Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :-j/Y'H_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fAD
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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 [L?WM>]%
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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 /Mw0<#
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分页支持类: &izk$~
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java代码: `'ak/%Krh
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package com.javaeye.common.util; ;eP.B/N
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import java.util.List; Su k;##I
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publicclass PaginationSupport { qO>A6
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publicfinalstaticint PAGESIZE = 30; }5y]kn
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privateint pageSize = PAGESIZE; D/tFN+|P
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privateList items; 2&:nHZ)
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privateint totalCount; ,772$7x
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privateint[] indexes = newint[0]; w=ZK=@
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privateint startIndex = 0; Bacmrf
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public PaginationSupport(List items, int HG)h,&nc-
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totalCount){
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setPageSize(PAGESIZE); l6T5]$
setTotalCount(totalCount); ?8$h%Ov-
setItems(items); @eRv`O"
setStartIndex(0); |@dY[VK>
} (E \lLlN
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public PaginationSupport(List items, int }M${ _D
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totalCount, int startIndex){ YF13&E2`\
setPageSize(PAGESIZE); CjU?3Ag
setTotalCount(totalCount); oTf^-29d
setItems(items); |]OI)w*
setStartIndex(startIndex); ,h'omU7
} vVH*\&H\T
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public PaginationSupport(List items, int rv%^2h<&
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totalCount, int pageSize, int startIndex){ I(+%`{Wv
setPageSize(pageSize); 3E;<aCG?
setTotalCount(totalCount); %F] :nk`
setItems(items); g#[,4o;
setStartIndex(startIndex); 0vcFX)]yW
} Wp//SV
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publicList getItems(){ u=sZFr@m[
return items; 6"La`}B(T8
} qZX\riR
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publicvoid setItems(List items){ ^-K~y
this.items = items; t/a
} t<znz6
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publicint getPageSize(){ TuzH'F
return pageSize; ;V4f6[<]'z
} s6_[H
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publicvoid setPageSize(int pageSize){ ~tqDh(
this.pageSize = pageSize; 'h;x>r
} ]PZ\N~T
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publicint getTotalCount(){ F vHd`
return totalCount; H)i%\7F5
} PYW>
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publicvoid setTotalCount(int totalCount){ $(;0;!t.
if(totalCount > 0){ ,%,.c^-
this.totalCount = totalCount; 9C\@10 D
int count = totalCount / u'aWvN y+
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pageSize; 8\CmM\R
if(totalCount % pageSize > 0) :tBZu%N/N
count++; d]Mjr2h
indexes = newint[count]; be~'}`>
for(int i = 0; i < count; i++){ yx/.4DW1Ua
indexes = pageSize * ?a` $Y>?h
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i; iPt{v5}]
} 4$8\IJ7G
}else{ S{c;n*xf
this.totalCount = 0; 0vcM+ }rw
} 3H@29TrJ+
} e"v oXe
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publicint[] getIndexes(){ bd3q207>
return indexes; `rI[
} XnV$}T:?X
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publicvoid setIndexes(int[] indexes){ firiYL"=44
this.indexes = indexes; B e2yS]U
} BI0 A0
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publicint getStartIndex(){ F[==vte|
return startIndex; RTv zS]
} oH kjMqju
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publicvoid setStartIndex(int startIndex){ 5`[B:<E4
if(totalCount <= 0) w1
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this.startIndex = 0; Q)}z$h55
elseif(startIndex >= totalCount) 5tl uS
this.startIndex = indexes HDT-f9%}<4
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[indexes.length - 1]; 2V =bE-
elseif(startIndex < 0) "3:TrM$|A
this.startIndex = 0; $7bux1L
else{ glP
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this.startIndex = indexes pt-
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[startIndex / pageSize]; y7Sj^muBY
} m6M:l"u
} Zywx.@!
