Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 y^oSVj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 J8"Cw<=O
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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 (Js'(tBhiU
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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 7='M&Za
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分页支持类: " (+>#
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java代码: EnrRnVB
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package com.javaeye.common.util; ;!k1LfN
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import java.util.List; yp=2nU"o
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publicclass PaginationSupport { ^6~CA
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publicfinalstaticint PAGESIZE = 30; (l.`g@(L
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privateint pageSize = PAGESIZE; sYt8NsQ
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privateList items; > @ulvHL
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privateint totalCount; uE>2*u\
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privateint[] indexes = newint[0]; Ywf.,V
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privateint startIndex = 0; Zjt3U;Y
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public PaginationSupport(List items, int pbivddi2
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totalCount){ '$M=H.
setPageSize(PAGESIZE); ~PUz/^^
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setTotalCount(totalCount); &Q^M[X
setItems(items);
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setStartIndex(0); HzM^Zn57%
} ejwFQ'wTx
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public PaginationSupport(List items, int m?_S&/+*
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totalCount, int startIndex){ #Vanw !
setPageSize(PAGESIZE); v.+-)RLQg
setTotalCount(totalCount); 74%,v|
setItems(items);
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setStartIndex(startIndex); 3_IuK6K2
} }@V(y9K
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public PaginationSupport(List items, int 5isejR{r
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totalCount, int pageSize, int startIndex){ Z-b^{uP
setPageSize(pageSize); K ^1bR(a
setTotalCount(totalCount); _EOQ*K#=Ct
setItems(items); 9q;\;-
setStartIndex(startIndex); @7%nMTZ@&v
} P}H7WH
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publicList getItems(){ E'e#axF;
return items; Hq^sU%
} >U9*
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publicvoid setItems(List items){ @3{'!#/
this.items = items; \{n]&IjA
} j3 ~: \H
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publicint getPageSize(){ '1=t{Rw
return pageSize; L^)&"6oSa
} 7
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publicvoid setPageSize(int pageSize){ ]]+wDhxH
this.pageSize = pageSize; :a3Pnq$]E
} 5A/G?
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publicint getTotalCount(){ G7`7e@{
return totalCount; \<~[uv'
} Q5iuK#/
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publicvoid setTotalCount(int totalCount){ &M~*w~w`
if(totalCount > 0){ jGd{*4{3+
this.totalCount = totalCount; F`U%xn,
int count = totalCount / uU6+cDp
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pageSize; DPi%[CRH
if(totalCount % pageSize > 0) ;]MHU/
count++; $r9Sn
indexes = newint[count]; C2,,+* v
for(int i = 0; i < count; i++){ cxrUk$f
indexes = pageSize * 3t(nV4uDF
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i; Xf9<kbRw/
} KQ xKU?b1
}else{ Uw5z]Jck
this.totalCount = 0; &?/h#oF@\
} )`^t,x<S
} d$kGYMT"
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publicint[] getIndexes(){ h{yqNl
return indexes; z![RC59S
} Ip(
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publicvoid setIndexes(int[] indexes){ N|T%cdh:/
this.indexes = indexes; H
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} t*82^KDU
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publicint getStartIndex(){ .ev'd&l.
return startIndex; B+wSLi(
} Io{)@H"f
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publicvoid setStartIndex(int startIndex){ W j/.rG&tE
if(totalCount <= 0) ;4Y@xS2M
this.startIndex = 0; `pE~M05
elseif(startIndex >= totalCount) _NA0$bGN9
this.startIndex = indexes [(5;jUmF@
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[indexes.length - 1]; D&/(Avx.
elseif(startIndex < 0) vN-#Ej.
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this.startIndex = 0; Zk)]=<H
else{ MSoLx' <
this.startIndex = indexes I7nt<l!
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[startIndex / pageSize]; S>aN#
} ioIUIp+B~u
} ATv.3cy
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publicint getNextIndex(){ # h]m8
int nextIndex = getStartIndex() + ea=@r
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pageSize; 1 +O- g
if(nextIndex >= totalCount) OO]~\j
return getStartIndex(); &p^S6h
else N't*e Ci
return nextIndex; kz(%8qi8&
} @U_w:Q<9u
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publicint getPreviousIndex(){ 9l@VxX68M
int previousIndex = getStartIndex() - f[HhLAVGK`
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pageSize; ync2X{9D
if(previousIndex < 0) zJOjc/\
return0; [7ZFxr\:!
else 9;k_"@A6
return previousIndex; GNA:|x
} Rgw\qOb
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} d%\{,
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抽象业务类 *T*=~Y4kE
java代码: B@Ez,u5
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/** |Ma"B4
* Created on 2005-7-12 E5UI
*/ Xa.Qt.C
package com.javaeye.common.business; ji="vs=y
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import java.io.Serializable; Aj#CB.y
import java.util.List; d,CtlWp
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import org.hibernate.Criteria; DKAqQ?fS
import org.hibernate.HibernateException; "D'A7DA
import org.hibernate.Session; ce\]o^4
import org.hibernate.criterion.DetachedCriteria; p3`'i
import org.hibernate.criterion.Projections; P}KN*Hn.
