Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 w|-3X
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 jt on \9
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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 U`i5B;k}-
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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 26rg-?;V^
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分页支持类: z'_Fg0kR{
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java代码: uW(-?
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package com.javaeye.common.util; Ze eV-
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import java.util.List; JiaR*3#
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publicclass PaginationSupport { ERV]N:(
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publicfinalstaticint PAGESIZE = 30; 2CO/K_Q
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privateint pageSize = PAGESIZE; o5tCbsHj-
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privateList items; ,UMr_ e{|
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privateint totalCount; /;#kV]nF
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privateint[] indexes = newint[0]; M`H#Qo5/
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privateint startIndex = 0; q2vD)r
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public PaginationSupport(List items, int UxTLr-db^
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totalCount){ k.ou$mIY
setPageSize(PAGESIZE); X3l>GeUi
setTotalCount(totalCount); /{i~-DVME
setItems(items);
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setStartIndex(0); @%Ld\8vdfJ
} \Y)HSJR;e
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public PaginationSupport(List items, int ~R
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totalCount, int startIndex){ #T_!-;(Z
setPageSize(PAGESIZE); #ODP+>-IjB
setTotalCount(totalCount); T>&
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setItems(items); 2{rWAPHgz
setStartIndex(startIndex); 5-|!mSd
} DQQ]grU
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public PaginationSupport(List items, int +?{"Q#.>;
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totalCount, int pageSize, int startIndex){ S{+t>en
setPageSize(pageSize); x|0C0a\"A
setTotalCount(totalCount); 2`$*HPj+G
setItems(items); gT+g@\u[
setStartIndex(startIndex); a|7C6#iz$
}
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@.eN+o9|
publicList getItems(){ @ep.wW
return items; N>H@vt~
} 3U@jw,K!{A
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publicvoid setItems(List items){ =6[.||9
this.items = items; u?Ffqt9'
} ?s^qWA
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publicint getPageSize(){ ,<rC,4-F<
return pageSize; h+Co:pr
} */;7Uv7
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publicvoid setPageSize(int pageSize){ IgX &aW
this.pageSize = pageSize; 6!m#;8 4
} j 2ag
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publicint getTotalCount(){ f8:nKb>nq$
return totalCount; hJEd7{n
} ka9@7IFM
@Lnv
publicvoid setTotalCount(int totalCount){ HoGYgye=
if(totalCount > 0){ MYS`@%ZV#k
this.totalCount = totalCount; p3=Py7iz
int count = totalCount / m)tu~neM
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pageSize; Ss>pNH@c
if(totalCount % pageSize > 0) |U|>YA1[b
count++; J\@6YU[A
indexes = newint[count]; R.^]{ 5
for(int i = 0; i < count; i++){ duY?LJ @g
indexes = pageSize * i/9iM\2
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i; oP`l)`
} GTP'js
}else{ 6'Q{xJe?
this.totalCount = 0; tAAMSb9[d
} n~I-mR)"
} Z}+}X|
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publicint[] getIndexes(){ {<,%_pJR
return indexes; r].n=455[
} ^9Pr`\
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publicvoid setIndexes(int[] indexes){ "v1{
this.indexes = indexes; Ek{Q NlQ]4
} 0caZ_-zU
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publicint getStartIndex(){ &b} \).5E
return startIndex; <YaT r9%w
} LiG$M{ 0
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publicvoid setStartIndex(int startIndex){ vjS`;^9
if(totalCount <= 0) }>@\I^Xm,
this.startIndex = 0; Tv=lr6t8
elseif(startIndex >= totalCount) q+L'h8
this.startIndex = indexes k1wIb']m]z
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[indexes.length - 1]; #Z%"
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elseif(startIndex < 0) hq=;ZI
this.startIndex = 0; I1<WHq
else{ 6'# 5Dqw"r
this.startIndex = indexes TjUwe@&Rw
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[startIndex / pageSize]; lFzVd
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} =1IK"BA2?
} B>53+GyMV
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publicint getNextIndex(){ 2&1mI>:F
int nextIndex = getStartIndex() + 2aYBcPFQh#
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pageSize; xo[o^go
if(nextIndex >= totalCount) E 2nz
return getStartIndex(); ? o"
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else W"NI^OX
return nextIndex; sA2-3V<t8
} *] ihc u
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publicint getPreviousIndex(){ xp^RAVXq`
int previousIndex = getStartIndex() - \&Yn)|!
