Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 IbC8DDTD
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 65 P*Gu?
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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 Epl\(
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 {\SJr:
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分页支持类: L/YEW7M
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java代码: rryC^Vma
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package com.javaeye.common.util; z-J?x-<
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import java.util.List; 37F&s
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publicclass PaginationSupport { wWaJ%z>3y
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publicfinalstaticint PAGESIZE = 30; o>#ue<Bc6
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privateint pageSize = PAGESIZE; =vpXYj
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privateList items; wa)E.(x
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privateint totalCount; +s`HTf
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privateint[] indexes = newint[0]; +(pFU\&U3H
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privateint startIndex = 0; gf&\)"
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public PaginationSupport(List items, int , sOdc!![
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totalCount){ vg.K-"yQW
setPageSize(PAGESIZE); |e]2 >NjQa
setTotalCount(totalCount); #77p>zhY
setItems(items); :Sd"~\N+
setStartIndex(0); (FY<%.Pa
} R9!GDKts%
; xz}]@]Ar
public PaginationSupport(List items, int O1
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totalCount, int startIndex){ I?z*.yA*
setPageSize(PAGESIZE); GY3g`M
setTotalCount(totalCount); ZQVr]/W^r
setItems(items); o)M=; !
setStartIndex(startIndex); /`2t$71)
} g.V{CJ*V
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public PaginationSupport(List items, int .*x |TPv{
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totalCount, int pageSize, int startIndex){ B=R9K3f
setPageSize(pageSize); 0wA?.~ L
setTotalCount(totalCount); l_1y#B-k5
setItems(items); ]E:P-xTwaI
setStartIndex(startIndex); ;;Y>7Kn!u
} 5LF#w_x
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publicList getItems(){ 0C,2gcq
return items; M?nYplC
} ,~TV/l<
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publicvoid setItems(List items){ c:@lR/oe"
this.items = items; 8etNS~^
} !e0OGf
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publicint getPageSize(){ 9[9
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return pageSize; MIn6p
} aOOkC&%
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publicvoid setPageSize(int pageSize){ d*===~
this.pageSize = pageSize; ?S~@Ea8/M
} "L)=Y7Dx
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publicint getTotalCount(){ ]6*+i $
return totalCount; }23#z
} -!s?d5k")
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publicvoid setTotalCount(int totalCount){ 4b}94e@(N
if(totalCount > 0){ S*D Bzl
this.totalCount = totalCount; $.g)%#h:
int count = totalCount / +Y9n@`
#6'+e35^ 8
pageSize; ;"1
if(totalCount % pageSize > 0) br[n5
count++; ~t,-y*=
indexes = newint[count]; g3h:oQCS
for(int i = 0; i < count; i++){ IuW5LS
indexes = pageSize * s7(I
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i; Li{R?Osx
} EXz{Pqz
}else{ "+BNas^rF
this.totalCount = 0; _]/&NSk
} M6MtE_E
} f:K3 P[|
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publicint[] getIndexes(){ aP}%&{iC*
return indexes; h{BO\^6x
} _ITA $#
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publicvoid setIndexes(int[] indexes){ mKh<M)Bz
this.indexes = indexes; F VVpyB|
} LL}b]B[
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publicint getStartIndex(){ {-'S#04
return startIndex; 4pw:O^v
} Rc.8j,]
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publicvoid setStartIndex(int startIndex){ Q|1X|_hs
if(totalCount <= 0) E{#Y=
this.startIndex = 0; J nzI-
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elseif(startIndex >= totalCount) bpv?$j-j
this.startIndex = indexes $(PWN6{\r^
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[indexes.length - 1]; OpT0V]k^"9
elseif(startIndex < 0) XY*KWO
this.startIndex = 0; V!3.MQM
else{ =#Qm D=
this.startIndex = indexes a#NP69
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[startIndex / pageSize]; ud@7%%
} OQC.p,SO
} &qP@WFl
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publicint getNextIndex(){ {W5D)
int nextIndex = getStartIndex() + l*0`{R
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pageSize; j1hx{P'
if(nextIndex >= totalCount) CNRiK;nQ
return getStartIndex(); [ ]LiL;A&
else "p[FFg
return nextIndex; 320g!r
} ?->&)oAh
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publicint getPreviousIndex(){ pSml+A:
int previousIndex = getStartIndex() - ap%
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pageSize; } F; Nh7?
