Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 (3"N~\9m
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1<Sg@
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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 RA!q)/+
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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 8t3m$<7
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分页支持类: !E_Zh*lgm
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java代码: `BQv;NtP
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package com.javaeye.common.util; "M, 1ElQ
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import java.util.List; .faf!3d
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publicclass PaginationSupport { N+ak{3
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; 2E?!Q I\O
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privateList items; a}uYv:
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privateint totalCount; (Vr%4Z8
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privateint[] indexes = newint[0]; 4EHrd;|
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privateint startIndex = 0; <sw@P":F
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public PaginationSupport(List items, int +U1
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totalCount){ hbOXR.0z
setPageSize(PAGESIZE); tEL9hZzI
setTotalCount(totalCount); veHe
setItems(items); p]%di8&;N
setStartIndex(0); =C2sl;7~*
} K Ax=C}9
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public PaginationSupport(List items, int )Xh}N
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totalCount, int startIndex){ -?-XO<I
setPageSize(PAGESIZE); h7E~I
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setTotalCount(totalCount); g_1#if&
setItems(items); fO$){(]^
setStartIndex(startIndex); dYwkP^KB
} v,S5C
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public PaginationSupport(List items, int p_h/hTi
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totalCount, int pageSize, int startIndex){ |)+
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setPageSize(pageSize); Bz<hP*.O
setTotalCount(totalCount); $8)XN-%(
setItems(items); P&uSh?[ ^
setStartIndex(startIndex); )-26(aNGT
} Rh ^(91d
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publicList getItems(){ gLB(A\yG
return items; |ZL?Pqki
} {2h*NFp
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publicvoid setItems(List items){ \ dFE.4
this.items = items; 0k5-S~_\
} oGRk/@
=nGFLH6)
publicint getPageSize(){ %+H _V1F
return pageSize; 3l~+VBR_
} l cie6'<
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publicvoid setPageSize(int pageSize){ D xV=S0P
this.pageSize = pageSize; ${MzOi
} x-m*p^}
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publicint getTotalCount(){ SHX`/
return totalCount; ~= *o
} 3uocAmY
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publicvoid setTotalCount(int totalCount){ s`jlE|jtN
if(totalCount > 0){ F(yR\)!C
this.totalCount = totalCount; 68XJ`/d
int count = totalCount /
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pageSize; }6@E3z]AMO
if(totalCount % pageSize > 0) hBjU(}\3
count++; 6u0>3-[6OD
indexes = newint[count]; } Bf@69
for(int i = 0; i < count; i++){ az F!V
indexes = pageSize * #4JMb#q0E
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} rO7_K>g?
}else{ u%~'+=
this.totalCount = 0; )2Ei<
} hOwb
} `(FjOd
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publicint[] getIndexes(){ C2}y#A I
return indexes; v>]g="5}8
} @G"nkB
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publicvoid setIndexes(int[] indexes){ bzFac5n)Q
this.indexes = indexes; _y~6b{T
} L5bq\
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publicint getStartIndex(){ FJc8g6M
return startIndex; x/DV> Nfn
} +]eG=.
