Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 u[q1]]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Dj}n!M`2I
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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 +b"RZ:tKp
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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 Q?-HU,RBO
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分页支持类: qq"&Bc>
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java代码: 9?a-1
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package com.javaeye.common.util; .VG$`g"
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import java.util.List; _PD RUJ
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publicclass PaginationSupport { M>W-lp^3
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publicfinalstaticint PAGESIZE = 30; Kk#g(YgNz
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privateint pageSize = PAGESIZE; px;5X4U
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privateList items; >=Hm2daN
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privateint totalCount; W`_pjld
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privateint[] indexes = newint[0]; NfvvwG;M
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privateint startIndex = 0; )';Rb$<Qn
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public PaginationSupport(List items, int T&Z%=L_Q
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totalCount){ b*Ny
setPageSize(PAGESIZE);
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setTotalCount(totalCount); eQ_dO]Q
setItems(items); sf )ojq6s
setStartIndex(0); eAKK uML
} m8'B7|s
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public PaginationSupport(List items, int y3l3XLI*b
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totalCount, int startIndex){ ?O(KmDH
setPageSize(PAGESIZE); 4np,"^c
setTotalCount(totalCount); #RAez:BI
setItems(items); V^fSrW]
setStartIndex(startIndex); 7KIOI,qb6
} L".Qf|b*
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public PaginationSupport(List items, int , ,1H#;j
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totalCount, int pageSize, int startIndex){ EOJ k7
setPageSize(pageSize); "{>I5<:t
setTotalCount(totalCount); %"tLs%"7=P
setItems(items); ?w'a^+H
setStartIndex(startIndex); Lt ;!q b.
} c4QegN
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publicList getItems(){ 0"q_c-_Bg
return items;
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} H.`>t
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publicvoid setItems(List items){ fFP>$
this.items = items; T \%{zz_(
} "#bL/b'{
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publicint getPageSize(){ 3 $7TeqfAC
return pageSize; &"GHD{ix
} @y:mj \J9
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publicvoid setPageSize(int pageSize){ l%"[857
this.pageSize = pageSize; k^3 ?Z2a
} Z#7T!/28
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publicint getTotalCount(){ 46(Vq|
return totalCount; o('W2Bs-o
} <hlH@[7!
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publicvoid setTotalCount(int totalCount){ Uw R,U#d
if(totalCount > 0){ ghvF%-."1
this.totalCount = totalCount; DVCO(
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int count = totalCount / L B`=+FD
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pageSize; 0CXh|AU
if(totalCount % pageSize > 0) v&g(6~b_>
count++; 2 mM0\ja
indexes = newint[count]; P(?i>F7s
for(int i = 0; i < count; i++){ q~*3Bk~
indexes = pageSize * Mf0!-bu
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} BLxtS
}else{ gQy{OU
this.totalCount = 0; 'VA\dpa{J
} ""`>v`\
} e*5TZ7.
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publicint[] getIndexes(){ zA+&V7bvy
return indexes; w)I!q&`Y
} =6j4_+5mnH
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publicvoid setIndexes(int[] indexes){ 2`4'Y.Qf
this.indexes = indexes; -:9E+b
} @ yJ/!9?^
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publicint getStartIndex(){ # Sfz^
return startIndex; BNU]NcA#*,
} @kU{
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publicvoid setStartIndex(int startIndex){ B ;Zsp
if(totalCount <= 0) 6itp
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this.startIndex = 0; J/(3:
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elseif(startIndex >= totalCount) ',-4o-
this.startIndex = indexes
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[indexes.length - 1]; pQ0yZpN%;
elseif(startIndex < 0) RB1c!h$u
this.startIndex = 0; cVv>"oF;~*
else{ PAF2=
this.startIndex = indexes 1_vaSEov
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[startIndex / pageSize]; J;+AG^U<
} f(q^R
} SF*!Z2K
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publicint getNextIndex(){ x7$U
int nextIndex = getStartIndex() + $q#|B3N%
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pageSize; M7vc/E}]n
if(nextIndex >= totalCount) :b+C<Bp64r
return getStartIndex(); }N;c
else :32
return nextIndex; M ,.++W\
} V^Wo%e7#u[
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publicint getPreviousIndex(){ \
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int previousIndex = getStartIndex() - k#k !AcC
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pageSize; Nx4_Oc^hY
if(previousIndex < 0) PN0l#[{EN