if(previousIndex < 0) ~H+W[r}
return0; S}T*g UO
else OlJkyL8|
return previousIndex; zV<vwIUrr
} Dqu][~oQ
C $r]]MSj
} Om/mpU/U
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抽象业务类 ^9zFAY.|
java代码: z/IZ ;K_e
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/** V(LE4P1
* Created on 2005-7-12 /cN. -lEo%
*/ (XDK&]U
package com.javaeye.common.business; IxxA8[^V
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import java.io.Serializable; {q}#
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import java.util.List; ji(Y?vhQt
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import org.hibernate.Criteria; oB8x_0#n
import org.hibernate.HibernateException; V,W":&!x
import org.hibernate.Session; \a|bx4M
import org.hibernate.criterion.DetachedCriteria; sJHN4
import org.hibernate.criterion.Projections; U $ bLt
import J% t[{
YhzDi>hob
org.springframework.orm.hibernate3.HibernateCallback; 1D pRm(
import M\f1]L|8d
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org.springframework.orm.hibernate3.support.HibernateDaoS vMQvq9T}
> 10pk
upport; .vbUv3NI
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import com.javaeye.common.util.PaginationSupport; 51\N+
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public abstract class AbstractManager extends ;Npv 2yAab
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HibernateDaoSupport { :<}.3 Q?&
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privateboolean cacheQueries = false; WRWcB
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privateString queryCacheRegion; NSPa3NE
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publicvoid setCacheQueries(boolean hR] AUH
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cacheQueries){ -5Km9X8
this.cacheQueries = cacheQueries; hjgxCSp
} \40d?N#D
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publicvoid setQueryCacheRegion(String 6}RRrYL7I
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queryCacheRegion){ pNHO;N[&
this.queryCacheRegion = >^ E
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queryCacheRegion; njk1x
} y.LJ5K$&a
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publicvoid save(finalObject entity){ ;8G( l
getHibernateTemplate().save(entity); LD~s@}yH>
} --~m{qmy
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publicvoid persist(finalObject entity){ 0F\e*{gc
getHibernateTemplate().save(entity); @"`{gdB$
} 2`o}neF{
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publicvoid update(finalObject entity){ 0V:DeX$bZ
getHibernateTemplate().update(entity); RRNoX}
} `y26OYo
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publicvoid delete(finalObject entity){ as{^~8B
getHibernateTemplate().delete(entity); ||lI_B
} .o2]ndT/J
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publicObject load(finalClass entity, 8"#Ix1#
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finalSerializable id){ sp0j2<$a
return getHibernateTemplate().load CFW\
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(entity, id); w
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} +!I7(gL
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publicObject get(finalClass entity, $=c79Al(
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finalSerializable id){ b,U3b})(
return getHibernateTemplate().get M=n_;3,o
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(entity, id); @[qGoai
} C^hHt,&
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publicList findAll(finalClass entity){ ',MiD=_
return getHibernateTemplate().find("from l#FW#`f
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" + entity.getName()); 7H-,:8
} q>~\w1%}a\
}@*Me+
publicList findByNamedQuery(finalString GnE%C2L-
R?Dbv'lp>
namedQuery){ ~ E)[!y
return getHibernateTemplate K8`M~P.
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().findByNamedQuery(namedQuery); cm8-L[>E
} 7-oH >OF^
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publicList findByNamedQuery(finalString query, 5dVSir
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finalObject parameter){ 1`tE Hu.
return getHibernateTemplate LvJ')HG
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().findByNamedQuery(query, parameter); 'JBf*p".