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publicvoid setStartIndex(int startIndex){ Voo'ZeZa
if(totalCount <= 0) nQ\` ]_C
this.startIndex = 0; E7L>5z
elseif(startIndex >= totalCount) \>6*U r
this.startIndex = indexes ,)1C"'
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[indexes.length - 1]; {Dpsr` &
elseif(startIndex < 0) ',r` )9o
this.startIndex = 0; LP"g(D2'n
else{
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this.startIndex = indexes b* n3Fej
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[startIndex / pageSize]; 4Hz3KKu
} 4
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} C}h(WOcr`X
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publicint getNextIndex(){ z}[u~P,
int nextIndex = getStartIndex() + < o?ua}
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pageSize; uppa`addK
if(nextIndex >= totalCount) HPt3WBRzS;
return getStartIndex(); z\m$>C|
else U4"^NLAq
return nextIndex; |8'}mjs.Q
} ~^2w)-N
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publicint getPreviousIndex(){ rr
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int previousIndex = getStartIndex() - k* C69
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pageSize; 4;6"I2;zfG
if(previousIndex < 0) =3035{\
return0; sWlxt q g
else )Z:-qH
return previousIndex; T \/^4N`
} nX!%9x$3
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} 4mDHAR%D
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抽象业务类 (2;Aqx5i
java代码: mfj{_fR3
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/**
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* Created on 2005-7-12 =78y*`L
*/ .4a|^ vT
package com.javaeye.common.business; jA,y.(mR
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import java.io.Serializable; r ~{nlLO}
import java.util.List; "q?(rx;
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import org.hibernate.Criteria; ^VYR}1Mw
import org.hibernate.HibernateException; cIO/8D#zU
import org.hibernate.Session; }@bp v
import org.hibernate.criterion.DetachedCriteria; %g7j7$c
import org.hibernate.criterion.Projections; 16Qu{K
import )j8'6tk)Z
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org.springframework.orm.hibernate3.HibernateCallback; Zna6-0o
import ~;HASHu
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org.springframework.orm.hibernate3.support.HibernateDaoS {Vu=qNx
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upport; C/!P&`<6
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import com.javaeye.common.util.PaginationSupport; \l=A2i7TQ
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public abstract class AbstractManager extends t 9(,JC0
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HibernateDaoSupport { D!* SA
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privateboolean cacheQueries = false; QO$18MBcc
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privateString queryCacheRegion; ^h_rE
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publicvoid setCacheQueries(boolean Zdrniae
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cacheQueries){ 0Y0z7A:
this.cacheQueries = cacheQueries; IYe[IHny1
} &DQ_qOKD
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publicvoid setQueryCacheRegion(String rv{ Wti[
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queryCacheRegion){ -n@,r%`UK
this.queryCacheRegion = .\`MoH
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queryCacheRegion; BHpay
} &4wSX{c/P
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publicvoid save(finalObject entity){ "U9e)a0v
getHibernateTemplate().save(entity); ~e|E5[-i
} <YCjo[(~
*=md!^x`
publicvoid persist(finalObject entity){ xz`0V}dPl
getHibernateTemplate().save(entity); =8vwaJ
} O4nA?bA
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publicvoid update(finalObject entity){ D8k >f ]
getHibernateTemplate().update(entity); uaD+G:{[
} aAcQmq TT
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publicvoid delete(finalObject entity){ UChLWf|'
getHibernateTemplate().delete(entity); *r4FOA%P
} >]B_+r0m^
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publicObject load(finalClass entity, 7yG%E
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finalSerializable id){ hB'rkjt
return getHibernateTemplate().load k'v+/6 Y
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(entity, id); ^!m%:r7Dr
} l(MjLXw5
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publicObject get(finalClass entity, D!,'}G#
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finalSerializable id){ de8xl
return getHibernateTemplate().get >8NUji2I
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(entity, id); v?d`fd
} 9QD+
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publicList findAll(finalClass entity){ G_WFg$7G%
return getHibernateTemplate().find("from 1 )u,%
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" + entity.getName()); lE+Duap:
} U8aNL
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publicList findByNamedQuery(finalString &w=ul'R98
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namedQuery){ WM9({BZ
return getHibernateTemplate ;<MHl[jJD
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().findByNamedQuery(namedQuery); Ga^:y=m
} "6~+-_:
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publicList findByNamedQuery(finalString query, ]:#W$9,WL
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finalObject parameter){ tPk>hzW
return getHibernateTemplate *>GRU8_}
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().findByNamedQuery(query, parameter); B<|Vm.D
} 5IgO4 <B
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publicList findByNamedQuery(finalString query, TCgW^iu
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finalObject[] parameters){ ,7d#t4
return getHibernateTemplate 7OPRf9+o
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().findByNamedQuery(query, parameters); xNJ*TA[+
} nh+h3"-d
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publicList find(finalString query){ ~1Ffu x
return getHibernateTemplate().find ZlMS=<hgFx
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(query); p`"Ic2xPJ
} uowdzJ7
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publicList find(finalString query, finalObject 1Si$Q
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parameter){ aMK\&yZD
return getHibernateTemplate().find z2A,*|I
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(query, parameter); Ln4Dq[M
} kK&AK2
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public PaginationSupport findPageByCriteria i\>?b)a>
^= kr`5
(final DetachedCriteria detachedCriteria){ '~{kR=+
return findPageByCriteria 2/))Y\~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); R<r,&X?m
} Fbw.Y6
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public PaginationSupport findPageByCriteria fndH]Yp
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(final DetachedCriteria detachedCriteria, finalint \Jwc[R&x
Co/04F.
startIndex){ 7 $dibTER
return findPageByCriteria b.
