Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 {fY(zHC
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Ex6Kxd}8
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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 '-#gQxIpD
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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 6U,:J'5gP
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分页支持类: '1d0
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java代码: Y5*A,piq
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package com.javaeye.common.util; [=:4^S|M
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import java.util.List; W k "_lJ
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publicclass PaginationSupport { ;a[3RqmKW
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publicfinalstaticint PAGESIZE = 30; a;(,$q3M
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privateint pageSize = PAGESIZE; [P]M)vJ**
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privateList items; Y"dTm;&
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privateint totalCount; ^plP1c:
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privateint[] indexes = newint[0]; [Uj,, y.wB
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privateint startIndex = 0; #Zn+-Ih
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public PaginationSupport(List items, int Mi`t$hmP
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totalCount){ !m9g\8tE
setPageSize(PAGESIZE); avqJ[R
setTotalCount(totalCount); o/!a7>xO4
setItems(items); l_fERp#y
setStartIndex(0); fi6_yFl
} /|<0,oz oJ
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public PaginationSupport(List items, int ^AO2%09.S
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totalCount, int startIndex){ NE Z ]%
setPageSize(PAGESIZE); O^R^Aw
setTotalCount(totalCount); be.Kx< I
setItems(items); , qhv(
setStartIndex(startIndex); X<H+Z2d
} <"S/M]9
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public PaginationSupport(List items, int Ki3wqY
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totalCount, int pageSize, int startIndex){ ?QzN\fY;
setPageSize(pageSize); %'dsb7n
setTotalCount(totalCount); 5}_,rF?cX
setItems(items); 'RCX6TKBnR
setStartIndex(startIndex); _?>f9K$1
} T9gQq
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publicList getItems(){ uC1v^!D
return items; 4$v08zZ
} ;'| t>'0_
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publicvoid setItems(List items){ ' :,p6
this.items = items; N_E:?Jo
} }sGH}n<9*
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publicint getPageSize(){ }-M%$~`
return pageSize; =7U8`]WA
} (( Wq
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publicvoid setPageSize(int pageSize){ rjT!S1Hs
this.pageSize = pageSize; h&?tF~h
} 26c1Yl,DMn
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publicint getTotalCount(){ 0CUUgwA/
return totalCount; cX@72
} ~r>N
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publicvoid setTotalCount(int totalCount){ XAc#ywophi
if(totalCount > 0){ 9Vv&\m!0
this.totalCount = totalCount; las|ougLy
int count = totalCount / ;-T%sRI:|
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pageSize; 4 5\%2un
if(totalCount % pageSize > 0) 6 {tW$q
count++;
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indexes = newint[count]; lO0 PZnW9
for(int i = 0; i < count; i++){ [.`#N1-@M
indexes = pageSize * ]i@VIvYq
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} d.uJ}=|
}else{ bPtbU:G
this.totalCount = 0; bI~(<-S~K
} ro4 XA1
} )fz<n$3|$#
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publicint[] getIndexes(){ K"r'w8P
return indexes; \[w82%U
} &Q"Ox{~W
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publicvoid setIndexes(int[] indexes){ P:yMj&)
this.indexes = indexes; @cZNoD
} 0SBiMTm
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publicint getStartIndex(){ e&(Di,%:
return startIndex; skn`Q>a
} Yg6 f
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publicvoid setStartIndex(int startIndex){ yA+:\%y$
if(totalCount <= 0) j6KGri
this.startIndex = 0; 9+\3E4K
elseif(startIndex >= totalCount) W=Ru?sG=
this.startIndex = indexes RvF6bIqo
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[indexes.length - 1]; eJrJ5mlI`
elseif(startIndex < 0) L;0ZB=3n
this.startIndex = 0; Zv*Z^; X9
else{ do9@6[{Sv
this.startIndex = indexes 6XO%l0dC.
