Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 62)lf2$1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ;D"P9b]9$
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 "gN* J)!x
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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 V> a3V'
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分页支持类: 39T&c85
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java代码: |<3Q+EB^
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package com.javaeye.common.util; J4Z<Yt/
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import java.util.List; ?Y0$X>nm
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publicclass PaginationSupport { M,\|V3s
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publicfinalstaticint PAGESIZE = 30; Ec*--]j*c
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privateint pageSize = PAGESIZE; <Xs@ \
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privateList items; W_BAb+$aF
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privateint totalCount; 0J:U\S
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privateint[] indexes = newint[0]; h"BhTx7E}
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privateint startIndex = 0; VJl &Bq+
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public PaginationSupport(List items, int $: 4mOl
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totalCount){ &FJU%tFA
setPageSize(PAGESIZE); }GNkB
setTotalCount(totalCount); R5NRCI
setItems(items); 7<R6T9g
setStartIndex(0); C*{15!d:G
} HV*:<2P%D
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public PaginationSupport(List items, int a(x.{}uG,
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totalCount, int startIndex){ XU;{28P
setPageSize(PAGESIZE); L^5&GcHP0
setTotalCount(totalCount); @}&,W
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setItems(items); 3d#9Wyxs
setStartIndex(startIndex); U=c5zrs
} ^b"x|8
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public PaginationSupport(List items, int vbWJhjK0h
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totalCount, int pageSize, int startIndex){ ZM-/n>
setPageSize(pageSize); f
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setTotalCount(totalCount); KMpDlit
setItems(items); np`gcj#
setStartIndex(startIndex); k5fH;
}
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publicList getItems(){ p-T~x$"c|
return items; m0BG9~p|
} Sr ztTfY
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publicvoid setItems(List items){ =0C l
this.items = items; q*F~~J!P
} ]} 5I>l
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publicint getPageSize(){ q#Yg0w~
return pageSize; >%n8W>^^4
} -~(0O
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publicvoid setPageSize(int pageSize){ t3
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this.pageSize = pageSize; e-%7F]e
} ;Xfd1
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publicint getTotalCount(){ o7c%\v[
return totalCount; @H3 s2|
} }{#;;5KrB
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publicvoid setTotalCount(int totalCount){ :>tF_6
if(totalCount > 0){ S|{Yvyp
this.totalCount = totalCount; {UX"Epd);n
int count = totalCount / 5bF9IH
] 689 Q%D
pageSize; H7z>S G0
if(totalCount % pageSize > 0) AQnJxIL:
count++; z&C{8aQ'
indexes = newint[count]; -(/2_&"
for(int i = 0; i < count; i++){ 3D?IG\3
indexes = pageSize * :Bx+WW&P.i
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i; B&%L`v2[
} f"ZqA'KB#
}else{ zx\.2<K
this.totalCount = 0; ;uM34^
} ,-cpsN
} u=d`j
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publicint[] getIndexes(){ lgCHGv2@
return indexes; D+ah ok
} Hl^aUp.c
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publicvoid setIndexes(int[] indexes){ "xe7Dl
this.indexes = indexes; 4cXAT9
} b[J-ja.
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publicint getStartIndex(){ 8Ehy9<
return startIndex; G?Qe"4
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} L?3VyBE
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publicvoid setStartIndex(int startIndex){ lF;ziF
if(totalCount <= 0)
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this.startIndex = 0; i#L6UKe:Q
elseif(startIndex >= totalCount) _9Dn\=g
this.startIndex = indexes .x)>f
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[indexes.length - 1]; uD.
elseif(startIndex < 0) >Jm-2W5J
this.startIndex = 0; \&eY)^vw
else{ =gMaaGg p,
this.startIndex = indexes ' +)6#/*
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[startIndex / pageSize]; kdK*MUB
} FX7Cjo#=R
} _/8_,9H
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publicint getNextIndex(){ k9*J*7l-m
int nextIndex = getStartIndex() + ax-=n (
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pageSize; QE7+rBa
if(nextIndex >= totalCount) 0=N4O!X9
return getStartIndex(); vbr~<JT=
else 'P@=/
return nextIndex; ucQezmie
} K:}h\ In
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publicint getPreviousIndex(){ *)j@G:
int previousIndex = getStartIndex() - (/T+Wpy?
