Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 8%UI<I,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?Afx{H7
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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 ?s<'3I{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 $Q[>v!!X
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分页支持类: {-sy,EYcw
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java代码: !cs+tm3
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package com.javaeye.common.util; ):.
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import java.util.List; p",HF%
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publicclass PaginationSupport { mW_<c,3D.
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publicfinalstaticint PAGESIZE = 30; x,\PV>
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privateint pageSize = PAGESIZE; Z=sC YLm
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privateList items; YQ`GOP#/
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privateint totalCount; $vS`w4Y
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privateint[] indexes = newint[0]; OT_w<te
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privateint startIndex = 0; tQy@d_a=y
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public PaginationSupport(List items, int Bv^{|w
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totalCount){ K8.=bGyg
setPageSize(PAGESIZE); V~+{douq
setTotalCount(totalCount); 6g*B=d(j
setItems(items); cH()Ze-B
setStartIndex(0); yfS`g-j{~
} jXO*_R
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public PaginationSupport(List items, int M"OXNPkc
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totalCount, int startIndex){ R{~Yh.)~
setPageSize(PAGESIZE); T!uK_
setTotalCount(totalCount); fiSc\C ~
setItems(items); cvpcadN[
setStartIndex(startIndex); E3#}:6m
} Y`QJcC(3
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public PaginationSupport(List items, int tVUoUl
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totalCount, int pageSize, int startIndex){ fbKL31PI
setPageSize(pageSize); FO{K=9O
setTotalCount(totalCount); Be{7Rj v
setItems(items); ,z1X{
setStartIndex(startIndex); @|xcrEnP}B
} qlJP2Ig~
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publicList getItems(){ C7`FM@z
return items; r%hnl9
} }d2]QD#O
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publicvoid setItems(List items){ T?W`g>yM
this.items = items; 3tMFJ ;*`
} @x">e][B
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publicint getPageSize(){ U}7a;4?
return pageSize; }O<u
} V.kUFTCvf
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publicvoid setPageSize(int pageSize){ x68$?CD
this.pageSize = pageSize; sm-RpZ&|
} "Y9
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publicint getTotalCount(){ 2H8,&lY.p
return totalCount; xX`P-h>V`c
} (eI'%1kS<
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publicvoid setTotalCount(int totalCount){ mh>)N"
if(totalCount > 0){ 5V\\w~&/
this.totalCount = totalCount; 2HBYReQ
int count = totalCount / UBp0;)-
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pageSize; %N@454enH
if(totalCount % pageSize > 0) 8V%(SV
count++; K
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indexes = newint[count]; F{\MIuoy
for(int i = 0; i < count; i++){ -.:[a3c?
indexes = pageSize * ;"=a-$vm
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i; +1Oi-$
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} ?<\K!dA
}else{ wn[q?|1
this.totalCount = 0; k/W$)b:Of`
} 6;U]l.
} 4f<%<Z
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publicint[] getIndexes(){ {w.rcObIw+
return indexes; iCCY222:
} +5Yc/Qp
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publicvoid setIndexes(int[] indexes){ PZ~uHX_d>
this.indexes = indexes; *Z=K9y,IC
} 4flyV -
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publicint getStartIndex(){ 3!^5a%u
return startIndex; RuDn1h#u{
} s8.O L_e
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publicvoid setStartIndex(int startIndex){ =jjUwcl
if(totalCount <= 0) nmp(%;<exN
this.startIndex = 0; Esw#D90q
elseif(startIndex >= totalCount) /j!?qID
this.startIndex = indexes QA\eXnR
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[indexes.length - 1]; k2l(!0o|;
elseif(startIndex < 0) L,0HX
this.startIndex = 0; hHF YAh
else{ g?!vRid@S
this.startIndex = indexes 4lH$BIAW
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[startIndex / pageSize]; uBw1Xud[YI
} RG-pN()
} $QmP'
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publicint getNextIndex(){ =1fO"|L
int nextIndex = getStartIndex() + g<O*4
]=
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pageSize; ,/{mRw%
if(nextIndex >= totalCount) a?K=
return getStartIndex(); sY!PXD0Q
else )Ac+5bs
return nextIndex; vr2tIKvpn
} D+d\<":
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publicint getPreviousIndex(){ h=umt<&D
int previousIndex = getStartIndex() - hN$6Kx>{
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pageSize; "40Jxqt
if(previousIndex < 0) .P.TqT@)r
return0; &bBK#d*-u?
