Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 u+mjguIv
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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 7cUR.PI#Q
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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 Ok}{jwJ%W;
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分页支持类: :jk)(=^
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java代码: {WYu0J@
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package com.javaeye.common.util; GhG%>U#&a
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import java.util.List; Vq3]7l
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publicclass PaginationSupport { KFTf~!|
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publicfinalstaticint PAGESIZE = 30; %w'/n>]j
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privateint pageSize = PAGESIZE; X+dR<GN+YX
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privateList items; i"%JFj_G
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privateint totalCount; }zkL[qu;
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privateint[] indexes = newint[0]; Bmx(qE
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privateint startIndex = 0; w8 ?Pb$Fe
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public PaginationSupport(List items, int qZ8|B
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totalCount){ TJHN/Z/
setPageSize(PAGESIZE); 8%;}LK
setTotalCount(totalCount); <Jwi~I=^
setItems(items); F^.om2V|9
setStartIndex(0); t{/:( Nu
} p!HPp Ef+#
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public PaginationSupport(List items, int vnz[w=U
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totalCount, int startIndex){ Zg)_cRR
setPageSize(PAGESIZE); )ZT6:)
setTotalCount(totalCount); =dgo!k
setItems(items); Q^$ghZ6V
setStartIndex(startIndex); ZhhI@_sz
} zW%>"y
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public PaginationSupport(List items, int %/UV_@x&
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totalCount, int pageSize, int startIndex){ 4=u+ozCG
setPageSize(pageSize); N@k3$+ls
setTotalCount(totalCount); d>lt
setItems(items); +<S9E'gT3V
setStartIndex(startIndex); Wc~3^;U
} &?SX4c~?u
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publicList getItems(){ 8K|J:[7
return items; lbQ6
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} P7's8KOoS
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publicvoid setItems(List items){ yJDeX1+,
this.items = items; /3J z3
} f=t:[<
)
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publicint getPageSize(){ x1t{SQ-C
return pageSize; !cRfZ
} {/-y>sm
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publicvoid setPageSize(int pageSize){ }TSgAwsbC
this.pageSize = pageSize; MVeFe\r
} F(d:t!
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publicint getTotalCount(){ mfZ)^X
return totalCount; ]kRI}Om2
} j*tk(o}qG
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publicvoid setTotalCount(int totalCount){ _~tm7o+js
if(totalCount > 0){ FXS^^p
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this.totalCount = totalCount; cb+l"FI7
int count = totalCount / ^:m^E0(H
p= {Jf}v
pageSize; `-4'/~G
if(totalCount % pageSize > 0) [-4KY4R
count++; :%N*{uy
indexes = newint[count]; wz|DT3"Xs
for(int i = 0; i < count; i++){ z(+&wa
indexes = pageSize * T_eJ}(p
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} /$;,F't#2M
}else{ #S%4?
this.totalCount = 0; X` ATH^S
} uaiz*Im
} <x0)7xX
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publicint[] getIndexes(){ 4avc=Y5
return indexes; M ~als3
} b 8>q;
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publicvoid setIndexes(int[] indexes){ @|BD|{k
this.indexes = indexes; uG;?vvg>
} 4:D:| r
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publicint getStartIndex(){ b \:~ ;
return startIndex; ZP-dW|<[x
} !K[/L<
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publicvoid setStartIndex(int startIndex){ lK*jhW?3:
if(totalCount <= 0) fmFzW*,E
this.startIndex = 0; S.: 7k9
elseif(startIndex >= totalCount) 6JSY56v
this.startIndex = indexes P'sfi>A
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[indexes.length - 1]; E4r.ky`#~
elseif(startIndex < 0) I FsE!oDs4
this.startIndex = 0;
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else{ H8&p<=
this.startIndex = indexes A;,Dg=FL/
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[startIndex / pageSize]; j9:/RJS
} qbb6,DL7J
} 34z+INkX
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publicint getNextIndex(){ I+|uUg5
int nextIndex = getStartIndex() + }%$OU = T
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pageSize; 09d9S`cS\
if(nextIndex >= totalCount) <#y*h8IZ@t
return getStartIndex(); wX0l?xdI
else _8^0!,j
return nextIndex; Q ]"jD#F
} =2%VZE7Vm
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publicint getPreviousIndex(){ v5T`K=qC
int previousIndex = getStartIndex() - \,R!S /R#
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pageSize; F;P5D<
if(previousIndex < 0) -IU4#s
return0; mw4JQ\
else -w]/7cH
return previousIndex; P$ucL~r
} O#EqG.L5
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} :3^dF}>
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抽象业务类 {E51Kv&_
java代码: ;1`!wG-DD
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/** V&*D~Jq
* Created on 2005-7-12
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*/ &yU>2=/T
package com.javaeye.common.business; IP ,.+:i
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import java.io.Serializable; qSTW b%
import java.util.List; rslvsS:
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import org.hibernate.Criteria; c<4F4k7
import org.hibernate.HibernateException; ?Vc0)
import org.hibernate.Session; VI_+v[Hk/
import org.hibernate.criterion.DetachedCriteria; ]
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import org.hibernate.criterion.Projections; 6+3 $:?