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pageSize; L/qZ ; {
if(previousIndex < 0) tpv?`(DDU
return0; oS[W*\7'!
else [TRGIGtq
return previousIndex; Bv;I0i:_
} $se !8s"
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} Am2*-
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抽象业务类 euRCBzc
java代码: /'-:=0a
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/** f2uZK!:m
* Created on 2005-7-12 k
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*/ B"~U<6s0
package com.javaeye.common.business; NY~ dM\
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import java.io.Serializable; LTg?5GwD\j
import java.util.List; \ua9thOG
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import org.hibernate.Criteria; j FgZ}Xp
import org.hibernate.HibernateException; cNdu.c[@
import org.hibernate.Session;
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import org.hibernate.criterion.DetachedCriteria; Sv.KI{;v$
import org.hibernate.criterion.Projections; \z2vV+f
import y' 2<qj
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org.springframework.orm.hibernate3.HibernateCallback;
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import Zkw J.SuU
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org.springframework.orm.hibernate3.support.HibernateDaoS S|l&fb n
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upport; {;U} :Dx
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import com.javaeye.common.util.PaginationSupport; D*|(
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public abstract class AbstractManager extends [Dnusp7e
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HibernateDaoSupport { w#W5}i&x
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privateboolean cacheQueries = false; t$aVe"uM
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privateString queryCacheRegion; H!p!sn
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publicvoid setCacheQueries(boolean |d5ggf.w
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cacheQueries){ #1MKEfv(~
this.cacheQueries = cacheQueries; 55LgBD
} @=CLeQG`
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publicvoid setQueryCacheRegion(String &q.)2o#Q.
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queryCacheRegion){ &u&2D$K,tp
this.queryCacheRegion =
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queryCacheRegion; 8^i[j\Y;6
} 5@K\c6
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publicvoid save(finalObject entity){ KUbJe)}g
getHibernateTemplate().save(entity); OE6#YT
} P;jlHZ 9?O
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publicvoid persist(finalObject entity){ RTA%hCr!
getHibernateTemplate().save(entity); C:Vv!u
} yj>){NcX
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publicvoid update(finalObject entity){ M\I_{Q?_
getHibernateTemplate().update(entity); fH&zR#T7U4
} E`~i-kf
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publicvoid delete(finalObject entity){ O!o <P5X^
getHibernateTemplate().delete(entity); :#qUMiu$
} 0(\p<qq
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publicObject load(finalClass entity, D^$]>-^
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finalSerializable id){ V_jiOT!
return getHibernateTemplate().load +5#x6[
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(entity, id); P?xA$_+
} 6F,/w:
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publicObject get(finalClass entity, [@g ~
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finalSerializable id){ f7.m=lbe
return getHibernateTemplate().get P7'M],!9w
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(entity, id); hUBF/4s\
} |%-YuD
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publicList findAll(finalClass entity){ B+|IZoR
return getHibernateTemplate().find("from t~q?lT
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" + entity.getName()); jBS'g{y-!
} ad9EG#mD#
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publicList findByNamedQuery(finalString f0OgK<.>T
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namedQuery){ CNq[4T'~A
return getHibernateTemplate f7ZA837Un
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().findByNamedQuery(namedQuery); Y!F!@`%G
} 'bl%Y).9w
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publicList findByNamedQuery(finalString query, <M=';h^w2
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finalObject parameter){ W|0My0y
return getHibernateTemplate sSNCosb
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().findByNamedQuery(query, parameter); _Cj(fFL
}
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publicList findByNamedQuery(finalString query, A4}#U=3tI
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finalObject[] parameters){ K0LbZMn,/
return getHibernateTemplate :4U0I:J#
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().findByNamedQuery(query, parameters); X'jr|s^s
} {-J:4*`
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publicList find(finalString query){ ?@>;/@
return getHibernateTemplate().find *CzCUu:%t
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(query); xvdY
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} dt<~sOT3s
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publicList find(finalString query, finalObject
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parameter){ JS PW>W"
return getHibernateTemplate().find T30Zk*V
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(query, parameter); h^Qh9G0dn
} ETe-
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public PaginationSupport findPageByCriteria 'Wtf>`
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(final DetachedCriteria detachedCriteria){ g1ytT%]
return findPageByCriteria dGU8+)2cn
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); TqAtcAurM
} (U _wp's
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public PaginationSupport findPageByCriteria H }B2A"
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(final DetachedCriteria detachedCriteria, finalint <>n9'i1
so*/OBte
startIndex){ y~dB5/
return findPageByCriteria SD^E7W$?
