Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Jt=->
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Jy)=TJ!y
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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 F
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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 Byc;r-Q5V
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分页支持类: )8A.Wg4S;c
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java代码:
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package com.javaeye.common.util; uO]D=Z\S(
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import java.util.List; },8|9z#pyB
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publicclass PaginationSupport { @P7'MiP]K
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publicfinalstaticint PAGESIZE = 30; `
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privateint pageSize = PAGESIZE; ,Vi_~b
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privateList items; .b,\.0N
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privateint totalCount; j2D!=PK;
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privateint[] indexes = newint[0]; 05 6K) E
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privateint startIndex = 0; =FzmifTc
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public PaginationSupport(List items, int P8YnKyI,.
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totalCount){ `j{3|C=
setPageSize(PAGESIZE); -dM~3'
setTotalCount(totalCount); jr`T6!\
setItems(items); SD^::bH
setStartIndex(0); BbX$R`f
} .4a|^ vT
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public PaginationSupport(List items, int w:
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totalCount, int startIndex){ 5S4Nx>
setPageSize(PAGESIZE); X?haHM#]
setTotalCount(totalCount); /R B%m8@;
setItems(items); %`bs<ZWT
setStartIndex(startIndex); ;-1KPDIp`
} dzIBdth
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public PaginationSupport(List items, int %72# tY
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totalCount, int pageSize, int startIndex){ ~aotV1"D
setPageSize(pageSize); #X)DFAtb
setTotalCount(totalCount); 9BakxmAc
setItems(items); \*MZ1Q*x
setStartIndex(startIndex); L"YQji!
} <W!T+sMQj
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publicList getItems(){ vVB WhY]
return items; O.dZ3!!+
} !*c%Dj
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publicvoid setItems(List items){ A5R"|<UPR
this.items = items; 46f-po_
} ?.,F3@W "
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publicint getPageSize(){ ]4O!q}@Cd
return pageSize; ar@,SKU'K
} w8+phN(-M
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publicvoid setPageSize(int pageSize){ ~Xx}:@Ld
this.pageSize = pageSize; S>5w=RK
} *fY*Wy9
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publicint getTotalCount(){ bSTori5
return totalCount; -n@,r%`UK
} tuH#Cy
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publicvoid setTotalCount(int totalCount){ &4wSX{c/P
if(totalCount > 0){ +sx(q@
this.totalCount = totalCount; &(<Gr0
int count = totalCount / Mprn7=I{Tg
*vNAm(\N
pageSize; [Qr_0O
if(totalCount % pageSize > 0) vmxS^_I
count++; ^E,
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indexes = newint[count]; ]Y,V)41gCE
for(int i = 0; i < count; i++){ 1^AQLOiRE1
indexes = pageSize * yu#m6K
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i; 1&h\\&ic
} nVpDjUpN
}else{ wI7.M
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this.totalCount = 0; M\ wCZG
}
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} Ozqh Jb
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publicint[] getIndexes(){ Wu,=jL3?$A
return indexes; #Hy9 ;Q
} f/
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publicvoid setIndexes(int[] indexes){ UnDX .W*2
this.indexes = indexes; ;qzn_W
} XcbEh
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publicint getStartIndex(){ (;Bh7Ft
return startIndex; 6=%\@
} 2UR1T~r
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publicvoid setStartIndex(int startIndex){ "SuG6!k3
if(totalCount <= 0) _+}o/449
this.startIndex = 0; 2(Xu?W 7d
elseif(startIndex >= totalCount) !FK)iQy$0
this.startIndex = indexes (Rs;+S
&/Gf@[
[indexes.length - 1]; 9r:|u:i7m
elseif(startIndex < 0) 3W[||V[r]<
this.startIndex = 0; \0*dKgN
else{ _+Z;pt$C
this.startIndex = indexes H H3Z?g
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[startIndex / pageSize]; 4<EC50@.
