Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }fZ`IOf
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Pf<[|yu4?
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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 ]ikomCg
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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 4-R^/A0
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分页支持类: En6H%^d2
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java代码: `_vB+a
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package com.javaeye.common.util; _:g&,2bc
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import java.util.List; (;_FIUz0
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publicclass PaginationSupport { .]x2K-Sf
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publicfinalstaticint PAGESIZE = 30; -%CoWcGP
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privateint pageSize = PAGESIZE; @+LfQY
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privateList items; @U{<a#
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privateint totalCount; &a,OfSz
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privateint[] indexes = newint[0]; a4MZ;5
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privateint startIndex = 0; TUIk$U?/I
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public PaginationSupport(List items, int N587(wZ
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totalCount){ &HW1mNF9
setPageSize(PAGESIZE); X2|Y
setTotalCount(totalCount); N8r*dadDd
setItems(items); en F :>H4
setStartIndex(0); (1R?s>3o
} L!Cz'm"Nl
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public PaginationSupport(List items, int Pmg)v!"
(ll*OVL
totalCount, int startIndex){ iRV~Il#~!
setPageSize(PAGESIZE); FR[ B v
setTotalCount(totalCount); uX/$CM
setItems(items); OZY, @c
setStartIndex(startIndex); e({9]
} S~Z|PLtF
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public PaginationSupport(List items, int N2'qpxOLI
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totalCount, int pageSize, int startIndex){ }[+!$#
setPageSize(pageSize); l v&mp0V+
setTotalCount(totalCount); !$;a[Te
setItems(items); YgUH'P-
setStartIndex(startIndex); *l+OlQI0+
} ?>c=}I#Ui-
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publicList getItems(){ "9EE1];NT
return items; H5CR'Rp
} WtulTAfN
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publicvoid setItems(List items){ )tHaB,
this.items = items; LVJI_ O{fH
} ^N}Wnk7ks'
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publicint getPageSize(){ ^9OUzTF
return pageSize; >_dx_<75&
} "xmP6=1
g"s$}5{8:
publicvoid setPageSize(int pageSize){ ,#FLM`
this.pageSize = pageSize; 9E2j!
} xkNyvqcw
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publicint getTotalCount(){ 1OLqL
return totalCount; 5!YA o\S
} %J:SO_6
n% 'tKU\q
publicvoid setTotalCount(int totalCount){ Pi,QHb`>
if(totalCount > 0){ A1)wo^,
this.totalCount = totalCount; -oeL{9;
int count = totalCount / tM-^<V&
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pageSize; Q|Y0,1eVp|
if(totalCount % pageSize > 0) 7!,YNy%
count++; ]M/9#mD9~
indexes = newint[count]; RIu~ @
for(int i = 0; i < count; i++){ hz;|NW{u
indexes = pageSize * 7cAXd#sI
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i; -K,-h[o
} ]<(]u#g_d
}else{ Y2B&go
this.totalCount = 0; S##1GOO
} \^( 0B8|w
} 9a\nszwa
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publicint[] getIndexes(){ ;6@r-r
return indexes; IK,|5] *Ar
} D|Iur W1f
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publicvoid setIndexes(int[] indexes){ 6S6f\gAM
this.indexes = indexes; <FMq>d$\
} [b{CkX06
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publicint getStartIndex(){ b" xmqWa
return startIndex; CT0l!J~5m~
} ~\x:<)
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publicvoid setStartIndex(int startIndex){ %ms'n
if(totalCount <= 0) 1Je9,dd6
this.startIndex = 0; -jgysBw+Xb
elseif(startIndex >= totalCount) #&v/icz$
this.startIndex = indexes M(#m0xB
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[indexes.length - 1]; |KB0P@=a
elseif(startIndex < 0) :m86
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this.startIndex = 0; D=:04V}2+
else{ yC
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this.startIndex = indexes UnVm1ZWZ
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[startIndex / pageSize]; +("7ZK?
} @
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} gaA<}Tp,
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publicint getNextIndex(){ i)#:qAtP*
int nextIndex = getStartIndex() + vvUSeG\n#j
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pageSize; iAT)VQ&
if(nextIndex >= totalCount) ycFio ,
return getStartIndex(); GgaTn!mJt
else ZmOfEg|h\
return nextIndex; D\<y)kh
} zF5uN:-s
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publicint getPreviousIndex(){ %m:m}ziLQ
int previousIndex = getStartIndex() - zlR?,h-[3
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pageSize; 8|E'>+ D_-
if(previousIndex < 0) JS}{ %(B
return0; XLMb=T~S
else *'ZB*>
return previousIndex; >~`C-K#
} ^(viM?*
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} GGhM;%H_99
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抽象业务类 FU=w(< R;
java代码: JdZ+Hp3.
