Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <tO@dI$~>
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >'m&/&h
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 |
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 O\oRM2^u}
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分页支持类: ;X+.Ag
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java代码: uARkf'
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package com.javaeye.common.util; vN]_/T+
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import java.util.List; D5Jg(-
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publicclass PaginationSupport { Az(,Q$"|5
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publicfinalstaticint PAGESIZE = 30; ,'<NyA><
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privateint pageSize = PAGESIZE; #PC*l\
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privateList items; !Dc;R+Ir0!
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privateint totalCount; ~rq:I<5
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privateint[] indexes = newint[0]; Jp8,s%
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privateint startIndex = 0; B"88 .U}$
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public PaginationSupport(List items, int ;$ ]a.9
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totalCount){ /r&4< @
setPageSize(PAGESIZE); SEu:31k{o
setTotalCount(totalCount); pp#!sRUKPV
setItems(items); Xrc{wDn
setStartIndex(0); -nD}k
} S,'ekWVD
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public PaginationSupport(List items, int TgLr4Ex
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totalCount, int startIndex){ MCXt,`}[
setPageSize(PAGESIZE); 8{%&P%vf
setTotalCount(totalCount); tmeg=U7
setItems(items); 3fE0cVG*
setStartIndex(startIndex); XCgC^c'
} JHg;2xm"<K
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public PaginationSupport(List items, int VsL*&Fk
)$pqe|,
totalCount, int pageSize, int startIndex){ P;X0L{u0H
setPageSize(pageSize); 6%o@!|=I
setTotalCount(totalCount); uzp\<\d-t
setItems(items); g<w1d{Td
setStartIndex(startIndex); d;3f80Kd*
} ^"uD:f)
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publicList getItems(){ iHdX
return items; <P*7u\9&
} tqt~F2u
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publicvoid setItems(List items){ wk=s3^
this.items = items; x6\^dVR}
} gA5DEit
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publicint getPageSize(){ pJo4&Ff
return pageSize; '7@Dw;
} xkkG#n)
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publicvoid setPageSize(int pageSize){ 0G'v4Vj0'
this.pageSize = pageSize; sAK&^g
} dJb7d`
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publicint getTotalCount(){ i4SWFa``
return totalCount; M%!j\}2A
} mkgL/h*
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publicvoid setTotalCount(int totalCount){ <BdC#t:*L
if(totalCount > 0){ '&]6(+I>
this.totalCount = totalCount; d%!yFix;<
int count = totalCount / L<Z2
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pageSize; %yR80mn8
if(totalCount % pageSize > 0) -H5-6w$
count++; N>@.(f&w
indexes = newint[count];
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for(int i = 0; i < count; i++){ $M|vIw{#
indexes = pageSize * E*v+@rv
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} LG?b]'#
}else{ bvJ*REPL?
this.totalCount = 0; +xr;X 9
} 1aUu:#c
} #yCnM]cEn
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publicint[] getIndexes(){ PhmtCp0-7-
return indexes; /sSif0I24
} C+C1(b;1
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publicvoid setIndexes(int[] indexes){ :yOJL [x
this.indexes = indexes; ^<aj~0v
} a
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publicint getStartIndex(){ I%0J=V;o{
return startIndex; #vR5a}BAk
} %nkbQ2^
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publicvoid setStartIndex(int startIndex){ ?Xp+5{
if(totalCount <= 0) c,*a|@
this.startIndex = 0; s6oIj$
elseif(startIndex >= totalCount) 368H6 Jj
this.startIndex = indexes s%N6^}N
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[indexes.length - 1]; !:D,|k\m
elseif(startIndex < 0) NE@P8pQ>
this.startIndex = 0; %1i *Y*wg
else{ .n}k,da@(
this.startIndex = indexes I=8MLv
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[startIndex / pageSize]; tqU8>d0^
} d^|r#"o[
} L%.=SbmS
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publicint getNextIndex(){ A+hT2Ew@t}
int nextIndex = getStartIndex() + &([Gc+"5E.