} {Zs
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} njNqUo>
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publicint getNextIndex(){ (\'lV8}U
int nextIndex = getStartIndex() + E.B6u, Te
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pageSize; 75h]#k9\
if(nextIndex >= totalCount)
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return getStartIndex(); M )v='O<H8
else Z@ec}`UO|u
return nextIndex; fHuWBC_YO
} un`4q-S7
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publicint getPreviousIndex(){ HKC&grp
int previousIndex = getStartIndex() - juWbd|ad"
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pageSize; <\d`}A:&
if(previousIndex < 0) C
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return0; 1vh[sKv9%
else ZlMS=<hgFx
return previousIndex; 6m:$RW
} p`"Ic2xPJ
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} x=W5e
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抽象业务类 z2A,*|I
java代码: 9+Wf*:*EW
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/** 1#zD7b~
* Created on 2005-7-12 i\>?b)a>
*/ ^= kr`5
package com.javaeye.common.business; '~{kR=+
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import java.io.Serializable; 4?_^7(%p
import java.util.List; R<r,&X?m
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import org.hibernate.Criteria; 7?y([i\y
import org.hibernate.HibernateException; =QwT)KRB%
import org.hibernate.Session; dA#'HMh@
import org.hibernate.criterion.DetachedCriteria; Nc^:v/(P
import org.hibernate.criterion.Projections; }+:X= @Z@
import 7Zft]C?|@
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org.springframework.orm.hibernate3.HibernateCallback; x45F-w{
import wF-H{C'
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org.springframework.orm.hibernate3.support.HibernateDaoS "`KT7
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upport; 0,cU^HMA
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import com.javaeye.common.util.PaginationSupport; d(vt0
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public abstract class AbstractManager extends Ih5CtcE1'd
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HibernateDaoSupport { 1_mqPMm
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privateboolean cacheQueries = false; )'/xNR
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privateString queryCacheRegion; cf\GC2+"^$
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publicvoid setCacheQueries(boolean _!yUr5&,Br
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cacheQueries){ S;u2B_/
this.cacheQueries = cacheQueries; -;YhQxxC}L
} h\6 t\_^\
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publicvoid setQueryCacheRegion(String Q^'xVS_.
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queryCacheRegion){ >=Na, D
this.queryCacheRegion = Ibv`/8xh
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queryCacheRegion; qjN*oM,
} ;YrmT9Jx6
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publicvoid save(finalObject entity){ 9$ixjkIg
getHibernateTemplate().save(entity); F>k/;@d
} =_$Hn>vO
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publicvoid persist(finalObject entity){ Upc_"mkI.
getHibernateTemplate().save(entity); &8JK^zQq
} Go7 oj'"
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publicvoid update(finalObject entity){ 2}9M7Z",2
getHibernateTemplate().update(entity); As|e=ut(
} i@ehD@.dH
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publicvoid delete(finalObject entity){ R E9`T
getHibernateTemplate().delete(entity); %d0BQ|
} }n k[WW
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publicObject load(finalClass entity, WFfn:WSWU
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finalSerializable id){ <SSkCw
return getHibernateTemplate().load r_Pi)MPc
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(entity, id); 5?>ES*
} >UXNR`?
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publicObject get(finalClass entity, x.q "FXu
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finalSerializable id){ Pu,2a+0N
return getHibernateTemplate().get 3
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(entity, id); 7J|nqr`>t
} ]4,eCT
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publicList findAll(finalClass entity){ ugs9>`fF&
return getHibernateTemplate().find("from L1QDA}6?_Y
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" + entity.getName()); rouaT
} $nNCBC=
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publicList findByNamedQuery(finalString j;EH[3
}(9ZME<(
namedQuery){ KAnq8B!h
return getHibernateTemplate (JT
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().findByNamedQuery(namedQuery); 7DWGYvv[
} 8Q73h/3
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publicList findByNamedQuery(finalString query, ZDm Y${J
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finalObject parameter){ bg^<e}{<H
return getHibernateTemplate z6 .^a-sU5
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().findByNamedQuery(query, parameter); T1(*dVU?