import "|t!7hC
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org.springframework.orm.hibernate3.HibernateCallback; {<K=*rrZ
import 9x?'}
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org.springframework.orm.hibernate3.support.HibernateDaoS ?:igumeYX
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upport; Wp[9beI*M
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import com.javaeye.common.util.PaginationSupport; ?pG/m%[
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public abstract class AbstractManager extends .'T 40=7
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HibernateDaoSupport { 3-|3`(
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privateboolean cacheQueries = false; OJ1tV% E
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privateString queryCacheRegion; zvO:"w}
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publicvoid setCacheQueries(boolean SK
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cacheQueries){ Td h TQ
this.cacheQueries = cacheQueries; }mk>!B}=
} y=Q!-~5|fF
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publicvoid setQueryCacheRegion(String cWa)#:JOV
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queryCacheRegion){ cyQBqG
this.queryCacheRegion = =a$Oecg?
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queryCacheRegion; mgQIhXH5L
} vzXag*0
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publicvoid save(finalObject entity){ %8r/oS
getHibernateTemplate().save(entity); hXB|g[zT
} .L EY=j!-s
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publicvoid persist(finalObject entity){ y1pu R7
getHibernateTemplate().save(entity); .=c<>/
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} *Y6xvib9*
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publicvoid update(finalObject entity){ Vrkf(E3_V
getHibernateTemplate().update(entity); ,
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} (=
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publicvoid delete(finalObject entity){ Y;
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getHibernateTemplate().delete(entity); %j+xgX/&
} KzO,*M
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publicObject load(finalClass entity, 27A!\pn
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finalSerializable id){ -VT+O+9_A
return getHibernateTemplate().load *%gF2@=r8F
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(entity, id); ;\{`Ci\
} f_=~H<j!
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publicObject get(finalClass entity, "%6/a7S
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finalSerializable id){ V diJ>d[
return getHibernateTemplate().get #FH[hRo=6
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(entity, id); s?C&s|'.
} -e]7n*}H$
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publicList findAll(finalClass entity){ IV `%V+
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return getHibernateTemplate().find("from D(]E/k@;~
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" + entity.getName()); \6!W05[ Q
} A1i!F?X
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publicList findByNamedQuery(finalString z(13~38+
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namedQuery){ z rfUQO
return getHibernateTemplate 6'-As=iw
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().findByNamedQuery(namedQuery); =E*Gb[r_7
} s!B/WsK
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publicList findByNamedQuery(finalString query, nH-V{=**
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finalObject parameter){ # Su~`]
return getHibernateTemplate Zjh2{ :
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().findByNamedQuery(query, parameter); ,5Vt]#F5@
} jp2Q9Z
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publicList findByNamedQuery(finalString query, s^8u&y)3
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finalObject[] parameters){ \cJa;WM>
return getHibernateTemplate PkuTg";
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().findByNamedQuery(query, parameters); `'S0*kMT
} 9 ;i\g=
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publicList find(finalString query){ %;xOB^H^
return getHibernateTemplate().find /~p+j{0L3W
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(query); {w6/[-^
} `Ityi}
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publicList find(finalString query, finalObject OQ&'Dti
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parameter){ ` uCI Xb
return getHibernateTemplate().find {FO$yw=>
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(query, parameter); rf&M!d}!