} FTy`#*7Ul
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publicList findByNamedQuery(finalString query, +$#YW5wy
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finalObject[] parameters){ 1@nGD<,.
return getHibernateTemplate %`%xD>![
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().findByNamedQuery(query, parameters); kF9T 9
} ,KlTitJl\+
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publicList find(finalString query){ yJaQcGxE"
return getHibernateTemplate().find wl{Fx+<^3
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(query); ];waK2'2
} .(Gq9m[~8H
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publicList find(finalString query, finalObject IED7v
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parameter){ rSIb1zJ
return getHibernateTemplate().find 8@)/a
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(query, parameter); ,`/J1(\nd
} O[3AI^2
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public PaginationSupport findPageByCriteria `x"0
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(final DetachedCriteria detachedCriteria){ J}7iXTh
return findPageByCriteria \o^M ,yI
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Gd)@PWK
} BJ3st
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public PaginationSupport findPageByCriteria D?rQQxb
#&G^%1!
(final DetachedCriteria detachedCriteria, finalint IKM=Q.
7j
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startIndex){ =:U63
return findPageByCriteria jg?B][
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(detachedCriteria, PaginationSupport.PAGESIZE, W"fdK_F\
)-824?Nl:
startIndex); W:uIG-y~
} v7O&9a;
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public PaginationSupport findPageByCriteria ZpPm>|w
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, _9E7;ew
finalint startIndex){ ;m}lmq,
return(PaginationSupport) da3]#%i0
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getHibernateTemplate().execute(new HibernateCallback(){ _pQ9q&i4
publicObject doInHibernate guv)[:cd;
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(Session session)throws HibernateException { g2 uc+p
Criteria criteria = wobTT1!|
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detachedCriteria.getExecutableCriteria(session); &yzC\XdA
int totalCount = 3ug{1M3
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((Integer) criteria.setProjection(Projections.rowCount U]dz_%CRP
*5 FSq
()).uniqueResult()).intValue(); j_SRCm~:
criteria.setProjection 'DlY8rEGP
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(null); .eW}@1+[;
List items = in -/
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criteria.setFirstResult(startIndex).setMaxResults \1f$]oS
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(pageSize).list(); 3A]Y=gfa
PaginationSupport ps = zT0rvz1),M
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new PaginationSupport(items, totalCount, pageSize, l%lkDh!$"
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startIndex); Z~$=V:EA?
return ps; $k*E^~qT
} {Q^P<
}, true); -G]\"ZGi
} 2t\a/QE)E
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public List findAllByCriteria(final ?stx3sZ
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DetachedCriteria detachedCriteria){ x;lIw)Ti
return(List) getHibernateTemplate (L8H.|.
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().execute(new HibernateCallback(){ ]q7\
publicObject doInHibernate +60zJ4
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(Session session)throws HibernateException { _Qs)~
Criteria criteria = Lie\3W
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detachedCriteria.getExecutableCriteria(session); cnC&=6=a<
return criteria.list(); iN5~@8jAzz
} eI8^T?
}, true); H:4r6-{
} 4VSIE"8e
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public int getCountByCriteria(final 6T&6N0y+9
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DetachedCriteria detachedCriteria){ &G5+bUF,
Integer count = (Integer) X !NH?0)
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getHibernateTemplate().execute(new HibernateCallback(){ "m0>u,HmI
publicObject doInHibernate ;o_4)+}
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(Session session)throws HibernateException { gCz^JM
Criteria criteria = ~HI|t2C
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detachedCriteria.getExecutableCriteria(session); IfeG"ua|
return V'
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criteria.setProjection(Projections.rowCount / _-?NZ
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()).uniqueResult(); 2sjV*\Udf
} 'y}l9alF
}, true); V/$qD
return count.intValue(); Fl]$ql
} B4pheKZ2
} M' "S:
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用户在web层构造查询条件detachedCriteria,和可选的 ;S"^O
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 i|*(vH&D.
