Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 q{_ f"
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +'Y?K]zbt
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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 5rf Dm
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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 -L4G)%L\
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分页支持类: `K:n=hpF
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java代码: tSux5yV
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package com.javaeye.common.util; 'sXrtl7{^
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import java.util.List; *];QPi~
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publicclass PaginationSupport { pg!MtuC}
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publicfinalstaticint PAGESIZE = 30; AE+BrN
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privateint pageSize = PAGESIZE; XI|k,Ko<
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privateList items; c ~~4eia)
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privateint totalCount; Wz#Cyjo
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privateint[] indexes = newint[0]; !h4A7KBYG
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privateint startIndex = 0; 9l"=]7~%
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public PaginationSupport(List items, int (sQXfeMz
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totalCount){ tc[z/
setPageSize(PAGESIZE); c_S~{a44Ud
setTotalCount(totalCount); kS&>g
setItems(items); U]gUGD!5x
setStartIndex(0); $OdBuJA
} GS=E6
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public PaginationSupport(List items, int S<NK!89
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totalCount, int startIndex){ P`{$7ST'Hh
setPageSize(PAGESIZE); lct
setTotalCount(totalCount); lq "X_M$
setItems(items); UO&$1rV
setStartIndex(startIndex); * 30K}&T
} RqGX(Iuv
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public PaginationSupport(List items, int gN/>y1{a
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totalCount, int pageSize, int startIndex){ 8ta@@h
setPageSize(pageSize); /q\e&&e
setTotalCount(totalCount); -JF^`hBD-
setItems(items); aIFlNS,y
setStartIndex(startIndex); iLZY6?_^
} ?R#$
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publicList getItems(){ #f) TAA
return items; X.;VZwT+
} M
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publicvoid setItems(List items){ GW;%~qH[,
this.items = items; D)ri_w!Q
} ^@AyC"K
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publicint getPageSize(){ >":xnX#
return pageSize; O1\Hx8^
} 30uPDDvar
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publicvoid setPageSize(int pageSize){ LZe)_9$
this.pageSize = pageSize; sd\p[MXX
} WM
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publicint getTotalCount(){ $N)G:=M!s
return totalCount; kaekH*m~
} nPXP9wmh4x
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publicvoid setTotalCount(int totalCount){ I61S0lz/
if(totalCount > 0){ l(sVnhL6h
this.totalCount = totalCount; WsV"`ij#
int count = totalCount / "g^i%
W[O]Aal{
pageSize; Om0$6O
if(totalCount % pageSize > 0) B{j><uxl
count++; Cr7Zi>sd<!
indexes = newint[count]; 1W{N6+u
for(int i = 0; i < count; i++){ .
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indexes = pageSize * b/z-W`gw
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} @=VxWU
}else{ QE(.w
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this.totalCount = 0; #_ |B6!D!
} ^r\rpSN
} TBBnsj6e
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publicint[] getIndexes(){ 0
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return indexes; f)/Z7*Z
} |q77
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publicvoid setIndexes(int[] indexes){ [b3!H{b#
this.indexes = indexes; /88s~=
} >S +}
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publicint getStartIndex(){ -&8( MT*
return startIndex; FXof9fa_B
} 6L<:>55
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publicvoid setStartIndex(int startIndex){ Y_'ERqQ
if(totalCount <= 0) 7s|'NTp
this.startIndex = 0; C Bkoky9&
elseif(startIndex >= totalCount) X8|H5Y:
this.startIndex = indexes ]nTeTW
OM\J4"YV$
[indexes.length - 1]; 7=l~fKu
elseif(startIndex < 0) *r`=hNr
this.startIndex = 0; T+0=Ou"N
else{ 4mX(.6
this.startIndex = indexes B@,r8)D
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[startIndex / pageSize]; _\WR3Q!V
} 7OV^>"S
} Vm[Rp,"
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publicint getNextIndex(){ :;k?/KU7
int nextIndex = getStartIndex() + }%< ?]
