Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 c=re(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T%E/k#
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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 :bkmm,%O
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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 J^zB5W,)
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分页支持类: u.}H)wt
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java代码: (Mw+SM3<
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package com.javaeye.common.util; NzS`s,N4/0
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import java.util.List; ]$U A5/a
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publicclass PaginationSupport { UDPn4q
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publicfinalstaticint PAGESIZE = 30; W*2P+H%
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privateint pageSize = PAGESIZE; 4r#4h4`y|
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privateList items; TV/ EC#48
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privateint totalCount; whFJ]
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privateint[] indexes = newint[0]; Xm<|m#
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privateint startIndex = 0; sAnb
}(K1=cEaL
public PaginationSupport(List items, int &d]@$4u$;
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totalCount){ |Z8Eu0RSb
setPageSize(PAGESIZE); (IIZ vCek
setTotalCount(totalCount); &g]s@S|%
setItems(items); =&m;5R
setStartIndex(0); [EK@f,iM
} 83VFBY2q
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public PaginationSupport(List items, int Q'YakEv >=
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totalCount, int startIndex){ Ql"~ z^L
setPageSize(PAGESIZE); 5yjG\~
setTotalCount(totalCount); szD9z{9"y
setItems(items); WwUHHm<v
setStartIndex(startIndex); u1>WG?/`
} b&'YW*W
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public PaginationSupport(List items, int )"_&CYnd
fr}.#~{5Y
totalCount, int pageSize, int startIndex){ y[GqV_~?Y
setPageSize(pageSize); t+M'05-U2
setTotalCount(totalCount); ;O~%y'
setItems(items); @?gRWH;Pq
setStartIndex(startIndex); b"Jr_24t3v
} QQD7NN>
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publicList getItems(){ i?,\>LTG
return items; .R^ R|<x
} iu2O/l#r
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publicvoid setItems(List items){ :k2J
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this.items = items; 0qm CIcg
} h-U]?De5\
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publicint getPageSize(){ Y Azj>c&
return pageSize; 'Z)#Sz Y
} 8!MVDp[|"
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publicvoid setPageSize(int pageSize){ -fN5-AC
this.pageSize = pageSize; 40[@d
} 0a1Mu>P,
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publicint getTotalCount(){ fS p
return totalCount; 2>f3nW
} W*/2x8$d
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publicvoid setTotalCount(int totalCount){
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if(totalCount > 0){ <RcB: h
this.totalCount = totalCount; ?QtM|e
int count = totalCount / ]C{N4Ni^Z
.N7&Jy
pageSize; 7^1K4%IPl
if(totalCount % pageSize > 0) t0Inf
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count++; |nU%H=Rs/
indexes = newint[count]; t{`uN
for(int i = 0; i < count; i++){ Jgy6 !qUn_
indexes = pageSize * r4fd@<=g
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i; ;u<F,o(
} Swgvj(y;!A
}else{ V7vojm4O
this.totalCount = 0; ]#7baZ
} vzF6e eaD
} Q |hBGH9:B
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publicint[] getIndexes(){ :*-O;Yw?S@
return indexes; !uA'0U?ky
} {mLv?"M]
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publicvoid setIndexes(int[] indexes){ i_nUyH%b
this.indexes = indexes; fc4jbPp:M
} +e#(p<
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publicint getStartIndex(){ ?"kU+tCxg
return startIndex; =@nW;PUZ
} G0Z$p6z
@P h'!
publicvoid setStartIndex(int startIndex){ ]qx!51S
if(totalCount <= 0) ^;$9>yi1
this.startIndex = 0; v7v>
elseif(startIndex >= totalCount) C;ME"4,(
this.startIndex = indexes |w -s{L3@+
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[indexes.length - 1]; nN>Uh T
elseif(startIndex < 0) 2#8PM-3"
this.startIndex = 0; T0 cm+|S
else{ [hqat'Vj,
this.startIndex = indexes n.,ZgLx["
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[startIndex / pageSize]; ^c"\%!w"O
} Psm9hP :m
} |T-Ytuy8
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publicint getNextIndex(){ m"o=R\C
int nextIndex = getStartIndex() + Mb97S]878I
cca]@Ox]
pageSize; ;a[3RqmKW
if(nextIndex >= totalCount) [geT u
return getStartIndex(); |7.X)h`
else ncpA\E;ff^
return nextIndex; w)h"?'m~
} K
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publicint getPreviousIndex(){ 6!){-IV
int previousIndex = getStartIndex() - J+`gr_&
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pageSize; CljEC1S#
if(previousIndex < 0) [TT:^F(Y
return0; $GVf;M2*
else
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return previousIndex;
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} WK.,q>#
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} !H @nAz
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抽象业务类 Mi`t$hmP
java代码: E.yc"|n7l2
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/** avqJ[R
* Created on 2005-7-12 }~#qDrK
*/ s3~6[T?8
package com.javaeye.common.business; ])WIw'L!