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[startIndex / pageSize]; Cu0N/hBT
} L
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} mzz77i
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publicint getNextIndex(){ ui,#AZQ#{4
int nextIndex = getStartIndex() + I"^ `!8<q
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pageSize; &LO<!WKQ
if(nextIndex >= totalCount) 1Ig@gdmz
return getStartIndex(); 37 wm[Z
else 42?X)n>
return nextIndex; ~B%=g)w
} ^<R*7mB*
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publicint getPreviousIndex(){ ,o}!pQ
int previousIndex = getStartIndex() - 3
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pageSize; HPAd@5d(
if(previousIndex < 0) %Lexu)odW
return0;
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else ?]081l7cd
return previousIndex; !Jw
} t+k"$zR
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} hSc$Sa8
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抽象业务类 ,qak_bP
java代码: l
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/** yOGaW~
* Created on 2005-7-12 *usfJ-
*/ I.j`h2
package com.javaeye.common.business; MI|DOp
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import java.io.Serializable; eP-q[U?$n
import java.util.List; Pv{ {zyc
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import org.hibernate.Criteria; LbtcZ)D!
import org.hibernate.HibernateException; LWc}j`Wd
import org.hibernate.Session; K IiV z<
import org.hibernate.criterion.DetachedCriteria; q[Hxy
import org.hibernate.criterion.Projections; ^ q @.yL
import
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org.springframework.orm.hibernate3.HibernateCallback; ;VM/Cxgep
import h{S';/=8
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org.springframework.orm.hibernate3.support.HibernateDaoS =L9sb!
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upport; *'vX:n&t
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import com.javaeye.common.util.PaginationSupport; ^<$dTr'
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public abstract class AbstractManager extends Yva^JB
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HibernateDaoSupport { 9zEO$<e o
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privateboolean cacheQueries = false; :#"gQ^YNp
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privateString queryCacheRegion; \szx.IZT
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publicvoid setCacheQueries(boolean ?C//UN;
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cacheQueries){ bS<lB!
this.cacheQueries = cacheQueries; tXcc#!'4C
} (ta!4h,
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publicvoid setQueryCacheRegion(String Axhe9!Fm
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queryCacheRegion){ [#kfl
this.queryCacheRegion = aAF:nyV~~0
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queryCacheRegion; z9U<Z^4z+
} ++F #Z(p
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publicvoid save(finalObject entity){ OljUK,I]
getHibernateTemplate().save(entity); Xz4!#,z/
} Y2!OJuyGc
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publicvoid persist(finalObject entity){ QK<sibDI
getHibernateTemplate().save(entity); LpeQx\
} BhLYLlXPY
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publicvoid update(finalObject entity){ ]8*g%
getHibernateTemplate().update(entity); 2PE|4zG
} mEv<r6qDT
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publicvoid delete(finalObject entity){ Zk"'x,]#
getHibernateTemplate().delete(entity); .slA}
} thDQ44<#)
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publicObject load(finalClass entity, %RG kXOgp
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finalSerializable id){ c^><^LGb
return getHibernateTemplate().load fAm^-uq[
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(entity, id); /jaTH_Q),:
} CO%7^}xSE,
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publicObject get(finalClass entity, 4Pe%*WTX
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finalSerializable id){ _?M34&.X
return getHibernateTemplate().get O
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(entity, id); jB!p,fqcb
} ('xIFi
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publicList findAll(finalClass entity){ ;e415T
return getHibernateTemplate().find("from z85%2Apd
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" + entity.getName()); NQz*P.q
} 4='Xhm
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publicList findByNamedQuery(finalString nICc}U?k
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namedQuery){ u,AP$+Qk
return getHibernateTemplate FkY}6
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().findByNamedQuery(namedQuery); C-E~z{