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publicint getNextIndex(){ ~3s\Q%
int nextIndex = getStartIndex() + =hB0p^a
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pageSize; 8S7 YVsDz"
if(nextIndex >= totalCount) ouR(l;
return getStartIndex(); gPg2Ve0Qy
else nW`EBs
return nextIndex; TGu]6NzyZ
} <Z8^.t)|
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publicint getPreviousIndex(){ 7.tEi}O&_g
int previousIndex = getStartIndex() - g\foBK:GE
k;?E,!{
pageSize; L64cCP*
if(previousIndex < 0) X"3Za[9j
return0; h5.AM?*TNd
else ]~-vU{
return previousIndex; ,Frdi>7 ~
} )m[dfeqd +
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} 5RhP^:i@C
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抽象业务类 w0 0Ba^W
java代码: *q |3QHZ
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/** \]+57^8r
* Created on 2005-7-12 N(BCe\FV
*/ `<^1Ik[g
package com.javaeye.common.business; 3WQ"3^G
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import java.io.Serializable; bjYaJtn
import java.util.List; #Do#e
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import org.hibernate.Criteria; B!zqvShF
import org.hibernate.HibernateException; cJ!C=J
import org.hibernate.Session; ,=Fn6'
import org.hibernate.criterion.DetachedCriteria; yCG<qQz
import org.hibernate.criterion.Projections; @%sr#YqY
import 1I -LGe[Q
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org.springframework.orm.hibernate3.HibernateCallback; lc2RMu
import FkJX)
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org.springframework.orm.hibernate3.support.HibernateDaoS 8'6$t@oT9w
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upport; cPm-)/E)i
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import com.javaeye.common.util.PaginationSupport; N"wp2w
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public abstract class AbstractManager extends [#-!&>
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HibernateDaoSupport { WbP*kV{
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privateboolean cacheQueries = false; c/\$AJV.H
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privateString queryCacheRegion; yL>wCD,L
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publicvoid setCacheQueries(boolean ,t=12R]>
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cacheQueries){ )mb RG9P
this.cacheQueries = cacheQueries; XU19+mW=P
} J%n{R60b
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publicvoid setQueryCacheRegion(String SJdi*>
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queryCacheRegion){ C5^eD^[c
this.queryCacheRegion = `DPR >dd@
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queryCacheRegion; $ZOKB9QccC
} (66DKG
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publicvoid save(finalObject entity){ (ATCP#lF
getHibernateTemplate().save(entity); 8K/o /
} q4rDAQyPO
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publicvoid persist(finalObject entity){ Lv{xwHnE
getHibernateTemplate().save(entity); )"o+wSI1
} ^3:DeZf!u
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publicvoid update(finalObject entity){ ;y{VdT
getHibernateTemplate().update(entity); :9Vd=M6,
} +e6c4Tw/
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publicvoid delete(finalObject entity){ '#b7Z?83C
getHibernateTemplate().delete(entity); _7M! b9oA
} ToB^/
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publicObject load(finalClass entity, Mn=5yU
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finalSerializable id){ )5Bkm{v3
return getHibernateTemplate().load a} w%k
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(entity, id); X0.-q%5
} P6E=*^^m(
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publicObject get(finalClass entity, v 8`)h<:W?
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finalSerializable id){ M5Twulz/w
return getHibernateTemplate().get 'C9H6)Zq)
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(entity, id); gAY%VFBP0
} dTV:/QM
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publicList findAll(finalClass entity){ p~sfd
return getHibernateTemplate().find("from OZ$"P<X_"
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" + entity.getName()); D-8>?`n\
} BI\+NGrB
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publicList findByNamedQuery(finalString '%m0@5|hCD
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namedQuery){ =!#iC?I
return getHibernateTemplate 4#qjRmt
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().findByNamedQuery(namedQuery); <}E^r_NvD
} IFX|"3[$
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publicList findByNamedQuery(finalString query, YW}1iT/H
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finalObject parameter){ Qn7l-:`?
return getHibernateTemplate 1x0 7ua@(v
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().findByNamedQuery(query, parameter); P'Fy,fNg
} hao0_9q+
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publicList findByNamedQuery(finalString query, sX&M+'h
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finalObject[] parameters){ h]94\XQ>$
return getHibernateTemplate rI:KZ}GZ
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().findByNamedQuery(query, parameters); F$K-Q;r]<
} Z w5\{Z0
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publicList find(finalString query){ .'SXRrn&:C
return getHibernateTemplate().find 3_atv'I
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(query); <(JsB'TK
} n/"T7Y\2
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publicList find(finalString query, finalObject 6bg+U`&g
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parameter){ $p4aNC
return getHibernateTemplate().find {zGIQG9
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(query, parameter); V=|^r?