else 7yxZe4~|#
return previousIndex; D`PnY&ffT
} JzMPLmgG/
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} LJDX6]4n
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抽象业务类 1iEZ9J?
java代码: !1K<iz_8
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/** $A,fO~
* Created on 2005-7-12 DbFTNoVR
*/ lG,/tMy
package com.javaeye.common.business; IZYq
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import java.io.Serializable; O{rgx~lLJt
import java.util.List; [R-4e; SRh
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import org.hibernate.Criteria; *IUw$|Z6z)
import org.hibernate.HibernateException; <_-&{Pv
import org.hibernate.Session; )vO;=%GQ
import org.hibernate.criterion.DetachedCriteria; +J30OT8
import org.hibernate.criterion.Projections; ZvEcExA-
import O=
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org.springframework.orm.hibernate3.HibernateCallback; 0{g @j{Lbz
import I^sWf3'db
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org.springframework.orm.hibernate3.support.HibernateDaoS "&%:
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upport; h[72iVn
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import com.javaeye.common.util.PaginationSupport; 6*%3O=*
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public abstract class AbstractManager extends WH2?_U-8h
xcr=AhqM
HibernateDaoSupport { q/~U[.C
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privateboolean cacheQueries = false; _S5\5[^
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privateString queryCacheRegion; awN{F6@ZE
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publicvoid setCacheQueries(boolean \^2%v~
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cacheQueries){ cMOvM0f
this.cacheQueries = cacheQueries; :#v8K;C
} &x19]?D"+
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publicvoid setQueryCacheRegion(String 5"xZ'M~=
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queryCacheRegion){ 4a]m=]Hm
this.queryCacheRegion = 4&;.>{:;
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queryCacheRegion; GCCmUR9d
} 8`}(N^=}
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publicvoid save(finalObject entity){ Cr|v3Y#h'
getHibernateTemplate().save(entity); jXq~ x"(
} xevG)m
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publicvoid persist(finalObject entity){ ),%/T,!@
getHibernateTemplate().save(entity); |E$Jt-'
} } r^@Xh
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publicvoid update(finalObject entity){ wOQ-sp0q0
getHibernateTemplate().update(entity); z)"7qqA
} dO.?S89L
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publicvoid delete(finalObject entity){ '(A)^K>+
getHibernateTemplate().delete(entity); &\8.y2=9p
} *m:h0[[J
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publicObject load(finalClass entity, -G&>b
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finalSerializable id){ q#wg2
return getHibernateTemplate().load ?T-6|vZA
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(entity, id); T5_z^7d
} qR0V\OtgY~
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publicObject get(finalClass entity, 3?I^D /K^
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finalSerializable id){ %J4]T35^2
return getHibernateTemplate().get U*F|Z4{W
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(entity, id); -\:#z4Tc
} 33x3zEUt6
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publicList findAll(finalClass entity){ Wh[+cH"M
return getHibernateTemplate().find("from H6?ZE
7cin?Z1
" + entity.getName()); b3}928!D-@
} j eF1{ %
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publicList findByNamedQuery(finalString cAJKFuX"
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namedQuery){ Vt{C80n&N
return getHibernateTemplate !
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().findByNamedQuery(namedQuery); Jhu<^pjs
} _l]`Og@Y
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publicList findByNamedQuery(finalString query, F4X/ )$Dk
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finalObject parameter){ l!e8=QlJ
return getHibernateTemplate l=*^FK]L`
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().findByNamedQuery(query, parameter); )3v0ex@Jl
} *0M#{HQ
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publicList findByNamedQuery(finalString query, *9e T#dH
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finalObject[] parameters){ 8=ubMqr[
return getHibernateTemplate !J!zi
pgz3d{]ua
().findByNamedQuery(query, parameters); I!lzOg4~
} SzkF-yRd
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publicList find(finalString query){ lM Gz"cym
return getHibernateTemplate().find J411bIxD+q
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(query); 3=~"<f
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} -H~g+i*J
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publicList find(finalString query, finalObject 7t`<`BY^
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parameter){ vFY/o,b \
return getHibernateTemplate().find pW O-YZ#+
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(query, parameter); f ^mxj/%L
} YXXUYi~!f
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public PaginationSupport findPageByCriteria 9x.vz
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(final DetachedCriteria detachedCriteria){ wqBGJ
return findPageByCriteria ie^:PcU
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); @eMDRbgq;[
} M x j
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public PaginationSupport findPageByCriteria !e6;@ *
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(final DetachedCriteria detachedCriteria, finalint Ou/@!Y1
8
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startIndex){ 6HpSZa
return findPageByCriteria I^/Ugu
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(detachedCriteria, PaginationSupport.PAGESIZE, ;5#P?