} CEBa,hp@
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publicList findByNamedQuery(finalString query, 2u(G:cR
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finalObject[] parameters){ 7Q?^wx
return getHibernateTemplate a2eE!I
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().findByNamedQuery(query, parameters); &W*^&0AV
} nNh5f]]
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publicList find(finalString query){ pz]!T'
return getHibernateTemplate().find |u+!CR
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(query); 9u%(9Ae
} Dv~jVI Xu
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publicList find(finalString query, finalObject !1/F71l DX
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parameter){ ]l,,en5V
return getHibernateTemplate().find KY\=D 2m
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(query, parameter); +tJ 7ZR%
} dd*p_4;
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public PaginationSupport findPageByCriteria I5ZM U
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(final DetachedCriteria detachedCriteria){ xL"O~jTS
return findPageByCriteria t$rla_rbY
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \t)`Cp6,[b
} /|isRh|
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public PaginationSupport findPageByCriteria 9T0g%&
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(final DetachedCriteria detachedCriteria, finalint #@F.wV0
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startIndex){ %a!gN
return findPageByCriteria %Rk DR
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(detachedCriteria, PaginationSupport.PAGESIZE, Z{ 1B:aW
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startIndex); BlqISyrY
} c7RQ7\
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public PaginationSupport findPageByCriteria my#\(E+
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(final DetachedCriteria detachedCriteria, finalint Zpz3?VM(
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pageSize, [pInF
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finalint startIndex){ *D.Ajd.G
return(PaginationSupport) `@#rAW D
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getHibernateTemplate().execute(new HibernateCallback(){ nlA:C>=
publicObject doInHibernate ',/2J0_
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(Session session)throws HibernateException { $=) Pky-~
Criteria criteria = kT:I.,N
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detachedCriteria.getExecutableCriteria(session); O&,8X-Ix
int totalCount = JfmYr47Pv
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((Integer) criteria.setProjection(Projections.rowCount \>X!n2rLZe
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()).uniqueResult()).intValue(); h}kJ,n
criteria.setProjection -gUp/#l1
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(null); -+0kay%
List items = $m A2AI
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criteria.setFirstResult(startIndex).setMaxResults b`@J"E}
bc3`x1)\^
(pageSize).list(); Ej1<T,w_
PaginationSupport ps = dFyGI?
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new PaginationSupport(items, totalCount, pageSize, Sa
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startIndex); =[LorvX+
return ps; 216$,4i
} N1B$z3E*
}, true); 9Vo*AK'&U
} 8:>V'j
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public List findAllByCriteria(final SMzq,?-`
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DetachedCriteria detachedCriteria){ Hq!|r8@6
return(List) getHibernateTemplate *ifz@8C }
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().execute(new HibernateCallback(){
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publicObject doInHibernate :q?#$?
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(Session session)throws HibernateException { "%\hDL;
Criteria criteria = 57-Hx;
*l=(?Pe<
detachedCriteria.getExecutableCriteria(session); Eku9u
return criteria.list(); Pc2!OQC'""
} UtP|<]{
}, true); -Jw4z#/-
} ,[)l>!0\H
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public int getCountByCriteria(final gn&Zt}@[
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DetachedCriteria detachedCriteria){ v?Utz~lQ
Integer count = (Integer) .6xMLo,R
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getHibernateTemplate().execute(new HibernateCallback(){ Q$v00z]f*
publicObject doInHibernate ~f[ Y;
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(Session session)throws HibernateException { igW* {)h3
Criteria criteria = -%@ah:iJ
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detachedCriteria.getExecutableCriteria(session); ],k~t5+
return 7eAV2.
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criteria.setProjection(Projections.rowCount ~> Q9
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()).uniqueResult(); 9)NKI02M|
} EK Vcz'w
}, true); 0%dOi
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return count.intValue(); Kk6=61} A
} 1^^8,.'
} v"W*@7<`S
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用户在web层构造查询条件detachedCriteria,和可选的 brs`R#e \
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7HBf^N.