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pageSize; !7N:cx'Qy
if(nextIndex >= totalCount) iGW|j>N
return getStartIndex(); 6j%%CWU{~
else 7H6Ts8^S
return nextIndex; \((iR>^|
} dAI^ P/y%
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publicint getPreviousIndex(){ ?JrUZXY
int previousIndex = getStartIndex() - RHF"$6EAFG
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pageSize; V%,,GmiU]
if(previousIndex < 0) W5R/Ub@g
return0; F @PPhzZ
else %_!/4^smE
return previousIndex; VI!
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} =M\yh,s!
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} T^A(v(^D
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抽象业务类 `G\
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java代码: Rk$7jZdTf
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/** Pf;OYWST
* Created on 2005-7-12 6uRE9h|
*/ e,(Vy
package com.javaeye.common.business; {v"f){
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import java.io.Serializable; WIWo4[(
import java.util.List; (Jq m9
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import org.hibernate.Criteria; 8lk/*/} =<
import org.hibernate.HibernateException; <&eJIz=
import org.hibernate.Session; @&*TGU
import org.hibernate.criterion.DetachedCriteria; frcAXh9
import org.hibernate.criterion.Projections; 0:{W
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import c)EYXo
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org.springframework.orm.hibernate3.HibernateCallback; ekx(i
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import p{E(RsA
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org.springframework.orm.hibernate3.support.HibernateDaoS o[;P@F
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upport; W6?=9].gc
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import com.javaeye.common.util.PaginationSupport; k}LIMkEa4a
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public abstract class AbstractManager extends ^!tX+`,6^
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HibernateDaoSupport { B7Ket8<J
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privateboolean cacheQueries = false; F2YBkwI
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privateString queryCacheRegion; f@sC~A. 9\
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publicvoid setCacheQueries(boolean u?>},M/
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cacheQueries){ ]MCH]/
this.cacheQueries = cacheQueries; wPI!i K@Ro
} /CALXwL
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publicvoid setQueryCacheRegion(String 9>{ml&$
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queryCacheRegion){ Gd!_9S`68
this.queryCacheRegion = G;gsDn1t
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queryCacheRegion; o2|#_tGNUy
} 3ZT3I1/D
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publicvoid save(finalObject entity){ B\D)21Ik}%
getHibernateTemplate().save(entity); o4: e1
} ttr`
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publicvoid persist(finalObject entity){ uznqq}
getHibernateTemplate().save(entity); tF[)Y#
} U:x;4
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publicvoid update(finalObject entity){ jhRr!
getHibernateTemplate().update(entity); 'Rnzu0<lF
} L=54uCv
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publicvoid delete(finalObject entity){ 3LyNi$`f
getHibernateTemplate().delete(entity); RKrNmD*rk*
} XX-(>B0L
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publicObject load(finalClass entity, ~(*tcs]hY
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finalSerializable id){ X<_HQ
return getHibernateTemplate().load dU_;2d$
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(entity, id); 0NSw^dO\
} IAbQgBvUD
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publicObject get(finalClass entity, VJ
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finalSerializable id){ @=z.^I30
return getHibernateTemplate().get Fa`%MR1
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(entity, id); vx7=I\1
} ~u!V_su]GY
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publicList findAll(finalClass entity){ vaQsG6q[
return getHibernateTemplate().find("from #c'B2Jn
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" + entity.getName()); =!DX,S7
} 0datzEns`
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publicList findByNamedQuery(finalString nT01B1/<]
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namedQuery){ $;(@0UDE
return getHibernateTemplate *MlEfmB(
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().findByNamedQuery(namedQuery); >h:'Z*9
} y5*zyd
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publicList findByNamedQuery(finalString query, 7jxx,#I:
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finalObject parameter){ 9iJ$M!
return getHibernateTemplate 4 7mT
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().findByNamedQuery(query, parameter); CvZ\Z472.j
} %2b^t*CQ
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publicList findByNamedQuery(finalString query, 6`6 / 2C$%
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finalObject[] parameters){ D/"velV
return getHibernateTemplate |ssl0/nk
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().findByNamedQuery(query, parameters); .Mb0++% W
} =Yl ea,S
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publicList find(finalString query){ JF~9efWe>
return getHibernateTemplate().find `9^+KK "
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(query); 5oCg&aT
} )qMbk7:v\
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publicList find(finalString query, finalObject (K8Ob3zN_
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parameter){ QD3tM5(Yr
return getHibernateTemplate().find a:l-cZ/!
