Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `w}"0+V
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 '{~ej:
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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 T@XiG:b7
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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 !{LwX Kf
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分页支持类: Q[^d{e*l
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java代码: d+;~x*
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package com.javaeye.common.util; %qhaVM$]
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import java.util.List; K9iR>put
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publicclass PaginationSupport { uNjy&I:
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publicfinalstaticint PAGESIZE = 30; D]REZuHOI
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privateint pageSize = PAGESIZE; `7`iCYiTy
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privateList items; j.sf FS
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privateint totalCount; MG|NH0k
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privateint[] indexes = newint[0]; FK>rc3 q
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privateint startIndex = 0; .+.Pc_fv
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public PaginationSupport(List items, int /C"E*a
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totalCount){ {v(3[7
setPageSize(PAGESIZE); AyWCb
setTotalCount(totalCount); H3JWf
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setItems(items); U}NNbGQj
setStartIndex(0); pLRHwL.
} +-ue={'
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public PaginationSupport(List items, int
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totalCount, int startIndex){ )57OZ
setPageSize(PAGESIZE); `#~@f!';
setTotalCount(totalCount); HRk+2'wjAz
setItems(items); =d9%ce
setStartIndex(startIndex); Xo
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} }wn GOr
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public PaginationSupport(List items, int *%8dW
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totalCount, int pageSize, int startIndex){ f?)qZPM
setPageSize(pageSize); 'O
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setTotalCount(totalCount); 6;ICX2Wq'
setItems(items); &iTsuA/7
setStartIndex(startIndex); 8<xJmcTEwO
} 9K)2OX;$w
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publicList getItems(){ K}6}Opr,Tt
return items; {aU~[5L3(
} 3?C$Tl2G8
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publicvoid setItems(List items){ s:M:Ff
this.items = items; ]F,5Oh :OY
} ]^dXB0
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publicint getPageSize(){ B<i1UJ5
return pageSize; _TH'v:C
} *5wb8[
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publicvoid setPageSize(int pageSize){ =5+:<e,&
this.pageSize = pageSize; j
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} o;}o"-s
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publicint getTotalCount(){ ="MG>4j3.F
return totalCount; 5'6Oan7dL:
} ~zi&u46
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publicvoid setTotalCount(int totalCount){ Nq-qks.&
if(totalCount > 0){ .^uNzN~
this.totalCount = totalCount; s+,JwV?b
int count = totalCount / iielAj*b
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pageSize; [i\K#O +f
if(totalCount % pageSize > 0) F@[l&`7
count++; MK,#"Ty}zK
indexes = newint[count]; A=>%KQc?
for(int i = 0; i < count; i++){ (FP-
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indexes = pageSize * DdPU\ ZWR
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i; ;=aj)lemCr
} 2e#hJ-/`-
}else{ :D;BA
this.totalCount = 0; SK#;/fav6
} ELPzqBI
} o^H.uBO{
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publicint[] getIndexes(){ Nn>Oq+:
return indexes; l 'm!e '7_
} ZDMS:w.'T
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publicvoid setIndexes(int[] indexes){ 274F+X
this.indexes = indexes; "KSzn
} "K;f[&xO,o
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publicint getStartIndex(){ M*$#j|
return startIndex; 6C7|e00v
} I82GZL
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publicvoid setStartIndex(int startIndex){ <5BNcl\ZL
if(totalCount <= 0) b
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this.startIndex = 0; rU/8R'S
elseif(startIndex >= totalCount) B:oE&Ahh{
this.startIndex = indexes hX4V}kj
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[indexes.length - 1]; = Zi'L48
elseif(startIndex < 0) <Ukeq0
this.startIndex = 0; =/kwUjC?
else{ Qv1<)&Ft<
this.startIndex = indexes pd^"MG
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[startIndex / pageSize]; `?=Y^+*!-
} iewwL7
} c'md)nD2M
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publicint getNextIndex(){ NWue;u^
int nextIndex = getStartIndex() + ?LSwJ
@#
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pageSize; !(A<
if(nextIndex >= totalCount) _*wkTI+j
return getStartIndex(); s+0n0C
else bt'lT
return nextIndex; SiLWy=qbR
} C[R|@9NI
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publicint getPreviousIndex(){ Lrjp
int previousIndex = getStartIndex() - pN=>q<]L
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pageSize; 0JE*| CtK
if(previousIndex < 0) 7<0oK|~c#
return0; o)WzZ,\F^J
else ?Gx-q+H
return previousIndex; sW]>#e
} cC pNF `DN
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} =xjtPmZ5X
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抽象业务类 @rE+H
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java代码: "G!,gtA~
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/** ffy,ds_7
* Created on 2005-7-12 Um!LF"Z
*/ ^!6T,7B B
package com.javaeye.common.business; Wgm{
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import java.io.Serializable; E?h'OR@_ L
import java.util.List; 1`2lq~=GV
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import org.hibernate.Criteria; Ask~
import org.hibernate.HibernateException; \iH\N/
import org.hibernate.Session; QSx4M
import org.hibernate.criterion.DetachedCriteria; ua!RwSo
import org.hibernate.criterion.Projections; ]#\/1!W
import |?LUt@r;
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org.springframework.orm.hibernate3.HibernateCallback; :?$<:
import 9u1Fk'cxG,
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org.springframework.orm.hibernate3.support.HibernateDaoS a;v;% rs
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upport; 9R N ge;*
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import com.javaeye.common.util.PaginationSupport; i> PKE.
