Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )!VJ\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KMfIp:~
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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 rVOF
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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 m7A3i<6p
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分页支持类: elKp?YN
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java代码: c"CR_
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package com.javaeye.common.util; qD"~5vtLqQ
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import java.util.List; kAUL7_>6X
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publicclass PaginationSupport { .8'uIA{_2
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publicfinalstaticint PAGESIZE = 30; H%=;pD>o
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privateint pageSize = PAGESIZE; ^f(El(w
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privateList items; g=v'[JPd
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privateint totalCount; GM^H
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privateint[] indexes = newint[0]; v?nGAn
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privateint startIndex = 0; =b )!l9TX
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public PaginationSupport(List items, int 71<4q{n
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totalCount){ -c0*
setPageSize(PAGESIZE); xjxX4_
setTotalCount(totalCount); Om7 '_}
setItems(items); MdkL_YP}.
setStartIndex(0); \q!TI x
} 06pY10<>X
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public PaginationSupport(List items, int =(c.8d
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totalCount, int startIndex){ vgNrHq&2q
setPageSize(PAGESIZE); 0iMfyW:
setTotalCount(totalCount); C^]UK
setItems(items); PK{FQ3b2{
setStartIndex(startIndex); HDE5Mg "
} ]d|M@v~c4
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public PaginationSupport(List items, int N /2WUp
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totalCount, int pageSize, int startIndex){ -0CL#RzKR
setPageSize(pageSize); IY}GU 2#
setTotalCount(totalCount); %6V=G5+W
setItems(items); 3-0jxx(
setStartIndex(startIndex); b9b`%9/L
} $b_~
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publicList getItems(){ 7D8 pb0`;J
return items; =zp{ ^mC
} "x:-#2+h
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publicvoid setItems(List items){ eq2LV=d{m
this.items = items; -=u9>S)!c
} #H8QX5b)
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publicint getPageSize(){ JV2[jo}0N
return pageSize; PI*Z>VE?
} MpJ3*$Dr
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publicvoid setPageSize(int pageSize){ & )-fC
this.pageSize = pageSize; C}o^p"M*B3
} *li5/=UC5*
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publicint getTotalCount(){
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return totalCount; .b2%n;_>.
} 'Ze&
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publicvoid setTotalCount(int totalCount){ [H`5mY@
if(totalCount > 0){ ${t$:0R,h
this.totalCount = totalCount; fB4zqMSfE
int count = totalCount / _Mh..#)`[
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pageSize; uE#i3(
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if(totalCount % pageSize > 0) 8rz,MsFR
count++; f[OJqk
indexes = newint[count]; D/2;b;-
for(int i = 0; i < count; i++){ u<+RA
indexes = pageSize * MLDAr dvK
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i; +sd':vE
} U!lWP#m
}else{ R~dWblv
this.totalCount = 0; &b19s=Z,
} XlwyD
} 4`"Q!T_'
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publicint[] getIndexes(){ l2LO,j}
return indexes; 1Zp^X:(
} `|[UF^9
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publicvoid setIndexes(int[] indexes){ mO0#xY_z
this.indexes = indexes; $A: ?o?"7}
} Vgj[m4l
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publicint getStartIndex(){ .m%ygoO
return startIndex; c
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} 0gKSjTqo
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publicvoid setStartIndex(int startIndex){ MG,?,1_ &
if(totalCount <= 0) t$uj( y>
this.startIndex = 0; z8PV&o
elseif(startIndex >= totalCount) W%#LHluP
this.startIndex = indexes Q>/[*(.Wd
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[indexes.length - 1]; C9`x"$
elseif(startIndex < 0) 5PKdMEK|q
this.startIndex = 0; E{B40E~4
else{ {1vlz>82
this.startIndex = indexes q0_Pl*
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[startIndex / pageSize]; SYv5{bff =
} tlmfDQD
} S'q4va"
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publicint getNextIndex(){ =I)Ex)
int nextIndex = getStartIndex() + _M[T8 "e(
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pageSize; _8?r!D#P;s