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(detachedCriteria, PaginationSupport.PAGESIZE, 4`sW_
ks
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startIndex); IR8qFWDZ
} 2%-/}'G*
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public PaginationSupport findPageByCriteria F:Yp1Wrb <
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(final DetachedCriteria detachedCriteria, finalint Gg^gK*D
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pageSize, R$2\Xl@qQF
finalint startIndex){ i66/2BUh.
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ C)cuy7<
publicObject doInHibernate i2)$%M&
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(Session session)throws HibernateException { L7yEgYB
Criteria criteria = F~GIfJU
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detachedCriteria.getExecutableCriteria(session); *b`1+~p_2
int totalCount = &<(&u`S
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((Integer) criteria.setProjection(Projections.rowCount !#4b#l(e6
1#XZVp;M
()).uniqueResult()).intValue(); CSzu$Hnq
criteria.setProjection j9f Q V
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(null); WXa<(\S\V
List items = A4)TJY
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criteria.setFirstResult(startIndex).setMaxResults /vLW{ %
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(pageSize).list(); @n$/2y_.
PaginationSupport ps = 2t3)$\ylQp
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new PaginationSupport(items, totalCount, pageSize, 0>3Sn\gZ(
F ^)(
7}ph
startIndex); -{p~sRc&
return ps; 5[`f(;
}
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}, true); e'3y^Vg
} K{iC'^wP
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public List findAllByCriteria(final O~5*X f
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DetachedCriteria detachedCriteria){ *3(mNpi{_
return(List) getHibernateTemplate T?*f}J
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().execute(new HibernateCallback(){ xQxq33\
publicObject doInHibernate mfk^t`w_
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(Session session)throws HibernateException { V+$fh2t
Criteria criteria = ._6Q "JAB
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detachedCriteria.getExecutableCriteria(session); =AX"'q
return criteria.list(); j^m pkv<P
} H6MG5f_
}, true); GjX6noqT
} cJ'OqV F
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public int getCountByCriteria(final @lCyH(c%
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DetachedCriteria detachedCriteria){ 9bUFxSH
Integer count = (Integer) +6(\7?
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getHibernateTemplate().execute(new HibernateCallback(){ ufocj1IU
publicObject doInHibernate 4V'HPD>=V
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(Session session)throws HibernateException { E_#?;l>
Criteria criteria = rs0Wy
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detachedCriteria.getExecutableCriteria(session); RVh{wg
return Lwo9s)j<e
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criteria.setProjection(Projections.rowCount Oh,]"(+
+?6@%mW'
()).uniqueResult(); Bk/&H-NI
} Fzy5k?R
}, true); q!YAA\'31
return count.intValue(); Fm[3Btn
} wT +\:y
} rw[Ioyr-
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用户在web层构造查询条件detachedCriteria,和可选的 IJD E{)
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 &W*^&0AV
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PaginationSupport的实例ps。 @el
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ps.getItems()得到已分页好的结果集 EvF[h:C2
ps.getIndexes()得到分页索引的数组 6>z,7 [
ps.getTotalCount()得到总结果数 /Edq[5Ah
ps.getStartIndex()当前分页索引 0@Z}.k30
ps.getNextIndex()下一页索引 Yzw[.(jc}
ps.getPreviousIndex()上一页索引 JgBC:t^\pV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 TrBW0Bn>p
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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 [gj>ey8T
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一下代码重构了。 LX#gc.c
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我把原本我的做法也提供出来供大家讨论吧: \85~~v@
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首先,为了实现分页查询,我封装了一个Page类: /|isRh|
java代码: \J(kM,ZJ
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/*Created on 2005-4-14*/ BO.Db``
package org.flyware.util.page; q`UaJ_7
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/** ~EU\\;1Rmq
* @author Joa WWATG=
* S q{@4F}d
*/ -_XTy!I
publicclass Page { /y(0GP4A
q}W})
/** imply if the page has previous page */ )W&{OMr
privateboolean hasPrePage; W:K '2j
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/** imply if the page has next page */ fg4mP_
privateboolean hasNextPage; U*?`tdXJ$
/*MioaQB}p
/** the number of every page */ ]'pL*&"X
privateint everyPage; M~~)tJYsu
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/** the total page number */
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privateint totalPage; bAwKmk9C
egVKAR-
/** the number of current page */ 4issj$
privateint currentPage; 8e1Z:axn0
}_5 R9w]"
/** the begin index of the records by the current Udq!YXE0
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query */ x,ZF+vE
privateint beginIndex; h}kJ,n
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/** The default constructor */ $lq.*UQ;0
public Page(){ SmIcqM
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} +}PN+:yV
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/** construct the page by everyPage @_1cY#!