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import java.io.Serializable; XLm@, A[
import java.util.List; " j:15m5
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import org.hibernate.Criteria; ^AO2%09.S
import org.hibernate.HibernateException; xCMuq9zt@
import org.hibernate.Session; C+gu'hD
import org.hibernate.criterion.DetachedCriteria; 1i Q(q\%
import org.hibernate.criterion.Projections; 5zt5]zl'
import l_2YPon
h5))D!
org.springframework.orm.hibernate3.HibernateCallback; +:z%#D
import y|WOw(#
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org.springframework.orm.hibernate3.support.HibernateDaoS P?y{9H*
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upport; eh3CVgH91;
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import com.javaeye.common.util.PaginationSupport; a0
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public abstract class AbstractManager extends {dV!sQD
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HibernateDaoSupport { M5S<N_+Pe
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privateboolean cacheQueries = false; ~ o5h}OU"
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privateString queryCacheRegion; );^{;fLy%
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publicvoid setCacheQueries(boolean ||4++84{
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cacheQueries){ [_p&,$z8[
this.cacheQueries = cacheQueries; DzY`O@D[
} s06R~P4
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publicvoid setQueryCacheRegion(String iHyA;'!Os
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queryCacheRegion){ 3.
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this.queryCacheRegion = j<i:rk|
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queryCacheRegion; bJ6v5YA%
} GZ"J6/0-|
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publicvoid save(finalObject entity){ hfQ^C6yR
getHibernateTemplate().save(entity); wW^3/
} C#.d
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publicvoid persist(finalObject entity){ 1
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getHibernateTemplate().save(entity); No)@#^
} f@IL2DL}\
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publicvoid update(finalObject entity){ :*lB86Ly
getHibernateTemplate().update(entity); -Cf<
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} YZ+<+`Mz<
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publicvoid delete(finalObject entity){ 4_?*@L1
getHibernateTemplate().delete(entity); j'FBt8P'
} skfFj&_T
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publicObject load(finalClass entity, ZlYb8+rW
3)qtz_,H/g
finalSerializable id){ ]i:O+t/U
return getHibernateTemplate().load C)Hb=
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(entity, id); `LCxxpHi|
} LgS.%Mn
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publicObject get(finalClass entity, .;9I:YB$
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finalSerializable id){ V9kL\Ys
return getHibernateTemplate().get dg42K`E
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(entity, id); _p=O*$b.
} K)t+lJ
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publicList findAll(finalClass entity){ C$$lJ=>
return getHibernateTemplate().find("from [z`m`9Aq
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" + entity.getName()); vc(6lN9>
} *1;}c
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publicList findByNamedQuery(finalString nA^UF_rD-
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namedQuery){ {EGm6WSQ^
return getHibernateTemplate uia-w^F e
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().findByNamedQuery(namedQuery); n,NKJt
} O
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publicList findByNamedQuery(finalString query, ^++ec>
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finalObject parameter){ .pQ4#AJ
return getHibernateTemplate &llp*<
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().findByNamedQuery(query, parameter); Af>Ho"i
} `$D2w|
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publicList findByNamedQuery(finalString query, 3YF*TxKx
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finalObject[] parameters){
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return getHibernateTemplate CCZ]`*wJ
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().findByNamedQuery(query, parameters); we&g9j'
} ,kKMUshBi
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publicList find(finalString query){ JY tM1d
return getHibernateTemplate().find }
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(query); (s`yMUC+
} /a$RJ6t&3
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publicList find(finalString query, finalObject |PED8K:rU
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parameter){ :jq
return getHibernateTemplate().find DKfw8"L]
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(query, parameter); +[
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} ggUJ -M'2h
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public PaginationSupport findPageByCriteria j6KGri
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(final DetachedCriteria detachedCriteria){ cO"7wgg
return findPageByCriteria ;Qc_Tf=,
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); T)ra>r<#
} J34lu{'if
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public PaginationSupport findPageByCriteria 6 ztM(2[
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(final DetachedCriteria detachedCriteria, finalint T&=1IoOg
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startIndex){
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return findPageByCriteria MhZT<6
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(detachedCriteria, PaginationSupport.PAGESIZE, F$FCfP7
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startIndex); (:>:tcE
} ||&EmH
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public PaginationSupport findPageByCriteria 7)NQK9~
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(final DetachedCriteria detachedCriteria, finalint 4#Fz!Km
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pageSize, KF|<A@V
finalint startIndex){ UNJ]$x0
return(PaginationSupport) x62b=k}
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getHibernateTemplate().execute(new HibernateCallback(){ zM^ux!T=
publicObject doInHibernate zR_#c3o
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(Session session)throws HibernateException { D^Bd>Ey4
Criteria criteria = A`4j=OF\
BOLG#}sm
detachedCriteria.getExecutableCriteria(session); 9i8D_[
int totalCount = D84`#Xbi
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((Integer) criteria.setProjection(Projections.rowCount wY2#xD
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()).uniqueResult()).intValue(); YB h:
criteria.setProjection )Aa98Eu?2
{4g1Wr5=
(null); n_%JXm#\
List items = zF'{{7o
+%G*)8N3
criteria.setFirstResult(startIndex).setMaxResults %QUV351H
HPAd@5d(
(pageSize).list(); ) w.cCDL c
PaginationSupport ps = N?H;fK4v
/I3#WUc;![
new PaginationSupport(items, totalCount, pageSize, MC!K7ji
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startIndex); iq
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return ps;
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} :Xv3< rS<
}, true); mfO:#]K
} zm}4=Kz}
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public List findAllByCriteria(final _^'fp
R ;^[4<&
DetachedCriteria detachedCriteria){ R/M:~h~F!