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/** ?g!V!VS2
* Created on 2005-7-12 iH^z:%dP
*/ -,K!
package com.javaeye.common.business; &3J@BMYp
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import java.io.Serializable; iNwqF0
import java.util.List; <b/~.$a'
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import org.hibernate.Criteria; oD}uOC}FS{
import org.hibernate.HibernateException; E( us'9c
import org.hibernate.Session; EGl^!.'
import org.hibernate.criterion.DetachedCriteria; "UwH\T4I
import org.hibernate.criterion.Projections; czlFr|O;
import 1s1=rZ!
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org.springframework.orm.hibernate3.HibernateCallback; <0S=,!
import 5>AX*]c
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org.springframework.orm.hibernate3.support.HibernateDaoS \M'-O YH_[
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upport; m7T)m0
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import com.javaeye.common.util.PaginationSupport; fib}b?vk
3>
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public abstract class AbstractManager extends 5q"ON)x
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HibernateDaoSupport { _)]CzBRq\6
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privateboolean cacheQueries = false; |lv|!]qAma
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privateString queryCacheRegion; d#2$!z#
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publicvoid setCacheQueries(boolean 'l,V*5L
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cacheQueries){ d;n."+=[x
this.cacheQueries = cacheQueries; a~8[<F omj
} wgd /(8d
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publicvoid setQueryCacheRegion(String !'LW_@
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queryCacheRegion){ V]90
this.queryCacheRegion = OzC\9YeA
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queryCacheRegion; 3]?#he
} HYmn:?H
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publicvoid save(finalObject entity){ UwC=1g U
getHibernateTemplate().save(entity); 9P{;HusNw
} ?ve#} \
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publicvoid persist(finalObject entity){ NY?;erX
getHibernateTemplate().save(entity); RoAlf+&Qb
} dK>7fy;mv
trE{ FT
publicvoid update(finalObject entity){ #pcP!
getHibernateTemplate().update(entity); :T9<der,
} %u;~kP|S%
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publicvoid delete(finalObject entity){ GKcv<G208
getHibernateTemplate().delete(entity); a'\o7_
} SM@QUAXO
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publicObject load(finalClass entity, q{+_
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finalSerializable id){ {/pm<k=
return getHibernateTemplate().load ;NRF=d>
d|4}obCt
(entity, id); `O'`eY1f
} 3MRc4UlB
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publicObject get(finalClass entity, fxT-j s#S
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finalSerializable id){ I[n^{8gz
return getHibernateTemplate().get U T="2*3gz
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(entity, id); ur$l Z0
} [|l?2j\
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publicList findAll(finalClass entity){ t'ZWc\
return getHibernateTemplate().find("from H<1WbM:w
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" + entity.getName()); >|;aIa@9
} MeUaTJFEB
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publicList findByNamedQuery(finalString xCtmXo
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namedQuery){ 0:b2(^]bg
return getHibernateTemplate RVeEkv[qp
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().findByNamedQuery(namedQuery); <\;#jF%V
} : >>@rF ,
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publicList findByNamedQuery(finalString query, 4Fm90O
NB<A>baL*
finalObject parameter){ 2+X\}s1vN
return getHibernateTemplate 'e6WDC1Am(
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().findByNamedQuery(query, parameter); t#2(j1
} XU"~h64]
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publicList findByNamedQuery(finalString query, J(6oL
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finalObject[] parameters){ P@FHnh3}Z$
return getHibernateTemplate DY^;EZ!hb
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().findByNamedQuery(query, parameters); QV\eMuNy
} ` Jdb ;
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publicList find(finalString query){ %HJK;
return getHibernateTemplate().find %plo=RF
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(query); db6mfxi
} x7$}8LZ"B
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publicList find(finalString query, finalObject y:6; LZ9[
_8E/)M
parameter){ &%-73nYw
return getHibernateTemplate().find ^#sU*trr
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(query, parameter); G.UI|r/Kz
} mrw=T.
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public PaginationSupport findPageByCriteria h2D>;k
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(final DetachedCriteria detachedCriteria){
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return findPageByCriteria /bVoErf
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 4#lo$#
} 9yfJVg
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public PaginationSupport findPageByCriteria ^f(@gS}?
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(final DetachedCriteria detachedCriteria, finalint 4F{70"a
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startIndex){ ej"+:."\e
return findPageByCriteria hq #?kN
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(detachedCriteria, PaginationSupport.PAGESIZE, G
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startIndex); aca=yDs2
} &Udb9
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public PaginationSupport findPageByCriteria ,l)^Ft`5
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(final DetachedCriteria detachedCriteria, finalint UNBH
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pageSize, g?ULWeZg5
finalint startIndex){ _D+J!f^
return(PaginationSupport) X93!bB
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getHibernateTemplate().execute(new HibernateCallback(){ ZEx}$<)_
publicObject doInHibernate Ll4g[8
<q@a~'Ai?!