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(query, parameter); ^dk$6%0
} zdU46|!u
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public PaginationSupport findPageByCriteria 1,)
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(final DetachedCriteria detachedCriteria){ eBxm
return findPageByCriteria OqciZ@#5n
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(detachedCriteria, PaginationSupport.PAGESIZE, 0);
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} MYjc6@=cR
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public PaginationSupport findPageByCriteria `?N0?;
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(final DetachedCriteria detachedCriteria, finalint >L!c} Ku
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startIndex){ ]7K2S{/o{
return findPageByCriteria hPNMp@Nm6
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(detachedCriteria, PaginationSupport.PAGESIZE, [H<TcT8
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startIndex); EI 35&7(
} :(X3?%
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public PaginationSupport findPageByCriteria C[
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P* `*^r3
(final DetachedCriteria detachedCriteria, finalint A|+QUPD
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pageSize, U3V5Jor#
finalint startIndex){ zX&SnT1~
return(PaginationSupport) }H\I[5*
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getHibernateTemplate().execute(new HibernateCallback(){ .nrllVG%`
publicObject doInHibernate 18Y#=uH}
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(Session session)throws HibernateException { 8;DDCop 8L
Criteria criteria = %?PFe}
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detachedCriteria.getExecutableCriteria(session); -<6?ISF2
int totalCount = n^T,R
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((Integer) criteria.setProjection(Projections.rowCount qy3@>
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()).uniqueResult()).intValue(); O[C4xq
criteria.setProjection m|qktLx
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(null); T[bC Y 6
List items = R2Fjv@Egk
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criteria.setFirstResult(startIndex).setMaxResults fu^W# "{
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(pageSize).list(); {p84fR1P
PaginationSupport ps = 9RJF
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new PaginationSupport(items, totalCount, pageSize, 4KM-$h,4O
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startIndex); 3=YpZ\l}
return ps; %tyo(HZQ
} !ajBZ>Q
}, true); $8=|<vt
} nF,F#V8l
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public List findAllByCriteria(final K($l>PB,y@
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DetachedCriteria detachedCriteria){ 6c-/D.M
return(List) getHibernateTemplate 6Wu*zY_+
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().execute(new HibernateCallback(){ =SfNA
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publicObject doInHibernate {o}U"b<+Ra
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(Session session)throws HibernateException { Dr3_MWJ+
Criteria criteria = QqA=QTZ}
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detachedCriteria.getExecutableCriteria(session); cFUD$mp
return criteria.list(); vd%g'fTy9
} LhJUoX
}, true); W[ l
} k]~o=MLmj
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public int getCountByCriteria(final s1:Wrz?4
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DetachedCriteria detachedCriteria){ $DY#04Je\=
Integer count = (Integer) ?jmP]MM
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getHibernateTemplate().execute(new HibernateCallback(){ +Nt4R:N
publicObject doInHibernate >JpBX+]5m
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(Session session)throws HibernateException { _~<sb,W
Criteria criteria = 0#*6:{/^
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detachedCriteria.getExecutableCriteria(session); xfYKUOp/