if(nextIndex >= totalCount) h{VGhkU9f
return getStartIndex(); pW2-RHGJY
else @0%^\Qf2
return nextIndex;
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} 2{-'`lfM%
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publicint getPreviousIndex(){ )G$0:-J-
int previousIndex = getStartIndex() - M7AUY#)
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pageSize; R<8!lQ4s
if(previousIndex < 0) (w,
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return0; >Co5_sCe
else ;e^`r;]
return previousIndex; iD!]I$
} 2-u9%
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} )}R
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抽象业务类 ~YrO>H` B
java代码: Hz3KoO &
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/** %>k$'UWzK
* Created on 2005-7-12 5]@"f/
*/ ;PX>] r5U0
package com.javaeye.common.business; lhx]r}@'MC
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import java.io.Serializable; gLPgh%B4
import java.util.List; s4{ >7`N2
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import org.hibernate.Criteria; [5Pin>]z
import org.hibernate.HibernateException; 2t"&>1
import org.hibernate.Session; Z\*jt B:
import org.hibernate.criterion.DetachedCriteria; co%-d
import org.hibernate.criterion.Projections; $<s
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import %C(^v)"
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org.springframework.orm.hibernate3.HibernateCallback; I>z0)pB
import i6D66 E
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org.springframework.orm.hibernate3.support.HibernateDaoS "\M^jO
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upport; p v*n.U6
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import com.javaeye.common.util.PaginationSupport; InR/g@n+D1
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public abstract class AbstractManager extends JQ]A"xTIa*
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HibernateDaoSupport { 924a1
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privateboolean cacheQueries = false; yMbg1+:
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privateString queryCacheRegion; @a}jnl(2
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publicvoid setCacheQueries(boolean )wueR5P
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cacheQueries){
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this.cacheQueries = cacheQueries; eUE(vn#
} '?MT"G
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publicvoid setQueryCacheRegion(String P+t`Rw
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queryCacheRegion){ B`<K]ut
this.queryCacheRegion = (S1Co&SX
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queryCacheRegion; ct![eWsuB
} ~zT7 43
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publicvoid save(finalObject entity){ tKKQli4Mn4
getHibernateTemplate().save(entity); ,c9K]>8m`
} =S:Snk%
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publicvoid persist(finalObject entity){ zyi;vu
getHibernateTemplate().save(entity); w_]`)$9
} MGE8S$Z
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publicvoid update(finalObject entity){ wPrqFpf
getHibernateTemplate().update(entity); /[RO>Z9
} #:LI,t
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); DZE@C^0%
} _?QVc0S!
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publicObject load(finalClass entity, M=Cl|
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finalSerializable id){ ]XhX aoqL
return getHibernateTemplate().load wY6m^g$h3
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(entity, id); YecV+K'p:
} ;dVYR=l
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publicObject get(finalClass entity, GP{$w_'!J0
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finalSerializable id){ ::R5F4
return getHibernateTemplate().get \qj(`0HG
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(entity, id); |Pj]sh[^Y
} ?0J&U4
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publicList findAll(finalClass entity){ 4(D/~OG-6
return getHibernateTemplate().find("from rK} =<R
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" + entity.getName()); *~SanL\
} SA[wFc
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publicList findByNamedQuery(finalString fobnK~2
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namedQuery){ h 1REL^!c
return getHibernateTemplate OH/!Ky\@
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().findByNamedQuery(namedQuery); Zb}U 4
} r"xs?P&/$
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publicList findByNamedQuery(finalString query, S}/5W
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finalObject parameter){ !@3"vd{^
return getHibernateTemplate _`.Wib+
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().findByNamedQuery(query, parameter); 2D)B%nM[
} 'B yB1NL
