A*
this.hasPrePage = hasPrePage; ez32k[eV!
this.hasNextPage = hasNextPage; Jd/d\P
this.everyPage = everyPage; JYWoQ[ZO#>
this.totalPage = totalPage; %ud-3u52M8
this.currentPage = currentPage; HlX~a:.7
this.beginIndex = beginIndex; zlP{1z;nV
} k}:;`ST
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/** .+S%hT,v6i
* @return 3ux7^au
* Returns the beginIndex. q`mxN!1[
*/ Iq%<E:+GL
publicint getBeginIndex(){ F_0D)H)N@
return beginIndex; <5%*"v
} 47(_5PFb#
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/** *g*"bi*
* @param beginIndex kttJTP77t
* The beginIndex to set. :q3w;B~
*/ \%r0'1f
publicvoid setBeginIndex(int beginIndex){ WYF8?1dt +
this.beginIndex = beginIndex; .f0qgmIyL
} .WKJ37od
aHC%:)ww:
/** 7~J>Ga
* @return A-L1vu;
* Returns the currentPage. BPv+gx(>k
*/ rZwSo]gp
publicint getCurrentPage(){ )SP"V~^Wn
return currentPage; [*O>Lk
} tJu:N'=Dy
?,7!kTRH
/** `W}pAmhj
* @param currentPage w_>\Yd [
* The currentPage to set. Vaf,
*/ 7:F0?l*
publicvoid setCurrentPage(int currentPage){ ##''d||u
this.currentPage = currentPage; 8y5"X"U
} |pZ7k#%
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/** 00D.Jn
* @return kjPf%*3
* Returns the everyPage. {,uSDIOj$
*/ 4tUoK[p
publicint getEveryPage(){ 68GH$ji
return everyPage; 0xDn!
} l?"^2in.
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/** T^]]z}k
* @param everyPage [)}P{y
[&
* The everyPage to set. [Y!HQ9^LEp
*/ xU%]G.k
publicvoid setEveryPage(int everyPage){ Hd;NvNS
this.everyPage = everyPage; h-Y>>l>PW0
} .?CaU
}l+_KA
/** p=UW ^95
* @return Wn6m$ =
* Returns the hasNextPage. DM v;\E~D
*/ &a'mG=(K_c
publicboolean getHasNextPage(){ V?*fl^f
return hasNextPage; k@%5P-e}
} +C;;4s)
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/** Has}oe[
* @param hasNextPage h{o,*QL
* The hasNextPage to set. ^W=hs9a+F
*/ 837:;<T
publicvoid setHasNextPage(boolean hasNextPage){ 7;@YR
this.hasNextPage = hasNextPage; `L$Av9X\
} NUb$PT
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/** m4W (h6
* @return p q?# X0
* Returns the hasPrePage. #t1? *4.p
*/ 0LC]%x+"
publicboolean getHasPrePage(){ X}
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return hasPrePage; %4rlB$x
} #O~pf[[L
FTEC=j$ln
/** w(_:+-rqQ<
* @param hasPrePage }8l+Jd3"
* The hasPrePage to set. % +
*/ Am3j:|>*
publicvoid setHasPrePage(boolean hasPrePage){ Fv,c8f
this.hasPrePage = hasPrePage; 8zRw\]?