} Y\T*8\h_[
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public PaginationSupport findPageByCriteria ~zz |U!TG
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(final DetachedCriteria detachedCriteria){ T^a {#B
return findPageByCriteria 13Z6dhZu
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); W4CI=94
} $/C<^}A
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public PaginationSupport findPageByCriteria ]tZ5XS
h6x+.}}
(final DetachedCriteria detachedCriteria, finalint &1Fcwj
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startIndex){ 7atYWz~yG
return findPageByCriteria .;tO;j|6
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(detachedCriteria, PaginationSupport.PAGESIZE, 4C/8hsn
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startIndex); hkgPC-
} +&\TdvNI4
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public PaginationSupport findPageByCriteria J'O`3!Oy/
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(final DetachedCriteria detachedCriteria, finalint =] 5;=>(
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pageSize, l1cBY{3QD
finalint startIndex){ LbR/it'}
return(PaginationSupport) eq/5$b(
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getHibernateTemplate().execute(new HibernateCallback(){ !E_uQ?/w]Z
publicObject doInHibernate z K8#gif@
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(Session session)throws HibernateException { p2~Q
Criteria criteria = &SN$D5U'
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detachedCriteria.getExecutableCriteria(session); o33{tUp'
int totalCount = +lha^){
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((Integer) criteria.setProjection(Projections.rowCount 8
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()).uniqueResult()).intValue(); >q &ouVE
criteria.setProjection *A\NjXJl~
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(null); .%wEuqW=0
List items = )Qxv9:X
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criteria.setFirstResult(startIndex).setMaxResults ,.`^Wx6F
6 qKIz{;
(pageSize).list(); !v;r3*#Nky
PaginationSupport ps = UuT[UB=x5
)N=b<%WD
new PaginationSupport(items, totalCount, pageSize, /1li^</|p`
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startIndex); A}y1v;FB
return ps; c0G/irK
} deTbvl
}, true); RO.(k!J .
} vWkKNB
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public List findAllByCriteria(final wCt+{Y3T
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DetachedCriteria detachedCriteria){ Ok`U*j
return(List) getHibernateTemplate )vU{JY;
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().execute(new HibernateCallback(){ H+5]3>O-$
publicObject doInHibernate aY:(0en]&
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(Session session)throws HibernateException { +~fu-%,k
Criteria criteria = J#x91Jh
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detachedCriteria.getExecutableCriteria(session); ,;d9uG2
return criteria.list(); mTP.W#N
} [d&Faa[`
}, true); BWPYHWW}E
} NUnP'X=J,
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public int getCountByCriteria(final l wg.'<
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DetachedCriteria detachedCriteria){ Z],"<[E
Integer count = (Integer) _5m }g!
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getHibernateTemplate().execute(new HibernateCallback(){ <aHt6s'
publicObject doInHibernate \34|9#*z-
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(Session session)throws HibernateException { F>b6fUtR
Criteria criteria = Uqpvj90sw
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detachedCriteria.getExecutableCriteria(session); f.P( {PN
return w%_BX3GTO
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criteria.setProjection(Projections.rowCount 8_,ZJ9l;
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()).uniqueResult(); }[DAk~
} G2^DukK.
}, true); VDPN1+1*
return count.intValue(); z>0"T2W
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} (;j7{(
} @iP6N
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用户在web层构造查询条件detachedCriteria,和可选的 OWjZ)f/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Vx*q'~4y!|
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PaginationSupport的实例ps。 4AM*KI
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ps.getItems()得到已分页好的结果集 \Cs<'(=
ps.getIndexes()得到分页索引的数组 S }n;..{
ps.getTotalCount()得到总结果数 J9 =gv0
ps.getStartIndex()当前分页索引 bvx:R ~E$
ps.getNextIndex()下一页索引 *Z:PB%d5
ps.getPreviousIndex()上一页索引 "XY?v8*c
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;9PM?Iy[
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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 DsX>xzM
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一下代码重构了。 dvD<>{U,8
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我把原本我的做法也提供出来供大家讨论吧: WNb$2q=
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首先,为了实现分页查询,我封装了一个Page类: EDo@J2A
java代码: @(cS8%wK
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/*Created on 2005-4-14*/ <n\.S
package org.flyware.util.page; `g1Oon_
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/** QB[s8"S
* @author Joa I5L7BTe
* #I?iR3u
*/
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publicclass Page { '| }}og
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/** imply if the page has previous page */ {K9E% ,w
privateboolean hasPrePage; c Vn+~m_%
V)2_T!e%*
/** imply if the page has next page */ =b7&(x
privateboolean hasNextPage; dNQSbp
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/** the number of every page */ pD# "8h
privateint everyPage; %d0S-.