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pageSize; 3cFvS[JG
if(nextIndex >= totalCount) :XO7#P
return getStartIndex(); c{/KkmI
else ;:Y/"5h
return nextIndex; :*Z@UY
} 8WG_4e
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publicint getPreviousIndex(){ 2\[
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int previousIndex = getStartIndex() - e" p5hpl
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pageSize; pf_`{2.\uO
if(previousIndex < 0) \j vS`+
return0; 3,@|kN<
else Z^yn S
return previousIndex; R)GDsgXy
} sO&eV68
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抽象业务类 w"h'rw
java代码: m^a0JR}u9
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/** OKNGV,{`
* Created on 2005-7-12 |Lz7}g=6
*/ .@f)#2
package com.javaeye.common.business; "(E%JAwZ^W
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import java.io.Serializable; 2{)<Df@
import java.util.List; atfK?VK#
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import org.hibernate.Criteria; FVoKNaK-
import org.hibernate.HibernateException; +hMF\@
import org.hibernate.Session; NJ!}(=1|K
import org.hibernate.criterion.DetachedCriteria; D+Z,;XZ
import org.hibernate.criterion.Projections; vP/sG5$x
import
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org.springframework.orm.hibernate3.HibernateCallback; hmtDw,j
import !9=Y(rb
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org.springframework.orm.hibernate3.support.HibernateDaoS r Ww.(l
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upport; X#u< 3<P
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import com.javaeye.common.util.PaginationSupport; cN#f$
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public abstract class AbstractManager extends [AAIBb+U
@S Quc
HibernateDaoSupport { Y/34~lhyl
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privateboolean cacheQueries = false; <h1J+
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privateString queryCacheRegion; N'0fB`:kz
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publicvoid setCacheQueries(boolean ny+_&l^R~(
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cacheQueries){ _1HEGX\
this.cacheQueries = cacheQueries; !o/;"'&E
} >qynd'eToR
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publicvoid setQueryCacheRegion(String &ETPYf%#
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queryCacheRegion){
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this.queryCacheRegion = R~XNF/QMl
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queryCacheRegion; K|{&SU_m
} q|R$A8)L.
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publicvoid save(finalObject entity){ D$bJ s O
getHibernateTemplate().save(entity); <e' l"3+9(
} vTYgWR,h
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publicvoid persist(finalObject entity){ \E2S/1p
getHibernateTemplate().save(entity); h>jp.%oOu
} [IW6F
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publicvoid update(finalObject entity){ B7BikxUa
getHibernateTemplate().update(entity); Ty"=3AvRLV
} k.w}}78N2N
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publicvoid delete(finalObject entity){ ]7_O#MY1
getHibernateTemplate().delete(entity); @NJJ
} ` oXL
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publicObject load(finalClass entity, >oc&hT
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finalSerializable id){ 7)v`l1
return getHibernateTemplate().load q
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(entity, id); f%TP>)jag!
} u:O6MO9^
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publicObject get(finalClass entity, E 5bo60z
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finalSerializable id){
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return getHibernateTemplate().get _<G%
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(entity, id); ~6:y@4&F
} p`LPO
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publicList findAll(finalClass entity){ r=pb7=M#LN
return getHibernateTemplate().find("from vE+OL8 V
$;%dQ!7*
" + entity.getName()); 834dsl+U
} ,4z?9@wQ
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publicList findByNamedQuery(finalString IpMZ{kJlv`
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namedQuery){ Y=N; Bj
return getHibernateTemplate <E&"]
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().findByNamedQuery(namedQuery); qfzT8-Y
} ;Cqjg.wkB
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publicList findByNamedQuery(finalString query, B[Fuy y?
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finalObject parameter){ Ayi
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return getHibernateTemplate az ?2
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().findByNamedQuery(query, parameter); Eq?d+s>
} dd%-bI^
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publicList findByNamedQuery(finalString query, = g)G!
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finalObject[] parameters){ Nd4!:.
return getHibernateTemplate )<1}`9G
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().findByNamedQuery(query, parameters); H/ 6GD,0
} pu*vFwZ
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publicList find(finalString query){ qP0_#l&
return getHibernateTemplate().find j?n:"@!G/
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(query); #%i-{t+_>
} NTtRz(
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publicList find(finalString query, finalObject [#R<Z+c
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parameter){ (^Kcyag4
return getHibernateTemplate().find D;0xROW8{
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(query, parameter); rpT{0>5
} UMJ>6Ko8
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public PaginationSupport findPageByCriteria Rl""
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(final DetachedCriteria detachedCriteria){ {E~MqrX
return findPageByCriteria pQY.MZSA
}3Y3f).ZW
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?=uw0~O[
} b]h]h1~hHH
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public PaginationSupport findPageByCriteria 4;ig5'U,
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(final DetachedCriteria detachedCriteria, finalint Y Hv85y
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startIndex){ zoV-@<Eh
return findPageByCriteria L.xzI-I@D
SAEr $F^
(detachedCriteria, PaginationSupport.PAGESIZE, &n:F])`2
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startIndex); ]{[VTjC7rY
} Z<#beT6
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public PaginationSupport findPageByCriteria $bU|'}QR
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(final DetachedCriteria detachedCriteria, finalint &:` 7
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pageSize, "=W7=V8w
finalint startIndex){ 9J?G"JV?