} %3r:s`{
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public PaginationSupport findPageByCriteria V@-)\RZm
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(final DetachedCriteria detachedCriteria){ )?! [}t
return findPageByCriteria KvFMs\o6p
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); SGL|Ck
} [{u(C!7L`
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public PaginationSupport findPageByCriteria -V.d?A4"
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(final DetachedCriteria detachedCriteria, finalint `{v?6:G:Q
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startIndex){ I0'WOV70
return findPageByCriteria ]b?9zeT*'l
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(detachedCriteria, PaginationSupport.PAGESIZE, ZJW[?V\5=
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startIndex); e.d
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} -e GL) M
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public PaginationSupport findPageByCriteria (.Y/
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(final DetachedCriteria detachedCriteria, finalint y[};J
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pageSize, xgu `Q`~
finalint startIndex){ cf_|nL#9
return(PaginationSupport) x3+oAb@o/
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getHibernateTemplate().execute(new HibernateCallback(){ Hy:V`>
publicObject doInHibernate B5%n(,Lx
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(Session session)throws HibernateException { {V19Zv"j
Criteria criteria = w'4AJ Q|;
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detachedCriteria.getExecutableCriteria(session); W*DVi_\$y
int totalCount = =<@2#E)
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((Integer) criteria.setProjection(Projections.rowCount $lA
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()).uniqueResult()).intValue(); VXBY8;+Yp
criteria.setProjection pO Iq%0]
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(null); 8LkP)]4^sO
List items = IA zZ1#/3
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criteria.setFirstResult(startIndex).setMaxResults ^ >x|z.
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(pageSize).list(); u|#>32kV
PaginationSupport ps = /hrT
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new PaginationSupport(items, totalCount, pageSize, $q?$]k|M`
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startIndex); Dn9w@KO
return ps; ocbB&
} DhLqhME53
}, true); sAn0bX
} w>fdQ!RdP
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public List findAllByCriteria(final ~[o4a '
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DetachedCriteria detachedCriteria){ s.Y4pWd5@
return(List) getHibernateTemplate cLa]D[H
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().execute(new HibernateCallback(){ 5wao1sd#
publicObject doInHibernate )4U>!KrY
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(Session session)throws HibernateException { -{XRA6
Criteria criteria = $0oO
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detachedCriteria.getExecutableCriteria(session); dCe4u<so\
return criteria.list(); 5<pftTcZ
} kv,%(en]
}, true); hVT~~n`Rj
} Jb)#fH$L
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public int getCountByCriteria(final *_ Z#O,
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DetachedCriteria detachedCriteria){ WO4=Mte?
Integer count = (Integer) 9Ya<My
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getHibernateTemplate().execute(new HibernateCallback(){ -4rDbDsr
publicObject doInHibernate kd:$oS_*s
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(Session session)throws HibernateException { SKuIF*"!S
Criteria criteria = )0vU
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detachedCriteria.getExecutableCriteria(session); W!blAkM%i
return mME4 l
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criteria.setProjection(Projections.rowCount 1(zsOeX
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()).uniqueResult(); p^nL&yIW,%
} E9|eu\
}, true); n,HE0Zn]Y_
return count.intValue(); OH^N" L
} <e]Oa$
} q+KzIde|%
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用户在web层构造查询条件detachedCriteria,和可选的 "Td`AuP@,
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 V@7KsB
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PaginationSupport的实例ps。 oRKEJNps
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ps.getItems()得到已分页好的结果集 J89Dul l
ps.getIndexes()得到分页索引的数组 TSAU?r\P
ps.getTotalCount()得到总结果数 ^=n+T7"J
ps.getStartIndex()当前分页索引 @D-AO_
ps.getNextIndex()下一页索引 GLn{s
ps.getPreviousIndex()上一页索引 i&njqK!wS
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 }>^Q'BW;65
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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 )&era` e[
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: VL[R(a6c
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首先,为了实现分页查询,我封装了一个Page类: N=:5eAza
java代码: xD&^j$Em
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/*Created on 2005-4-14*/ SVjl~U-^
package org.flyware.util.page; hjO*~
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/** r1ws1 rr=
* @author Joa 2&+#Vsm`V
* Ggh.dZI4
*/ [Q\GxX.