return0; N*JWd
else .Ajs0 T2
return previousIndex; ^T\JFzV
} \ ?['pB
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} kQlXcR
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抽象业务类 N>;"r]Rl"
java代码: $x;wnXXXM
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/** W&`_cGoP
* Created on 2005-7-12 k^I4z^O=-;
*/ GIQ/gM?Pv
package com.javaeye.common.business; ji{V#
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import java.io.Serializable; j6Acd~y\2
import java.util.List; Eugt~j3
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import org.hibernate.Criteria; s$xctIbm?,
import org.hibernate.HibernateException; w#_xV
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import org.hibernate.Session; N,|:=gD_
import org.hibernate.criterion.DetachedCriteria; @;x|+@r
import org.hibernate.criterion.Projections; 6
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import cT^,[3i:c
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org.springframework.orm.hibernate3.HibernateCallback; K'N`rx.7
import vvw6 GB,M
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org.springframework.orm.hibernate3.support.HibernateDaoS h
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upport; p"ht|x
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends S*rgYe!E
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HibernateDaoSupport { +g ovnx
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privateboolean cacheQueries = false; FX )g\=ov
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privateString queryCacheRegion; _7.Wz7 ]b
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publicvoid setCacheQueries(boolean oz%ZEi\bW
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cacheQueries){ N8:?Z#z
this.cacheQueries = cacheQueries; {c|nIwdB
} u9}}}UN!
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publicvoid setQueryCacheRegion(String f33'2PYl
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queryCacheRegion){ 95^w" [}4Q
this.queryCacheRegion = <9eQ
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queryCacheRegion; 2S}%r4$n}
} mIq6\c$
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publicvoid save(finalObject entity){ punc'~
getHibernateTemplate().save(entity); F7UY>z3jL
} @5Q}o3.zA-
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publicvoid persist(finalObject entity){ .z7XYmv
getHibernateTemplate().save(entity); wIuwq>
} XLp tJ4~v
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publicvoid update(finalObject entity){ *ghkw9/
getHibernateTemplate().update(entity); s@
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} j,eeQ KH
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publicvoid delete(finalObject entity){ sLzcTGa2:z
getHibernateTemplate().delete(entity); z^I"{eT8
} Qpiv,n
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publicObject load(finalClass entity, :^lyVQ%@
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finalSerializable id){ G+AD
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return getHibernateTemplate().load j2deb`GD
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(entity, id); ,7SLc+
} d|]F^DDuI
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publicObject get(finalClass entity, _WtX8
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finalSerializable id){ A{\7HV 5
return getHibernateTemplate().get |f'U_nE#R/
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(entity, id); g}|a-
} fGb(=l
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publicList findAll(finalClass entity){ z,}1K!
return getHibernateTemplate().find("from c>{X(Z=2
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" + entity.getName()); r
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} b|n%l5
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publicList findByNamedQuery(finalString 9c8zH{T_{
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namedQuery){ |M`B
return getHibernateTemplate rAIX(2@cR_
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().findByNamedQuery(namedQuery); nVw]0Yl
} REB8_ H"
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publicList findByNamedQuery(finalString query, <|k!wfHL
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finalObject parameter){ KM< +9`
return getHibernateTemplate YTQ|Hg6jO
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().findByNamedQuery(query, parameter); ?cCh?>h
} IK(G%dDw
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publicList findByNamedQuery(finalString query, &5Ea6j
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finalObject[] parameters){ 9c9-1iS
return getHibernateTemplate vLDMa>
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().findByNamedQuery(query, parameters); @5\OM#WT~&
} >k*QkIyq
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publicList find(finalString query){ M:6H%6eT
return getHibernateTemplate().find "w=p@/C
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(query); j\q1b:pE
} WW0N"m'
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publicList find(finalString query, finalObject lg&"=VXx51
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parameter){ 5*[zIKdt2
return getHibernateTemplate().find b:\I*WJ
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(query, parameter); C"k8M\RW?
