Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 % a.T@E
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 W ;+()vC
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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 XIZN9/;
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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 +_bxza(ma{
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分页支持类: @H~oOf
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java代码: Iu`S0#+
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package com.javaeye.common.util; v#<{Y'K
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import java.util.List; x{K"z4xbI
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publicclass PaginationSupport { *_#2|96)
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publicfinalstaticint PAGESIZE = 30; 6J}Yr5oD
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privateint pageSize = PAGESIZE; nHq4f&(H
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privateList items; KfZb=v;-l
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privateint totalCount; 2cIKph
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privateint[] indexes = newint[0]; !.t D.(XP
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privateint startIndex = 0; rKFnivGT
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public PaginationSupport(List items, int xDH#K0-#L
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totalCount){ JsuI&v
setPageSize(PAGESIZE); +Ss3Ph
setTotalCount(totalCount); zF>;7'\x
setItems(items); B]()
setStartIndex(0); #>,E"-]f
} |j9aTv[`
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public PaginationSupport(List items, int t0@AfO.'1
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totalCount, int startIndex){ 5p:BHw;%;
setPageSize(PAGESIZE); IpSWg
setTotalCount(totalCount); 4KR`
setItems(items); )1Y?S;
setStartIndex(startIndex); lz<'
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.
} Ev7v,7`z
w $-q&
public PaginationSupport(List items, int bolG3Tf|
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totalCount, int pageSize, int startIndex){ /J/V1dC}]D
setPageSize(pageSize); ]d7A|)q
setTotalCount(totalCount); |W=-/~X
setItems(items); -vT{D$&1
setStartIndex(startIndex); \-[bU6\A\
} ){'<67dK
/d:hW4}<}.
publicList getItems(){ Y_jc *S
return items; D|m3.si
} zaLPPm&f
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publicvoid setItems(List items){ D&o\q68W
this.items = items; srAWet
} ~TS!5Wiv
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publicint getPageSize(){ kV T |(Y
return pageSize; Sa[lYMuB
} (Sgsy^|N
tD}-&"REP
publicvoid setPageSize(int pageSize){ 0!ZaR6
this.pageSize = pageSize; `O0Qtq.
} c^pQitPv
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publicint getTotalCount(){ _,aFQ^]'9
return totalCount; P!IA;i
} QKts-b[3
4u%AZ<-C}m
publicvoid setTotalCount(int totalCount){ +75"Q:I
if(totalCount > 0){ .[1 f$
this.totalCount = totalCount; (GpP=lSSeY
int count = totalCount / 0#8, (6
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pageSize; 32SkxcfrCK
if(totalCount % pageSize > 0) =p=/@ FN
count++; :A @f[Y'9
indexes = newint[count]; )[ZXPD
for(int i = 0; i < count; i++){ S (xs;tZ
indexes = pageSize * 'Rsr*gX#
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} ~1}fL 1~5
}else{ j$/#2%OVN
this.totalCount = 0; $t}W,?
} (}>)X]
} <8kCmuGlk
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publicint[] getIndexes(){ >Ovz;
return indexes; 26k~Z}
} \$DBtq5=
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publicvoid setIndexes(int[] indexes){ WoGnJ0N q
this.indexes = indexes; 71P. 9Iz
} ![r)KE=v8I
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publicint getStartIndex(){ s[h;9
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return startIndex; ftPhE)i
} \ctzv``/n
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publicvoid setStartIndex(int startIndex){ Z]TQ+9t
if(totalCount <= 0) aZ\Z7(
this.startIndex = 0; Yu_
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elseif(startIndex >= totalCount) cl&?'`
)
this.startIndex = indexes ~uZ9%UB_m
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[indexes.length - 1]; MmvOyKNZF
elseif(startIndex < 0) $^^M&[b-
this.startIndex = 0; ',WJ'g
else{ c U(z5th
this.startIndex = indexes &K9RV4M5
@}!?}QU
[startIndex / pageSize]; {v=[~H>bt
} dnwzf=+>e
} I{U|'a
ts@$*
publicint getNextIndex(){ 8,RqhT)2#
int nextIndex = getStartIndex() + Q#ksf
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pageSize; N: 38N
if(nextIndex >= totalCount) o~9*J)X5i
return getStartIndex(); n[K%Xs)
else Q{uO/6
return nextIndex; -]u>kjiIT
} is^R8a
y&8`NS#_p?