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startIndex); =wK3\rG
} R0+v5E
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public PaginationSupport findPageByCriteria w( `X P
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(final DetachedCriteria detachedCriteria, finalint >4 GhI65
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pageSize, N'Va&"&73>
finalint startIndex){ ,^O**k9F
return(PaginationSupport) `m<l8'g
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getHibernateTemplate().execute(new HibernateCallback(){ ]g3&gw
publicObject doInHibernate {>OuxVl??k
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(Session session)throws HibernateException { i\2MphS
Criteria criteria = U6FM`w<
l3n* b6
detachedCriteria.getExecutableCriteria(session); l0Jpf9Aue
int totalCount = lW'6rat
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((Integer) criteria.setProjection(Projections.rowCount wM (!9Ws3
^mFuZ~g;?
()).uniqueResult()).intValue(); NAV}q<@v
criteria.setProjection Svn|vH
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(null); a}#[mw@m=
List items = Eag->mw/~
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)
criteria.setFirstResult(startIndex).setMaxResults ~b5aT;ObR
O<S*bN>BF
(pageSize).list(); !6|Kpy8
PaginationSupport ps = L':;Vv~-
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new PaginationSupport(items, totalCount, pageSize, 4PTHUyX
ItQI M#
startIndex); En+4@BC
return ps; +Es3iE @
} aMuc]Wy#
}, true); )!3XM
} Cst\_j
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public List findAllByCriteria(final =Xm
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DetachedCriteria detachedCriteria){ 8U\;N
return(List) getHibernateTemplate 9%oLv25{)
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().execute(new HibernateCallback(){ r$;DA<<|<c
publicObject doInHibernate .qy._C2(
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(Session session)throws HibernateException { =r+u!~%@''
Criteria criteria = g63:WX-\
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detachedCriteria.getExecutableCriteria(session); C5i]n? )S
return criteria.list(); 9+@_ZI-
} //Ioh (N
}, true); (Z)
} k<"ZNQm$.
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public int getCountByCriteria(final ?ZdHuuDN~
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DetachedCriteria detachedCriteria){ "My \&0-
Integer count = (Integer) KmZUDU%R
[[JwHM8H&
getHibernateTemplate().execute(new HibernateCallback(){ ^qiTO`lg
publicObject doInHibernate !rb)Y;WQt
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(Session session)throws HibernateException { (o{QSk\
Criteria criteria = vb9G_Pfz
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detachedCriteria.getExecutableCriteria(session); ; z :}OD
return :Ff1Js(Z
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criteria.setProjection(Projections.rowCount / !jd%,G
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()).uniqueResult(); V5K`TC^
} ?OYu BZF
}, true); PAH;
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return count.intValue(); Niou=PI@
} (8@._
} SWO$#X /
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用户在web层构造查询条件detachedCriteria,和可选的 n0O- Bxhl
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ED[PP2[/
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PaginationSupport的实例ps。 -78
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ps.getItems()得到已分页好的结果集 _R]la&^2F\
ps.getIndexes()得到分页索引的数组 rxIfatp^
ps.getTotalCount()得到总结果数 *7nlel
ps.getStartIndex()当前分页索引 3tS~/o+]
ps.getNextIndex()下一页索引 mcb0%
ps.getPreviousIndex()上一页索引 #]:yCiA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 -2K`:}\y&
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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 8D)*~C'85E
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一下代码重构了。 $?(fiFC
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我把原本我的做法也提供出来供大家讨论吧: Ts|&_|
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首先,为了实现分页查询,我封装了一个Page类: H;G*tje/M
java代码: K)sO
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/*Created on 2005-4-14*/ %z`bu2
package org.flyware.util.page; )<1M'2
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/** lk%rE
* @author Joa 3vHEPm]
* IM}#k$vM:
*/ J ;i/X;^
publicclass Page { `+\+
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/** imply if the page has previous page */ 9-Qub+0o
privateboolean hasPrePage; IpB0~`7YI
x>!#8?-h
/** imply if the page has next page */ ts{Tk5+
privateboolean hasNextPage; tlCgW)<?
