Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 s"`~Xnf
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Mu[lk=jC
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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 [8sYE h
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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 Ul_Zn
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分页支持类: }h45j84)
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java代码: lK=Is
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package com.javaeye.common.util; ,Zn6T"[$
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import java.util.List; //2O#Fg{/
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publicclass PaginationSupport { uS`}
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publicfinalstaticint PAGESIZE = 30; 9m)$^U>oz
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privateint pageSize = PAGESIZE; @^UgdD,BS,
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privateList items; }S uj=oFp
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privateint totalCount; 1DB{"8ov
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privateint[] indexes = newint[0]; DlUKhbo$g
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privateint startIndex = 0; =SLG N`m3
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public PaginationSupport(List items, int mBErU6?X,A
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totalCount){ BrE#.g Jq
setPageSize(PAGESIZE); paIjXaU1Mb
setTotalCount(totalCount); ?0/$RpFEM#
setItems(items); x!_5/
setStartIndex(0); $UH:r
} y<FC7
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public PaginationSupport(List items, int Nz2V aZ
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totalCount, int startIndex){ n>, :*5"G
setPageSize(PAGESIZE); 'M~`IN`
setTotalCount(totalCount); *ai~!TR
setItems(items); $\NqD:fgb
setStartIndex(startIndex); e' l9
} 7(+4^
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public PaginationSupport(List items, int ev;&n@k_I
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totalCount, int pageSize, int startIndex){ D ;> 7y}\
setPageSize(pageSize); 'z8FU~oU
setTotalCount(totalCount); t,fec>.
setItems(items); uM`i!7}
setStartIndex(startIndex); jlj ge=#c2
} 66pjWS
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publicList getItems(){ "KP]3EyPc
return items; >; MJm
} Q<V(#)*
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publicvoid setItems(List items){ Xb%Q%"?~
this.items = items; vWoppt
} /*y5W-'d^
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publicint getPageSize(){ ^ 0YQlT98
return pageSize; >*{k~Y-G
} zfKO)Itd
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publicvoid setPageSize(int pageSize){ h_(M#gG
this.pageSize = pageSize; Wz'!stcp
} We{@0K/O
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publicint getTotalCount(){ G*N[t w
return totalCount; `Qo37B2
} Mm@G{J\\
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publicvoid setTotalCount(int totalCount){ **h4M2'C
if(totalCount > 0){ AZQQge
this.totalCount = totalCount; ?) y}HF
int count = totalCount / a|z-EKV
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pageSize; FB?~:7+'
if(totalCount % pageSize > 0) v%qOW)].
count++; ! eZls
indexes = newint[count]; wU+r]SK@
for(int i = 0; i < count; i++){ $~6MR_Yq
indexes = pageSize * 6HK1?
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i; s0' haU
} 32 i6j
}else{ 7{}E{/
this.totalCount = 0; 7_2D4CI
} sg7h&<Xx
} CnB[ImMs(A
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publicint[] getIndexes(){ YjDQ`f/
return indexes; gFp3=s0~
} {ze69 h
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publicvoid setIndexes(int[] indexes){ hP+4{F*}-
this.indexes = indexes; |s!
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} ^Q`5+
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publicint getStartIndex(){ +4%~.,<_to
return startIndex; Cy?]o?_?
} 1]:,Xa+|S
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publicvoid setStartIndex(int startIndex){ [gBf1,bK
if(totalCount <= 0) 2%WeB/)9
this.startIndex = 0; &"%Ws{Qn]
elseif(startIndex >= totalCount) 7=Muq]j2
this.startIndex = indexes our
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[indexes.length - 1]; iKaX8c,zI
elseif(startIndex < 0) 8s6[-F5
this.startIndex = 0; "?zWCH
else{ zj r($?
this.startIndex = indexes eV*QUjS~
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[startIndex / pageSize]; ,<L4tp+y0
} r[!~~yu/o
} &Gh,ROo4
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publicint getNextIndex(){ h7+"*fN
int nextIndex = getStartIndex() + /= ;,lC
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pageSize; +=J$:/&U
if(nextIndex >= totalCount) oUnb-,8n
return getStartIndex(); 9$$ Ijf
else F)cCaE;
return nextIndex;
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} i$] :Y`3h
@HbRfD/!
publicint getPreviousIndex(){ xK6`|/e
int previousIndex = getStartIndex() - clU ?bF~e1
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pageSize; e^eJ!~0
if(previousIndex < 0) t}R!i-D|HB
return0; 8j>V?'Szk
else S} UYkns*
return previousIndex; 1!^BcrG.
}
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} Q$U.vF7BnP
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抽象业务类 qR
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java代码: HjK8y@j
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/** Mrk3r/
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* Created on 2005-7-12 [l^XqD D4
*/
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package com.javaeye.common.business; Z~SAlhT
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import java.io.Serializable; OT\D;Z"__I
import java.util.List; u;9iuc`*
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import org.hibernate.Criteria; 0\!Bh^++1
import org.hibernate.HibernateException; i{EQjZ
import org.hibernate.Session; ]@9W19=P!P
import org.hibernate.criterion.DetachedCriteria; A]m*~Vj]
import org.hibernate.criterion.Projections; Cl3vp_
import YMu#<ZG
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org.springframework.orm.hibernate3.HibernateCallback; vx?KenO}
import AT
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org.springframework.orm.hibernate3.support.HibernateDaoS KOe]JDU
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upport; !y_L~81?