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pageSize; 4aXIRu%#7
if(previousIndex < 0) _**Nlp*%
return0; 8
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else ,2M}qs"P7G
return previousIndex; [H h-F#|R
} b>-DX
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} nR_Zrm
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抽象业务类 QOWGQl%!
java代码: Bj@>iw?g'
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/** (0 T!-hsP
* Created on 2005-7-12 \L Q+
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*/ 8 .%0JJ .3
package com.javaeye.common.business; `!]|lI!GW
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import java.io.Serializable; AQ,lLn+
import java.util.List; ;(i6 X)
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import org.hibernate.Criteria; (nqry[g&
import org.hibernate.HibernateException; *ID=X!v
import org.hibernate.Session; UoT`/.
import org.hibernate.criterion.DetachedCriteria; ]\pi!oa
import org.hibernate.criterion.Projections; =D1
import _p )NZ7yC
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org.springframework.orm.hibernate3.HibernateCallback; @v)Z>xv
import Gx C+lqH#
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org.springframework.orm.hibernate3.support.HibernateDaoS s$M(-"mg
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upport; iWCYK7c@.-
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import com.javaeye.common.util.PaginationSupport; h^3gYL7O6
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public abstract class AbstractManager extends h:4(Gm;
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HibernateDaoSupport { '/>Mr!H#
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privateboolean cacheQueries = false; "^]gI Qc
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privateString queryCacheRegion; CS[]T9|_
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publicvoid setCacheQueries(boolean NUsxMhP
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cacheQueries){ +x%u?ZR
this.cacheQueries = cacheQueries; io#}z4"'qY
} KIF9[/P
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publicvoid setQueryCacheRegion(String |
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queryCacheRegion){ u^2`$W
this.queryCacheRegion = alb3oipOB
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queryCacheRegion; w"R<8e=
} %-n)L
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publicvoid save(finalObject entity){ o#qdgZ
getHibernateTemplate().save(entity); !5*VBE\
} dseI~}
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publicvoid persist(finalObject entity){ 3&-rOc
getHibernateTemplate().save(entity); 7By7F:[ b
} ?|M-0{
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publicvoid update(finalObject entity){ !f~a3 {;j
getHibernateTemplate().update(entity); R~g|w4a@sC
} !gXxM,R
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publicvoid delete(finalObject entity){ '?rR>$s
getHibernateTemplate().delete(entity); tc~gn!"
} t&U9Z$LS
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publicObject load(finalClass entity, T<]{:\*n
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finalSerializable id){ |
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return getHibernateTemplate().load UQ0!tFx
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(entity, id); 5IU!BQU
} //@6w;P
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publicObject get(finalClass entity, Ct=bZW"j/
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finalSerializable id){ #BRIp(65-6
return getHibernateTemplate().get ?1=.scmgDG
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(entity, id); i c{I
} :w8{BIUN)
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publicList findAll(finalClass entity){ Z %pc"
return getHibernateTemplate().find("from vobC/m
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" + entity.getName()); n.+*_c8 k
} @<W` w
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publicList findByNamedQuery(finalString Jh+;+"
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namedQuery){ P-X|qVNK1Z
return getHibernateTemplate KM &P5}
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().findByNamedQuery(namedQuery); -ssb|r
} 'o&d!
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publicList findByNamedQuery(finalString query, k+_>`Gre}
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finalObject parameter){ eU"yF >6'
return getHibernateTemplate ?+}Su'pv}
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().findByNamedQuery(query, parameter); QQAEG#.5
} "%T~d[M
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publicList findByNamedQuery(finalString query, S.MRL,
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finalObject[] parameters){ FG${w.e<
return getHibernateTemplate k8 #8)d
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().findByNamedQuery(query, parameters); $:s@nKgnD~
} 5AT^puL]]
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publicList find(finalString query){ L@Rgiq|v-|
return getHibernateTemplate().find +s#%\:Y M
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(query); RLf-Rdx/
} nWK8.&{.
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publicList find(finalString query, finalObject xOkdu k]
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parameter){ NVzo)C8kb
return getHibernateTemplate().find .vHHw@
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(query, parameter); yu_PZ"l
} E$%v);u
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public PaginationSupport findPageByCriteria rl.K{Uad
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(final DetachedCriteria detachedCriteria){ 7nPg2K&
return findPageByCriteria 59nRk}^$se
k _t|)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); aQoB1qd8
} Q7x[08TI
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public PaginationSupport findPageByCriteria fDr$Wcd~
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]
(final DetachedCriteria detachedCriteria, finalint #JYl%=#,
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startIndex){ {^oohW -
return findPageByCriteria "e-z2G@z
ue8 @=}
(detachedCriteria, PaginationSupport.PAGESIZE, bB4FjC':
>|S@twy
startIndex); 3nBZ+n4z
} 4$^mLD$>
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public PaginationSupport findPageByCriteria F,vkk{Z>
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(final DetachedCriteria detachedCriteria, finalint +VVn@=&?