* @param everyPage m.<u!MI
* */ Qxk & J
public Page(int everyPage){ o4wSt6gBcJ
this.everyPage = everyPage; jcb&h@T8kv
} |gIE$rt-~W
5{bc&?"
/** The whole constructor */ O8SE)R~
public Page(boolean hasPrePage, boolean hasNextPage, _
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SZ}=~yoD(
v*%52_
int everyPage, int totalPage, ESYF4-d+
int currentPage, int beginIndex){ V@[C=K
this.hasPrePage = hasPrePage; {Wu[e,p
this.hasNextPage = hasNextPage; n4y]h
this.everyPage = everyPage; fP\q?X@]E
this.totalPage = totalPage; 8KYI Hw
this.currentPage = currentPage; 8QoxU"
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this.beginIndex = beginIndex; x0WinLQ
} gY8$Rk
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/** ~clX2U8u`
* @return Rc
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* Returns the beginIndex. C511hbF
*/ aYDo0?kF'
publicint getBeginIndex(){ t"Ah]sD
return beginIndex; c+
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} AV7#,+p%G
cqSXX++CS,
/** _{-[1-lN5_
* @param beginIndex dDIR~!T
* The beginIndex to set. gu+zfvkcY
*/
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publicvoid setBeginIndex(int beginIndex){ o]RZd--c<
this.beginIndex = beginIndex; b $JS|
} @Z2np{X:
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/** Od)y4nr3~
* @return gdA2u;q
* Returns the currentPage. =/`]lY&
*/ oeB'{bG
publicint getCurrentPage(){ Fxc_s/^=t
return currentPage; O^j*"#f
} &K{8-
t
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/** J=t}9.H~=
* @param currentPage }ML2-k
* The currentPage to set. &lLfVa-l
*/ U||GeEd
publicvoid setCurrentPage(int currentPage){ `;J`O02
this.currentPage = currentPage; c!/+0[
} X6r0+D5AvB
!ltq@8#_|
/** fBj)HoHQW
* @return >36,lNt
* Returns the everyPage. X;N?L%Pp
*/ 6-fv<Pn
publicint getEveryPage(){ R$8{f:Pj
return everyPage; yDwh]t
} WFh.oe8
(D) KU9B>
/** $`55 E(
* @param everyPage _p*8ke
* The everyPage to set. 6{Q-]LOc[.
*/ [&PF ;)i
publicvoid setEveryPage(int everyPage){ kM{8zpn
this.everyPage = everyPage; bXOKC
} Rd5_{F
66,(yxg
/** fg3Jv*
* @return c|;n)as9(%
* Returns the hasNextPage. oV0T
*/ 9K/EteS
publicboolean getHasNextPage(){ 2Y23!hw
return hasNextPage; |w}j!}u
} dN)8r
J\Pb/9M/
/** oDMPYkpTu
* @param hasNextPage XhHgXVVGG<
* The hasNextPage to set. OyF=G^w
*/ R`Z"ey@C
publicvoid setHasNextPage(boolean hasNextPage){ nOvR, 6
this.hasNextPage = hasNextPage; _ERtL5^
} T+ZA"i+
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/** O5 73AA
* @return zMFTkDY
* Returns the hasPrePage. ld@+p
*/ eIY`RMo
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publicboolean getHasPrePage(){ /*T^7Y&
return hasPrePage; "TZY)\{L
} {pIh/0
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/** LhbdvJAk@
* @param hasPrePage Hf?@<4
* The hasPrePage to set. %m\:AK[}
*/ mn?F;=qE
publicvoid setHasPrePage(boolean hasPrePage){ $|- Lw!)D
this.hasPrePage = hasPrePage; m0TV i] v
} f7~dn#<@
'E3T fM
/** 1vj@qw3
* @return Returns the totalPage. 4d5c]%
* aC\f;&P>
*/ -&>V.hi7
publicint getTotalPage(){ Fm0d0j
return totalPage; $G9LaD#;M
} AAlc %d/9
x2"1,1%H7
/** rM,e$
* @param totalPage .iRKuBM/
* The totalPage to set. +ig%_QED[\
*/ Lc{arhN
publicvoid setTotalPage(int totalPage){ @"MYq#2c$
this.totalPage = totalPage; M/=36{,w-
} UpG DLb f^
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} _w4G|j$C
@/.#
/
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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 BqNeY<zB*
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个PageUtil,负责对Page对象进行构造: EVX3uC}{
java代码: ju{Y6XJ)
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/*Created on 2005-4-14*/ GpeW<%
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package org.flyware.util.page; hTX[W%K
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import org.apache.commons.logging.Log; ls^Z"9P
import org.apache.commons.logging.LogFactory; = UH3.