} .e5@9G.jb
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/** =>>Dnp
* @return Returns the totalPage. Pl|I{l*o(`
* R~A))4<%%
*/ Y:+:>[F
publicint getTotalPage(){ m,hqq%qz
return totalPage; =;n>#<
} jQz^)8)B
w=-{njMz6&
/** IeChz d
* @param totalPage kz1Z K
* The totalPage to set. ;j;U9-oh
*/ hx%UZ <a
publicvoid setTotalPage(int totalPage){ B^/Cx
this.totalPage = totalPage; S9[Up}`
} SK/}bZ;f
8Rw:SU9H?T
} -$%~EY}
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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 SmyJ@.L"
.'+JA:3R
个PageUtil,负责对Page对象进行构造: xzMpT ZQ
java代码: LfrjC@_y
n|=yw6aV'
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/*Created on 2005-4-14*/ z-0
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package org.flyware.util.page; y&4im;X0
WH $*\IGJL
import org.apache.commons.logging.Log; `.VkR5/
import org.apache.commons.logging.LogFactory; MD1d
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/** NJ}xqg
* @author Joa b0%#=KMi
* wN0?~
*/ ?|2m0~%V=
publicclass PageUtil { S)2 U oj
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privatestaticfinal Log logger = LogFactory.getLog W^:g_
k
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(PageUtil.class); q_;# EV
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/** rY6bc\?`x
* Use the origin page to create a new page M tDJ1I%
* @param page }LIf]YK
* @param totalRecords \FO
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* @return .$G^c
*/ =`(\]t"I
publicstatic Page createPage(Page page, int JKXIxw>q
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totalRecords){ C}XB%:5H5
return createPage(page.getEveryPage(), tnmz5Q
G
in
page.getCurrentPage(), totalRecords); c3Ig4 n0Y>
} 5oD%~Fk l
}2?-kj7
/** <&M5#:u
* the basic page utils not including exception aJNsJIY+
5FNf)F
handler Tkf4`Gxd
* @param everyPage K,HR=5
* @param currentPage Mr K?,7*Xi
* @param totalRecords #DTBdBh?I
* @return page !Nhq)i
*/ 7 Uu
publicstatic Page createPage(int everyPage, int vs.}Bou]
Q},uM_"+
currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); zgpvI~Ck
currentPage = getCurrentPage(currentPage); {-5b[m(
int beginIndex = getBeginIndex(everyPage, ]7dal [i
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currentPage); 3o__tU)B
int totalPage = getTotalPage(everyPage, n-lDE}K9%B
+7)/SQM5
totalRecords); l>>,~
boolean hasNextPage = hasNextPage(currentPage, na4^RPtN\e
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totalPage); e-{4qt
boolean hasPrePage = hasPrePage(currentPage); oxqD/fY
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returnnew Page(hasPrePage, hasNextPage, ~hA;ji|I
everyPage, totalPage, 0.t1p(x;
currentPage, %1]Lc=[j
[SLBA_d
beginIndex); P\|i<Ds_M
} nr9cG/"
] yXrD`J!
privatestaticint getEveryPage(int everyPage){ ?jBh=X\]:
return everyPage == 0 ? 10 : everyPage; &4l>_
} B7qiCX}pD
@)wNINvD
privatestaticint getCurrentPage(int currentPage){ i_;]UvP
return currentPage == 0 ? 1 : currentPage; !;C *Wsp}
} &5wM`
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privatestaticint getBeginIndex(int everyPage, int B,dKpz;kFg
Mj@ 0F
2hy
currentPage){ BcTV5Wcr
return(currentPage - 1) * everyPage; 5/{gY{
} =G2A Ufn
e_pyjaY!s
privatestaticint getTotalPage(int everyPage, int IC7S
+v
{YgB?kt5
totalRecords){ ?_c*(2i&^
int totalPage = 0; q^w3n2
FmRa]31W
if(totalRecords % everyPage == 0) ~v<,6BS<$Z
totalPage = totalRecords / everyPage; !=c&U.B
else [P_1a`b
totalPage = totalRecords / everyPage + 1 ; KIUa
S}*%l)vfR
return totalPage; mI~k@ !3
} ]LhNP}c
!M&B=vk4
privatestaticboolean hasPrePage(int currentPage){ Z-+p+34ytq
return currentPage == 1 ? false : true; ^^Tu/YC9x
} 8.Ty
,7Z
LA^H213N|
privatestaticboolean hasNextPage(int currentPage, V<!E9/4rS
=w!14@W
int totalPage){ VXAgp6
return currentPage == totalPage || totalPage == vb.`rj6
q,a|lH
0 ? false : true; 9f4#b8
} COK7 i^
cy6P=k*
^dR5fAS
} OC]_b36v
i'%:z]hp9
?qQRA|n*
29#;;n}p
x+9aTsZ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 AT U
2\Y
r`L$[C5I
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 =e,2/Ep{i
xCV3HnZ
做法如下: g.N~81A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @`ttyI^1f
{ LJRdV
的信息,和一个结果集List: vF=d`T<
java代码: 9c1n
r,x;q
pr[[)[]/
/*Created on 2005-6-13*/ H{P"$zj`l
package com.adt.bo; toEmIa~o6
|!)3[<.