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publicList findByNamedQuery(finalString query, 1=z6m7@'-
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finalObject[] parameters){ :Fh#"<A&&
return getHibernateTemplate l#bE_PD;
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().findByNamedQuery(query, parameters); +*L<"@
} k$3Iv"gbx
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publicList find(finalString query){ </]a`h]
return getHibernateTemplate().find y/>IF|aX
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(query); x@#aOf4<U
} nAaY5s0D
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publicList find(finalString query, finalObject buKSZ
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parameter){ Q4ZKgcC
return getHibernateTemplate().find 8@,8j!$8G
s((c@)M
(query, parameter); GUn$IPOM
} d}Xb8SaE%c
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public PaginationSupport findPageByCriteria -BcnJK0
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(final DetachedCriteria detachedCriteria){ OEnCN
return findPageByCriteria I/* ULR,
*BHp?cn;F2
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 08G${@D+X0
} U(/8dCyyY
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public PaginationSupport findPageByCriteria TpcJ1*t
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(final DetachedCriteria detachedCriteria, finalint 2@,rIve
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startIndex){ i5cK5MaD
return findPageByCriteria j:E3c\a
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(detachedCriteria, PaginationSupport.PAGESIZE, @Y !Jm
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startIndex); 7:e5l19 uI
} Y_nl9}&+C0
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public PaginationSupport findPageByCriteria sA2esA@C<o
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(final DetachedCriteria detachedCriteria, finalint yT|44
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pageSize, 0K4A0s_R`
finalint startIndex){ TeRH@oI
return(PaginationSupport) 4Z.Dz@.c(
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getHibernateTemplate().execute(new HibernateCallback(){ *$Y_ %}
publicObject doInHibernate xX.kKEo"d
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(Session session)throws HibernateException { .iYp9?t
Criteria criteria = W.BX6
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detachedCriteria.getExecutableCriteria(session); aC94g7)`
int totalCount = GT,1t=|&V
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((Integer) criteria.setProjection(Projections.rowCount xnxNc5$oE
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()).uniqueResult()).intValue(); EY^?@D_<
criteria.setProjection $8}'h
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(null); rvuasr~
List items = lvx[C7?
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criteria.setFirstResult(startIndex).setMaxResults u#UtPF7q
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(pageSize).list(); ?x/Lb*a^
PaginationSupport ps = Va[t'%~&zR
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new PaginationSupport(items, totalCount, pageSize, QmMA]Q
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startIndex); 5mX^{V&^
return ps; ZCuo YE$g
} m48Ab`
}, true); {YG qa$+\
} 8jY<S+[o
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public List findAllByCriteria(final oqo7Ge2
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DetachedCriteria detachedCriteria){ |w{C!Q8l
return(List) getHibernateTemplate CB#B!;I8v
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().execute(new HibernateCallback(){ <}T7;knO
publicObject doInHibernate Yv.7-DHNl
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(Session session)throws HibernateException { A7 6HM@Q
Criteria criteria = %aV~RB#
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detachedCriteria.getExecutableCriteria(session); rv`GOta*
return criteria.list(); 1@i/N
} nok-![
}, true); "'C5B>qO
} 9h/Hy aN
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public int getCountByCriteria(final v#EFklOP
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DetachedCriteria detachedCriteria){ k136n#KN1
Integer count = (Integer) $z`l{F4eMf
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getHibernateTemplate().execute(new HibernateCallback(){ 'uF75C
publicObject doInHibernate :| !5d{8S8
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(Session session)throws HibernateException { 9Y@ eXP
Criteria criteria = B#?rW*yEe
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detachedCriteria.getExecutableCriteria(session); dL_9/f4
return M2\c0^R
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criteria.setProjection(Projections.rowCount ^#IE
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()).uniqueResult(); |AT`(71
} K>C@oE[W
}, true); 0Y:)$h2?