} )9##mUt'}
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public PaginationSupport findPageByCriteria f|WNPFQ$x
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(final DetachedCriteria detachedCriteria){ E0\ '
return findPageByCriteria qc|;qPj
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \yNjsG@,
} x^8x z5:O
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public PaginationSupport findPageByCriteria #p&iH9c_
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(final DetachedCriteria detachedCriteria, finalint 6vro:`R ?
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startIndex){ k )Z?
return findPageByCriteria .sAcnf"
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(detachedCriteria, PaginationSupport.PAGESIZE, {3yzC
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startIndex); >wej1#\3
} k`Ab*M$@Xs
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public PaginationSupport findPageByCriteria 8^\DQ&D
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(final DetachedCriteria detachedCriteria, finalint 5aL0N
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pageSize, Of7j~kdh83
finalint startIndex){ 7n,nODbJ
return(PaginationSupport) $n(?oyf
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getHibernateTemplate().execute(new HibernateCallback(){ ]n${j/x
publicObject doInHibernate GuQ3$B3j
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(Session session)throws HibernateException { Bqv Oi~l
Criteria criteria = gmLGK1
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detachedCriteria.getExecutableCriteria(session); $.R$I&U
int totalCount = j +@1frp
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((Integer) criteria.setProjection(Projections.rowCount _:+W0YS
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()).uniqueResult()).intValue(); @{@x2'-A
criteria.setProjection Itr yiU9
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(null); .ZxSJ"Rk
List items = @za?<G>!'e
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criteria.setFirstResult(startIndex).setMaxResults ~ d/Doi
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(pageSize).list(); $Etf'.
PaginationSupport ps = RSG4A>%!mI
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new PaginationSupport(items, totalCount, pageSize, ^>.?kh9z
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startIndex); o(]kI?`
return ps; }=^YLu=
} ~/!Zh
}, true); wHWd~K_q
} W~.1f1)
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public List findAllByCriteria(final p
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DetachedCriteria detachedCriteria){ ^.mQ~F
return(List) getHibernateTemplate D4}WJMQ7s
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().execute(new HibernateCallback(){ p !AQ
publicObject doInHibernate 2!~j(_TA
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(Session session)throws HibernateException { {}D8Y_=9\
Criteria criteria = REW
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detachedCriteria.getExecutableCriteria(session); Up`$U~%-
return criteria.list(); 8n?P'iM
} 6>%)qc$i
}, true); !Lb9KDk
} Kk!D|NKLC
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public int getCountByCriteria(final m qPWCFP
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DetachedCriteria detachedCriteria){ Dgc[WsCEW
Integer count = (Integer) ym2\o_^(
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getHibernateTemplate().execute(new HibernateCallback(){ 5f=e
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publicObject doInHibernate +"?K00*(
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(Session session)throws HibernateException { YCeE?S1gk3
Criteria criteria = ZJP.-` U
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detachedCriteria.getExecutableCriteria(session); gA2Il8K
return hDl& K E
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criteria.setProjection(Projections.rowCount CmJI"
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()).uniqueResult(); e3F)FTG&
} A>%fE 6FY
}, true); H[*.Jd
return count.intValue(); .m7iXd{
} )cUc}Avg}
} bNFX+GA/
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用户在web层构造查询条件detachedCriteria,和可选的 Q6MDhv,
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 :&2RV_$>=
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PaginationSupport的实例ps。 u&STGc[
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ps.getItems()得到已分页好的结果集 6.EfM^[
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 y:iE'SRRK6
ps.getStartIndex()当前分页索引 VpWax]'
ps.getNextIndex()下一页索引 A8e b{qv
ps.getPreviousIndex()上一页索引 [9z<*@$-
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 R|$=Pfg~4
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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 m3F.-KPO
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一下代码重构了。 (4$lB{%
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我把原本我的做法也提供出来供大家讨论吧: , j'=sDl
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首先,为了实现分页查询,我封装了一个Page类: S?OK@UEJ
java代码: s]5wzbF O
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/*Created on 2005-4-14*/ x\3 ` W
package org.flyware.util.page; 89`AF1
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/** |ng[s6uf
* @author Joa }UXj|SY
* x@v,qF$K
*/ WB6g i2
publicclass Page { KT{<iz_
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/** imply if the page has previous page */ E0ud<'3<
privateboolean hasPrePage; /B|#GJ\\3
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/** imply if the page has next page */ QMy;?,
privateboolean hasNextPage; YDi_Gl$
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/** the number of every page */ U[U$1LSS
privateint everyPage; +'uF3-+WY
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/** the total page number */ Z)P x6\?+
privateint totalPage; L(`^T`
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/** the number of current page */ @o9EX }
privateint currentPage; ;l4rg!r(S
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/** the begin index of the records by the current *vJ1~SRV
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query */ _?1<
privateint beginIndex; !ye%A&
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/** The default constructor */ q{yz]H,
public Page(){ &r~~1BnpHm
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} B(Y{
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/** construct the page by everyPage XLqS{r~?