(Session session)throws HibernateException { sL$:"=
Criteria criteria = )<tI!I][j
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detachedCriteria.getExecutableCriteria(session); c.e2 M/
int totalCount = i ,/0/?)*_
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((Integer) criteria.setProjection(Projections.rowCount PGoh1Uu
BGX.U\uc
()).uniqueResult()).intValue(); sdo[D
criteria.setProjection nX`u[ks
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(null); +csi[c)3E
List items = #%h-[/
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criteria.setFirstResult(startIndex).setMaxResults *vwbgJG! *
73\JwOn~
(pageSize).list(); 3z c U%*
PaginationSupport ps = N <Xq]!
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@P?~KW6<|
new PaginationSupport(items, totalCount, pageSize, io8'g3<
] &Rx@&e*
startIndex); "9Q40w\
return ps; =D<PVGo9
} Rw0qcM\>|
}, true); |3KLk ?2
} Jh!I:;/
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public List findAllByCriteria(final :BV6y|J9O^
B e0ND2oo
DetachedCriteria detachedCriteria){ _dhgAx-H)h
return(List) getHibernateTemplate 9j6QX~,
)O@]uY
().execute(new HibernateCallback(){ M# %a(Y3K)
publicObject doInHibernate NdD`Hn-
z)r=+ -
(Session session)throws HibernateException { lUMS;H(
Criteria criteria = /~$WUAh
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detachedCriteria.getExecutableCriteria(session); 2OVRf0.R~
return criteria.list(); waj0"u^#
} =E#%'/ A;c
}, true); 2KYw}j|5
} sW'2+|3"
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public int getCountByCriteria(final .Z
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DetachedCriteria detachedCriteria){ :Ra,Eu
Integer count = (Integer) Xx0hc 8qd
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getHibernateTemplate().execute(new HibernateCallback(){ #PH~1`vl
publicObject doInHibernate lHPd"3HDK
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(Session session)throws HibernateException { mQ|v26R
Criteria criteria = !u[eaLxV
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detachedCriteria.getExecutableCriteria(session); ic#`N0s?
return VKG&Y_7N
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criteria.setProjection(Projections.rowCount 'R'*kxf
V8C:"UZ;
()).uniqueResult(); pUQ/03dp
} p;3O#n-_
}, true); `-J%pEIza
return count.intValue(); ZJzt~
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} afuOeZP
} _4U5
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7'W%blg!V
用户在web层构造查询条件detachedCriteria,和可选的 {byBcG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1VG4S){}\9
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PaginationSupport的实例ps。 aJbO((%$|u
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ps.getItems()得到已分页好的结果集 Gi?/C&1T
ps.getIndexes()得到分页索引的数组 V)~.~2$
ps.getTotalCount()得到总结果数 QSdHm
ps.getStartIndex()当前分页索引 v4`"1Ss,K
ps.getNextIndex()下一页索引 (3Two}
ps.getPreviousIndex()上一页索引 .*Ct bGw
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 wnEyl[ac
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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 YQ9'0F[l
i@)i$i4
一下代码重构了。 '
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我把原本我的做法也提供出来供大家讨论吧:
-pf}
N~goI#4
首先,为了实现分页查询,我封装了一个Page类: (_mnB W
java代码: N `5,\TR2f
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/*Created on 2005-4-14*/ Zw5Ni Xj
package org.flyware.util.page;
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/** "U>JM@0DNm
* @author Joa 0WZ_7C?
* -Ta9 pxZk
*/ 8dZSi
publicclass Page { LsqA**=
iNtaDX|%/
/** imply if the page has previous page */ B%)%
privateboolean hasPrePage; O`x;,6Vr
1PVtxL?1P
/** imply if the page has next page */ v7BA[j Qr
privateboolean hasNextPage; B(LWdap~
=n5zM._S-
/** the number of every page */ "}u.v?HYz
privateint everyPage; Xx."$l
#>b3"[ |
/** the total page number */ d6}r#\
privateint totalPage; $+8cc\fq
,<n}W+3
/** the number of current page */ E4`N-3
privateint currentPage; ]qethaNy
$2oTkOA
/** the begin index of the records by the current Zd^rNHhA
5{|7$VqPF
query */ BZ94NOOdw
privateint beginIndex; :~b3^xhc^
PWaw]*dFmy
nt 81Bk=
/** The default constructor */ [-65PC4aN
public Page(){ 5,3'=mA6
bR*-Ht+wd
} ;(f)&Yom
.*@;@06?