return count.intValue(); $ w+.-Tr
} `:C2Cj
} GS7'pTsYH
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用户在web层构造查询条件detachedCriteria,和可选的 RB6Q>3g
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 pRzL}-[/v
nM ?Nf}
PaginationSupport的实例ps。 Lz!JLiMEET
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ps.getItems()得到已分页好的结果集 #d06wYz=
ps.getIndexes()得到分页索引的数组 uEf=Vj}G
ps.getTotalCount()得到总结果数 &er,Wyc(
ps.getStartIndex()当前分页索引 xkU8(=
ps.getNextIndex()下一页索引 u:Ye`]~o
ps.getPreviousIndex()上一页索引 m'N8[ o|h
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 E-($Xc
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 wph8ln"C-
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一下代码重构了。 B"zB=Aw
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我把原本我的做法也提供出来供大家讨论吧: ~y?Nn8+&f
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首先,为了实现分页查询,我封装了一个Page类: \XYidj
java代码: )2#&l
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/*Created on 2005-4-14*/ q"6$#o{~U
package org.flyware.util.page; IUDH"~f
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/** wlsx|
* @author Joa ;^u,[d
* _C(fz CK
*/ {}rnn$HQe
publicclass Page { n#}~/\P6
^#Mp@HK
/** imply if the page has previous page */ N/ '
privateboolean hasPrePage; .ZV='i()X
j S[#R_
/** imply if the page has next page */ fVf:voh
privateboolean hasNextPage; D4C:%D
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/** the number of every page */ }2;iIw`
privateint everyPage; 9_nbMs
'=%`;?j
/** the total page number */ vm{8x o
privateint totalPage; +2}cR66%
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/** the number of current page */ %P M#gnt@
privateint currentPage; 9#m3<oSJ
#/jug[wf*!
/** the begin index of the records by the current Xdo\DQn
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query */ Kh[l};/F
privateint beginIndex; F\^8k /0
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/** The default constructor */ $v[mIR
public Page(){ 3;VH'hh_
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} vd(S&&]o1
*S"RU~1_
/** construct the page by everyPage dP(.l}O
* @param everyPage /d,u"_=l
* */ ~*"ZF-c,
public Page(int everyPage){ I.G[|[. Do
this.everyPage = everyPage; HA,8O[jon
} RgUQ:
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/** The whole constructor */ }A,!|m4
public Page(boolean hasPrePage, boolean hasNextPage, KvEv0L<ky
7s3=Fa:9Q
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int everyPage, int totalPage, XzSl"U PYH
int currentPage, int beginIndex){ @eeI4Jz
this.hasPrePage = hasPrePage; U,Uy0s2r
this.hasNextPage = hasNextPage; od5nRb
this.everyPage = everyPage; m;\nMdn
this.totalPage = totalPage; \#LDX,=
this.currentPage = currentPage; rab$[?]
this.beginIndex = beginIndex; FU/:'/ L
} 4w=v
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/** ?jUgDwc(w
* @return /3Gq&[R{
* Returns the beginIndex. ZOcpF1y
*/ M2p|&Z%
publicint getBeginIndex(){ 8<mloM-4
return beginIndex; YY :{/0?
} yn$1nt4
+_$s9`@]6
/** xw_klHL-o
* @param beginIndex pe0ax-Zv
* The beginIndex to set. }/&Zo=Q$
*/ T4Vp0i
publicvoid setBeginIndex(int beginIndex){ ]'[:QGr
this.beginIndex = beginIndex; Sn4xv2/
} Knqv|jJVx1
JVkuSIR>
/** *?d\Zcj85[
* @return q~
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* Returns the currentPage. A{J?I:
*/ ^)Awjj9
publicint getCurrentPage(){ Yl>Y.SO
return currentPage; _u^3uzu
} m"/..&'GC
gaz",kK<
/** hnB`+!
* @param currentPage xvl{o
* The currentPage to set. #n{4f1TZ
*/ .\T!oSb4[
publicvoid setCurrentPage(int currentPage){ W_E^+Wl@
this.currentPage = currentPage; v]EZYEXFL)
} $Wj{B@k
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/** T9&{s-3*
* @return }T(=tfv@
* Returns the everyPage. ~!~i_L\V
*/ %(p9AE
publicint getEveryPage(){ `ovMfL.u
return everyPage; KJ32L
} l7jen=(Zb;
tc[Ld#
/** )W
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* @param everyPage } % Ie
* The everyPage to set. 89^g$ ac
*/ COu5Tu^
publicvoid setEveryPage(int everyPage){ xWXLk )A
this.everyPage = everyPage; @ Do.Wgt
} O50<h O]l
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/** X,aRL6>r
* @return 6`Y:f[VB
* Returns the hasNextPage. ``k[CgV
*/ Vm\zLWNB
publicboolean getHasNextPage(){ ukEJ D3i
return hasNextPage; ;lb
} PNo:[9`S;m
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/** $;G<!]& s
* @param hasNextPage CN ( :
* The hasNextPage to set.