import java.util.List; (v^L2Po
9)QvJ87e@7
import org.flyware.util.page.Page; T%xB|^lf
'7{0k{
/** Au,}5=+`P
* @author Joa 4PEJ}BW
*/ x=bAR%i~
publicclass Result { ;Q2p~-0Q
j%KLp4J/e
private Page page; W<3nF5!
fO.gfHI
private List content; @fbB3
G~e`O,+
/** y@G5I>v
* The default constructor %97IXrE
*/ D;|4ZjM-
public Result(){ 13Ee"r
super(); XH0R:+s
} q7wd9 6G:
8_ns^6XK5p
/** @M"h_Z1#
* The constructor using fields s"G6aM
* h2u>CXD
* @param page eGblQGRS
* @param content 81/Bn!
*/ )=X8kuB~
public Result(Page page, List content){ ^m{kn8
this.page = page; M*E4:A9_M
this.content = content; ZSMOq4Y 9
} >"S'R9t
`{/z\
/** N@^?J@#V
* @return Returns the content. >b |l6#%
*/ xk}YeNVj
publicList getContent(){ ~/hP6*
return content; o;\0xuM@
} v.,C"^W
t}`|\*a
/** z$`=7 afp
* @return Returns the page. Vr f` :%
*/ s0.yPA
public Page getPage(){
7+j@0v\
return page; 'd1E~A
} >\$qF
nKh._bvfX
/** BJk\p.BVN
* @param content l<{]%=Qg
* The content to set. U\
y?P:yy
*/ *KFsO1j
public void setContent(List content){ 2[Q*?N
this.content = content; uyxU>yHV<g
} 4fZ$&)0&
;vF8V`f
/** t[F tIj6
* @param page 2:/'
* The page to set. ~c :e0}
*/ o
1#XM/Z
publicvoid setPage(Page page){ l0u6nGkh
this.page = page; MlsF?"H p
} o'%F*>#v
} As1Er[>
l8%x(N4
E[6JHBE*r
>RBq&'f
g^^%4Y
2. 编写业务逻辑接口,并实现它(UserManager, )"jG)c^1*
<h
U ZD;
UserManagerImpl) HPCgv?E3
java代码: m^O:k"+ !
$ZXy&?4
@| %t<{y^I
/*Created on 2005-7-15*/ usR19 _E-
package com.adt.service; sxO_K^eD
rc*&K#? B
import net.sf.hibernate.HibernateException; M`KrB5a+6
zV4%F"-
import org.flyware.util.page.Page; <=cj)
X`:(-3T
import com.adt.bo.Result; =1^Ru*G
?qw&H /R
/** )dJM
* @author Joa nPfVZGt
*/ .
%tc7`k8
publicinterface UserManager { -d%bc?
g84~d(\?
public Result listUser(Page page)throws o]MQ)\r
ZHICpL
HibernateException; ]BP/KCjAI<
>?b/_O
} t\{q,4
sG0cN;I]t
%6L!JN
T6Ue\Sp'
\@['V
java代码: 8:$kFy\A'
6}x^T)R
1b;Aru~l
/*Created on 2005-7-15*/ 2j4VW0:
package com.adt.service.impl; 6H VS0
s3_i5,y
import java.util.List; +tdt>)a
?O\n!c
import net.sf.hibernate.HibernateException; qp
2*Z~JM
import org.flyware.util.page.Page; -CT?JB
import org.flyware.util.page.PageUtil; RX=C)q2c
N^h,[
import com.adt.bo.Result; i <bFF03*S
import com.adt.dao.UserDAO; \0(QO8.
