Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ! E<[JM
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 OcR$zlgs[v
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 mitHT :%r2
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 |s7s6k)mm
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分页支持类: y`<*U;xL
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java代码: a@_4PWzF:
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package com.javaeye.common.util; [<Mx2<8f
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import java.util.List; ($q-_m
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publicclass PaginationSupport { *>Ns_su7W
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publicfinalstaticint PAGESIZE = 30; ;v}GJ<3
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privateint pageSize = PAGESIZE; q }i]'7
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privateList items; U$O\f18
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privateint totalCount; wT6"U$cV
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privateint[] indexes = newint[0]; du<tGsy
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privateint startIndex = 0; CuaVb1r
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public PaginationSupport(List items, int R{C(K(5/
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totalCount){ m(r,Acy6
setPageSize(PAGESIZE); ak7bJ~)X=
setTotalCount(totalCount); hi_NOx
setItems(items); [`ebM,W
setStartIndex(0); l.q&D< _
} S5gyr&dm
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public PaginationSupport(List items, int u0JB\)(-/h
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totalCount, int startIndex){ QmQ=q7
setPageSize(PAGESIZE); %6|nb:Oa
setTotalCount(totalCount); 5MroNr
setItems(items); TJ10s%,V
setStartIndex(startIndex); 8H%;WU9-
} iN bIp"W
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public PaginationSupport(List items, int vNyf64)
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totalCount, int pageSize, int startIndex){ iowTLq!?
setPageSize(pageSize); Gj1&tjK
setTotalCount(totalCount); 0\X\izQ5
setItems(items); !S$:*5=&
setStartIndex(startIndex); 8v:T.o;<
} %"q9:{m
e),q0%5
publicList getItems(){ ahJ`T*)HY
return items; !8TlD-ZT/
} MUaq7B_>
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publicvoid setItems(List items){ (of#(I[m7
this.items = items; qrb[-|ie&
} T-'OwCB1q
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publicint getPageSize(){ P@,XEQRd`
return pageSize; 4-l8,@9
} .N,bIQnj
p\ Q5,eg
publicvoid setPageSize(int pageSize){ W/=.@JjI
this.pageSize = pageSize; G4Q[Th
} &agWaf1%a
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publicint getTotalCount(){ [zH:1Zhl&
return totalCount; IB(6+n,6s
} d?y4GkK
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publicvoid setTotalCount(int totalCount){ qz"}g/;?
if(totalCount > 0){ "H=6j)Cb
this.totalCount = totalCount; Jz\%%C
int count = totalCount / '*Z1tDFS
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pageSize; a4mn*,
if(totalCount % pageSize > 0) JYMiLph<
count++; I5X|(0es
indexes = newint[count]; ny]?I
for(int i = 0; i < count; i++){ :,3C 0T3r
indexes = pageSize * =-0/k;^
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i; xzdf^Ce
} XD!W: uvb
}else{ ]tim,7s
this.totalCount = 0; z{8bvuE
} >1.X*gi?-
} dph{74Dc
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publicint[] getIndexes(){ OyStq i
return indexes; )\1QJ$-M&
} KKb,d0T[
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publicvoid setIndexes(int[] indexes){ .ODU
this.indexes = indexes; ]MqMQLG0t
} OsTc5K.U~
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publicint getStartIndex(){ 7!evm;A
return startIndex; ntu5{L'8
} C>ICu*PW
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publicvoid setStartIndex(int startIndex){ j:Xq1f6a
if(totalCount <= 0) Ja|5 @
this.startIndex = 0; ;"xfOzQ
elseif(startIndex >= totalCount) \Q {m9fE
this.startIndex = indexes m~w[~flgZ
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[indexes.length - 1]; R#s)r
elseif(startIndex < 0) NyaQI<5D
this.startIndex = 0; n"h`5p5'
else{ ]>W6
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this.startIndex = indexes C+*d8_L
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[startIndex / pageSize]; EZgq ?l~5O
} cF\;_0u
} Ka'=o?'B5
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publicint getNextIndex(){ Vouvr<43o
int nextIndex = getStartIndex() + 2VPdw@"~}
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pageSize; p99]
if(nextIndex >= totalCount) $CRm3#+
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return getStartIndex(); <KJ/<0l
else ;/bewivNJ
return nextIndex; H/"-Z;0{
} 7dN*lks
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publicint getPreviousIndex(){ 'I`&Yo~c9
int previousIndex = getStartIndex() - `oAW7q)~
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pageSize; bpOYHc6,*`
if(previousIndex < 0) 'g">LQ~a+
return0; ):P?
else e-~N"
return previousIndex; _H9 MwJ
} Mhm@R@
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} .nO\kg oK
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抽象业务类 Tg7an&#
java代码: FX;QG94!