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*/ qhvT,"
publicvoid setHasNextPage(boolean hasNextPage){ 3{|~'5*
this.hasNextPage = hasNextPage; 1!G}*38;
} 1}Q9y`65
; 8DtnnE
/** BRM `/s
* @return {g1"{
* Returns the hasPrePage. VFZ?<m
*/ ,M?8s2?
publicboolean getHasPrePage(){ u8KQV7E
return hasPrePage; Dt[+HCCY:
} -.?
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tY
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/** !`H{jwH
* @param hasPrePage /"st
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* The hasPrePage to set. jQm~F`z
*/ >Rt:8uurAG
publicvoid setHasPrePage(boolean hasPrePage){ ~Yg)8
this.hasPrePage = hasPrePage; +@!\3a4!
} fXWE4^jU
)'f=!'X
/** -r<8mL:yW
* @return Returns the totalPage. $Ugc:L<h+
* 6>#8^{[
*/ (nq""kO6'
publicint getTotalPage(){ .6$=]hdAp
return totalPage; Uv>e :U7 ;
} %i3[x.M
tjRwbnT"
/** X$\CC18
* @param totalPage mxF+Fp~
* The totalPage to set. PVF:p7
*/ %G2g
@2
publicvoid setTotalPage(int totalPage){ W`vPf
this.totalPage = totalPage; ysG1{NOl
} CKZEX*mPC
H
$Az,-P
} oY0b8=[
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1G12FV>M
@fmp2!?6
fi>.X99(G
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 u;H^4}
OQ
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个PageUtil,负责对Page对象进行构造: *bYU=RS
java代码: 2>^(&95M
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`lOW7Z}
/*Created on 2005-4-14*/ v\8v' EDP
package org.flyware.util.page; "@^<~bw
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import org.apache.commons.logging.Log; *q=\e 9
import org.apache.commons.logging.LogFactory; 7J5jf231
eDP&W$s#
/** 12'MzIsU's
* @author Joa ,N,@9p
* 24 [cU
*/ J`0dF<<{[y
publicclass PageUtil { ZDzG8E0Sq
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privatestaticfinal Log logger = LogFactory.getLog Hpz1Iy@
ZG1TRF "
(PageUtil.class); ^pu8\K;~
oXht$Q
/** ~Azj Y 8
* Use the origin page to create a new page 9v;[T%%
* @param page cy!P!t,@
* @param totalRecords &L?]w=*
* @return {aV,h@>
*/ >6&Rytcc]
publicstatic Page createPage(Page page, int q9{ h@y
ltkARc3
totalRecords){ :d35?[
return createPage(page.getEveryPage(), TAOsg0
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page.getCurrentPage(), totalRecords); q%q+2P>
} 0[d*Z
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/** ! jApV
* the basic page utils not including exception A#?Cts,M
0Cf'\2
handler /mp!%j~
* @param everyPage h {J io>
* @param currentPage $Lbamg->E
* @param totalRecords zmD7]?|
* @return page >#&2 5,Q
*/ N.Q}.(N0
publicstatic Page createPage(int everyPage, int seAPVzWUU
#+_=(J
currentPage, int totalRecords){ iuXXFuh
everyPage = getEveryPage(everyPage); ?RsPAL
currentPage = getCurrentPage(currentPage); ,d lq2
int beginIndex = getBeginIndex(everyPage, i9qIaG/
l44QB8
9
currentPage); 6A=k;do
int totalPage = getTotalPage(everyPage, xH`
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N$t<&5+
totalRecords); pN9U1!|uam
boolean hasNextPage = hasNextPage(currentPage, LcA7f'GVK
<6;@@
totalPage); >0iCQKq
boolean hasPrePage = hasPrePage(currentPage); #b)`as?!1
M~`^deU1
returnnew Page(hasPrePage, hasNextPage, IIGx+>
everyPage, totalPage, \Ezcr=0z{j
currentPage, 3rHn?