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PaginationSupport的实例ps。 FK593z
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ps.getItems()得到已分页好的结果集 849,1n^
ps.getIndexes()得到分页索引的数组 :C(/yg
ps.getTotalCount()得到总结果数 j~G(7t
ps.getStartIndex()当前分页索引 rpK&OR/
ps.getNextIndex()下一页索引 )N8bOI
ps.getPreviousIndex()上一页索引 h]s~w
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 T7.Iqw3p
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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 Z17b=xJw
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一下代码重构了。 Y~85Z0l
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我把原本我的做法也提供出来供大家讨论吧: Y=O+d\_W
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首先,为了实现分页查询,我封装了一个Page类: Q(nTL WW
java代码: q.`<q
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/*Created on 2005-4-14*/ KE~Q88s
package org.flyware.util.page; YHQ]]#'
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/** dAx
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* @author Joa i[IFD]Xy!j
* Lo{wTYt:J
*/
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publicclass Page { )>:~XA|?
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/** imply if the page has previous page */
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privateboolean hasPrePage; Ee2P]4_d
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/** imply if the page has next page */ dX cbS<
privateboolean hasNextPage; <@KIDZYC
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/** the number of every page */ MmN{f~Kq9
privateint everyPage; #0aBQ+_8H
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/** the total page number */ tr[}F7n9
privateint totalPage; X$we\t
# dUKG8-HJ
/** the number of current page */ {MUiK5:
privateint currentPage; e"%TU
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/** the begin index of the records by the current ]EX6Y
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query */ kg]6q T;Y
privateint beginIndex; J 7R(X
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/** The default constructor */ _w4G|j$C
public Page(){ @/.#
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} MONX&$
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/** construct the page by everyPage Y0 a[Lb0
* @param everyPage ?l/6DT>e
* */ Q:(mK* _
public Page(int everyPage){ Bdw33z*m
this.everyPage = everyPage; PlzM`g$A
} ^[xcfTN
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/** The whole constructor */ *=!e,
public Page(boolean hasPrePage, boolean hasNextPage, .P)lQk\
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int everyPage, int totalPage, 8@m$(I+
int currentPage, int beginIndex){ eUA]OF@
this.hasPrePage = hasPrePage; >o?v[:u*
this.hasNextPage = hasNextPage; 4f[%Bb
this.everyPage = everyPage; 3Tl<ST\
this.totalPage = totalPage; \9VF)Y.ke
this.currentPage = currentPage; Q6qW?*Y
this.beginIndex = beginIndex; (4+P7Z,Nc
} E{|B&6$[}
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/** qgrJi +WZ
* @return U|}
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* Returns the beginIndex. VV$t*9w
*/ ,/{e%J
publicint getBeginIndex(){ {JgY-#R?{(
return beginIndex; gm-[x5O"
} WPL@v+
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/** }L_YpG7
* @param beginIndex Lb/GL\J)
* The beginIndex to set. p@Y=6 Bw
*/ 'E_~|C
publicvoid setBeginIndex(int beginIndex){
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this.beginIndex = beginIndex; t5-O-AI[b{
} B}iEhWO6
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/** SndR:{
* @return ODxZO3
* Returns the currentPage. 'k,2*.A
*/ Q1,sjLO-a
publicint getCurrentPage(){ YExgUE|
return currentPage; l^lb ^"o
} M|*YeVs9#
7)lEZJK&T
/** m-Eh0Zl>Z
* @param currentPage dz_S6o ]
* The currentPage to set. R*[sO*h\k
*/ =fcg4h5(
publicvoid setCurrentPage(int currentPage){ KxkBP/`3Q
this.currentPage = currentPage; yq%5h[M
} O(T5
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/** 4@PA+(kvS
* @return Xqf,_I=V
* Returns the everyPage. |THpkfW
*/ :o'x?]
publicint getEveryPage(){ o!M8V ^vW
return everyPage; 4Z)s8sD KW
} ~bLx2=-"
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/** )'djqpM.
* @param everyPage %k!CjW3
* The everyPage to set. a`!Jq'
*/ "n%s>@$
publicvoid setEveryPage(int everyPage){ 1t
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this.everyPage = everyPage; !"L.g u-'
} m{/7)2.