return(PaginationSupport) RkJ\?
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getHibernateTemplate().execute(new HibernateCallback(){ { [4Y(l1
publicObject doInHibernate o"x&F
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(Session session)throws HibernateException { X3:-+]6,d
Criteria criteria = |^ml|cb
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detachedCriteria.getExecutableCriteria(session); iD|"} }01
int totalCount = PaEsz$mgy
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((Integer) criteria.setProjection(Projections.rowCount x=qACoq
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()).uniqueResult()).intValue(); 15r<n
criteria.setProjection `
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(null); E$FXs~a
List items = `oh'rm3'8
-NVk>ENL4
criteria.setFirstResult(startIndex).setMaxResults zy#E qv
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(pageSize).list(); NDRk%_Eu(
PaginationSupport ps = O329Bkg
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new PaginationSupport(items, totalCount, pageSize, &Sc}3UI/F
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startIndex); C<6IiF[>%
return ps; @Ns^?#u~
} m4nJ9<-
}, true); xnu|?;.}!
} +MQf2|--
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public List findAllByCriteria(final Fa9]!bW
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DetachedCriteria detachedCriteria){ t9PS5O ;
return(List) getHibernateTemplate ?#\?&uFJ}
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().execute(new HibernateCallback(){ 8jjJ/Mz`
publicObject doInHibernate -{ZTp8P>
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(Session session)throws HibernateException { +gOCl*L
Criteria criteria = *kxk@(lT?
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detachedCriteria.getExecutableCriteria(session); "_C^Bc
return criteria.list(); yi7-[W}
} nrA}36 E
}, true); [6
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} {61NLF\0H
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public int getCountByCriteria(final ''wWw(2O
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DetachedCriteria detachedCriteria){ QHsS|\u
Integer count = (Integer) jjz<V(Sk
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getHibernateTemplate().execute(new HibernateCallback(){ }qW%=;!
publicObject doInHibernate 5in6Y5c kj
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(Session session)throws HibernateException { P7E}^y`e
Criteria criteria = [(`T*c.#.X
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detachedCriteria.getExecutableCriteria(session); q!<`ci,uS
return R6)p4#|i
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criteria.setProjection(Projections.rowCount &tQ,2RT
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()).uniqueResult(); ,I@4)RSAH|
} uwWfL32
}, true); .Kq>/6
return count.intValue(); (XRj##G{
} T |'Ur#
} vUgLWd
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用户在web层构造查询条件detachedCriteria,和可选的 &6MGPh7T
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _:M6~XHo
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PaginationSupport的实例ps。 & HphE2 h
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ps.getItems()得到已分页好的结果集 %o#D"
ps.getIndexes()得到分页索引的数组 X\
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ps.getTotalCount()得到总结果数 N(}7M~m>
ps.getStartIndex()当前分页索引 &N*S
ps.getNextIndex()下一页索引 0wZLkU_(
ps.getPreviousIndex()上一页索引 ?GD{}f33
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 n1uJQt
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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 w>H!H6Q
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一下代码重构了。 x7Ly,
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我把原本我的做法也提供出来供大家讨论吧: MJV&%E6{:{
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首先,为了实现分页查询,我封装了一个Page类: N iNZh;
java代码: '_r|L1
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/*Created on 2005-4-14*/ '/;#{("
package org.flyware.util.page; *-_` xe
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/** 1uMnlimr
* @author Joa >V87#E
* -&))$h3o\
*/ >S5D-)VX
publicclass Page { YV{^S6M
p5)A"p8"9,
/** imply if the page has previous page */ y