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/** #9=Vg
* Created on 2005-7-12 '%>=ZhO
*/ W4t;{b
package com.javaeye.common.business; E}%B;"b/Tj
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import java.io.Serializable; N'F77
.
import java.util.List; gBd]B03
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import org.hibernate.Criteria; *}Xf!"I#]N
import org.hibernate.HibernateException; :Oy%a'w
import org.hibernate.Session; f<-Jg
import org.hibernate.criterion.DetachedCriteria; SDL7<ZaE
import org.hibernate.criterion.Projections; Eu0akqZ
import We)xB
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org.springframework.orm.hibernate3.HibernateCallback; PG2: ~$L0
import (|F*vP'
)"qa kT
org.springframework.orm.hibernate3.support.HibernateDaoS c& <Fr[AK
dLH(D: `
upport; Upx G@b
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import com.javaeye.common.util.PaginationSupport; u+dLaVlLJ
} FE>|1
public abstract class AbstractManager extends k3~}7]O)
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HibernateDaoSupport { Fzm*Pz3
},uF4M.K
privateboolean cacheQueries = false; 1eA7>$w}[
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privateString queryCacheRegion; S Q@y;|(
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publicvoid setCacheQueries(boolean }#3V+X
B)$| vK=
cacheQueries){ #HYr0Tw6`
this.cacheQueries = cacheQueries; 2{D{sa
} 85>05?
PYQ;``~x
publicvoid setQueryCacheRegion(String W=lyIb{?^0
mD/9J5:
queryCacheRegion){ 88Ey12$
this.queryCacheRegion = 6e (Qwt
8<5]\X
queryCacheRegion; rW<KKGsRWQ
} `Nv=B1
w}L]X1#sF
publicvoid save(finalObject entity){ %W'v}p
getHibernateTemplate().save(entity); ^9m\=5d
} $': E\*ICb
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publicvoid persist(finalObject entity){ %) /s; Q,
getHibernateTemplate().save(entity); t9nqu!);
} [v7F1@6b
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publicvoid update(finalObject entity){ -M~8{buxv
getHibernateTemplate().update(entity); 9 *xR6
} czA5n
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publicvoid delete(finalObject entity){ >~#yu&*D
getHibernateTemplate().delete(entity); PvzcEV
} 9Q.rMs>qj
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publicObject load(finalClass entity, \@Ts+7%
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finalSerializable id){ -] LY,M
return getHibernateTemplate().load ?fiIwF)
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(entity, id); z-BXd
} \j+1V1t9
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publicObject get(finalClass entity, 2SD`OABf#
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finalSerializable id){ ,bXe<L)
return getHibernateTemplate().get }bs+-K
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(entity, id); Az9?Ra;U
} Gp1?iX?ml
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publicList findAll(finalClass entity){ I*o()
return getHibernateTemplate().find("from 8H;t_B
>/g#lS 5
" + entity.getName()); +"x,x
} Z.c'Hs+;
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publicList findByNamedQuery(finalString 6rh5h:
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namedQuery){ A]<y:^2])C
return getHibernateTemplate f}aL-N~
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().findByNamedQuery(namedQuery); {^
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} 6,o~\8ia
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publicList findByNamedQuery(finalString query, r/4``shg
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finalObject parameter){ |"?M 1*g
return getHibernateTemplate FI[A[*fi
3Q"<<pi!~
().findByNamedQuery(query, parameter); lun#^ J
} 1uG"f<TsR
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publicList findByNamedQuery(finalString query, 0+iu(VbF
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finalObject[] parameters){ 4^:\0UF
return getHibernateTemplate 0bz'&
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().findByNamedQuery(query, parameters); 7[w,:9& }
} TBs|r#
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publicList find(finalString query){ :a^t3s
return getHibernateTemplate().find <_h~w}
b+,';bW
(query); Mxe}B'
} 5G::wuxk
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publicList find(finalString query, finalObject E4xj?m^(y=
|P[w==AAf
parameter){ .)RzT9sg
return getHibernateTemplate().find Mc=$/ o
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(query, parameter); uPhK3nCGo
} t,,k
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public PaginationSupport findPageByCriteria -!q:p&c
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(final DetachedCriteria detachedCriteria){ V\{clJ\U
return findPageByCriteria ~s%
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ADS9DiX/
} OSlvwH%(EE
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public PaginationSupport findPageByCriteria jB`,u|FG
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(final DetachedCriteria detachedCriteria, finalint ;LcVr13J/
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startIndex){ &]8P1{
return findPageByCriteria 9zZr^{lUl
,.rs(5.z8/
(detachedCriteria, PaginationSupport.PAGESIZE, !LggIk1
'L
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startIndex); lm!.W5-l
} qo p^;~
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public PaginationSupport findPageByCriteria D6%J\C13`
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(final DetachedCriteria detachedCriteria, finalint yXz*5W_0D
P=7zs;k
pageSize, @$lG@I,[
finalint startIndex){ ?>hPO73{
return(PaginationSupport) ~kShq%
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getHibernateTemplate().execute(new HibernateCallback(){ 6;u$&&c(
publicObject doInHibernate 3
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(Session session)throws HibernateException { Ge2q%
Criteria criteria = 6""G,"B
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{
detachedCriteria.getExecutableCriteria(session); ]j'p :v
int totalCount = T@G?t0
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((Integer) criteria.setProjection(Projections.rowCount w,w{/T+B
j:5=s%S
()).uniqueResult()).intValue(); }3o|EXx=
criteria.setProjection :axRoRg
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(null); PfreAEv,
List items = Nd`%5%'::
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criteria.setFirstResult(startIndex).setMaxResults 9
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-}=i 04^
(pageSize).list(); ,u!*2cWN
PaginationSupport ps = G;&-\0>W
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new PaginationSupport(items, totalCount, pageSize, y<HO:kZ8`
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startIndex); K&nE_.kbl
return ps; v 0
}@
} n1JRDw"e$$
}, true); Ey_" ~OB
} ZYI{i?Te#
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public List findAllByCriteria(final %70~M_
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DetachedCriteria detachedCriteria){ TatpXN\
return(List) getHibernateTemplate }2<r,
Anscr
().execute(new HibernateCallback(){ [K9'<Qnu
publicObject doInHibernate KAC6Snu1
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(Session session)throws HibernateException { n1~o1
Criteria criteria = xgpi-l
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detachedCriteria.getExecutableCriteria(session); 3^R&:|,
return criteria.list(); x$IX5:E#e
} bLe<G
}, true); ,8:(OB|a
} >_o}
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public int getCountByCriteria(final U'8bdsF_
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DetachedCriteria detachedCriteria){ ~Q?a|mV,
Integer count = (Integer) WOQP$D9
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getHibernateTemplate().execute(new HibernateCallback(){ hCCiD9gz
publicObject doInHibernate X}tVmO?