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/** the number of every page */ y_Bmd
privateint everyPage; g(,gg1mG
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/** the total page number */ nr!kx)j
privateint totalPage; G3OqRH
7 H.2]X
/** the number of current page */ 0{@E=}}h
privateint currentPage; Hp8)-eT
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/** the begin index of the records by the current Z[FSy-;"
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query */ s0E:hn:
privateint beginIndex; &xj?MgdNL
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/** The default constructor */ Z8 1]>
public Page(){ 4@4$kro
%_(e{Mf)
} k,0JW=Vh>|
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/** construct the page by everyPage Ih{(d O;
* @param everyPage |*fGG?}
* */ V'mQ{[{R
public Page(int everyPage){ C^2Tql
this.everyPage = everyPage; \.POb5]p0
} /U`"Xx
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/** The whole constructor */ {Ymn_
public Page(boolean hasPrePage, boolean hasNextPage, 2Vr F~+
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int everyPage, int totalPage, 0AZ Vc
int currentPage, int beginIndex){ ido'<;4>
this.hasPrePage = hasPrePage; ?N~rms
e
this.hasNextPage = hasNextPage; ~Ub'5M
this.everyPage = everyPage; ~N;kF.q&>&
this.totalPage = totalPage; y['$^T?oP
this.currentPage = currentPage; {uM*.]
this.beginIndex = beginIndex; jri=UGf
} gH,^XZe
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/** kbN2dL
* @return ,@;",
* Returns the beginIndex. x<>#G~-
*/ ] L"jt8E
publicint getBeginIndex(){ Xat>d>nJ]
return beginIndex; yS0!#AG
} X"z^4?Aj+
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/** MD1n+FgTu
* @param beginIndex L09YA
* The beginIndex to set. ||;V5iR:
*/ 0>6J -
publicvoid setBeginIndex(int beginIndex){ @a'Rn
this.beginIndex = beginIndex; P6!c-\
} [o<Rgq4
dzjp,c@
/** \'xF\V
* @return /vYuwaWG=
* Returns the currentPage. l:-$ulAx
*/ 3,8<5)ds*
publicint getCurrentPage(){ Bk_23ygO_
return currentPage; j_H9l,V
} )>QpR8
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/** <'>c`80@\*
* @param currentPage v,I4ozDx
* The currentPage to set. ve49m%NQ
*/ bJ4} )P&
publicvoid setCurrentPage(int currentPage){ *P7 H=Yf&
this.currentPage = currentPage; h64<F3}
} !i,Eo-[Z
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/** 93Kd7x-3
* @return ><V<}&:y$(
* Returns the everyPage. $M5iU@A
*/ M+j V`J!
publicint getEveryPage(){ (u-K^xC
return everyPage; w[YiH $
}
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/** vMu6u .e
* @param everyPage >x9@if
* The everyPage to set. lD)ZMaaS3
*/ Hb55RilC
publicvoid setEveryPage(int everyPage){ D_]4]&QYT
this.everyPage = everyPage; S~()A*5
} wXZ"}uT<}
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/** "m,)3zND3
* @return Y)H~*-vGu
* Returns the hasNextPage. H(Pzo+k*
*/
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publicboolean getHasNextPage(){ aO)Cq5
return hasNextPage; @`xR1pXQ
} 6|:K1bI)
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/** `v?XFwnV`
* @param hasNextPage UR?biq
* The hasNextPage to set. ;l`us
*/ L|ZxB7xk
publicvoid setHasNextPage(boolean hasNextPage){ ]dIcW9a
this.hasNextPage = hasNextPage; bca4'`3\|
} $$F iCMI
S9RH&/^H
/** yhm6%
* @return znnnqR0us
* Returns the hasPrePage. 0h/bC)z
*/ =\~<##sRJ
publicboolean getHasPrePage(){ u#!QIQW
return hasPrePage; tf[)Q:|
} a;bmZh
ZDny=&>#
/** K93L-K^J
* @param hasPrePage %4' <0
* The hasPrePage to set. 0RFBun{
*/ $-Iui0h
publicvoid setHasPrePage(boolean hasPrePage){ D8X~qt/
this.hasPrePage = hasPrePage; ^G(U@-0..
} =d`w~iC
MTXh-9DA
/** jKr\mb
* @return Returns the totalPage. P^[eTR*?