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privateboolean hasPrePage; 0gO2^m)W
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/** imply if the page has next page */ b
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privateboolean hasNextPage; 8DLR
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/** the number of every page */ cdzzS?$)
privateint everyPage; bU2)pD!N
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/** the total page number */ )V)4N[?GC
privateint totalPage; Q`AJR$L
,O3"r;
/** the number of current page */ #hR}7K+@
privateint currentPage; $L:g7?)k
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/** the begin index of the records by the current Iy|]U&`
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query */ xE;fM\7pu
privateint beginIndex; xC<OFpI\
NO`a2HR$
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/** The default constructor */ G0> 'H1 Z
public Page(){ b4ORDU
NqhRJa63
} R\0]\JEc
1ZhJ?PI,9{
/** construct the page by everyPage :$/lGIz
* @param everyPage ;13lu1
* */ (.%:Q0i1
public Page(int everyPage){ biKpV?Dp
this.everyPage = everyPage; cQgmRHZ]
} )u\"xxcV
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/** The whole constructor */ A8c'CMEm
public Page(boolean hasPrePage, boolean hasNextPage, D9#e2ex]
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int everyPage, int totalPage, ]Z<{
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int currentPage, int beginIndex){ s'~_pP
this.hasPrePage = hasPrePage; qh F/iUE
this.hasNextPage = hasNextPage; Om>6<3n
this.everyPage = everyPage; JWMIZ{/M
this.totalPage = totalPage; kwGj7'
this.currentPage = currentPage; m'aw`?
this.beginIndex = beginIndex; T{sw{E*
} K Qub%`n
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/** &z1r$X.AW
* @return !c(B^E
* Returns the beginIndex. 7:M%w'oR
*/ qx0J}6+NlU
publicint getBeginIndex(){ I \vu?$w
return beginIndex; 6G@_!i*2F
} Ms^Y:,;Hi
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/**
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* @param beginIndex |P5?0{
* The beginIndex to set. 86IAAO`#
*/ eSa ]6
publicvoid setBeginIndex(int beginIndex){ xiA9X]FB
this.beginIndex = beginIndex; _6=6 b!hD
} G_j`6v)
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/** 0qJ(3N
* @return bG.aV#$FIg
* Returns the currentPage. N1#*~/sXh
*/ $D9JsUij
publicint getCurrentPage(){ F P
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return currentPage; 3@ay9!Xq
} YroKC+4"i
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/** z%*ZmF ^K
* @param currentPage )vuxy
* The currentPage to set. fKrOz!b
*/ [|k@Suv |z
publicvoid setCurrentPage(int currentPage){ O$$s]R6
this.currentPage = currentPage; V)N9V|O'
} iCl,7$[*
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/** De4+4&
* @return !R)v2Mk|
* Returns the everyPage. UnW,|n8
*/ P}?,*'b
publicint getEveryPage(){ _4%+TN6z
return everyPage; V\ARe=IWM
} og2]B\mN4
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/** j24BB}mBB
* @param everyPage DOU\X N
* The everyPage to set. 5Z`f)qE
*/ 5G\vV]RR&
publicvoid setEveryPage(int everyPage){ G9Xrwk<g4
this.everyPage = everyPage; YdE$G>&em
} d['BtVJ
s=U_tfpH
/** ZL1[Khr,s
* @return lXv{+ic
* Returns the hasNextPage. "V?U^L>SF
*/ D_@r_^}
publicboolean getHasNextPage(){ q'K=Ly+
return hasNextPage; r%_)7Wk*
} ZZl)p\r
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/** JRU)AMMU&
* @param hasNextPage W J^r~*r
* The hasNextPage to set. B[cZEFo\
*/ 61!R-
publicvoid setHasNextPage(boolean hasNextPage){ }ZvL%4jT
this.hasNextPage = hasNextPage; Bz7T1B&to
} $+7MY-9T
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/** 6AZ/whn#
* @return Pfi '+I`s
* Returns the hasPrePage. AbLOq@lrK
*/ ;znIY&Z
publicboolean getHasPrePage(){ tM{t'WU
return hasPrePage; eCk}B$ 2
} NsWyxcty
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/** Xv=n+uo
* @param hasPrePage E(TL+o
* The hasPrePage to set. 193Q
*/ nJ'O(Wh,)
publicvoid setHasPrePage(boolean hasPrePage){ 10}\7p8
this.hasPrePage = hasPrePage; XQlK}AK
} g-Z>1V
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/** ":eHR}Hzx
* @return Returns the totalPage. XY0Gjo0
* }1d
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*/ HAN#_B1.