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import com.javaeye.common.util.PaginationSupport; &PPnI(s^K
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public abstract class AbstractManager extends {Yxvb**
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HibernateDaoSupport { je$H}D
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privateboolean cacheQueries = false; #8t=vb3
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privateString queryCacheRegion; D>jtz2y=D
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publicvoid setCacheQueries(boolean iyCH)MA
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cacheQueries){ EB&hgz&_
this.cacheQueries = cacheQueries; Ijiw`\;
} 1^o})9
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publicvoid setQueryCacheRegion(String !jl^__
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queryCacheRegion){ P\ P=1NM
this.queryCacheRegion = =?Ry,^=b
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queryCacheRegion; ])y)]H#{
} ^) s6`:
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publicvoid save(finalObject entity){ JUw|nUnl?
getHibernateTemplate().save(entity); 0*]0#2Z
} prO&"t
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); X_-/j.
} "d/54PKWx
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publicvoid update(finalObject entity){ &O+S[~
getHibernateTemplate().update(entity); ZWyf.VJ
} ^'N!k{x
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publicvoid delete(finalObject entity){ =^M Q 4
getHibernateTemplate().delete(entity); :Hitx
} >H euf"V
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publicObject load(finalClass entity, 8B6(SQp%
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finalSerializable id){ S8;c0}-
return getHibernateTemplate().load /!&eP3^
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(entity, id); Xl$r720ZJr
} ow (YgM>t
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publicObject get(finalClass entity, 7zQGuGo(
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finalSerializable id){ kazgI>"Q8
return getHibernateTemplate().get }rVLWt
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(entity, id); :ldI1*@i<
} aAu%QRq
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publicList findAll(finalClass entity){ \HoVS
return getHibernateTemplate().find("from pTQ7woj}
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" + entity.getName()); R,!aX"]|
} |.~2C14[
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publicList findByNamedQuery(finalString (F R
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namedQuery){ 4[r:DM|8
return getHibernateTemplate ywjD.od"v
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().findByNamedQuery(namedQuery); mk-L3H1@J3
} %E":Wv
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publicList findByNamedQuery(finalString query, KmF+3g~#s
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finalObject parameter){ z\J#d 1e
return getHibernateTemplate &C/,~pJ1S
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().findByNamedQuery(query, parameter); SsL>K*t5
} r)w]~)8
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publicList findByNamedQuery(finalString query, Gnqun%
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finalObject[] parameters){ P^/e!%UgC
return getHibernateTemplate #Nv0d|0\
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().findByNamedQuery(query, parameters); !E/%Hv1
} oH
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publicList find(finalString query){ uc;,JX!bN
return getHibernateTemplate().find X 2('@Yh
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(query); D7N` %A8
} {<^PYN>`
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publicList find(finalString query, finalObject 4d]T`
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parameter){ t7$2/C
return getHibernateTemplate().find 0K^G>)l
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(query, parameter); p~u11rH
} WkY>--^
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public PaginationSupport findPageByCriteria c:`&QDF
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(final DetachedCriteria detachedCriteria){ ,OO0*%
return findPageByCriteria kasx4m]^
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); OY#=s!]
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} S$fCO$bU
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public PaginationSupport findPageByCriteria T EqCoeR
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(final DetachedCriteria detachedCriteria, finalint |(1z ?Spbe
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startIndex){ Y]1b39O
return findPageByCriteria )e:u 6]
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(detachedCriteria, PaginationSupport.PAGESIZE, >RT02Ey>
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startIndex); K5q9u-7
} k*xgF[T
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public PaginationSupport findPageByCriteria E2{SKIUm
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(final DetachedCriteria detachedCriteria, finalint &mp@;wI6@
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pageSize, -J*jW
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finalint startIndex){ VFwp .1oa!
return(PaginationSupport) 6tmn1:
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getHibernateTemplate().execute(new HibernateCallback(){ <P1sK/IZb
publicObject doInHibernate i;B)@op.#
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(Session session)throws HibernateException { .B9rG~
Criteria criteria = wrW768WR
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detachedCriteria.getExecutableCriteria(session); t.oP]_mI
int totalCount = q6v%HF-q4
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((Integer) criteria.setProjection(Projections.rowCount "8Y4;lbN.q
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()).uniqueResult()).intValue(); kC)ye"r
criteria.setProjection VDq?,4Kb
7*r7Q'
(null); $n?@zd@53
List items = LHz-/0[
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criteria.setFirstResult(startIndex).setMaxResults "(rG5z3P
NrdbXPHceN
(pageSize).list(); .DSmy\FI5
PaginationSupport ps = {` Lem
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new PaginationSupport(items, totalCount, pageSize, xTW$9>@\m
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startIndex); N&t+*kF_
return ps; A/EW57v"
} %g4G&My@J
}, true); PN n{Rt
} BK8)'9/
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public List findAllByCriteria(final ^H1B62_
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DetachedCriteria detachedCriteria){ EsU-Ckb_2:
return(List) getHibernateTemplate +," /z\QO
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().execute(new HibernateCallback(){ d&QB?yLd
publicObject doInHibernate D"m]`H
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(Session session)throws HibernateException { q}#4bB9
Criteria criteria = _f u?,
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detachedCriteria.getExecutableCriteria(session); g9`z]qGWS:
return criteria.list(); 4~3 N;]X
} lXS.,#lp
}, true); T8,?\7)S9
} !giL~}j(R
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public int getCountByCriteria(final Ph'P<h:V
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DetachedCriteria detachedCriteria){ I=)u:l c
Integer count = (Integer) 0[JJ
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getHibernateTemplate().execute(new HibernateCallback(){ [Az<E3H"
publicObject doInHibernate /L8Q[`;.