/** construct the page by everyPage FOv=!'So
* @param everyPage *W4m3Lq
* */ 9_# >aOqL
public Page(int everyPage){ 7`-Zuf
this.everyPage = everyPage; 3c#BKHNC
} %+@O#P
ypbe!Y<i]
/** The whole constructor */ m!|kW{B#A
public Page(boolean hasPrePage, boolean hasNextPage, 5L+>ewl
_GXk0Ia3`
j~2{lCT
int everyPage, int totalPage, 5gb|w\N>
int currentPage, int beginIndex){ v~f HYa>
this.hasPrePage = hasPrePage; A;;fACF8e
this.hasNextPage = hasNextPage; ciFmaM.
this.everyPage = everyPage; _Zp}?b5Q
this.totalPage = totalPage; nF54tR[
this.currentPage = currentPage; |'.*K]Yp
this.beginIndex = beginIndex; 1Ce@*XBU
} yQ_B)b
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/** !POl;%\
* @return 9A/\h3HrJ
* Returns the beginIndex. Hbj,[$Jb
*/ #X%~B'
publicint getBeginIndex(){ }6p@lla,%]
return beginIndex; PXK7b2fE.
} \l'm[jy>
Lz`E;k^
/** \s/s7y6b+
* @param beginIndex oiF}?:7Q7
* The beginIndex to set. ^ssK
*/ MuYk};f
publicvoid setBeginIndex(int beginIndex){ ;+e}aER&9
this.beginIndex = beginIndex; O!mvJD
} c&r70L,
8>trS=;n
/** (n*^4@"2
* @return > A Khf
* Returns the currentPage. $Z!`Hb
*/ ~qcNEl\-y
publicint getCurrentPage(){ NaPt"G
return currentPage;
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} m4TE5q% 3
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/** e bm])~ZL
* @param currentPage Uddr~2%(
* The currentPage to set. p31NIf`
*/ VvvRRP^q
publicvoid setCurrentPage(int currentPage){ 4H,`]B8(D
this.currentPage = currentPage; n(b(yXYm]
} 4~k\j
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/** 2"0es40;0
* @return %j:]^vqFA
* Returns the everyPage. aO]ZZleNS
*/ Z8# (kmBdB
publicint getEveryPage(){ 1e(E:_t
return everyPage; P?8GV%0$
} sR(9IW-
19&<|qTz
/** j.C`U(n}`
* @param everyPage :9O#ObFR
* The everyPage to set. {E
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*/ 7R`M,u~f2^
publicvoid setEveryPage(int everyPage){ ql<i] Y
this.everyPage = everyPage; cWEE%
} a;rdQ>
Te.Y#lCT$
/**
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* @return |2?'9<
* Returns the hasNextPage. QP@%(]f G
*/ ~c8?>oN(
publicboolean getHasNextPage(){ @E^~$-J5j
return hasNextPage; ~;QvWS
} z8jk[5z
3[\iQ*d }B
/** J{l1nHQZSu
* @param hasNextPage )hd@S9Z.Y
* The hasNextPage to set. VCu{&Sh*
*/ e&simX;W
publicvoid setHasNextPage(boolean hasNextPage){ *v;!-F&8>
this.hasNextPage = hasNextPage; c]$i\i#
} B268e
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/** ,`wXg
* @return pM^9c7@!:
* Returns the hasPrePage. Y&[1`:-~-
*/ ~res V
publicboolean getHasPrePage(){ :}yi-/_8!
return hasPrePage; @AKn@T5
} JIOh#VNU
\ ,7f6:
/** wAX1l*`
* @param hasPrePage O#x*iI%
* The hasPrePage to set. 3 j!3E
*/ }XZ'v_Ti
publicvoid setHasPrePage(boolean hasPrePage){ uXI_M)
this.hasPrePage = hasPrePage; X'wE7=29M
} |>27'#JC
V_>\9m
/** _,zA ^*b
* @return Returns the totalPage. _]04lGx27
* Scp7X7{N
*/ /,1D)0
publicint getTotalPage(){ l*ayd>`~x
return totalPage; \qR7mI/*
} `Y
BC
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/** tna .52*/
* @param totalPage @xQgY*f#
* The totalPage to set. *n;!G8\
*/ VOKZ dC-
publicvoid setTotalPage(int totalPage){ p%iGc<vHX
this.totalPage = totalPage; 3Dg,GaRk
} r^h4z`:L
x N=i]~
} ]Gpxhg
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8j Mk)-
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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 P6E3-?4j
&/mA7Vf>eR
个PageUtil,负责对Page对象进行构造: nS/)P4z
java代码: d1T,eJ}
B,M(@5wz
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/*Created on 2005-4-14*/ 1lq(PGX)
package org.flyware.util.page; j H19k}D
Acnl^x7Y1
import org.apache.commons.logging.Log; e.]K L('
import org.apache.commons.logging.LogFactory; i7]4W
t/ +=|*
/** ^sa#8^,K
* @author Joa jL(qf~c_
* =3|O%\
*/ c05TsMF&O
publicclass PageUtil {
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4/mig0"N.