* @param everyPage `q7I;w+g
* */ DXSZ#^,S[W
public Page(int everyPage){ ;NLL?6~
this.everyPage = everyPage; 75!IzJG
} CyzvQfpZr
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/** The whole constructor */ 3 c@Cb`w@
public Page(boolean hasPrePage, boolean hasNextPage, 4mNL;O
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int everyPage, int totalPage, Vfg144FG'
int currentPage, int beginIndex){ &:akom8
this.hasPrePage = hasPrePage; 0eq>
this.hasNextPage = hasNextPage; 9S=9m[#y'
this.everyPage = everyPage; hS*3yCE"8
this.totalPage = totalPage; zoC/Hm
this.currentPage = currentPage; Y<w2_ +(
this.beginIndex = beginIndex; yHr/i) c
} /
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/** SQ>.P
* @return ~S"G~a(&j
* Returns the beginIndex. #4%,09+
*/ S$BwOx3QF
publicint getBeginIndex(){ uPR usG4!R
return beginIndex; b]4yFwb
} vB/MnEKR
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/** e{To&gy~
* @param beginIndex kn+`2-0
* The beginIndex to set. jl3RE|M\<
*/ ;OPz T9
publicvoid setBeginIndex(int beginIndex){ ws?p2$ Cla
this.beginIndex = beginIndex; }(op;7
} g3LAi#m
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/** uO,90g[C/R
* @return 3<m"z9$
* Returns the currentPage. 1k{ E7eL
*/ W $?1" F.
publicint getCurrentPage(){ eoTOccb!
return currentPage; `o/tpuI
} Kk9 JZ[nT'
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/** A3$
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* @param currentPage $w+g%y)
* The currentPage to set. CWCE}WU>4
*/ BI4p 3-
publicvoid setCurrentPage(int currentPage){ ^4B6IF*
this.currentPage = currentPage; yK"U:X
} i @+Cr7K,
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/** >9<h?F%S
* @return Ug3PZ7lK
* Returns the everyPage. -Zocu<Rs
*/ ;#`Z(A}
publicint getEveryPage(){ f7d)
return everyPage; y'2K7\>E
} >,uof ?
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/** e)!X9><J
* @param everyPage A){kitx-i)
* The everyPage to set. I0m/
*/ /A|ofAr)
publicvoid setEveryPage(int everyPage){ "^22Y}VB
this.everyPage = everyPage; si3i#l&.b_
} qi7dcn@d
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/** N<"_5
* @return c)iQ3_&=
* Returns the hasNextPage. >hB]T%'
*/ YCw^u
publicboolean getHasNextPage(){ [gIStKe
return hasNextPage; |I)xK@7
} iu*u|e
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/** +;FF0_
* @param hasNextPage "Q2[A]4E
* The hasNextPage to set.