vWRju*Z&
(Session session)throws HibernateException { ]F; f`o
Criteria criteria = o=21|z
qp/v^$EA
detachedCriteria.getExecutableCriteria(session); BnCbon)
return .C&ktU4
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criteria.setProjection(Projections.rowCount *"D3E7AO
5"HVBfFk
()).uniqueResult(); ?*E'^~,H)
} ]Bm/eRy"
}, true); ?mWw@6G,
return count.intValue(); q8^^H$<Db
} %F!1
} #>%X_o-o23
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用户在web层构造查询条件detachedCriteria,和可选的 :Qumb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 pV20oSJNt
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PaginationSupport的实例ps。 --HF8_8;'
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ps.getItems()得到已分页好的结果集 _h X]%
ps.getIndexes()得到分页索引的数组 ;cPy1
ps.getTotalCount()得到总结果数 >)spqu]
ps.getStartIndex()当前分页索引 AI,(z;{P
ps.getNextIndex()下一页索引 Sg6"WV{<
ps.getPreviousIndex()上一页索引 V#cqRE3XNi
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 t*>R`,j
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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 7qj9&bEy
t: #6sF
一下代码重构了。 HRiL.DS
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我把原本我的做法也提供出来供大家讨论吧: 7RUofcax
ZJwrLV
首先,为了实现分页查询,我封装了一个Page类: m9" n4a|:
java代码:
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/*Created on 2005-4-14*/ VJdIHsI
package org.flyware.util.page; ZCB_
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/**
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* @author Joa CAcS~ "
* MxY/`9>E|+
*/ u>TZt]h8
publicclass Page { -[6z 1"*
*d"DA[(
/** imply if the page has previous page */ e pU:
privateboolean hasPrePage; ))&;}2{
m|=H#
/** imply if the page has next page */ q{t*34R
privateboolean hasNextPage; NX|v=
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/** the number of every page */ [ {
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privateint everyPage; ADpmvW f?
du)~kU>l
/** the total page number */ .G+Pe'4a
privateint totalPage; M@?xa/E64
w:?oTuw
/** the number of current page */ :,J}z~I,lB
privateint currentPage; agjv{
[1F*bI
/** the begin index of the records by the current 1RK=,Wx
?r?jl;A&
query */ UN zlN
privateint beginIndex; -5T=:2M
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/** The default constructor */ B<~ NS)w
public Page(){ (;q\}u
P#fM:z@[
} rFC" Jx
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/** construct the page by everyPage J41G&$j(
* @param everyPage 9nH?l{As
* */ d)pV;6%[$q
public Page(int everyPage){ QF&W`c
this.everyPage = everyPage; ^NX"sM0g
} W2z*91$
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/** The whole constructor */ zOGU8Wg
public Page(boolean hasPrePage, boolean hasNextPage, ^_ kJKM,
4H|(c[K;
xj[(P$,P
int everyPage, int totalPage, xia |+
int currentPage, int beginIndex){ ap{2$k ,
this.hasPrePage = hasPrePage; O9g{+e`
this.hasNextPage = hasNextPage; :%sXO
this.everyPage = everyPage; FIbp"~
this.totalPage = totalPage; TpHfS]W-P
this.currentPage = currentPage; s%2v3eb
this.beginIndex = beginIndex; L3n_ 5|
} *&d<yJM`b
(ZY@$''
/** V^\8BVw
* @return [-)r5Dsdq
* Returns the beginIndex. i} N8(B(
*/ HO[wTB|D]
publicint getBeginIndex(){ 1}tbH[
return beginIndex; om]4BRe
} <0S,Q+&
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/** i:Zm*+Gi
* @param beginIndex $2u 'N:o
* The beginIndex to set. WdnIp!
*/ :"l-KQ0
publicvoid setBeginIndex(int beginIndex){ \#rIQOPl?
this.beginIndex = beginIndex; Vo7dAHHL
} %s&ChM?8F
>-O/U5<!