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PaginationSupport的实例ps。 ?lnX."eAdB
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ps.getItems()得到已分页好的结果集 M['8zN
ps.getIndexes()得到分页索引的数组 ~ULuX"n
ps.getTotalCount()得到总结果数 K;,n?Q w
ps.getStartIndex()当前分页索引 BOrfKtG\
ps.getNextIndex()下一页索引 HtgVD~[]
ps.getPreviousIndex()上一页索引 he8y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 \kF}E3~+#
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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 i{I'+%~R
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一下代码重构了。 /~{8/u3
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我把原本我的做法也提供出来供大家讨论吧: CtTG`)"|
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首先,为了实现分页查询,我封装了一个Page类: Yn+/yz5k_
java代码: AmM^&
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/*Created on 2005-4-14*/ y)t< r
package org.flyware.util.page; Q%o ]&Hdn
+M$2:[xRT
/** QKL5!
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* @author Joa Wy.2*+5FX0
* _&FcHwRy
*/ Qf6]qJa|
publicclass Page { Xt(w+
KV k
36;$
/** imply if the page has previous page */ oL1m<cQo9
privateboolean hasPrePage; y&-wb'==p
AFGWlC#`
/** imply if the page has next page */ *>n<7T0
privateboolean hasNextPage; %a&Yt
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/** the number of every page */ - U!:.
privateint everyPage; TFb9gOTJ
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/** the total page number */ M&Sjo' ( .
privateint totalPage; ..UmbJJ.u
#WwQ^6ESc
/** the number of current page */ GM%%7 ^uE
privateint currentPage; "1$OPt5
P6&@fwJ<
/** the begin index of the records by the current j!B+Q
/B.\ 6
query */ ><}FyK4C
privateint beginIndex;
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/** The default constructor */ ~J^Gzl
public Page(){ I7ZY9W(S
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} vz#VW
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/** construct the page by everyPage ;XNe:g.CR
* @param everyPage 9G_bM(q'^2
* */ Ch%W
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public Page(int everyPage){ 0+jR,5|
this.everyPage = everyPage; 7(rNJPrU~=
} }J73{
3 GmU$w
/** The whole constructor */ #|k;nFJ
public Page(boolean hasPrePage, boolean hasNextPage, }u:@:}8K
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int everyPage, int totalPage, ;wwhW|A
int currentPage, int beginIndex){ U\a.'K50F
this.hasPrePage = hasPrePage; };6[Byf
this.hasNextPage = hasNextPage; vh 5`R/<3
this.everyPage = everyPage; uCO-f<b
this.totalPage = totalPage; u>o<ua
p
this.currentPage = currentPage; 0$NcxbM
this.beginIndex = beginIndex; OFJ49X
} GEj/Z};;[b
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/** JJ`RF
* @return KI)jP((
* Returns the beginIndex. 7s@%LS
*/ C"}CD{<H]M
publicint getBeginIndex(){ $*w]]b$Dn
return beginIndex; ,<R/jHZP9
} tkX7yg>`
p vone,y2
/** {:BAh5e|
* @param beginIndex y|X</3w
* The beginIndex to set. C^9G \s'
*/ *`$Y!uzG:\
publicvoid setBeginIndex(int beginIndex){ GcN[bH(@
this.beginIndex = beginIndex; ZGO%lkZ.
} x}v]JEIf[Q
~2u~}v5m7
/** 8CCd6)cG
* @return C".nB12
* Returns the currentPage. Xi"+{6
*/ %+Hhe]J ld
publicint getCurrentPage(){ !SRElb A;i
return currentPage; 6[ }~m\cY
} WqQAt{W/<
^ [FK<9
/** 1./uJB/
* @param currentPage ffyDi 1Q
* The currentPage to set. 3ht>eaHi
*/ Y' K+O
publicvoid setCurrentPage(int currentPage){ JxI\ss?O
this.currentPage = currentPage; {l/j?1Dxq
} 7|$cM7_r
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/** '"u>;Bq
* @return 3"v
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* Returns the everyPage. EJC{!06L'/
*/ 0zJT_H+
publicint getEveryPage(){ st~
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return everyPage; <zd_-Ysn
} $ZnLY uGb
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/** J-iFAKN
* @param everyPage R`M>w MLH
* The everyPage to set. aqL#g18
*/ 4)- ?1?)
publicvoid setEveryPage(int everyPage){ iYbp^iVg
this.everyPage = everyPage; IQz"FH?