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(detachedCriteria, PaginationSupport.PAGESIZE, CIEJql?`
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startIndex); =&N$Vqn
} :6zC4Sr^
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public PaginationSupport findPageByCriteria 'bC]M3P
8<{;=m8cQ
(final DetachedCriteria detachedCriteria, finalint 5a6VMqQ6
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pageSize, 2uEhOi0I
finalint startIndex){ bQ"N
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return(PaginationSupport) 6< >SHw
*%I[ ke *
getHibernateTemplate().execute(new HibernateCallback(){ 4~Dax)
publicObject doInHibernate
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(Session session)throws HibernateException { nc&Jmo7
Criteria criteria = W_%W%i|
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detachedCriteria.getExecutableCriteria(session); e"~)Utk
int totalCount = wA631kr
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((Integer) criteria.setProjection(Projections.rowCount ogJ<e_m
nPOO3!<{
()).uniqueResult()).intValue(); 3}j1RYtz
criteria.setProjection Za0gs @$
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(null); VKNp,Lf
List items = `R0Y+#$8h
vtZ?X';wh
criteria.setFirstResult(startIndex).setMaxResults d/lffNS=
R:f7LRF/\
(pageSize).list(); -%H%m`wD
PaginationSupport ps = [IMQIX
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new PaginationSupport(items, totalCount, pageSize, r@yD8 D \
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startIndex); Dkw*Je#6PX
return ps; Z\' wm'
} PtqGX=u
}, true); 8 URj1 W
} :!']p2B
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public List findAllByCriteria(final U!0E_J
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DetachedCriteria detachedCriteria){ ;_N"Fdl
return(List) getHibernateTemplate O_AGMW/2+
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().execute(new HibernateCallback(){ R6<4"?*r
publicObject doInHibernate ZV(
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(Session session)throws HibernateException { wV:C<Mg7q
Criteria criteria = jtCZfFD?
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detachedCriteria.getExecutableCriteria(session); vhpvO>Q
return criteria.list(); 0bSz4<}
} : u-.T.zZl
}, true); )
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} N Bz%(?\
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public int getCountByCriteria(final 0;<OYbm3<
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DetachedCriteria detachedCriteria){ qtY
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Integer count = (Integer) 'evv,Q{87
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getHibernateTemplate().execute(new HibernateCallback(){ J=9 #mOcg"
publicObject doInHibernate SK-W%t
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(Session session)throws HibernateException { N5!&~~
Criteria criteria = anC+r(jjg9
L
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detachedCriteria.getExecutableCriteria(session); Up|f=@=
return Gkmsaf>
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criteria.setProjection(Projections.rowCount H#Q;"r 3
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()).uniqueResult(); u5F}( +4r
} Q7(eq0na
}, true); jyQVSQs
return count.intValue(); IN_gF_@%
} +*.1}r&
} t7^D-l
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用户在web层构造查询条件detachedCriteria,和可选的 3]`mQm E
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N9`97;.X
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PaginationSupport的实例ps。 OoM_q/oI
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ps.getItems()得到已分页好的结果集 [gZDQcU
ps.getIndexes()得到分页索引的数组 OL9]*G?F
ps.getTotalCount()得到总结果数 EneAX&SG
ps.getStartIndex()当前分页索引 4E'|.tt(
ps.getNextIndex()下一页索引 pl\b-
ps.getPreviousIndex()上一页索引 NjP ]My
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V{GXc:=
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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 @/(@/*+"
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一下代码重构了。 $3 vhddO
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我把原本我的做法也提供出来供大家讨论吧: ^ $wJi9D6
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首先,为了实现分页查询,我封装了一个Page类: L$}g3{
java代码: N8 M'0i?
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/*Created on 2005-4-14*/ gVA; `<
package org.flyware.util.page; Y%h}U<y
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/** n}:t<
* @author Joa NQR^%<hU
* C$K+=jT
*/ n$
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publicclass Page { zp#:EZ
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/** imply if the page has previous page */ H+R7X71{
privateboolean hasPrePage; ;Z4o{(/zU
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/** imply if the page has next page */ Xy!&^C` J`
privateboolean hasNextPage; RJ*F>2
#B}Qt5w
/** the number of every page */ 8 ?" Ze(
privateint everyPage; _25d%Ne0
V&R$8tpz
/** the total page number */ Pxk0(oBX
privateint totalPage; JaFUcpZk$
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/** the number of current page */ rg*^w!