import 5vj;lJKcd`
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org.springframework.orm.hibernate3.HibernateCallback; x'{L %c>L
import h!?7I=p~#
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org.springframework.orm.hibernate3.support.HibernateDaoS ;"hED:z6%
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upport; ,OsFv}v7
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import com.javaeye.common.util.PaginationSupport; ^]3Y11sI
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public abstract class AbstractManager extends 5m!FtHvm1
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HibernateDaoSupport {
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privateboolean cacheQueries = false; `$\g8Mo
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privateString queryCacheRegion; FN NEh
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publicvoid setCacheQueries(boolean UB }n=
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cacheQueries){ ^6bU4bA
this.cacheQueries = cacheQueries; 8bLA6qmM\
} cu5Yvp
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publicvoid setQueryCacheRegion(String OW-[#r
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queryCacheRegion){ abh='5H|^|
this.queryCacheRegion = .p NWd
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queryCacheRegion; $73 7oV<
} :^tw!U%y1
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publicvoid save(finalObject entity){ m_\w)
getHibernateTemplate().save(entity); SCs@Q
} T3,"g=
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publicvoid persist(finalObject entity){ 1O>wXq7q
getHibernateTemplate().save(entity); yQ-&+16^
} I
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); "Kx2k>ym
} U~n>k<`sr
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publicvoid delete(finalObject entity){ D::$YR
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getHibernateTemplate().delete(entity); RO+B/)~0<
} XW
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publicObject load(finalClass entity, #5-5N5-1
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finalSerializable id){
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return getHibernateTemplate().load 4nQk*:p(X
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(entity, id); /. GHR
} 9ot A5I^v
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publicObject get(finalClass entity, ~G|un}g=
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finalSerializable id){ bCr) 3,
return getHibernateTemplate().get _xT=AF9~o
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(entity, id); ,e{( r0
} 83~
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publicList findAll(finalClass entity){ V #["Z}
return getHibernateTemplate().find("from _PD RUJ
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" + entity.getName()); ~V&4<=r`
} gpW3zDJ
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publicList findByNamedQuery(finalString Pw
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namedQuery){ 7?a@i;E<
return getHibernateTemplate T\ZWKx*#
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().findByNamedQuery(namedQuery); ^j&'2n@9a
} /nEt%YYh;x
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publicList findByNamedQuery(finalString query, 7hwl[knyB
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finalObject parameter){ hT4u;3xE
return getHibernateTemplate gdkl,z3N3
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().findByNamedQuery(query, parameter);
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} D-\WS^#
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publicList findByNamedQuery(finalString query, #U45;idp
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finalObject[] parameters){ r2A%.bL#
return getHibernateTemplate vH/<!jtI
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().findByNamedQuery(query, parameters);
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}5
} $MD|YW5
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publicList find(finalString query){ Gh}k9-L
return getHibernateTemplate().find ,0+%ji^V
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(query); >^}nk04
} zy\p,
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publicList find(finalString query, finalObject GyI(1OAW
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parameter){ *#+e_)d
return getHibernateTemplate().find 3]xe7F'`
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(query, parameter); k$
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} v,t;!u,40
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public PaginationSupport findPageByCriteria E*V UP5E
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(final DetachedCriteria detachedCriteria){ qjcy{@ j
return findPageByCriteria 2,,zN-9mt
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); fFP>$
} VK\ Bjru9
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public PaginationSupport findPageByCriteria bB^% O^:
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(final DetachedCriteria detachedCriteria, finalint z
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startIndex){ + E8\g
return findPageByCriteria )6mx\t
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(detachedCriteria, PaginationSupport.PAGESIZE, <L|eY(:
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startIndex); :M" NB+T
} )zw}+z3st
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public PaginationSupport findPageByCriteria ly`p)6#R=
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(final DetachedCriteria detachedCriteria, finalint XE8~R5
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pageSize, :NB|r
finalint startIndex){ T&Dt;CSF
return(PaginationSupport) (I3:u-A
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getHibernateTemplate().execute(new HibernateCallback(){ lK;/97Ze
publicObject doInHibernate ERxA79
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(Session session)throws HibernateException { GE4d=;5
Criteria criteria = gM=oH
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detachedCriteria.getExecutableCriteria(session); 5G.A\`u%
int totalCount = 2`4'Y.Qf
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((Integer) criteria.setProjection(Projections.rowCount l!Q |]-.@
[s?H3yQ.