return(List) getHibernateTemplate twqjaFA>
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().execute(new HibernateCallback(){ nn"!x|c
publicObject doInHibernate
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(Session session)throws HibernateException { <L@0w8i`
Criteria criteria = v6
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Rx*T7*xg{
detachedCriteria.getExecutableCriteria(session); L=Q-r[
return criteria.list(); 9}Tf9>qP>M
} '2a }1?
}, true); o_p//S#q
} _cx}e!BK#
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public int getCountByCriteria(final >~I~!i3
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DetachedCriteria detachedCriteria){ F8?&Ql/hdz
Integer count = (Integer) gEtDqq~y@
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getHibernateTemplate().execute(new HibernateCallback(){ *TA${$K
publicObject doInHibernate E27wxMU
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(Session session)throws HibernateException { ~zFs/(k
Criteria criteria = Zgo^M,g
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detachedCriteria.getExecutableCriteria(session); vbmSbZ"y
return fR}|CP
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criteria.setProjection(Projections.rowCount _r5Q%8J
Gd`qZqx#
()).uniqueResult(); )JTh=w4n|z
} d:O>--$_tw
}, true); ;Br8\2=$
return count.intValue(); kssS,Ogf\_
} zv!%u=49
} $BG4M?Y
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用户在web层构造查询条件detachedCriteria,和可选的 Lw?4xerLsb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ErJi
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PaginationSupport的实例ps。 &}VGC=F;d
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ps.getItems()得到已分页好的结果集 %xf6U>T
ps.getIndexes()得到分页索引的数组 oJR0sbikP
ps.getTotalCount()得到总结果数 }8p;w T!
ps.getStartIndex()当前分页索引 ~" B0P>7
ps.getNextIndex()下一页索引 xA#B1qbw
ps.getPreviousIndex()上一页索引 4hg]/X"H#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 D|,d_W
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 j/{F#auI
oA}&o_Q%
一下代码重构了。 b~
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我把原本我的做法也提供出来供大家讨论吧: /K:M
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首先,为了实现分页查询,我封装了一个Page类: JSt%L|}Y
java代码: |dpOE<f[
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/*Created on 2005-4-14*/ rv1kIc5Za<
package org.flyware.util.page; <)n1Z[4
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/** }XWic88!~
* @author Joa /}-]n81m
* BbA>1#i5]
*/ Cp&lS=
publicclass Page { aAF:nyV~~0
F*o{dLJ)
/** imply if the page has previous page */ #IA[erf:
privateboolean hasPrePage; CtV$lXxup
^.&uYF&
/** imply if the page has next page */ uO>$,s
privateboolean hasNextPage; C[gCwDwl
cPi 3UjY~
/** the number of every page */ XgP7
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privateint everyPage; THWT\3~,
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/** the total page number */ 1`r
4
privateint totalPage; [Pi8gj*
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/** the number of current page */ ?ah-x""Y
privateint currentPage; u1/4WYJeJ
:h=];^/E
/** the begin index of the records by the current 2)h
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query */ NZ/gp"D?
privateint beginIndex; F(^vD_G
oqB(l[%z2
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/** The default constructor */ _W/s=pCh
public Page(){ fySzZ
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} VmHok
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/** construct the page by everyPage |3/=dG
* @param everyPage
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* */ .slA}
public Page(int everyPage){ z*>"I
this.everyPage = everyPage; SN(:\|f
2
} k q8:h
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/** The whole constructor */ Oj\lg2Ck
public Page(boolean hasPrePage, boolean hasNextPage, 2HoTj|
tm @&f
L
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int everyPage, int totalPage, [0El z@.C
int currentPage, int beginIndex){ 6C4c.+S
this.hasPrePage = hasPrePage; C$SuFL(pb
this.hasNextPage = hasNextPage; AIR,XlD
this.everyPage = everyPage; {3@f(H m
this.totalPage = totalPage; v{$X2z_$w
this.currentPage = currentPage; /qed_w.p
this.beginIndex = beginIndex; 57* z0<
} #Gx%PQ`
QxH%4 )?