">T\]V$R
pageSize, -+ F,L8
finalint startIndex){ IWYQ67Yj
return(PaginationSupport) k*_Gg
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getHibernateTemplate().execute(new HibernateCallback(){ O#.YTTj
publicObject doInHibernate =?|$}vDO[
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(Session session)throws HibernateException { (pH)QG
Criteria criteria = {n>.Y-=
v
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detachedCriteria.getExecutableCriteria(session); 38sLyoG=i
int totalCount = =b66H]h?
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((Integer) criteria.setProjection(Projections.rowCount #j7&2L
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()).uniqueResult()).intValue(); r!b>!
criteria.setProjection "PMJh 3q
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(null); ]$#bNt/p
List items = 2lfEJw($
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criteria.setFirstResult(startIndex).setMaxResults VMABj\yG
Uic
(pageSize).list(); #i~P])%gNP
PaginationSupport ps = HB#!Dv&'
7 Td
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new PaginationSupport(items, totalCount, pageSize, .+(ED
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startIndex); Gt{%O>P8t
return ps; ,i6U*
} QcWg
}, true); @@@}FV&
} !{,2uQXe
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public List findAllByCriteria(final yVVyWte,
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DetachedCriteria detachedCriteria){ nYyKz
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return(List) getHibernateTemplate H6Zo|n
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().execute(new HibernateCallback(){ xVsI#`<a
publicObject doInHibernate h% >ZN-K)
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(Session session)throws HibernateException { ,fiV xn Q
Criteria criteria = qJ5b;=
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detachedCriteria.getExecutableCriteria(session); LV ]10v6
return criteria.list(); BZv:E?1z
} u~,hTY(%
}, true); 5OPvy,e6
} G5|nt#>
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public int getCountByCriteria(final F,as>X#
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DetachedCriteria detachedCriteria){ pzt<[;
Integer count = (Integer) _x|R`1`
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getHibernateTemplate().execute(new HibernateCallback(){ E<D^j^T
publicObject doInHibernate N[-$*F,:_
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(Session session)throws HibernateException { HjzAFXRG
Criteria criteria = qsEFf(9G
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detachedCriteria.getExecutableCriteria(session); gc I<bY
return {oAD;m`
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criteria.setProjection(Projections.rowCount 3rMi:*?
7[ n
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()).uniqueResult(); #'@@P6o5
} 2f{p$YIt
}, true); ]w,|WZm
return count.intValue(); 16N|
} 7}NvO"u
} f/z]kfgw
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用户在web层构造查询条件detachedCriteria,和可选的 'A3*[e|OS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -1hCi!
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PaginationSupport的实例ps。 Wm}T=L`
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ps.getItems()得到已分页好的结果集 -|u
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ps.getIndexes()得到分页索引的数组 nm_taER
ps.getTotalCount()得到总结果数 U:@tdH+A7
ps.getStartIndex()当前分页索引 jT]R"U/Q
ps.getNextIndex()下一页索引 ?N9Z;_&^.
ps.getPreviousIndex()上一页索引 00SS<iX
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Kc@Sw{JR#7
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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 ZmkH55Cn
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一下代码重构了。 ^Nds@MR{8'
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我把原本我的做法也提供出来供大家讨论吧: 4Wvefq"
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首先,为了实现分页查询,我封装了一个Page类: [_ uT+q3
java代码: GbQg(%2F
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/*Created on 2005-4-14*/ x1Z'_Qw
package org.flyware.util.page; pI.8Ip_r
u^i3 @JuX
/** .qf~t/o
* @author Joa 4\ElMb[]
* .=yv m
*/ n``9H91
publicclass Page { #RyTa
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/** imply if the page has previous page */ 2[1t
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privateboolean hasPrePage; ]
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u^Ktz
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/** imply if the page has next page */ WAtv4
privateboolean hasNextPage; p<mBC2!%
{wk#n.c
/** the number of every page */ owyQFk
privateint everyPage; lqO>Q1_{K
A@Zqh<,Ud
/** the total page number */ M+j*5wNy
privateint totalPage; WuI$
A5\ Hq
/** the number of current page */ n
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privateint currentPage; MO| Dwuaf
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/** the begin index of the records by the current _KT'W!7
F|'u0JQ)$
query */ )_>'D4l?