publicint getPreviousIndex(){ -@#],s7
int previousIndex = getStartIndex() - xy!E_CuC$
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pageSize; ,Fkq/h
if(previousIndex < 0) #`%S[)RT
return0; A=|a!N/
else P(8
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return previousIndex; h@ ZC{B
} O_th/hl
*)^ZUk
} d$+0;D4E
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抽象业务类 XfMUodV-OZ
java代码: <'sm($.2
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/** 4[;}/-
* Created on 2005-7-12 b 1Wz
*/ P~:^bU^F7
package com.javaeye.common.business; T8&sPt,f
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import java.io.Serializable; Xg_l4!T_l
import java.util.List; iY2q^z/S
w?nSQBz$
import org.hibernate.Criteria; X_D-K F
import org.hibernate.HibernateException; zIS ,N '
import org.hibernate.Session; xnWezO_
import org.hibernate.criterion.DetachedCriteria; w^nA/=;r
import org.hibernate.criterion.Projections; `VGw5o
import Th\T$T`X$
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org.springframework.orm.hibernate3.HibernateCallback; g;AW
import tK *y/S
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org.springframework.orm.hibernate3.support.HibernateDaoS ]=xX_
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upport; A(`Mwh+
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import com.javaeye.common.util.PaginationSupport; ax;<idC}
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public abstract class AbstractManager extends T<Zi67QC@
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HibernateDaoSupport { DyZ6&*s$
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privateboolean cacheQueries = false; :cXN
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privateString queryCacheRegion; 7AGUi+!ICl
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publicvoid setCacheQueries(boolean ".#h$
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cacheQueries){ |<oqT+?i
this.cacheQueries = cacheQueries; x.|sCqx
} c0&!S-4M
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publicvoid setQueryCacheRegion(String z `\KQx
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queryCacheRegion){ t*Z5{
this.queryCacheRegion = FBouXu#
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queryCacheRegion; c`lL&*]
} N,VI55J:y>
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publicvoid save(finalObject entity){ xc`O\z_)
getHibernateTemplate().save(entity); pTTM(Hrx
} >nvK{6xR:
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publicvoid persist(finalObject entity){ ~Ij/vyB_
getHibernateTemplate().save(entity); J#3[,~
} MMD=4;X
M5_t#[ [
publicvoid update(finalObject entity){ i 2uSPV!Tf
getHibernateTemplate().update(entity); THK^u+~LM
} w&VDe(:~
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publicvoid delete(finalObject entity){ f;,*P,K
getHibernateTemplate().delete(entity); 0blbf@XA
} [fvjvN`
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publicObject load(finalClass entity, Q4]Od{[
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finalSerializable id){ akCCpnX_d
return getHibernateTemplate().load swJQwY
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(entity, id); o:4#AkS
} _E6N*ORV
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publicObject get(finalClass entity, U^)`_\/;?
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finalSerializable id){ }mUb1b
return getHibernateTemplate().get h>!9N
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(entity, id); mWn0"1C
} plJUQk
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publicList findAll(finalClass entity){ "}-S%v`)z
return getHibernateTemplate().find("from *ywr_9
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" + entity.getName()); ;/+U.I%z
} ,i;#e
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publicList findByNamedQuery(finalString ;$4&Qp:#
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namedQuery){ "*MF=VB1
return getHibernateTemplate N:+d=G`x
`YMd0*
().findByNamedQuery(namedQuery); SdnO#J}{
} >XM]UdP
:Y9/} b{
publicList findByNamedQuery(finalString query, IAe/)
qss)5a/x.
finalObject parameter){ $ye>;Ek
return getHibernateTemplate x_C0=Q|K3
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().findByNamedQuery(query, parameter);
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} tL<.B
w
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publicList findByNamedQuery(finalString query, ^7=7V0>,:
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finalObject[] parameters){ \.Op6ECV9
return getHibernateTemplate "{t]~urLd
asCcBp
().findByNamedQuery(query, parameters); yg~@}_C2_
} n;>=QG
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publicList find(finalString query){ 8B(v6(h
return getHibernateTemplate().find E'SDT*EI
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(query); %so{'rQl
} Qj(ppep\U"
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publicList find(finalString query, finalObject &,{YfAxQ`
{[L('MH2|
parameter){ 0!$y]Gr
return getHibernateTemplate().find 3 5L0CM
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(query, parameter); ]H\tz@
&
} uaU2D-ft"
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public PaginationSupport findPageByCriteria ,j.bdlI#
jcBZ#|B7;
(final DetachedCriteria detachedCriteria){ n5IQKYrg
return findPageByCriteria /m 7~-~$V
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 0\@oqw]6hv
} ijzwct#.