* pLj[b4p9
*/ o-I:p$B -
publicint getTotalPage(){ >|zMN$:
return totalPage; +xNV1bM
} O]_a$U*6
#1fL2nlP*E
/** N_wj,yF*
* @param totalPage 8=!uQQ
* The totalPage to set. <qGxkV
*/ Op()`x
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publicvoid setTotalPage(int totalPage){ g'cLc5\
this.totalPage = totalPage; %\"<lyD
} Ua hsX
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} mqj]=Fq*
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6}l[%8
s!<RWy+
z@I'Ryalyc
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 tNoPpIu
CiWz>HWH
个PageUtil,负责对Page对象进行构造: S^s|/!>
java代码: \uPyvA=
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/*Created on 2005-4-14*/ uwl_TDc>%
package org.flyware.util.page; JAx0(MZO
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import org.apache.commons.logging.Log; Ty<."dyPW
import org.apache.commons.logging.LogFactory; m^%@bu,
bog3=Ig-
/** f+!k:}K
* @author Joa `%A vn<
* mF:Pplf<
*/ 5o6X.sC8e
publicclass PageUtil { mqtX7rej
]f{3_M[
privatestaticfinal Log logger = LogFactory.getLog HmiG%1+{A
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(PageUtil.class); Upa F>,kM
QUeuN?3X\
/** .af+h<RG4$
* Use the origin page to create a new page ZyM7)!+kPa
* @param page %rlMjF'tG
* @param totalRecords (/7b8)g
* @return hCBre5
*/ &%]v0QK
publicstatic Page createPage(Page page, int v-Tkp
Yn
j(A>M_f;
totalRecords){ 3{)!T;W d
return createPage(page.getEveryPage(), ?;VsA>PV
+=:_a$98
page.getCurrentPage(), totalRecords); `>0%Ha
} 577#A, O
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/** cO$xT;kK
* the basic page utils not including exception |k$6"dXSO
P!Brw72
handler Q5c3C&$6
* @param everyPage /!?b&N/d)
* @param currentPage EHy 15RL
* @param totalRecords D V\7KKJE
* @return page Mz6\T'rC
*/ X1HEeJ|
publicstatic Page createPage(int everyPage, int }.a{;{y
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currentPage, int totalRecords){ >AFQm
everyPage = getEveryPage(everyPage); <Drm#2x!E
currentPage = getCurrentPage(currentPage); yg.o?eML
int beginIndex = getBeginIndex(everyPage, ~&?57Sw*m
X J`*dgJ
currentPage); Xdi<V_!BC-
int totalPage = getTotalPage(everyPage, qV9}N-sS
$PG(>1e
totalRecords); Qs '_\|/-
boolean hasNextPage = hasNextPage(currentPage, 3!
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totalPage); |a#=o}R_
boolean hasPrePage = hasPrePage(currentPage); P3 .
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returnnew Page(hasPrePage, hasNextPage, ClY`2
everyPage, totalPage, Iprt
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currentPage, T+^Sa
J
ic5af"/(\
beginIndex); uh2 Fr
} uH?dy55Y
idB1%?<
privatestaticint getEveryPage(int everyPage){ eL>wKu:r
return everyPage == 0 ? 10 : everyPage; p5jR;nOZ%l
} !E&l=*lM.
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privatestaticint getCurrentPage(int currentPage){ vf zC2
return currentPage == 0 ? 1 : currentPage; 0cSm^a
} vh.-9eD
Zb=;\l*&
privatestaticint getBeginIndex(int everyPage, int MJh.)kd$
ep~+]7\
currentPage){ ber&!9
return(currentPage - 1) * everyPage; L[ZS17;*
} +m]-)
'<3h8\"
privatestaticint getTotalPage(int everyPage, int ,ss"s3
c(uDkX
totalRecords){ wK0x\V6dJ
int totalPage = 0; (kVY\!UAt
]isq}Qv~
if(totalRecords % everyPage == 0) >|, <9z`D
totalPage = totalRecords / everyPage; ~;jgl_5?b
else <jh7G
totalPage = totalRecords / everyPage + 1 ; 0Ix,c( %
)u+O~Y95&i
return totalPage; k,$/l1D
} 'j*Q
qH0JZdk
privatestaticboolean hasPrePage(int currentPage){ %X's/;(Lx`
return currentPage == 1 ? false : true; sBYDo{01
} JN:L%If
^\g.iuE
privatestaticboolean hasNextPage(int currentPage, H#7=s{u
*Lxt{z`9
int totalPage){ c0Bqm
return currentPage == totalPage || totalPage == wm^1Fn--
}-sh
0 ? false : true; SOE-Kio=B
} =xDxX#3
%19~9Tw
pdm(7^
} Zo-,TKgY'
@sG*u >
t{yj`Vg
0ETT@/)]z
'.<iV!ZdZ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 x]yIe&*('
* #E_KW1RV
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 [Rub
4i.&geXA.