return G4*
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criteria.setProjection(Projections.rowCount m'rDoly"62
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()).uniqueResult(); #T=iS(i
} f3K-X1`]'U
}, true); mTZ/C#ir(
return count.intValue(); 1djZ5`+
} D=e*rrL7a
} z`{sD]
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用户在web层构造查询条件detachedCriteria,和可选的 >?$2`I
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 B2;P%B
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PaginationSupport的实例ps。 _*mn4n=
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ps.getItems()得到已分页好的结果集 "Z.6@
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ps.getIndexes()得到分页索引的数组 ynIe4b
ps.getTotalCount()得到总结果数 z !K2UTX
ps.getStartIndex()当前分页索引 Y{}
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ps.getNextIndex()下一页索引 @:N8V[*u
ps.getPreviousIndex()上一页索引 A8%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 6H|SiO9
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 L3eF BF/
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一下代码重构了。 ChiIQWFE
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我把原本我的做法也提供出来供大家讨论吧: 9\8ektq}Z
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首先,为了实现分页查询,我封装了一个Page类: zyPb\/
java代码: bxE~tsM"@Y
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/*Created on 2005-4-14*/ ]]|#+$ ~
package org.flyware.util.page; y[7M(K
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/** u!X~!h-6~
* @author Joa gSFZ>v*6
* !oH{=.w
*/ .$\-{)
publicclass Page { qJG;`Ugl:
`+w= p7ET
/** imply if the page has previous page */ k]ZE j/y~
privateboolean hasPrePage; EjfQF C
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/** imply if the page has next page */ @|A!?}
privateboolean hasNextPage; lJ3VMYVrUP
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/** the number of every page */ _|e&zr
privateint everyPage; )f3A\^
l~$)>?ZD
/** the total page number */ nc1~5eo
privateint totalPage; +pYgh8w@
&0kr[Ik.
/** the number of current page */ M"*NV(".g
privateint currentPage; GP+=b:C{E
P4B|l:
/** the begin index of the records by the current A{>w5T
@vq)Y2)r\
query */ Q m*z
privateint beginIndex; B-g-T>8
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/** The default constructor */ =x+1A)Q
public Page(){ -aBhN~
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} @(L}:]{@
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/** construct the page by everyPage TeuZVy8a
* @param everyPage dWzf C@]
* */ R:n|1]*f3X
public Page(int everyPage){ OybmyGHY
this.everyPage = everyPage; 2MB>NM<xO
} Q"s6HZ"YI
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/** The whole constructor */ 64b AWHv
public Page(boolean hasPrePage, boolean hasNextPage, [;hkT
sT =|"H?
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int everyPage, int totalPage, tX%
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int currentPage, int beginIndex){ _3W .:
this.hasPrePage = hasPrePage; 8p829
this.hasNextPage = hasNextPage; +s_a{iMVP
this.everyPage = everyPage; #&uajo
this.totalPage = totalPage; 8m
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this.currentPage = currentPage; BO}IN#
this.beginIndex = beginIndex; Vel(+HS
} c\[&IlM
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/** O.#Rr/+)
* @return RPMz&/k
* Returns the beginIndex. [qxpu{
*/ _[8JSw7
publicint getBeginIndex(){ ^xk4HF
return beginIndex; ^x*J4jl
} E\Wd*,/v)
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/**
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* @param beginIndex aiX4;'$x!
* The beginIndex to set.
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*/ (j:[<U
publicvoid setBeginIndex(int beginIndex){ I|bX;l
this.beginIndex = beginIndex; ve a$G~[%6
} 6qV1_M#
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/** LkafB2y
* @return _Q\rZ
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* Returns the currentPage. A$~H`W<yxB
*/ u<n['Ur}|
publicint getCurrentPage(){ \4G9fR4
return currentPage; R))4J
} bA6^RIf?