} War<a#0
ZiR },F/
/** ] oOSL=~c
* @return R#"LP7\
* Returns the hasNextPage. d yH<D5
*/ 9)c{L<o}T
publicboolean getHasNextPage(){ WY>r9+A?W
return hasNextPage; ^a>3U l{
} WG~|sLg
MTnW5W-r9
/** L@mNfLK
* @param hasNextPage 'YQVf]4P
* The hasNextPage to set. 6_UCRo5h%
*/ ]o!rK<
publicvoid setHasNextPage(boolean hasNextPage){ j 3/ I=
this.hasNextPage = hasNextPage; " a&|{bv
} 5Z8Zb.
X667*L^
/** t(~V:+W 9
* @return $ ,:3I*}be
* Returns the hasPrePage. 2OA0rH"v
*/ ?"hrCEHV{9
publicboolean getHasPrePage(){ egXHp<bqw
return hasPrePage; g?7I7W~?`
} T<o^f
n,H
, 0hk)Vvr3
/** yr;~M{{4
* @param hasPrePage %yyvB5Y^
* The hasPrePage to set. ul@swp
*/ ?&gqGU}
publicvoid setHasPrePage(boolean hasPrePage){ 54lU~ "
this.hasPrePage = hasPrePage; kA .U2
} L'Yg$9 Vz
g)3HVAT
/** 2uCw[iZM
* @return Returns the totalPage. #oYPe:8|m
* Mzg zOM
*/ *dAQ{E(rO
publicint getTotalPage(){ B0M(&)!%
return totalPage; =~D QX\
} yjF;%A/0
gTM*td(~^
/** _\2Ae\&c
* @param totalPage 74w Df
* The totalPage to set. mi';96
*/ !=3Ce3-
publicvoid setTotalPage(int totalPage){ a 23XrX
this.totalPage = totalPage; 4\_~B{kzZ
} & FpoMW
XsEotW
} i^SPNs=
s+-V^{Ht
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/ucS*m:<x
Pf:;iXH?
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 Ql1J?9W
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个PageUtil,负责对Page对象进行构造: {y%|Io`P
java代码: <r1/& RW,
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/*Created on 2005-4-14*/ QPyHos`
package org.flyware.util.page; =T- jG_.H
AX] cM)w
import org.apache.commons.logging.Log; lD#S:HX
import org.apache.commons.logging.LogFactory; 96d&vm~m1
so>jz@!EE
/** RxA:>yOPn
* @author Joa zN&m-nrw
* "!9FJ Y
*/ ;U&~tpd
publicclass PageUtil { >H,5MM!
~='}(Fg:
privatestaticfinal Log logger = LogFactory.getLog W) ?s''WE;
m2\[L/W]
(PageUtil.class); %w;wQ_
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/** 9yK\<6}}QH
* Use the origin page to create a new page ~[Z(6yX
* @param page 4jw q$G
* @param totalRecords ;--p/h*.
* @return cz1 m05E
*/ "9#hk3*GqX
publicstatic Page createPage(Page page, int e8 c.&j3m
wWVB'MRXB,
totalRecords){ %x8vvcO^t
return createPage(page.getEveryPage(), pN{XGkX.