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public PaginationSupport findPageByCriteria "VU/Ucb7
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(final DetachedCriteria detachedCriteria, finalint
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pv-c>8Wb6
startIndex){ DL!%Np?`
return findPageByCriteria 2' ^7G@%
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(detachedCriteria, PaginationSupport.PAGESIZE, ={N1j<%fh
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startIndex); W}MN-0
} ?A*!rW:l;
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public PaginationSupport findPageByCriteria ,wBfGpVb
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(final DetachedCriteria detachedCriteria, finalint <1<xSr
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pageSize, oVPr`]
finalint startIndex){ 4neO$^i8J
return(PaginationSupport) Ek6g?rj_
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getHibernateTemplate().execute(new HibernateCallback(){ xk7Dx}
publicObject doInHibernate *kYGXT,f]
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(Session session)throws HibernateException { MtN!Xx
Criteria criteria = $60`Hh 4/
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detachedCriteria.getExecutableCriteria(session); gw[Eu>I
int totalCount = n^O!93a
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((Integer) criteria.setProjection(Projections.rowCount h8(>$A-
Pw thYy
()).uniqueResult()).intValue(); 0\B{~1(^
criteria.setProjection 0_MtmmL.
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(null); W g6H~x
List items = iemp%~UZ
$gD8[NAIx=
criteria.setFirstResult(startIndex).setMaxResults z0SF2L H
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(pageSize).list(); c:>&YGmhu
PaginationSupport ps = iR88L&U>
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new PaginationSupport(items, totalCount, pageSize, Qr4 D
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startIndex); 83gWA>Odh
return ps; 6o(IL-0]c
} NRp
}, true); hwJ>IQ1
} =y)K er
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public List findAllByCriteria(final 1;V_E2?V
@DY"~ccH
DetachedCriteria detachedCriteria){ nw%`CnzT
return(List) getHibernateTemplate yRXWd*9
gkA_<,38
().execute(new HibernateCallback(){ +{V`{'
publicObject doInHibernate >$E;."a
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(Session session)throws HibernateException { #RaqNu
Criteria criteria = |('o g *$
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detachedCriteria.getExecutableCriteria(session); jnTTj l
return criteria.list(); }zQgS8PQH
} 3,6f}:CG
}, true); ::$W
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} Y_!+Y<x7v
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public int getCountByCriteria(final qIsf!1I?
6L$KMYHE
DetachedCriteria detachedCriteria){ 4"(rZWv
Integer count = (Integer) Ddpcov
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getHibernateTemplate().execute(new HibernateCallback(){ -eyF9++`
publicObject doInHibernate dM= &?g
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(Session session)throws HibernateException { W0~G`A(:;
Criteria criteria = %<(d%&~
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detachedCriteria.getExecutableCriteria(session); 8B?U\cfa^
return ~~-VScG&
ftR& 5!Wm
criteria.setProjection(Projections.rowCount 83t/\x,Q
cGgfCF^`
()).uniqueResult(); c$7~EP
} gK({InOP
}, true); Z_m<x!
return count.intValue(); YI,t{Wy
} 62zu;p9m
} Q[rZ1z
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用户在web层构造查询条件detachedCriteria,和可选的 It&CM,=t
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Wtcib-
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PaginationSupport的实例ps。 3-{BXht)
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ps.getItems()得到已分页好的结果集 n{sk
ps.getIndexes()得到分页索引的数组 "YgpgW
ps.getTotalCount()得到总结果数 kodd7 AD
ps.getStartIndex()当前分页索引 nk%v|ZxoFv
ps.getNextIndex()下一页索引 52tc|j6~#
ps.getPreviousIndex()上一页索引 O=RS</01!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 iKJqMES
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 *0!p_Hco
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一下代码重构了。 9AX}V6\+
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我把原本我的做法也提供出来供大家讨论吧:
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首先,为了实现分页查询,我封装了一个Page类: /ta}12Z
java代码: A%W]XEa<
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/*Created on 2005-4-14*/ K%\r[NF
package org.flyware.util.page; W?.469yy
7UMZs7L$
/** 0HoHu*+FX
* @author Joa aM;SE9/U
* Y_:jc{?