()).uniqueResult()).intValue(); A#9@OWV5f
criteria.setProjection cJ9:XWW
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(null); LF+#PnK
List items = SI_{%~k*B
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criteria.setFirstResult(startIndex).setMaxResults c-nBB
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(pageSize).list(); I!bzvPJ]xc
PaginationSupport ps = AHsp:0Ma#
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new PaginationSupport(items, totalCount, pageSize, b
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startIndex); j^A0[:2
return ps; gE8=#%1<
} S-[]z*
}, true); w
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} x7$U
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public List findAllByCriteria(final v8!
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DetachedCriteria detachedCriteria){ 2YvhzL[um
return(List) getHibernateTemplate 0Eq.l <
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().execute(new HibernateCallback(){ @+A`n21,O
publicObject doInHibernate T
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(Session session)throws HibernateException { b6=.6?H@4f
Criteria criteria = k#k !AcC
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detachedCriteria.getExecutableCriteria(session); k,0RpE
return criteria.list(); (bH*i\W
} [sG=(~BU
}, true); U(5(0r
} >O[# 661
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public int getCountByCriteria(final kJIKULf
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DetachedCriteria detachedCriteria){ `T $lTP
Integer count = (Integer) vGWX= O
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getHibernateTemplate().execute(new HibernateCallback(){ * bmdY=#7
publicObject doInHibernate `WF?87l1
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(Session session)throws HibernateException { UNLy{0tA
Criteria criteria = qA:CV(Z
. (*V|&n
detachedCriteria.getExecutableCriteria(session); K V^`
return hnS
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criteria.setProjection(Projections.rowCount .(Q3M0.D
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()).uniqueResult(); pLMki=.Ld
} '/
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}, true); NwM =
return count.intValue(); -WP_0
} Nb\4Mv`
} A" `62
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用户在web层构造查询条件detachedCriteria,和可选的 `9b/Q
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#
startIndex,调用业务bean的相应findByCriteria方法,返回一个 4VLrl8$K
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PaginationSupport的实例ps。 5{qFKo"g@,
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ps.getItems()得到已分页好的结果集 EL80f>K
ps.getIndexes()得到分页索引的数组 +g ovnx
ps.getTotalCount()得到总结果数 ~Bn#AkL
ps.getStartIndex()当前分页索引 "
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ps.getNextIndex()下一页索引 FX )g\=ov
ps.getPreviousIndex()上一页索引 yNdtq\h
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 >
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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 %b'ic
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一下代码重构了。 2H fP$.
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我把原本我的做法也提供出来供大家讨论吧: ON _uu]=
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首先,为了实现分页查询,我封装了一个Page类: ]OZZPo
java代码: "?lirOD
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/*Created on 2005-4-14*/ K^?yD
package org.flyware.util.page; .z7XYmv
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/** sxJKu
* @author Joa w(n&(5FzB<
* y.5mYQA4=[
*/ CF>k_\/Bj
publicclass Page { S(mJ;C
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/** imply if the page has previous page */ 5 +:b#B
privateboolean hasPrePage; wlBdA
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/** imply if the page has next page */ gE(QVbh(
privateboolean hasNextPage; 2#C!40j&\
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/** the number of every page */ N:[m,U9a
privateint everyPage; 3Gf^IV-
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/** the total page number */ zMt "ST.
privateint totalPage; g"(
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/** the number of current page */ ?mS798=f
privateint currentPage; 4JFi|oK0H
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/** the begin index of the records by the current Ki}PO`s
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query */ Hkg^
privateint beginIndex; 6G7B&"&
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/** The default constructor */ P1=bbMk
public Page(){ 6tI7vLmG
hE-`N,i}
} m,aJ(8G
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/** construct the page by everyPage |uV1S^!A
* @param everyPage a)PBC{I
* */ )-|A|1Uo
public Page(int everyPage){ V\%;S
this.everyPage = everyPage; ;SeDxyKG
} @)m[:n
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/** The whole constructor */ W"AWhi{h
public Page(boolean hasPrePage, boolean hasNextPage, 2:MB u5**
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int everyPage, int totalPage, fo&q/;l\
int currentPage, int beginIndex){ !0c7nzjm
this.hasPrePage = hasPrePage; >BMJA:j
this.hasNextPage = hasNextPage; :aLShxKA
this.everyPage = everyPage; gWqmK/.U.0
this.totalPage = totalPage; )Ac8'{Tq/
this.currentPage = currentPage; j#Ly!%dp
this.beginIndex = beginIndex; T,Cq;|g5E
} *pw:oTO
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/** \% !]qv
* @return u9"b,].b
* Returns the beginIndex. 'IFbD["r
*/ j\q1b:pE
publicint getBeginIndex(){ wd~e3%JM
return beginIndex; ,!F'h:
} ?+D_*'65D
Run)E*sf
/** 9 }|Bs=q
* @param beginIndex oiJa1X
* The beginIndex to set. 5*[zIKdt2
*/ b:\I*WJ
publicvoid setBeginIndex(int beginIndex){ LpaY Md;
this.beginIndex = beginIndex; p]*$m=t0r
} r.xGvo{iY
Vm_y,;/(-R
/** 8\!0yM#yK
* @return Q/\
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* Returns the currentPage. IpGq_TU
*/ %Gl, V5z&
publicint getCurrentPage(){ Y<:%_]]
return currentPage; ktU98Bk]
} n0 _:!]k^
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/** f?#:@ zcL
* @param currentPage [WXtR
* The currentPage to set. dE_BV=H{
*/ ~e{AgY)
publicvoid setCurrentPage(int currentPage){ yx3M0Qo
this.currentPage = currentPage; g~h`wv'
}
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/** YNn,{Xi
* @return ymY,*Rb
* Returns the everyPage. hZY+dHa]
*/ kWjCSC>jA
publicint getEveryPage(){ J
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return everyPage; !-2nIY!