Ir` l*:j$
/** hYFi"ck
* @param currentPage a~VW?wq
* The currentPage to set. nJgN2Z
*/ Pr1OQbg]8
publicvoid setCurrentPage(int currentPage){ DjZTr}%q
this.currentPage = currentPage; KKg\n^
} b
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/** >Ir?)h
* @return +U1fa9NSn
* Returns the everyPage. /lHs]) ,
*/ Nb0T3\3W
publicint getEveryPage(){ Q&&=:97d
return everyPage; D+BflI~9mP
} ;]BNc"
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/** kmJ<AnK
* @param everyPage je:J`4k$
* The everyPage to set. DfOigLG*
*/ +miL naO~L
publicvoid setEveryPage(int everyPage){ #Guwbg
this.everyPage = everyPage; i&}LuF8
} .D=#HEshk
zs-,Y@ZL
/** C0>)WVCK
* @return fhHTp_u)2
* Returns the hasNextPage. p|r>tBv?x
*/ >LU !Z
publicboolean getHasNextPage(){ +jGUp\h%9;
return hasNextPage; |z)7XK
} ?I.bC
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/** =*WfS^O
* @param hasNextPage <U/r U9O
* The hasNextPage to set. JkNRXC:
*/ 51>OwEf<R
publicvoid setHasNextPage(boolean hasNextPage){ U,`F2yD/!
this.hasNextPage = hasNextPage; 4d-"kx3X
} {RH)&k&%
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/** `7
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* @return y(r(q
* Returns the hasPrePage. a3_pF~Qx
*/ L<N=,~
publicboolean getHasPrePage(){ XCO;t_%
return hasPrePage; 8rjiW#
} ^+dL7g?+
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/** v$|cF'yyF=
* @param hasPrePage W'C~{}c=
* The hasPrePage to set. VSm{]Z!x
*/ OmECvL'Z
publicvoid setHasPrePage(boolean hasPrePage){ )G|'PXI@,
this.hasPrePage = hasPrePage; eq36mIo
} ^pvnUODW[
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/** :W1B"T<
* @return Returns the totalPage. zAd%dbU|
* zO)3MC7l*
*/ K!SFS
publicint getTotalPage(){ >VvA&p71b
return totalPage; b,RQ" {
} s `
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/** 'di(5
* @param totalPage n ]P,5
* The totalPage to set. m2PI^?|e
*/ (%iCP/E3
publicvoid setTotalPage(int totalPage){ |Skhx9};
this.totalPage = totalPage; B["C~aF
} &qae+p?
m3 W
} 0 5o
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59M\uVWR
@ZGD'+zd?
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 UrEfFtH'
W(,3j{d2i
个PageUtil,负责对Page对象进行构造: 5}"9)LT@@w
java代码: }w/6"MJ[n
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#>dj!33
/*Created on 2005-4-14*/ !juh}q&}|
package org.flyware.util.page; 3/0E9'
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import org.apache.commons.logging.Log; xy[aZr
import org.apache.commons.logging.LogFactory; qv.s-@l8
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/** .h[yw$z6
* @author Joa NNP ut$.
* E8]kd
*/ g!DJW
publicclass PageUtil { 4Bz:n
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privatestaticfinal Log logger = LogFactory.getLog oZ,_ G,b^
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(PageUtil.class); Dg
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/** T?HW=v_a
* Use the origin page to create a new page r6gfxW5
* @param page 6,a:s:$>}R
* @param totalRecords 6tF_u D
* @return l~Rd\.O
*/ X)b@ia'"Wp
publicstatic Page createPage(Page page, int 2R];Pv
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totalRecords){ @jY=b<
return createPage(page.getEveryPage(), ;7E
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page.getCurrentPage(), totalRecords); h yK&)y?~
} (NC]S
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/** XR|U6bf]
* the basic page utils not including exception "Tz'j}< 9C
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handler YpI|=mv
* @param everyPage M>[e1y>7
* @param currentPage ]Bj2; <@y
* @param totalRecords {hFH6]TA
* @return page -}(2}~{e(
*/ 5Ky(C6E$s
publicstatic Page createPage(int everyPage, int &&g02>gE
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currentPage, int totalRecords){ ny1;]_X_
everyPage = getEveryPage(everyPage); _;M3=MTM9
currentPage = getCurrentPage(currentPage);
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int beginIndex = getBeginIndex(everyPage, )$ M2+_c
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currentPage); lg
+ >.^7k
int totalPage = getTotalPage(everyPage, YD;G+"n?T
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totalRecords); R$X~d8o>%
boolean hasNextPage = hasNextPage(currentPage, Ej8g/{
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totalPage); aW-6$=W
boolean hasPrePage = hasPrePage(currentPage); tI)|y?q
ocu,qL)W
returnnew Page(hasPrePage, hasNextPage, ,x$^^
everyPage, totalPage, XBoq/kbw!