*/ b3E1S+\=~
publicclass Page { .c+U=bV-
Y|fD)zG_
/** imply if the page has previous page */
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privateboolean hasPrePage; )0exGx+:
-|#{V.G3'
/** imply if the page has next page */ ZPG,o5`%
privateboolean hasNextPage; :.e'?a
7b>_vtrt
/** the number of every page */ #:gl+
privateint everyPage; U+x^!{[/
*O~y6|U?
/** the total page number */ )4=86>XJT
privateint totalPage; `z(o01y
Zpkd8@g@
/** the number of current page */ =6Ok4Z
privateint currentPage; Jq&Hz$L|
>^jBE''
/** the begin index of the records by the current T(?w}i
.T9$O]:o
query */ @Z
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privateint beginIndex; . fja;aG
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*gwlW/%Fz
/** The default constructor */ GLtWo+g0
public Page(){ :6nD "5(
\s*UUODWK
} I2$DlEke
metn&
/** construct the page by everyPage sWr;%<K
* @param everyPage 6v3l^~kc'
* */ 3O2G+G2
public Page(int everyPage){ ~ps,U
this.everyPage = everyPage; O]PM L`
} _gqqPny4$
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/** The whole constructor */ B8Fb$
public Page(boolean hasPrePage, boolean hasNextPage, "Wg,]$IvU
a
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int everyPage, int totalPage, OK80-/8HI
int currentPage, int beginIndex){ wPM>-F
this.hasPrePage = hasPrePage; ej-A=avd
this.hasNextPage = hasNextPage; 66pjWS
{X
this.everyPage = everyPage; Nj4CkMM[3
this.totalPage = totalPage; eTp|!T
this.currentPage = currentPage; H}kZ;8
this.beginIndex = beginIndex; i"a3POV>
} nm1dd{U6^
[L+*pW+$\.
/** k4V3.i!E
* @return ?-)!dl%N
* Returns the beginIndex. k 3m_L-
*/ [=(8yUV'G
publicint getBeginIndex(){ lZ-U/$od
return beginIndex; S3Y.+. 0U
} GmR3
a
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/** $,~Ily7w
* @param beginIndex ;-VZV p}Y
* The beginIndex to set. r"2lcNE
*/ +Xs E
publicvoid setBeginIndex(int beginIndex){ YYn8!FIe
this.beginIndex = beginIndex; &NBH'Rt
} BEaF-*?A
@??3d9I
/** ar<8wq<4G
* @return CK n2ZL
* Returns the currentPage. _dm0*T ?
*/ FB?~:7+'
publicint getCurrentPage(){ =Mx"+/Yo*
return currentPage; m*]`/:/X[
} i=#`7pt%'a
E\!X$
/** \~*<[.8~
* @param currentPage <{cY2cx~3
* The currentPage to set. 6
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*/ o`c+eMwr(
publicvoid setCurrentPage(int currentPage){ ~Tt@v`}
this.currentPage = currentPage; C^"zU>W_
} eY :"\c3
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/** j<~Wp$\i7>
* @return YjDQ`f/
* Returns the everyPage. gFp3=s0~
*/ {ze69 h
publicint getEveryPage(){ a5#G48'X
return everyPage; hP+4{F*}-
} |s!
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/** aPelt`
* @param everyPage gw"cXny
* The everyPage to set. Cy?]o?_?
*/ 1]:,Xa+|S
publicvoid setEveryPage(int everyPage){ {KHI(*r;
this.everyPage = everyPage; #1haq[Uv7
} /iO"4%v
o5s6$\"
/** vm|u~Yd,s
* @return +H3~Infr4f
* Returns the hasNextPage. `;}`>!8j
*/ A:(|"<lA
publicboolean getHasNextPage(){ Vbv^@Kp
return hasNextPage; 89:nF#
} cIw X sx
w317]-n
/** rQ*w3F?:
* @param hasNextPage iXm&\.%
* The hasNextPage to set. ~k&b
*/ (O J/u)W^
publicvoid setHasNextPage(boolean hasNextPage){ O6Py
this.hasNextPage = hasNextPage; 5&s6(?,Eu
} 9Do75S{(
$^fF}y6N
/** 1TQ?Fxj
* @return Xq$-&~
* Returns the hasPrePage. anW['!T9{s
*/ X&zGgP/
publicboolean getHasPrePage(){ ?sQg{1"Zr
return hasPrePage; nZB~l=
} Ij(<(y{?Q1
>`03EsU
/** P{)D_Bi
* @param hasPrePage g*b`o87PI
* The hasPrePage to set. -
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*/ (@}^ 3jpT
publicvoid setHasPrePage(boolean hasPrePage){ z~h?"'