publicclass Page { v7%X@j]ji
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/** imply if the page has previous page */ #j@71]GI
privateboolean hasPrePage; v+jsC`m
g8!wb{8?s
/** imply if the page has next page */ *lef=:&,,
privateboolean hasNextPage; t}v2$<!I
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/** the number of every page */ @fuM)B1"
privateint everyPage;
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g}p;\o
/** the total page number */ Z~A@o""F
privateint totalPage; {bO|409>W
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/** the number of current page */ e]=!"nJ+
privateint currentPage; 1!pa;$L
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/** the begin index of the records by the current tbnH,*
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query */ fN"(mW>!
privateint beginIndex; ;q0uE:^S
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/** The default constructor */ Z):n c% S
public Page(){ R3k1RE2c&g
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} *9)SmSs
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/** construct the page by everyPage {JV@"t-X3"
* @param everyPage "EU{8b
* */ G/%iu;7ZCb
public Page(int everyPage){ .I}:m%zv
this.everyPage = everyPage; lTU$0CG
} b$k&dT\o
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/** The whole constructor */ _(m't n>
public Page(boolean hasPrePage, boolean hasNextPage, kE
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int everyPage, int totalPage, w&4~Q4
int currentPage, int beginIndex){ Ll MpS<2NO
this.hasPrePage = hasPrePage; 1<ro7A4hK
this.hasNextPage = hasNextPage; X-Wz:NA
this.everyPage = everyPage; GE|+fYVM-$
this.totalPage = totalPage; ~[k%oA%W
this.currentPage = currentPage; UD~p'^.m_
this.beginIndex = beginIndex; $D31Q[p=+
} ?PTk1sB
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/** `nUO l
* @return l"n{.aL
* Returns the beginIndex. Th`skK&U
*/ jlFk@:y4
publicint getBeginIndex(){ &R~n>>c
return beginIndex; qo)?8kx>l
} uP\lCqK,
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/** T]Nu)
* @param beginIndex ?^:h\C^a"
* The beginIndex to set. &D%(~|'
*/ >:=|L%]s;\
publicvoid setBeginIndex(int beginIndex){ (;. AS
this.beginIndex = beginIndex; -C#PQV
} n;R#,!<P
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/** `V[!@b:
* @return iut`7
* Returns the currentPage. 5>J=YLq
*/ Y32O-I!9u
publicint getCurrentPage(){ 4/X/>Y1
return currentPage; ^$%Z!uz
} )Qm[[p nj
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/** M5T9JWbN
* @param currentPage q_
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* The currentPage to set. y]%w )4PS
*/ E&yD8=vw
publicvoid setCurrentPage(int currentPage){ >h Y"
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this.currentPage = currentPage; sBv>E}*R
} 569}Xbc/
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/** +7Kyyu)y@
* @return ( *G\g=D
* Returns the everyPage. M.h`&8
*/ 6)pH|d.FR
publicint getEveryPage(){ w@2Vts
return everyPage; reo{*)%
} C1T_9}L-A
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/** HaA1z}?n
* @param everyPage )hwV`2>l
* The everyPage to set. 7j5f ;O^+
*/ s=?aox7
publicvoid setEveryPage(int everyPage){ X &2oPo
this.everyPage = everyPage; {;2i.m1
} $-+/$!
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/** wPbkUVO
* @return x*oWa,
* Returns the hasNextPage. &iN--~}!$
*/ 79zJ\B_
publicboolean getHasNextPage(){ .@iFa3
return hasNextPage; \qi|Js*{
} ]E3U
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/** m?s}QGSka
* @param hasNextPage # N~,F@t
* The hasNextPage to set. w",?