/** ]ix!tb.Q
* @return @"o@}9=d
* Returns the currentPage. kWNV%RlSx
*/ &[At`Nw71
publicint getCurrentPage(){ 3 q`)*
return currentPage; SL,p36N
} 2e|N@j
&
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/** Ton94:9bZ
* @param currentPage 3;8!rNN
* The currentPage to set. ZvUCI8
*/ #rY sj-2
publicvoid setCurrentPage(int currentPage){ &`fhEN
this.currentPage = currentPage; {&"L~>/o
} QjC22lW-
eQVZO>)P1+
/** iC*F
* @return [xT:]Pw}
* Returns the everyPage. EZYBeqv
*/ 9
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publicint getEveryPage(){ 0d3+0EN{
return everyPage; gd0Vp Xf'
} |,aG%MTL
.cR
-V`
/** EaWS. eK
* @param everyPage ;/0 Q1-
* The everyPage to set. !o>H1#2l
*/ /[9t`
publicvoid setEveryPage(int everyPage){ e5OsIVtjr
this.everyPage = everyPage; sg8/#_S1i
} /"?HZ% W
oX4q`rt
/** ~`D|IWMDq
* @return Z(ZiFPx2Z
* Returns the hasNextPage. ?]rPRV
*/ VOr 1
publicboolean getHasNextPage(){ PC qZNBN
return hasNextPage; (D
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} $-&BB(-{E&
#_B-4sm
/** [y0O{,lI
* @param hasNextPage HBY.DCN[Z
* The hasNextPage to set. 2 QNNp:`6
*/ i@][rdhT
publicvoid setHasNextPage(boolean hasNextPage){ q|%(3,)ig
this.hasNextPage = hasNextPage; w ~ dk#=
} .)+hH y
Z lHDi!T
/** 0Hs|*:Y1D
* @return S=xA[%5
* Returns the hasPrePage. XUF\r]B,9
*/ ^0#;YOk
publicboolean getHasPrePage(){ z`Hy'{1
return hasPrePage; rS0DSGDq
} VqE~c
Nk[2nyeO>
/** c,Euv>*`
* @param hasPrePage Q.Aw2
* The hasPrePage to set. <jS~ WI@
*/ 5~.ZlGd
publicvoid setHasPrePage(boolean hasPrePage){ unJ R=~E
this.hasPrePage = hasPrePage; U#n#7G6fRp
} KK,Z"){
QaGlR`Y
/** &wU'p-V
* @return Returns the totalPage. 8_&CT
:u>
* _Cw:J|l.
*/ zd_HxYrN
publicint getTotalPage(){ X]loJoM9
return totalPage; | ea~'N1
} }dxDtqb
Bk}><H
/** dtPoo\@
* @param totalPage "Pl9 nE
* The totalPage to set. >3gi yeJ
*/ GdVhK:<>
publicvoid setTotalPage(int totalPage){ j,d*?'X
this.totalPage = totalPage; X1tXqHJF}
} t |W)
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} u4"SH(
Uu 7dSU
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za'6Y*CGgX
hCYQGx0
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 E(Rh#+]Y5
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个PageUtil,负责对Page对象进行构造: 7DKz;o
java代码: )s9',4$eK<
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@FN*TJ
/*Created on 2005-4-14*/ ~dHM4lGY
package org.flyware.util.page; |BZDhd9<{
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import org.apache.commons.logging.Log; ^Cv^yTj;&
import org.apache.commons.logging.LogFactory; ]l~Vi_c
Sb".]>^
/** `d 2,*KR
* @author Joa ki;UY~
* dP]1tAO,y
*/ { m8+Wju}
publicclass PageUtil { K={qU[_O
ZAuWx@}
privatestaticfinal Log logger = LogFactory.getLog qpJ{2Q
t!1$$e?`r
(PageUtil.class); 7*w VI+
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/** "Dy'Kd%,%/
* Use the origin page to create a new page Z.i{i^/#(
* @param page %b?$@H-Re
* @param totalRecords ^")F7`PF
* @return ]=73-ywn]
*/ d {2
publicstatic Page createPage(Page page, int ~e@>zoM'^
@OV-KT[>
totalRecords){ k;dXOn
return createPage(page.getEveryPage(), z5Qs@dG
XA_FOw!cX
page.getCurrentPage(), totalRecords); +~nzii3
} _U|7'^ |
Xj+q~4{|vt
/** wyxGe<1
* the basic page utils not including exception :`vP}I ^
6qo^2
handler >cL{Ya}Rz
* @param everyPage DZ
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* @param currentPage s]27l3)B
* @param totalRecords fR-C0"c
* @return page W</n=D<,I
*/ t j Vh^
publicstatic Page createPage(int everyPage, int VyG4(Xva
Z<b"`ty.
currentPage, int totalRecords){ 1U\$iy8}
everyPage = getEveryPage(everyPage); G&eP5'B4i
currentPage = getCurrentPage(currentPage); qu6DQ@
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int beginIndex = getBeginIndex(everyPage, $trAC@3O@
r!N]$lB
currentPage); w-N1.^
int totalPage = getTotalPage(everyPage, @LD6:gy
[LM^),J?