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*/ <adu^5BI
publicvoid setHasNextPage(boolean hasNextPage){ .?!{. D
this.hasNextPage = hasNextPage; gTO%
} C(e!cOG
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/** ^row=5]E
* @return 6st(s@>
* Returns the hasPrePage. hLx*$Z>
*/ 2rPKZ|
publicboolean getHasPrePage(){ <(3Uu()
return hasPrePage; OEdp:dW|
} LEyn1d
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/** "9kEqz4a
* @param hasPrePage ]y-r
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* The hasPrePage to set. d 'x;]#S
*/ c7wza/r>
publicvoid setHasPrePage(boolean hasPrePage){ `1M_rG1/+
this.hasPrePage = hasPrePage; PM%./
} ~g1@-)zYxK
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/** |])%yRAGQ
* @return Returns the totalPage. ,1^)JshZ~
* zs[t<`2
*/ ^C<dr}8
publicint getTotalPage(){ OjrQ[`(E
return totalPage; Y<a/(`
} ^6J*yV%
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/** Y*wbFL6`
* @param totalPage i,;Q
* The totalPage to set. .}Bb
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*/ -cY/M~
publicvoid setTotalPage(int totalPage){ 0A5xG&
this.totalPage = totalPage; "=4=Q\0PT
} 'DntZK
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} "]zq<LmX
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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 ag|d_;
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个PageUtil,负责对Page对象进行构造: ks(PH6:]<
java代码: pSV
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/*Created on 2005-4-14*/ r~t&;yRv
package org.flyware.util.page; 4XX21<yn
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import org.apache.commons.logging.Log; r10)1`[
import org.apache.commons.logging.LogFactory; mN@0lfk;
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/** V :d/;~
* @author Joa hDmVv;M:
* &,NHk9.aq
*/ YdC:P#
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publicclass PageUtil { J0o U5d=3
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privatestaticfinal Log logger = LogFactory.getLog e[Q(OV5(R
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(PageUtil.class); #i)h0ML/e
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/** nM
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* Use the origin page to create a new page s2w.V
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* @param page '|WMt g
* @param totalRecords $t}L|"=8X
* @return ap;*qiNFQ
*/ xo^_;(;
publicstatic Page createPage(Page page, int (Ca\$p7/
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totalRecords){ K;[V`)d'
return createPage(page.getEveryPage(), fFSW\4JD=
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page.getCurrentPage(), totalRecords); 8)R)h/E>
} (">!vz
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/** 0{A VH/S
* the basic page utils not including exception :hxfd b-
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handler C_'Ug
* @param everyPage {&K#~[)
* @param currentPage [Hn+r &
* @param totalRecords (CuaBHR
* @return page 3y 0`G8P'h
*/ mnu7Y([2>
publicstatic Page createPage(int everyPage, int E37`g}ZS
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currentPage, int totalRecords){ nSd?P'PFg
everyPage = getEveryPage(everyPage); W&+UF'F2
currentPage = getCurrentPage(currentPage); ly,d =
int beginIndex = getBeginIndex(everyPage, F_V~UX1D
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currentPage); 3ck;~Ncj<
int totalPage = getTotalPage(everyPage, "%>/rh2Iq
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totalRecords); Q
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boolean hasNextPage = hasNextPage(currentPage, siyJjE)}w
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totalPage); C(W?)6?
boolean hasPrePage = hasPrePage(currentPage); IybMO5Mwn
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returnnew Page(hasPrePage, hasNextPage, I?F^c6M=
everyPage, totalPage, RQ/X{<lQ)
currentPage, <([o4%
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beginIndex); q;B-np?U
} '1.T-.4>&
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privatestaticint getEveryPage(int everyPage){ 6Y}#vZ
return everyPage == 0 ? 10 : everyPage; NSM-p.I9
} tLV9b %i(
yt_?4Hc"
privatestaticint getCurrentPage(int currentPage){ o{zo-:>Jp
return currentPage == 0 ? 1 : currentPage; {I(Euk>lR
} K6|*-Wo.
A"S})
privatestaticint getBeginIndex(int everyPage, int 7CwG(c/5
M[TgNWl/[
currentPage){ ;Iv)J|*
return(currentPage - 1) * everyPage; 7i6-Hq
} UyK|KL
R<k4LHDy
privatestaticint getTotalPage(int everyPage, int Oo=}j
o?hya.;h4
totalRecords){ Is?0q@
int totalPage = 0; 6ng
.