} r&oR|-2hRk
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publicList findByNamedQuery(finalString query, Q)c3=.[>
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finalObject parameter){ (hNTr(z
return getHibernateTemplate E-IV v
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().findByNamedQuery(query, parameter); qmqWMLfC
} O 7RIcU
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publicList findByNamedQuery(finalString query, .DsdQ4Y
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finalObject[] parameters){ -{`8Av5)E%
return getHibernateTemplate p[R4!if2
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().findByNamedQuery(query, parameters); bCMo8Xh
} 60,z! Vv
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publicList find(finalString query){ r5 tn'
return getHibernateTemplate().find O+x"c3@Z)D
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(query); '&hz*yk
} \4Uhc3
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publicList find(finalString query, finalObject YBh|\
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parameter){ R!i\-C1 S
return getHibernateTemplate().find 4`yE'%6.}
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(query, parameter); JfD-CoQS'
} '41'Gn
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public PaginationSupport findPageByCriteria P5Lb)9_Jw
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(final DetachedCriteria detachedCriteria){ &~mJ
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return findPageByCriteria ^h\(j*/#X
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); {p\ll
} nQGl]2
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public PaginationSupport findPageByCriteria Q,nJz*AJ
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(final DetachedCriteria detachedCriteria, finalint CvhVV"n
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startIndex){ FKZ'6KM&A
return findPageByCriteria >``sM=W at
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(detachedCriteria, PaginationSupport.PAGESIZE, "I3
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startIndex); Ez8k.]q u
} GYZP?E p*
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public PaginationSupport findPageByCriteria 0=0,ix7?#
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(final DetachedCriteria detachedCriteria, finalint H )51J:4
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pageSize, 6k_Uq.<X
finalint startIndex){ z$gtGrU
return(PaginationSupport) y'aK92pF:
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate /#WvC;B
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(Session session)throws HibernateException { {J1iheuS}
Criteria criteria = Y-UXr8
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detachedCriteria.getExecutableCriteria(session); NbC2N)L4
int totalCount = h ;@c%Vm
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((Integer) criteria.setProjection(Projections.rowCount @U3:9~Q
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()).uniqueResult()).intValue(); Ur]/kij
criteria.setProjection lA%FS]vh
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(null); T|8:_4/l
List items = lJ]]FuA-Q
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criteria.setFirstResult(startIndex).setMaxResults Bn9#F#F<
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(pageSize).list(); ]#Cc7wa
PaginationSupport ps = (dZ]j){
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new PaginationSupport(items, totalCount, pageSize, y XKddD
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startIndex); dB6['z)2
return ps; ZNne 8
} (i L*1f
}, true); :hT.L3n,
} k 3H0$1
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public List findAllByCriteria(final 8\"Gs z
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DetachedCriteria detachedCriteria){ |_+#&x
return(List) getHibernateTemplate d)S`.Q
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().execute(new HibernateCallback(){ 7nNNc[d*=
publicObject doInHibernate Y/6>OD
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(Session session)throws HibernateException { >{QO$F#
Criteria criteria = V y$*v
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detachedCriteria.getExecutableCriteria(session); d&CpaOSu
return criteria.list(); 3<Zp+rD
} i(pHJP:a:
}, true); h}!9?:E
} ~uH_y-
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public int getCountByCriteria(final L-}J=n\
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DetachedCriteria detachedCriteria){ jQzl!f1c3
Integer count = (Integer) zPND$3&'
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getHibernateTemplate().execute(new HibernateCallback(){ *<W8j[?