/** R22YKXU
* @return fPZt*A__
* Returns the beginIndex. 0z #'=XWk
*/ )."_i64
publicint getBeginIndex(){ 6x)7=_:0
return beginIndex; P {i\x#
} M' e<\wqm
m.pB]yq&
/** f
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* @param beginIndex %B}Q .'
* The beginIndex to set. ~ P"@^cq
*/ 6O
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publicvoid setBeginIndex(int beginIndex){ &YGd!Q
this.beginIndex = beginIndex; ;e415T
} 9+nB;vA
m~'!
/** Yrs7F.Y"
* @return aY}:9qBice
* Returns the currentPage. )=;GQ*<8Zs
*/ Wf/r@/q
publicint getCurrentPage(){ f_Ma~'3
return currentPage; dKTyh:_{
} 3p6QJuSB
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/** f(:+JH<P~
* @param currentPage 'i;1n
* The currentPage to set. 6=U81
*/ y$|%K3
publicvoid setCurrentPage(int currentPage){ kd)Q$RA(
this.currentPage = currentPage; >lQ@" U
} c[J?`8
gI "ZhYI
/** 4l7TrCB
* @return bc=,$
* Returns the everyPage. g5M=$y/H
*/ $s+/OgG4H
publicint getEveryPage(){ yiO!ZT
return everyPage; dv-L!C
} M<^]Ywq*p
7aRtw:PQn
/** fqrQ1{%UH
* @param everyPage ?g^42IYG
* The everyPage to set. =!)Ye:\Q
*/ )UbPG`x8
publicvoid setEveryPage(int everyPage){ TwlX'iI_;
this.everyPage = everyPage; vT~ey
} i)y8MlC{
3n;>k9{
/** ]xC#XYE:dy
* @return w\,N}'G
* Returns the hasNextPage. ]<L(r,@,
*/ d-c<dS+R
publicboolean getHasNextPage(){ /N= }wC
return hasNextPage; ${m;x: '
} V5:ad
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/** 60,z! Vv
* @param hasNextPage T<yAfnTb`
* The hasNextPage to set. X-LCIT|1
*/ /By:S/[1pL
publicvoid setHasNextPage(boolean hasNextPage){ Lh%z2 5t
this.hasNextPage = hasNextPage; WoM;) Q
} -]el_:H
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/** %"-bG'Yc
* @return <G|i!Pm
* Returns the hasPrePage. j5m KJC
*/ !q\MXS($#u
publicboolean getHasPrePage(){ ]QKo>7%[
return hasPrePage; A,67)li3
} -Zq\x'
-yOwX2Wv5;
/** b S-o86u
* @param hasPrePage bGw56s'R5~
* The hasPrePage to set. ` _aX>fw
*/ ICck 0S!
publicvoid setHasPrePage(boolean hasPrePage){ A0hKzj
this.hasPrePage = hasPrePage; 6$CwH!42F
} :I_p4S.)
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/** '41'Gn
* @return Returns the totalPage. .3
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* |w5m2Z
*/ S[ch/
publicint getTotalPage(){ L~oy|K67
return totalPage; "<Ozoo1&w
} &!P' M
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/** 6/Iq@BZ&
* @param totalPage 0N;~(Vt2
* The totalPage to set. Z(j"\d!y
*/ Hlhd6be
publicvoid setTotalPage(int totalPage){ }NjZfBQW`
this.totalPage = totalPage; o|:c{pwq
} n%|og^\0
PRJ
} 8[b_E5!V
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[ Y+Ta,
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 !3F3E8%
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个PageUtil,负责对Page对象进行构造: {W+IUvn
java代码: vf&_
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/*Created on 2005-4-14*/ QC,fyw\
package org.flyware.util.page; x~Y{
{
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import org.apache.commons.logging.Log; 'C4cS[1
import org.apache.commons.logging.LogFactory; LBxmozT
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/** `j1oxJm
* @author Joa azz=,^U#
* <%o9*)F
*/ dGyrzuPJ
publicclass PageUtil { D@2L<!\
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privatestaticfinal Log logger = LogFactory.getLog 1=Z!ZY}}e
3Ccy %;
(PageUtil.class); InI>So%e|<
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/** }u9#S
* Use the origin page to create a new page ?g\emhG
* @param page Nq9\ 2p
* @param totalRecords m"@o
* @return nU4to
*/ h1t~hrq
publicstatic Page createPage(Page page, int 3k3C\Cw
6r|=^3{
totalRecords){ W#)X@TlE
return createPage(page.getEveryPage(), F r!FV4
-MRX@ a^1
page.getCurrentPage(), totalRecords); 5JHWt<n{P
} V/3@iOwD
7u{V1_n1
/** qnCjNN
* the basic page utils not including exception WBD?|Ss
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handler @R-11wP)M
* @param everyPage T>f6V 5
* @param currentPage Ol B9z
* @param totalRecords b'``0OB )
* @return page z&cM8w:
*/ 7Db}bDU1
|
publicstatic Page createPage(int everyPage, int Jd^Lnp6?