aHC;p=RQ\A
/** the total page number */ .e"Qv*[^
privateint totalPage; (g m^o{
X^Y9T`mQ}
/** the number of current page */ pCmJY
privateint currentPage; Fw9``{4w
nEm7&Gb
/** the begin index of the records by the current =.E(p)fz
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query */ 9@Sb! 9h
privateint beginIndex; &XRFX 5gP
@6q$Zg/
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/** The default constructor */ ;n!X% S<z*
public Page(){ F?} *ovy
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} f hG2
} qv-lO
/** construct the page by everyPage XyphQ}\u
* @param everyPage E ZKz-}
* */ r$FM8$cJ
public Page(int everyPage){ z[%v_S
this.everyPage = everyPage; vkpV,}H
} rO$>zdmYHs
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/** The whole constructor */ Ro]IE|Fv
public Page(boolean hasPrePage, boolean hasNextPage, !>y}Xq{bm3
+)JqEwCrq
|u ;BAb
int everyPage, int totalPage, /JeqoM"x
int currentPage, int beginIndex){ W<91m*
this.hasPrePage = hasPrePage; &PuJV + y
this.hasNextPage = hasNextPage; 3cO[t\/up
this.everyPage = everyPage; +g6j=%
this.totalPage = totalPage; )ek 5
this.currentPage = currentPage; aRKRy
this.beginIndex = beginIndex; KOEi_9i}
} DD 5EHJR
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/** **r?
* @return k^5Rf
* Returns the beginIndex. |D`b7h
*/ Y"kS!!C>[
publicint getBeginIndex(){ u7zB9iQ&
return beginIndex; SE)j}go
} tc<M]4-
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/** o>;0NF| }
* @param beginIndex sQAc"S
* The beginIndex to set. WFB|lNf&
*/ T{4fa^c2J
publicvoid setBeginIndex(int beginIndex){ 1+tt'
this.beginIndex = beginIndex; R}X_2""
} jjwMvf.R
uAS8F=9xP
/** >?W;>EUH
* @return Xb@z7X#O!
* Returns the currentPage. FP9<E93br
*/ g~hk-nXL.
publicint getCurrentPage(){ d<GG(
return currentPage; q\t>D
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} *DCNu{6
i?_D]BY4
/** x]><}!\<&
* @param currentPage zg Y*|{4Sl
* The currentPage to set. 0rJ\e
*/ Ya&\ly
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publicvoid setCurrentPage(int currentPage){ <6b\i5j
this.currentPage = currentPage; V@n(v\F
} <fsn2[V:B%
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/** QjjJtKz
* @return Na 9l#
* Returns the everyPage. $
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*/ .V 3X#t
publicint getEveryPage(){ PP[)h,ZL*
return everyPage; #D LT-G0
} $F@L$&~
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/** zNr_W[
* @param everyPage <aSLm=
* The everyPage to set. _h=<_Z
*/ AV[P QI
publicvoid setEveryPage(int everyPage){ JIbzh?$aD
this.everyPage = everyPage; W3{<e"
} iWN.3|r
$:u7Dv}\
/** 3@TG.)N4
* @return C*y6~AYN#
* Returns the hasNextPage. r< ?o}Qq
*/ O{ %A&Ui
publicboolean getHasNextPage(){ 0]eh>ab>
return hasNextPage; !OoaE* s
} me[J\MJ;w^
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/** ksOANLRN
* @param hasNextPage ( ln
* The hasNextPage to set. (m3I#L
*/ :S99}pgY
publicvoid setHasNextPage(boolean hasNextPage){ 9u7n/o&8v6
this.hasNextPage = hasNextPage; 8A8xY446)
} V:G }=~+=
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/** x)#<.DX
* @return <7FP"YU
* Returns the hasPrePage. $;)noYo
*/ i^sDh>$J
publicboolean getHasPrePage(){ qSC~^N`
return hasPrePage; f}lT|.)?VD
} DA4edFAuE
q(&^9"
/** _]=TFz2O
* @param hasPrePage t.>te'DK/
* The hasPrePage to set. n$m]58w
*/ )Vg{Y [!