publicint getTotalPage(){ `C] t2^
return totalPage; _j<46^
} #Du1(R
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/** cq@8!Eu w]
* @param totalPage h7I_{v8
* The totalPage to set. qrm~=yU%
*/ mpXco *!_
publicvoid setTotalPage(int totalPage){ Ay2Vz>{
this.totalPage = totalPage; Tfs7SC8ta
} pS*vwYA
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} $S=lm {
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 M<g>z6
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个PageUtil,负责对Page对象进行构造: 9$UjZ$ v
java代码: .T4"+FTzP
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/*Created on 2005-4-14*/ {gK
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package org.flyware.util.page; M/R#f9W
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import org.apache.commons.logging.Log; h_x"/z&
import org.apache.commons.logging.LogFactory; h"]v+u`!SM
3D;\V&([
/** f:Ju20D
* @author Joa @x"vGYKd
* LnrR#fF]Z
*/ rv:,Os_
publicclass PageUtil { c?>Q!sC
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privatestaticfinal Log logger = LogFactory.getLog :eei<cn2
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(PageUtil.class); i&{8a3B
*sZOws<
/** Ok2k;
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* Use the origin page to create a new page D|`[ [
* @param page lj'c0k8
* @param totalRecords <iJ->$
* @return )#IiHBF
*/ xREqcH,vU
publicstatic Page createPage(Page page, int @6}c\z@AxM
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totalRecords){ kM]?
return createPage(page.getEveryPage(), XvZg!<*OH
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page.getCurrentPage(), totalRecords); 4+' yJ9~,B
} {u3^#kF
:}e*3={4
/** T~=NY,n
* the basic page utils not including exception u{tjB/K&
.2[>SI
handler `!>zYcmT
* @param everyPage :=UeYm
@
* @param currentPage Lt|k}p@]
* @param totalRecords K,?M5n '
* @return page I_'vVbK+>
*/ %L<VnY#%u
publicstatic Page createPage(int everyPage, int Wi
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currentPage, int totalRecords){ s1:UCv-%
everyPage = getEveryPage(everyPage); $zyY"yWRZ
currentPage = getCurrentPage(currentPage); <yE(p
int beginIndex = getBeginIndex(everyPage, 0[);v/@Ho
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currentPage); b3<<4Vf
int totalPage = getTotalPage(everyPage, g9'50<|J
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totalRecords); E;| q
boolean hasNextPage = hasNextPage(currentPage, kO~xE-(=
2,E&}a|;b
totalPage); Pm%ZzU
boolean hasPrePage = hasPrePage(currentPage); h,rGa\X~0
=pN?h<dc
returnnew Page(hasPrePage, hasNextPage, =JX.*
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everyPage, totalPage, N[){yaj
currentPage, o/2\8
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beginIndex); v3Te+oLg
} Hx62x X
z!D >l
privatestaticint getEveryPage(int everyPage){ 3yZtyXRPn
return everyPage == 0 ? 10 : everyPage; (ZT*EFhb(
} ol:,02E&
P\*-n"
privatestaticint getCurrentPage(int currentPage){ "Yq-s$yBi
return currentPage == 0 ? 1 : currentPage; q~_Nv5r%O
} ~}$:iyJV(>
J0C<Qb[
privatestaticint getBeginIndex(int everyPage, int }\OLBg/
+mMn1&
currentPage){ (
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return(currentPage - 1) * everyPage; 4Y Xtl+G
} xJJlV P
y? )v-YGu
privatestaticint getTotalPage(int everyPage, int mQ('X~l
EYcvD^!1g
totalRecords){ TB*g$*
int totalPage = 0; 1CFrV=d
toX4kmC
if(totalRecords % everyPage == 0) l/DV
?27
totalPage = totalRecords / everyPage; s7D_fv4e
else 0F0V JE
totalPage = totalRecords / everyPage + 1 ; 8Rc4+g
FWq6e,
return totalPage; 0r_8/|N#