做法如下: @54$IhhT~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 b+q'xnA=>
0<:rp]<,
的信息,和一个结果集List: P5h*RV>oS
java代码: ?mM:oQH+>
X3 1%T"
R<gAxO%8
/*Created on 2005-6-13*/ hSxK*.W*3
package com.adt.bo; Iila|,cM
GApvRR+Z
import java.util.List; pY-!NoES
~Er0$+q=Y;
import org.flyware.util.page.Page; [T4{K&
JBA{i45x
/** xv Xci W
* @author Joa 8\9W:D@"x
*/ b:'8_jL
publicclass Result { (1q(6!
ftcLP
private Page page; q+4dHS)x
5x|$q kI
private List content; AA)pV-
X.>~DT%0Lm
/** D~W1["[
* The default constructor Id3i qAL
*/ Op^r }7
public Result(){ $OK}jSH*v)
super(); 1Ao YG_
} ,TY&N-
B.nq3;Y
/** [UN`~
* The constructor using fields 1PLxc)LsG
* <
&[=,R0 @
* @param page FZTBvdUYp
* @param content *I7$\0Q
*/ dx{ZG'@aH
public Result(Page page, List content){ HY[eo/nM1d
this.page = page; {U?UM
this.content = content; 1DPgiIG~
} $y~!ePKh
i,jPULzyjk
/** B\BxF6 y
* @return Returns the content. kWs"v6B
*/ ;2X/)sxWz
publicList getContent(){ h^#K4/
return content; 5(kRFb'31F
} ajFSbi)l
!e*BQ3
/** ^s<p5V
* @return Returns the page. ,gHgb
*/ Tdvw7I-q
public Page getPage(){ `[vm{+i
return page; g:bw;6^u
} ^M60#gJ
u\gPx4]4c
/** _bp9UJ
* @param content dQ+{Dv3A
* The content to set. Wt2+D{@8
*/ ]DcQ8D
public void setContent(List content){ |/B2Bm
this.content = content; i}mvKV?!|1
} (~t/8!7N
^|KX)g
/** Y'6GY*dL
* @param page /8 /2#`3R
* The page to set. \yeo-uN8
*/ 1RC(T{\x
publicvoid setPage(Page page){ u'"VbW3u n
this.page = page; >W%tEc
} #SiOx/
} B=K&+
FbRq h|
j_2-
xf/
SUO
F
*3_@#Uu7
2. 编写业务逻辑接口,并实现它(UserManager, +/ ,J$(
qF!oP
UserManagerImpl) kqJ\kd
java代码: 9(`d
h
kI5`[\
&_cMbFLBP
/*Created on 2005-7-15*/ (9bFIvMc
package com.adt.service; Y>}[c
*,Bo $:(n
import net.sf.hibernate.HibernateException; /$v0Rq9
Ik_u34U
import org.flyware.util.page.Page; 8RC7Ei
y#-mj,e
import com.adt.bo.Result; OmO/x
9Yg=4>#$
/** I8=p_Ie
* @author Joa Si[:l
*/ E;7vGGf]
publicinterface UserManager { ]mEY/)~7
MpZ
#
public Result listUser(Page page)throws Ra%" +=
l*;Isz:
HibernateException; V@6,\1#`|
P9j[
NEV
} 8.9TWsZ
,U9gg-.Lp
0Q]@T@F.
eq)8V x0
md8r"
java代码: %hcn|-"F
oZ%rzLH
KtWn08D!
/*Created on 2005-7-15*/ 5(F @KeH>
package com.adt.service.impl; Dk$[b9b
:_R[@?c
import java.util.List; X.)caF^j
x|
jBn}
import net.sf.hibernate.HibernateException; RL=
{%WQQs
import org.flyware.util.page.Page; y8/
7@qw
import org.flyware.util.page.PageUtil; s&-m!|P
tz0_S7h
import com.adt.bo.Result; q.]>uBAQ?
import com.adt.dao.UserDAO; xE+Nz5F
import com.adt.exception.ObjectNotFoundException; 1t"
import com.adt.service.UserManager; <[9{Lg*D
o' U::
/** M~ =Bln5
* @author Joa pa1.+ ~)
*/ ZMs$C3
publicclass UserManagerImpl implements UserManager { +k=BD s
W-9?|ei
private UserDAO userDAO; !KiN} p
iC]=S}
/** FGzMbi<l#(
* @param userDAO The userDAO to set. +S!gS|8P
*/ >_9w4g_<
publicvoid setUserDAO(UserDAO userDAO){ [UqJ3@>
this.userDAO = userDAO; L`v7|! X
} *aKT&5Ch-
US<bM@[
/* (non-Javadoc) p
BU,"Yy&
* @see com.adt.service.UserManager#listUser b(<#n6a}\
q}vz]L&o
(org.flyware.util.page.Page) *Mu X]JK
*/ :q6j{C(
public Result listUser(Page page)throws kjWY{7b!