publicObject doInHibernate mM72>1~L*
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(Session session)throws HibernateException { ,5"(m?[m
Criteria criteria = PBnH#zm
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detachedCriteria.getExecutableCriteria(session); tnaFbmp
return 9M;t4Um
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criteria.setProjection(Projections.rowCount k`Ifl)
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()).uniqueResult(); 'Zp{
} y0sce
}, true); !}z'"l4i
return count.intValue(); <|4$TH^t
} s6@mXO:H^
} ^\AeX-q2v'
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用户在web层构造查询条件detachedCriteria,和可选的 &K\80wGK
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 LXK!4(xa W
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PaginationSupport的实例ps。 L)bMO8JH~m
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ps.getItems()得到已分页好的结果集 )Q'E^[Ua
ps.getIndexes()得到分页索引的数组 NC%hsg^0/
ps.getTotalCount()得到总结果数 Y@0'0
ps.getStartIndex()当前分页索引 ZrTB%
ps.getNextIndex()下一页索引 Ctz#9[|
ps.getPreviousIndex()上一页索引 IibrZ/n6
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 SlG v
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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 ixu*@{<Z(
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一下代码重构了。 W5
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我把原本我的做法也提供出来供大家讨论吧: Or5?Gt
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首先,为了实现分页查询,我封装了一个Page类: 2K91E}
java代码: [i`
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/*Created on 2005-4-14*/ X
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package org.flyware.util.page; -`~qmRpqY
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/** N&NBn(
* @author Joa a:)FWdp?9
* [CI&4) #
*/ _J
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publicclass Page { f8]sjeY
! I@w3`
/** imply if the page has previous page */ x%}D+2ro-t
privateboolean hasPrePage; VI2lwE3
hpAdoy[
/** imply if the page has next page */ )hZ7`"f,ZN
privateboolean hasNextPage; 1ML L
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/** the number of every page */ Y@+Rb
privateint everyPage; e xb}
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/** the total page number */ UCLM*`M
privateint totalPage; Ga7E}y%
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/** the number of current page */ $D^\[^S
privateint currentPage; |p6d]#z3
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/** the begin index of the records by the current TpKAdrY
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query */ x0
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privateint beginIndex; <~smBd
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/** The default constructor */ lMFR_g?r
public Page(){ NI V}hf YF
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} o<Zlm)"%1
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/** construct the page by everyPage _?c.m*)A
* @param everyPage nGF
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* */ X1^VdJE
public Page(int everyPage){ %B%_[<B
this.everyPage = everyPage; >fBPVu\PA
} Rt8[P6e"q
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/** The whole constructor */ C`.YOkpj
public Page(boolean hasPrePage, boolean hasNextPage, NL9.J@"b
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int everyPage, int totalPage, cgb>Naa<
int currentPage, int beginIndex){ ';I}6N
this.hasPrePage = hasPrePage; 51k}LH
this.hasNextPage = hasNextPage; *qpu!z2m||
this.everyPage = everyPage; z=D5*
this.totalPage = totalPage; fd)8lK[KJ"
this.currentPage = currentPage; (!}N&!t
this.beginIndex = beginIndex; pv]@}+<Dt
} j
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/** s%jBIeh
* @return gT)(RS`_)
* Returns the beginIndex. IK -vcG
*/ _^<vp
publicint getBeginIndex(){ @M'k/jl
return beginIndex; #
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} TNu %_
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/** \RDN_Z
* @param beginIndex Thggas,
* The beginIndex to set. }i+C)VUX
*/ ~>:JwTy
publicvoid setBeginIndex(int beginIndex){ rc=E%Qv%?
this.beginIndex = beginIndex; } 9@rhW
} Q6
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/** t#(NfzN
* @return fk}Raej g
* Returns the currentPage. !.R-|<2|6
*/ @[^ 3yC#
publicint getCurrentPage(){ WAn@8!9
return currentPage; e#}t
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} ZcA"HD%
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/** lO@-*m$
* @param currentPage "5JMk
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* The currentPage to set. e{8C0=
*/ Rxy|Ag/I;V
publicvoid setCurrentPage(int currentPage){ s.z)l$
this.currentPage = currentPage; U`*we43
} I]ej ]46K
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/** k7Nx#%xx
* @return &^ERaPynd
* Returns the everyPage. 2?,lr2
*/ J.~@j;[2
publicint getEveryPage(){ C?. ;3 h
return everyPage; yK{P%oh)
} !MSa -
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/** n l5+#e*\
* @param everyPage QmBHD;Gf
* The everyPage to set. X[J<OTj`$
*/ 2K~v`c*4
publicvoid setEveryPage(int everyPage){ >uCO=T,|
this.everyPage = everyPage; lR?1,yLp
} TrDTay
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/** ,5 8-h?B0v
* @return 3B#fnj
* Returns the hasNextPage. ,$]m1|t@z
*/ wgSFL6Ei
publicboolean getHasNextPage(){ 7gtaI3
return hasNextPage; z{.&sr>+v
} #cR5k@
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/** UXSwd#I&
* @param hasNextPage ~,W|i
* The hasNextPage to set. V xN!Ki=
*/ b?k,_;\
publicvoid setHasNextPage(boolean hasNextPage){ .t^1e
this.hasNextPage = hasNextPage; !le#7Kii
} @>`N%wH'
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/** /p-k'387
* @return %5ov!nm7
* Returns the hasPrePage. 7\dt<VV
*/ T&dc)t`o
publicboolean getHasPrePage(){ M!G/5:VZ
return hasPrePage; RCkmxO;b&
} N]BH6 7<
tm;\m!^X{
/** k]4CN
* @param hasPrePage &w_8E+YZ
* The hasPrePage to set. h\C1:0x{
*/ Kd}%%L
publicvoid setHasPrePage(boolean hasPrePage){ -6q7ze{@
this.hasPrePage = hasPrePage; * R&77 o7
} H1evW
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/** X56.Y.