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*/ G
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publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; ^4%Zvl
} -ZW0k@5g
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/** 0;,IKXK6X
* @return s?WCnT
* Returns the hasPrePage. ()PKw,pD
*/ F2(q>#<_
publicboolean getHasPrePage(){ v;{{ y-
return hasPrePage; Uadr>#C*
} - ~O'vLG
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/** _eLWQ|6Fx
* @param hasPrePage 59(U `X
* The hasPrePage to set. QD{:vG
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*/ `h;k2Se5
publicvoid setHasPrePage(boolean hasPrePage){ lC97_T
this.hasPrePage = hasPrePage; dAJ,x
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} '+<(;2Z
vL
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/** `,wu}F85
* @return Returns the totalPage. PXP`ZLF
* ')+0nPV
*/ O?bK%P]ay
publicint getTotalPage(){ m9M
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return totalPage; jc_\'Gr+[
} 9?+9UlJ7K
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/** UVf\2\ Y
* @param totalPage IL7`0cN(
* The totalPage to set. jW*1E*"
*/ B1N)9%
publicvoid setTotalPage(int totalPage){ ~E4"}n[3A#
this.totalPage = totalPage; oN[Th
} >=ot8%.!,B
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} :lcea6iO
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? y},,
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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 Ft%hh|$5y
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.
个PageUtil,负责对Page对象进行构造: mkvvNm3
java代码: hJ%1
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/*Created on 2005-4-14*/ }{7e7tW6
package org.flyware.util.page; Mjpo1dw
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import org.apache.commons.logging.Log; kD~uGA
import org.apache.commons.logging.LogFactory; Y{Ap80'\6
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/** g+q@i{Yn
* @author Joa E|Bd>G
* $]d*0^J 6
*/ ^Uw[x\%#gD
publicclass PageUtil { p|6v~
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privatestaticfinal Log logger = LogFactory.getLog TZ^LA
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(PageUtil.class); ph30'"[Z}
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/** wN]J8Ir
* Use the origin page to create a new page lhn8^hOJ/
* @param page :,]S}R
* @param totalRecords +KK$0pL
* @return >POO-8Q
*/ f~& a-
publicstatic Page createPage(Page page, int fhpX/WE6
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totalRecords){ o sdOw8
return createPage(page.getEveryPage(), tR`S#rk
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page.getCurrentPage(), totalRecords); gzfb zt}?
} H9"= p
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/** 9$WJ"]
* the basic page utils not including exception =v2%Vs\7k
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handler ]Bu DaxWN
* @param everyPage %&] 1FhL
* @param currentPage M$#sc`4*
* @param totalRecords <,39_#H?F3
* @return page W04av_u 5
*/ P;foK)AM
publicstatic Page createPage(int everyPage, int T`L}[?w
vb =CFV#
currentPage, int totalRecords){ VZxTx0: ,
everyPage = getEveryPage(everyPage); ~^o=a?L`<
currentPage = getCurrentPage(currentPage); v+q<BYq
int beginIndex = getBeginIndex(everyPage, hYt7kq!"
>S&U.
currentPage); wz#[:2
int totalPage = getTotalPage(everyPage, @6.]!U4w
eqzTQen8q
totalRecords); =t+ ('
boolean hasNextPage = hasNextPage(currentPage, _x\m|SF_g
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totalPage); }5S2p@W)
boolean hasPrePage = hasPrePage(currentPage); Dt}dp_
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returnnew Page(hasPrePage, hasNextPage, ;<6"JP>0
everyPage, totalPage, Du_$C[
currentPage, P.4E{.)(
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beginIndex); .j 'wQ+_
} -{x(`9H;
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privatestaticint getEveryPage(int everyPage){ 7>je6*(K
return everyPage == 0 ? 10 : everyPage; #tz8{o?ebN
} o<\6Rm
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privatestaticint getCurrentPage(int currentPage){ "@t-Cy:!O
return currentPage == 0 ? 1 : currentPage;
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} N du7nKG
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privatestaticint getBeginIndex(int everyPage, int )+GX<2_
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currentPage){ f)gGH'yOQ
return(currentPage - 1) * everyPage; 6o
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} kkfCAM
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privatestaticint getTotalPage(int everyPage, int 9".Uc8^p/F
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totalRecords){ +{vQSFW
int totalPage = 0; &q>h*w4O
q!*MH/R
if(totalRecords % everyPage == 0) c,BAa*]K
totalPage = totalRecords / everyPage; j;0ih_Z@4W
else iPFL"v<#J
totalPage = totalRecords / everyPage + 1 ; M7p8^NL
jeFN*r_
return totalPage; 'Kd7l}e!