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(Session session)throws HibernateException { ~e5hfZv|w
Criteria criteria = ew#t4~hh
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detachedCriteria.getExecutableCriteria(session); %># VhK
return %(IkUD
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criteria.setProjection(Projections.rowCount A&OU;j]
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()).uniqueResult(); l.c*,9
} >weY_%a
}, true); |#);^z_
return count.intValue(); +pcpb)VL
} =1noT)gCR
} j>(O1z7
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用户在web层构造查询条件detachedCriteria,和可选的 v"VpE`z1#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ?CgqHmf\\(
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PaginationSupport的实例ps。 IvFxI#.ju
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ps.getItems()得到已分页好的结果集 B zmmE2~*
ps.getIndexes()得到分页索引的数组 A{Jp>15AVg
ps.getTotalCount()得到总结果数 Tji G!W8
ps.getStartIndex()当前分页索引 qU(,q/l
ps.getNextIndex()下一页索引 3 xSt -MA
ps.getPreviousIndex()上一页索引 -\OvOkr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ib(q9!L
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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 DlHt#Ob7
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一下代码重构了。 v803@9@
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我把原本我的做法也提供出来供大家讨论吧: A
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首先,为了实现分页查询,我封装了一个Page类: s9R#rwIc
java代码: J!40`8i
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/*Created on 2005-4-14*/ 'aYUF&GG
package org.flyware.util.page; V\$'3(*
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/** TPjElBh
* @author Joa {z~n`ow
* AgEX,SPP
*/ 5L6_W-n{
publicclass Page { u^HC1r|%
pZo:\n5o
/** imply if the page has previous page */ |]--sUx:
privateboolean hasPrePage; BG>fLp
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/** imply if the page has next page */ 1:!_AU?
privateboolean hasNextPage; 6#[
usj:I`>
/** the number of every page */ >Q5et1c
privateint everyPage; ?VUU[h8"v5
k!?sHUAj
/** the total page number */ d}@b 3
privateint totalPage; K/xn4N_UX
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/** the number of current page */ t1Ty.F)r
privateint currentPage; nHAET
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/** the begin index of the records by the current :1>h,NKC>
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query */ Yatd$`,hW
privateint beginIndex; 5`Q*
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/** The default constructor */ 4= 7#=F1
public Page(){ \9
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} O52B
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/** construct the page by everyPage JWZG)I]r
* @param everyPage =VC"X ?N
* */ V{jQ=<)@e
public Page(int everyPage){ @c;XwU]2t
this.everyPage = everyPage; 0m2%ucKw
} m*bTELb
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/** The whole constructor */ 1SAO6Wh
public Page(boolean hasPrePage, boolean hasNextPage, C{{RU7iqc&
4S%s=vw
` nd/N#
int everyPage, int totalPage, 77 g<`}{
int currentPage, int beginIndex){ [3K& cX}B
this.hasPrePage = hasPrePage; pc/x&VY%
this.hasNextPage = hasNextPage; v11Uw?CM
this.everyPage = everyPage; !uZ)0R
this.totalPage = totalPage; >X@4wP7l
this.currentPage = currentPage; "SMRvi57T
this.beginIndex = beginIndex; hFMJDGCw>Q
} ke2zxX2f
U/}("i![Dy
/** V ,+&.A23
* @return 6Qc
*:(GE
* Returns the beginIndex. $jkzm8{W
*/ :@rq+wvP
publicint getBeginIndex(){ Lm-f0\(
return beginIndex; dDu8n+(8 L
} > J.q3
*XUJv&ZN
/** ^;8dl.;
* @param beginIndex et`1#_o
* The beginIndex to set. v[Mh[CyB
*/ 3VZ}5
publicvoid setBeginIndex(int beginIndex){ KPi_<LuK
this.beginIndex = beginIndex; ?4`f@=}'K
} $)YalZ
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/** QLm#7ms*y
* @return ,+P2B%2c
* Returns the currentPage. 'G1~
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*/ wC>}9OM
publicint getCurrentPage(){ 7v']wA r]
return currentPage; Wq2Bo*[*
} ~|Nj+A
2%?Kc]JY9
/** $x~U&a
* @param currentPage gB_gjn\
* The currentPage to set. w,T-vf
*/ g+j\wvx0
publicvoid setCurrentPage(int currentPage){ uv|RpIv e:
this.currentPage = currentPage; sB@9L L]&|
} Nf5zQ@o_y
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/** Vg^yjP{sv
* @return $6l^::U
* Returns the everyPage. %zKTrsMZ
*/ 7VIfRN{5n
publicint getEveryPage(){ &q7}HO/ @
return everyPage; Mdw"^x$7
} ~hxW3e