* @return Returns the totalPage. &Ai+t2
* q:_-#u
*/ H2_6m5[&,
publicint getTotalPage(){ @C'qbO{
return totalPage; %)}_OXWf:
} ylmVmHmc
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/** ZB}zT9JaE
* @param totalPage Lz-(1~o
* The totalPage to set. ohPXwp?]
*/ s4 Uk5<
publicvoid setTotalPage(int totalPage){ -OQ6;A"#
this.totalPage = totalPage; $a')i<m^g
} "jq F
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} cMUmJH
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ~:A=o?V2
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个PageUtil,负责对Page对象进行构造: \T!tUd
java代码: +_fxV|}P
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/*Created on 2005-4-14*/ l;J B;0<s"
package org.flyware.util.page; NSh~O!pX
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import org.apache.commons.logging.Log; !_1RQ5]^
import org.apache.commons.logging.LogFactory; (d5kD#.N
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/** gM#]o QOGE
* @author Joa .ktyA+r8v
* lGN{1djT
*/ &q[`lIV, L
publicclass PageUtil { *+cW)klm
jTz~
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privatestaticfinal Log logger = LogFactory.getLog tsTCZ);(
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(PageUtil.class); RS[QZOoW}
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/** (ft$ R?
* Use the origin page to create a new page &Ukh
* @param page ||kUi=5
* @param totalRecords #ANbhHG
* @return nJo6;_MI!
*/ ??`zW
publicstatic Page createPage(Page page, int ZC:7N{a
kEM|;&=_
totalRecords){ NXDuO_#
return createPage(page.getEveryPage(), +/~;y{G..z
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page.getCurrentPage(), totalRecords); sM'%apM#
} N(^
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/** $4&e{fLt|v
* the basic page utils not including exception 3]g|Cwu
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handler .:=G=v=1
* @param everyPage "_T8Km008
* @param currentPage wLz@u$u?
* @param totalRecords K.K=\
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* @return page 6Z3L=j
*/ 6#/v:;bF
publicstatic Page createPage(int everyPage, int VsM~$
)
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currentPage, int totalRecords){ kls
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everyPage = getEveryPage(everyPage); tjTnFP/=
currentPage = getCurrentPage(currentPage); iSg^np
int beginIndex = getBeginIndex(everyPage, wXnluE
WvJidz?5
currentPage); %d#h<e|,.
int totalPage = getTotalPage(everyPage, E2~&GkU.UN
.8EaFEd
totalRecords); iy\ 6e k1
boolean hasNextPage = hasNextPage(currentPage, _)?59
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totalPage); ^TF71uo
boolean hasPrePage = hasPrePage(currentPage); %DR8M\d1~H
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returnnew Page(hasPrePage, hasNextPage, nkn4VA?"