} Ooc,R(
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/** Ag }hyIl
* @param everyPage lEQ63)Z
* The everyPage to set. zu(/c
*/ Ec8Y}C,{7<
publicvoid setEveryPage(int everyPage){ }<uD[[FLB
this.everyPage = everyPage; gmLGK1
} FgE6j;
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/** \! Os!s
* @return g v&xC 6>
* Returns the hasNextPage. +z+25qWi
*/ <\8dh(>
publicboolean getHasNextPage(){ Yt++?
return hasNextPage; ;EW]R9HCH
} ~PHAC@pU
h#^IT
/** @NlnZfMu
* @param hasNextPage QL-((dZ<
* The hasNextPage to set. 7F4$k4r<
*/ dZ9[w kn
publicvoid setHasNextPage(boolean hasNextPage){ /(BQzCP9O;
this.hasNextPage = hasNextPage; V7N8m<Tf
} {{ R/:-6?@
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/** QJTGeJ
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* @return NAZxM9
* Returns the hasPrePage. bICi'`
*/ MkC25
publicboolean getHasPrePage(){ W~.1f1)
return hasPrePage; WfhQi;r
} p
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/** 8~ .r/!wfy
* @param hasPrePage >sm<
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* The hasPrePage to set. A{: a kK
*/ `R!0uRu
publicvoid setHasPrePage(boolean hasPrePage){ r,2x?Qi
this.hasPrePage = hasPrePage; ;s3"j~5m)
} <#7}'@
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/** AVOqW0Z+y
* @return Returns the totalPage. 9TO
* 2Q|Vg*x\U
*/ 3VCyq7B^
publicint getTotalPage(){ Kk!D|NKLC
return totalPage; ~uq J@#o{
} o83HR[
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/** -qs.'o
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* @param totalPage 5L42'gJ
* The totalPage to set. W;,UhE
*/ |m"2B]"@
publicvoid setTotalPage(int totalPage){ -F4CHpua
this.totalPage = totalPage; IA&((\YC
} }{ pNasAU
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} TiCp2Rsz
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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 G-Sw`HHo
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个PageUtil,负责对Page对象进行构造: #fG!dD42
java代码: H[*.Jd
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/*Created on 2005-4-14*/ bNFX+GA/
package org.flyware.util.page; &Km?(%?
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import org.apache.commons.logging.Log; \qUmdN{FU
import org.apache.commons.logging.LogFactory; 6^mO<nB
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/** Q6MDhv,
* @author Joa !!o69
* 5A7!Xd
*/ |42E'zH&
publicclass PageUtil { _:c8YJEG{
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privatestaticfinal Log logger = LogFactory.getLog 6@wnF>'/\
6.EfM^[
(PageUtil.class); |B)e!#
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/**
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* Use the origin page to create a new page gEO#-tMjOQ
* @param page VMad ]bEf
* @param totalRecords )!|K3%9
* @return w/d9S(
*/ NX@TWBn%
publicstatic Page createPage(Page page, int RT)0I;
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totalRecords){ T_[W=9
return createPage(page.getEveryPage(), +;Q&
17$JBQ,[
page.getCurrentPage(), totalRecords); +_Fsiu_b
} 5|r3i \
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/** P;MS%32
* the basic page utils not including exception fk*JoR.o
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handler ^-~.L: }q
* @param everyPage .Ky<9h.K
* @param currentPage fT[6Cw5w`
* @param totalRecords lLmVat(
* @return page ? RB~%^c!