privateint beginIndex; {:\LFB_
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/** The default constructor */ {61Y;
public Page(){ 8}AWU
:AQ9-&i/a-
} 3 _!MVT
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/** construct the page by everyPage o9C#5%9
* @param everyPage +M#}(hK
* */ A@:U|)+4
public Page(int everyPage){ Nq6;
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this.everyPage = everyPage; !&.-{ _$
} i6P$>8jBQ-
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/** The whole constructor */ Q Wc^}#!!
public Page(boolean hasPrePage, boolean hasNextPage, $-jj%kS
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+7AH|v8
int everyPage, int totalPage, CY*GCkH
int currentPage, int beginIndex){ i{:iRUC#
this.hasPrePage = hasPrePage; cF EO}
this.hasNextPage = hasNextPage; 4#:Eq=(W
this.everyPage = everyPage; Jk7 Am-.0
this.totalPage = totalPage; MZWv#;.]
this.currentPage = currentPage; 8^_e>q*W
this.beginIndex = beginIndex; fz8 41 <Y
} B~@Gfb>`'
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/** [~G1Rz\h
* @return ,)TnIByM
* Returns the beginIndex. yh|+Usa
*/ XIdC1%pr;
publicint getBeginIndex(){ Bu?Qyz2O
return beginIndex; vSv1FZu*
} 1{a4zGE?[
E`C!q
X>
/** Tdz#,]Q
* @param beginIndex KDV.ZSF7
* The beginIndex to set. tGbx/$Y
*/ voTP,R[}85
publicvoid setBeginIndex(int beginIndex){ [f[Wz{Q#Y
this.beginIndex = beginIndex; M"qS#*{
} rce._w }
}s6Veosl
/** B(} 'yY@%u
* @return e"{"g[b/7
* Returns the currentPage. {^:NII]
*/ EQw7(r|v:
publicint getCurrentPage(){ Di}M\!-[
return currentPage; F?cwIE\J
} =*zde0T?l
Rh$+9w
/** y7rT[f/J
* @param currentPage s aHY9{)
* The currentPage to set. p&)d]oV>
*/ kd]CV7(7
publicvoid setCurrentPage(int currentPage){ EgbH{)u
this.currentPage = currentPage; FgrVXb_q
} Je2&7uR0
XJy.xI>;
/** 0_Elxc
* @return /iAhGY
* Returns the everyPage. $e,r>tgD
*/ gSj0+|
publicint getEveryPage(){ B%kC>J
return everyPage; `
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} AGjjhbGB
>ZeARCf"f
/** E $W0HZ'
* @param everyPage .)p%|A#^
* The everyPage to set. -AolW+Y
*/ y9LO;{(
publicvoid setEveryPage(int everyPage){ M&gi$Qs[E
this.everyPage = everyPage; /eXiWa sQ
} WSv%Rxr8L
$;~YgOVZ5
/** P|p
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* @return MA}}w&
* Returns the hasNextPage. >LN*3&W
*/ ._<,
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publicboolean getHasNextPage(){ +uTl
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return hasNextPage; ![fNlG!r
} #Ak|p#7 ^
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/** ~Eb:AC5
* @param hasNextPage v<<ATs%w
* The hasNextPage to set. Dsc0;7~6
*/ njO~^Hl7
publicvoid setHasNextPage(boolean hasNextPage){ G!G:YVWXP
this.hasNextPage = hasNextPage; :2/jI:L~
} .}Ys+d1b9c
E`hR(UL
?