currentPage, 2+_a<5l~
$<AaeyR!N
beginIndex); =*1NVi $n
} `Qjs{H
0` .5gxm
privatestaticint getEveryPage(int everyPage){ M*f]d`B
return everyPage == 0 ? 10 : everyPage; s VHk;:e>x
} bf|ePGW?
@S=9@3m{w;
privatestaticint getCurrentPage(int currentPage){ hJsP;y:@Lm
return currentPage == 0 ? 1 : currentPage; UWidT+'Sa
} AgZ?Ry
kg
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privatestaticint getBeginIndex(int everyPage, int K{{_qFj@<y
fjOq@thD
currentPage){ 5C&*PJ~WA
return(currentPage - 1) * everyPage; :eSsqt9]9
} nwh @F1|
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privatestaticint getTotalPage(int everyPage, int #=={h?UDT
l<BV{Gl
totalRecords){ U8AH,?]#
int totalPage = 0; 'It8h$^j
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if(totalRecords % everyPage == 0) <l$ d>,
totalPage = totalRecords / everyPage; fjVy;qJ32S
else EG;E !0
totalPage = totalRecords / everyPage + 1 ; )+hV+rM jp
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return totalPage; uO`MA%
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} c#sHnpP
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privatestaticboolean hasPrePage(int currentPage){
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return currentPage == 1 ? false : true; Vh;zV Y
} >
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privatestaticboolean hasNextPage(int currentPage, S k~"-HL|
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int totalPage){ 1J4Pnl+hN
return currentPage == totalPage || totalPage ==
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0 ? false : true; Wc[,kc
} m|;(0
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} Ve3z5d:^
by
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^ RA'E@"
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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。 pn
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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 /i'078F
sQvRupYRO
做法如下: Nr4:Gih
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 w +t@G`d
`}}:9d
的信息,和一个结果集List: ZgP%sF
java代码: vxOqo)yO
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/*Created on 2005-6-13*/ 1cLtTE
package com.adt.bo; CubQ6@,
h[ DNhR
import java.util.List; {LO Pm1K8Y
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import org.flyware.util.page.Page; bbK};u
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/** g* q#VmE
* @author Joa 2bp@m;g$
*/ lkn|>U[
publicclass Result { 8M,*w6P
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private Page page; 9%/hoA)
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private List content; m1"m KM
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/** eUyF<j
* The default constructor Kc MzY
*/ nw+~:c
public Result(){ Z'z)Oo
super(); BG>Y[u\N
} )ZG;.j
*o6}>;
/** _gvFs%J
* The constructor using fields 37#&:[w>
* LW %AZkAx
* @param page J1?;'
* @param content ~ZHjP_5Q
*/ v, $r.g;
public Result(Page page, List content){ Ot=jwvw
this.page = page; 7aG.?Ca%
this.content = content; L$ZjMJ
} 9mF'
/F*Y~>*% 1
/** /x<g$!`X
* @return Returns the content. *$tXm4
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*/ *FS8]!Qg
publicList getContent(){ j{@O%fv=
return content; ks405
} #8$?#
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/** Y-VDi.]W
* @return Returns the page. y7Po$ )8l
*/ ewDYu=`*
public Page getPage(){ mG~_*8}e<
return page; =%Y1] F
} k(gbUlCc
2M
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/** /x VHd
* @param content b?H"/Mu.