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page.getCurrentPage(), totalRecords); ]zz%gZz
} #G\Ae:O
Gce[RB:
/** D^S"6v"z
* the basic page utils not including exception MM*9Q`cB
(_R!:H(]m
handler +bk+0k9k5
* @param everyPage H<"EE15
* @param currentPage ~m4LL[
* @param totalRecords }O\g<ke:u
* @return page 8:U0M'}u>
*/ nK`H;k
publicstatic Page createPage(int everyPage, int g,B@*2Uj
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currentPage, int totalRecords){ mr,GHx
everyPage = getEveryPage(everyPage); 8l<~zIoO
currentPage = getCurrentPage(currentPage); tm.&k6%
int beginIndex = getBeginIndex(everyPage, wj8\eK)]L
G+tzp&G@
currentPage); ]YY4{E(9d
int totalPage = getTotalPage(everyPage, On}b|ev
dKmPKeJM
totalRecords); }tJMnq/m($
boolean hasNextPage = hasNextPage(currentPage, Q6n8 ,2*
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totalPage); F.D6O[pZ
boolean hasPrePage = hasPrePage(currentPage); a
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D>kkA|>
returnnew Page(hasPrePage, hasNextPage, g`,(O
everyPage, totalPage, o3`0x9{
currentPage, m|[cEZxHB
I]B9+Z?xo
beginIndex); +B7UGI
} .:/X~{
UJ`%uLR~
privatestaticint getEveryPage(int everyPage){ :(I=z6
return everyPage == 0 ? 10 : everyPage; xzRC %
} ,88%eX|
Si|8xq$E;
privatestaticint getCurrentPage(int currentPage){ SNV;s,
return currentPage == 0 ? 1 : currentPage; XV!UeBq
} Ds\f?\Em
Lya?b
privatestaticint getBeginIndex(int everyPage, int "?YpF2pD
5hB2:$C
currentPage){ }J=z O8OL
return(currentPage - 1) * everyPage; l> >BeZ
} *gI9CVfQl
-Q!?=JNtQ
privatestaticint getTotalPage(int everyPage, int )
|hHbD^V
t;[Q&Jl
totalRecords){ ;~s@_}&
int totalPage = 0; U7G|4(
6.4,Qae9E
if(totalRecords % everyPage == 0) s_,&"->
totalPage = totalRecords / everyPage; NO#^_N`#\
else a[gN+DX%L
totalPage = totalRecords / everyPage + 1 ; <7X+-%yb;
%;G!gJeE
return totalPage; 3lNw*M|")
} i4
tW8Il
m$$98N
privatestaticboolean hasPrePage(int currentPage){ \y/+H
return currentPage == 1 ? false : true; UmQ'=@^kR
} +'I8COoiv%
o6
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privatestaticboolean hasNextPage(int currentPage, PiIILX{DuH
Xgm9>/y
int totalPage){ k?=V?JWY
return currentPage == totalPage || totalPage == ?Qs>L~
8%9OB5?F6
0 ? false : true; FdJC@Y-#uA
} ~LzTqMHM
cl-i6[F
wwmODw<tT
} ]H<C Rw
x]U (EX`t$
}c,}+{q
dUJNr_
IN]bAd8"
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。 }fs;yPl,
u]cnbm
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 JGD{cr[S
efP2 C\
做法如下: 7+u%]D!
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 5cQBqH]
_>:g&pS/
的信息,和一个结果集List: Xc5[d`]
java代码: Q<``}:y|>
@kwD$%*0
)Bk?"q
/*Created on 2005-6-13*/ z_l3=7R
package com.adt.bo; L ou4M
y$V{yh[:
import java.util.List; r5iO%JFg
Pjb9FCA'
import org.flyware.util.page.Page; |_2ANWHz
Da-(D<[0
/** p r0V) C6
* @author Joa ,n!xzoX_
*/ '\*Rw]bR|
publicclass Result { = xX^
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private Page page; sqZHk+<%
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private List content; MthThsr7