' e!WZvr
beginIndex); M6A0D+08
}
tmBt[
kd"nBb=
privatestaticint getEveryPage(int everyPage){ 9dAtQwGR"6
return everyPage == 0 ? 10 : everyPage; `S-%}eUv
} +!ljq~%
C GK]i.N
privatestaticint getCurrentPage(int currentPage){ { Dm@_&
return currentPage == 0 ? 1 : currentPage; b?,%M^9\`
} "WtYqXyd
^jRX6
privatestaticint getBeginIndex(int everyPage, int j$s/YI:
j$lf>.[I
currentPage){ WPpO(@sn
return(currentPage - 1) * everyPage; f<rn't{
} jy>?+hm?
stW
G`>X
privatestaticint getTotalPage(int everyPage, int s~>1TxJe
-w"lW7
totalRecords){ :r
"GZ
int totalPage = 0; ;-"q;&1e
[lSQMoi3
if(totalRecords % everyPage == 0) O
x`K7$)
totalPage = totalRecords / everyPage; Sa@'?ApH
else j+
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totalPage = totalRecords / everyPage + 1 ; `x >6Wk1
v{"yrC
return totalPage; R:Ih#2R
} F1-C8V2H
{SXSQ '=
privatestaticboolean hasPrePage(int currentPage){ ^\`a-l^
return currentPage == 1 ? false : true; ,G="wI
} [.Fq
l+
[7r^fD
A
privatestaticboolean hasNextPage(int currentPage, tq'ri-c&b
/uR/,R++
int totalPage){ k #\j \t-
return currentPage == totalPage || totalPage == [S~Bt78d%r
1/;E8{
0 ? false : true; ;34p
[RT
} yVXVH CB
:qB|~"9O
R6;#+ 1D
} Z.Dg=>G]
#XqCz>Z
UA~ 4O Q]
W,80deT
eYlI };
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 +zLw%WD[l
lEHXh2
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ;&}z
L.!jo
KDP4 7A
做法如下: :HY =^$\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xw_)~Y%\
FAM:; F30
的信息,和一个结果集List:
#QcRN?s
java代码: GRofOJ
MXEI/mDYK
Oi^cs=}
/*Created on 2005-6-13*/ ibwV#6
package com.adt.bo; 1HAnOy0
=v<A&4
import java.util.List; 0QfDg DX
-Hw3rv3o
import org.flyware.util.page.Page; gdqBT]j
vV9vB3K5?
/** EH M 59s|B
* @author Joa }#4Ek8nFR
*/ cjg~?R
publicclass Result { <~w 3[i=
6P>}7R}
private Page page; =0PGE#d{t
w >2G@
private List content; srO>l ;Vf/
NR8`nc1~
/** P3=#<Q.
* The default constructor lP]Y^Gz
*/ G'w!Aw s
public Result(){ ?)k]Vg.
super(); 3)?WSOsL:
} Z^4+ 88
vp!F6ZwO
/** +'olC^?5 }
* The constructor using fields )YAU|sCAi$
* h2Th)&Fb>
* @param page &^HVuYa.0
* @param content O
j:I @c
*/ X9FO"(J
public Result(Page page, List content){ nIfAG^?|*
this.page = page; F|5Au>t
this.content = content; oCI\yp@a
} ,5}w]6bCr
|Z2"pV
/** TKsP#Dt/
* @return Returns the content. 1>L'F8"
*/ #Y'b?&b
publicList getContent(){ h qjjd-S0
return content; Y[}A4`
} * O?Yp%5NH
Q#qfuwz
/** Ab j7
* @return Returns the page. tQNrDp+
*/ 9=T;Dxn
public Page getPage(){ m9:ah<
return page; NqOX);'L0
} ?vAhDD5
eQ8t.~5;-
/** dlCYdwP
* @param content i}v.x
* The content to set. oS9Od8
*/ ZxT
E(BQv
public void setContent(List content){ BQg3+w:>
this.content = content; &V(6N%A^U
} vS0 ii
!-3;Qj}V
/** x`@`y7(
* @param page $)o0{HsL+
* The page to set. Mz2TwU_
*/ JJbd h \
publicvoid setPage(Page page){ >8OY6wb
this.page = page; 5.&)hmpg
} vGh>1U:
} 2/s42
FoG
Jkbeh.