*/ ]B3 0d
publicstatic Page createPage(int everyPage, int MO9}Itg
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currentPage, int totalRecords){ 0Ny0#;P
everyPage = getEveryPage(everyPage); ;?=nr 5;q
currentPage = getCurrentPage(currentPage); KT{<iz_
int beginIndex = getBeginIndex(everyPage, RNRMw;cT
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currentPage); /B|#GJ\\3
int totalPage = getTotalPage(everyPage, KKGAk\X
YDi_Gl$
totalRecords); oxPOfI1%]
boolean hasNextPage = hasNextPage(currentPage, U[U$1LSS
.{5)$w>
totalPage); wCMsaW
boolean hasPrePage = hasPrePage(currentPage); Z)P x6\?+
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returnnew Page(hasPrePage, hasNextPage, Yah3I@xGy
everyPage, totalPage, @o9EX }
currentPage, 45/f}kvy
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beginIndex); `r_qvrC
} C0i: *1
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privatestaticint getEveryPage(int everyPage){ ;L(W'+
return everyPage == 0 ? 10 : everyPage; ?7^('
} .N_0rPO,Kw
/y@$|DI1
privatestaticint getCurrentPage(int currentPage){ n_$lRX5
return currentPage == 0 ? 1 : currentPage; ?tqTG2! (
} e>nRJH8pK
,EcmMI^A
privatestaticint getBeginIndex(int everyPage, int DG7FG--
(z ;=3S
currentPage){ <g>_#fz"K
return(currentPage - 1) * everyPage; 2?QIK3"v
} #Sb1oLC
v}xz`]MW<,
privatestaticint getTotalPage(int everyPage, int AJt0l|F
pSE"]N
totalRecords){ wMt?yc:X
int totalPage = 0; Y)c9]1qly
X]C-y,r[M
if(totalRecords % everyPage == 0) kul&m|
totalPage = totalRecords / everyPage; ~;UK/OZ
else lCWk)m8
totalPage = totalRecords / everyPage + 1 ; w gATfygr
^CZn<$
return totalPage; ;?= ] ffa{
} \ts:'
Va(R*38k
privatestaticboolean hasPrePage(int currentPage){ B*Hp
return currentPage == 1 ? false : true; k/?+jb
} ghbxRnU}
N(t1?R/e,
privatestaticboolean hasNextPage(int currentPage, swi|
&p8K0 |
int totalPage){ LNXhzW
return currentPage == totalPage || totalPage == MCL?J,1?r
Y_Ej-u+>{
0 ? false : true; ^q
FFF3<8
} [m3G%PO@Da
^:{l~~9iKp
jBI VZ!X
} w^G<]S{l
}`f%"Z
)w;XicT
qZKU=HM
t+m$lqm
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 aWOApXJ
JaG<.ki
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 (cNT ud$
ZzzQXfA#
做法如下: @L{HT8utK3
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +;:i,`Lmg
(d4zNYK
的信息,和一个结果集List: ^tc@bsUF
java代码: "F"G(ba^
[K&O]s<Y
[g&Q_+,j
/*Created on 2005-6-13*/ 8*>6+"w
package com.adt.bo; [7|}h/
;op+~@*!
import java.util.List; qO&:J\d
e3)rF5pp
import org.flyware.util.page.Page; C*kZ>mbc
W`6nMFg
/** VIAj]Ul
* @author Joa (zk'i13#6
*/
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publicclass Result { e/#4)@]
1i bQ'bZ
private Page page; *bmk(%g
*% Vd2jW/
private List content; ;Jv)J3y
lG fO
/** I4qzdD
* The default constructor UupQ*,dJ
*/ )c]GgPH
public Result(){
Gp@Y=mU
super(); 1MfRFv
} |
2p\M?@
sl |S9Ix
/** o)"}DeV$&
* The constructor using fields 84)S0Y8w
* j(/"}d3osm
* @param page OaU} 9&
* @param content t( p
*/ dL6sb;7R
public Result(Page page, List content){ d/P$q MD
this.page = page; I[tU}oj P
this.content = content; +vDT^|2SF
} s:I^AL5
-uy}]s5Qu
/** 1PLKcU
* @return Returns the content. [OH>NpL
*/ T_v
publicList getContent(){ tQo"$ JN}
return content; W=I%3F_C"R
} oUltr
:T%,.sH
/** n9cWvy&f
* @return Returns the page. -}4 H'%Z(i
*/ Yk?uxZ4)H
public Page getPage(){ e!eWwC9u
return page; rLh490@
} ,_\h)R_
<0v'IHlZ8
/** .N/4+[2p(
* @param content sDJ5'ul
* The content to set. Br\/7F
*/ gJvc<]W8!
public void setContent(List content){ eA{,=,v)
this.content = content; t
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} 9L!Vj J
4.H!rkMM
/** ``aoLQc`
* @param page >%Y.X38Z[
* The page to set. ,A[HYc|uy
*/ ]vKxgfF
publicvoid setPage(Page page){ .u
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this.page = page; GN=F-*2
} ~;bwfp_
} <KHB/7
O}IS{/^7
bsqoR8
+/x|P-
~X`vRSrH
2. 编写业务逻辑接口,并实现它(UserManager, f4!^0%l
8b6:n1<fn
UserManagerImpl) F^`sIrZvs
java代码: P5] cEZ n
*$ ^ME
nU`vj`K
/*Created on 2005-7-15*/ d=lZhqY
package com.adt.service; ^B1vvb
EMs$~CL4
import net.sf.hibernate.HibernateException; kIXLB!L2b^
1DZGb)OU
import org.flyware.util.page.Page; -VRu^l#
3'1O}xO
import com.adt.bo.Result; L d#
9&rn3hmP
/** Z!LzyCVl
* @author Joa Szwa2IdI.