privateint currentPage; gWi{\x8dt
hv{87`L'K(
/** the begin index of the records by the current v~aLTI
5}7ISNP;f
query */ Ju4.@
privateint beginIndex; 6J"(xT
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/** The default constructor */
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public Page(){ =+4 _j
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} 1I
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B#:E?a;{
/** construct the page by everyPage L&'l3|
* @param everyPage L:i+}F;M)s
* */ gZ*hkKN6
public Page(int everyPage){ N;g$)zCV1
this.everyPage = everyPage; k{1b20
}
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/** The whole constructor */ c(CJ{>F%
public Page(boolean hasPrePage, boolean hasNextPage, ?y46o2b*)
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int everyPage, int totalPage, Pfk{ =y
int currentPage, int beginIndex){ N"K\ick6J
this.hasPrePage = hasPrePage; QheDF7'z
this.hasNextPage = hasNextPage; A'`P2Am
this.everyPage = everyPage; X+%u(>>
this.totalPage = totalPage; T(gg>_'jh
this.currentPage = currentPage; %:%MUdl6
this.beginIndex = beginIndex; 4ODX5If
} cP J7E
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/** {IrJLlq
* @return 7~D`b1||
* Returns the beginIndex. 4/f[`].#W
*/ YLigP"*~^
publicint getBeginIndex(){ LC76 Qi;|k
return beginIndex; ho_4fDv
} smbUu/
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/** (qbc;gBy
* @param beginIndex UC(9Dz
* The beginIndex to set. $^ubo5%
*/ %^T!@uZr
publicvoid setBeginIndex(int beginIndex){ rX:1_q`xA
this.beginIndex = beginIndex; x~nQm]@`h
} 6}"lm]b
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/** TRo4I{L6S
* @return [m
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* Returns the currentPage. @| P3
*/ P.!;Uf}32
publicint getCurrentPage(){ [{?;c+[
return currentPage; -C=]n<ak
} K: 4P;ApI
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/** dhs#D:/{9
* @param currentPage K# /Ch5?
* The currentPage to set. dw3'T4TC?
*/ o3fR3P%$
publicvoid setCurrentPage(int currentPage){ gn364U a
this.currentPage = currentPage; @
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} 0T=jR{j!o
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/** W!y)Ho
* @return GgT=t)}wu
* Returns the everyPage. 48;~bVr}
*/ 6S)$3Is
publicint getEveryPage(){ `TOX1cmw
return everyPage; NPP3(3C
} +H[Q~P8'[
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/** 1ZKz3)K
* @param everyPage S7Qen6lm
* The everyPage to set. 6OMb`A@/2
*/ ]yw_n^@
publicvoid setEveryPage(int everyPage){ `9:v*KuM#R
this.everyPage = everyPage; xTGP
} cK/PQsMP
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/** 1O|RIv7F[/
* @return n|J.)E.
* Returns the hasNextPage. 8Er[M
*/ 7G?Ia%u
publicboolean getHasNextPage(){ y{:]sHyG
return hasNextPage; PMD,8] |
} X
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/** on6<l
* @param hasNextPage %}\ vW
* The hasNextPage to set. %+D-y+hn
*/ 9t.fij
publicvoid setHasNextPage(boolean hasNextPage){ Hxj'38Y
this.hasNextPage = hasNextPage; O\3r%=TF
} LRhP7D+A
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/** w/hh
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* @return }k4`
* Returns the hasPrePage. ,>:XE@xcp
*/ |dW2dQ
publicboolean getHasPrePage(){ @"jmI&hYn
return hasPrePage; Xqc'R5Cw
} S83]O!w0
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/** uPM8GIvZX.
* @param hasPrePage &@-1"-H
* The hasPrePage to set. Z3LQl(
*/ c1 gz#,
publicvoid setHasPrePage(boolean hasPrePage){ YK(XS"Kl
this.hasPrePage = hasPrePage; 0F-mROC=F
} ]JkpR aP$
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/** ;bUJ+6f:
* @return Returns the totalPage. *2w_oKE'+5
* eUzU]6h
*/ &C
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publicint getTotalPage(){ 41P4?"O
return totalPage; i=,B88ko
} ~ra#UG\Y8
6RR4L^(m
/** Z5"!0B^ j
* @param totalPage 6GvhEulYR
* The totalPage to set. fRZUY<t
*/ \VoB=Ac&
publicvoid setTotalPage(int totalPage){ QwKky ^A
this.totalPage = totalPage; PR48~K,?