/** H Vhd#Q;
* @return UugR
* Returns the hasPrePage. K=}Eupn=
*/ v&d'ABeT
publicboolean getHasPrePage(){ 2mMi=pv9
return hasPrePage; ,=c(P9}^
} Q>9bKP
%X}vuE[[UC
/** j8PeO&n>
* @param hasPrePage !>=lah$&
* The hasPrePage to set. U /~uu
*/ q8;MPXSG3
publicvoid setHasPrePage(boolean hasPrePage){ 4`fV_H.8
this.hasPrePage = hasPrePage; k'PvQl"I
} a^E>LJL
Sl'$w4s
/** ~-uf%=
* @return Returns the totalPage. ^6F, lS _t
* z 0zB&}
*/ Gm9
publicint getTotalPage(){ I|>.&nb
return totalPage; J7aYi]vI
} /me ]sOkn
@p}_"BHYWt
/** %hw4IcWJ|
* @param totalPage KIR3m
)
* The totalPage to set. LpSF*xm
*/ 2QEH!)lvr
publicvoid setTotalPage(int totalPage){ |%fNLUJ)
this.totalPage = totalPage; *A8Et5HAv
} l{ql'm
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} .a(G=fk
}$qrNbLJ
skTaIGRL
t%5bDdo
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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 OI78wG
j!oX\Y-: &
个PageUtil,负责对Page对象进行构造: /FpPf[
java代码: m\/) m]wR
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/*Created on 2005-4-14*/ v.vkQQ0[9
package org.flyware.util.page; IMMsOl
xfC$u`e=
import org.apache.commons.logging.Log; >.9V`m|
import org.apache.commons.logging.LogFactory; &V SZ
Kb;Pd!Q
/** wgolgof
* @author Joa {hN<Ot
* !7Qj8YmS
*/ I|K!hQ"m
publicclass PageUtil { :oC;.u<*8
*8;<w~
privatestaticfinal Log logger = LogFactory.getLog ' S,g3
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(PageUtil.class); %[9ty`UE
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/** lcy+2)+
* Use the origin page to create a new page qwnVtD
* @param page J kAd3ls
* @param totalRecords 9^N(s7s
* @return s|c}9/Xe)
*/ OpU9:^r
publicstatic Page createPage(Page page, int s'l|Ii
\w1',"l`
totalRecords){ w^ofH-R/
return createPage(page.getEveryPage(), aaN/HE_
.3n\~Sn
page.getCurrentPage(), totalRecords); nnE'zk<"
} t0v>J9
7r)]9_[(
/** !O}e)t
* the basic page utils not including exception 9%3+\[s1
c9Cc%EK
handler xx7&y!_
* @param everyPage k $8Zg*)
* @param currentPage NG:4Q.G1g
* @param totalRecords @OUBo;/
* @return page JdUdl_Dz
*/ OT=1doDp
publicstatic Page createPage(int everyPage, int ?MmQ'1N
6GVAR
currentPage, int totalRecords){ @2d9
7.X
everyPage = getEveryPage(everyPage); M.Tp)ig\#
currentPage = getCurrentPage(currentPage); DTo"{!
int beginIndex = getBeginIndex(everyPage, "$K]+0ryG<
Z1+Ewq3m
currentPage); O{7#Xj
:_
int totalPage = getTotalPage(everyPage, 3vAP&i'I
<gH-`3J6
totalRecords); 0pW;H|h
boolean hasNextPage = hasNextPage(currentPage, hu"-dT;4]
0`p"7!r
totalPage); !
9*l!(
boolean hasPrePage = hasPrePage(currentPage); (4yXr|to}
d7QUg6=
returnnew Page(hasPrePage, hasNextPage, +t&)Z
everyPage, totalPage, ;V?(j3b[
currentPage, 0.nkh6?
!Y7$cU &
beginIndex); y!R9)=/M
} |JWYsqJ0U
n
c~JAT#'
privatestaticint getEveryPage(int everyPage){ 0c!^=(
return everyPage == 0 ? 10 : everyPage; zw$\d1-+h
} KU0Ad);e
ePv`R'#
privatestaticint getCurrentPage(int currentPage){
(V'w5&f(L
return currentPage == 0 ? 1 : currentPage; WS.g`%
} P_8!Gp
Z02EE-A
privatestaticint getBeginIndex(int everyPage, int xw_$1
S
SK@ p0:
currentPage){ }2m>S6""A
return(currentPage - 1) * everyPage; TqV^\C?
} $dK430_B
0]MD?6-
privatestaticint getTotalPage(int everyPage, int L ed{#+
`/N={
totalRecords){ t:P]bp^#
int totalPage = 0; %{:pBt:Z
h<$%y(lP
if(totalRecords % everyPage == 0) N`fFYO
totalPage = totalRecords / everyPage; v.TgB)
else +|pYu<OY
totalPage = totalRecords / everyPage + 1 ; gae=+@z
5T( cy
return totalPage; 7,Z<PE
} ZHeq)5C ;f
ycOnPTh
privatestaticboolean hasPrePage(int currentPage){ #<sK3 PT
return currentPage == 1 ? false : true; !T
,=kh
} @.}Y'`9L
/%p
~
privatestaticboolean hasNextPage(int currentPage, _zzNF93Bn
!?+0O]`}
int totalPage){ Xc"
%-
return currentPage == totalPage || totalPage == =OPX9oG
! os@G
0 ? false : true; Cd]A1<6s
} a&)!zhVP
gE=9K @
wS&D-!8v
} KECW~e`
di9OQ*6a7
^u"WWLZ
0nB[Udk?
