Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m8A#~i .
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;D3C>7y
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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 CyJEY-
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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 ni.cTOSx
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分页支持类: eWCb73
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java代码: joFm]3$;
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package com.javaeye.common.util; 1Ir21un
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import java.util.List; F^WP <0C
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publicclass PaginationSupport { Vx$ \hcG
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publicfinalstaticint PAGESIZE = 30; K18}W*$
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privateint pageSize = PAGESIZE; C6VLy x
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privateList items; "H7dft/
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privateint totalCount; {+] [5<q
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privateint[] indexes = newint[0]; o)h_H;
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privateint startIndex = 0; "i
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public PaginationSupport(List items, int {:Orn%Q
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totalCount){ Yrb{ByO&
setPageSize(PAGESIZE); C].iCxn
setTotalCount(totalCount); 3DzMB?I
setItems(items); )Q=_0;#;k
setStartIndex(0); >tYm+coS
} .8@$\ZRP
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public PaginationSupport(List items, int D[4u+g?[}>
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totalCount, int startIndex){ Bn^0^J-
setPageSize(PAGESIZE); TITKj?*o
setTotalCount(totalCount); L9r8BK;
setItems(items); J*r*X.
setStartIndex(startIndex); -f3p U:G8
} w{Ivmdto
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public PaginationSupport(List items, int \MA+f~)9
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totalCount, int pageSize, int startIndex){ C;;Sih5
setPageSize(pageSize); c?tBi9'Y]
setTotalCount(totalCount); q_Q/3rh
setItems(items); y0Fb_"}
setStartIndex(startIndex); 69PE9zz
} |N4.u
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publicList getItems(){
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return items; &b.=M>\9Q
} ?ME6+Z\
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publicvoid setItems(List items){ 35A|BD)q
this.items = items; ?8I?'\F;
}
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publicint getPageSize(){ R]vV*
return pageSize; KxI&G%z
}
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publicvoid setPageSize(int pageSize){ )fFb_U
this.pageSize = pageSize; :yL] ;J
} ed]=\Key
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publicint getTotalCount(){ ls_'')yp
return totalCount; "An,Q82oHf
} z#zI1Am(O
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publicvoid setTotalCount(int totalCount){ Qk0R a_
if(totalCount > 0){ V39g,=`b%
this.totalCount = totalCount; ?[VM6- &
int count = totalCount / -j+UMlkB
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pageSize; [^R^8k
if(totalCount % pageSize > 0) Gk.
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count++; |!1Y*|Q%s
indexes = newint[count]; (jnzT=y
for(int i = 0; i < count; i++){
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indexes = pageSize * ")_|69 VX
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} }'5MK
}else{ dWM'fg
this.totalCount = 0; *!4Z#Y
} szb_*)k
} i#&z2h-b
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publicint[] getIndexes(){ _mzW'~9wN
return indexes; aKV$pC<[o
} ; PF`Wj
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publicvoid setIndexes(int[] indexes){ +cD<:"L'g
this.indexes = indexes; Qn^'
} :<ka3<0%
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publicint getStartIndex(){ b1?#81
return startIndex; Kc!}`Pm
} }wWKFX
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publicvoid setStartIndex(int startIndex){ 8/DS:uM
if(totalCount <= 0) ucuSe!IcX
this.startIndex = 0; :lX!\(E2
elseif(startIndex >= totalCount) H;D>|q
this.startIndex = indexes heltgRt
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[indexes.length - 1]; Bt[/0>i
elseif(startIndex < 0) )}''L{k-
this.startIndex = 0; ?RX3MUN
else{ kJWn<5%ayg
this.startIndex = indexes K}2Erm%A@y
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[startIndex / pageSize]; qBU-~"2t
} hMzs*gK
} /Y*WBTV'
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publicint getNextIndex(){ 4]rnY~
int nextIndex = getStartIndex() + pny11C
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pageSize; #m lS}~n
if(nextIndex >= totalCount) x"eRJii?