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/** *b4W+E
* @param everyPage 5_\1f|,
* The everyPage to set. 1rIL[(r4
*/ J4]tT pu"K
publicvoid setEveryPage(int everyPage){ !59,<N1Iu
this.everyPage = everyPage; Q<Q?#v7NX
} yHo#v:>?p
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/** !ra,HkU'
* @return z8dBfA<z
* Returns the hasNextPage. /g>]J70
*/ 3dx.%~c
publicboolean getHasNextPage(){ WCYVon bg"
return hasNextPage; ?!.L#]23f
} % !>@m6JK
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/** $ghlrV;:ct
* @param hasNextPage b:PzqMh{G
* The hasNextPage to set. Bun^EJ)
*/ e>UU/Ks
publicvoid setHasNextPage(boolean hasNextPage){ ~}_S]^br
this.hasNextPage = hasNextPage; >l b9 j>
} W%1/:_
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/** l h?[wc
* @return 3V]08
* Returns the hasPrePage. )b~+\xL5J
*/ hZ|8mV
publicboolean getHasPrePage(){ % kaV?j
return hasPrePage; M_O) w^
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} ~#dfZa&
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/** 9T\\hM)k
* @param hasPrePage !S'!oinV
* The hasPrePage to set. 8{
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*/ z:8ieJ)C
publicvoid setHasPrePage(boolean hasPrePage){ o?d`o$
this.hasPrePage = hasPrePage; L@S1C=-/
} R].xT-1
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/** BS2'BS8
* @return Returns the totalPage. ;>%wf3e
* gSHN,8.
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*/ ,:{+-v(
publicint getTotalPage(){ mLV0J '
return totalPage; (~NR."s;
} Qoa&]]
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/** Eb8~i_B-
* @param totalPage 1 XpqnyL&
* The totalPage to set. 3U!
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*/ y\n#`*5k
publicvoid setTotalPage(int totalPage){ sD9OV6^{?K
this.totalPage = totalPage; g^{a;=
} )m
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} ~uG/F?= Q:
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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 xJin%:O
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个PageUtil,负责对Page对象进行构造: Zul@aS
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java代码: f jMmlp
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/*Created on 2005-4-14*/ (_Th4'(@Y
package org.flyware.util.page; M}`T-"qf
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import org.apache.commons.logging.Log; ]l"9B'XR
import org.apache.commons.logging.LogFactory; SB:z[kfz|
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/** od^o9(.W^
* @author Joa %"e hZd0r
* lpjby[S
*/ k&:~l@?O
publicclass PageUtil { @W=:r/
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privatestaticfinal Log logger = LogFactory.getLog Qnx?5R-}ZU
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(PageUtil.class); ;<=z^1X9
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/** L+lX$k
* Use the origin page to create a new page zhh6;>P
* @param page H|3CZ=U?
* @param totalRecords qykI[4
* @return >ktekO:H
*/ 6ZQ$5PY
publicstatic Page createPage(Page page, int D 77$aCt
P)[QC
totalRecords){ WHr:M/qD
return createPage(page.getEveryPage(), v?o("I[ C
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page.getCurrentPage(), totalRecords); N.vkM`Z
} A{wk$`vH
>+%p}l:<\
/** F<O<=Ww
* the basic page utils not including exception =%{E^z>1
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handler -3SRGr
* @param everyPage C9j5Pd5q1L
* @param currentPage "uBr]N:
* @param totalRecords 6Z-[-0o+g
* @return page N::.o+1
*/ 'EB5#
publicstatic Page createPage(int everyPage, int b{,vZhP-
j?(@x>HA
currentPage, int totalRecords){ m@yx6[E#
everyPage = getEveryPage(everyPage); {sUc2vR
currentPage = getCurrentPage(currentPage); Bm;@}Ly=G
int beginIndex = getBeginIndex(everyPage, ):V)Hrq?x
P9]95.j
currentPage); !/Wv\qm
int totalPage = getTotalPage(everyPage, CYNpbv
?xt${?KP
totalRecords); _mDvRFq
boolean hasNextPage = hasNextPage(currentPage, R/&C}6Gn
>+S* Wtm5
totalPage); 'D?sRbJ=
boolean hasPrePage = hasPrePage(currentPage); 2'WdH1UrBc
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returnnew Page(hasPrePage, hasNextPage, 9QkIMJf0e
everyPage, totalPage, $]b&3_O$N8
currentPage, CM+wkU ?,
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beginIndex); pXe]hnY
} *4 Kc "M
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privatestaticint getEveryPage(int everyPage){ !e0/1 j=
return everyPage == 0 ? 10 : everyPage;
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} e0<L^|S
leEzfbb{'.