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public abstract class AbstractManager extends 7jPn6uz>w
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HibernateDaoSupport { *oru;=D@8
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privateboolean cacheQueries = false; Ip*[H#h
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privateString queryCacheRegion; oI9-jW
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publicvoid setCacheQueries(boolean K@@Jt
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cacheQueries){ hJGWa%`
this.cacheQueries = cacheQueries; }>m3V2>[
} "yPKdwP
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publicvoid setQueryCacheRegion(String aR0v qRF
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queryCacheRegion){ \\,z[C
this.queryCacheRegion = nXxSv~r
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queryCacheRegion; EhHW`
} hionR)R4
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publicvoid save(finalObject entity){
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getHibernateTemplate().save(entity); Tp%4{U/0`
} "6P- 0CJ
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); -QP&A >]7
} &Qq4xn+J
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publicvoid update(finalObject entity){ me/ae{
getHibernateTemplate().update(entity); s`"ALn8m
} IP+1 :M
pd
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publicvoid delete(finalObject entity){ LdY aJh~h
getHibernateTemplate().delete(entity); 7`6JK
} rFR2c?j8
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publicObject load(finalClass entity,
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Ss{
finalSerializable id){ QprzlxB
return getHibernateTemplate().load 'BwM{c-O"
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(entity, id); 2-M]!x)
} r.;(Kx/M
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publicObject get(finalClass entity, Ig6>+Mw
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finalSerializable id){ 5CuK\<
return getHibernateTemplate().get 5PlTf?Ao
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(entity, id); GQ8r5V4:
} U-EX)S^T[{
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publicList findAll(finalClass entity){ k6 f;A
return getHibernateTemplate().find("from #/9(^6f:
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" + entity.getName()); __V6TDehJ$
} k&P_ c
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publicList findByNamedQuery(finalString -j_J1P0,
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namedQuery){ ?y{C"w!
return getHibernateTemplate -zVa[&
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().findByNamedQuery(namedQuery); a;`-LOO5&
} :/IcFU~)M
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publicList findByNamedQuery(finalString query, 5i$~1ZC
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finalObject parameter){ u
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return getHibernateTemplate 0{Kl5>Z9M
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().findByNamedQuery(query, parameter); y+?tUSPP
} @X/S
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publicList findByNamedQuery(finalString query, k&DHQvfB
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finalObject[] parameters){ KW&&AuPb}
return getHibernateTemplate q'2PG@
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().findByNamedQuery(query, parameters); ),\>'{~5&
} @WEem(@
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publicList find(finalString query){ 4_N)1u !
return getHibernateTemplate().find n/8Kb.Vf
0 \LkJ*i
(query); Iv<9})2K
} p-i.ITRS
=!g/2;-or
publicList find(finalString query, finalObject fNAo$O4cm
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parameter){ y=oVUsG
return getHibernateTemplate().find nqurY62Ip
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(query, parameter); QWzOp\+
} C)J_lI{^
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public PaginationSupport findPageByCriteria ;e~{TkD
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(final DetachedCriteria detachedCriteria){ yUD_w
return findPageByCriteria 7z/(V\9B
r sX$fU8
(detachedCriteria, PaginationSupport.PAGESIZE, 0); SLQ\Y%F
} daA47`+d
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public PaginationSupport findPageByCriteria KJ0xp hf
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(final DetachedCriteria detachedCriteria, finalint :Wyn+
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startIndex){ nJtEUVMt
return findPageByCriteria [l8V<*x%S9
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(detachedCriteria, PaginationSupport.PAGESIZE, o~OwE7H)A
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startIndex); T:K"
} {h/OnBwG
] ?DDCew
public PaginationSupport findPageByCriteria qYgwyj=4
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(final DetachedCriteria detachedCriteria, finalint Zhzy.u/>
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pageSize, ,)h)5o(?