FyPG5-
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。 qIQ
61><
VQG$$McJ
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 .Z"`:4O
/4;A.r`;
做法如下: I2SH
j6-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o&z [d
DS7L}]
的信息,和一个结果集List: em )%U
java代码: )flm3G2u
\awkt!Wa
-Q?c'e
/*Created on 2005-6-13*/ 0a<h,s0"2
package com.adt.bo; 8tna<Hx
/7p(%vr
import java.util.List; 41+WIa
L
l`:u5\ rM
import org.flyware.util.page.Page; 1ZYo-a;)
afD {w*[8
/** p>3QW3<
* @author Joa a;-%C{S9r
*/ I\c7V~^hnG
publicclass Result { ONy\/lu|
E.ji;5
private Page page; &N6[*7
Y}t)!}p$r
private List content; XIZN9/;
Jmg9|g!f
/** BYhiP/^
* The default constructor 2 @T~VRy
*/ R2C~.d_TDu
public Result(){ {[Y7h}7
super(); jrz.n4Y`
} 'wMvO{}$
$o\z4_I
/** y&O?`"Uv/M
* The constructor using fields .oTS7rYw
* t)?K@{ 9
* @param page Y`4 LMK[]
* @param content J=: \b
*/ Q^3{L\6_
public Result(Page page, List content){ S&XlMu
this.page = page; 6\I1J=
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this.content = content; 6J}Yr5oD
} &.s.g\
mXS]SE
/** 6oZHSjC*
* @return Returns the content. ]o0]i<:
*/ WvfM.D!
publicList getContent(){ g"kI1^[nj
return content; UpE+WzY
} }' Y)"8AIA
v'Ehr**]+
/** 6~2upy~e
* @return Returns the page. *mJ#|3I<
*/ = _N[mR^
public Page getPage(){ J` gG`?
return page; V rx,'/IS8
} (y&sUc9
B9$f y).Gp
/** 'kY/=*=Q
* @param content /
j%~#@
* The content to set. TecMQ0
KD
*/ |mRlP5
public void setContent(List content){ |j9aTv[`
this.content = content; -\;0gnf{J
} t0@AfO.'1
Jp}\@T.
/** 5p:BHw;%;
* @param page IpSWg
* The page to set. YwF&-~mp7n
*/ yZ)9Hd
publicvoid setPage(Page page){ lz<'
L.
.
this.page = page; Ev7v,7`z
} uPr!;'J=
} G `!A#As
b6Z3(!]
]
eiyr^Sch.
GI,TE
WG\
_eRj
2. 编写业务逻辑接口,并实现它(UserManager, oA7DhU5n
2@
9? ~?r
UserManagerImpl) G/(,,T}eG
java代码: <DR!AR)
_Y]Oloo('
Cojs;`3iF:
/*Created on 2005-7-15*/ t^zE^:06
package com.adt.service; :3
Hz!iZM
tvFe_*Ck
import net.sf.hibernate.HibernateException; d4^x,hzV
=7H\llL4BC
import org.flyware.util.page.Page; _&9P&Zf4
[TUs^%2@
import com.adt.bo.Result; 7qUg~GJX
rTVv6:L
/** ZN;ondp4
* @author Joa ISFNP&&K
*/ 3BD&;.<r
publicinterface UserManager { [r3sk24
Eri007? D
public Result listUser(Page page)throws $%"hhju
An0N'yo"Z
HibernateException; '\op$t/
w2X HY>6];
} z[<Na3]
Bt,'g*Cs
s5mJ
-
RN[x\" ,
lMu-,Z="
java代码: ,tg]Gt
$MwBt
\<T7EV.