privatestaticfinal Log logger = LogFactory.getLog >^%7@i:@U
0%,!jW{`
(PageUtil.class); "vXxv'0\f
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/** A{UULVp
* Use the origin page to create a new page F_Z- 8>P
* @param page ;} und*q
* @param totalRecords kdCUORMK
* @return .^N/peUq
*/ @[5xq
publicstatic Page createPage(Page page, int J%x6
xm%Um\Pb7
totalRecords){ D<|qaHB=
return createPage(page.getEveryPage(), e"/;7:J5\
] x\-$~E
page.getCurrentPage(), totalRecords); eK.e|z|
} j2Tr$gx<
ElS 9?Q+
/** r~N"ere26
* the basic page utils not including exception )A!>=2M`
(EK"V';
handler OC1I&",Ai|
* @param everyPage u1t%(_h
* @param currentPage $SM#< @
* @param totalRecords $tz;<M7B
* @return page )_{dWf1
*/ ulu9'ch
publicstatic Page createPage(int everyPage, int /E
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XD |E=s
currentPage, int totalRecords){ x;-.
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everyPage = getEveryPage(everyPage); ?g?L3vRK
currentPage = getCurrentPage(currentPage); )\sc83L
int beginIndex = getBeginIndex(everyPage, hy}8Aji&
hfnN@Kg?B}
currentPage); _$=
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int totalPage = getTotalPage(everyPage, .gG1kW A-
R>,:A%?^b5
totalRecords); io,M{Ib
boolean hasNextPage = hasNextPage(currentPage, i-bJS6
wB.Nn/p
totalPage); K)qF+Vb^j
boolean hasPrePage = hasPrePage(currentPage); m<{<s T
.jS~By|r
returnnew Page(hasPrePage, hasNextPage, #k_HN}B
everyPage, totalPage, $Z|ffc1
currentPage, F_Y7@Ei/
f` :i.Sr
beginIndex); /J04^6
} ,S'p%g
XEn*?.e
privatestaticint getEveryPage(int everyPage){ I*x[:)X8
return everyPage == 0 ? 10 : everyPage; Jj,U RD&0R
} G"X8}:}
R<sJ^nx
privatestaticint getCurrentPage(int currentPage){ t'BLVCu
return currentPage == 0 ? 1 : currentPage; (7XCA,KTGI
} W5?yy>S6N
V6t,BJjS
privatestaticint getBeginIndex(int everyPage, int `kbSu}
6T+FH;h
currentPage){ NG
return(currentPage - 1) * everyPage; 4AG\[f
8q
} j6>.n49_
.u:81I=w(
privatestaticint getTotalPage(int everyPage, int r) $+
(4'$y`Z
totalRecords){ 'rMN=1:iu"
int totalPage = 0; M&NB/
<@}I0
if(totalRecords % everyPage == 0) f8M$45A'
totalPage = totalRecords / everyPage; p!sWYui
else `!Ds6
totalPage = totalRecords / everyPage + 1 ; CamE'
*c%oN
|
return totalPage; o&`<+4
i
} 2WtRJi?b|
F#5B<I
privatestaticboolean hasPrePage(int currentPage){ 2P/K
K
return currentPage == 1 ? false : true; c6nflk.l
} A,\6nO67
k$H%.l;E
privatestaticboolean hasNextPage(int currentPage, '~ ,p[
%^I88,$&L
int totalPage){ ]l'Y'z,}
return currentPage == totalPage || totalPage == cgl*t+o&
9AxCiT.
0 ? false : true; /%0<p,T
} qHNE8\9
6)vSG7Ise
R
zf
} ms!r ef4`+
e*bH0'; q
BNd^qB ?
T :/,2.l
SfJ./ny
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }?z@rt^
0Z0:,!
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8zA=;~GHP
({JHZ6uZ
做法如下: TjQvAkT
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ,WJH}(h"D
io#&o;M<
的信息,和一个结果集List: TjHwjRa
java代码: ,0E{h}(
ZQ_xDKqRV
3}@_hS"^8
/*Created on 2005-6-13*/ iC W*]U
package com.adt.bo; d?:=PH
a@\D$#2r
import java.util.List; Pu"R,a
ow0!%|fO
import org.flyware.util.page.Page; rS4@1`/R
vG;zJ#c
/** AC;V
m: @{
* @author Joa hGbj0
*/ VQ0fS!5'
publicclass Result { q EP
4
L0&RvI#
private Page page; ax{ ;:fW
Y$Q|J4z
private List content; y`$Q\}fS
W?eu!wL#p
/** lu#LCG-.