totalRecords); \'?#i@O
boolean hasNextPage = hasNextPage(currentPage, oh#N
0
0X
;/AG@$)
totalPage); gd@p|PsS^
boolean hasPrePage = hasPrePage(currentPage); ;SKh
#6S75{rnW"
returnnew Page(hasPrePage, hasNextPage, o5Rz%k#h
everyPage, totalPage, 0>6DSQq~t(
currentPage, \[wCp*;1}
mZ0J!QYk
beginIndex); pF=g||gS
} H ;@!?I
y@ek=fT%4
privatestaticint getEveryPage(int everyPage){ \6j^kY=
return everyPage == 0 ? 10 : everyPage; "u')g&
} \Mx
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r@)A
k
privatestaticint getCurrentPage(int currentPage){ QBE@(2G}C
return currentPage == 0 ? 1 : currentPage; =
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} `kBnSi o~
Ln#a<Rx.E7
privatestaticint getBeginIndex(int everyPage, int ,i`h
x,
Rg
W,hWOO
currentPage){ vrl[BPI
return(currentPage - 1) * everyPage; *ftC_v@p5
} h!]"R<QQdu
X.|Ygx
privatestaticint getTotalPage(int everyPage, int T>]sQPg
t)1phg4H)
totalRecords){ JSMPyj
int totalPage = 0; h%#_~IA:|
4,eQW[;kk
if(totalRecords % everyPage == 0) _ptP[SV^j
totalPage = totalRecords / everyPage; u"VS* hSH
else K!8zwb=fq
totalPage = totalRecords / everyPage + 1 ; Aa(<L$e!`
m24v@?*
return totalPage; +GNWF%
zN
} $G?(OWI}l`
%|Hp Bs#'
privatestaticboolean hasPrePage(int currentPage){ ~\_T5/I%
return currentPage == 1 ? false : true; .{rbw9
} H"YL
k
?s{C//
privatestaticboolean hasNextPage(int currentPage, } ~enEZ
x6yW:tUG5
int totalPage){ }N3`gCy9eN
return currentPage == totalPage || totalPage == Etnb3<^[t
?g}kb
0 ? false : true; >2-F2E,
} eO4)|tW
!ng\`
|8?
j]> uZalr
} P\B3
y+)
LdTIR]
,?b78_,2
/mbCP>bcG
5j[#'3TSU
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Sb<\-O14"
_-a|VTM
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 QPg2Y<2
U~QMR-bz
做法如下: 23E0~O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 @W9H9PWv&
O3_B<Em
的信息,和一个结果集List: co]Gmg6p
java代码: Va9q`XbyO
V<0$xV1b|=
d(l|hmj4j9
/*Created on 2005-6-13*/ ofwQ:0@
package com.adt.bo; qC
j*>D
*wUdC
import java.util.List; @l,{x|00
_g6wQdxT
import org.flyware.util.page.Page; |zMqJ.qu
0BC`iql5
/** zzf7S%1I
* @author Joa Ow3a0cF[9
*/ ,C!n}+27
publicclass Result { kMS5h~D[
0eA5zFU7
private Page page; b>=7B6 Aw
m3?e]nL4W
private List content; 8t``NZ[
%|?1B$s0
/** !GN Xt4D
* The default constructor 1o#vhk/"+
*/ zz3 r<?#5
public Result(){ Jk*QcEE=
super(); Ao*FcrXN
} \dNhzd#
"t+r+ipf])
/** cdp{W
* The constructor using fields w b+<a
* W?PWJkIw
* @param page 0WS|~?OR@
* @param content BGpk&.J
*/ uHrb:X!q
public Result(Page page, List content){ @U7Dunu*f
this.page = page; +E#PJ_H=F8
this.content = content; z[biK|YL
} $B ?? Ip?P
Y UZKle
/** Qdm(q:w
* @return Returns the content. G1r V<,#m
*/ x vJ^@w'
publicList getContent(){ H
/%}R
return content; >W~=]&7{s4
} J" wKR y
{e6KJ@H6
/** &G=0
* @return Returns the page. =BW9/fG
*/ GWh|FEqUbf
public Page getPage(){ 9TW8o}k`
return page; a^/K?lAB8
} a(!3Afi
m9b(3
/** o_3*;}k8
* @param content s?+fPOF
* The content to set. f@*>P_t
*/ u7~mnl
public void setContent(List content){ cP('@K=p
this.content = content; M%;"c?g
} TRCI\
.J:;_4x
/** #}j]XWy
* @param page Av[Ud
*~
* The page to set. X=#It&m%s
*/ AA_@\:w^
publicvoid setPage(Page page){ T8mY#^sW_
this.page = page; 'W+i[Ep5Q
} G)4SWu0<t
} m/" J
s
\3:
L Nt
6.UKB<sV
ip674'bq7R
jB/V{Y#y9@
2. 编写业务逻辑接口,并实现它(UserManager, 6*V8k%H
}2mI*"%)\u
UserManagerImpl) lkN'uZ
java代码: E7gL~4I
,-!2 5G
^Bn1;
/*Created on 2005-7-15*/ =lm nzu<
package com.adt.service; ktWZBQY
PMsC*U,oe
import net.sf.hibernate.HibernateException; "bi !=
8}9Ob~on
import org.flyware.util.page.Page; Djyp3uUA/
J[MVE4&
import com.adt.bo.Result; :=Nb=&lst
uh1S
7!^
/** a6P!Wzb
* @author Joa KDX$.$#
*/ }*Dd/'2+1
publicinterface UserManager { c0SX]4}
G
n'Bmz
public Result listUser(Page page)throws +L n M\n
m.Twgin
HibernateException; %L28$c3p
4"z;CGE7
} r
/^'Xj'(
D|"sE>
@N]5&4NL
V3 qT<}y|