this.hasPrePage = hasPrePage; =Oy& f:s
} ?Vg~7Eu0
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/** d=bKNA90
* @return Returns the totalPage. Oz%6y
ri
* ;t +p2i
*/ *}C%z(
publicint getTotalPage(){ @2"3RmYLo
return totalPage; 5Yv*f:
} D
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Nmx\qJUR(
/** `
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* @param totalPage (m2%7f.I
* The totalPage to set. 4|_xz;i
*/ :? B4q#]N
publicvoid setTotalPage(int totalPage){ *N$XQ{o
this.totalPage = totalPage; u;9iuc`*
} 6k0Awcr
nX:E(9q7c
} "}_J"%
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1L::Qu%E
:.AC%'S
3Y#
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 c<_1o!68
f.J^HQ_
个PageUtil,负责对Page对象进行构造: |I1,9ex
java代码: kKF=%J?X
O83J[YuzjN
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/*Created on 2005-4-14*/ k+{~#@
package org.flyware.util.page; -I{op
wd
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import org.apache.commons.logging.Log; #tZ!D^GQHq
import org.apache.commons.logging.LogFactory; 6%p6BK6
CL2zZk{u_
/** ]uFJ~:R
* @author Joa tiGH#~?
* pHR`%2!"t
*/ o%+w:u.
publicclass PageUtil { gtH^'vFZ
U $#^ e
privatestaticfinal Log logger = LogFactory.getLog 2#$7!`6K
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(PageUtil.class); x(u.(:V
-}TP)/!,*
/** t'Yd+FK
* Use the origin page to create a new page H$ nzyooh
* @param page f
] *w1
* @param totalRecords @{qcu\sZ
* @return H%n/;DW
*/ e;=R8i
publicstatic Page createPage(Page page, int l1zPL3"u_^
*H/)S 5
totalRecords){ sB:e:PK
return createPage(page.getEveryPage(), XC6 |<pru
-ioO8D&!
page.getCurrentPage(), totalRecords); gAvNm[=wD2
} P}AwE,&Q
JGq9RB]D$
/** )Mq4p'*A[
* the basic page utils not including exception
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X_-/j.
handler IrRy1][Qr
* @param everyPage "T /$K
* @param currentPage &O+S[~
* @param totalRecords |b@`ykD
* @return page tPiC?=4R
*/ #pRbRT9
publicstatic Page createPage(int everyPage, int ~Fvz&dO
3U?gw!M>
currentPage, int totalRecords){ W!el[@
everyPage = getEveryPage(everyPage); G:+D1J]
currentPage = getCurrentPage(currentPage); %}b
int beginIndex = getBeginIndex(everyPage, w@WtW8
p^
w`boQ_Ir
currentPage); Y_$!XIJ4
int totalPage = getTotalPage(everyPage, lz0dt<8eP
8B6(SQp%
totalRecords); $n8&5<
boolean hasNextPage = hasNextPage(currentPage, .vmCKZ
^&F.T-( A
totalPage); g[b;1$
boolean hasPrePage = hasPrePage(currentPage); pPs TgGai
`Q+O#l?
returnnew Page(hasPrePage, hasNextPage, hHMp=8J7
everyPage, totalPage, h{yh}04P1
currentPage, *@lVesC2
@?tR-L<u
beginIndex); (Z@-e^R
} 4%v-)HGh
P<1&kUZL
privatestaticint getEveryPage(int everyPage){ 4Vj]bm
return everyPage == 0 ? 10 : everyPage; A5fzyG
} Kk.\P|k2
'yOx&~H]
privatestaticint getCurrentPage(int currentPage){ #( 4)ps.
return currentPage == 0 ? 1 : currentPage; N["M "s(N
} J|V*g]#kP
:ldI1*@i<
privatestaticint getBeginIndex(int everyPage, int 3KD:JKn^
SPTx-b[
currentPage){ =`}|hI
return(currentPage - 1) * everyPage; <vg|8-,#m
} NSRY(#3
+;@R&Y
privatestaticint getTotalPage(int everyPage, int ak}ke
h _c11#
totalRecords){ j*VYUM@y1\
int totalPage = 0; IL&R&8'
=AK6^v&on
if(totalRecords % everyPage == 0) Ki:98a$
totalPage = totalRecords / everyPage; OpOR!
else 5=<fJXf5y
totalPage = totalRecords / everyPage + 1 ; Jk<b#SZ[b
v>hc\H1P
return totalPage; NCkrf]*F-
} jRk1Iu| 7
!9C]Fs*`?