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/** <b zzbR[F
* @author Joa lLTqk\8g
* z!"vez
*/ 4|`>}Nu
publicclass PageUtil { +twoUn{#
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privatestaticfinal Log logger = LogFactory.getLog DO*U7V02
sE% $]Jp
(PageUtil.class); W\~^*ny
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/** qgrJi +WZ
* Use the origin page to create a new page U|}
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* @param page VV$t*9w
* @param totalRecords M,]|L c h
* @return k."p&
*/ \~
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publicstatic Page createPage(Page page, int d&j
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totalRecords){ Jp=fLo 9
return createPage(page.getEveryPage(), F}nwTras
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page.getCurrentPage(), totalRecords); y!#-[K:
} rL{R=0
!{lH*
/** XDemdMy$
* the basic page utils not including exception Z10Vx2B
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handler ' P?h?w^T
* @param everyPage y@3p5o9lv-
* @param currentPage t%lat./yT
* @param totalRecords rm[C{Pn
* @return page >$4#G)s
*/ $d?W1D<A
publicstatic Page createPage(int everyPage, int G\@pg;0|y
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currentPage, int totalRecords){ m-Eh0Zl>Z
everyPage = getEveryPage(everyPage); dz_S6o ]
currentPage = getCurrentPage(currentPage); R*[sO*h\k
int beginIndex = getBeginIndex(everyPage, =fcg4h5(
KxkBP/`3Q
currentPage); yq%5h[M
int totalPage = getTotalPage(everyPage, Za:j;u
Y
gg/`{
totalRecords); ?_NKyiu95
boolean hasNextPage = hasNextPage(currentPage, "h sT^sy
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jS
totalPage); ``-N2U5
boolean hasPrePage = hasPrePage(currentPage); L'= \|r
u:l-qD9=(
returnnew Page(hasPrePage, hasNextPage, entU+O r
everyPage, totalPage, -'&/7e6>y
currentPage, [;u#79aE
MR#*/Iw~
beginIndex); ))"gWO
} 3:+9H}Q
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privatestaticint getEveryPage(int everyPage){ 'C[tPP
return everyPage == 0 ? 10 : everyPage; <u64)8'
} T}#iXgyx
Hb)FeGsd).
privatestaticint getCurrentPage(int currentPage){ w'
7sh5
return currentPage == 0 ? 1 : currentPage; c7e,lgG-
} {X!OK3e
/WuYg
OI
privatestaticint getBeginIndex(int everyPage, int C~ 1]
1R2IlUlzFr
currentPage){ Ir9GgB
return(currentPage - 1) * everyPage; Met]|&
} F$7!j$
Z
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privatestaticint getTotalPage(int everyPage, int 5;a*Xf%V
N,(!
totalRecords){ 8z9{H
int totalPage = 0; n:5M
E*
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if(totalRecords % everyPage == 0) '2(m%X\6
totalPage = totalRecords / everyPage; HlGSt$woX
else +,76|oMsQ%
totalPage = totalRecords / everyPage + 1 ; `b?uQ\#-M
4b;Mb
return totalPage; =oBpS=<7
} KdVKvs[
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privatestaticboolean hasPrePage(int currentPage){ 02-ql
F@i
return currentPage == 1 ? false : true; MEDh
} /F0q8j0
^ ""edCs
privatestaticboolean hasNextPage(int currentPage, I|@+O#
/DQYlNa
int totalPage){ gEh/m.L7
return currentPage == totalPage || totalPage == H1bR+2s
I3t5S;_8
0 ? false : true; #D`@G8~(
} XM$~HG
gmGK3am
$Z]&3VxxY
} :{7+[LcH7
Xg)8}
KkJqqO"EL
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上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 At Wv9
Z
vysLHj
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 a|ufm^F
*6Wiq5M>.