} CnM+HN30o
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} #
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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 &!H~bzg
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个PageUtil,负责对Page对象进行构造: e'}ePvN
java代码: 6Cop#kW#
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/*Created on 2005-4-14*/ b/a?\0^
package org.flyware.util.page;
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import org.apache.commons.logging.Log; jQH5$
import org.apache.commons.logging.LogFactory; =B3!jir
FFD*e-i
/** GU;TK'Yy?
* @author Joa uFA|rX
* *il]$i
*/ 0ECO/EuCg
publicclass PageUtil { n $D}0wSM/
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privatestaticfinal Log logger = LogFactory.getLog es*_Oo1
s>9z+;~!
(PageUtil.class); %l9WZ*yZ`2
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/** Z
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* Use the origin page to create a new page !."%M^J
* @param page ;f\R$u-
* @param totalRecords !ch[I#&J-
* @return )%H5iSNG$P
*/ B5?c'[V9
publicstatic Page createPage(Page page, int gMoyy
'Wx\"]:
totalRecords){ 5VoOJ_hq
return createPage(page.getEveryPage(), SevfxR
g'd*TBnk
page.getCurrentPage(), totalRecords); +Y.uZJ6+
} q7)]cY_
cLN[o8ZU
/** ]HZa:aPY
* the basic page utils not including exception '<{oYXZW3
%~8](]p
handler >M8^Jgh
* @param everyPage Aoy1<8WP%
* @param currentPage .zSimEOF
* @param totalRecords s[{:>~{iq
* @return page -x3tx7%
*/ "p6:ekw
publicstatic Page createPage(int everyPage, int +QCU]Fozk
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currentPage, int totalRecords){ 8KGv?^M
6W
everyPage = getEveryPage(everyPage); I/e2,
currentPage = getCurrentPage(currentPage); |GVGny<
int beginIndex = getBeginIndex(everyPage, &EbD.>Ci
;s!ns N
currentPage); hVt+%tmNy
int totalPage = getTotalPage(everyPage, .SKNIct
M
; ei<Q =[
totalRecords); !lt\2Ae
boolean hasNextPage = hasNextPage(currentPage, `|ck5DZT5L
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totalPage); hsQ rd%{f
boolean hasPrePage = hasPrePage(currentPage); AT'_0>x8
'nj&}A'
returnnew Page(hasPrePage, hasNextPage, fjK]m.w
everyPage, totalPage, \4`saM /x
currentPage, 7}iewtdy,
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beginIndex); _sf0{/< )
} 6{Cu~G{]N
=J[[>H'<d
privatestaticint getEveryPage(int everyPage){ GqK&'c
return everyPage == 0 ? 10 : everyPage; G,mH!lSm,
} ;5JIY7t
}TAGr 0
privatestaticint getCurrentPage(int currentPage){ 0z'={6,
return currentPage == 0 ? 1 : currentPage; LPm# 3U
} CrwcYzrRWl
;]#4p8lh+
privatestaticint getBeginIndex(int everyPage, int z"P,=M6De
#&`WMLl+8
currentPage){ l_q>(FoqA
return(currentPage - 1) * everyPage; ]rX?n
} )(|0KarF
=Gg)GSL^
privatestaticint getTotalPage(int everyPage, int $X<<JnsK
v BeU
totalRecords){ 4f @\f7\
int totalPage = 0; *O}'2Ht6\
C[<\ufclD
if(totalRecords % everyPage == 0) `S~@ FX
totalPage = totalRecords / everyPage; vdFQf ^l
else p7=^m>Z6
totalPage = totalRecords / everyPage + 1 ; :7PSZc:xE
!=Kay^J~.
return totalPage; ^N}~U5
} {msB+n~WZ
]!Aze^7;
privatestaticboolean hasPrePage(int currentPage){ H1ui#5n2
return currentPage == 1 ? false : true; MzW$Sl&:
} q D>Y}Z!