* The default constructor 5v?;PX
*/ ;Ra+=z}>
public Result(){ 'v\L @"
super(); }|5VRJA
} /[ 6j)HIS
^bc;[x&N
/** }';D]c
* The constructor using fields *P 3V
* ?V}j`r8|\4
* @param page B Ce|is0
* @param content x7vctjM|
*/
BWrv%7
public Result(Page page, List content){ OvUI@,Ef
this.page = page; %e`$p=m
this.content = content; K
=wBpLB
} >IX/<
{);M
B 9T!j]'
/** Hewd4k
* @return Returns the content. 9elga"4:'
*/ *J+_|_0nlW
publicList getContent(){ 7C$
5
return content; ovwQ2TuK
} &f7fK|}
H-3Eo#b#
/** [tg^GOf '
* @return Returns the page. m$9w"8R
*/ Q 2A7mGN
public Page getPage(){ kKPi:G52F
return page; gqR)IVk>%
} 25NTIzI@@
S.Z9$k%
/** P
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* @param content P7
PB t
* The content to set. M\Gdn92pd
*/ $5v0m#[^
public void setContent(List content){ _DrJVC~6@
this.content = content; etd&..]J
} ,=aJVb=C
uZZU{U9h
/** a6:x"Tv
* @param page %lX%8Z$v
* The page to set. =CL}
$_
*/ [w\9as/ E
publicvoid setPage(Page page){ mKT>,M
this.page = page; p-%|P]&
} A<\JQ
} A/7X9ir
(_4;') 9
H"Klj_<dH0
tX!nsm1
p~ .8\bI=
2. 编写业务逻辑接口,并实现它(UserManager, hoT/KWD,
.))v0
UserManagerImpl) @:tj<\G]
java代码: G&;j6<h l
be e5
LTJc,3\,
/*Created on 2005-7-15*/ % aUsOB-RV
package com.adt.service; $5L0.$Tj
,*]d~Y
import net.sf.hibernate.HibernateException; 66#"
sz--27es
import org.flyware.util.page.Page; A~Xq,BxCV
Mc-)OtmG[
import com.adt.bo.Result; 15$4&=O
P/JK $nb
/** T6pLoaKu
* @author Joa *jMk/9oa<N
*/ D0mI09=GtQ
publicinterface UserManager { v`V7OD#:j]
9S[XTU
public Result listUser(Page page)throws >a1{397Y}
;.wX@
HibernateException; QRLJ_W^&u
=&!HwOnp
} ^E6d`2w-
9s}Kl($
^`SA'F,
f'q 28lVf
Z?J:$of*
java代码: X%bFN
cL8#S>>u.
e4I^!5)N
/*Created on 2005-7-15*/ y<XlRTy[}
package com.adt.service.impl; `o79g"kxe
iqhOi|!
import java.util.List; 0)Rw|(Fpo]
d7cg&9+
import net.sf.hibernate.HibernateException; ;nmM7TZ;
Gg\G'QU
import org.flyware.util.page.Page; 0Q5 93F
import org.flyware.util.page.PageUtil; kl1Y] ?z}
<Fs-3(V+\
import com.adt.bo.Result; 8u2+tB
import com.adt.dao.UserDAO; }.)s%4p8
import com.adt.exception.ObjectNotFoundException; 4gdY`}8b^}
import com.adt.service.UserManager; ;r=b|B9c
5j"1z1_&
/** ]WJfgN4
* @author Joa
L;W.pe0
*/ ">dq0gD
publicclass UserManagerImpl implements UserManager { tLm867`c7
Q\{x)|{$
private UserDAO userDAO; 3Dm8[o$Z
K#K\-TR|$
/** =He.fEy
* @param userDAO The userDAO to set. pz_e =xr
*/ 0;~yZ?6_F
publicvoid setUserDAO(UserDAO userDAO){ dMl+ko
this.userDAO = userDAO; YEYY}/YX
} Qq0l*)mX
oJ*1>7[ J
/* (non-Javadoc) 0MIUI<;j
* @see com.adt.service.UserManager#listUser |'HLz=5\
AB.(CS=i
(org.flyware.util.page.Page) .g\6g~n
*/ TTI81:fku
public Result listUser(Page page)throws K&A;Z>l,v5
77gysd\(
HibernateException, ObjectNotFoundException { xPmN},i'R$
int totalRecords = userDAO.getUserCount(); BOf1J1
if(totalRecords == 0) lm'Zy"~::
throw new ObjectNotFoundException z&nZ<ih
7N2\8kP
("userNotExist"); Q"J-tP!