everyPage, totalPage, E\Et,l#|LY
currentPage, ~ '/Yp8(
p,K]`pt=
beginIndex); yhSbX4Q
} 7)#8p@Q
L6=`x a,
privatestaticint getEveryPage(int everyPage){ 7lH3)9G;
return everyPage == 0 ? 10 : everyPage; kI|7o>}<
} $"[5]{'J
zt|DHVy
privatestaticint getCurrentPage(int currentPage){ r(VznKSx
return currentPage == 0 ? 1 : currentPage; yrVk$k#6}
} z IT)Hs5
b>Em~NMu_
privatestaticint getBeginIndex(int everyPage, int LX2Re
]&
iVe"iH
currentPage){ g<(\# F}/
return(currentPage - 1) * everyPage; $4ZjN N@
} ZGZ1Q/WH
"F+m}GJ=a
privatestaticint getTotalPage(int everyPage, int C!z7sOu
8%EauwAx
totalRecords){ *'ffMnSZ
int totalPage = 0; mx3p/p
ziTE*rNJ
if(totalRecords % everyPage == 0) 1@S(v L3a
totalPage = totalRecords / everyPage; mo()l8
else |Jpi|'
totalPage = totalRecords / everyPage + 1 ; .Gq]Mrim9G
;\48Q;
return totalPage; dlJc~|
} (29BS(|!
sRKoM
privatestaticboolean hasPrePage(int currentPage){ {
d |lN:B
return currentPage == 1 ? false : true; }u?DK,R
} % db
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privatestaticboolean hasNextPage(int currentPage, -4!S?rHwd+
O'[r,|Q{
int totalPage){ %&}gt+L(M
return currentPage == totalPage || totalPage == ]b'"l
k!)Pl,nJ
0 ? false : true; oj%(@6L
}
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`),ACkU>U
7+;CA+;
} h6~H5X
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:K
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U#>K(
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 A(6n- zL
hA:RVeS{
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 h;DLD8L
)PCh;P0C
做法如下: mZ0'-ax
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 BBDt^$
_MxKfah'
的信息,和一个结果集List: B
x-"<^<
java代码: Gc*p%2c
*iiyU}x
WWjc.A$
/*Created on 2005-6-13*/ JxmFUheLt
package com.adt.bo; B0$ge"FK9
J-5E# v
import java.util.List; KvY1bMU!
2}0S%R(
import org.flyware.util.page.Page; ~sMEfY,p
[DD#YL\P
/** u#)ARCx ,w
* @author Joa {n 4W3
*/ ^^(!>n6r^
publicclass Result { 2F#DJN#
+<rWYF(ii/
private Page page; > JP}OS
'n/L1Fn
private List content; T
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/** s6(bTO.
* The default constructor ]=vRjw
*/ ;!pSYcT,
public Result(){ RN"Ur'+
super(); cm17hPe`}n
} ,d@FO|G#pt
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/**
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* The constructor using fields f^|r*@o
* UH`cWV Lpr
* @param page 9a$ 7$4m
* @param content ,w%hD*
*/ 9}$'q$0R]
public Result(Page page, List content){
]/[$3rPwZ
this.page = page; bj,cU)t0
this.content = content; &\e8c
g
} ,b9!\OWDF
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/** 8;$zD]{D1
* @return Returns the content. ZmAo9>'Kg
*/ MuF{STE>->
publicList getContent(){ #b>D^=NV>)
return content; ,A[NcFdCB
} >~*}9y0$
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/** &Ivf!Bgm{Z
* @return Returns the page. FZ5
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*/ +wGFJLHJ
public Page getPage(){ KJi8LM
return page; ypWhH
} `%_(_%K
:X 9_~
/** {sF;R.P&r
* @param content mbXW$E-&R2
* The content to set. u9j1>QU
*/ yX%NFXD
public void setContent(List content){ >!PCEw<i
this.content = content; +2,EK
} K>_~|ZN1C8
o[aIQ|G
/** q0KGI/5s4+
* @param page %mRnJgV5k
* The page to set. 9`cj9zz7
*/ VJS1{n=;k
publicvoid setPage(Page page){ I]Ws
this.page = page; eE" *c>I
} y*T@_on5
} Dop,_94G
KqvM5$3
KJW^pAj$B
8gJg7RxL
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2. 编写业务逻辑接口,并实现它(UserManager, d RHw]!.
x,Z:12H0
UserManagerImpl) mV.26D<c
java代码: ntn ~=oL
/! M%9gu
>'v{o{k|C
/*Created on 2005-7-15*/ $fwj8S7$
package com.adt.service; @+hO,WXN
V3$zlzSm,
import net.sf.hibernate.HibernateException; &{S@v9~IT
;-VXp80J
import org.flyware.util.page.Page; o"g<Vz
v*^'|QyM7
import com.adt.bo.Result; b$Q#Fv&P
;RS^^vDm
/** @Uqcym.