做法如下: (V{/8%mWc
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8Y($ F2
M(-)\~9T
的信息,和一个结果集List: Ca2r<|uA
java代码: LPvp
(1
EZUaYp~M
fQ<sq0'e\
/*Created on 2005-6-13*/ RZa/la*
package com.adt.bo; v3-/ [-XB:
/$~1e7W
import java.util.List; RN$vKJk
,B <\a
import org.flyware.util.page.Page; (5yM%H8:
:/5m
D
/** pjeNBSu6
* @author Joa sZ `Tv[
*/ AxEyXT( h5
publicclass Result { &G{GLP?H
&o:5lxR{
private Page page; [M|^e;tWK
=*\s`ox`
private List content; n
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?@64gdlwq
/** =2R4Z8G
* The default constructor ":]Xr!e
*/ g3^s_*A
public Result(){ 8g#$Y2P
super(); LmrdVSs_
} &.A_d+K&
il0K ^i
/** O. * 0;5
* The constructor using fields (v]%kXy/G
* 3?93Pj3oPt
* @param page 3[m~-8
* @param content R"nB4R0Uh
*/ X~{6$J|]#i
public Result(Page page, List content){ G~9m,l+
this.page = page; ]2AOW}=
this.content = content; @Z5q2Q
} k/K)nH@)
RX gb/VR
/** AWO)]rM
* @return Returns the content. [txOh!sxD
*/ #CS>_qe.{
publicList getContent(){ B,>02EZ
return content; V DFgu
} ^C>kmo3J
!:(+#
/** qGinlE&\
* @return Returns the page. ~D52b1f
*/ P\U<,f
public Page getPage(){ qt8Y3:=8l
return page; ]*0zir/
} [|nK5(e9
E7uIur=g!
/** {##G.n\~
* @param content v?8WQNy
* The content to set. DUOoTlp
*/ g )hEzL0k
public void setContent(List content){ v\xl?F
this.content = content; $>rt0LOF
} mGT('iTM4
U:7h>Z0W
/** +){^HC\7h
* @param page l+ }=D@l
* The page to set. -E-#@s
*/ N_Us6X
publicvoid setPage(Page page){ G]lGoa}]`u
this.page = page; w2LnY1A
} osp~)icun
} k+QGvgP[4@
}">r0v!3
n
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k!c7eP"%8^
~&?([}A
2. 编写业务逻辑接口,并实现它(UserManager, \@Wv{0a(
+t!]nE#
UserManagerImpl) zIa={tU
java代码: h+km? j
}k-V(
axQ>~vWN/
/*Created on 2005-7-15*/ '6N)sqTR
package com.adt.service; bT:u|/I
>8Oa(9 n
import net.sf.hibernate.HibernateException; S_lGrk\j
Fa("Gok[
import org.flyware.util.page.Page; :6Ri% Nb
Ww<Y]H$xZ<
import com.adt.bo.Result; 4D65VgVDM
a%#UF@I
/** Tm%5:/<8
* @author Joa -` ]9o3E7H
*/ kowS| c#
publicinterface UserManager { a;o0#I#Si
)%C.IZ_s2
public Result listUser(Page page)throws 4$-R|@,|_
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HibernateException; gawY{Jr8I
!j!w$
} P1F-Wy1
-}7$;QK&a
dL42)HP5
{"o9pIh{~
%. 1/#{
java代码: v
:pT(0N
1}VaBsEV
yP"2.9\erH
/*Created on 2005-7-15*/ >}SEU-7&\
package com.adt.service.impl; GcO2oq
`KQx#c>'
import java.util.List; jg$qp%7i%
Dk
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import net.sf.hibernate.HibernateException; Ejk;(rxI
/&gg].&2?