~&bn}
M>W
HibernateException, ObjectNotFoundException { e!_+TyI
int totalRecords = userDAO.getUserCount(); 0 t. '?=
if(totalRecords == 0) 5#Z> }@/
throw new ObjectNotFoundException )TNAgTmqK
KW^#DI6tr
("userNotExist"); F'eV%g
page = PageUtil.createPage(page, totalRecords); ;0j 8Xj
List users = userDAO.getUserByPage(page); v6r,2Va/
returnnew Result(page, users); _M.7%k/U8
} !L..I2'
)2
E7>SQc~
} ruMS5OqM
3@'3U?Hin
}u"iA^'Ot
<[7
bUB
(of=hzT^?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rGPFPsMQ]
C'4gve 7!
询,接下来编写UserDAO的代码: 83rtQ;L
3. UserDAO 和 UserDAOImpl: "P4#Q_
java代码: \UKr|[P
Jzqv6A3G
*AEN
/*Created on 2005-7-15*/ &p/^A[
package com.adt.dao; @m*^v\q<u
J!l/!Z>!cF
import java.util.List; }=)
zCOzBL/1q
import org.flyware.util.page.Page; g\%vkK&I
D]NfA2B7
import net.sf.hibernate.HibernateException; eUa2"=M
Yv="oG!xL
/** d9'gH#f?
* @author Joa &YAw~1A
*/ P2lDi!q|
publicinterface UserDAO extends BaseDAO { ~0S_S +e
sj@B0R=Qo
publicList getUserByName(String name)throws ^zdZ"\x
Z_Tu*
F
HibernateException; gQXB=ywF
#=>t6B4af
publicint getUserCount()throws HibernateException; XYeuYLut
PjL"7^Q&
publicList getUserByPage(Page page)throws @qC](5|TQ
;xp^FKP
HibernateException; +mc0:e{WF
1trk
} 4g^nhJP$
$@H]0<3,
Qw&It
?Q`u\G3.m
IF"-{@
java代码: (]*otVJ
?`jh5Kw%y
Xbm\"g \
/*Created on 2005-7-15*/ s@Q,
wa(
package com.adt.dao.impl; _FG?zE
^Q)&lxlxpx
import java.util.List; ryk(Am<
.i^aYbB$X
import org.flyware.util.page.Page; 6xLLIby,
'"#W!p
import net.sf.hibernate.HibernateException; zUw=e}?:
import net.sf.hibernate.Query; e
MX?x7
"oZ$/ap\
import com.adt.dao.UserDAO; /wF*@ /PTH
)U>JFgpIW
/** Ucj
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* @author Joa l]pHj4`uv
*/ _z`g@[m:t
public class UserDAOImpl extends BaseDAOHibernateImpl JIw=Bs
,U-aZ
implements UserDAO { Q/JX8<7K
-UJ; =/
/* (non-Javadoc) q6xm#Fd'.
* @see com.adt.dao.UserDAO#getUserByName 3_AVJv
;N
d&z^u.SY
(java.lang.String) xy/B<.M1
*/ p>GTFXEi6
publicList getUserByName(String name)throws zjuU*$A4
Tc{n]TV
HibernateException { "JHdF&
String querySentence = "FROM user in class rD7L==Ld
]z^*1^u^ig
com.adt.po.User WHERE user.name=:name"; {w,g~ew
`
Query query = getSession().createQuery D7|=ev
@qszwQav$
(querySentence); U64WTS@
query.setParameter("name", name); hcQky/c\#b
return query.list(); ,5tW|=0@
} m^6& !`CD
-Fl;;jeX
/* (non-Javadoc) ?b}d"QsmU
* @see com.adt.dao.UserDAO#getUserCount() zcn> 4E)
*/ =TTk5(m
publicint getUserCount()throws HibernateException { 7RH1,k
int count = 0; "`QI2{!l
String querySentence = "SELECT count(*) FROM 9_~[
Xup"gYTZQ
user in class com.adt.po.User"; "r:i
Query query = getSession().createQuery D^R=
G-54D_ 4
(querySentence); f{m,?[1C,
count = ((Integer)query.iterate().next YPq4VX,
A7|CG[wZ
()).intValue(); V l,V
return count; i4',d#
} {C% #r@6
>EMsBX
/* (non-Javadoc) .V4w+:i
* @see com.adt.dao.UserDAO#getUserByPage XN*?<s3
9:JFG{M
(org.flyware.util.page.Page) v,=[!=8!