/*Created on 2005-7-15*/ H?Q--pG8
package com.adt.service.impl; hE`d@
!z4I-a
import java.util.List; sZr \mQ~
zx2`0%Q
import net.sf.hibernate.HibernateException; K\;4;6g
7.ein:M|CB
import org.flyware.util.page.Page; V59!}kel1%
import org.flyware.util.page.PageUtil; Db*b"/]
U!c+i#:t
import com.adt.bo.Result; A- Abj'
import com.adt.dao.UserDAO; R13k2jLSQ
import com.adt.exception.ObjectNotFoundException; JeNX5bXW
import com.adt.service.UserManager; /}6y\3h
wL3RcXW``e
/** G/#<d-}_
* @author Joa [f lK
*/ =P9rOK=
publicclass UserManagerImpl implements UserManager { k\T]*A
8,[ *BgeX
private UserDAO userDAO; JU5,\3Lz#
\ctzv``/n
/** XXA'B{@Y)
* @param userDAO The userDAO to set. aZ\Z7(
*/ ^w``(-[*
publicvoid setUserDAO(UserDAO userDAO){ >#;;g2UV
this.userDAO = userDAO; WTl0}wi
} cQThpgha
O{\<Izm`D
/* (non-Javadoc) VBDb K|
* @see com.adt.service.UserManager#listUser <D)@;A
o&@ y^<UQ
(org.flyware.util.page.Page) <bg6k . s
*/ c U(z5th
public Result listUser(Page page)throws &K9RV4M5
u1u;aG
HibernateException, ObjectNotFoundException { q5EkAh<PD|
int totalRecords = userDAO.getUserCount(); SnXM`v,
if(totalRecords == 0) I{U|'a
throw new ObjectNotFoundException ts@$*
8,RqhT)2#
("userNotExist"); Ax~
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page = PageUtil.createPage(page, totalRecords); 0]'
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List users = userDAO.getUserByPage(page); 8$47Y2r@
returnnew Result(page, users); N: 38N
} MMET^SO
a`^$xOK,
} Nv;'Ys P
W1xPK*
J>#yA0QD2
c?c\6*O
_4SZ9yu
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 # .(f7~
u^E0u^
询,接下来编写UserDAO的代码: ELMz~vp
3. UserDAO 和 UserDAOImpl: d#bg(y\G|
java代码: %P<fz1
h,BPf5\S
$t"QLsk0
/*Created on 2005-7-15*/ +N+117m
package com.adt.dao; *& );-r`.
Sw-2vnSdM
import java.util.List; Z>Rshtg
%Y'/_
esH2
import org.flyware.util.page.Page; q8/k$5E
[kr-gV
import net.sf.hibernate.HibernateException; r^rk@W;[
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/** h]z 8.k2n
* @author Joa ZTfW_0
*/ b 1Wz
publicinterface UserDAO extends BaseDAO { []
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+
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publicList getUserByName(String name)throws _1$ Y\Y
yW7>5r
HibernateException; rZ-< Ryg
1)ij*L8k
publicint getUserCount()throws HibernateException; tlvZy+Blv
E2cZk6~m{
publicList getUserByPage(Page page)throws ZK'WKC
4s_5>r4
HibernateException; [`tNa Vg
CA&VnO{r
} $/#[,1
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S8
zlQBBm;fE
"o u{bKe
Lp|n)29+du
java代码: y,n.(?!*
xpuTh"ED
eA?|X|
/*Created on 2005-7-15*/ T7/DH
package com.adt.dao.impl; $;=?[Cn
x]%,?Vd?
import java.util.List; Gkfzb>_V]
~/aCzx~
import org.flyware.util.page.Page; Oz]$zRu/0
+CSR!
import net.sf.hibernate.HibernateException; M($GZ~ b%A
import net.sf.hibernate.Query; v6uRzFw
HEa7!h[a'
import com.adt.dao.UserDAO; zYdieE\-
&%/T4$'+Y+
/** Q\xDAOEL
* @author Joa G
OG[^T
*/ 3bo
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public class UserDAOImpl extends BaseDAOHibernateImpl eUR+j?5I
N;!!*3a9=
implements UserDAO { 8$iHd
/#eS3`48
/* (non-Javadoc) ObreDv^,
* @see com.adt.dao.UserDAO#getUserByName
gy|o#&e]%
I*cb\eU8Y
(java.lang.String) ]uh/ !\
*/ 3N2d@R
publicList getUserByName(String name)throws DOkuT/+
BAi0w{
HibernateException { w6mYLK%
String querySentence = "FROM user in class ZzR0k
y[S9b(:+
com.adt.po.User WHERE user.name=:name"; ^vxNS[C`;
Query query = getSession().createQuery e(b$LUV
r6aIW8
(querySentence); 2*
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query.setParameter("name", name); D88IU9V&n
return query.list(); r[7*1'.p
} ,->5 sJ{U
5^ubXA
/* (non-Javadoc) 3tkCmB
* @see com.adt.dao.UserDAO#getUserCount() f;,*P,K
*/ 0blbf@XA
publicint getUserCount()throws HibernateException { [fvjvN`
int count = 0; r5(efTgAd+
String querySentence = "SELECT count(*) FROM Q4]Od{[
N$:-q'hX
user in class com.adt.po.User"; JlRNJ#h>
Query query = getSession().createQuery WI&}94w
Y;g\ @j
(querySentence); =kK%,Mr
count = ((Integer)query.iterate().next '`W6U]7>
dShGIH?