import org.flyware.util.page.Page; ^O}a,
import org.flyware.util.page.PageUtil; =2!p>>t,d;
rPk|2l,E,3
import com.adt.bo.Result; }Rh\JDiQ
import com.adt.dao.UserDAO; z5@XFaQ
import com.adt.exception.ObjectNotFoundException; D]~K-[V?l
import com.adt.service.UserManager; rWht},-|1
a`wjZ"}'[
/** 3kxo1eb
* @author Joa Sca"LaW1
*/ 7Kw'Y8
publicclass UserManagerImpl implements UserManager { 4[lFurH
!2t7s96
private UserDAO userDAO; CCTU-Xz/
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/**
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* @param userDAO The userDAO to set. h&4s%:_4
*/ LL<xygd
publicvoid setUserDAO(UserDAO userDAO){ >a8iY|QY
this.userDAO = userDAO; *fN+wiPD
} # ~<]z
:qm\FsO
/* (non-Javadoc) \[9VeqMU
* @see com.adt.service.UserManager#listUser )^:H{1'
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(org.flyware.util.page.Page) =-sTV\
*/
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public Result listUser(Page page)throws jE0oLEg&
^Iw$(
HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); $>)0t@[f
if(totalRecords == 0) M 5#wz0
throw new ObjectNotFoundException 'lIs`Zc5N
ysnW3q!@
("userNotExist"); 5>}$]d/o
page = PageUtil.createPage(page, totalRecords); rbvk.:"^w
List users = userDAO.getUserByPage(page); vr;`h/
returnnew Result(page, users); )n&hO_c/
} HXq']+iC
JM7mQ'`Ud
} ?L<B]!9HZt
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5RPG3ppS
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r;Sk[Y5#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 u=:f%l
/+*"*Br/
询,接下来编写UserDAO的代码: bZ*=fdh
3. UserDAO 和 UserDAOImpl: u99a"+
java代码: TOwqr T/
w)dnmrKDZg
V 20h\(\\
/*Created on 2005-7-15*/ tSHW"R
package com.adt.dao; 2cCiHEL #
+M"j#H
import java.util.List; wR%Ta -
3aW<FSgP
import org.flyware.util.page.Page; ImN'o4vo
FGDVBUY@
import net.sf.hibernate.HibernateException; aAjl
58
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/** z +MH co"
* @author Joa lu.]R>w
*/ y_m+&Oe
publicinterface UserDAO extends BaseDAO { aHN"I
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publicList getUserByName(String name)throws ]}3s/NJi
\_Bj"K
HibernateException; 9KVJk</:n
]BO:*&O
publicint getUserCount()throws HibernateException; R U)(|;
wn"}<ka
publicList getUserByPage(Page page)throws "B QnP9
nCY kUDnZ
HibernateException; C8m 9H8Qm
b,'O|s]"Sc
} 01A{\O1$j
`
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>jt2vU@t.
SwOW%o
k8D_
java代码: K1@Pt}
</ [.1&S+\
S= 4o@3%$
/*Created on 2005-7-15*/ /3,/j)`a
package com.adt.dao.impl; ovKM;cRs/
ABCm2$<
import java.util.List; Yg&(kmm
gG?@_ie
import org.flyware.util.page.Page; 7P1Pk?pxy
4)gG_k
import net.sf.hibernate.HibernateException; x7S\-<8
import net.sf.hibernate.Query; !Gmnck&+
V,-we|"
import com.adt.dao.UserDAO; &5 "!0
3^/w`(-{@
/** >V6t
L;+
* @author Joa }Ulxt:}
*/ r `PJb5^\|
public class UserDAOImpl extends BaseDAOHibernateImpl L-|l$Ti"
@:>]jp}uq
implements UserDAO { 0:V/z3?
\V-N~_-H
/* (non-Javadoc) )ce 6~
* @see com.adt.dao.UserDAO#getUserByName 5f*_K6 ,v
D40 vCax^J
(java.lang.String) 3"x_Y
*/ _ $a3lR
publicList getUserByName(String name)throws H$%MIBz>$
Cx TAd[az
HibernateException { flCT]ZR
String querySentence = "FROM user in class _/1/{
G'JHimP2j
com.adt.po.User WHERE user.name=:name"; ">[#Ops-;$
Query query = getSession().createQuery *D|a`R!Y
%n|
(querySentence); _wKwiJs
query.setParameter("name", name); Jxvh;
return query.list(); h ;*x1BVE
} YYQvt
F{x+1hct0
/* (non-Javadoc) sa'1hX^@
* @see com.adt.dao.UserDAO#getUserCount() /"X_{3dq?