* @author Joa bq z*90
*/ 1 Ay.^f
publicinterface UserManager { p{;FO?
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D
public Result listUser(Page page)throws Thuwme
*/j[n$K>~`
HibernateException; gFnJDR
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} sM@1Qyv&0
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)|
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vq1u!SY
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java代码: 7*@BCu6
G3gEL)b*
i*e'eZ;)
/*Created on 2005-7-15*/ _@O.EksY3r
package com.adt.service.impl; .s>.O6(^%
?{r -z3@ N
import java.util.List; 4]no#lVRJ
+krDmU9(
import net.sf.hibernate.HibernateException; JxQGL{)
>
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import org.flyware.util.page.Page; T_oL/x_;
import org.flyware.util.page.PageUtil; ?:#$btmn?
vpoJ{TPO
import com.adt.bo.Result; <,Fj}T-
import com.adt.dao.UserDAO; R
RnT.MU
import com.adt.exception.ObjectNotFoundException; \8]("l}ms8
import com.adt.service.UserManager; j~O"=?7!O
`FAZAC\
/** -Hg,:re2
* @author Joa 8xYeaK
*/ }M &hcw<
publicclass UserManagerImpl implements UserManager { Te H_DVxj
OGPrjL+
private UserDAO userDAO; Ns.{$'ll
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/** vn ^*
* @param userDAO The userDAO to set. Fr1OzS^&(
*/ ]_2<uK}fg
publicvoid setUserDAO(UserDAO userDAO){ NQ,2pM<*-
this.userDAO = userDAO; /}=cv>S5V
} G9h B p
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/* (non-Javadoc) @"0n8y
* @see com.adt.service.UserManager#listUser fi'\{!!3m^
LR
y&/d
(org.flyware.util.page.Page) .gA4gI1kH
*/ j\2q2_f
public Result listUser(Page page)throws ig4mj47wJ
iH)-8Q
HibernateException, ObjectNotFoundException { p~dj-w
int totalRecords = userDAO.getUserCount(); d*Kg_He-
if(totalRecords == 0) >C/O >g
throw new ObjectNotFoundException rG{,8*
^'$P[
("userNotExist"); :6W* ;<o
page = PageUtil.createPage(page, totalRecords); 8C<%Y7)/
List users = userDAO.getUserByPage(page); -\M;bQV[C
returnnew Result(page, users); G/&Wc2k
} t#=FFQOt
|. LE`
} D*!9K8<o
"K#zY~>L
k4YW;6<C+
AP(%m';
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 2E0$R%\
;%PI
询,接下来编写UserDAO的代码: I5w>*F
3. UserDAO 和 UserDAOImpl: Og(|bs!6
java代码: io*iA<@Gx
$ cYKVhf
nmUMg
/*Created on 2005-7-15*/ {S5j;
package com.adt.dao; $@<cZ4
i>z {QE
import java.util.List; U
)J/so)
4_h?E:sBb
import org.flyware.util.page.Page; zl@hg<n
<CGJ:% AY
import net.sf.hibernate.HibernateException; *."50o=T
7/6%92T/B
/** X&cm)o%5Fe
* @author Joa swG!O}29OX
*/ >d$Sh`a6
publicinterface UserDAO extends BaseDAO { |Q*{yvfEo
L'<.#(|
publicList getUserByName(String name)throws +cC$4t0$^A
\Culf'iX
HibernateException; lAo S 9w
&v<Am%!N
publicint getUserCount()throws HibernateException; utBKl'`
o/mGd~
publicList getUserByPage(Page page)throws %q_b\K
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HibernateException; n@y*~sG]
kr>F=|R]
} oE'Flc.