finalint startIndex){ Fc8E Y*
return(PaginationSupport) %9o+zg? RJ
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getHibernateTemplate().execute(new HibernateCallback(){ LmQ/#Gx
publicObject doInHibernate K;U39ofW
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(Session session)throws HibernateException { Z^zbWFO]5
Criteria criteria = RH(V^09[o
)`8pd 7<.
detachedCriteria.getExecutableCriteria(session); \dq!q=b\
int totalCount = ([ dT!B#aH
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((Integer) criteria.setProjection(Projections.rowCount nxaT.uFd1
by86zX
()).uniqueResult()).intValue(); 8~ #M{}
criteria.setProjection PJgp+u<
['[KR
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(null); 4:mCXP,x
List items = \M(*=5
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criteria.setFirstResult(startIndex).setMaxResults U,;xZe
:?CQuEv-
(pageSize).list(); k\N4@UK
PaginationSupport ps = ~]WVG@-
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new PaginationSupport(items, totalCount, pageSize, G>
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startIndex); C+%K6/J(
return ps; 0JY WrPR
} KJh,,xI>by
}, true); +.Bmkim
} %f&< wC
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public List findAllByCriteria(final /#S>sOg2xq
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DetachedCriteria detachedCriteria){ :b/jNHJU
return(List) getHibernateTemplate g4&jo_3:p
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().execute(new HibernateCallback(){ h`5)2n+ P
publicObject doInHibernate >dQ K.CG
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(Session session)throws HibernateException { ^Jx$t/t
Criteria criteria = i0pU!`0
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detachedCriteria.getExecutableCriteria(session); uDayBaR
return criteria.list(); .ve *Vp
} nr\q7
}, true); qpqokK
} HDIk9WC^
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public int getCountByCriteria(final q'S
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DetachedCriteria detachedCriteria){ %_gho
Integer count = (Integer) ?tYpc_p#
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getHibernateTemplate().execute(new HibernateCallback(){ Jb(Y,LO^
publicObject doInHibernate |4b)>8TL/
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(Session session)throws HibernateException { ?IYY'fS"
Criteria criteria = /-Qv?"
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detachedCriteria.getExecutableCriteria(session); Fhj8lVvk
return "="O >
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criteria.setProjection(Projections.rowCount uV]ULm#,i
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()).uniqueResult(); (#Mp 5C'X
} (> "QVxr
}, true); faJM^ u
return count.intValue(); f3PMVf:<
} rT7^-B*
} H;KDZO9W
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用户在web层构造查询条件detachedCriteria,和可选的 oXY Moi
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 YUkud2,j
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PaginationSupport的实例ps。 >Hwc,j
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ps.getItems()得到已分页好的结果集 zCe/Kukvy
ps.getIndexes()得到分页索引的数组 Fi;VDK(V9
ps.getTotalCount()得到总结果数 \cySWP[
ps.getStartIndex()当前分页索引 1;r69e
ps.getNextIndex()下一页索引 ;4~U,+Av
ps.getPreviousIndex()上一页索引 i g71/'D
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6`e@$(dfA
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Ill[]O
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一下代码重构了。 ]|Z b\{
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我把原本我的做法也提供出来供大家讨论吧: 3#GqmhqKDk
?9KGnOVu
首先,为了实现分页查询,我封装了一个Page类: =_d%=m
java代码: S%6U~@hig
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/*Created on 2005-4-14*/ ?p^2Z6J'$
package org.flyware.util.page; M?@pN<|
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/** b:MG@Hxc
* @author Joa D3]BTkMMS;
* [xaisXvI4
*/ 46XN3r
publicclass Page { 3Sh+u>w
ltA/
/** imply if the page has previous page */ l5O=VqCj
privateboolean hasPrePage; ]((i?{jb(
%$mjJw<|&
/** imply if the page has next page */ ;e{5)@h$
privateboolean hasNextPage; `E>vG-9
TSto9$}*
/** the number of every page */ Z9
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privateint everyPage; AK/:I>M
C1B'#F9EO
/** the total page number */ bBE+jqi2
privateint totalPage; F!g;A"?V
Ap<J'?~y
/** the number of current page */ p@I9<^"
privateint currentPage; y-+G
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/** the begin index of the records by the current ZKdh%8C
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query */ J!p<oW)a!
privateint beginIndex; !#WqA9<
`,#!C`E 9
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/** The default constructor */ Tov&68A~e
public Page(){ w|Qd`
T.Zz;2I
} dWpk='
jD9lz-Y@
/** construct the page by everyPage Tg''1 Wl*
* @param everyPage |uUuFm
* */ nNR:cGfG
public Page(int everyPage){ Yj8&
this.everyPage = everyPage; u,9q<&,
} Q[_Ni15
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/** The whole constructor */ ^k72{ 3N(
public Page(boolean hasPrePage, boolean hasNextPage, W"qL-KW
p":zrf'(6
-!R
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int everyPage, int totalPage, vLn> 4SK
int currentPage, int beginIndex){ ?5~!i9pY
this.hasPrePage = hasPrePage; VGJDqm!