*/ mUnnk`v
publicinterface UserManager { , aawtdt/
Ix1ec^?f
public Result listUser(Page page)throws pC#Z]_k
LNg[fF^:
HibernateException; 3b%y+?-{\u
W=F?+KgL
} I&1Mh4yu
i}+dctg/
(_<ruwV]`
:Tj,;0#/
Hej0l^
java代码: VMen:
+k8><_vr}
/SN.M6~
/*Created on 2005-7-15*/ ^z0[{1
package com.adt.service.impl; [gQ~B1O
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import java.util.List; G
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XUW~8P
import net.sf.hibernate.HibernateException; n6|}^O7
b3Y9
import org.flyware.util.page.Page; <C CEqY4
import org.flyware.util.page.PageUtil; 0{A VH/S
9dKrE_zK:
import com.adt.bo.Result; .>CqZN,^
import com.adt.dao.UserDAO; ?+`Zef.g
import com.adt.exception.ObjectNotFoundException; p(f)u]1`
import com.adt.service.UserManager; 3y 0`G8P'h
mnu7Y([2>
/** E37`g}ZS
* @author Joa D5AKOM!`
*/ nSd?P'PFg
publicclass UserManagerImpl implements UserManager { X)~JX}-L
I:mJWe
private UserDAO userDAO; ]IyC
!t;$n!7<
/** -*?a*q/#nQ
* @param userDAO The userDAO to set. (VBoZP=W
*/ u\=Nu4)Z
F
publicvoid setUserDAO(UserDAO userDAO){ 7F+w o
this.userDAO = userDAO; = @ph
} m0=CD
E\RQm}Z09
/* (non-Javadoc) n:k~\-&WJ
* @see com.adt.service.UserManager#listUser [!bTko>rSB
<niHJ*
(org.flyware.util.page.Page) '%K,A-7W
*/ 8?I(wn
public Result listUser(Page page)throws Q&n
`'
6]Z*
HibernateException, ObjectNotFoundException { E$8GXo00v
int totalRecords = userDAO.getUserCount(); gDAA>U3|$
if(totalRecords == 0)
].:S!QO
throw new ObjectNotFoundException (M5=8g%>d
>@TZYdl
("userNotExist"); !>t|vgW
page = PageUtil.createPage(page, totalRecords); #a}fI
List users = userDAO.getUserByPage(page); =A=er1~%
returnnew Result(page, users); c*1B*_08
} 3(FJ<,"D}
7%)4cHZ^$?
} 0YIvE\-
ChmPO|2F
vK2L"e
K mL
PWj
5^P)='0*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w6#hsRq[C
i]F,Y;&|
询,接下来编写UserDAO的代码: /=Q7RJ@P
3. UserDAO 和 UserDAOImpl: DZLSn Ax
java代码: s "*Cb*
<VgnrqF6:
ze,HNFg@>
/*Created on 2005-7-15*/ ,|T
package com.adt.dao; s(wbsRVP8
t;y>q
import java.util.List; .
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S ._9
import org.flyware.util.page.Page; c9f~^}jNb
$&lS7}
import net.sf.hibernate.HibernateException; h'kgL~+$
#^Sd r-
/** :ykQ[d`:|
* @author Joa +s_@964
*/ r 97 VX>
publicinterface UserDAO extends BaseDAO { O]lWaiR`
Q[8L='E
publicList getUserByName(String name)throws n*bbmG1
KvktC|~?
HibernateException; G H^i,88
qw"`NubX
publicint getUserCount()throws HibernateException; :5h&f
l'-iIbKX
publicList getUserByPage(Page page)throws ogjm6;
H={fY:%
HibernateException; T#er5WOH
lR;<6
} 1 ht4LRFi
nm\n\j~
xNq&_oY7
F/@#yQv?
N:gS]OI*
java代码: JUwP<C[
(lEWnf=2h
7{<t]wQq
/*Created on 2005-7-15*/ "&L<u0KHG
package com.adt.dao.impl; yUEUIPL
{b]WLBy
import java.util.List; d \0K3=h
_!w# {5~
import org.flyware.util.page.Page; Ak>RLD25_
=X-$kk
import net.sf.hibernate.HibernateException; 0~n=|3*P
import net.sf.hibernate.Query; CBi
V':;
Ig5J_Z^]b
import com.adt.dao.UserDAO; D2?~03c
f+L )x
/** #4d0/28b
* @author Joa ab3" ?.3m
*/ ScM2_k`D
public class UserDAOImpl extends BaseDAOHibernateImpl F"a,[i,[W
hQHV]xW
implements UserDAO { h2uO+qEsu
x ?Q;o+2v
/* (non-Javadoc) jY$|_o.4
* @see com.adt.dao.UserDAO#getUserByName -41L^Di\
.}a@OLJd
(java.lang.String) y"2#bq
*/ 5/neV&VcB
publicList getUserByName(String name)throws }Y<(1w
5_=&U-? H
HibernateException { -FE5sW
String querySentence = "FROM user in class KDHR}`
Ur5X~a\y
com.adt.po.User WHERE user.name=:name"; J,P7k$t2vv
Query query = getSession().createQuery s
g6
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(querySentence); c3K(mM:
query.setParameter("name", name); E/5w
H/
return query.list(); T[ mTA>d
} sowkxw.^Q
PJkEBdM.