page = PageUtil.createPage(page, totalRecords); 6R}j-1
<n
List users = userDAO.getUserByPage(page); a0Oe:]mo\
returnnew Result(page, users); -E&e1u,Mi
} ul5|.C
!)Ni dG
} 5b#QYu
us)*2`?6t
H5wb_yBQ+
H!IDV}dn
%4>x!{jwV
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >tRHNB_
i6no;}j
询,接下来编写UserDAO的代码: nl/UdgI
3. UserDAO 和 UserDAOImpl: "c`xH@D
java代码: !ZtSbOC '
V*jsq[q=
h.tY 'F
/*Created on 2005-7-15*/ va{#RnU
package com.adt.dao; o96:4j4
?Z %:
import java.util.List; S;@ay/*~
EU`T6M
import org.flyware.util.page.Page; {_ V0
S0@T0y#
import net.sf.hibernate.HibernateException; LZ~`29qw(
~o15#Pfn/
/** SHdL/1~t
* @author Joa b#Kq[}
*/ (wt+`_6
publicinterface UserDAO extends BaseDAO { k{Lv37H
*:_~Nn9_R;
publicList getUserByName(String name)throws W=-|`
):6-
HibernateException; 18!VO4u\I
)Id2GV~2B
publicint getUserCount()throws HibernateException; E)YVfM
!G=>ve
publicList getUserByPage(Page page)throws o<VP'F{p
!Rw&DFU
HibernateException; 8:g!w:$x
-wr(vE,
} )&1!xF
RR25Q.c
]EL\)xCr
f{Q p
]W9B6G_
java代码: 4~u9B/v
G!-J$@P
ku.A|+Tn
/*Created on 2005-7-15*/ ubGs/Vzye
package com.adt.dao.impl; cx(2jk}6
LM,fwAX
import java.util.List; 9&jPp4qG
w7Dt1axB
import org.flyware.util.page.Page; #\FT EY!
Q-('5a19J
import net.sf.hibernate.HibernateException; pt!'v$G/*
import net.sf.hibernate.Query; 3IyZunFT
Pz~q%J
import com.adt.dao.UserDAO; H7e /
Cd~LsdKE5
/** v}`1)BUeF
* @author Joa 9m!7|(QV
*/ #EwK"S~
public class UserDAOImpl extends BaseDAOHibernateImpl 9O;vUy)
G=$}5; t
implements UserDAO { 3V-6)V{KaE
CIQwl 6H9
/* (non-Javadoc) sJ6a7A8)
* @see com.adt.dao.UserDAO#getUserByName {e9Y
!oFg
~mA7pOHj
(java.lang.String) L+R>%d
s
*/ vfbe$4mH
publicList getUserByName(String name)throws TA)LPBG
rWr/ p^~
HibernateException { yh!B!v'
String querySentence = "FROM user in class ks:{TA27
d.\PS9l
com.adt.po.User WHERE user.name=:name"; l{EU_|q
Query query = getSession().createQuery `p|[rS>
%cj58zO|y
(querySentence); |\{Nfm=:%
query.setParameter("name", name); R+Lk~X^*l'
return query.list(); >l2w::l%
} >UN vkQ:
hWxT !
/* (non-Javadoc) iwo$\
* @see com.adt.dao.UserDAO#getUserCount() ~07RFR
*/ NhDA7z`b'J
publicint getUserCount()throws HibernateException { 4K,''7N3
int count = 0; [$:@X V(
String querySentence = "SELECT count(*) FROM qy9i9$8
x7gjG"V
user in class com.adt.po.User"; ak2dn]]D
Query query = getSession().createQuery d
Uz<1^L
uGCtLA+sL
(querySentence); F@<MT<TRf
count = ((Integer)query.iterate().next X%`KYo%
Xu%d,T$G
()).intValue(); Sh$U-ch@
return count; #~e9h9
} d$Em\*C
{G.jB/
/* (non-Javadoc) Z:^3Fm->+
* @see com.adt.dao.UserDAO#getUserByPage DPeVKyjU
{rfte'4;=
(org.flyware.util.page.Page) Y- ~;E3(
*/ GC?S];PL
publicList getUserByPage(Page page)throws g< )72-h
5G oK"F0i
HibernateException { -mC:r&Y>[
String querySentence = "FROM user in class d#7]hF
w`Xg%*]}
com.adt.po.User"; ^BNp`x;;`
Query query = getSession().createQuery #NMJZ
m+7`\|`jQ
(querySentence); q\_DJ)qpn
query.setFirstResult(page.getBeginIndex()) <i7agEdZD
.setMaxResults(page.getEveryPage()); ` U#Po_hq
return query.list(); WVkG2
} oek #^:pF
x/_dW
} oVEAlBm^v
<4$YO-:E
x
Ty7lfSe
N6BNzN}-P
pj@Yqg/
至此,一个完整的分页程序完成。前台的只需要调用 w5Z2N[hy
9b%|^.B
userManager.listUser(page)即可得到一个Page对象和结果集对象 [yvt1:q
LV\ieM
的综合体,而传入的参数page对象则可以由前台传入,如果用 We\Y \*!v
A?'