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v_NL2eQ~
ZoroK.N4A%
_?a.S8LxJZ
java代码: c^`(5}39v
C}(9SASs%
X"O^4MnvI
/*Created on 2005-7-15*/ 0p1~!X=I
package com.adt.dao.impl; [.c'22R6
><"0GPxrx
import java.util.List; ::8c pUc`f
>PONu]^
import org.flyware.util.page.Page; @]X5g8h
}+i~JK
import net.sf.hibernate.HibernateException; ]6z ;
M;F`
import net.sf.hibernate.Query; Vl%jpjqP
p
_q]Rt
import com.adt.dao.UserDAO; AIw< 5lW
qfsu# R
/** ^ 9 FRI9?
* @author Joa nbdjk1E`~
*/ L5A?9zum/!
public class UserDAOImpl extends BaseDAOHibernateImpl *{s
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rxQ&N[r2
implements UserDAO { -1c{Jo
|7%#z~rT
/* (non-Javadoc) EN{o3@ O'
* @see com.adt.dao.UserDAO#getUserByName ;eT+Ly|{
Bd>a"3fA
(java.lang.String) 1 JB~G7
*/ qotWWe#
publicList getUserByName(String name)throws (V9 ;
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HibernateException { t$-!1jq
String querySentence = "FROM user in class vmIt!x
#0'%51Jcl
com.adt.po.User WHERE user.name=:name"; H?tX^HO:q
Query query = getSession().createQuery [LDY;k~5+
'O[0oi&
(querySentence); pT'jX^BU
query.setParameter("name", name); 6"<q{K
return query.list(); ^F:Bj&0v[
} -&JQdrs
.vWwYG
/* (non-Javadoc) 2C"[0*.[N
* @see com.adt.dao.UserDAO#getUserCount() `e^sQ>rDI
*/ sglH=0MP
publicint getUserCount()throws HibernateException { 67T=ku
int count = 0; MeW?z|x`'
String querySentence = "SELECT count(*) FROM Q Zv}\C-c
!"<~n-$B
user in class com.adt.po.User"; SmVL?wf
Query query = getSession().createQuery d34BJ<
e]-%P(}Z
(querySentence); V?&P).5)
count = ((Integer)query.iterate().next M*2
Nq=3
ndS8p]P&o(
()).intValue(); %3@-.=
return count; M3Oqto<8"
} Hp5.jor(k
'T(@5%Db
/* (non-Javadoc) 3{9d5p|\i
* @see com.adt.dao.UserDAO#getUserByPage >p
9~'
4}F~h
(org.flyware.util.page.Page) ~Aw.=Yi=
*/ t[o_!fmxZ
publicList getUserByPage(Page page)throws JasA
w7
D`3`5.b
HibernateException { -rlCE-S
String querySentence = "FROM user in class RAj>{/E#W
h&2l0|8k
com.adt.po.User"; Cf>(,rt};
Query query = getSession().createQuery ZaF9Q%
}56WAP}Z 4
(querySentence); P7\?WN$p
query.setFirstResult(page.getBeginIndex()) xQkvK=~$
.setMaxResults(page.getEveryPage()); IR|#]en
return query.list(); ;@xlrj+
} 4d\V=_);r
.I.B,wH8
} nM|F
MK^
`#"xgOSP>
?OS0.
^.PCQ~Ql
G_<4% HM
至此,一个完整的分页程序完成。前台的只需要调用 ^09-SUl^
<.&84c]/&
userManager.listUser(page)即可得到一个Page对象和结果集对象 +`tk LvM
\3`r/,wY
的综合体,而传入的参数page对象则可以由前台传入,如果用 zPN:)
wKKQAM6P1
webwork,甚至可以直接在配置文件中指定。 &%m%b5
yxAy1P;dX
下面给出一个webwork调用示例: SG]Sx4fg,Y
java代码: ?AK`M #M
Kr;;aT0P
IKV!0-={!z
/*Created on 2005-6-17*/ V!/9GeIF
package com.adt.action.user; Xw3j(`w$,
9BAvE\o0
import java.util.List; N&