} `i4I!E
!u0U5>ccw
privatestaticboolean hasPrePage(int currentPage){ [f(uqLdeM
return currentPage == 1 ? false : true; #_p
}
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privatestaticboolean hasNextPage(int currentPage, 7,su f }=
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int totalPage){ G-8n
return currentPage == totalPage || totalPage == rgT%XhUS6f
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0 ? false : true; PdjCv+R6?
} jaa/k@OG
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} Ns~g+C9
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{.#j1r4J`
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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。 5:_~mlfi
bXm:]?
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 g`{Dxb,t
| @q9{h7
做法如下: B{4"$Mi
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xO gq-@`
(WkTQRcN,
的信息,和一个结果集List: a[JZ5D
java代码: 5~-}}F
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C &FN#B
/*Created on 2005-6-13*/ ZU^Q1}</5
package com.adt.bo; A ')(SGSc
q|/!0MU"
import java.util.List; {V=vnL--
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import org.flyware.util.page.Page; Lqq*Nr
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/** M3PVixli3
* @author Joa }kv) IJ
*/ !yk7HaP
publicclass Result { X`tOO
sFD!7;
private Page page; s|KfC>#
D~7%};D[
private List content; y#nSk%"t"
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/** L&rO6
* The default constructor iF+S%aPd#
*/ M Yu?&}%^
public Result(){ WY3_7k8u
super(); U0zW9jB
} UzN8G$92qF
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/** DZF[dxH
* The constructor using fields (c
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* XZ;*>(
* @param page :Z]/Q/$
* @param content 8[f8k3g
*/ @ >
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public Result(Page page, List content){ H2s*s[T
-
this.page = page; $kM'
this.content = content; s%hU*^ 8
} J~fuW?a]r
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/** EF0Pt
* @return Returns the content. fWqv3nY^
*/ <b3x(/
publicList getContent(){ ;cnnqT6
return content; ,q/tyGj
} G)4ZK#wz
ipgN<|`?@
/** B?!9W@
* @return Returns the page. .$n$%|"H-
*/ w
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public Page getPage(){ KC#kss
return page; J,.j_ii`!
} WFQ*s4 R(
q.U*X5
/** !4i,%Z&6
* @param content b*@&c9I;q
* The content to set. 0@JilGk1u
*/ q+r `e
public void setContent(List content){ (ej:_w1
this.content = content; M
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} 5~v(AB(x
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/** 7AS.)Q#=x
* @param page Smi%dp.
* The page to set. XPGL3[w\V
*/ 0EcC
publicvoid setPage(Page page){ t$ACQ*O
this.page = page; aslU`#"
} myEGibhK
} [u,hc/PL
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jdV .{8@
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>_|Z{:z]d.