import com.adt.exception.ObjectNotFoundException; Puily9#
import com.adt.service.UserManager; N~\1yQT
6N~~:Gt
/** JF%+T yMe
* @author Joa *J8j_-i,R
*/ 6rt.ec(
publicclass UserManagerImpl implements UserManager { ?*4&Z.~J
6g@j,iFy
private UserDAO userDAO; \ zhT1#O
#?!)-Q%
/** 4rwfY<G
* @param userDAO The userDAO to set. "]kaaF$U%
*/ 9j:?s;B
publicvoid setUserDAO(UserDAO userDAO){ 0RYh4'=F
this.userDAO = userDAO; A37Z;/H~k
} HP. j.
aMZ6C <N
/* (non-Javadoc) + To{Tm-
* @see com.adt.service.UserManager#listUser sA3 4`ZAa
qK.8^{b
(org.flyware.util.page.Page) +S^Uw'L$=T
*/ b&HA_G4
public Result listUser(Page page)throws C%}FVO\c
RQ9fA1YP
HibernateException, ObjectNotFoundException { {{SQL)yJ
int totalRecords = userDAO.getUserCount(); .9lx@6]+
if(totalRecords == 0) /]F3t]FlC
throw new ObjectNotFoundException , YTuZS
RA>xol~xy
("userNotExist"); ud'r?QDM
page = PageUtil.createPage(page, totalRecords); R\A5f\L9
List users = userDAO.getUserByPage(page); !wJ~p:vRdY
returnnew Result(page, users); Eae]s8ek9
} Ls5|4%+&
_;v4]MU
} QI=",vmau
x}AWWmXv
HS="t3
^Ml)g=Fq
p8%x@%k
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 jNaK]
rVt6tx
询,接下来编写UserDAO的代码: ?bmP<(N5/
3. UserDAO 和 UserDAOImpl: qI^6}PB
java代码: #)GL%{Oa
Jq<&`6hn
jU@qQ@|
/*Created on 2005-7-15*/ &P&M6v+
package com.adt.dao; ,l&Dt,
TW{.qed8^
import java.util.List; CbS- Rz:
D;.-e
import org.flyware.util.page.Page; XcR2]\
A%k@75V@
import net.sf.hibernate.HibernateException; (05/}PhB`
s34{\/'D+
/** Gi6sl_"q
* @author Joa HP:ee+n
*/ 52C>f6w
publicinterface UserDAO extends BaseDAO { ^UEI`_HO0
7xMvf<1P
publicList getUserByName(String name)throws pzg|?U
sn@gchO9s
HibernateException; ,=Xr'7w,
*6df|q
publicint getUserCount()throws HibernateException; g&`e2|[7
ht(RX
publicList getUserByPage(Page page)throws DJS0;!#
|O
HIk5Q'e k
HibernateException; _o'ii
VDuD
?y>P
} vYKKv%LE
q}*(rR9/Br
UP58Cln*
)%- FnW
]p\7s
java代码: #OqQD6
J LT10c3
#@w8wCj
/*Created on 2005-7-15*/ }cn46L%/
package com.adt.dao.impl; `J'xVq#O
K9njD#/
import java.util.List; &-:ZM0Fl
SGXXv
import org.flyware.util.page.Page; f<=<:+
P%8
Gaa=
import net.sf.hibernate.HibernateException; sG=D(n1
import net.sf.hibernate.Query; Nv,1F
='`z
import com.adt.dao.UserDAO; =kp#v
4c_TrNwP
/** V:fz
* @author Joa |F=!0Id<
*/ Ur6UE2
public class UserDAOImpl extends BaseDAOHibernateImpl }3E@]"<cVR
MCZTeYnx
implements UserDAO { $]2srRA^A
Q>8F&p?R
/* (non-Javadoc) [a:yKJ[