privatestaticint getCurrentPage(int currentPage){ tUs{/Je
return currentPage == 0 ? 1 : currentPage; [~ |e:
} gR{.0e
q?oJ=]m"
privatestaticint getBeginIndex(int everyPage, int 7
P]Sc
"Oy&6rrr
currentPage){ l5_%Q+E_
return(currentPage - 1) * everyPage; ]GPUL>7
} Q$2^m(?;
|)Sx"B)
privatestaticint getTotalPage(int everyPage, int tA9(N>[*
1;9 %L@
totalRecords){ >V3pYRA
int totalPage = 0; 4JjO.H
qzu%Pp6If
if(totalRecords % everyPage == 0) l7GLN1#m
totalPage = totalRecords / everyPage; ^i~'aq
else (9D,Ukw
totalPage = totalRecords / everyPage + 1 ; P
C
2n5{H fpY
return totalPage; :6Sb3w5h
} a<{+
JU5
kx3]A"]>'
privatestaticboolean hasPrePage(int currentPage){ f%Bm x{Ttq
return currentPage == 1 ? false : true; Hy1f,D
} ACxjY2
\6v*c;ZF
privatestaticboolean hasNextPage(int currentPage, E- rXYNfy
(`Q_^Bfyl
int totalPage){ `!g
XA.9Uv
return currentPage == totalPage || totalPage == zgHF-KEV
UkBr4{+aE
0 ? false : true; ;hp?wb
} ppM^&6x^
'^.}5be&
\)T4NN
} &:*|K xX
?\Z-3l%M
y-CVyl
Mkadl<
<ba+7CK]w
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。 u<{uUui}$v
VR_ bX|
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 jR&AQ-H&
^aO\WKkA
做法如下: ?{I]!gI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zbL6TP@=
H">
}yD
的信息,和一个结果集List: k ihO~<
java代码: EJ3R{^
afa7'l=^i
D>Ph))QI
/*Created on 2005-6-13*/ IT0*~WMZ
package com.adt.bo; c\pPwG
H@xIAL
import java.util.List; g:nU&-x#R
G|Y9F|.!
import org.flyware.util.page.Page; ua
vv
}n JG<rY
/** +EBoFeeIG
* @author Joa onj:+zl
*/ bbU{ />yW
publicclass Result { ,, G6L{&Z
o$DJL11E
private Page page; D;al(q
vMOit,{
private List content; jVpk) ;vC
_'E,g@
/** ` `R;x
* The default constructor {?9s~{Dl
*/ ! G+/8Q^
public Result(){ Q!VPk~~(
super(); 7)Rx-
} Y-WYQ{
Q[k7taoy
/** ~IKPi==@,
* The constructor using fields ,&IBj6%Y
* cTeEND)
* @param page It@ak6u?
* @param content O2Mo ~}
*/ b%<i&YY#
public Result(Page page, List content){ ryq95<lF
this.page = page; w(9.{zF|vQ
this.content = content; eOQUy+
} kEE8cW3
\}e1\MiZ
/** mSzBNvci
* @return Returns the content. f9g#pyH4
*/ $Q|t^(
publicList getContent(){ \Podyh/;?
return content; ^.J
F?2T/
} O9k9hRE]z
aMFUJrXo
/** ~sQN\]5VW
* @return Returns the page. ;?i(WV}ee
*/ YQ_3[[xT
public Page getPage(){ cFoDR
return page; mq?5|`
} RYaf{i`
8 JUUK(&Z
/** V(Ps6jR"BS
* @param content rQbL86+
* The content to set. t,.MtU>K@
*/ $Rsf`*0-
public void setContent(List content){ hb"t8_--c
this.content = content; gC#PqK~
} OgfmyYMtc
h&Ehp
/** Q-%Q7n'c
* @param page ^Q]*CU+C
* The page to set. s45Y8!c
*/ Yo
c N@s
publicvoid setPage(Page page){ #s1O(rLRl
this.page = page; vvLm9Tw
} Poacd;*
} rs3Uk.Z^'
M? oK@i
EW{z?/
+xwz.:::
W$0<a@
2. 编写业务逻辑接口,并实现它(UserManager, fi%u]
6v0^'}
UserManagerImpl) OZ1+` 4 v
java代码: RV|: mI
02} &h
tqIz$84G
/*Created on 2005-7-15*/ s&p*.I]@>
package com.adt.service; 0}c*u) ,
l/_3H\iM
import net.sf.hibernate.HibernateException; !=#E/il,
3C8'0DB
import org.flyware.util.page.Page; rO/mK$
y5.Z <Y
import com.adt.bo.Result; G|yX9C]R
Mu18s}
/** glh2CRUj
* @author Joa "';'*x
*/ z_eP
publicinterface UserManager { 5,'?NEyw
[SgP1>M
public Result listUser(Page page)throws r:y*l4
86~HkHliv
HibernateException; /!UuGm
phUno2fH
} 0yXUVKq3
}.7!@!q.