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currentPage, int totalRecords){ iC3C~?,7
everyPage = getEveryPage(everyPage); |Fz ^(US
currentPage = getCurrentPage(currentPage); [^Bjmw[7
int beginIndex = getBeginIndex(everyPage, ?&'Kw>s@
O\CnKNk,
currentPage); Y[l<fbh(}
int totalPage = getTotalPage(everyPage, ue^HhZ9
GE`1j'^-
totalRecords); N]eBmv$|
boolean hasNextPage = hasNextPage(currentPage, 3&>0'h
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totalPage); 2}=@n*8*d
boolean hasPrePage = hasPrePage(currentPage); C1'y6{,@
{,i-V57-h
returnnew Page(hasPrePage, hasNextPage, l$1NI#&
everyPage, totalPage, ZNne 8
currentPage, /vq$/
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beginIndex); P1AC2<H
} XUzOt_L5<
p^|6 /b
privatestaticint getEveryPage(int everyPage){ wZZ~!"O&
return everyPage == 0 ? 10 : everyPage; N8pV[\f
} .XqeO@z
HMC-^4\%[
privatestaticint getCurrentPage(int currentPage){ =n5n
return currentPage == 0 ? 1 : currentPage; _Dd>e=v
} #|4G,!
=\_gT=tZ
privatestaticint getBeginIndex(int everyPage, int m%
3 D
7Q]c=i cg
currentPage){ `LNhamp
return(currentPage - 1) * everyPage; "w$,`M?2
} ?m5EXe
*L9v(Kc
privatestaticint getTotalPage(int everyPage, int ~|9VVeE
#CPLvg#
totalRecords){ 7UY4* j|[C
int totalPage = 0; 5[g\.yi2_]
' Ut4=@)
if(totalRecords % everyPage == 0) )
[?xT
totalPage = totalRecords / everyPage; }NoP(&ebz*
else hf]m'5pb
totalPage = totalRecords / everyPage + 1 ; .b+ix=:
SkMFJ?J/
return totalPage; 4w~%MZA^
} p J_+n:_{
~uH_y-
privatestaticboolean hasPrePage(int currentPage){ 04jvrde8-O
return currentPage == 1 ? false : true; yq49fEgc@U
} 'AX5V-t
8 eK 8-R$
privatestaticboolean hasNextPage(int currentPage, $&&E[JY
Yb-{+H8{J
int totalPage){ f+Acs*.GQ
return currentPage == totalPage || totalPage == X3a 9-
#gqh0 27
0 ? false : true; m0As t<u
} zxx\jpBBk
xI1{Wo*2C}
c\2rKqFD8
} n8F~!|lQ0
k'PvTWR
4")`}T
2?GMKd)
?"r=08
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 3r,~-6
'St6a*
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 )PTvw>
ZaU8eg7
做法如下: k`Ifl)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >9rZVNMU
}a$.ngP
的信息,和一个结果集List:
>iae2W`
java代码: g&c ~grD
{='Bd6_=
5gtf`ebs/
/*Created on 2005-6-13*/ e~'lWJD
package com.adt.bo; gT_KOO0n
<BED&j!qvP
import java.util.List; _ Lb"yug
.dk<?BI#H
import org.flyware.util.page.Page; Hl0"
zS[
IO)#O<
/** .a]#AFX
* @author Joa >i,_qe?V:w
*/ z'"7zLQ
publicclass Result { ,JE_aje7
'1:) q
private Page page;
k[D_L`
@wgd
3BU
private List content; Si>38vCJ*
(tX3?[ii
/** X}v*"`@Q
* The default constructor ^~;ia7V&2
*/ %`yfi+e
public Result(){ IibrZ/n6
super(); m4 (pMrJ
} G n]qh(N>
uqC#h,~
0
/** PlGif)
* The constructor using fields D#b*M)X"
* -!Myw&*\V
* @param page J+`aj8_ B
* @param content ;Zd_2CZ
*/ /RxP:>hVv
public Result(Page page, List content){ 25)9R^
this.page = page; _-TplGSO=c
this.content = content; TU0-L35P1
} WFOJg&
x,,y}_YX
/** Io]FDPN
* @return Returns the content. V.P<>~W