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; 4#2 ,Y!
this.totalPage = totalPage; yq6LH
this.currentPage = currentPage; uUS)#qM|
this.beginIndex = beginIndex; Q8Te'1Ln!
} \=g!$
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/** .@K#U52
* @return CWMlZVG
* Returns the beginIndex. cx:jUsb6
*/ RKk"
publicint getBeginIndex(){ { _X#fq0}
return beginIndex; X[{\3Av
} bZ1 0v;
5KaSWw/
/** 8b~7~VCk
* @param beginIndex ~UW{)]_jox
* The beginIndex to set. 4K #^dJnC
*/ k4mTZ}6E
publicvoid setBeginIndex(int beginIndex){ }wL3mVz
this.beginIndex = beginIndex; h@Dw'w
} i*A$SJ:}
ee\Gl?VN
/** u[J7Y
* @return
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* Returns the currentPage. nOr"K;C
*/ 6\mC$: F
publicint getCurrentPage(){ c8\g"T
return currentPage; KM@`YV_"g
} 1Kc{#+a^
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/** W7]mfy^
* @param currentPage MHn&;
A]
* The currentPage to set. T/Ez*iQW
*/
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publicvoid setCurrentPage(int currentPage){ <H_LFrB$W
this.currentPage = currentPage; o"f%\N0_8
} rl41#6
i&5!9m`Cw
/** B8>FCF&}E
* @return 14;Av{Xt
* Returns the everyPage. G dL4|xv
*/ \O,j}O'
publicint getEveryPage(){ @US '{hO1p
return everyPage; ?({Pc F/
} +Hi{/{k0N
&a~L_`\'
/** 0sY#MHPT&
* @param everyPage BD?F`%-x
* The everyPage to set. [lrmuf
*/ v3!by N^
publicvoid setEveryPage(int everyPage){ '1qAZkz
this.everyPage = everyPage; >DkN+S
} Q=MCMe
R|6RI}
/** Sk!v,gx
* @return (#CBq
* Returns the hasNextPage. M_|M&lR>
*/ GF9ZL
publicboolean getHasNextPage(){ ?BXP}]
return hasNextPage; R,fMZHAG
} R4[. n@
n">?LN-DC
/** WX+< 4j
* @param hasNextPage (mu{~@Hw
* The hasNextPage to set. |F8;+nAVF#
*/ la!1[VeL
publicvoid setHasNextPage(boolean hasNextPage){ O1l4gduN|i
this.hasNextPage = hasNextPage; 'Sb6
w+
} ;mM\,
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/** r5X BcG(2
* @return ^*4(JR
* Returns the hasPrePage. h}c6+@w&-
*/ &T|UAM.
publicboolean getHasPrePage(){ &
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return hasPrePage; ta+"lM7A}$
} )BM WC
k
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/** ]h`E4B
* @param hasPrePage %WXVfkD
* The hasPrePage to set. sOrY^cY;
*/ !W6
publicvoid setHasPrePage(boolean hasPrePage){ `Q!FMv6Y^
this.hasPrePage = hasPrePage; BLYk
<m
} gE]a*TOZk
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/** |*| a~t
* @return Returns the totalPage. ![C$H5
*
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*/ t#{>y1[29
publicint getTotalPage(){ i*E`<9
return totalPage; &x5ZEe4
} c|a|z}(/J
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/** -H;y_^2
* @param totalPage I,uu>-
* The totalPage to set. r1?FH2Ns
*/ lR3^&d72?
publicvoid setTotalPage(int totalPage){ uzA'D ~)P
this.totalPage = totalPage; [|Pe'?zkf
} a<36`#N
==r|]~x
} oh)l\
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 `3n*4Lz
dz9-+C{m
个PageUtil,负责对Page对象进行构造: [63;8l}
java代码: &4FdA|9T
K)@Buu&,p
B.WkHY%/
/*Created on 2005-4-14*/ Q^Z}Y~.
package org.flyware.util.page; .AW*7Pp`f
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import org.apache.commons.logging.Log; 3%a37/|~y
import org.apache.commons.logging.LogFactory; RV(z>XM
PyF4uCn"H
/** 9F4|T7?