} f&7SivS#
MS_&;2
privatestaticboolean hasPrePage(int currentPage){ X+?*Tw!\
return currentPage == 1 ? false : true; B#B$w_z
} J55K+
zTAt% w5
privatestaticboolean hasNextPage(int currentPage, Haaungb"
<@A/`3_O)
int totalPage){ L!3{ASIN0
return currentPage == totalPage || totalPage == cx1U6A+
mhnD1}9,Ih
0 ? false : true; `0=0IPVd
} o3]B/
gmj
a2F,
c zL[W2l
} jf$6{zO6j
X>wB=z5PXK
!5?#^q
#-
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/FkLZm
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 (|bMtT?"x
}rn}r4_a
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Kbg`ZO*
q4xB`G
做法如下: [I4K`>|Z
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4)]g=-3
Olj]A]v}
的信息,和一个结果集List: n&r-
java代码: e\%QHoi>u
y~SFlv36
7I&7YhFI
/*Created on 2005-6-13*/ {QM;%f
package com.adt.bo; )>\J~{
&Sa<&2W4S
import java.util.List; \Y
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zb?wlfT
import org.flyware.util.page.Page; I{_St8
PxfeU2^{0
/** SL hki)|
* @author Joa y$r9Y!?s
*/ U^+9l?ol
publicclass Result { ?"{+m
!6@xX08z
private Page page; h$f/NSct2
Mpk^e_9`<
private List content; wf=#w}f
uZ]B ?Z%y#
/** bhOyx
* The default constructor 5y(irbk7
*/ YRG+I GX
public Result(){ ::j'+_9
super(); bsuUl*l)
} bv\V>s
xGk@BA=0<
/** n{r+t=X
* The constructor using fields -102W{V/T
* s|pb0
* @param page ~XsS00TL`G
* @param content ~BERs;4
*/ \xDu#/^
public Result(Page page, List content){ [9BlP
this.page = page; "2HRuqf
this.content = content; d%t]:41=Z
} umcbIi('
$-=aqUU
/** HoH3.AY X
* @return Returns the content. @Sq=#f/=
*/ 7@fd[
publicList getContent(){ 6N~ jt
return content; >,@Fz)\:{'
} <j ;HRm
@tEVgyN
/** E;VB oN [
* @return Returns the page. ;FMK>%Zq
*/ ZNOoyWYi5
public Page getPage(){ pr;<n\Y{
return page; w?jmi~6
} 7 z<!2
/nv1.c)k
/** reu[}k ~
* @param content IH\k_Yf#u
* The content to set. iBp 71x65
*/ P^rSpS9
public void setContent(List content){ E0xUEAO
this.content = content; $rFv(Qc^=
} }2`S@Rq.WW
By3dRiM=,2
/** F|xXMpC.f
* @param page @h>#cwhU
* The page to set. zHb<YpU
*/ d2.n^Q"?3
publicvoid setPage(Page page){ "{z9 L+
this.page = page; `3pe\s
} j@GMZz<
} m9#u.Q*
U|{WtuR
:&?# ~NFH
D1o 8Wo
ni2H~{]z
2. 编写业务逻辑接口,并实现它(UserManager, 82O`<Ci
~gI%
UserManagerImpl) w2+RX-6Ie
java代码: Kw!`u^>
*9PS2*n
hXz"}X n
/*Created on 2005-7-15*/ 9?,n+
package com.adt.service; $XyGCn
}Lb];hww1
import net.sf.hibernate.HibernateException; Wv=L_E_
,Yi =s;E
import org.flyware.util.page.Page; I=(O,*+PQ
:6HMb^4
import com.adt.bo.Result; )&_{m
K
zE<vFP-1v
/** CvbY2_>Nh
* @author Joa ec=4L@V*
*/ {E 6W]Mno
publicinterface UserManager { ?ZDx9*f
`Z%XA>
public Result listUser(Page page)throws *2:)Rf
5VG@Q%
HibernateException; B@iIj<p~
#y>oCB`EM
} cgz'6q'T
}PED#Uv
^1*p]j(
V{d"cs>9
n0vPW^EQ
java代码: ^f<f&V
5)T{iPU%X
!Id F6 %
/*Created on 2005-7-15*/ cq[}>5*k
package com.adt.service.impl; R`1$z8$
zR{TWk]
import java.util.List; gvcT_'
f^$\+H"W
import net.sf.hibernate.HibernateException; \s~W;m
3J(STIxg
import org.flyware.util.page.Page; kY_UY~E
import org.flyware.util.page.PageUtil; qZ1fQN1yG
0
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import com.adt.bo.Result; YLFTf1G9
import com.adt.dao.UserDAO; c#Y9L+O
import com.adt.exception.ObjectNotFoundException; /OxF5bN2
import com.adt.service.UserManager; ^eZqsd8a
jBE=Ij
/** DcOu=Y> 1
* @author Joa OcSLRN?t
*/ (>;~((2
publicclass UserManagerImpl implements UserManager { \H" (*["&
IL>g-
private UserDAO userDAO; Wq,UxMz
0hNc#x6
/** .Dx]wv
* @param userDAO The userDAO to set. ||!k 3t#<
*/ ^8MgNVoJ)
publicvoid setUserDAO(UserDAO userDAO){ |=h>3Z=r!