return getStartIndex(); Xk:OL,c
else _G_Cj{w
return nextIndex; BoA/6FRi[
} R7]l{2V#^
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publicint getPreviousIndex(){ =31"fS@
int previousIndex = getStartIndex() - *zNYZ#
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pageSize; {qDSPo
if(previousIndex < 0) 9 ^o-EC!_
return0; MtM%{=&_
else y9_V
return previousIndex; O7u(}$D
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} ]~844Jp
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} h}-3\8 >
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抽象业务类 -_ I_W&
java代码: kM!kD4&
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/** %/EVUN9=
* Created on 2005-7-12 o-;E>N7t
*/ |HU@
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package com.javaeye.common.business; yZd +^QN
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import java.io.Serializable; R= a|Blp
import java.util.List; liEPCWl&
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import org.hibernate.Criteria; d[r#-h>dS
import org.hibernate.HibernateException; 3E7ULK
import org.hibernate.Session; D@C-5rmq
import org.hibernate.criterion.DetachedCriteria; X"MB|Ny
import org.hibernate.criterion.Projections; fz;iOjr>
import M]<?k]_p
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org.springframework.orm.hibernate3.HibernateCallback; ^*S ,xP
import M=.:,wRm
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org.springframework.orm.hibernate3.support.HibernateDaoS =nz}XH%=
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upport; g"Ljm7
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import com.javaeye.common.util.PaginationSupport; *?o{9v5}(
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public abstract class AbstractManager extends avjpA?Vz
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HibernateDaoSupport { @*>@AFnf\Z
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privateboolean cacheQueries = false; r$5i Wu
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privateString queryCacheRegion; lT4Hn;tnN
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publicvoid setCacheQueries(boolean |]QqXE-7
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cacheQueries){ W>!_|[a
this.cacheQueries = cacheQueries; 2#o>Z4 r{
} A2^\q>_#
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publicvoid setQueryCacheRegion(String cbeLu'DWB.
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queryCacheRegion){ yPM3a7-Bm
this.queryCacheRegion = ]FD'5p{
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queryCacheRegion; u?>B)PW
} R,)}>X|<
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publicvoid save(finalObject entity){ -r#X~2tPzD
getHibernateTemplate().save(entity); whonDG4WP
} rxr{/8%f%
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publicvoid persist(finalObject entity){ CQwL|$)]Y
getHibernateTemplate().save(entity); (E/lIou
} Fd?"-
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publicvoid update(finalObject entity){ ]"+95*B
getHibernateTemplate().update(entity); kR]!Vr*yh
} )=\#UE+W
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publicvoid delete(finalObject entity){ m1n.g4Z&*
getHibernateTemplate().delete(entity); W-Fu -Cz=
} ZPc@Zr`z
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publicObject load(finalClass entity, ";BlIovT=R
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finalSerializable id){ :*t"8;O[
return getHibernateTemplate().load =81@o,1w
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(entity, id); :
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} Ib|Rf;J~-
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publicObject get(finalClass entity, DKfE.p)
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finalSerializable id){ uqM yoIc
return getHibernateTemplate().get YWMGB#=
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(entity, id); <F'X<Bau
} RlheQTJ
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publicList findAll(finalClass entity){ J~B<7O<?!1
return getHibernateTemplate().find("from 7Q7-vx
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" + entity.getName()); 'D6T8B4
} ]V-W~r=
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publicList findByNamedQuery(finalString 76V
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namedQuery){ :gerQz4R8
return getHibernateTemplate kxp);
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().findByNamedQuery(namedQuery); YhbZ'SJ
} *\(r+>*x*
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publicList findByNamedQuery(finalString query, ZeUvyIG
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finalObject parameter){ 9Rn?
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return getHibernateTemplate {n/uh0>f*
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().findByNamedQuery(query, parameter); I/M _p^
} 4
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publicList findByNamedQuery(finalString query, 7@Zx@
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finalObject[] parameters){ ^
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return getHibernateTemplate @o#!EfZyE
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().findByNamedQuery(query, parameters); RletL)
} QYa(N[~a
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publicList find(finalString query){ wj[\B*$?