* @see com.adt.dao.UserDAO#getUserByName 0M7Or)qN
$5yH(Z[[
(java.lang.String) ]i(tou-[i
*/ )a
AKO`
publicList getUserByName(String name)throws d&BocJ
x_pS(O(C
HibernateException { I<`K;El'
String querySentence = "FROM user in class eee77.@y-p
DzydS=`w
com.adt.po.User WHERE user.name=:name"; 0"ksNnxK
Query query = getSession().createQuery )r3}9J
48hu=,)81*
(querySentence); =iW!Mq
query.setParameter("name", name); j]U sb_7
return query.list(); UbNA|`H
} jfP2n5X83
L.ScC
/* (non-Javadoc) GvSSi'q~B
* @see com.adt.dao.UserDAO#getUserCount() K1>X%f^
*/ 9 js!gJC
publicint getUserCount()throws HibernateException { mFfw*,M
int count = 0; $M{MOehZ
String querySentence = "SELECT count(*) FROM ^,*ED Yz
xP#vAR
user in class com.adt.po.User"; *oopdGue
Query query = getSession().createQuery ZUePHI-dP
_1Iy /T@1
(querySentence); qB6@OS
count = ((Integer)query.iterate().next 4Vl_vTz{i
W; yNg
()).intValue(); "O{j}QwY
return count; '#RzX8|v<
} r<VZEbm)
a~q_2S]h
/* (non-Javadoc) 5$f
vI#NO<
* @see com.adt.dao.UserDAO#getUserByPage TRP#b 7nC
jBZlNEw
(org.flyware.util.page.Page) QZ?# ixvJ
*/ &.XlXihnt
publicList getUserByPage(Page page)throws ,)/gy)~#
-FQ!
HibernateException { 5&?[Vt
String querySentence = "FROM user in class [Jv0^"]
j5Kw0Wy7
com.adt.po.User"; ^j]"!:h
Query query = getSession().createQuery ~puXZCatN
b3R1L|@
(querySentence); :btb|^C
query.setFirstResult(page.getBeginIndex()) aF*KY<w
.setMaxResults(page.getEveryPage()); CD]hi,B_J
return query.list(); G>Fk
)
} \WS2g"(
8T6LD
} DJ_[{WAV
er@"4R0
?QA![
[v47_ 5O
mm}y/dO~}
至此,一个完整的分页程序完成。前台的只需要调用 be?>C
5
LLy w9y1
userManager.listUser(page)即可得到一个Page对象和结果集对象 %+ln_lgD:
]oT8H?%*Y
的综合体,而传入的参数page对象则可以由前台传入,如果用 )/HbmtX qI
eTg8I/)%B
webwork,甚至可以直接在配置文件中指定。 gu?e%]X3
R[_Q}W'HG
下面给出一个webwork调用示例: (~>uFH
java代码: LSewMj
Lk%`hsv
/{1s U}k-
/*Created on 2005-6-17*/ yyPQ^{zD
package com.adt.action.user; -M]B;[^
9NF2a)&~
import java.util.List; X,5}i5'!
/x%h@Cn!
import org.apache.commons.logging.Log; #jrtsv]
import org.apache.commons.logging.LogFactory; ->Z9j(JU
import org.flyware.util.page.Page; nm"]q`(K
f^JiaU4 [
import com.adt.bo.Result; ]MD,{T9l\>
import com.adt.service.UserService; u<L<o2
import com.opensymphony.xwork.Action; [U5@m]>^
4X-" yQ<U
/** ~7p!t%;$
* @author Joa vCvjb\S
*/ ML _$/
publicclass ListUser implementsAction{ ^b M\:z"M
1`hmD1d
privatestaticfinal Log logger = LogFactory.getLog ( p(/
)Ehi8
(ListUser.class); \;XDPC j
2[!3!@.