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/** f<YYo
* @return $h#sb4ek
* Returns the hasNextPage. }Pcm'o_wT
*/ Og\k5.! ,
publicboolean getHasNextPage(){ 9bM\ (s/
return hasNextPage; <Riz!(G
} 5C Dk5B_
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/** F$7!j$
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* @param hasNextPage _'=,c"
* The hasNextPage to set. 40t xZFQ0
*/ (\AN0_
publicvoid setHasNextPage(boolean hasNextPage){ --5F*a{R|
this.hasNextPage = hasNextPage; [l23b{
} q(KjhM
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/** 3Ua?^2l
* @return l(t&<O(m9
* Returns the hasPrePage. ~t6q-P
*/ $^]K611w9
publicboolean getHasPrePage(){ =Hi@q
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return hasPrePage; ^hIdmTf6
} Z8|<%1Kge
}v ZOPTP
/** |mEWN/@C
* @param hasPrePage ,Bk5(e
* The hasPrePage to set. ]~TsmR[
*/ XNz+a|cF
publicvoid setHasPrePage(boolean hasPrePage){ "aJHCi~l
this.hasPrePage = hasPrePage; UL+Txc
} 6D;N.wDZ
p*
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/** }3(!kW
* @return Returns the totalPage. )Qbd/zd\U
* owAO&"C
*/ }p)K6!J0
publicint getTotalPage(){ @oXGa>Ru
return totalPage; Y}?8
} ula-o)S
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/** 5UEZpxnv
* @param totalPage /v{+V/'+
* The totalPage to set. qN!oN*
*/ 9zp!lw~;+
publicvoid setTotalPage(int totalPage){ &,nv+>D
this.totalPage = totalPage; wI%M3XaBws
} B8@mL-Z-;
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} S6~y!J6Ok4
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 3lP;=*m.
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个PageUtil,负责对Page对象进行构造: feej'l }F
java代码: 2dn^K3
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/*Created on 2005-4-14*/ 3c<aI=$^
package org.flyware.util.page; 78&|^sq
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import org.apache.commons.logging.Log; U&^q#['
import org.apache.commons.logging.LogFactory; )jM%bUk,!
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/** -Jd|H*wWo
* @author Joa )qWwh)\;!
* pKSCC"i&j
*/ vW+6_41ZM
publicclass PageUtil { `ecseBn3d
({uW-%
privatestaticfinal Log logger = LogFactory.getLog @v-^j
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(PageUtil.class); PgBEe
@.
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/** vX+oZj
* Use the origin page to create a new page DX_mrG
* @param page e(c\ U}&
* @param totalRecords y{<e4{
!
* @return !<[+u
*/ Xoj"rR9|
publicstatic Page createPage(Page page, int !>`Q]M`
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totalRecords){ ",#.?vT`
return createPage(page.getEveryPage(), sx,$W3zI'G
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page.getCurrentPage(), totalRecords); &^=Lr:I
} 3smkY
T4eJ:u* ;
/** I68u%fCv
* the basic page utils not including exception Y{Z&W9U
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handler BQu
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* @param everyPage o[C^z7WG0
* @param currentPage r%,?uim#
* @param totalRecords {R1]tGOf
* @return page rOJ>lPs
*/ Y=S0|!u
publicstatic Page createPage(int everyPage, int 5KCQvv\
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currentPage, int totalRecords){ yD9enYM
everyPage = getEveryPage(everyPage); Liqo)m
currentPage = getCurrentPage(currentPage); bt}8ymcG
int beginIndex = getBeginIndex(everyPage, >* -IIo
9b.
kso9.