this.userDAO = userDAO; `q
xg
} As)-a5!
,%,}[q?]d
/* (non-Javadoc) =%]dk=n?TN
* @see com.adt.service.UserManager#listUser ~&yaIuW<
x1Si&0T0P<
(org.flyware.util.page.Page) ]h|GaHiE
*/ =3(
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public Result listUser(Page page)throws f3596a
E3gQ`+wNg?
HibernateException, ObjectNotFoundException { `mWg$e,
int totalRecords = userDAO.getUserCount(); 9]7^/g*!
if(totalRecords == 0) vkt)!hl `
throw new ObjectNotFoundException -7pZRnv
T
7
hC]R
("userNotExist"); F`38sq
page = PageUtil.createPage(page, totalRecords); lq%s/l
List users = userDAO.getUserByPage(page); #[i({1`^L
returnnew Result(page, users); xknP
`T
} =E,*8O]
_Y~+ #Vc
} .79'c%3}
}2h~o~
YE^|G,]
|5FyfDaFBX
^(6.M\Q
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ml3]CcKn
/#Xz+#SqY
询,接下来编写UserDAO的代码: 9wI1/>
3. UserDAO 和 UserDAOImpl: RWoa'lnu
java代码: =nY*,Xu<
@0)bY*njj
2smLv1w@
/*Created on 2005-7-15*/ : 0%V:B
package com.adt.dao; ( E0be.
k@wxN!w;
import java.util.List; y\@XW*_?
0<P
-` |X
import org.flyware.util.page.Page; R"82=">v
RQh4RUm
import net.sf.hibernate.HibernateException; icnp^2P
$:<KG&Br
/** #=zh&`
* @author Joa IPY@9+]
*/ M<)HJ lr
publicinterface UserDAO extends BaseDAO { gGZ$}vX
GbMSO
publicList getUserByName(String name)throws
zx\?cF
ikofJl]9
HibernateException; z}pdcQl#
l9SbuT$U
publicint getUserCount()throws HibernateException; hx:x5L>
\Mi y+<8$
publicList getUserByPage(Page page)throws 9 s>JdAw?
XLzHm&;
HibernateException; ~A6QX8a
#^eviF8
} 8WaVs 6
7[8PSoo
J.*dA j
jT'1k[vJj
hDfsqSK0 /
java代码: cQN}z
Ke
;up89a-,9
@y}1%{,%
/*Created on 2005-7-15*/ h"q`gj
package com.adt.dao.impl; ymzlRs1^Ct
N.3M~0M*
import java.util.List; }9@,EEhg
*%Q!22?6F
import org.flyware.util.page.Page; oU{m\r
2AU_<Hr6
import net.sf.hibernate.HibernateException; ^S[Mg6J
import net.sf.hibernate.Query; x==%BBnO%
b~cN#w
#
import com.adt.dao.UserDAO; ku?i[Th
WzZb-F
/** Z.rKV}yjY
* @author Joa 3VKArv-
*/ `F(KM '
public class UserDAOImpl extends BaseDAOHibernateImpl 7zy6`OP
bl:.D~@
implements UserDAO { jYuH
zf
&grT}
/* (non-Javadoc) -4"E]f
* @see com.adt.dao.UserDAO#getUserByName Oi=kL{DG:s
VBsS1!g
(java.lang.String) O~ w&4F;{
*/ Rsqb<+7
publicList getUserByName(String name)throws ULAAY$o@5
Ga$+x++'*
HibernateException { Xgc@cwd
String querySentence = "FROM user in class qifX7AXHr
-Vw,9VCF
com.adt.po.User WHERE user.name=:name"; ,GGr@})
Query query = getSession().createQuery ?!8M
I,c/
r1xNU0A
(querySentence); V[Auw3)
query.setParameter("name", name); NtSa#$A
return query.list(); #(!>
} lcyan