=
qIO)Z
if(totalRecords % everyPage == 0) fE_QB=9 cz
totalPage = totalRecords / everyPage; ApS/,cV
else ^5"s3Qn
totalPage = totalRecords / everyPage + 1 ; W@pVP4F0xM
2/>AmVM
return totalPage; ,v)@&1Wh:
} SjG=H%
G}f.fRY
privatestaticboolean hasPrePage(int currentPage){ H!oP!rzEo
return currentPage == 1 ? false : true; y4M<L. RO
} H>_%ZXL
Ng+k{vAj
privatestaticboolean hasNextPage(int currentPage, bU_9GGG|
HjV83S;
int totalPage){ :K2N7?shA
return currentPage == totalPage || totalPage == Q1s`d?P/`
U Y)YhXW
0 ? false : true; JH<q7Y6!y
} Ybd){Je"z
*"1]NAz+
c%i/ '<Afr
} 2r[Q$GPM<
52-^HV
bl}$x/
~?[@KK
F(@|p]3*
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 p,ZubRJ"
l+YpRx/T\
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 7nIg3s%
w 7=Y_
做法如下: 37M7bB0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 QGLfZvTT
QD /| zi
的信息,和一个结果集List: Y@#~8\_
java代码: eMWY[f3
mn
8A%6W
T6AFwo,Q
/*Created on 2005-6-13*/ 3(vI{[yhT
package com.adt.bo; 4*m\Zoq>
E})PNf;
import java.util.List; C{Aeud #5
8]2S'mxE
import org.flyware.util.page.Page; i,* DWD+
1VJE+3
/** 183'1Z$KA
* @author Joa }t"!I\C
*/ "FG6R'
publicclass Result { VWbgusxJ
)`;?%N\
private Page page; 80:na7$)#
nQ/(*d
private List content; 8!:4m"Y
nLo:\I(
/** 1v,4[;{
* The default constructor N"HN]Y@w
*/ ~_^nWT*BV
public Result(){ b/
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super(); ]iPTB
} R,6?1Z:J
EeL~`$f
/** k]I<%
* The constructor using fields C7)].vUN
* E/5w
H/
* @param page Kd^
._
* @param content 9J l9\y9
*/ G0a UZCw
public Result(Page page, List content){ @bD,^3 U
this.page = page; ^"*r'
this.content = content; {Ivu"<`L3
} ~EX/IIa{
B4U+q|OD#
/** !aIIjWz]
* @return Returns the content. 2BRY2EF
*/ ! =|{
publicList getContent(){ Udd|. J Rd
return content; X*d,z~k%*d
} @0Tm>s
xr.fZMOh4
/** }bjTb!
* @return Returns the page. .5_w^4`b
*/ 7\5 [lM
public Page getPage(){ m#'u;GP]k
return page; ii{5z;I]X
} ,X9Y/S
l
tPFV6n
i
/** L(AY)gB
* @param content gIRFqEz@o
* The content to set. TLO-$>h
*/ |A0kbC.
public void setContent(List content){ 3osAWSCEL
this.content = content; okr'=iDg
} /Xn I>
~TurYvf
/** &hqGGfVsd
* @param page L3i\06M
* The page to set. U
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*/ 5RZAs63t
publicvoid setPage(Page page){ qmJFXnf
this.page = page; %o*afd
} >W 8!YOc
} 4sROMk=l
[+ 1([#
)mp0k%
uXtfP?3Vy
=C5[75z#+
2. 编写业务逻辑接口,并实现它(UserManager, [(UQQa=+
uw;s](~E
UserManagerImpl) 8 rnr>Ee@
java代码: "f5u2=7 }
VZw( "a*TB
3$WK%"%T
/*Created on 2005-7-15*/ N=:yl/M
package com.adt.service; ,!u^E|24
#YhKAG@|
import net.sf.hibernate.HibernateException; saYn\o"m
:t9(T?2
import org.flyware.util.page.Page; H6e^"E
Q/0;r{@Tq}
import com.adt.bo.Result; )3z.{.F
31J7# S2
/** IKAF%0[R|j
* @author Joa )lH?XpfTjm
*/ 5.5dB2w
publicinterface UserManager { w;{k\=W3Ff
zg|yW6l)9
public Result listUser(Page page)throws 9;JUc0%
qlDLZ.