>Rr!rtc'x
java代码: qZ233pc
vD_u[j]
{q})kO
/*Created on 2005-7-15*/ i5Eeg`NMl
package com.adt.service.impl; F],TG&>5
d`UF0T
import java.util.List; *J.c $1#h
e7h\(`J0lj
import net.sf.hibernate.HibernateException; H a90
TdNsyr}JG
import org.flyware.util.page.Page; W.z$a.<(rF
import org.flyware.util.page.PageUtil; fHLFeSfH
7Onk!NH
import com.adt.bo.Result; f<^ScFVR
import com.adt.dao.UserDAO; #0jSZ g^,"
import com.adt.exception.ObjectNotFoundException; xP42xv9U
import com.adt.service.UserManager; 2NyUmJ42
EQ6l:[
/** icU"Vyu
* @author Joa _ \_3s
*/ cgzy0$8dj\
publicclass UserManagerImpl implements UserManager { L,O>6~9:^1
)Kxs@F
private UserDAO userDAO; j1W
bD7*8
33O)k*g
/** @Ap@m6K?q
* @param userDAO The userDAO to set. +yt 6.L
*/ 7xz#D4[
publicvoid setUserDAO(UserDAO userDAO){ |}:e+?{o
this.userDAO = userDAO; Zp^)_ 0
} LH bZjZ2
%f_FGh
/* (non-Javadoc) tP&{ J^G
* @see com.adt.service.UserManager#listUser 7 FEzak'
)iT.A
(org.flyware.util.page.Page) o`oRG)QC
*/ SnH:(tO[X
public Result listUser(Page page)throws 5%EaX?0h+
/\6}SG;
HibernateException, ObjectNotFoundException { Hf;RIl2F
int totalRecords = userDAO.getUserCount(); 5T7_[{
if(totalRecords == 0)
$:qI&)/
throw new ObjectNotFoundException
11PLH0
t)YFTO"Jj
("userNotExist"); PY[Sz=[
page = PageUtil.createPage(page, totalRecords); /,=Wy"0TJ
List users = userDAO.getUserByPage(page); e!TG< (S
returnnew Result(page, users); =ltbS f7
} TXA. 6e
H't `Q&]a
} ~3LhcU-
c& 9+/JYMo
[3 Wsc`Q
K!pxDW}
~vO'p
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ZJ;wRd@
-HO6K)ur
询,接下来编写UserDAO的代码: @hE7r-}]
3. UserDAO 和 UserDAOImpl: kxcgOjrmI
java代码: E!:.G+SEl
#-l!`\@
`HE>%=]b
/*Created on 2005-7-15*/ jB}_Slh1j
package com.adt.dao; :_W0Af09
Tb>IHoil
import java.util.List; 8:;u
v7p
k#{lt-a/
import org.flyware.util.page.Page; 9\\@I
=;
~nLkn#Z
import net.sf.hibernate.HibernateException; T2c_vY
.Y=Z!Q
/** K8e4ax
* @author Joa ]L5Z=.z&
*/ AJJ%gxqGq
publicinterface UserDAO extends BaseDAO { >FK)p
,Y78Q
publicList getUserByName(String name)throws w*|= k~z
Sn{aHH
HibernateException; n_e}>1_
mtiO7w"M\7
publicint getUserCount()throws HibernateException; 'lQ
3j[w
-Lfp
publicList getUserByPage(Page page)throws #n6FQ$l8m
*y":@T
HibernateException; %[+a[/
4GmSG,]
} 4]|9!=\
~ wJ3AqNC?
wj5qQ]WC
=R"Eb1
S)Ub/`f{s
java代码: b |o`Q7Hj
yg-L^`t+B5
%zIl_/s
/*Created on 2005-7-15*/ S'v V"
package com.adt.dao.impl; y \mutm
a:(: :m
import java.util.List; "(HA9:
|wyJh"4!
import org.flyware.util.page.Page; lEVQA*u[
q9g[+*9]$
import net.sf.hibernate.HibernateException; }uV?
import net.sf.hibernate.Query; 0C"PC:h5
7Y_fF1-wY
import com.adt.dao.UserDAO; m=("N
Sm*Jysy`
/** HL}sqcp
* @author Joa o[Wagg.%
*/ G{&yzHAuae
public class UserDAOImpl extends BaseDAOHibernateImpl Mo?t[]L
D-2v>l_
implements UserDAO { h1G*y
Cnc\sMDJ\B
/* (non-Javadoc) <?=mLOo=
* @see com.adt.dao.UserDAO#getUserByName
01UR
tNi%}~Z
(java.lang.String) \r1kbf7?
*/ GtAJ#[5w
publicList getUserByName(String name)throws D~i@. k
iA^+/Lt
HibernateException { 8-y: == C
String querySentence = "FROM user in class K@$L~G
qD=m{O8%_
com.adt.po.User WHERE user.name=:name"; 'o#J>a~!9L
Query query = getSession().createQuery AD!<%h:
+ 8K1]'t$
(querySentence); ac+k 5K+
query.setParameter("name", name); I[cV"BDa
return query.list(); nDoiG#N0
} }?Yr>ZRi
N8MlT \+r
/* (non-Javadoc) #?b^B~ #
* @see com.adt.dao.UserDAO#getUserCount() '%]@a7w
*/ C&CsI] @g
publicint getUserCount()throws HibernateException { |)72E[lL
int count = 0; 7gdU9c/q,
String querySentence = "SELECT count(*) FROM KWn1 %oGJ
&xiDG=I#
user in class com.adt.po.User"; DESViQM
Query query = getSession().createQuery LGo@F;!n
+~i+k~{`H
(querySentence); 0:B^
count = ((Integer)query.iterate().next ~y-vKCp|
y
T1Qep
()).intValue(); /i~^LITH
return count; lu@>?,<
} SJ WP8+
'Kso@St`o
/* (non-Javadoc) E23 Yk?"