$O</akn;
privatestaticboolean hasNextPage(int currentPage, fdEj#Ux<H
N+@@EOmH
int totalPage){ Z
a
y'/b
return currentPage == totalPage || totalPage == rJ~(Xu>,s
= {DB
0 ? false : true; "BNmpP
} C00*X[p
&i}cC4i
jnLu| W&
} Nn4Kt,KY
:7;Iy u
g$+O<a@ n
~hw4gdtS
J-{E`ibGN
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。 Z5^UF2`Q
@3=<wz<
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 `2U/O .rV
a}]@o"
做法如下: kK6>>lD'
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 r
($t.iS
fOfz^W
的信息,和一个结果集List: }z2-|"H
java代码: WW/m
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g
wiC ,
-Z&{$J
/*Created on 2005-6-13*/ "_}D{ws1
package com.adt.bo; 8@#Y
<{
L}pFb@
import java.util.List; X)+sHcE~#
q&S.C9W
import org.flyware.util.page.Page; '(:J|DN
6Z}))*3 9
/** |#kf.kN
* @author Joa bL[W.O0
*/ g2_df3Q
publicclass Result { ! \Kh\
7lOiFw
private Page page; No|{rYYKK
Pz!yIj
private List content; 5gEWLLDp
PiQs><FK8
/** ^aoLry&i=
* The default constructor VqU:`?#"a
*/ w`_9 *AF9
public Result(){ &y?B&4|hM
super(); SSC!BcC1
} kniMXeiu
Q{-r4n|b
/** g>oLc6T
* The constructor using fields VlNzm
* <K'gvMG[
* @param page xKux5u_
* @param content l<6/ADuS
*/ 9hzU@m
public Result(Page page, List content){ @jeV[N,0
this.page = page; Yl=
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this.content = content; d(XWt;K K
} 4v
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jT0fF
/** 95&HsgdxJ
* @return Returns the content. =ByW`
*/ jL1UPN
publicList getContent(){ h]$zub
return content; WI3!?>d
} jnY4(B
F6/bq/s
/** 0qd`Pf
* @return Returns the page. Az[z} r4
*/ Y$^QH.h
public Page getPage(){ Y8T.RS0
return page; k,& QcYw
} Rz]bCiD3
B
N~(}?'y9S
/** |Gi/=[Tp
* @param content ZW"J]"A
* The content to set. E~ kmU{D
*/ %94"e7Hy
public void setContent(List content){ k,,}N9
this.content = content; :08UeEy
} W0k_"uI
}$ der
/** )uP= o
* @param page f?QD##~;
* The page to set. Kt(p|
*/ 2S3F]fG0
publicvoid setPage(Page page){ _DQdo
this.page = page; Cpl)byb
} .755-S
} ~7v^7;tT
R.@GLx_zpQ
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<Bwu N,}
]@EjKgs
2. 编写业务逻辑接口,并实现它(UserManager, =0S7tNut
eYFCf;
UserManagerImpl) k95vgn%
java代码: P+xZaf
H
O7W}Z1G
a%kj)ah
/*Created on 2005-7-15*/ !?96P|G
package com.adt.service; %zGPF
1EN5ZN,
import net.sf.hibernate.HibernateException; |zf||ju
Z6I!4K
import org.flyware.util.page.Page; Y*6*;0Kx
*T3"U|0_ y
import com.adt.bo.Result; {221@ zcCq
@0G}Q
/** IKt9=Tx
* @author Joa D~<GVp5T
*/ fN9hBC@
publicinterface UserManager { ^U1;5+2G+~
>z2{D7
public Result listUser(Page page)throws b$BUo8O}
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HibernateException; *\>&
+{s^"M2`
} aaBBI S
S"dQ@r9
$ 8s&=OW
oq|K:<l
@[^H*^1|g
java代码: W{%M+a[#l
0
[s1!Cm!i
D^pAf/ek@i
/*Created on 2005-7-15*/ |:AjQ&PM)
package com.adt.service.impl; T@L^RaPX
?h5Y^}8Qg
import java.util.List; 8n56rOW!
m+L:\mvA
import net.sf.hibernate.HibernateException; ;,<s'5icyg
B::vOg77
import org.flyware.util.page.Page; ,yC~{H
import org.flyware.util.page.PageUtil; F>&8b^v bn
up`6IWlLE
import com.adt.bo.Result; *Hs5MXNu
import com.adt.dao.UserDAO; Lczcz"t
import com.adt.exception.ObjectNotFoundException; :r\<DVj
import com.adt.service.UserManager; Tb}b*d3
ALG +
/** }"szL=s
* @author Joa ,HkJ.6KF
*/ |i|O9^*%
publicclass UserManagerImpl implements UserManager { $wBUu
=Vi+wH{xM
private UserDAO userDAO; , v R4x:W
}\9qN! ol
/** Q5Wb)
* @param userDAO The userDAO to set. ]UNmhF!W>u
*/ 2Bx\nLf/
K
publicvoid setUserDAO(UserDAO userDAO){ Q<M>+U;t
this.userDAO = userDAO; u}pLO9V"`
} D =3NI
R_-.:n%.z
/* (non-Javadoc) 0g1uM:;
* @see com.adt.service.UserManager#listUser ]`lTkh
O)hNHIF
(org.flyware.util.page.Page) iM\W"OUl[
*/ RW3&]l=
public Result listUser(Page page)throws s}5;)>3~@
B${Q Y)t
HibernateException, ObjectNotFoundException { RSp=If+4
int totalRecords = userDAO.getUserCount();
M; V2O;
if(totalRecords == 0) m49)c K?