currentPage); DUOoTlp
int totalPage = getTotalPage(everyPage,
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totalRecords); x9lA';})
boolean hasNextPage = hasNextPage(currentPage, AL]gK)R
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totalPage); QV|6"4\
boolean hasPrePage = hasPrePage(currentPage); *D]:{#C*
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returnnew Page(hasPrePage, hasNextPage, Q'<AV1<
everyPage, totalPage, .S` q2C\
currentPage, :V/".K-:J
}">r0v!3
beginIndex); Ycr3$n]e
} VU3RFl
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privatestaticint getEveryPage(int everyPage){ mxlh\'b
return everyPage == 0 ? 10 : everyPage; +t!]nE#
} zIa={tU
x'|ty[87
privatestaticint getCurrentPage(int currentPage){ |<W$rzM
return currentPage == 0 ? 1 : currentPage; axQ>~vWN/
} 2?,Jn&i5
xm m,-u
privatestaticint getBeginIndex(int everyPage, int Tmg C {_
r)<A YX]J
currentPage){ OUv )`K
return(currentPage - 1) * everyPage; P\"kr?jZP
} v93b8/1
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privatestaticint getTotalPage(int everyPage, int !HTOE@
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totalRecords){ 9o@3$
int totalPage = 0; V,r~%p
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if(totalRecords % everyPage == 0) \Ec<ch[)c
totalPage = totalRecords / everyPage; sI,cX#h&Y
else tU4#7b:Y
totalPage = totalRecords / everyPage + 1 ; =!TUf/O-
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return totalPage; f)sy-o!
} .; MS78BR
1RAkqw<E
privatestaticboolean hasPrePage(int currentPage){ ]d*9@+Iu
return currentPage == 1 ? false : true; ^ :VH?I=
} 5/.W-Q\pl}
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privatestaticboolean hasNextPage(int currentPage, `KQx#c>'
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int totalPage){ 86#l$QaK{
return currentPage == totalPage || totalPage == LnR>!0:c
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0 ? false : true; ^O}a,
} =2!p>>t,d;
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} z5@XFaQ
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Sca"LaW1
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面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 w:\} B'u
!5,C"r
做法如下: ~RR!~q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ':.Hz]]/A
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的信息,和一个结果集List: Jv}
java代码: {!Qu(%
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/*Created on 2005-6-13*/ M`Y^hDl 6
package com.adt.bo; Nj9A-*0g6N
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import java.util.List; !Fl'?Kz
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import org.flyware.util.page.Page; 12`u[O}\}-
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/** 3Gs\Q{O:
* @author Joa 3?o4
*/ 2@S}x@^
publicclass Result { (Yewd/T
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private Page page; ~kW?]/$h
+tPBm{|
private List content; xs= ~N
uw mN!!TS
/** rXB;#ypO
* The default constructor 9=>q0D2
*/ :^7w
public Result(){ ZvRa"j
super(); JxIJxhA>
} W9SU1{*9
0? {ADQz
/** 4*EMd!E=<
* The constructor using fields ,YD7p= PY
* kjYM&q
* @param page +O/b[O'0
* @param content 2^r~->
*/ 5FOMh"!z\
public Result(Page page, List content){ s#?ZwD,=
this.page = page; sK2N3B&6
this.content = content; -6[DQB
}
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/**
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* @return Returns the content.
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*/ REW[`MBQ
publicList getContent(){ 2U)n^
return content; !q\8`ss
} d:)#-x*h7
@7 Ry{,A
/** kcfT|@:MK"
* @return Returns the page. bYsX?0T!p
*/ Y4k2=w:D
public Page getPage(){ T;6M UmyC
return page; ?.e,NHf
} t/;2rIx>
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/** XPd mz !,b
* @param content kqBZsfF
* The content to set. U3_${
*/ xF8r+{_J)
public void setContent(List content){ &M13F>!
this.content = content; V\`Z|'WIQD
} W,4!"*+
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/** ^_]ZZin
* @param page +d3|Up8=
* The page to set.
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*/ A3eCI
publicvoid setPage(Page page){ {lf{0c$X.
this.page = page; k%6CkCw
} :a }](Wn
} TUfj\d,
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2. 编写业务逻辑接口,并实现它(UserManager, 1_+ h"LE
2>o[
UserManagerImpl) *2h%dT:,%
java代码: G4(R/<J,BQ
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/*Created on 2005-7-15*/ -Q20af-
package com.adt.service; 1'&.6{)P
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import net.sf.hibernate.HibernateException; s+:|b~
n\+c3
import org.flyware.util.page.Page; afrF%!