*/ TlS? S+
publicList getContent(){ 1.cP3kl
return content; a/j;1xcc<
} F3}MM
dX
{h?pvH_>
/** s$R /!,c
* @return Returns the page. /l*v *tl
*/ G%erh}0~
public Page getPage(){ R+M =)Z
return page; g#J aw|N
} 35& ^spb
a{]=BY oL
/** \X8b!41
* @param content *y*tI}
* The content to set. zFq%[ X
*/ !4vb{AH
public void setContent(List content){ VGV-t
this.content = content; 4!/JN J
} UphTMyn3
y|5s
/** r)iEtT!p*
* @param page 2tq2
* The page to set. uQ5h5Cfz
*/ -F ~DOG%
publicvoid setPage(Page page){ ;5 j|B|v
this.page = page; %":3xj'EEI
} r<UVO$N
} AHb_B gOU*
VL9wRu;
{]HiT pn
_Op%H)
JI"/,fK^
2. 编写业务逻辑接口,并实现它(UserManager, NKO"'
}`"}eN @,
UserManagerImpl) 0^ODJ7
java代码: j<t3bM-G
: ,l7e
a: "1LnvR
/*Created on 2005-7-15*/ SyvoN,;Q
package com.adt.service; F^yW3|Sb
l_^OdQ9D
import net.sf.hibernate.HibernateException; =0)|psCsM
mTE(JZt
import org.flyware.util.page.Page; DK IH{:L7
F0:]@0>r
import com.adt.bo.Result; aA`eKy) \
J2=4%#R!
/** l 00i2w
* @author Joa GcVQz[E
*/ ]8p{A#1
publicinterface UserManager { b>07t!;
f7=MgFi
public Result listUser(Page page)throws y]j.PT`Cw
YN8x|DLi?
HibernateException; Mn0.!J
"
tIuM9D{P
} *2/Jg'de
axC|,8~tq
Z=JKBoAY
1sqE/-v1_^
P(D>4/f3"
java代码: %B%_[<B
LZykc
c9g
OyTK,i<n
/*Created on 2005-7-15*/ -r\jIO_
package com.adt.service.impl; +4?Lwp'q
{iD/0q
import java.util.List; <]rayUyaf
l/N<'T_G
import net.sf.hibernate.HibernateException; ZJ/528Ju
J>Ar(p
import org.flyware.util.page.Page; LDt6<D8,Q
import org.flyware.util.page.PageUtil; A,~3oQV
B7%,D}
import com.adt.bo.Result; FuHBzBoM=
import com.adt.dao.UserDAO; %ih\|jRt
import com.adt.exception.ObjectNotFoundException; >]h{[kU %4
import com.adt.service.UserManager; 51k}LH
d0aXA+S%
/** Qte5E}V`
* @author Joa Cj0r2^`
*/ ]rG=\>U3~
publicclass UserManagerImpl implements UserManager { bY~K)j
v3&
?qjdmB|w
private UserDAO userDAO; /@9Q:'P
pv]@}+<Dt
/** g NI1W@)
* @param userDAO The userDAO to set.
t ed:]
*/ ytcLx77`:
publicvoid setUserDAO(UserDAO userDAO){ <XeDJ8
'
this.userDAO = userDAO; s%jBIeh
} J
n.7W5v
iXWHI3
/* (non-Javadoc) uKJ:)oyaCP
* @see com.adt.service.UserManager#listUser w S
q<09]i
(org.flyware.util.page.Page) jX7K-L
*/ mA(kq
public Result listUser(Page page)throws xQFRM aQE
YgEd%Z%4
HibernateException, ObjectNotFoundException { /~"-q
int totalRecords = userDAO.getUserCount(); v`S5[{6
if(totalRecords == 0) i/X3k&
throw new ObjectNotFoundException %KyZ15_(-L
%xgP*%Sv2
("userNotExist"); 4&*lpl*N
page = PageUtil.createPage(page, totalRecords); ~>:JwTy
List users = userDAO.getUserByPage(page); o]?
yyP
returnnew Result(page, users); v^C\
GDH
} ]j&m\'-s
ioi/`iQR
} wkt4vE87
qCI&H7u@
>k
@t.PeoV
?'V78N sA
RRO@r}A!y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 01n!T2;yW}
c^|8qvS$
询,接下来编写UserDAO的代码: Z!v,;MW
3. UserDAO 和 UserDAOImpl: @[^ 3yC#
java代码: eu(Fhs
0]>bNbLB"
~A0AB
`7
/*Created on 2005-7-15*/ =-dnniKW4
package com.adt.dao; =]@Bc
7@
Zr}>>aIJ]k
import java.util.List; amsl>wc!