*/ W9?*
~!
publicint getUserCount()throws HibernateException { AX`Tku
int count = 0; #QwkRzVoy
String querySentence = "SELECT count(*) FROM \B#tB?rA
&l+Qn'N
user in class com.adt.po.User"; 0x<ASfka
Query query = getSession().createQuery ^+yz}YFM
c5^HGIe1
(querySentence); $9G&
wH>{
count = ((Integer)query.iterate().next PMAz[w,R~
s[8. l35|
()).intValue(); Y:DopKRD
return count; JvO1tA]ij
} H_?rbz} o
z"4 q%DC
/* (non-Javadoc)
5Cdn
j
* @see com.adt.dao.UserDAO#getUserByPage ]o'o
v
&GLDoLk6[
(org.flyware.util.page.Page) k-ZO/yPo
*/ ,-6Oma
-
publicList getUserByPage(Page page)throws :|bL2T@>[
vm@V5oH
HibernateException { ) ^En
String querySentence = "FROM user in class M86"J:\u]
p)SW(pS
com.adt.po.User"; mOJdx-q?r
Query query = getSession().createQuery BeUyt
] hT\"5&6
(querySentence); 5M>h[Q"R
query.setFirstResult(page.getBeginIndex()) vaeQ}F
.setMaxResults(page.getEveryPage()); -@XSDfy7S
return query.list(); pN^g.
} #aX#gh}1
HR-'8?)R.A
} ?;l@yx
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[KA^+n
sTd@/>S?p
t~L4wr{B
至此,一个完整的分页程序完成。前台的只需要调用 J_7w_T/
TJv .T2|
userManager.listUser(page)即可得到一个Page对象和结果集对象 `"=Hk@E
%6q82}# `
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]faj j\
$2uC%er"H
webwork,甚至可以直接在配置文件中指定。 myj/93p}`b
20}HTV{v
下面给出一个webwork调用示例: l9\W=-'
java代码: kEh\@x[
4ior
ovp/DM
/*Created on 2005-6-17*/ Qhj']>#g
package com.adt.action.user; 1i#y>fUj
0PkX- .
import java.util.List; i`+w.zJOH8
qiet<F
import org.apache.commons.logging.Log; 2B4.o*Q\
import org.apache.commons.logging.LogFactory; TyV~2pcN
import org.flyware.util.page.Page; L!:NL#M
:|(YlNUv
import com.adt.bo.Result; )Ra:s>
import com.adt.service.UserService; eQi^d/yi
import com.opensymphony.xwork.Action; WD%(RC"Q
&-*l{"7p+%
/** ]0>
* @author Joa 8)S)!2_h
*/ ^$'{:i
publicclass ListUser implementsAction{ b"X1
a]Pi2:S
privatestaticfinal Log logger = LogFactory.getLog %fg6',2
H@-q NjM
(ListUser.class); +=/j+S`
wnC-~&+6
private UserService userService; eZ:iW#YF
/rpr_Xw}
private Page page; ^1 ){
@(
6
5zx<
privateList users; hr]+4!/
Vja 4WK*
/* waMV6w)<
* (non-Javadoc) i1x4$}
* *w;?&)8%
* @see com.opensymphony.xwork.Action#execute() S
}`f&
*/ 4P#jMox
publicString execute()throwsException{ >8/Otg+h
Result result = userService.listUser(page); M.Q
HE2
page = result.getPage(); v/
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users = result.getContent(); hwM<0Jf
return SUCCESS; "81'{\(I_
} <6;M\:Y*T
rd&d~R6
/** $W|JQ h
* @return Returns the page. ,~cK]!:>s
*/ 5
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public Page getPage(){ \SmsS^z(]
return page; WT\wV\Pu
} mW]dhY 3X
X_'tgP9
/** S$SCW<LuN
* @return Returns the users. c9c]1XJ
*/ K^o$uUBe
publicList getUsers(){ IwYfs]-
return users; 2@bOy~$A
} J t.<Z&
8{0XqE~ix=
/** SOG(&)b
* @param page GI{EP&