()).intValue(); 8$X3 J[_j
return count; /?TR_>
} ;AL:VU
@g" vuaG}
/* (non-Javadoc) {/aHZ<I&^h
* @see com.adt.dao.UserDAO#getUserByPage `Nz`5}8.?
.XkVdaX
(org.flyware.util.page.Page) 4mX?PKvbn
*/ I};*O6D`
publicList getUserByPage(Page page)throws QJjk#*?,|
"d}ey=$h4
HibernateException { Co=Bq{GY
String querySentence = "FROM user in class u'DpZ
8=0I4\
com.adt.po.User"; :LdPqFXj
Query query = getSession().createQuery EUV8H}d5
&=:3/;c
(querySentence); ZYt <O
query.setFirstResult(page.getBeginIndex()) gMPp'^g]_
.setMaxResults(page.getEveryPage()); G)Y,*.,
return query.list(); uAoZ&8D6
} @^g~F&Ta
H ="I=}
} D$NpyF.87
X2:23j<
WlGT&m&2
d 79 2#Dc
91q
至此,一个完整的分页程序完成。前台的只需要调用 HGd.meQ
0plX"NU
userManager.listUser(page)即可得到一个Page对象和结果集对象 F>X<=YO0
pe3;pRh'
的综合体,而传入的参数page对象则可以由前台传入,如果用 ),xD5~_=q
Y
ZuA"l Y
webwork,甚至可以直接在配置文件中指定。 N|Xm{@C
H5:f&m
下面给出一个webwork调用示例: k6o8'6wN
java代码: SQx&4R.
Ve)BF1YG
z%lJWvaA7
/*Created on 2005-6-17*/ 2\T\p<_20
package com.adt.action.user; 9zIqSjos"
)1HWD]>4
import java.util.List; WNQ<XBqAw
kl9~obX
1
import org.apache.commons.logging.Log; A&WC})H5
import org.apache.commons.logging.LogFactory; `c-omNu
import org.flyware.util.page.Page; 'ShK7j$
\[*q~95$v
import com.adt.bo.Result; ev_' .t'
import com.adt.service.UserService; Q[|*P ] w
import com.opensymphony.xwork.Action; H3ovF
$p$p C/:%
/** iJmzVR+
* @author Joa fz2}M:u
*/ 8gt&*;'}*D
publicclass ListUser implementsAction{ ~mi4V
wQ@:0GJH
privatestaticfinal Log logger = LogFactory.getLog #reW)P>
|')PQ
(ListUser.class); 6h %rt]g
wp>
z04
private UserService userService; ~<_WYSzS
YgS,5::SU
private Page page; e+{lf*"3
;ny 9q
privateList users; B<,7!:.II
kOq8zYU|
/* n5^57[(
* (non-Javadoc) ~<s =yjTu+
* oDi+\0
* @see com.opensymphony.xwork.Action#execute() Qh-:P`CN
*/ WY!4^<|w"
publicString execute()throwsException{ f#w
u~*c
Result result = userService.listUser(page); 1KBGML-K3
page = result.getPage(); S9r+Nsn
users = result.getContent(); (+/d*4
return SUCCESS; NuD|%Ebs
} MxKTKBxQ
]yZ%wU9!
/** RgQs`aI
* @return Returns the page. _:p-\Oo.
*/ J.M&Vj:
public Page getPage(){ s;*
UP
return page; -V[x
q
} 5/7(>ivn
mw;4/
/R
/** (}.MB3`#C
* @return Returns the users. W g6H~x
*/ 8"ZS|^#
publicList getUsers(){ SPt/$uYJ
return users; |g!d[ct]
} ^m&P0
u#Jr_ze
/** 32%Fdz1S
* @param page ?h%Jb^#9
* The page to set. ctjQBWE
*/ &vn2u bauS
publicvoid setPage(Page page){ ar}-~~h 5
this.page = page; >8=lX`9f{
} 0.w7S6v|&
UOl*wvy
/** n_9Ex&?e
* @param users 72yJv=G
* The users to set. A~<!@`NjB
*/ [(5.?
publicvoid setUsers(List users){ `&