publicvoid setHasPrePage(boolean hasPrePage){ OHtgn
this.hasPrePage = hasPrePage; }W@#S_-e8
} ,Og[[0g
VO @
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/** K.#,O+-Kg`
* @return Returns the totalPage. /UaNYv/
* C6D=>%uY
*/ liCCc;&B;
publicint getTotalPage(){ RQ*|+~H
return totalPage; <r7qq$
} e"o6C\c
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/** HoIKx_
* @param totalPage s;-78ejj7
* The totalPage to set. +YQ~t,/
*/ FU]8.)`G
publicvoid setTotalPage(int totalPage){ hk7(2j7B
this.totalPage = totalPage; liugaRO8J
} gc,J2B]61
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} \sHy. {
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*@ <8&M9x
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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 ~ F?G5cN5
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个PageUtil,负责对Page对象进行构造: ?O<`h~'$+
java代码:
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+
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/*Created on 2005-4-14*/ =qV4Sje|q
package org.flyware.util.page; ;"d ,~nLn
@pqY9_:P1
import org.apache.commons.logging.Log; J+3\2D?
import org.apache.commons.logging.LogFactory; dJ%wVY0z=
VVI8)h8
/** fW5"4,
* @author Joa !7mvyc!'!
* (E"&UC[
*/ uKR\Xo}
publicclass PageUtil { so?pA@O
cotxo?)Zv
privatestaticfinal Log logger = LogFactory.getLog o;M.Rt\A
|n|U;|'^
(PageUtil.class); -!'Oy%a#
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/** F.~n
* Use the origin page to create a new page *2 qh3
* @param page _S9rF-9G]
* @param totalRecords q9W~7
* @return .q5J^/kr
*/ 54ak<&?
publicstatic Page createPage(Page page, int #Dj"W8'zh
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totalRecords){ 95.qAFB1
return createPage(page.getEveryPage(), cW81
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page.getCurrentPage(), totalRecords); z9k*1:
} *<`7|BH 3
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/** LPq*ZZK
* the basic page utils not including exception ?r
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handler u"`5
* @param everyPage {\vI9cni|"
* @param currentPage 'h!h!
* @param totalRecords ULp)T`P
* @return page %|: ;Ti
*/ ;=5@h!@R
publicstatic Page createPage(int everyPage, int Qa,NGP.
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currentPage, int totalRecords){ 90
everyPage = getEveryPage(everyPage); 1KeJd&e
currentPage = getCurrentPage(currentPage); egZyng
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int beginIndex = getBeginIndex(everyPage, V;>9&'Z3
L
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currentPage); pchQ#GU
int totalPage = getTotalPage(everyPage, A|p@\3P*A
}Kvh`@CiJ
totalRecords); Nd]0ta
boolean hasNextPage = hasNextPage(currentPage, XAjd
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B,~f "
totalPage); i&A{L}eCr:
boolean hasPrePage = hasPrePage(currentPage); .+{nA}Bc
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returnnew Page(hasPrePage, hasNextPage, :[y]p7;{f
everyPage, totalPage, r+imn&FK8
currentPage, g8%MOhg
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beginIndex); bWGyLo,
} 6@"Vqm|HD
@IEI%vH
privatestaticint getEveryPage(int everyPage){ >|l;*Kw,/P
return everyPage == 0 ? 10 : everyPage; 8ku?