/* (non-Javadoc) o7hjx hmC
* @see com.adt.dao.UserDAO#getUserCount() ))306*X\
*/ o.y4&bC14;
publicint getUserCount()throws HibernateException { F+c*v#T
int count = 0;
) VJ|
String querySentence = "SELECT count(*) FROM {e>}.R
5UjXpS
user in class com.adt.po.User"; p?6w/ n
Query query = getSession().createQuery OP``g/x)
:5C9uW#
(querySentence); GT#i Y*
count = ((Integer)query.iterate().next MF%9
:)mV-(+o
()).intValue(); t'R&$;z@b
return count; ~~wz05oRG
} Z(.p=Wg
mxDy!:@=
/* (non-Javadoc) *3.
]
* @see com.adt.dao.UserDAO#getUserByPage mlIc`GSI
=`.9 V<
(org.flyware.util.page.Page) |bB..b
*/ b\6w[52m
publicList getUserByPage(Page page)throws MUVp8!*@
<qv:7@
HibernateException { M62V NYt
String querySentence = "FROM user in class .VWH
S@T>u,t'
com.adt.po.User"; +gK7`:v4O*
Query query = getSession().createQuery dHd{9ftyF
B#sc!eLmU&
(querySentence); qmJFXnf
query.setFirstResult(page.getBeginIndex()) %o*afd
.setMaxResults(page.getEveryPage()); >W 8!YOc
return query.list(); .XYSO
} QeU>%qKT
BA
L!6
} W\FKAvS
WS2TOAya)
g[:5@fI#*
a Se.]_
vmW4a3
至此,一个完整的分页程序完成。前台的只需要调用 d+"KXt5CV
hb^e2@i;Oq
userManager.listUser(page)即可得到一个Page对象和结果集对象 @HaWd3
JWH}0+1*
的综合体,而传入的参数page对象则可以由前台传入,如果用 WYI? M
X @r5^A[9
webwork,甚至可以直接在配置文件中指定。 1~ZDHfd5
^c.b@BE
下面给出一个webwork调用示例: Q_M2!qj
java代码: *>Om3[D
>TK`s@jdSV
Y$Os&t@bu
/*Created on 2005-6-17*/
3nR|*t;
package com.adt.action.user; hLJO\=0rJz
yh lZdF
import java.util.List; *4=Fy:R]O
2lXsD;[
import org.apache.commons.logging.Log; "52wa<MVJ
import org.apache.commons.logging.LogFactory; pOw4H67
import org.flyware.util.page.Page; }]tSWVb*
{s_0[>
import com.adt.bo.Result; b!_l(2
import com.adt.service.UserService; d p_J*8
import com.opensymphony.xwork.Action; oLB pG1Va
WMl_$Fd6
/** $c f?`k
* @author Joa hq\KSFP
*/ x"_f$,:!
publicclass ListUser implementsAction{ |
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/`2VJw
privatestaticfinal Log logger = LogFactory.getLog %xWmzdn
.{)b^gE
(ListUser.class); Z&J417buk
yTbBYx9Bi
private UserService userService; ?MO'WB9+JR
`4Nc(aUr
private Page page; `4l>%S8y:
[NaU\;w\
privateList users; Gf]oRNP,N
<1_?.gSi
/* Fv e,&~
* (non-Javadoc) QDxL y aL
* d v@6wp:
* @see com.opensymphony.xwork.Action#execute() 3/]J
i^+
*/ !A!zG)Ue<
publicString execute()throwsException{ OM2|c}]ZQ
Result result = userService.listUser(page); uyAhN
page = result.getPage(); cS{ l2}E
users = result.getContent(); iHQFieZ.E
return SUCCESS; I%{U~
} KAEf4/
cF,u)+2b|6
/** D {>,2hC
* @return Returns the page. 0Wv9K~F
*/ Tz%l9aC
public Page getPage(){ ,3N8
return page; ZFrK'BvbR
} 2Uu,Vv
"B)DX*-\?