=OZ_\vO
/** NxX1_d
* The default constructor Gj_b GqF8}
*/ ia_8$>xW+
public Result(){ };!c]/,
super();
B-gr2-
} }\*Sf[EMD
E0DEFB
/** eXaDx%mM
* The constructor using fields Rt:PW}rFf
* L2h+[f
* @param page 99:L#0!.W
* @param content }b^lg&$(
*/ 5~"=Fm<uD
public Result(Page page, List content){ zm .2L
this.page = page; 86I*
this.content = content; 3 z#;0n}
} u ?Xku8 1l
zn~m;0Xi
/** v1lj /A
* @return Returns the content. P%lLKSA
*/ T?ZMmUE
publicList getContent(){ 6e*b;{d
return content; N_DgnZ7*
} |5/[0V-vy
:gVjBF2
/** 09?<K)_G
* @return Returns the page. '~cEdGD9H
*/ 7@"X~C
public Page getPage(){ 7A|jnm
return page; *j*
WE\
} Mww]l[1'EL
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/** u~kwNN9t3
* @param content "%]dC{
* The content to set. wg1pt1 `
*/ HlSuhbi'@
public void setContent(List content){ wm8x1+P
this.content = content; :jX~]1hpmA
} >g2B5KY
>8tuLd*T
/** yi?&^nX@9,
* @param page 7a<qP=J
* The page to set. dW`D?$(@,
*/ \}=b/FL=U
publicvoid setPage(Page page){ |<*(`\'w
this.page = page; !%X`c94
} Mt Z(\&~
} QBy*y $
D=>^m=?0
Em;b,x*U
]`XuE-Uh
4Dia#1$:J
2. 编写业务逻辑接口,并实现它(UserManager, }BrE|'.j'
gNd
J=r4
UserManagerImpl) QA(,K}z~^S
java代码: ^IpiNY/%Q
1#<E]<='t
}(K6 YL
/*Created on 2005-7-15*/ hI8C XG
package com.adt.service; 2~DPq p[
#U}U>4'
import net.sf.hibernate.HibernateException; FudD
GvOAs-$
import org.flyware.util.page.Page; ks;w c"k"
5uer
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import com.adt.bo.Result; }A7qIys$4
/8>/"Z2S
/** ^gyp-
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* @author Joa m4wTg
8LJ
*/ ["<(\v9P)
publicinterface UserManager { jTr4A-"
([-=NT}Aq
public Result listUser(Page page)throws o
z{j2%
syf"{bBe
HibernateException; 61/zrMPn
8!GLw-kb
} QP%Fz#u`
ek)(pJ(+#
ef;L|b%pp
N{t:%[
i_Z5SMZ
java代码: t`,IW{
ZD%_PgiT
YnWl'{[ C
/*Created on 2005-7-15*/ <WJ0St
package com.adt.service.impl; NCFV
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import java.util.List; Td1ba ^J
*v ^"4
import net.sf.hibernate.HibernateException; Sp,Q,Q4
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import org.flyware.util.page.Page; |S:!+[
import org.flyware.util.page.PageUtil; xPup?oP >
!<zzP LC
import com.adt.bo.Result; FraW6T}_
import com.adt.dao.UserDAO; d$rUxqB.
import com.adt.exception.ObjectNotFoundException; o}+Uy
import com.adt.service.UserManager; 78CJ
|u r~s$8y-
/** X,+}syK
* @author Joa =awO63j>
*/ m8j-lNu
publicclass UserManagerImpl implements UserManager { cC^C7AAq^
8]":[s6x
private UserDAO userDAO; -5v.1y=!L
|cGeL[
/** 7E3SvC|M
* @param userDAO The userDAO to set. +`zi>=
*/ :n9xH
publicvoid setUserDAO(UserDAO userDAO){ p_qm}zp
this.userDAO = userDAO; 5f'g3'
} C<t'f(4s`u
V9j1j}
r
/* (non-Javadoc) } .3]
* @see com.adt.service.UserManager#listUser QrckTO
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(org.flyware.util.page.Page) Lp`<L -s
*/ L\m !8o4
public Result listUser(Page page)throws <cv2-?L{
'gZbNg=&[
HibernateException, ObjectNotFoundException { H<Kkj