privatestaticboolean hasPrePage(int currentPage){ B&3@b
return currentPage == 1 ? false : true; >4lA+1JYk
} ]C_$zbmi
M1DV 9~S
privatestaticboolean hasNextPage(int currentPage, 4GJx1O0Ol
^7kYG7/
int totalPage){ OJ\j6owA
return currentPage == totalPage || totalPage == a$11u.\q+
PVq y\i
0 ? false : true; pkIJbI{aS
} (:#4{C
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sBN4:8
} B`%%,SLJ
L@ N\8mf
NUY sQO)
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }N3Ur~X\
_rUsb4r
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 \$8p8MP<&D
"X1{*
做法如下: /h!iLun7I
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 v Dph}Z
#Nv0d|0\
的信息,和一个结果集List: G;msq=9|
java代码: !E/%Hv1
=-uk7uZM
7:)$oH
/*Created on 2005-6-13*/ {bp~_`O
package com.adt.bo; XR)I,@i`'
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import java.util.List; H? pWyc<,
N;av
import org.flyware.util.page.Page; _@]@&^K$E
:e4[isI
/** g5~1uU$O
* @author Joa ")qO#b4
*/ J$Ba*`~!!
publicclass Result { 4[LzjC
L_YY,
private Page page; 'q*/P&x5
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private List content; CY8=prC
HuL9' M
/** L5>.ku=T
* The default constructor 9y"\]G77E
*/ ,OO0*%
public Result(){ kasx4m]^
super(); _i&awm/U
} JMYM}G
cM+s)4TPL
/** CbRl/ 68HY
* The constructor using fields Zh.9j7
>p
* x42m+5/
* @param page .SSj=q4?
* @param content @y\M8C8
*/ J3=^+/g
public Result(Page page, List content){ \Mod4tQ
this.page = page; $zV[-d
this.content = content;
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} yu62$d
c_bIadE{
/** 0~N2MoOl^
* @return Returns the content. 5eSmyj-W
*/ 9G}Crp
publicList getContent(){ {-Y% wM8<i
return content; xyTjK.N
} ,n?oNU
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/** W 7Y5~%@
* @return Returns the page.
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*/ E MKv)5MH
public Page getPage(){ du4Q^-repC
return page; [L@ vC>G
} H23-%+*J
U.QjB0;
/** KC{HX?
* @param content
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* The content to set. =h2zIcj
*/ "S@%d(lg
public void setContent(List content){ ~nG?>
this.content = content; {__"Z<
} 6rOd80\
sjV>&eb
/** !j?2HlIK+
* @param page _/5mgn<GK
* The page to set. 8wqHr@}p
*/ sP5\R#
publicvoid setPage(Page page){ QGnBNsA h
this.page = page; q.>{d%?
} pTlNJ!U>
} Ey!+rq}
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\{[Gdj`
`8%2F}x}qD
;u0MY
2. 编写业务逻辑接口,并实现它(UserManager, $k|k 5cP8x
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UserManagerImpl) HW(cA}$
java代码: Q<V?rPAcx
*w538Vb
V'4sOn
/*Created on 2005-7-15*/ Q}M%
\v
package com.adt.service; r0)X]l7
ga~C?H,K
import net.sf.hibernate.HibernateException; "?GA}e"R
Em8C +EM
import org.flyware.util.page.Page; i`R}IP?71
7"`%-a$7
import com.adt.bo.Result; Jiljf2h
+Q3i&"QB.
/** W])<0R52
* @author Joa L}1|R*b
*/ >>voL DDd
publicinterface UserManager { /8i3 I5*
7 Ld5
public Result listUser(Page page)throws X
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%
j ,'$i[F'
HibernateException; 6WQT,@?
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} E}d@0C:
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r_f?H@ v
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3%G>TB
java代码: 0m^(|=N-
) )q4Rh
8(euWS
/*Created on 2005-7-15*/ c|%.B2
package com.adt.service.impl; s=&&gC1
Pvq74?an`
import java.util.List; 5
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B'OUT2cgB
import net.sf.hibernate.HibernateException; ruG5~dm>
i"~J -{d}
import org.flyware.util.page.Page; ao]Dm#HiO
import org.flyware.util.page.PageUtil; ua%$r[
SM2QF
import com.adt.bo.Result; P\B ]><!ep
import com.adt.dao.UserDAO; /d*0+m8
import com.adt.exception.ObjectNotFoundException; F/FUKXxx
import com.adt.service.UserManager; 0HA`
YQWGv,47\
/** )A}u)PH4O
* @author Joa dC$z q~q
*/ &>zzR$#1
publicclass UserManagerImpl implements UserManager { K]{Y >w
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private UserDAO userDAO; WleE$ ,
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/** ]3xb Q1
* @param userDAO The userDAO to set. (*>%^ C?