H[2]w"
webwork,甚至可以直接在配置文件中指定。 &/DOO ^
jQs*(=ls
下面给出一个webwork调用示例: 1W0.Ufl)
java代码: sSy$(%
\N yr=<c
AtT"RG-6
/*Created on 2005-6-17*/ 9nO(xJ"e4
package com.adt.action.user; 'tut4SwC
:r-.r"[m-
import java.util.List; *LEu=3lp%>
_y"a2M
import org.apache.commons.logging.Log; p4y6R4kyT
import org.apache.commons.logging.LogFactory; ]p\u$VY9
import org.flyware.util.page.Page; -B,c B
ZGzc"r(r:#
import com.adt.bo.Result; Vp\80D&
import com.adt.service.UserService; *f?S5.
import com.opensymphony.xwork.Action; =kF?_K N
lh~<s2[R2
/** ^+URv
* @author Joa b.@H1L
*/ Pm;I3r=R\
publicclass ListUser implementsAction{ u(8~4P0w
F6DxvyANr
privatestaticfinal Log logger = LogFactory.getLog {9 Db9K^
*afejjW[
(ListUser.class); PRZ8X{h
B3eNFS
private UserService userService; m}rh|x/?
f~U#z7
private Page page; G~`'E&/
U-1VnX9m
privateList users; %kJh6J
l$=Gvb
/* prqT (1
* (non-Javadoc) u*U_7Uw$
* 'Z59<Y a&x
* @see com.opensymphony.xwork.Action#execute() f>O54T .L.
*/ <3)|44.o&
publicString execute()throwsException{ k+f1sV[4}
Result result = userService.listUser(page); t[/\KG8
page = result.getPage(); 2'|XtSj
users = result.getContent(); ,YQ=Zk)w
return SUCCESS; $vW^n4!
} 0c`sb+?
:ao^/&HZ
/** 219R&[cb
* @return Returns the page. (I>HWRH
*/ prqyoCfq
public Page getPage(){ Y'2-yB
return page; F9F" F
} 3>H2xh 3Y
Tw}@+-
/** 8?A@/
* @return Returns the users. eSJAPU(D
*/ ]"C| qR*
publicList getUsers(){ YGfA qI
y
return users; gHp'3SnS
} >c}:
q|R+x7x
/** zoR,RBU6
* @param page $xLEA\s
* The page to set. e',hC0&S
*/ F1 9;RaP+
publicvoid setPage(Page page){ (6e!09P&
this.page = page; 9qnuR'BDu
} Tavtr9L0XY
_RN/7\
/** ) )fDOJ
* @param users dko [
* The users to set. ZYrKG+fkl
*/ Ewa[Y=+tx
publicvoid setUsers(List users){ "9)1K!tH
this.users = users; Gs^(YGtU
} bta0?O
#
UEN YJ*tnP
/** jQY>9+t
* @param userService }~myf\$
* The userService to set. <ur KIu
*/ T_3V/)%@
publicvoid setUserService(UserService userService){ }P05eI
this.userService = userService; Fsnw3/Nr
} l0eANB%Y=@
} b$;HI7)/K
] dW%g?
;%v%K+}r
9vB9k@9
sx<}
tbG
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, H4P\hOK7r
z:dXc
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 hVQ7'@
9m%7dsv
么只需要: sZ0g99eX
java代码: L+v8E/W
EG'7}W
P}ehNt*($
<?xml version="1.0"?> R1]v}f_I"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 3N(8|wh
<1ztj#B
1.0//EN" "http://www.opensymphony.com/xwork/xwork- !O 0ZD4/{4
34"{rMbQ
1.0.dtd"> ?q+8 /2
0L3Bo3:k
<xwork> gubb .EY
=YS!soO
<package name="user" extends="webwork- ]hCWe0F
s98: *o3
interceptors"> D<+ bzC
E#yCcC!wMY
<!-- The default interceptor stack name sV9{4T~#|
g
@c=Bt$
--> $#6Fnhh}
<default-interceptor-ref a7QlU=\
'US:Mr3
name="myDefaultWebStack"/> 9'L1KQ
^N*pIVLC
<action name="listUser" |HKHN?)
8cYuzt]..
class="com.adt.action.user.ListUser"> Ri^sQ<