* @author Joa *xC '
* o$k$
*/ O~xmz!?=
publicclass PageUtil { #^V"=RbD
A UV$ S2
privatestaticfinal Log logger = LogFactory.getLog N|LVLsK
NR@Tj]`k
(PageUtil.class); %C:XzK-x
zl?N1>KS
/** es]m 6A
* Use the origin page to create a new page |i8dI )b
* @param page Dw3!
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* @param totalRecords [9^e
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* @return t_Wn<)XA
*/ G#v7-&Yl6
publicstatic Page createPage(Page page, int #!Fs[A5%
?Gfe?
totalRecords){ eX@q'Zi
return createPage(page.getEveryPage(), sSK$
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page.getCurrentPage(), totalRecords); Oa
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} 9=f'sqIPV
KRe=n3 1
/** ZP<X#]$qb
* the basic page utils not including exception 5ntP{p%>
]FBfh.#X@
handler 3!L)7Z/
* @param everyPage zOw]P6Gk
* @param currentPage 9Ba<'wk/>"
* @param totalRecords *1n:
* @return page c[$oR,2b13
*/ 0a'y\f:6*
publicstatic Page createPage(int everyPage, int \^cn}db)
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p?KJk)
currentPage, int totalRecords){ |&Q=9H*e
everyPage = getEveryPage(everyPage); o_n.,=/cZ
currentPage = getCurrentPage(currentPage); `h'^S,'*
int beginIndex = getBeginIndex(everyPage, <k!G%R<9
Yt^+31/%
currentPage); 9P$'ON'"
int totalPage = getTotalPage(everyPage, $7,dKC &
6>Y}2fT}o3
totalRecords); !l|Qyk[
boolean hasNextPage = hasNextPage(currentPage, #a&Vx&7L
dEiX!k$#
totalPage); q.7CPm+
boolean hasPrePage = hasPrePage(currentPage); ^5+-7+-S
~0NZx8qG
returnnew Page(hasPrePage, hasNextPage, ))N^)HR
everyPage, totalPage, n_<]9
currentPage, /Kvb$]F+!
h(sD] N
beginIndex); 9[!
Hz)|X
} V4H+m,R
m[pzu2R
privatestaticint getEveryPage(int everyPage){ or<JjTJ\o_
return everyPage == 0 ? 10 : everyPage; =bzTfki
} LtQy(F%8/
^cNP?7g7
privatestaticint getCurrentPage(int currentPage){ UgP5^3F2
return currentPage == 0 ? 1 : currentPage; ZS-9|EA<
} -~q]0>
/iK )tl|X
privatestaticint getBeginIndex(int everyPage, int yBoZ@9Do
jd{J3s '%
currentPage){ I2dt#
return(currentPage - 1) * everyPage; k[p
} uFqH_04
4Zq5
privatestaticint getTotalPage(int everyPage, int bQ)r8[o!
)mEF_ &
totalRecords){ 01Aa.i^d(
int totalPage = 0; QUNsS9
L*Y}pO
if(totalRecords % everyPage == 0) P'K')]D=!
totalPage = totalRecords / everyPage; 5v3B8 @CsA
else fq(e~Aqw$
totalPage = totalRecords / everyPage + 1 ; s)V^_@Z9
&jJgAZ!
return totalPage;
Oe27 3Y^e
} CUG6|qu
QZ6M,\
privatestaticboolean hasPrePage(int currentPage){ xQ[YQ!l
return currentPage == 1 ? false : true; x83XJFPWL
} #GF1MFkoS
82<L07fB
privatestaticboolean hasNextPage(int currentPage, ^uj+d"a)
Jx}5`{\
int totalPage){ 34U~7P
r9
return currentPage == totalPage || totalPage == =4I361oMf
, ^nUi c
0 ? false : true; Wp'\NFe8
} uC3$iY:_e
xv2;h4{<
:J"e{|g',
} 1$|z%(
uODsXi{z
'G^=>=w|Nv
>GcFk&x
'i,<j
s3\f
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。 NE! Xt <A
^v},Sa/ot]
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 &F:7U!