HibernateException; pOw4H67
}]tSWVb*
} {s_0[>
=XudL^GF
Awe\KJ^`
WET $H,
?Cmb3pX^\
java代码: !)_5 z<
l,sYYU+iY
$F\&?B1.
/*Created on 2005-7-15*/ QAcvv 0Hv
package com.adt.service.impl; #`}g?6VHo
P,tN;c
import java.util.List; | ql!@M(p
vT3LhN+1
import net.sf.hibernate.HibernateException; I8`.eqV
Dt.OZ4w5
import org.flyware.util.page.Page; 4Mg09
import org.flyware.util.page.PageUtil; I>G)wRpfR'
b\H(Lq17
import com.adt.bo.Result; [NaU\;w\
import com.adt.dao.UserDAO; Gf]oRNP,N
import com.adt.exception.ObjectNotFoundException; <1_?.gSi
import com.adt.service.UserManager; ]:]2f9y
7Zr jU{
/** HHtp.;L/
* @author Joa JEFW}M)UGv
*/ ed*=p
l3.
publicclass UserManagerImpl implements UserManager { =ngu*#?c4
^<sX^V+{
private UserDAO userDAO; 2ZLK`^S
x7{,4js
/** N9{ivq|fO
* @param userDAO The userDAO to set. $+*ZsIo
*/ $#"}g#u
publicvoid setUserDAO(UserDAO userDAO){ zz02F+H$Y
this.userDAO = userDAO; Zad+)~@!tq
} | %6B#uy
w&C SE
/* (non-Javadoc) =fG(K!AQ
* @see com.adt.service.UserManager#listUser :UFf6T?
;|9VPv/
(org.flyware.util.page.Page) o)1wF
X
*/ lywcT! <
public Result listUser(Page page)throws 1\zI#"b ^
Zj`eR\7~
HibernateException, ObjectNotFoundException { 1mA)=hu
int totalRecords = userDAO.getUserCount(); Ig$5Ui
if(totalRecords == 0) n>Zkx+jLj<
throw new ObjectNotFoundException =U|J{^ >I
EKwS~G.b!
("userNotExist"); l 4~'CLi
page = PageUtil.createPage(page, totalRecords); MY1
tYO
List users = userDAO.getUserByPage(page); u'?t'I
returnnew Result(page, users);
@A$%baH0
} Q"Q|]f*
q@Q|oB0W$)
} unjo&
;x+4jpH]B
x2|DI)J1'
r@s, cCK9?
]l+2Ca:-[j
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ub.pJJlC
:!{aey
询,接下来编写UserDAO的代码: uiHlaMf
3. UserDAO 和 UserDAOImpl: `EWeJ(4Z@
java代码: )Tb{O
4p %`Lv
:(I)+;M}P
/*Created on 2005-7-15*/ @JN%P}4)
package com.adt.dao; )t)tk=R9N
4Ag+
import java.util.List; U.>n]/&
,9W 0fm\t
import org.flyware.util.page.Page; vi lNl|
3PBg3Y$
import net.sf.hibernate.HibernateException; !gJAK<]iW
R<JI
/** Hi.JL
* @author Joa = ng\
*/ 5<d
Y,FvX
publicinterface UserDAO extends BaseDAO { P=u )Q _
nc$?tC9V
publicList getUserByName(String name)throws |L]dJ<
lzuPE,h
HibernateException; x-%nnC6e
h"ZF,g;a
publicint getUserCount()throws HibernateException; |vEfE{
paMw88*u
publicList getUserByPage(Page page)throws *%8,G'"r?
'7_'s1
HibernateException; _^&oNm1
NK"y@)%0
} D8Ni=.ALL
I`5MAvP
5Vut4px
i<%(Z[9Lk
. dM 0
java代码: /a9+R)Al
TR
]lP<m
{9C(\i +
/*Created on 2005-7-15*/ v
SWqOv$
package com.adt.dao.impl; {/B) YR
s'LG3YV-<
import java.util.List; hoU&'P8
Rzb663d
import org.flyware.util.page.Page; lG jdDqi
$,6= .YuY
import net.sf.hibernate.HibernateException; ](8XC_-U'
import net.sf.hibernate.Query; Uv%"45&7
p8F|]6Z
import com.adt.dao.UserDAO; NPf,9c;
}m0Lr:vq<r
/** M5P63=1+
* @author Joa FIG5]u
*/ Q[~O`Lz
public class UserDAOImpl extends BaseDAOHibernateImpl p&ow\AO
uP+
j_is
implements UserDAO { `o:)PTQNg
$ g1p!