*/ x$o?ckyH
publicvoid setUserDAO(UserDAO userDAO){ 2 5DXJb^:
this.userDAO = userDAO; iYi3x_A`
} wJs#rkW
7{%_6b"
/* (non-Javadoc) );o2eV
* @see com.adt.service.UserManager#listUser ~)XyrKw
u]K&H&AxT
(org.flyware.util.page.Page) 4NaL#3
*/ 7JvBzD42
public Result listUser(Page page)throws %l4LX~-:
kcg{z8cd'r
HibernateException, ObjectNotFoundException { zO BLF|L=
int totalRecords = userDAO.getUserCount(); +ML4.$lc^
if(totalRecords == 0) +yvtd]D$2W
throw new ObjectNotFoundException + niz(]
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("userNotExist"); N?Byp&rqI<
page = PageUtil.createPage(page, totalRecords); 4PtRTb0<i3
List users = userDAO.getUserByPage(page); 0x&-/qce6W
returnnew Result(page, users); 5G!0Yy['
} >/@wht4- j
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} -][~_Hd{
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^O#>LbM"x
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v?Z30?_&h
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 F xek#
|$*1!pL-QP
询,接下来编写UserDAO的代码: d??;r:
3. UserDAO 和 UserDAOImpl: dwd5P7
java代码: <$6r1y*G
{kCCpU
a_jw4"Sb
/*Created on 2005-7-15*/ |\/`YRg>
package com.adt.dao; gEghDO_G
00jW s@K
import java.util.List; Q&j-a;L
z TYHwx
import org.flyware.util.page.Page; +ZFw3KEkz
#m
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import net.sf.hibernate.HibernateException; ='!E;
muh[wo
/** =<yMB d\
* @author Joa ~s3X&!#
*/ L|B/'
publicinterface UserDAO extends BaseDAO { Q=YIAGK
*0vq+C
publicList getUserByName(String name)throws O;zq(/,-l
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HibernateException; t zn1|
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publicint getUserCount()throws HibernateException; > 2)@(f~g
9:DT+^BB
publicList getUserByPage(Page page)throws 3K;V3pJ].
Db:^Omwo
HibernateException; kq| r6uE
S2y_5XJ<D
} tx` Z?K[
w)C/EHF
@c;XwU]2t
0m2%ucKw
m*bTELb
java代码: /thFs4
1SAO6Wh
C{{RU7iqc&
/*Created on 2005-7-15*/ 4S%s=vw
package com.adt.dao.impl; _3Kow{y\
Qy4eDv5
import java.util.List; eELLnU{"
d-X6yRjnj
import org.flyware.util.page.Page; 8dPDs#Zl
xG_LEk( zD
import net.sf.hibernate.HibernateException; [TX1\*W
import net.sf.hibernate.Query; mafnkQU
Z
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import com.adt.dao.UserDAO; a/wg%cWG_
CvOji1
/** >Hr&F
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* @author Joa ~ 3!yd0[k
*/
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public class UserDAOImpl extends BaseDAOHibernateImpl 1k)31GEQw
83(-/y
implements UserDAO {
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v(0IQ
/* (non-Javadoc) 'zJBp 9a%
* @see com.adt.dao.UserDAO#getUserByName :9H`O!VF
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(java.lang.String) i'cGB5-j
*/ ]EN+^i1F[
publicList getUserByName(String name)throws j.]ln}b/'+
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HibernateException { tDC?St1
String querySentence = "FROM user in class $~3?nib"j
m| uVmg!*
com.adt.po.User WHERE user.name=:name"; HfOaJ'+e<
Query query = getSession().createQuery YD9|2S!G
@vc9L
(querySentence); <lkt'iT=Sz
query.setParameter("name", name); po! [Nd&"
return query.list(); uVth&4dh9
} QbJE+m5
}j)][{i*x
/* (non-Javadoc) zQxTPd
* @see com.adt.dao.UserDAO#getUserCount() E8/Pi>QW
*/ BT^Im=A
publicint getUserCount()throws HibernateException { qdPmTaak
int count = 0; W-RqooEv
String querySentence = "SELECT count(*) FROM lRANXM
/Moyn"Kj{
user in class com.adt.po.User"; v) j3YhY
Query query = getSession().createQuery H'"=C&D~
>qy$W4
(querySentence); j'uzjs[
count = ((Integer)query.iterate().next qV#,]mX
cy64xR BB
()).intValue(); Qef5eih
return count; 6ys|'<?