vMDV%E S1t
/* (non-Javadoc) <+pwGKtD
* @see com.adt.dao.UserDAO#getUserCount() l *.#g
*/ AEhh
6v
publicint getUserCount()throws HibernateException { >STWt>s
int count = 0; @)|62Dv /
String querySentence = "SELECT count(*) FROM E_7N^htv
PJS\> N&u
user in class com.adt.po.User"; = K}5 fe
Query query = getSession().createQuery IIs'm!"Y>
WHMt$W}%
(querySentence); d z&8$(f,
count = ((Integer)query.iterate().next i5q
VQo
wjQu3 ,Cj
()).intValue(); ojUBa/
return count; j:\MrYt0H
} i\2~yXw\
Z6A*9m
/* (non-Javadoc) "\)j=MI8u+
* @see com.adt.dao.UserDAO#getUserByPage &8z`]mB{t
n<uF9N<
(org.flyware.util.page.Page) 4tof[n3us
*/ z45ImItH
publicList getUserByPage(Page page)throws $9j\sZj&
OT&J OTk\
HibernateException { b_:]Y<{> f
String querySentence = "FROM user in class m "h{HgJd
seB ^o}
com.adt.po.User"; a9` E&Q}z
Query query = getSession().createQuery v&D^N9hy9
tc.R(F96
(querySentence); 5ZSV)$t
query.setFirstResult(page.getBeginIndex())
8dNwi&4
.setMaxResults(page.getEveryPage()); 7q^osOj"
return query.list(); y08.R.
l
} |Xlpgdiu
4(f[Z9 iZ]
} D({%FQ"
}v"X.fa^
OV_Y`u7YR
nK)U.SZ
"FwbhD0Gb
至此,一个完整的分页程序完成。前台的只需要调用 JUt
7
|^[]Oy=
userManager.listUser(page)即可得到一个Page对象和结果集对象 # 4L[8(+V
yn)K1f^
的综合体,而传入的参数page对象则可以由前台传入,如果用 O=?WI
J 6D?$
webwork,甚至可以直接在配置文件中指定。 D4$;jz,,
wKIQK!B)mF
下面给出一个webwork调用示例: =c"`>Vi@d
java代码: -1;BwlL
bx_`S#*N
NiQ`,Q$B
/*Created on 2005-6-17*/ ?|s1Cuc
package com.adt.action.user; [I^>ji0V
imv[xBA(d
import java.util.List; <,$(,RX
vd6Y'Zk|F6
import org.apache.commons.logging.Log; MkEr|w'
import org.apache.commons.logging.LogFactory; 0&mOu #l
import org.flyware.util.page.Page; >7[.
{Y
;Kob]b
import com.adt.bo.Result; 01uMbtM
import com.adt.service.UserService; Y?a*-"
import com.opensymphony.xwork.Action; wC+_S*M-K
$6kVhE!;
/** $vlq]6V8
* @author Joa PGF=q|j9K
*/ *7u~`
publicclass ListUser implementsAction{ O0`sg90,C
rlEEf/m:
privatestaticfinal Log logger = LogFactory.getLog o{f|==<t3#
ACxOC 2\n
(ListUser.class); [p^N].K$
X`JWYb4
private UserService userService; "7mYs)=
RB`Emp&T
private Page page; GVP"~I~/:
]r8t^bqe
privateList users; pC2ZN
[DpGL/Y.
/* e[.c^Hw
* (non-Javadoc)
jT}3Zn
* A[`c2v-hF
* @see com.opensymphony.xwork.Action#execute() QV,X> !Nz
*/ 'Alt+O_
publicString execute()throwsException{ J6r"_>)z
Result result = userService.listUser(page); bw\fKZ
page = result.getPage(); &MKG#Y}
users = result.getContent(); 3z';Zwz &X
return SUCCESS; +LuGjDn0
} EhL
8rR
KJ M:-z@
/** ufyqfID
* @return Returns the page. eM
Ym@~4
*/ Y /$`vgqs
public Page getPage(){ =@q 9,H
return page; q<