2. 编写业务逻辑接口,并实现它(UserManager, Q$/V) 0
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UserManagerImpl) ey'pm\Z
java代码: a3b2nAI l
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a!TBk=P
/*Created on 2005-7-15*/ 8<E!rn-
package com.adt.service; 4r68`<mn[
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import net.sf.hibernate.HibernateException; 3ybK6!g`[
BG(R=,
7
import org.flyware.util.page.Page; jh<TdvF2$
,6S_&<{
import com.adt.bo.Result; o|zrD~&$
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/** {mCKTyN+
* @author Joa +#de8/x
*/ 8MYLXW6
publicinterface UserManager { e;&{50VY
CVyx lc>
public Result listUser(Page page)throws X|lElN
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HibernateException; c,3'wnui
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} XvfcPI6
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}a #b$]Y
java代码: !q7;{/QM6
wHBHkz
J]kP`
/*Created on 2005-7-15*/ k"3Z@Px:
package com.adt.service.impl; i5L+8kx4
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import java.util.List; !4qps$p{
mK7^:(<.LO
import net.sf.hibernate.HibernateException; %~~z9 6(
*783xEF>f
import org.flyware.util.page.Page; ,Do$`yO+
import org.flyware.util.page.PageUtil; <ZHY3
.dg 4gr\D
import com.adt.bo.Result; p ?Ij-uo"o
import com.adt.dao.UserDAO; 4acP*LkkQ
import com.adt.exception.ObjectNotFoundException; pR@GvweA
import com.adt.service.UserManager; @Le ^- v4
f2R+5`$
/** Q)%8NVs
* @author Joa Ul7pxzj
*/ f<s'prF
publicclass UserManagerImpl implements UserManager { l7D4`i<F
^t^<KL;
private UserDAO userDAO; NXWIE4T>*^
n8;G,[GM80
/** 'EH
* @param userDAO The userDAO to set. N#-kk3!Z;
*/ sa0^1$(<
publicvoid setUserDAO(UserDAO userDAO){ p)[BB6E
this.userDAO = userDAO; V5hlG =V
} $Kw"5cm
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/* (non-Javadoc) 63y':g
* @see com.adt.service.UserManager#listUser oRvm*"8B
3' :[i2[
(org.flyware.util.page.Page) ]~ g|SqPA@
*/ ^RFmRn
public Result listUser(Page page)throws D\_*,Fc
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HibernateException, ObjectNotFoundException { ru6H nLhL
int totalRecords = userDAO.getUserCount(); _uy5?auQ
if(totalRecords == 0) &:cTo(C'
throw new ObjectNotFoundException /O(;~1B
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k38
("userNotExist"); 9>$%F;JP44
page = PageUtil.createPage(page, totalRecords); ^B"_b?b
List users = userDAO.getUserByPage(page); ezq
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returnnew Result(page, users); ~i_R%z:y
} [(e`b
8L9S^ '
} s$nfY.C
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yn ?U7`V
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /wCxf5q0
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询,接下来编写UserDAO的代码: raI~BIfe
3. UserDAO 和 UserDAOImpl: <&m
java代码: r{:la56Xd
Om?:X!l"
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/*Created on 2005-7-15*/ =B{$U~}
package com.adt.dao; 7[?}kG
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import java.util.List; :-'ri Ry
2Z1(J% 7
import org.flyware.util.page.Page; Y8CYkJTAD-
O6/=/-?N=c
import net.sf.hibernate.HibernateException; XkfUPbU
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/** zm^p7&ak$
* @author Joa kU9AfAe
*/ U>M>FZ
publicinterface UserDAO extends BaseDAO { &)'kX
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publicList getUserByName(String name)throws P*^UU\x'4I
GMp'KEQQ
HibernateException; AxqTPx7`|
MS^hsUj}
publicint getUserCount()throws HibernateException; f*H}eu3/j
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publicList getUserByPage(Page page)throws P6Z,ci17
$/(/v?3][e
HibernateException; E6IL,Iq9
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} 21J82M
g=' 2~c
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T=KrT7
I3=Sc^zz&V
java代码: 9(Xch2tpO!
Z"8cGN'
eMMiSO!3
/*Created on 2005-7-15*/ sBG(CpQ
package com.adt.dao.impl; #[rFep
ON=ley
import java.util.List; KE1@z]
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import org.flyware.util.page.Page; K?<Odw'k
:z5Ibas:
import net.sf.hibernate.HibernateException; ,UJPLj^
import net.sf.hibernate.Query; O*"wQ50Ou
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import com.adt.dao.UserDAO; #z5?Y2t7~^
~x#-#nuh"
/** k5<