(g X8iKl
WR"1d\m:
:0 n+RL*5
2. 编写业务逻辑接口,并实现它(UserManager, |D/a}Av>B
GxG~J4
UserManagerImpl) Tjrb.+cua
java代码: G&1bhi52
"uIaKb
'&Y_,-i
/*Created on 2005-7-15*/ Fc \]*
package com.adt.service; FE,mUpHIR
0\ (:y^X
import net.sf.hibernate.HibernateException; E JuTv%Y8
<y^_&9
import org.flyware.util.page.Page; @/^mFqr2
Mkk.8AjC|
import com.adt.bo.Result; _[Imwu}
rg >2tgA
/** &b5(Su
* @author Joa 0^o/cSF
*/ jED.0,+K!
publicinterface UserManager { ;e5PoLc
T~Bj],k_
public Result listUser(Page page)throws u4SL:IH{D
EUcD[Rv
HibernateException; BPt? 3tC
1Pw1TO"Z
} VlA]A,P}i
;zD4#7=
}a~hd*-#
'gs P9
SKnYeT
java代码: JRFUNy1+e1
ws!~MSIy
G(#t,}S}@
/*Created on 2005-7-15*/ C7NSmZ
package com.adt.service.impl; z_ycH%p
0: hv6Ge^
import java.util.List; YuknZ&Q
/R=MX>JA;
import net.sf.hibernate.HibernateException; r W[;3yMf
`DgK$ QM
import org.flyware.util.page.Page; ~BJE~
import org.flyware.util.page.PageUtil; Pm/i,T6&\
*{fs{gFw9
import com.adt.bo.Result; b6f OHy
import com.adt.dao.UserDAO; I]e+5 E0
import com.adt.exception.ObjectNotFoundException; ;]=w6'dP!
import com.adt.service.UserManager; [F+W]Jk,
j`RG Moq
/** Z8xB
a0
* @author Joa .06D_L"M
*/ mWaij]1>
publicclass UserManagerImpl implements UserManager { Yr-SlO>
G|1.qHP[F
private UserDAO userDAO; XxmWj-=qO
6 V0Ayxg7
/** JJ?rVq1g
* @param userDAO The userDAO to set. j;coP ehB
*/ b}0h()v
publicvoid setUserDAO(UserDAO userDAO){ (
uD^_N]3
this.userDAO = userDAO; f2IH2^)P
} #vV]nI<MF.
_(h=@cv
/* (non-Javadoc) ~>=.^
* @see com.adt.service.UserManager#listUser 5qQMGN$K
*
CR#D}F
(org.flyware.util.page.Page) N?vb^?
*/ 5<ruN11G
public Result listUser(Page page)throws k B]`py!