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} d4jVdOq2
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privatestaticint getCurrentPage(int currentPage){ T{_1c oL
return currentPage == 0 ? 1 : currentPage; @PYW|*VS
} E)KB@f<g*
ShC_hi
privatestaticint getBeginIndex(int everyPage, int Jy]FrSm^
8!Wfd)4=,F
currentPage){ =jJ H^Y2
return(currentPage - 1) * everyPage; jK3giT
} T$: >*
WuBmdjZ
privatestaticint getTotalPage(int everyPage, int !a' K &
IkSX\*
totalRecords){ e{v,x1Y_z(
int totalPage = 0; L@7Qs6G2u
pwa.q
if(totalRecords % everyPage == 0) Q{H17]W
totalPage = totalRecords / everyPage; wY' "ab
else M%7`8KQ
totalPage = totalRecords / everyPage + 1 ; @''&nRC1
w@87]/ 4Rq
return totalPage; +n@f'a">
} JzHqNUn*M
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privatestaticboolean hasPrePage(int currentPage){ " <<A
return currentPage == 1 ? false : true; 7sj<|g<h(_
} U5|B9%:&
[<_"`$sm=
privatestaticboolean hasNextPage(int currentPage, MB1sQReOO
4O$ mR
int totalPage){ pgCd
return currentPage == totalPage || totalPage == A ?#]s
#.~ga7Q
0 ? false : true; lo"j )Zt
} [m~b[ZwES
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} q_-ma_F#s
-<8B,
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^&C&~}Zv
uK"^*NEC';
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。 1#/6r :
g+e:@@ug
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 +H41]W6
,Qat
做法如下: ,oBlJvm
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :aHcPc:
=.DTR5(_h
的信息,和一个结果集List: l+t #"3
java代码: ;?0_Q3IML
_B}9f
~D*b3K8X
/*Created on 2005-6-13*/ <'W=]IAV
package com.adt.bo; ldK>HxM%Z
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import java.util.List; }6<)yW}U
h5x*NM1Ih
import org.flyware.util.page.Page; =D{B}=D\IM
}I\-HP8!gv
/** :=y0'f
V(@
* @author Joa Dzo{PstM%
*/ e"*BHvy F
publicclass Result { R_7
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private Page page; UIQQ\,3
~
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private List content; :]yg
`Uv)Sf{
/** DTPay1]6
* The default constructor 8}bZ[
*/ "t=UX
-3
public Result(){ &D]&UQf
super(); 5qC:yI
} }X.>4\B5
3!>/smb!
/** +yCTH
* The constructor using fields .xEJaID\N
* c&
3#-DNI
* @param page <8f(eP\*F
* @param content U7E
*/ o_sQQF
public Result(Page page, List content){ l^ARW
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this.page = page; \9'!"-i
this.content = content; p'gb)nI
} ?d4Boe0-a2
NIaF 5z
/** YwGHG{?e
* @return Returns the content. jM]d'E?ZLA
*/ wrabyRjK
publicList getContent(){ *o!l/>4g
return content; @7fm1b
} :\mRtVH
jP+ pA e
/** 2)=la%Nx
* @return Returns the page. U,'EF[t
*/ n08;
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public Page getPage(){ ;Xyte
return page; Q70bEHLA
} .9OFryo
IfMpY;ow=
/** 9qr UM`z$g
* @param content Z^*NnL.'
* The content to set. )yrAov\z*
*/ ./7v",#*.'
public void setContent(List content){ {c@G$
this.content = content; K^aj@2K{
} }"n7~|
qi&D+~Gv!