throw new ObjectNotFoundException 7{p,<Uz<"U
ec{pWzAe
("userNotExist"); 5y.kOe4vH
page = PageUtil.createPage(page, totalRecords); |kjk{
List users = userDAO.getUserByPage(page); Tfj%Sb,zM
returnnew Result(page, users); 5YRa2#d
} AH ;h#dT
PJ);d>tz
} V
]Z{0
gI[xOK#
q$\KE4v"
1"i/*}M
H=*;3gM,'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 l{kum2DT
-c Mqq$
询,接下来编写UserDAO的代码: Obbjl@]
3. UserDAO 和 UserDAOImpl: \h :$q E7
java代码: UF?qL1w
m'Ran3rp
Ug/b;( dJ'
/*Created on 2005-7-15*/ qg|SBQ?6
package com.adt.dao; ]c*&5c$
aK'BC>uFI
import java.util.List; v&|o5om
Mu TlN
import org.flyware.util.page.Page; g$uj<"^
-_B*~M/vV`
import net.sf.hibernate.HibernateException; \\6/"
HG{OkDx]fl
/**
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* @author Joa |SCO9,Fs
*/ w?Y;pc}1B
publicinterface UserDAO extends BaseDAO { @2V#bK
L_Z>*s&
publicList getUserByName(String name)throws iXI >>9
a:C
ly9
HibernateException; G8j$&1`:
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publicint getUserCount()throws HibernateException; ttgb"Wb%S
]e!9{\X,*
publicList getUserByPage(Page page)throws [$$i1%c%Z<
Dz8)u:vRS
HibernateException;
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Tw8$6KUW
} eX>x
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`-IX"rf
lx(kbSxF
:hC+r=!I
4+Wti!s
java代码: -uX): h!
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|<gYzbq
/*Created on 2005-7-15*/ ]sB-}n)
package com.adt.dao.impl; |bDUekjR
E{*d`n
import java.util.List; 3,t3\`=
h_n`E7&bG
import org.flyware.util.page.Page; jYI\.bc
$cflF@3
import net.sf.hibernate.HibernateException; @#rF8;
import net.sf.hibernate.Query; g\:(1oY
WWZ`RY
import com.adt.dao.UserDAO; vL}e1V:
br`cxgZ0"
/** ?NWc3 .
* @author Joa -Q9} gaH_
*/ d0YDNP%,_
public class UserDAOImpl extends BaseDAOHibernateImpl muc6gwBp
54r/s#|-3
implements UserDAO { q8#zv_>K
Qq+$ea?>
/* (non-Javadoc) `)?N7g[\u
* @see com.adt.dao.UserDAO#getUserByName 0o7*5| T4
/fv;`?~d*
(java.lang.String) #TS:|=
*/ ,v ,#f
.
publicList getUserByName(String name)throws Qh3BI?GZ'3
}LeizbU
HibernateException { wwUa+6?
String querySentence = "FROM user in class (ZSd7qH"
d;@"Naw
com.adt.po.User WHERE user.name=:name"; ~HBQQt
Query query = getSession().createQuery VUmf;~
cao=O
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(querySentence); %?2y2O,;
query.setParameter("name", name); lu vrv m
return query.list(); l$/.B=]
} F#=M$j_
zl $mt'\y
/* (non-Javadoc) }JI@f14
* @see com.adt.dao.UserDAO#getUserCount() [0MNq]gxf
*/ ?sD4S
publicint getUserCount()throws HibernateException { OGcq]ue
int count = 0; _xY
dnTEl
String querySentence = "SELECT count(*) FROM Vq$8!#~w
mSeCXCrZlI
user in class com.adt.po.User"; l]R=I2t
Query query = getSession().createQuery +adwEYRrr
FNlS)Bs
(querySentence); '-X[T}
count = ((Integer)query.iterate().next Q-<h)WTA
6pP:Q_U$
()).intValue(); p?-qlPl
return count; vj%3v4
} 6({TG&`!]
i/|}#yw8A
/* (non-Javadoc) !{q_Q !