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import com.adt.bo.Result; w9'>&W8T
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/** *qzdt^[ xo
* @author Joa zxn|]PbS
*/ ep6+YK:cn
publicinterface UserManager { 1GYZ1iA
x?L[*N_ml
public Result listUser(Page page)throws FJ3S
@1*^ttC
HibernateException; 3L&:
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} 7${<u 0((!
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java代码: 6=f)3!=
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/*Created on 2005-7-15*/ Wk[a|>
package com.adt.service.impl; BgXZr,?
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import java.util.List; Kn^+kHh:
C~2!@<y
import net.sf.hibernate.HibernateException; {T8;-H0H
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import org.flyware.util.page.Page; 9"P+K.%
import org.flyware.util.page.PageUtil; ;+~5XLk
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import com.adt.bo.Result; Em!- W5*s
import com.adt.dao.UserDAO; E&8Nh J
import com.adt.exception.ObjectNotFoundException; )Q=u[ p
import com.adt.service.UserManager; _*AI1/>`
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/** j:%,lcF
* @author Joa cy^=!EfA
*/ }2]|*?1,
publicclass UserManagerImpl implements UserManager { =F@
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*H/>96
private UserDAO userDAO; xeF>"6\
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/** `PARZ|
* @param userDAO The userDAO to set. E^)FnXe5
*/ 'iW
publicvoid setUserDAO(UserDAO userDAO){ .?u<|4jE6
this.userDAO = userDAO; iYr)Ao5X
} lrE"phYk
TdPd8ig8{
/* (non-Javadoc) RiTL(Yx
* @see com.adt.service.UserManager#listUser K$Bv4_|x
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(org.flyware.util.page.Page) `Wx|
4
*/ $UzSPhv[
public Result listUser(Page page)throws EGl<oxL*R2
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HibernateException, ObjectNotFoundException { M@T{uo
int totalRecords = userDAO.getUserCount(); as@8L|i*
if(totalRecords == 0) qxI$F
throw new ObjectNotFoundException ?-j/X6(\(
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("userNotExist"); +<Gp >c
page = PageUtil.createPage(page, totalRecords); ^0zfQu+!
List users = userDAO.getUserByPage(page); 5'set?
returnnew Result(page, users); |&4A"2QN
} 7L
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} jj`#;Y
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 6)1PDlB
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询,接下来编写UserDAO的代码: OkC.e')Vx
3. UserDAO 和 UserDAOImpl: vhF9|('G
java代码: +JI,6)Ry
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B :%Vq2`
/*Created on 2005-7-15*/ {|oWU8.l
package com.adt.dao; ug,AvHEnB
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import java.util.List; &-*l{"7p+%
]0>
import org.flyware.util.page.Page; 8)S)!2_h
^$'{:i
import net.sf.hibernate.HibernateException; ;?{^LiD+F
+2{ f>KZ
/** rfonM~3?'
* @author Joa - ;gQy[U
*/ '=;e#
C`<{
publicinterface UserDAO extends BaseDAO { F`4W5~`
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publicList getUserByName(String name)throws @A6iY
s={>{,E
HibernateException; KH,f'`
w!"A$+~
publicint getUserCount()throws HibernateException; _jX,1+M
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publicList getUserByPage(Page page)throws 5=V"tQ&d9U
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HibernateException; Tbm
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} #[bosb!R
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java代码: j)/Vtf
jvQ^Vh!mC
|]<#![!h#
/*Created on 2005-7-15*/ !%$[p'
package com.adt.dao.impl; g#i~^4-1
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import java.util.List; WzFXF{(
A!GvfmzqIn
import org.flyware.util.page.Page; CE
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W^09tx/I
import net.sf.hibernate.HibernateException; 07SW$INb
import net.sf.hibernate.Query; ga|<S@u?}
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[
import com.adt.dao.UserDAO; c9c]1XJ
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/** ?8$`GyjS
* @author Joa 3~fi#{
*/ \j!/l
f)
public class UserDAOImpl extends BaseDAOHibernateImpl SOG(&)b
GI{EP&