Frml'Vfq7
做法如下: fSTEZH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0L6L_;o
=19]a
的信息,和一个结果集List: 1a'JNe$
java代码: M}c_KFMV
~vXul`x
#?/.LMn{
/*Created on 2005-6-13*/ /i"EVN`t
package com.adt.bo; 7HF\)cz2
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H
import java.util.List; wEp/bR1=
VcP#/&B|
import org.flyware.util.page.Page; &dS+!<3
*be+x RY
/** jzV#%O{`
* @author Joa Vs"Z9p$U
*/ +]{X-R
publicclass Result { ] *Hz'
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private Page page; g(`6cY[}
K{iYp4pU
private List content; NubD2
Vg3&:g5 /
/** #4hP_Vhc
* The default constructor C{Zv.+F
*/ _#+9)*A
public Result(){ rfZA21y{?
super(); {> }U>V
} M]2 c-
[
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/** h~1QmEat
* The constructor using fields Oe`t!&v
* qS
al~
* @param page 4)I#[&f
* @param content ub5hX{uT
*/ u#~!%~
public Result(Page page, List content){ Ziimz}WHF
this.page = page; `@7tWX0
this.content = content; GwBQ
pNjy
} Z >=Y
s$x] fO
/** 9X9zIh]JV
* @return Returns the content. u7Y< ~
*/ ca3BJWY}J
publicList getContent(){ NQiecxvt=
return content; hf+/kc!>i
} 3^R] [;
fZV8o$V
/** CpRu*w{
* @return Returns the page. x"llX
*/ ?+,*YVT
public Page getPage(){ gUH'DS]{
return page; akvwApn5
} 9p\Hx#^
@6YBK+"
/** nl-t<#z[
* @param content %V <F<
* The content to set. ,;cel^.b
*/ j`|^s}8t
public void setContent(List content){ (O_t5<A*X
this.content = content; j*H;a ?Y
} XAU_SPAjiw
&ap`}^8pM
/** tf7v5iG e
* @param page 9oje`Ay
* The page to set. 3r-Vx P 5n
*/ J|"nwY}a9
publicvoid setPage(Page page){ fY%M=,t3c
this.page = page; (o*e<y,}W
} )+w/\~@
} 8yE%X!E
BA1MGh
~~xyFT+{F
xgtJl}L
Sqdc1zC
2. 编写业务逻辑接口,并实现它(UserManager, +24|_Lx0
Mm5U`mB
UserManagerImpl) >
h,y\uV1
java代码: 4/HY[FT
k(-Z@
A#Q0{z@H
/*Created on 2005-7-15*/ tKG;k"wk
package com.adt.service; \'; t*
7wiK.99
import net.sf.hibernate.HibernateException; RRS~ xOg
g,n-s+
import org.flyware.util.page.Page; ;Na8_}
u\()E|?p
import com.adt.bo.Result; TV1e
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C!ZI&cD9
/** i!SW?\
* @author Joa FylWbQU9
*/ 8^<c,!DM
publicinterface UserManager { /'&.aGW4%
eW%L$I
public Result listUser(Page page)throws CF3E]dt
69[V <1
HibernateException; wUZQB1$F
x1 ;rb8
} kf+JM/
q4sl=`L5Sp
6?%]odI#
lq>*x=<
0M#N=%31
java代码: ?vZWUWa
Jj=yG"$!
^H5w41
/*Created on 2005-7-15*/ b(q$j/~ zb
package com.adt.service.impl; Nl~Z,hT$*
F1 <489
import java.util.List; :0M'=~[
H{j~ihq7
import net.sf.hibernate.HibernateException; -]Q3/"Q
5"1!p3`\D{
import org.flyware.util.page.Page; 51&|t#8h
import org.flyware.util.page.PageUtil; 8_"3Yb`f
}Q`/K;yq
import com.adt.bo.Result; k k
8R
import com.adt.dao.UserDAO; fzLANya
import com.adt.exception.ObjectNotFoundException; o{9?:*?7
import com.adt.service.UserManager; nHI(V-E2:H
h^%GE;N
/** *mf}bTiS
* @author Joa AU0$A403
*/ _TZW|Dh-2F
publicclass UserManagerImpl implements UserManager { "I5uDFZR&
i%xI9BO9
private UserDAO userDAO; OF-E6b c
nped
/** M]J[6EW
* @param userDAO The userDAO to set. p9/bzT34.
*/ (d54C(")
publicvoid setUserDAO(UserDAO userDAO){ w|&,I4["
this.userDAO = userDAO; zXQVUhL6
} UE"7
''_,S,.a20
/* (non-Javadoc) 6e,Apj 0
* @see com.adt.service.UserManager#listUser d0'7efC+
O-i4_YdVt
(org.flyware.util.page.Page) u06tDJ[
*/ k&O C&
public Result listUser(Page page)throws Z/xV\Ggx
+z+F-
HibernateException, ObjectNotFoundException { mRwXN*Izw
int totalRecords = userDAO.getUserCount(); "PMO
if(totalRecords == 0) w"q-#,37j
throw new ObjectNotFoundException >g=^,G}y
6e*%\2UA
("userNotExist"); U> W|(Y
page = PageUtil.createPage(page, totalRecords); 5xhM0(
List users = userDAO.getUserByPage(page); Cm^Ylp
returnnew Result(page, users); T&]Na
} vxb@9eb!H
Dq|GQdZ>o
} YmOldR9v(
z3clUtC+
[9LxhPi
{JXf*IJ
?qy*s3j'M
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2v4W6R
1y7y0V
询,接下来编写UserDAO的代码: 18jJzYawh
3. UserDAO 和 UserDAOImpl: )5U!>,fT
java代码: OH>r[,z0
VDG|>#[!