0%}$@H5i
_n2PoE:5@P
@<\f[Znto
java代码: Y2j>lf?8
~ @Ib:M
Bm%:Qc*
/*Created on 2005-7-15*/ xmTa$tR+
package com.adt.service.impl; N<:5 r
*J?QXsg
import java.util.List; d5]9FIj
Y*O7lZuF%
import net.sf.hibernate.HibernateException; S)z
jfJR
,:QG%Et
import org.flyware.util.page.Page; [bJ/$A
import org.flyware.util.page.PageUtil; X4&{/;$
:KZI+
import com.adt.bo.Result; 7CABM
import com.adt.dao.UserDAO; )__vPPko i
import com.adt.exception.ObjectNotFoundException; F$ x@]
import com.adt.service.UserManager; ^DVr>u
bc5+}&W
/** ";9cYoKRY
* @author Joa +}>whyX1
*/ ?{$Q'c_I
publicclass UserManagerImpl implements UserManager { yEtSyb~GK
J& +s
private UserDAO userDAO; /9|1eSUa
)dG7$,g
/** X^?<, Y)1.
* @param userDAO The userDAO to set. R*E/E
*/ H]Q Z4(
publicvoid setUserDAO(UserDAO userDAO){ 9IMtqL&
this.userDAO = userDAO; 0kpRvdEr-
} {LY$
:HRJ49a
/* (non-Javadoc) XY1NTo.=
* @see com.adt.service.UserManager#listUser ${KDGJ,^
z}s0D]$+x
(org.flyware.util.page.Page) ?.IT!M}DR
*/ y)|Q~8r
public Result listUser(Page page)throws E*7B5
V{$(#r
HibernateException, ObjectNotFoundException { ?y'KX]/
int totalRecords = userDAO.getUserCount(); ]}8<h5h)
if(totalRecords == 0) ._-^58[
throw new ObjectNotFoundException 2<yi8O\
_C&2-tnp
("userNotExist"); <m`HK.|~
page = PageUtil.createPage(page, totalRecords); I_'S|L
List users = userDAO.getUserByPage(page); }-)2CEj3L%
returnnew Result(page, users); [U]*OQH`e
} A"\kdxC
4t|g G`QW7
} Vur$t^zE
LS Na
%U)/>Z
$91c9z;f^
D.j'n-yw
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 p<'#f,o
~o= Sxaf
询,接下来编写UserDAO的代码: oU$Niw9f
3. UserDAO 和 UserDAOImpl: m7^aa@^m
java代码: z;GnQfYG
$=4T# W=m
nu}$wLM
/*Created on 2005-7-15*/ 6/wAvPB$
package com.adt.dao; CwTx7
^qa
<O?iJ=$
import java.util.List; /lx\9S|
(i1FMd}G
import org.flyware.util.page.Page; 1@P/h#_Vr
k)b}"' I
import net.sf.hibernate.HibernateException; c#$B;?
8V;@yzIha
/** {tV)+T
* @author Joa %8>s :YG
*/ 4g b2$" !
publicinterface UserDAO extends BaseDAO { A$WE:<^
{^Vkxf]
publicList getUserByName(String name)throws BP,"vq $'+
[95(%&k.Q
HibernateException; gtyo~f
MmI4J$F
publicint getUserCount()throws HibernateException; rBkLwJ]
\s<{V7tq
publicList getUserByPage(Page page)throws JaXT
B"e
75r>~@)*
HibernateException; LpGplDlB
&&xBq?
} #Bg88!-4
CuR\JKdRo
]IoJ(4f
mFjX
,fpu@@2
java代码: e ,/I}W
5:Pp62
<h4"^9hL
/*Created on 2005-7-15*/ $]%;u: Sa
package com.adt.dao.impl; /WRS6n
8s/gjEwA
import java.util.List; r )ZUeHt}w
}Xr-xh\v
import org.flyware.util.page.Page; w0)V3
4[
M!x
import net.sf.hibernate.HibernateException; MGfDxHg]
import net.sf.hibernate.Query; @HxEp;*NH"
6b~Zv$5^Y-
import com.adt.dao.UserDAO; ]{{A/ j\
n`2d
/** 81eDN6
M\
* @author Joa 3xxQL,FV
*/ 8B JxD<
public class UserDAOImpl extends BaseDAOHibernateImpl J_C<Erx[O
(8TB*BhQ_
implements UserDAO { ]@Y8 !
,
K}tl,MMU
/* (non-Javadoc) !jN}n)FSq
* @see com.adt.dao.UserDAO#getUserByName %%`Nq&'
upg?
(java.lang.String) ;n%SjQ'%
*/ 4*}[h9J}\
publicList getUserByName(String name)throws l
Q]&:%^\
rmu5K$pl
HibernateException { p
@&>{hi@
String querySentence = "FROM user in class !Y>lAx d
6v(}<2~
com.adt.po.User WHERE user.name=:name"; 9 [v=`
Query query = getSession().createQuery p~6/+ap
"+/%s#&
(querySentence); I 8vv
query.setParameter("name", name); MP(R2y
return query.list(); btHN
} seC]=UJh#>
eqU2>bIf
/* (non-Javadoc) 0vuL(W8)
* @see com.adt.dao.UserDAO#getUserCount() RbzSQr>a\
*/ /:3:Ky3
publicint getUserCount()throws HibernateException { 0?KXQD
int count = 0; -G e5gQ=
String querySentence = "SELECT count(*) FROM rZ2X$FO@
b6:A-jb*I
user in class com.adt.po.User"; PElC0qCn[
Query query = getSession().createQuery @wy|l)%
P?p>'avP
(querySentence); J(JsfU4
count = ((Integer)query.iterate().next G3'>KMa.