11PL1zzH
import org.flyware.util.page.Page; D4$b-?y
%<yW(s9{
import net.sf.hibernate.HibernateException; r`"_D%kc
ev&l=(hY
/** ]D6<6OB
* @author Joa kHK<~srB
*/ }wf8y
publicinterface UserDAO extends BaseDAO { sX?arI=_U
~D5
-G?%$"
publicList getUserByName(String name)throws }-[l)<F:
X"Eqhl<t
HibernateException; SrA6}kS
K E\>T:
publicint getUserCount()throws HibernateException; XU'(^Y8Imz
~vF*&^4Vh
publicList getUserByPage(Page page)throws O!Ue0\1Kj0
],c0nz^%BR
HibernateException; Kj0)/Fjl+
% 3#g-
} v=^^Mr"Z^
=o@}~G&HA
rbf5~sw&8+
mpYBMSLM
!KV!Tkx h
java代码: " lD -*e4
zZ}.2He8
C5=^cH8
/*Created on 2005-7-15*/ )F9IzR-&m
package com.adt.dao.impl; Qe~C}j%
j Hq+/\
import java.util.List; I85wP}c(
0+0Y$;<
import org.flyware.util.page.Page; wW TuEM
PCCE+wC6
import net.sf.hibernate.HibernateException; X}B]5
import net.sf.hibernate.Query; &Zz&VwWR
8h
ol4'B
import com.adt.dao.UserDAO; iu{y.}?
@G&oUhS
/** `y'%dY}$n
* @author Joa 3B#fnj
*/ 9Zx| L/\
public class UserDAOImpl extends BaseDAOHibernateImpl *r>Y]VG;S
1drg5
implements UserDAO { K`=U5vG^
q4:zr
/* (non-Javadoc) "4XjABJ4'
* @see com.adt.dao.UserDAO#getUserByName !@V]H
#cR5k@
(java.lang.String) 41R~.?
*/ X>dQK4!R
publicList getUserByName(String name)throws 2Jo|P A`9
(ht"wY#T<(
HibernateException { n(A;:)W{
String querySentence = "FROM user in class +46& Zb35
i% 0qN
com.adt.po.User WHERE user.name=:name"; Ps!
\k%FUl
Query query = getSession().createQuery P w6l'
^cdbM
(querySentence); r0z8?
query.setParameter("name", name); E:}s6l
return query.list(); Njo.-k
} L `2{H%J`
_bh$
t
/* (non-Javadoc) >>=zkPy
* @see com.adt.dao.UserDAO#getUserCount() 25G~rklk
*/ VU\G49
publicint getUserCount()throws HibernateException { B4OFhtYE
int count = 0; }T%E;m-
String querySentence = "SELECT count(*) FROM 1%@i4
gC6Gm':c
user in class com.adt.po.User"; yFo8x[
Query query = getSession().createQuery a;i}<n7
tm;\m!^X{
(querySentence); TPJuS)TU9
count = ((Integer)query.iterate().next uxW |&q
7WV"Wrl]
()).intValue(); %i&am=
return count; MDpx@.A,
} ][f 0ZMa
fN`Prs A
/* (non-Javadoc) -6q7ze{@
* @see com.adt.dao.UserDAO#getUserByPage BT:b&"AR[
_J>Ik2EF
(org.flyware.util.page.Page) :>y5'q@R
*/ 98}l`J=i
publicList getUserByPage(Page page)throws ~LH).\V
@&h_+|:-
HibernateException { Q{hK+z`D
String querySentence = "FROM user in class G$`hPNSh
$9@Z\0
com.adt.po.User"; ?:PF;\U
Query query = getSession().createQuery %AMF6l[
_=w=!U&W
(querySentence); d.sn D)X
query.setFirstResult(page.getBeginIndex()) a/d8_(0
.setMaxResults(page.getEveryPage()); nQw, /Lk
return query.list(); (!ud"A|ab4
} &WbHM)_n
UuJ gB)
} q!d7Ms{q
]VVx2ERs
iA2TvP#
17rg!'+
5Shc$Awc!
至此,一个完整的分页程序完成。前台的只需要调用 yWYsN
5N>L|J2
userManager.listUser(page)即可得到一个Page对象和结果集对象 5t-(MY
c*8k _o,
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?f6Fj
P+p:Ed80
webwork,甚至可以直接在配置文件中指定。 ;S2/n$Ju_
m]++
!