)u<eO FI+
/*Created on 2005-7-15*/ F9%,MSt
package com.adt.dao; WXLK89ev\
P`tyBe#=
import java.util.List; pKq ]X}[^c
[O(m/
import org.flyware.util.page.Page; ,'u *ZB;
.wP/ai>}
import net.sf.hibernate.HibernateException; 7N|
AA^I
vmLpmxS
/** lirN YJ]tO
* @author Joa mf$Sa58
*/ q~j)W$k
publicinterface UserDAO extends BaseDAO { %Uf'+!4l`
##v`(#fu
publicList getUserByName(String name)throws Xo\S9,s{
1\y@E
HibernateException; `UQEXoB)
"T7>)fbu
publicint getUserCount()throws HibernateException; &sdx`,
68p R:
publicList getUserByPage(Page page)throws F{\=PCZ>7
=DC3a3&%
HibernateException; F 5U|9<
T<6GcI>A
} ?2ItTrlB
I|T7+{5z
o<rsAe
l
sr?b
!b63ik15O~
java代码: BPewc9RxV
`;cz;"
{[P!$
/
/*Created on 2005-7-15*/ {E~Xd
package com.adt.dao.impl; CdL.?^
nmg{%P
import java.util.List; N2Ssf$
(hN?:q?'
import org.flyware.util.page.Page; (v^Z BM_
ke]Yfwk
import net.sf.hibernate.HibernateException; n}OU Y
import net.sf.hibernate.Query; kC`Rd:5
~b6GrY"vB
import com.adt.dao.UserDAO; (A4&k{C_
+GeWg`
\=
/** Y{+3}drJE
* @author Joa ]]PE#DDg
*/ oj@g2H5P
public class UserDAOImpl extends BaseDAOHibernateImpl fEwifSp.
,H{={aln
implements UserDAO { UP8{5fx'
l!@ 1u^v2
/* (non-Javadoc) "V}qf3qU
* @see com.adt.dao.UserDAO#getUserByName AY88h$a
EEwWucQ
(java.lang.String) r6
}_H?j
*/ m9t$h
publicList getUserByName(String name)throws ]0-<>
q3+8]-9|5
HibernateException { T5e^J"
String querySentence = "FROM user in class 5v|EAjB6o
u"Y]P*[k
com.adt.po.User WHERE user.name=:name"; ;;Tq$#vd
Query query = getSession().createQuery %/pc=i|+
B}\BeFt'
(querySentence); m\-PU z&C
query.setParameter("name", name); V3uXan_
return query.list(); X"<|Z]w
} ~ffwLgu!
p6[ (81
/* (non-Javadoc) }_%P6
* @see com.adt.dao.UserDAO#getUserCount() "+h/-2rA
*/ nzuF]vo
publicint getUserCount()throws HibernateException { ,LUTHWEo"I
int count = 0; "%
Y u
wMY
String querySentence = "SELECT count(*) FROM j^EbO3
0( //D;j
user in class com.adt.po.User"; [W;[v<E;
Query query = getSession().createQuery BS2?!;,8
PGX+p+wB
(querySentence); S#2[%o
count = ((Integer)query.iterate().next z<<Tk.65
vr4S9`,
()).intValue(); L|\Diap
return count; O-!,Jm
} ],&\%jd<
Zi4d]
/* (non-Javadoc) U
~1SF
* @see com.adt.dao.UserDAO#getUserByPage \ja `c)x
o;QZe&
(org.flyware.util.page.Page) - 9-fX(I
*/ o0`q#>7!_b
publicList getUserByPage(Page page)throws Pz`hX$
hk;bk?:m
HibernateException { r0btC@Hxy
String querySentence = "FROM user in class W4vBf^eC
o](.368+4
com.adt.po.User"; )4uq
iA6
Query query = getSession().createQuery woau'7}XOu
c[5@\j\
(querySentence); ML=z<u+
query.setFirstResult(page.getBeginIndex()) zs8I
.setMaxResults(page.getEveryPage()); =P]GPEz_
return query.list(); =]b9X7}
} 40.AM1Z0f
O<X
)p`,`
} 5i9Ub|!P
2AK}D%jfc
kqf8=y
^PQM;"
yjpz_<7a=
至此,一个完整的分页程序完成。前台的只需要调用 -tyaE
xJc.pvVPw
userManager.listUser(page)即可得到一个Page对象和结果集对象 *"T+G*~
0jTMZ<&zZ
的综合体,而传入的参数page对象则可以由前台传入,如果用 jY+Do:#/wO
J6auUm` `
webwork,甚至可以直接在配置文件中指定。 !.eAOuq