private UserService userService; 6ZO6O=KD
#ovausK[7
private Page page; 7MWd(n-
Pj-.oS2dA
privateList users; Ky0}phGRu
sKy3('5;
/* R$XHjb)
* (non-Javadoc) QhhL_vP
* "Jahc.I
* @see com.opensymphony.xwork.Action#execute() Vc[aNpE
*/ r'J="^k{
publicString execute()throwsException{ Bd'X~Vj<
Result result = userService.listUser(page); t1JU_P
page = result.getPage(); 2jf73$F
users = result.getContent(); e{EC#%x_
return SUCCESS; kzE<Y
} Z";&1cK
sYEh>%mo^C
/** J&2J6Eq
* @return Returns the page. \gsJ1@
*/ mjQZ"h0
public Page getPage(){ @T"-%L8PL
return page; a(J@]X>'
} s.X
.SJ
{+~ JTrp
/** YpOcLxFL
* @return Returns the users. z!M #
*/ y
Nc@K|
publicList getUsers(){ z''ejq
return users;
rp
'^]Zx
} /0sw rt.
lfAiW;giJ
/** TU6(Q,Yi|
* @param page >'lv Zt
* The page to set. ;AG&QdTMh
*/ yhkKakg,)
publicvoid setPage(Page page){ u`.3\Geh
this.page = page; 7lx"
X0w*m
} {Gr"lOi*@
z`qb>Y"xf3
/** i]#"@xQ
* @param users Z2U6<4?1%
* The users to set. (@ 1>G
^%
*/ |KR8=-!7
publicvoid setUsers(List users){ 'fs
tfk
this.users = users; PNz]L
} x?UAj8z6
{2%'=v
/** _l"=#i@L
* @param userService vM@8&,;
* The userService to set. f\rE{%
*/ ;reBJk
publicvoid setUserService(UserService userService){ !kG |BJ$j
this.userService = userService; t~H0Qeb[v=
} )oALB vX
}
Y(
=P9Tc"2PN
q@G}Hjn
MQQQaD:v
}rvX}
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, >~0~h:M+
r$1b=m,0d
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Hd\.,2a"
f}~=C2R1<!
么只需要: ? 'qyI^m@
java代码: !F:mDZeY
[_KV;qS%/
S
n<X
<?xml version="1.0"?> EJP] E)
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Ge @qvP_
+I\54PBws
1.0//EN" "http://www.opensymphony.com/xwork/xwork- %Z+**>1J
]HaX.Z<
1.0.dtd"> <-mhz`^
v}J0j
<xwork> UGlHe7
V.9p4k`
<package name="user" extends="webwork- I94-#*~I
lUaJC'~p
interceptors"> _s+G02/q1
+!GJ
<!-- The default interceptor stack name gKY6S?
g${JdxR:
--> #K`0b$
<default-interceptor-ref 0K6My4d{
.R@s6}C`}=
name="myDefaultWebStack"/> aZ|?i
}
8f<y~L_(`
<action name="listUser" t 9t
'9
H|0-Al.{
class="com.adt.action.user.ListUser"> lX-i <0`
<param p>O/H1US;
fJP *RVz
name="page.everyPage">10</param> JQ;.+5
N<K
<result gkX7,J-0
0Vrs bkS
name="success">/user/user_list.jsp</result> qcouZO
</action> %Oo
f/q
C0K:
ffv;<
</package> 7x=4P|(\}
@)x*6 2r+
</xwork> J>k
6`gw
aNs8T`
j74hWz+p4
/\_n5XI1
+I-BqA9
h1"|$
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 1hlU
6=Y
xmEom
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。 Y+o\?|q-E
$Mj\ 3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 zRa2iCi
ar\K8mj
Q-!gO
hkyO_ns
0)cSm"s
我写的一个用于分页的类,用了泛型了,hoho g1?9ge1
SB08-G2
java代码:
)#8g<]q
*Wvk~
@ZjO#%Ep/
package com.intokr.util; Z:<an+v|5
-%]1q#C>@
import java.util.List; rQ_]%ies8
Ssuz%*
/** {;E6jw@
* 用于分页的类<br> }vh4ix
* 可以用于传递查询的结果也可以用于传送查询的参数<br> q*4U2_^.