下面给出一个webwork调用示例: cMUmJH
java代码: P; =,Q$e8
%yy|B
g*U[?I"sC
/*Created on 2005-6-17*/ 7*&q"
package com.adt.action.user; _t7aOH
-A8CW9|mk
import java.util.List; ~:A=o?V2
4!+IsT
import org.apache.commons.logging.Log; jW|M)[KJN
import org.apache.commons.logging.LogFactory; 9&4z4@on
import org.flyware.util.page.Page; CJLfpvV
orF8%
import com.adt.bo.Result; |>p?Cm
import com.adt.service.UserService; q-0(
Wx9|
import com.opensymphony.xwork.Action; CwzDkr&QC_
:2&W9v
/** [{-;cpM\
* @author Joa 5
.bU2C
*/ PwxRu
publicclass ListUser implementsAction{ Y&b JKX
Pu]Pp`SP
privatestaticfinal Log logger = LogFactory.getLog oGZ%w4T
OEgp!J
(ListUser.class); >]8H@. \
ON3~!Q)
private UserService userService; Rp""&0
v+`gQXJ"G
private Page page; |rk4,NG.
1O;q|p'9
privateList users; w>gB&59r
~@Eu4ip)F
/* f>_' ]eM%
* (non-Javadoc) Y]{~ogsn$:
* |"EQyV
* @see com.opensymphony.xwork.Action#execute() 4] I7t
*/ KP]{=~(
publicString execute()throwsException{ vqJjAls
Result result = userService.listUser(page); ;l=ZW
page = result.getPage(); +(|
,Ke
users = result.getContent(); lK3Z}e*eXQ
return SUCCESS; (E?X@d iu
} m&8'O\$
^NiS7 )FX
/** niJtgK:H^
* @return Returns the page. iyf vcKO
*/ 3It9|Y"6[
public Page getPage(){ 'e06QMp@
return page; C.;H?So(
} p{4nWeH?B
p!3!&{
/** 3]g|Cwu
* @return Returns the users. 0T7""^'&
*/ gCY%@?YyN
publicList getUsers(){ Mu]1e5^]
return users; CQm(N
} wLz@u$u?
&C=[D_h
/** f^?k?_~PN
* @param page [kyIF\0
* The page to set. RwptFO
*/ j LG
Q^v"
publicvoid setPage(Page page){ a$ FO5%o
this.page = page; VsM~$
)
}
V
t@]
y d4\%%]
/** m<uBRI*I
* @param users "WE*ED
* The users to set. fTg^~XmJ
*/ +GqUI~a
publicvoid setUsers(List users){ hMvLx>q3)
this.users = users; YRm6~c
} E1-BB
m3i+b
/** 7$u}uv`j
* @param userService i917d@r( <
* The userService to set. zBTyRL
l
*/ I[v6Y^{q
publicvoid setUserService(UserService userService){ %^CoWbU
this.userService = userService; -'mTSJ.}
} I8:A]
} ruQ1Cph
RO+N>Wkt
HJeZm
eQqx0+-0c
w[X/|O
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, qmx4hs8sh
s/0S]P]}f
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 DYFfq
sV`!4
u7%}
么只需要: 7dbGUbT
java代码: ?(d<n
oi:!YVc
6wY6*R
<?xml version="1.0"?> Oq3]ZUVa
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork KJ;;825?
`}Z`aK
1.0//EN" "http://www.opensymphony.com/xwork/xwork- [Y_CRxa\u
hiQ #<
1.0.dtd"> mxfmK +'_
FLzC kzJ:6
<xwork> qPG>0
O
kMP3PS
<package name="user" extends="webwork- Mo~zq.
$"[5]{'J
interceptors"> _^ny(zy(
nqMXE82
<!-- The default interceptor stack name qRnD{g|{1
@nOj6b
--> E6Uiw]3
<default-interceptor-ref 7U,[Ruu
b>Em~NMu_
name="myDefaultWebStack"/> .L#U^H|
_aj,tz
<action name="listUser" K*[`s'Ip-
y8arFG
class="com.adt.action.user.ListUser"> |.EC>D/
<param n/Fx2QC{
@&xWd{8'
name="page.everyPage">10</param> Hru~Y}V
<result k ^(RSu<
ly~tB LH}
name="success">/user/user_list.jsp</result> _ ,~D]JYE
</action> !/RL.`!>
u]uZc~T
</package> &A!?:?3%O
fDD^?/^
</xwork> !<#,M9
EA&
fIwG9cR
uoi~JF
6O0CF}B*
'}BYMEd/m%
G'IRqO*]
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 wx[Y2lUh6
$WICyI{$
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。 ; &i