/** "fz-h
* @return Returns the users. c WK@O>
*/ \U~ggg0h
publicList getUsers(){ RTF{<,E.UX
return users; VVCCPK^<
} zIRa%%.i<
gU+BRTZ&x
/** (Grj_p6O
* @param page zse!t
* The page to set. S,Tm=} wj
*/ swlxV@NQ
publicvoid setPage(Page page){ kl2]#G(
this.page = page; x40R)Led
} Mzxz- cE
MZ0uc2L=
/** 0r+-}5aSl5
* @param users d7KeJ$xy}p
* The users to set. y0A2{'w
*/ Z AZQFr'*
publicvoid setUsers(List users){ B[b'OtH
this.users = users; i?*&1i@
} h1)p{5}H
1F[;
)@
/**
{n.g7S~
* @param userService HjnHl-
* The userService to set. T_YN^za(q
*/ azOp53zR
publicvoid setUserService(UserService userService){ YXD1B`23
this.userService = userService; Eb{TKz?
} SOP=
X-6f
} <<n8 P5pXt
KJ'MK~g
HJ_xg6.x
?A2EuvQH]
=X% D;2
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ;Oe6SNquT
hM>xe8yE
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 vuw1ycy)
?\^u},HnE|
么只需要: |vEfE{
java代码: paMw88*u
*%8,G'"r?
%tQIKjsVaY
<?xml version="1.0"?> Mc@p~5!M
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork -4GSGR'L&y
|,}QhR
1.0//EN" "http://www.opensymphony.com/xwork/xwork- eZ
]6Q
6p1TI1(
1.0.dtd"> 'OF)`5sj
/vU9eh"%
<xwork> '@pav>UPD
p4aM`PW8>=
<package name="user" extends="webwork- 5!y3=.j
W>1\f0'
interceptors"> rEddX
S93NsrBbY
<!-- The default interceptor stack name )[qY|yu
(y(V,kXwa8
--> /B}]{bcp$
<default-interceptor-ref Fb-NG.Z#
LM*9b
name="myDefaultWebStack"/> CR,
Y%0vQ
a?+) K
<action name="listUser" tK8\Ib J
E}"&?oY
class="com.adt.action.user.ListUser"> %M'"%Yn@(y
<param X}p4yR7'
BAzqdG
name="page.everyPage">10</param> ^!kvgm<{$
<result 1b_->_9
z|pH>R?:
name="success">/user/user_list.jsp</result> hpAIIgn
</action> gvsS:4N"Nq
ZE}m\|$
</package> nNQ\rO
J!yc9Q
</xwork> TxxW/f9D
Ww8C![ ,
b<:s{f"t,
@?e;Jp9
lzxn} TO}
6E_YQbdy
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 iB]kn(2C
B /Dj2
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 c~$ipX
I~q}M!v~
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %t<Y6*g
<v5toyA
EH,uX{`e
/~AwX8X
IM
+Dm
我写的一个用于分页的类,用了泛型了,hoho VN$#y4
@br%:Nt
java代码: L^ +0K}eD
75^-93
d(]LRIn~1
package com.intokr.util; 4J I;NN
!gT6So
import java.util.List; -u8@ .
?Bh}
/** ~t#'X8.)
* 用于分页的类<br> qqkZbsN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> lgnF\)
* -lAA,}&+!
* @version 0.01 rylllJz|L:
* @author cheng FWD9!M K
*/ )hQ`l d7B
public class Paginator<E> { ]%mg(&p4
privateint count = 0; // 总记录数 YY]LK%-
privateint p = 1; // 页编号 i]1[eGF
privateint num = 20; // 每页的记录数 )<3WVvB
privateList<E> results = null; // 结果 qrt+{5/t
H;$w^Tr
/** 5[Q44$a{
* 结果总数 B}?/oZW4
*/ &/7GhZRt
publicint getCount(){ F htf4
return count; 9_TZ;e
} } [75`pC~O
c)Y I3G$
publicvoid setCount(int count){ <BO|.(ys
this.count = count; ;dB=/U>3U
} ~xHr/:
w$&10
/** y XS/3_A{
* 本结果所在的页码,从1开始 if`/LJsa
* :$94y{
* @return Returns the pageNo. nQ/ha9v=n
*/ kB~: HQf
publicint getP(){ G1P m!CM=
return p; k@wT,?kD
} 9Y/c<gbY
HVk3F|]V
/** I/Vlw-
* if(p<=0) p=1 xE0+3@_>>
* _$, .NK,6
* @param p G=b`w;oL:
*/ AE<AEq
publicvoid setP(int p){ hl# 9a?
if(p <= 0) SJy? ^
p = 1; f|b|\/.=
this.p = p; \(;5YCCE
} E^|b3G6T
h,\_F#hi
/** c[j3_fn1]
* 每页记录数量 WOg_Pn9HI
*/ sN;U,{
publicint getNum(){ "@Te!.~A.
return num;
4uTYuaCNs
} +J#H9>To!
*^NC5=A(d
/** 0?sIod
* if(num<1) num=1 35c9c(A
*/ 3J[P(G>Q
publicvoid setNum(int num){ ;w@:
if(num < 1) ~xXB
!K~C
num = 1; >j$f$*x
this.num = num; s2d;601*b
} 9@:&