* @see com.adt.dao.UserDAO#getUserByPage >fZ/09&3
\w0b"p
(org.flyware.util.page.Page) wMPw/a;
*/ X\$W'^ np
publicList getUserByPage(Page page)throws ;KZtW
BHJ'[{U*w
HibernateException { sY;gh`4h
String querySentence = "FROM user in class l
SVW}t
@BHS5^|
com.adt.po.User";
Sfoy8<j
Query query = getSession().createQuery rM
>V=|9,
F#}1{$)%
/
(querySentence); DP6{HR$L
query.setFirstResult(page.getBeginIndex()) J PzQBc5e
.setMaxResults(page.getEveryPage()); s
eZ<52f2
return query.list(); *_).UAP.
} ch,Zk )y:_
D`~{[cv)\
} |C)UZ4A/p
p,AD!~n`
EDidg"0p
=[)N6XV 3
y!6:
至此,一个完整的分页程序完成。前台的只需要调用 ,M/#Q6P0}
va/4q+1GfH
userManager.listUser(page)即可得到一个Page对象和结果集对象 MkNURy>n&
`2(R}zUHN
的综合体,而传入的参数page对象则可以由前台传入,如果用 D"] [&m
`2mbF^-4
webwork,甚至可以直接在配置文件中指定。 ZAM+4#@
+S5_J&~
下面给出一个webwork调用示例: M}oFn}-T9a
java代码: gM5p1?E
X,Q=n2X?3
tId !C
/*Created on 2005-6-17*/ IL6f~!
package com.adt.action.user; "k1Tsd-
=@jMx^A"
import java.util.List; %`\_l
4@mXtA
import org.apache.commons.logging.Log; ;`PkmAg
import org.apache.commons.logging.LogFactory; ,nChwEn
import org.flyware.util.page.Page; 7+!7]'V
$-9@ /%Y
import com.adt.bo.Result; S.F=$z.%
import com.adt.service.UserService; (jE:Q2"
import com.opensymphony.xwork.Action; wh m tEY
vsz^B
:j
/** b;{"lJ:+Z
* @author Joa ?6YUb;
*/ 'iISbOM
publicclass ListUser implementsAction{ 6j"I5,-~!
hC,-9c
privatestaticfinal Log logger = LogFactory.getLog WKIiJ{@L
.SV3<)
(ListUser.class); X@AkA9'fq
7@cvy?
v{
private UserService userService; \y )4`A
PLD'Q,R
private Page page; b}L,kT
%FWfiFV|<
privateList users; g&F<Uv#mZ
A{Htpm ~
/* )>M@hIV5>
* (non-Javadoc) '-]BSU
* qddT9U|8~
* @see com.opensymphony.xwork.Action#execute() 8!%"/*P$
*/ ~W *j^+T"
publicString execute()throwsException{ &aAo:pj
Result result = userService.listUser(page); -%V-'X5
page = result.getPage(); U9fF;[g
users = result.getContent(); 4x{ti5Y0
return SUCCESS; 7C?mD75j
} ODvpMt:+
PM<LR?PLc
/** ApJf4D<V
* @return Returns the page. xOyL2
*/ P5xmLefng
public Page getPage(){ XhD fI
&
return page; *n_4Rr
} 8Gg/M%wq9U
ZUJOBjb`
K
/** R|$`MX}'z
* @return Returns the users. Eg29|)qsz
*/ :aqskeT
publicList getUsers(){ EM
w(%}8w
return users; Ahbu >LPk
} X|1YGZJ
!K~$-jlT
/** yj+b/9My
* @param page gI5nWEM0{
* The page to set. Q!e0Vb
*/ 49fq6ZhO
publicvoid setPage(Page page){
<m:wuNEM
this.page = page; M*6@1.n
} NP'DuzC
{bW3%iU
/** Dj.+5f'
* @param users "s<lLgi
* The users to set. []3}(8yxGb
*/ v!h-h&p O7
publicvoid setUsers(List users){ y/6LMAI
this.users = users; |B$\3,
} 4^ 6L ])y
KmOa^vY1.T
/** xLK0~|_#!