/* (non-Javadoc) JTz1M~
* @see com.adt.dao.UserDAO#getUserByName 1
C[#]krh
BDB-OJ
(java.lang.String) fnB-?8K<
*/ Uhg[#TUK
publicList getUserByName(String name)throws 9)f1CC]
?w<x_Lo
HibernateException { S!.xmc\
String querySentence = "FROM user in class m=y6E,
_
;>Z#1~8
com.adt.po.User WHERE user.name=:name"; >n` OLHg;
Query query = getSession().createQuery [a+?z6qI\}
j-A
S {w
(querySentence); YK}(VF?&
query.setParameter("name", name); ;gW~+hW ^
return query.list(); {P = {)
} ybYSz@7
MTLcLmdO
/* (non-Javadoc) .h7b 4J
* @see com.adt.dao.UserDAO#getUserCount() sav2 .w
*/ YjdH7.js
publicint getUserCount()throws HibernateException { poXkH@[O
int count = 0; -$T5@
String querySentence = "SELECT count(*) FROM :mg#&MZj<
Dvx"4EA{7{
user in class com.adt.po.User"; _@"Y3Lqi
Query query = getSession().createQuery x/9`2X`~
- MBK/
(querySentence); kdWi!Hp
count = ((Integer)query.iterate().next 4|Y0$(6o
?V7[,I1?
()).intValue(); dC.uK^FuJ
return count; 9&2kuLp?P
} c6?5?_ne
tX)]ZuEi$
/* (non-Javadoc) \Dt0
}
?;k
* @see com.adt.dao.UserDAO#getUserByPage % yJs"%
,eZ'pxt
(org.flyware.util.page.Page) 6qHo$#iT
*/ h\.UUC&<
publicList getUserByPage(Page page)throws wx57dm+
MhJ`>.z1
HibernateException { XP(q=Mw
String querySentence = "FROM user in class kSI,Q!e\
jl7e6#zu
com.adt.po.User"; M5%xp.B
Query query = getSession().createQuery (tVY
/(~#
IE,g
(querySentence); [n< U>up
query.setFirstResult(page.getBeginIndex()) TmQ2;3%
.setMaxResults(page.getEveryPage()); VvoJ85
return query.list(); uIWCVR8`Y
} 1)
@Wcc.
*nH ?o* #
} :$94y{
^ro?.,c T
S++}kR);
ZZeqOu7^
u\Xi]pZ@X]
至此,一个完整的分页程序完成。前台的只需要调用 "M? (Ax
NtA}I)'SWU
userManager.listUser(page)即可得到一个Page对象和结果集对象 <'gCI Ia2
sL!6-[N
的综合体,而传入的参数page对象则可以由前台传入,如果用 rc;| ,\
@l@lE0
webwork,甚至可以直接在配置文件中指定。 !(o)*S
>\>HRyt%
下面给出一个webwork调用示例: yV`!Fq 1k
java代码: DU[UGJg
D|+H!f{k
pf2$%lE
/*Created on 2005-6-17*/ 8, WQ}cC
package com.adt.action.user; }Y-f+qX*
wuh$=fya
import java.util.List; Fa>Y]Y0r
@c{Z?>dUc#
import org.apache.commons.logging.Log; 31bKgU{
import org.apache.commons.logging.LogFactory; "@Te!.~A.
import org.flyware.util.page.Page; k_y@vW3
{&2$1p/9'
import com.adt.bo.Result; ETtK%%F0
import com.adt.service.UserService; ls/:/x(5d
import com.opensymphony.xwork.Action; TuX#;!p6
lSbAZ6
/** $?'z%a{
* @author Joa ^ S%4R'
*/ p?dMa_g
publicclass ListUser implementsAction{ 9@:&