/** Ib6(Bp9.L
* @param page d/]|657u
* The page to set. N 'i,>
*/ -6`;},Yr
publicvoid setPage(Page page){ a8zZgIV
this.page = page; nkRK+~>
} E?cZbn*>`
} L<=) @7
(UGol[f<
'B`#:tX^N
c" +zgP
#]y5zi
2. 编写业务逻辑接口,并实现它(UserManager, Tm_8<$ 7
;%Q&hwj
UserManagerImpl) ' S ,2
java代码: &{ ZSE^
4jGLAor|
B)6#Lp3
/*Created on 2005-7-15*/ t.)AggXj#
package com.adt.service; 3fp> 4;ym'
qp&4 1
import net.sf.hibernate.HibernateException; `|EH[W&y
Pw{"_g
import org.flyware.util.page.Page; krjN7&
k;Hnu
import com.adt.bo.Result; 4H-j
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kYlg4 .~M
/** oRq3 pO}f
* @author Joa CW-A e
*/ _*E!gPO
publicinterface UserManager { #ib^Kg
c+2sT3).D
public Result listUser(Page page)throws NAJVr}4f
7Cy<mS
HibernateException; 9B=1Yr[
ertBuU
} Kam]Mn'
@5E,:)T*wR
7$7n71o
b#a@rh
J633uH}}
java代码: 7W|Zq6pi
=9$mbn
r
'zxoRc-b@N
/*Created on 2005-7-15*/ oHX$k{6
package com.adt.service.impl; uR_F,Mp?%u
/_*>d)
import java.util.List; wa ky<w,
X#ZgS!Mn
import net.sf.hibernate.HibernateException; 5)M2r!\
Fw"$A0
import org.flyware.util.page.Page; ~5 >[`)
import org.flyware.util.page.PageUtil; 55m<XC
Y(r@v
import com.adt.bo.Result; bfdVED
import com.adt.dao.UserDAO; p/*"4-S
import com.adt.exception.ObjectNotFoundException; <2<87PU
import com.adt.service.UserManager; pbLGe'
d~Mg
vh'
/** i_ QcC
* @author Joa BJ5}GX!
*/ BQ#L+9%
publicclass UserManagerImpl implements UserManager { m@\ZHbq
@Y-TOCadT
private UserDAO userDAO; 0^&!6R
2|{V,!/cvG
/** l r~gG3
* @param userDAO The userDAO to set. hs(W;tR@W
*/ ; LMWNy4
publicvoid setUserDAO(UserDAO userDAO){ Wi$dZOcSJ
this.userDAO = userDAO; FjFwvO_.
} Fo}7hab
_Y!sVJ){,c
/* (non-Javadoc) x_!ZycEa
* @see com.adt.service.UserManager#listUser CS@&^SEj
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(org.flyware.util.page.Page) .:9s}%Zr
*/ R#eg^7HfX
public Result listUser(Page page)throws F,T~\gO5,
1*UNsEr
HibernateException, ObjectNotFoundException { LchnBtjn
int totalRecords = userDAO.getUserCount(); &tE.6^F
if(totalRecords == 0)
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throw new ObjectNotFoundException 'jjb[{g^}}
$$1qF"GF
("userNotExist"); gQouOjfP
page = PageUtil.createPage(page, totalRecords); RiR:69xwR*
List users = userDAO.getUserByPage(page); e;ty !)]
returnnew Result(page, users); 79BaDB`{a
} `.v(fC
s|-FH X
} yPgmg@G@/
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8)wt$b
hfrnxeM#~
C@gXT]Q
0}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "A[ b
rG
|d}MxS`^
询,接下来编写UserDAO的代码: 2UadV_s+s
3. UserDAO 和 UserDAOImpl: _MfD
java代码: k
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e@n!x}t8
L?RF;jf
/*Created on 2005-7-15*/ nE|@IGH
package com.adt.dao; Em^(
yL1CZ_
import java.util.List; ?c#$dc"
||eAE)
import org.flyware.util.page.Page; M+xdHBg
R_kQPP
import net.sf.hibernate.HibernateException; Q@QFV~
k6**u
/** ;[$n=VX`
* @author Joa -<f;l_(
*/ `<fh+*
publicinterface UserDAO extends BaseDAO { 9|WV~
ga0'zo9K
publicList getUserByName(String name)throws Ph,-sR
cQUC.TZ_
HibernateException; ,)fkr]`<
\2kPq>hu