* The content to set. |23F@s1
*/ ]vrZGX
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public void setContent(List content){ CSM"Kz`
this.content = content; { 3G
} agIqca;
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/** Y:^hd809
* @param page q<3nAE$?=
* The page to set. !fh (k
*/ OO:S2-]Y>e
publicvoid setPage(Page page){ B8&q$QV
this.page = page; mdi!Q1pS
} _v!7
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} |v&)O)Jg
VB |?S|<
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,d"T2Hy
2. 编写业务逻辑接口,并实现它(UserManager, m+QS -woHn
Z@~gN5@,M
UserManagerImpl) r,5e/X
java代码: iZGbNN
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/*Created on 2005-7-15*/ G% F#I
package com.adt.service; l*CulVX
m&)/>'W
import net.sf.hibernate.HibernateException; u[a-9^&g
&RR;'wLoQT
import org.flyware.util.page.Page; >6es
5}
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import com.adt.bo.Result; "~r<ZG
1+%UZK= K
/** fB2ILRc
* @author Joa I4Do$&9<D
*/ vo/x`F'ib
publicinterface UserManager { ;qmnG3;Q
'}cSBbl&/n
public Result listUser(Page page)throws 8mX!mYO3c
2;)IBvK
HibernateException; [* xdILj
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} 2dts}G
{i>AQ+z61f
I:dUHN+@L5
^-%'ItVO
l;-2hZ
java代码: Y3@+aA
&dB@n15'A
@!;A^<{ka
/*Created on 2005-7-15*/ =svFw&q"
package com.adt.service.impl; |s/)lA:9
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import java.util.List; 8UB2 du@?
y[J9"k(@
import net.sf.hibernate.HibernateException;
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rBJ`=o z
import org.flyware.util.page.Page; G[}v?RLI
import org.flyware.util.page.PageUtil; 8P]nO+
?;#Q3Y+
import com.adt.bo.Result; <gPM/4$G
import com.adt.dao.UserDAO; C\{A|'l!x
import com.adt.exception.ObjectNotFoundException; 8{Wl
import com.adt.service.UserManager; :@(1~Hm
"]3o933D
/** ,RV>F_
* @author Joa Q7amp:JFb
*/ A":=-$)
publicclass UserManagerImpl implements UserManager { E2|M#Y
qFVZhBC
private UserDAO userDAO; LYAGpcG
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/** L1_O!EQ
* @param userDAO The userDAO to set. !I|_vJ@<
*/ mN-O{k0\
publicvoid setUserDAO(UserDAO userDAO){
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this.userDAO = userDAO; a|TUH+|
} rHk(@T.]
F=&,=r'Q8
/* (non-Javadoc) aGWO3Nk
* @see com.adt.service.UserManager#listUser h0-.9ym
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(org.flyware.util.page.Page) <e&v[
*/ )4o8SF7lz
public Result listUser(Page page)throws DK2Wjr;
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HibernateException, ObjectNotFoundException { "r`2V-E
int totalRecords = userDAO.getUserCount(); `?T::&`
if(totalRecords == 0) Qraq{'3
throw new ObjectNotFoundException t(<k4 ji,
Obu 6k[BE.
("userNotExist"); Lww&[|k.
page = PageUtil.createPage(page, totalRecords); }2Ge??!