?YWfoH4mS
()).intValue(); ,(dg]7
return count; bO 2>ced
} GmP)"@O](;
:i_818h!?[
/* (non-Javadoc) 4e~^G
* @see com.adt.dao.UserDAO#getUserByPage u.sF/T=6f
N-`Vb0;N
(org.flyware.util.page.Page) 8@]*X,umc
*/ W^npzgDCo
publicList getUserByPage(Page page)throws n|2`y?
Z>gxECi
HibernateException { *GleeJWz
String querySentence = "FROM user in class 7 4Xk^8
wI><kdz
com.adt.po.User"; NAjY,)>'K
Query query = getSession().createQuery G6(kwv4
W2/FGJD
(querySentence); vw5f.8T;w
query.setFirstResult(page.getBeginIndex()) vQ/}E@?u
.setMaxResults(page.getEveryPage()); ^]l^q'?>:
return query.list(); z%$ E6Im
} E9z^# @s
kP~'C'5Ys
} %Xs3Lz
wmKM:`&[5
@ODwO;_R5
E
.^5N~.
9zSHn.y
至此,一个完整的分页程序完成。前台的只需要调用 CT,caa
DP\s-JpI[
userManager.listUser(page)即可得到一个Page对象和结果集对象 'QGacV
B?Ac
的综合体,而传入的参数page对象则可以由前台传入,如果用 jXA!9_L7
g? N~mca$
webwork,甚至可以直接在配置文件中指定。
N1,=5P$
#=F"PhiX`
下面给出一个webwork调用示例: )OQhtxK
java代码: WeDeD\zy
+13h*
wI.i\S
/*Created on 2005-6-17*/ 2{;&c
package com.adt.action.user; J$6h%Eyo
AQn>K{M
import java.util.List; :*bv(~FW
%x@
D i`;
import org.apache.commons.logging.Log; >dKK [E/[d
import org.apache.commons.logging.LogFactory; b ~DtaGh
import org.flyware.util.page.Page; [
[]'U'
PN9^ sLx=
import com.adt.bo.Result; u.;zz'|
import com.adt.service.UserService; ^kZfE"iE2
import com.opensymphony.xwork.Action; "<o[X ?u
:VwU2
/** xg=}MoX
* @author Joa 2VmQ%y6e"
*/ -
s[=$pDU
publicclass ListUser implementsAction{ piYv}4;:(
OQzJRu)mF#
privatestaticfinal Log logger = LogFactory.getLog X"WKgC g$
T=r-6eN
(ListUser.class); r=GF*i[3
Q#C;4)e
private UserService userService; _y#omEx
HT]W2^k
private Page page; #qkokV6`
ZeewGa^r
privateList users; $YZsaw
HQHFD0hv
/* KHwzQ<Z3
* (non-Javadoc) AA][}lU:5
* z _qy>
* @see com.opensymphony.xwork.Action#execute() .5Y%I;~v
*/ EvZ;i^.8LS
publicString execute()throwsException{ *9:oTN
Result result = userService.listUser(page); LhM{LUi
page = result.getPage(); I9O9V[
users = result.getContent(); V3;4,^=6Dd
return SUCCESS; s( @w1tS.
} &8'.Gwm}
F) w.q
/** <p@c%e,_
* @return Returns the page. XL[/)lX{
*/ (<sZ8n=AD
public Page getPage(){ l;i,V;@t
return page; !0ly1T 9
} Y.I-hl1<r
9pPb]v,6
/** 6OYXcPW'
* @return Returns the users. {FzL@!||
*/ Ol ,;BZHc\
publicList getUsers(){ 36>pa
return users; z0J$9hEg89
} .DSn
H6O
(IXiwu
/** ^l1tQnj)7
* @param page =H*}{'#
* The page to set. shW$V93<
*/ U3r[ysf
publicvoid setPage(Page page){ ( Lj{V}^
this.page = page; \)'nxFKqV
} `|K,E
b?Wg|D
/** 3L/qU^`
* @param users =ark?<E
* The users to set. %M8Egr2|0
*/ a%*l]S0z"
publicvoid setUsers(List users){ ~ILig}I
this.users = users; H
<CsB
} i^P@?
ZJ(/cD
/** Z=%+U _,
* @param userService * d6[kY
* The userService to set. xGbr>OqkTX
*/ h&4ufx6
publicvoid setUserService(UserService userService){ ps0wN%tA
this.userService = userService; f`<j(.{9F
} <%eY>E
} `B+%W
yu"Ii-9z
2}j2Bhc
`mPmEV<
^_4TDC~h
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, '^ '4C'J
1@IRx{v$
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 fs4pAB #F
QFoZv+|
么只需要: H e]1<tx
java代码: E/cA6*E[.<
~`2w
ul
}GvoQ#N
<?xml version="1.0"?> G%)?jg@EA
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork GypZ!)1
8xhXS1
1.0//EN" "http://www.opensymphony.com/xwork/xwork- GZT}aMMSJ
}C>Q
1.0.dtd"> 1"46OCu{
9dA(f~
<xwork> .lu:S;JSnS
Rde_I`Ru
<package name="user" extends="webwork- >4TJH
lB}8
FzmCS@yA
interceptors"> k*|dX.C:
2rHw5Wn]~
<!-- The default interceptor stack name Wu)ATs}
Sp)KtMV
--> SCeZt [
<default-interceptor-ref RAKQ+Y"nl
ANSv ZqKh
name="myDefaultWebStack"/> 9[DQ[bL
^&<~6y}U^
<action name="listUser" 47I:o9E
sBuJK'
class="com.adt.action.user.ListUser"> LLmgk"
<param tW5\Ktjno
475yX-A
name="page.everyPage">10</param>
N>`+{
<result "M6a_rZ2W
FW7+!A&F
name="success">/user/user_list.jsp</result> Ff>Y<7CQ
v
</action> pH#&B_S6z=
b
qB[vPsI
</package> R7*Jb-;$!