Y#68_%[
HibernateException, ObjectNotFoundException { ?cRF;!o"
int totalRecords = userDAO.getUserCount(); /ie&uWy
if(totalRecords == 0) ~ `qWEu
throw new ObjectNotFoundException \/3(>g?4
0 x-g0]
("userNotExist"); TxG@#" ^g}
page = PageUtil.createPage(page, totalRecords); fS4W*P[B3
List users = userDAO.getUserByPage(page); sS}:O d
returnnew Result(page, users); Io3-\Ff
} $Xlr@)%
*%KIq/V
} a#r{FoU{M8
d%'#-w'
B0Wf$
s^7t
v~L\[&|_
zG ='U
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 lF}@@e)N
@L!^2v
询,接下来编写UserDAO的代码: `~u=[}w
3. UserDAO 和 UserDAOImpl: ;(`bP
java代码: xE<H@@w
~-7/9$ay5
Ex
p?x
/*Created on 2005-7-15*/ hp'oiR;~w
package com.adt.dao; =exCpW>
e*}zl>f
import java.util.List; uKk#V6t#
'D5J5+.z
import org.flyware.util.page.Page; :zKW[sF
a4^hC[a
import net.sf.hibernate.HibernateException; [6mK<A,/
rueaP
/** z U[pn)pe
* @author Joa J2VPOn
*/ ;`7~Q
publicinterface UserDAO extends BaseDAO { h76j|1gI
9t\14tVwx
publicList getUserByName(String name)throws }?Y -I>
w
~&)\8@2
HibernateException; Opu*i
M,H8ZO:R
publicint getUserCount()throws HibernateException; _r3Y$^!U
2v ~8fr4
publicList getUserByPage(Page page)throws !FP ]
u?72]?SM
HibernateException; K _VIk'RB
^R@)CIQ
} 5 [~HL_u;,
pE<a:2J
.2@T|WD!Ah
49*f=gpGj2
JE9v+a{7
java代码: |(%<FY$
t^":.}[Q
D|ze0A@
/*Created on 2005-7-15*/ i;%G Z8
package com.adt.dao.impl; !I?C8)
2: gh q
import java.util.List; -"nkC
mU4(MjP?
import org.flyware.util.page.Page; c.]QIIdK
0<`qz |_h
import net.sf.hibernate.HibernateException; BGibBF^
import net.sf.hibernate.Query; H I|a88
a8T9=KY^
import com.adt.dao.UserDAO; F!#)l*OX;
5CK\Z'c~!
/** A_@..hX(
* @author Joa ?Sh]kJO
*/ i_*yS+Z;
public class UserDAOImpl extends BaseDAOHibernateImpl 0 j!<eN=
rogy`mh\r2
implements UserDAO { 5"nq
h}5
vOlfyH>
/* (non-Javadoc) 4utwcXL
* @see com.adt.dao.UserDAO#getUserByName m=9b/Nr4
RM_%u=jC
(java.lang.String) 9)tb=
*/ _\+]/rY9o
publicList getUserByName(String name)throws UiV#w#&P
KU$,{Sn6@
HibernateException { 3<XuJ1V&
String querySentence = "FROM user in class "7%jv[
BT[|f[1
com.adt.po.User WHERE user.name=:name"; fu\j
Query query = getSession().createQuery m@+v6&,
=p.avAuSn
(querySentence); FA-cTF[,(
query.setParameter("name", name); K]$PRg1|3
return query.list(); ^O7sQ7V"f=
} j$Ndq(<tG
Nut&g"u2
/* (non-Javadoc) >A{Dpsi\
* @see com.adt.dao.UserDAO#getUserCount() [6l0|Y
*/ F;#$Q
publicint getUserCount()throws HibernateException { Y }VJ4!%U
int count = 0; }'wZ)N@
String querySentence = "SELECT count(*) FROM $Be hU
?=Ceo#Er
user in class com.adt.po.User"; -b!Z(}JK
Query query = getSession().createQuery }w4OCN\1
)=GPhC/sw
(querySentence); #^VZJ:2=|
count = ((Integer)query.iterate().next @*vVc`;
M2cGr
()).intValue(); Ti)Me-g
return count; 5?H8?~&dz
} z#&1>
9cB+x`+Lu
/* (non-Javadoc) P.Bwfa
* @see com.adt.dao.UserDAO#getUserByPage | I:@:
!%65YTxY-
(org.flyware.util.page.Page) LI.WcI3uS
*/ <Mvniz
publicList getUserByPage(Page page)throws k^ZP~.G
W6>t!1oO+
HibernateException { Ci-Ze j
String querySentence = "FROM user in class FLG"c690
BJ5MCb.w
com.adt.po.User"; $`GlXiV
Query query = getSession().createQuery *CXc{{
LGuZp?"
(querySentence); }h Wv
p
query.setFirstResult(page.getBeginIndex()) &