List users = userDAO.getUserByPage(page); "#36-
returnnew Result(page, users); ZC$u8$+P
} {Mo[C%
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} |0^IX
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I+Y Z+
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询,接下来编写UserDAO的代码: >;G7ty[RX7
3. UserDAO 和 UserDAOImpl: "1dpv\
java代码: \{(cz/]G/
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hQ)?LPUB
/*Created on 2005-7-15*/ <%4pvn8d?&
package com.adt.dao; ;p,Kq5,l
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import java.util.List; -R$ Q`Xw
"<L9-vb
import org.flyware.util.page.Page; +pv..\
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import net.sf.hibernate.HibernateException; J,h'eY5
JBV
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/** Sw{rNzh%$
* @author Joa _0&U'/cs
*/ OK@yMGz1I
publicinterface UserDAO extends BaseDAO { <0/)v
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9
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publicList getUserByName(String name)throws _Fkb$NJ"]Q
gxDyCL$h3
HibernateException; 3! KyO)8
(^ J2(
publicint getUserCount()throws HibernateException; UHI<8o9
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publicList getUserByPage(Page page)throws 0LWV.OIIC
\O>;,(>i
HibernateException; BgsU:eKe
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} =EHKu|rX~
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java代码: g s%[Cv
GSGaYq
6(B[(Af
/*Created on 2005-7-15*/ Z(ToemF)hi
package com.adt.dao.impl; D'Kiy
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import java.util.List; 9+'*
z7JhS|
import org.flyware.util.page.Page; _BND{MsX
!$0ozDmD
import net.sf.hibernate.HibernateException; g0s*4E
import net.sf.hibernate.Query; 8J0#lu
o|1_I?_
import com.adt.dao.UserDAO; wEix 8Ow*
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/** ;+~Phdy
* @author Joa i7O8f^|
*/ $btk48a 7
public class UserDAOImpl extends BaseDAOHibernateImpl ^}Gu'!z9D
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implements UserDAO { DLEHsbP{$
9t{Iv({6p
/* (non-Javadoc) u:}yE^8 @
* @see com.adt.dao.UserDAO#getUserByName O<+x=>_
9{R88f?;
(java.lang.String) 7HQ|3rt
*/ ~ll+/w\4
publicList getUserByName(String name)throws 4u]>$?X1_
,Y27uey{wa
HibernateException { =R||c
String querySentence = "FROM user in class cD9axlJ
NfXEW-
com.adt.po.User WHERE user.name=:name"; aeTVcq
Query query = getSession().createQuery ka| 8 _C^z
w*IDL0#
(querySentence); VuA)Ye
query.setParameter("name", name); |BE`ASW;
return query.list(); ;c0z6E /
} -<@QR8:
Y2P%0
/* (non-Javadoc) fqD1Ej
* @see com.adt.dao.UserDAO#getUserCount() Yi#U~ h
*/ s )V<dm;T
publicint getUserCount()throws HibernateException { DBZ^n9
int count = 0; 4
JDk()
String querySentence = "SELECT count(*) FROM nrRP1`!]T
//-;uEO
user in class com.adt.po.User"; vC%8-;8{H
Query query = getSession().createQuery sB%QqFRP
*waaM]u
(querySentence); N Uo
count = ((Integer)query.iterate().next (@;=[5+
@hj5j;NHK
()).intValue(); q;=! =aRg
return count; /nVGr]t_pj
} u%I |o s]
hScC<=W
/* (non-Javadoc) ^*_|26
* @see com.adt.dao.UserDAO#getUserByPage Zp
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>}6V=r3[+
(org.flyware.util.page.Page) &u~#bDh
*/ y8CH=U[
publicList getUserByPage(Page page)throws b*W01ist
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HibernateException { KkD&|&!Q7u
String querySentence = "FROM user in class
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)lDmYt7me
com.adt.po.User"; s>1Wjz2M
Query query = getSession().createQuery "6
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(querySentence); O[<0\
query.setFirstResult(page.getBeginIndex()) \9`76*X6
c
.setMaxResults(page.getEveryPage()); }>< v7
return query.list(); u5E\wRn
} { bD:OF
v2;'F
} M
sQ>eSk
RSK5 }2
~"}o^#@DwJ
o#=@!m
HGl.dO7NU
至此,一个完整的分页程序完成。前台的只需要调用 ~zph,bk
gjDxgNpa
userManager.listUser(page)即可得到一个Page对象和结果集对象 cPbAR'
^&Wa?
m.
的综合体,而传入的参数page对象则可以由前台传入,如果用 iTIYq0u|#R
ZYo?b"6A
webwork,甚至可以直接在配置文件中指定。 ?`T-A\A=
wjc&