Wq)'0U;{$
</xwork> A{h
hnrr8
, >Y.!
_yjM_ALjo
L*tXy>&b.
kN9S;o@)
X@ +:O-$
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 &n<jpMB
a#H=dIj
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。 *F:]mgg
Y^LFJB|b4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 8DTk<5mW~
Af=%5%
cNC\w%
yWIieztp
GG"0n{>0
我写的一个用于分页的类,用了泛型了,hoho Js+d4``W
^FgNg'"[3
java代码: !~UI~-i'
OfTcF_%
xmKa8']x
package com.intokr.util; j-gLX
;TSnIC)c
import java.util.List; CkoPno
a2/r$Tgm
/** 9?D7"P+
* 用于分页的类<br> s
cR-|GuZ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> &_4A6
* UTA0B&aB
* @version 0.01 @usQ*k
* @author cheng +azPpGZ=
*/ }#!o^B8
public class Paginator<E> { v ;MI*!E
privateint count = 0; // 总记录数 _zh}%#6L
privateint p = 1; // 页编号 UShn)3F
privateint num = 20; // 每页的记录数 '5ky<
privateList<E> results = null; // 结果 u-UUF
1@)]+* F*z
/** gbpm::
* 结果总数 k6JB%m\E
*/ 8e\a_R*(|
publicint getCount(){ k`g+
return count; w2]1ftY
} `RGZ-Q{_
&8"a 7$
publicvoid setCount(int count){ ^\N2
Iu>6
this.count = count; p5F[( H|9
} ^%_B'X9
8YkP57Y%[Z
/** ;x^&@G8W`
* 本结果所在的页码,从1开始 EoU}@MjM~
* L*FmJ{Yf
* @return Returns the pageNo. %c^]Rdl
*/ h>mQ; L
publicint getP(){ KH pxWq
return p; KXw
\N!
} um,/^2A
N)poe2[
/** /2'\ya4B
* if(p<=0) p=1 nr&G4t+%Hv
* z*yN*M6t
* @param p u"T5m
*/ );))kYr
publicvoid setP(int p){ zN5i}U=|r
if(p <= 0) e}[$ =
p = 1; 4]
?
this.p = p; yE"hgdL
} )W 57n)]
d1y(Jt
/** 8.k"kXU@n
* 每页记录数量
IR/0gP
*/ GQF7]j/
publicint getNum(){ (59<Zo
return num; yv3myaS
} |lJXI:GG
1pzU=!R?-O
/** D%^EG8i n.
* if(num<1) num=1 7%7_i%6wP
*/ tm]75*?
publicvoid setNum(int num){ fiw~"2U
if(num < 1) B|extWwu
num = 1; z[t$[Qg
this.num = num; ybS7uo
} J|xqfY@+
a*SJHBB
/** { +C>^b
* 获得总页数 QJ"Bd`wc
*/ vpXS!o>/Sn
publicint getPageNum(){ 6bb=;
return(count - 1) / num + 1;
5j]}/Aq
} d=>5%$:v
Z]SCIU @+
/** TP^.]IO-
* 获得本页的开始编号,为 (p-1)*num+1 kJDMIh|g
*/ d+&V^qLJ
publicint getStart(){ m k -"
U7;
return(p - 1) * num + 1; v0$6@K;M4G
} 9MHb<~F
ny=CtU!z
/** 2o\\qEYg
* @return Returns the results. up:e0di{
*/ Rb9Z{Clq>
publicList<E> getResults(){ aaaC8;.
return results; tkuN$Jl
} u8?ceM^r
*f4KmiQ~%
public void setResults(List<E> results){ M/1Q/;0P
this.results = results; 4&y_+
} L\-T[w),z7
j ^_G
public String toString(){ 2iH,U
StringBuilder buff = new StringBuilder .5dZaI)
@Rx/]wyH
(); Hfc^<q4a.
buff.append("{"); {qx"/;3V
buff.append("count:").append(count); QGLm4 Wl9
buff.append(",p:").append(p); .IKK.G
buff.append(",nump:").append(num); _&dGo(B
buff.append(",results:").append aB'<#X$x
sL\|y38'
(results); pnqjATGU
buff.append("}"); _puQX@i
return buff.toString(); {X"X.`p
} jM7}LV1Ck
+u)'
} l|&|+u#
o_5|L9
0\h2&