* @see com.adt.dao.UserDAO#getUserByPage z_f^L %J0
D| |)H
(org.flyware.util.page.Page) FdGnNDl*e
*/ ?mwa6]
publicList getUserByPage(Page page)throws Y#[xX2z9
D,\hRQ
HibernateException { cXw8#M!
String querySentence = "FROM user in class Lo,uH`qU
{^":^N)
com.adt.po.User"; {'cm;V+
Query query = getSession().createQuery fj|X`,TiZ;
tJ$gH;
(querySentence); 2Y>#FEW/
query.setFirstResult(page.getBeginIndex()) 4ibOVBG:*,
.setMaxResults(page.getEveryPage()); #?"^: ,Y
return query.list(); []:&WA9N
} Y6G`p
r(j :C%?}C
} ;W{2\ Es
+?)R}\\
#(7^V y&
'pj*6t1~
>t#5eT`_ w
至此,一个完整的分页程序完成。前台的只需要调用 d k/f_m
F1*xY%Jv^M
userManager.listUser(page)即可得到一个Page对象和结果集对象 ^ 6b27_=
+\-cf,WkI
的综合体,而传入的参数page对象则可以由前台传入,如果用 :'2h0
5R
R =kXf/y
webwork,甚至可以直接在配置文件中指定。
YWAH(
# Rhtaq9
下面给出一个webwork调用示例: x7GYWK
9
java代码: ]w0_!Z&
[2{2w68D!
Gv&%cq1
/*Created on 2005-6-17*/ ,n{R,]y\
package com.adt.action.user; A01PEVd@A
.;F%k,!v
import java.util.List; m$bYx~K
\NTVg6>qN
import org.apache.commons.logging.Log; X2T_}{
import org.apache.commons.logging.LogFactory; i&KBMx
import org.flyware.util.page.Page; } `Cc-X7
<!=:{&d%
import com.adt.bo.Result; GC`/\~TM
import com.adt.service.UserService; v,|jmv+:
import com.opensymphony.xwork.Action; [}I|tb>Pg
9zl-C*9vj
/** MbxJ3"@
* @author Joa $px1D$F !
*/ "[ieOFI
publicclass ListUser implementsAction{ ~p?D[]h
l}@C'Np
privatestaticfinal Log logger = LogFactory.getLog C<#_1@^:8e
[]doLt;J
(ListUser.class); rn]F97v@]
O{p7I&
private UserService userService; lWDSF]ZYV
*4/KK
private Page page; ASB3|uy _
lS|F&I5j
privateList users; {A~3/M%74;
j-d542"
/* woa|h"T
* (non-Javadoc) 5 qMP u|A
* 1HLU
&
* @see com.opensymphony.xwork.Action#execute() H#M;TjR
*/ 0a9[}g1=#
publicString execute()throwsException{ l{QlJ>%~{;
Result result = userService.listUser(page); BCO (,k
page = result.getPage(); dVMLn4[,MA
users = result.getContent(); >>c%Ic
return SUCCESS; MoXai0d%
} jX.'G
YZAQt*x
/** <qVOd.9c
* @return Returns the page. b/_u\R
]-'
*/ &oE'|^G
public Page getPage(){ cSjX/%*!m
return page; g 'Wr+(A_
} )Y`ybADd3
0+K<;5"63d
/** ,Iru_=Wk~
* @return Returns the users. w4FYd
*/ dkW7k^g
publicList getUsers(){ pgW^hj\
return users; %jJIR88
} Q9c*I,Oj
N/[!$B0H@
/** nbW.x7
* @param page a^Z=xlJ/uZ
* The page to set. mKoDy`s
*/ ['Qh#^p
publicvoid setPage(Page page){ If8Lt}-
this.page = page; ]z]=?;ty%
} \TLfLqA
t>Yl=79,
/** l
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* @param users Vh^ :.y
* The users to set. 3[@:I^q
*/ y4VO\N!
publicvoid setUsers(List users){ TEbIU8{Y
this.users = users; xVrLoAw
} "([lkn
q,OCA\
/** 7%&e4