return getHibernateTemplate().find GiP`dtK
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(query); u$*56y
} fGw^:,B
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publicList find(finalString query, finalObject =`*O1a
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parameter){ 6el;Erp
return getHibernateTemplate().find +E1I");
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(query, parameter); Dq36p${\W
} >ELlnE8
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public PaginationSupport findPageByCriteria 6'kS_Zu{<
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(final DetachedCriteria detachedCriteria){ #
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return findPageByCriteria >H(i^z/c
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); D?C)BcN
} aO@7O*
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public PaginationSupport findPageByCriteria eh4gQ^l
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(final DetachedCriteria detachedCriteria, finalint Zm"{V iv]
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startIndex){ 5Xl/L
return findPageByCriteria 'fcMuBc+4
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(detachedCriteria, PaginationSupport.PAGESIZE, FP0G]=ME
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startIndex); {fha`i
} pl5P2&k
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public PaginationSupport findPageByCriteria f6_];]yP
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(final DetachedCriteria detachedCriteria, finalint |J+(:{}~
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pageSize, Sr&515
finalint startIndex){ ,g7.rEA
return(PaginationSupport) a-"k/P#
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getHibernateTemplate().execute(new HibernateCallback(){ q}/WQ]p} <
publicObject doInHibernate uKz,SqX
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(Session session)throws HibernateException { 2$14q$eb
Criteria criteria = zaFt*~@X
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detachedCriteria.getExecutableCriteria(session); 'WI^nZM
int totalCount = ybeKiv9
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((Integer) criteria.setProjection(Projections.rowCount \k]x;S<a
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()).uniqueResult()).intValue(); =/u%c!
criteria.setProjection pG34Qw
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(null); rQOWLg!"
List items = G
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criteria.setFirstResult(startIndex).setMaxResults xXY.AoO6
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d
(pageSize).list(); rwniOQe
PaginationSupport ps = DNR~_3Aq
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new PaginationSupport(items, totalCount, pageSize, U9&k;`
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startIndex); Tx1vL
return ps; ?E9D Xg
} c9\2YKo
}, true); anj#@U;!
} +vNZW@_$D
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public List findAllByCriteria(final ^A][)*SZ
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DetachedCriteria detachedCriteria){ 8>7RxSF
return(List) getHibernateTemplate b1gaj"]
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().execute(new HibernateCallback(){ G/d4f?RU
publicObject doInHibernate Q|,B*b
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(Session session)throws HibernateException { l
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Criteria criteria = #Ei,(xiP
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detachedCriteria.getExecutableCriteria(session); F$Ca;cP"
return criteria.list(); t ?h kL
} $s4Wkq
}, true); &m {kHM
} P_gYz!
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public int getCountByCriteria(final }C
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DetachedCriteria detachedCriteria){ 6AvHavA^Y
Integer count = (Integer) R#n%cXc|
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getHibernateTemplate().execute(new HibernateCallback(){ Y7GF$}%UL
publicObject doInHibernate hH->%*
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(Session session)throws HibernateException { ?
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Criteria criteria = ,;<RW]r-P
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detachedCriteria.getExecutableCriteria(session); ]WUC:6x
return T*I?9d{k
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criteria.setProjection(Projections.rowCount [EY`am8[
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()).uniqueResult(); <e)o1+[w
} a`E*\O'd
}, true); x|0:P sE
return count.intValue(); #5&jt@NS
} .fzu"XAPu
} kvGCbRC
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用户在web层构造查询条件detachedCriteria,和可选的 w?mEuXc
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 F_ 7H!F
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PaginationSupport的实例ps。 xMs]Hs
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ps.getItems()得到已分页好的结果集 WlV
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ps.getIndexes()得到分页索引的数组 9B dt (}0A
ps.getTotalCount()得到总结果数 E2AW7f(/
ps.getStartIndex()当前分页索引 Nt:8ogk/
ps.getNextIndex()下一页索引 kax\h
ps.getPreviousIndex()上一页索引 W3&tJ8*3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Y&*x4&Lb
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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 K?u(1
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一下代码重构了。 ?@R")$
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我把原本我的做法也提供出来供大家讨论吧: DlyMJ#a
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首先,为了实现分页查询,我封装了一个Page类: ?Qqd "=k4
java代码: K(T\9J.
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/*Created on 2005-4-14*/ n&-496H
package org.flyware.util.page; *~z#.63oZ
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/** 7ODaX.t->
* @author Joa -DO&