Hirr=a3
下面给出一个webwork调用示例:
V16%Ne
java代码: ccMd/
hBy*09Sv
Zs73
ad
/*Created on 2005-6-17*/ e~
BJvZ}Q
package com.adt.action.user; 24X=5Aj
m1y `v"
import java.util.List; *h:D|4oJ(
<8*A\&
import org.apache.commons.logging.Log; }|SIHz!R
import org.apache.commons.logging.LogFactory; 08<k'Oi]
import org.flyware.util.page.Page; F Q8RK~?`
v7s]
import com.adt.bo.Result; qZT 4+&y
import com.adt.service.UserService; 4+ASwN9
import com.opensymphony.xwork.Action; CL)1Q
zjluX\
/** 8zP:*|D
* @author Joa 6{JR 0
*/ OaD
Alrm
publicclass ListUser implementsAction{ Cfv L)f
_hAj2%SL
privatestaticfinal Log logger = LogFactory.getLog p`E|SNt/W
Mr5('9%
(ListUser.class); $d??(
HS&uQc a
private UserService userService; r0$9c
5tCq}]q#P
private Page page; 7!yF5+_d
!VZCM{
privateList users; Nm:<rI,^
9kg>)ty@
/* f}d@G/L
* (non-Javadoc) e.h:9`"*
* ee\zU~
* @see com.opensymphony.xwork.Action#execute() $$>,2^qr&L
*/ *xKR;?.
publicString execute()throwsException{ ZXkAw sr
Result result = userService.listUser(page); 0+h?Bk
page = result.getPage(); KwyXM9h6=
users = result.getContent(); J(L$pIM
return SUCCESS; 3P>@ :
} 3F3?be
Pr"ESd>Y
/** FeJ5^Gh.
* @return Returns the page. sy?W\(x
*/ hCrgN?Mz
public Page getPage(){ hR2.w/2j
return page; O5w\oDhMb
} 3m'6 cMQ
'tj4 ;+xf^
/** w6tY6bf}
* @return Returns the users. wO9<An
*/ O)?0G$0
publicList getUsers(){ bE{`g]C5
return users; rkrt.B
}
u[u=:Y+
wKN9HT
/** {_JLmyaerZ
* @param page xHmc8G$zu
* The page to set. }\ F>z
*/ 3ml|`S
publicvoid setPage(Page page){ aap:~F{]X
this.page = page; !WmpnPr1
} A@4Cfb@
!
^W|;bq
/** w K+2;*bI
* @param users ME(!xI//JZ
* The users to set. VmW_,
*/ #rC% \
publicvoid setUsers(List users){ Jg:'gF]jt
this.users = users; :5(TOF
} ETIf x)B-
z"-Urd^O
/** j(SQNSFD
* @param userService 6\bbP>ql
* The userService to set. qy!G&
*/ ]3v
publicvoid setUserService(UserService userService){ _ n>0!
this.userService = userService; {>:2Ff]O:
} ^a]:GPc
} .F]6uXd
{|fA{ Q_R
LRs{nN.N
4DNZ y2`
,W#y7t
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, mb#)w`<
i|<*EXB"
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 $6_J`7
q*T+8O
么只需要: Deam%)bXM]
java代码: eRf8'-"#-
6};Sn/8
TiOvrp7B
<?xml version="1.0"?> T57S!CJ^$5
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [~J4:yDd=
:( `Q4D~l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Lpn`HAw&
(<f[$ |%
1.0.dtd"> )a.U|[:y[+
`pKQ|zGw
<xwork> i^n&K:6
{ d/k0H
<package name="user" extends="webwork- q3;HfZ
"e(Nh%t
interceptors"> JsH9IK:
?e BN_a,r6
<!-- The default interceptor stack name 7~IAgjo,@
`527vK
6
--> |ey6Czm
<default-interceptor-ref LOQEU?z
eX=W+&lj
name="myDefaultWebStack"/> 2nwP-i
rc$G0O
<action name="listUser" :+u?A
ub-ZrC'
class="com.adt.action.user.ListUser"> Y+D#Dv |
<param O*30|[
x1TB
(^aX
name="page.everyPage">10</param> s]}P
jh8
<result 3.8d"
:#+VH_%N
name="success">/user/user_list.jsp</result> rHP5;j<]
</action> ,3x3&c
&