} 6vfut$)[{
{1"kZL
/* (non-Javadoc) u0Bz]Ux/Q
* @see com.adt.dao.UserDAO#getUserByPage pzT,fmfk
K_Pbzj4(P
(org.flyware.util.page.Page) csFLBP
*/ %N#A1
publicList getUserByPage(Page page)throws 1f+z[ad&^
:IX_|8e ^
HibernateException { ^\oMsU5(
String querySentence = "FROM user in class &s8vmUt
D!DL6l`
com.adt.po.User"; P(bds
Query query = getSession().createQuery kmg/hNtN
\IhHbcF`d
(querySentence); ;uho.)%N`F
query.setFirstResult(page.getBeginIndex()) -]Ny-[P
.setMaxResults(page.getEveryPage()); yJ:rry
return query.list(); F Jp<J
} 7 \AoMk}
m;J'y2h =$
} yRivf.wH
ok1w4#%,
\;+TZ1i_
0}`0!Kv
WR9-HPF
至此,一个完整的分页程序完成。前台的只需要调用 }vb.>hy
P\y ZcL
userManager.listUser(page)即可得到一个Page对象和结果集对象 0Of6$`
C';Dc4j
的综合体,而传入的参数page对象则可以由前台传入,如果用 GP(nb,
65vsQ|Zw
webwork,甚至可以直接在配置文件中指定。 7*kTu0m
7sU+:a
下面给出一个webwork调用示例: N(kSE^skOa
java代码: ?X+PNw|pf
Y%!k'\n[2
{wl7&25
/*Created on 2005-6-17*/ -bgj<4R$p
package com.adt.action.user; G '%ZPh89
y5j ;Daq
import java.util.List; ~J0r%P
t~|`RMn"
import org.apache.commons.logging.Log; @dn&M9Z
import org.apache.commons.logging.LogFactory; BS2'BS8
import org.flyware.util.page.Page; 6"9(ce
KX
RNopx3
import com.adt.bo.Result; ;*{Ls#
import com.adt.service.UserService; NE><(02qW
import com.opensymphony.xwork.Action; ` Nv1sA#C
QBCEDv&j
/** kZ0z]Y
* @author Joa Ekn3ODz,
*/ ? r}2JHvN
publicclass ListUser implementsAction{ ( m7qc
l15Z8hYhj
privatestaticfinal Log logger = LogFactory.getLog 6H!l>@a7v
\D-X
_.v
(ListUser.class); @zJiR{Je-U
wn.UjxX.
private UserService userService; \"X_zM
@ %o'
private Page page; wkY$J\J
`NyO|9/4
privateList users; HOr Xxxp1^
n0)y|B#
/* R1Fcd@DWD
* (non-Javadoc) }((P)\s
* ~"Su2{"8B
* @see com.opensymphony.xwork.Action#execute() L/)eNZ
*/ ] I5&'#%2
publicString execute()throwsException{ z2jS(N?J1
Result result = userService.listUser(page); L=5Y^f'aU
page = result.getPage(); a{Y8hR
users = result.getContent(); hbSKlb0d
return SUCCESS; Of-8n-
} EgRuB@lw76
h(i_'P?
/** 8g?2( MT;
* @return Returns the page. Y}h&dAr
*/ F5+!Gb En
public Page getPage(){ a :CeI
return page; OX}ZdM!&f
} V"T5<HA9
w6ck wn,
/** \SBAk
h
* @return Returns the users. (rQ)0g@
*/ `j'gt&
publicList getUsers(){ id)J;!^;J
return users; keJ-ohv)
} ,nWZJ&B
of'H]IZ
/** U%K gLg#
* @param page [4-u{Tu
* The page to set. JmuoYl f|
*/ !
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publicvoid setPage(Page page){ L>rW S-
this.page = page; +D?Re%HI
} 6?-,@e
`a8 &7J(
/** ?SX0e(+}}
* @param users 1]aya(
* The users to set. ,w,)n^
*/ +$R%Vbd
publicvoid setUsers(List users){ 6-\C?w
A
this.users = users; N::.o+1
} 'EB5#
p]6/1&t