* @param userService 'R'a/ZR`B7
* The userService to set. 9:w,@Phe
*/ TC{Qu;`H+U
publicvoid setUserService(UserService userService){ FF!g9>
this.userService = userService; qML*Kwg
} .%Q Ea_\
} ,4W((OQ^
$[CA#AXE
5@%-=87S
y+afUJT
/(pChY>
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, }/0dfes
yZ0ZP
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ~RAH -]
7O^ S.(
么只需要: Bic {
H
java代码: 0%NI-
Zyo
`2+e\%f/0
|6^ K
<?xml version="1.0"?> " z'!il#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork BQ0\+
R>&/n/l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- M
F: Eu
0w. _}Cz
1.0.dtd"> xumv I{
"1Aus
<xwork> 8mLU ~P
|
4PM`hc
<package name="user" extends="webwork- `3oP^#
:?k=Yr
interceptors"> mJR
T+SZ
@\}36y
<!-- The default interceptor stack name M)^9e?
yLOLv6g~e
--> +aqo8'a
<default-interceptor-ref Kp8T;&<Iay
s2=X>,kz?
name="myDefaultWebStack"/> S9oGf
]X|G+[Ujv
<action name="listUser" "]Td^Nxi
!PIdw~YC
class="com.adt.action.user.ListUser"> <j3HT"^[D
<param +qf{ '|H
hO@3-SRa,k
name="page.everyPage">10</param> yv4PK*
<result KZfRiCZ
0*x?
name="success">/user/user_list.jsp</result> 7b2<,
.E
</action> `_^=OOn
VW`=9T5%@
</package> AI; =k
F
&}V65
</xwork> ~U+'3.Wo
0|;=mYa4M
8:fiO|~%
K.m[S[cy
U~t(YT
cpnwx1q@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ]bweQw@i
!;Nh7vG
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 oH"N>@ Vl
0+pJv0u
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 .9Fm>e+!C
ZE`{J=,
c iX2G
P,_E 4y
1hi j4m$b
我写的一个用于分页的类,用了泛型了,hoho a"aV&t
l:f
sZO4
java代码: ayp}TYh*
cyNLeg+O*
mu sxX58%
package com.intokr.util; Zh^w)}(W
64fG,b
import java.util.List; `Cxe`w4
ow[qpP[
/** p]4
sN
* 用于分页的类<br> 3IFU{0a`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #mYxO
* =YIQ
_,{u
* @version 0.01 Hp!F?J7sx
* @author cheng P7-3Vf_L
*/ IhLfuyFWu
public class Paginator<E> { 0aWb s$FyU
privateint count = 0; // 总记录数 Q,`kfxA`O
privateint p = 1; // 页编号 `f]O
privateint num = 20; // 每页的记录数 CI{x/ e^(
privateList<E> results = null; // 结果 GNOC5 E$I
O]lfs>>x
/** <@u6*]
* 结果总数 >k|[U[@
*/ Dy!fwYPA/{
publicint getCount(){ ,RQ-w2j?
return count; >B7OTGw
} PK"
C+o;:
'zK*?= ^jk
publicvoid setCount(int count){ i;Y^}2
this.count = count; 7i.aZ2a%
} sSUd;BYf
aDuanGC/V
/** W( YJz#]6_
* 本结果所在的页码,从1开始 "#jKk6{I0
*
N=9lA0y+
* @return Returns the pageNo. Cq~Ir*"
*/ I]X<L2
publicint getP(){ kZQ;\QL1}
return p; cDg27xOUi
} ny=iAZM>q
-;}Wm[
/** x}d\%*B
* if(p<=0) p=1 rej[G!
* t
,$)PV
* @param p *Y Ox`z!R
*/ \`C3;}o:"P
publicvoid setP(int p){ Ek3O{<
if(p <= 0) x5ia<V>=d
p = 1; 2+PIZ6=hN
this.p = p; 0P(}e[~Z
} M_K&x-H0
]mSVjF3l
/** ?L^ Gu ]y
* 每页记录数量 {Hu0
*/ >pKI'
publicint getNum(){ Sf9+TW
return num; #x21e }Li
} K-ebAaiC
STe;Sr&p
/** AI2CfH#:C
* if(num<1) num=1 V 6F,X`7
*/ } qTvUs
publicvoid setNum(int num){ /hQ!dU.+
if(num < 1) X}$S|1CjO
num = 1; Dg`W{oj
this.num = num; Cb.Aw!
} fJuJ#MX{:
JFfx9%Fq
/** lxZXz JkqZ
* 获得总页数 dIm m},
*/ #7{a~-S
publicint getPageNum(){ w]_a0{Uh
return(count - 1) / num + 1; *RPI$0
} zw?6E8$h
C$8=HM3
/** Sc&_6}K
* 获得本页的开始编号,为 (p-1)*num+1 S:gP\Atf>
*/ # V+e
publicint getStart(){ * 7CI q
return(p - 1) * num + 1; _),@^^&x
} \;}dSSB1
"T PMSx&Ei
/** o%:eYl
* @return Returns the results. g:HIiGN0Ic
*/ 2sngi@\
publicList<E> getResults(){ P+[R 0QS
return results; 8MIHp[vm%
} Ne%X:h
T~la,>p|}
public void setResults(List<E> results){ c}A^0,"z>
this.results = results; AOpfByw
} fOfp.`n
FwyPmtBj
public String toString(){ ]l`DR4
=
StringBuilder buff = new StringBuilder 2bqwnRT}
VrpYBU
(); {PZe!EQ
buff.append("{"); 3iB8QO;pp
buff.append("count:").append(count); Nbr{)h
buff.append(",p:").append(p); `g7'
)MSy
buff.append(",nump:").append(num); q07>FW R
buff.append(",results:").append ;RXv%ML
]Sh&8 #
(results); ][3 "xP
buff.append("}"); ctf'/IZ5
return buff.toString(); -
0zo>[c/p
} $/Mk.(3'P
~34$D],D
} QeGU]WU{
1z)+P1nH]
6(.&y;