* ~ +>ehU
* @version 0.01 S 6_:\Q
* @author cheng -ycdg'v
*/ |IV7g*J89
public class Paginator<E> { |`Noj+T47I
privateint count = 0; // 总记录数 )`(]jx!
privateint p = 1; // 页编号 cC>Svf[CzK
privateint num = 20; // 每页的记录数 ^[r1Dk
privateList<E> results = null; // 结果 ~".@;Q
^H7xFd|>
/** P$0c{B4I
* 结果总数 b1cVAfUP
*/ <ShA_+Nd
publicint getCount(){ T&MhSJf#
return count; <xF]ca
} $2}#):`
$.kJBRgV*
publicvoid setCount(int count){ Vs{\ YfF
this.count = count; 8PH4v\tJEK
} @M B)B5
uDXV@;6<
/** |6b~c{bt
* 本结果所在的页码,从1开始 }% q-9
* rm9>gKN;#
* @return Returns the pageNo. A7%/sMv
*/ OA=~i/n~
publicint getP(){ })P!7t
return p; .gmS1ju
} +0z7}u\x
e3W~6P
/** ZAU#^bEQB
* if(p<=0) p=1 @y~kQ5k
* GM'yOJo
* @param p __Ksn^I
*/ PU,$YPrZ
publicvoid setP(int p){ X ?[ )e
if(p <= 0) (AtyM?*
p = 1; c`p'5qz
this.p = p; DBB&6~;?
}
UWqD)6
tE{M
/** R'zi#FeP
* 每页记录数量 >(ip-R
*/ {4,],0bjx/
publicint getNum(){ bKGX>
%-
return num; H!Q72tyo
} Y
0Fq-H
Ze8.+Ee
/** .kg 3>*
* if(num<1) num=1 &e:+;7
*/ dH;2OWM
publicvoid setNum(int num){ -5 PVWL\
if(num < 1) vg[3\!8z[
num = 1; @-Ql6k
this.num = num; oC49c~`8
} n`&D_AbQ
OVDuF&0
/** oV0 45G
* 获得总页数 6(d6Uwc`
*/ 9l&q}
publicint getPageNum(){ ]q{_i
return(count - 1) / num + 1; bI|G
%
} 2O[sRm)
kt)Et
/** +sjzT[ Dn
* 获得本页的开始编号,为 (p-1)*num+1 ;z.niX .fx
*/ g,EDE6`8
publicint getStart(){ @}g3\xLiK
return(p - 1) * num + 1; :R=6Ku>
} 4xmJQ>/
:tU^
/** +71<B>L
* @return Returns the results. qc
@cdi
*/ ?l?l<`sTO
publicList<E> getResults(){ czD"mI!
return results; Wy7w zt
} v{ >3)$1
JOY&YA$U
public void setResults(List<E> results){ b;UDgq8v
this.results = results; 4/`;(*]Fv
} -i2rcH
?#=xx.cF
public String toString(){ 6d6cZGS[:
StringBuilder buff = new StringBuilder SK'h!Ye5Z
sV
a0eGc
(); .6C/,rQ?c
buff.append("{"); }u
O YF
buff.append("count:").append(count); d7vPZ_j^z
buff.append(",p:").append(p); /"?DOsJ.
buff.append(",nump:").append(num); >bf.T7wy
buff.append(",results:").append A5yVxSF
196a~xNV
(results); <z,)4z++
buff.append("}"); ==m[t-
9x
return buff.toString(); #\lvzMjCC
} u7hu8U=
n>q!m@ }<
} A|r3c?q
lEFd^@t
~ h3G}EH