publicint getUserCount()throws HibernateException; ^g>1U5c
~?Omy8#
publicList getUserByPage(Page page)throws z@VP:au
L,]=vba'$
HibernateException; Tg
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Hs(D/&6%
} .v\\Tq&"|
~;#MpG;e
"!UVs+)]
Es'Um,ku
XFqJ 'R
java代码: =A!S/;z>
[aqu}Su
,/,9j{|"j
/*Created on 2005-7-15*/ :Vuf6,
package com.adt.dao.impl; & >JDPB?5
lU2c_4
import java.util.List; 7;}l\VXHm
o>lmst%<
import org.flyware.util.page.Page; yTBS=+X
;LwqTlJ*[L
import net.sf.hibernate.HibernateException; yL1bS|@
import net.sf.hibernate.Query; z2yJ#
M>H=z#C>/A
import com.adt.dao.UserDAO; my.`k'
W WG /k17
/** 'mM jjG9
* @author Joa }_OM$nzj
*/ fI|[Z+"
public class UserDAOImpl extends BaseDAOHibernateImpl f4('gl9
5g
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implements UserDAO { d/,E2i{I7
\5><3*\
/* (non-Javadoc) 8v92Ng7
* @see com.adt.dao.UserDAO#getUserByName &tI#T)SSs
,?-\
x6
(java.lang.String) m"/g7w4N
*/ !~iGu\y
publicList getUserByName(String name)throws vS?odqi#n
xytr2V ]aV
HibernateException { qr(`&hB-L
String querySentence = "FROM user in class Ug"rJMZG
!.HnGb+
com.adt.po.User WHERE user.name=:name"; g!J0L7i|
Query query = getSession().createQuery /Z%>ArAx
I!: z,t<
(querySentence); NCS!:d:Ry
query.setParameter("name", name); H{G{H=K_
return query.list(); ]B4}eBt5)@
} %i0\1hhV<
yJJ4~j){l
/* (non-Javadoc) KLQ!b,=q
* @see com.adt.dao.UserDAO#getUserCount() 9IZu$-
*/ QLq@u[A
publicint getUserCount()throws HibernateException { 8Jr?ZDf`
int count = 0; 8<#U9]
String querySentence = "SELECT count(*) FROM rR{,)fX;
4sFv?W
user in class com.adt.po.User"; ":W%,`@$
Query query = getSession().createQuery GH4iuPh]
!.X.tc
(querySentence); )@g;j>
count = ((Integer)query.iterate().next lC?Icn|o
zY9H%
()).intValue(); 0Bolv_e
return count; XSRdqU>Aun
} X" R<J#4
mxG ]kqi
/* (non-Javadoc) /!xF?OmVd
* @see com.adt.dao.UserDAO#getUserByPage 6vy7l(%
_D!g4"
(org.flyware.util.page.Page) x5si70BKC/
*/ tbDoP
Y
publicList getUserByPage(Page page)throws E+xuWdp.*
m6n!rRQ^U
HibernateException { K\.5h4k
String querySentence = "FROM user in class $p* p
=[tSd)D,y
com.adt.po.User"; 2 h|e
Query query = getSession().createQuery (M-ZQ
-
H#d:kil Ny
(querySentence); i8pU|VpA
query.setFirstResult(page.getBeginIndex()) {U11^w1"3
.setMaxResults(page.getEveryPage()); b\55,La
return query.list(); Jobiq]|>
} U]4pA#*{|
yfNX7
} l:(Rb-Wy
iZ,YxN<R
6tjcAsV
:osz
!dcwq;Ea
至此,一个完整的分页程序完成。前台的只需要调用 p9ZXbAJ{
7S^""*Q^
userManager.listUser(page)即可得到一个Page对象和结果集对象 c'fSu;1
1&)_(|p[C
的综合体,而传入的参数page对象则可以由前台传入,如果用
:Ao!ls'=
@1RP/y%
webwork,甚至可以直接在配置文件中指定。 l5t2\Fl
Ss?CfRM
下面给出一个webwork调用示例: T=Z.U$
java代码: M^madx6`
_GtBP'iN
#
'|'r+
/*Created on 2005-6-17*/ B5am1y{P#
package com.adt.action.user; .V'V:;BE%
A7XnHPIw
import java.util.List; QDmYSY$
Uu p(6`7
import org.apache.commons.logging.Log; U HO_Z
import org.apache.commons.logging.LogFactory; ]gb=
import org.flyware.util.page.Page; S[:xqzyDg
irBDGT~
import com.adt.bo.Result; g^>#^rLU
import com.adt.service.UserService; v Y|!
import com.opensymphony.xwork.Action; JcO08n
B/uniR^x
/** wFn[9_`*
* @author Joa l95<QI
*/ &