*/ Sr9)i8x{
publicList getUserByPage(Page page)throws (JgW")M`cY
X {["4
HibernateException { (wMiXi
String querySentence = "FROM user in class F|rJ{=x
;q8tOvQ
com.adt.po.User"; R{GT?
wl
Query query = getSession().createQuery f3g#(1
_kgGz@/p
(querySentence); P|:*OM
p
query.setFirstResult(page.getBeginIndex()) sHt
PO[h
.setMaxResults(page.getEveryPage());
;8?i
return query.list(); ~v
/N G
} qIO<\Yl
s,tZi6Z=%E
} ] bPj%sb*@
1XwW4cZ>:
]VYv>o`2
`|t X[':
6:(R/9!P
至此,一个完整的分页程序完成。前台的只需要调用 efK3{
H
3e(-
userManager.listUser(page)即可得到一个Page对象和结果集对象 T)!$-qdz/
$?Et sf#*'
的综合体,而传入的参数page对象则可以由前台传入,如果用 YY&3M
3@d{C^\
webwork,甚至可以直接在配置文件中指定。 !I7bxDzK$
,wI$O8"!j
下面给出一个webwork调用示例: Usa
java代码: eHjna\ C
't3@dz_dG
W7j-siWJ
/*Created on 2005-6-17*/ -T
s8y
package com.adt.action.user; &~%(
RO
n@hf{hA[a
import java.util.List; iva?3.t
rO_|_nV[
import org.apache.commons.logging.Log; VcLB0T7m\
import org.apache.commons.logging.LogFactory; shjq4#9
import org.flyware.util.page.Page; fn!(cE|`E
Mp8FYPjZ
import com.adt.bo.Result; #6jdv|fu
import com.adt.service.UserService; r_5k$u(
import com.opensymphony.xwork.Action; yNVmTb9mF
&_DRrp0CN
/** ?r`UBR+[
* @author Joa TAkM-iyH]
*/ sRM3G]nUr
publicclass ListUser implementsAction{ ?|&plf|
Eyv|~D
privatestaticfinal Log logger = LogFactory.getLog &TpzJcd"
A3\%t@y
(ListUser.class); =:|fN3nJ2
!hBzT7CO
private UserService userService; d%"?^e
:;wb{q$O
private Page page; !uC`7a
}G:5P3f
privateList users; +cDz`)N,,
^kS44pr\Q
/* FUq>+U!Qu
* (non-Javadoc) uV\ _j3,2
* d1MVhE
* @see com.opensymphony.xwork.Action#execute() 6X@]<R
*/ R^fk :3
publicString execute()throwsException{ AADvk_R
Result result = userService.listUser(page); [lSQ?
page = result.getPage(); Uf:G,%OYi
users = result.getContent(); V4('}Q!
return SUCCESS; 5M.KF;P
} 97$1na3gq
#WOb&h
/** a^9-9*
* @return Returns the page. aCL_cVOMR
*/ W?(^|<W
public Page getPage(){ mXX9Aa>
return page; 6l{=[\.Xa
} .szs?
N|pyp*8Z
/** X j'7nj
* @return Returns the users. rCwjy&SuU^
*/ v7"Hvp3w
publicList getUsers(){ 64#6L.Q-c
return users; d/Sx+1
"{T
} W|go*+`W%
2n9E:tc
/** \"E-z.wW=
* @param page |_Y[931<
* The page to set. &"90pBGK
*/ W6Os|z9&|
publicvoid setPage(Page page){ G8JwY\
this.page = page; HxC_nh
} Vd8BQB,Q
.ZK|%VGW
/** G4jaHpPi
* @param users B!Ss
35<
* The users to set. ;'\{T#5)
*/ *mqoyOa
publicvoid setUsers(List users){ >3S^9{d
this.users = users; QU&b5!;&
} fP>K!@!8
4_`ss+gk
/** #>SvYP
* @param userService ]"Do%<