int totalRecords = userDAO.getUserCount(); #} ~p^ 0
if(totalRecords == 0) ).}k6v[4)
throw new ObjectNotFoundException :{b6M/
+'['HQ)
("userNotExist"); {jM<t
page = PageUtil.createPage(page, totalRecords); xR|eye R
List users = userDAO.getUserByPage(page); D<bU~Gd,P
returnnew Result(page, users); vDW&pF_eI>
} 4l
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HKiVEg
} H*{k4
r=DHt&x=
`e?;vA&
G?1x+H;o5
S -6"f/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ";_K x={
PG6L]o^
询,接下来编写UserDAO的代码: J7ktfyQ0W
3. UserDAO 和 UserDAOImpl: `xX4!^0Hm
java代码: ;Lsjh#
x'2 ,sE
"VDk1YX_&l
/*Created on 2005-7-15*/ umm \r&]A
package com.adt.dao; Wg`+u
3|~(?4aE
import java.util.List; ]^; b
Kunle~Ro
import org.flyware.util.page.Page; 3V/_I<y
]HyHz9QkL
import net.sf.hibernate.HibernateException; i $[,-4v
a:yB%:2
/** XhE$&Ff
* @author Joa abICoP1zQ
*/ ,Um 5S6 Z
publicinterface UserDAO extends BaseDAO { TZh\#dp4l
6;
5)/ q
publicList getUserByName(String name)throws n9kd2[s|
&@4.;u
HibernateException; NWJcFj_
Z[#I"-Q~:
publicint getUserCount()throws HibernateException; 'f-
N
b3I%r
publicList getUserByPage(Page page)throws ~>#LOT `
Ql~#((K
HibernateException; _\,rX\
^91sl5c8yD
} J4gI=@e
?eL='>Ne
9 m\)\/V
=$b-xsmeG
{A]k%74-a
java代码: uX[O,l^}
-l-AToO4
<Gr9^C
/*Created on 2005-7-15*/ 8?e
package com.adt.dao.impl; ljup#:n
7<EJo$-j
import java.util.List; M MAAHo
?_VRfeztw
import org.flyware.util.page.Page; *he7BUO
e>
ar
import net.sf.hibernate.HibernateException; <TI3@9\qXE
import net.sf.hibernate.Query; f\h%; X
,dHP`j ?
import com.adt.dao.UserDAO; [#7y[<.P
lir&e
9I+
/** D3%l4.h
* @author Joa T@(6hEmP,
*/ `]K,'i{R
public class UserDAOImpl extends BaseDAOHibernateImpl QjQ4Z'.r >
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implements UserDAO { u=vh
Z%A]
qPsyqn?Y|
/* (non-Javadoc) ]dd[WHA
* @see com.adt.dao.UserDAO#getUserByName w`M]0'zls
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(java.lang.String) C0zrXhY_v
*/ @(i*-u3Tq
publicList getUserByName(String name)throws jZrY=f
]|,vCKju
HibernateException { iH[E=
6*
String querySentence = "FROM user in class +yth_9
De;, =BSp
com.adt.po.User WHERE user.name=:name"; (tJ91SBl
Query query = getSession().createQuery Qn*6D
G-2EQ.
(querySentence); /ca(a\@R
query.setParameter("name", name); ?Rlgv5P!
return query.list(); r k@UsHy
} !loO%3_)
-dg} BM
/* (non-Javadoc) .SG0}8gW
* @see com.adt.dao.UserDAO#getUserCount() GL/ KB
*/ GXO4x|08F
publicint getUserCount()throws HibernateException { *0O<bm
int count = 0; >5c]aNcv
String querySentence = "SELECT count(*) FROM #De(*&y2
;JYoW{2
user in class com.adt.po.User"; <R>Q4&we(
Query query = getSession().createQuery ]+AAT=B<!
Y]~IY?I
(querySentence); Bk+{}
count = ((Integer)query.iterate().next P2>:p%Z
_~PO
()).intValue(); ,`<]>;s
return count; )+?HI^-[S
} fc3 Fi'^
Cgo9rC~]
/* (non-Javadoc) 02,W~+d1
* @see com.adt.dao.UserDAO#getUserByPage 'X54dXS?l
t7&Dwmck9
(org.flyware.util.page.Page) HQl~Dh0DJ
*/ cu<y8
:U<
publicList getUserByPage(Page page)throws E&'#=K[
1ADv?+j)A/
HibernateException { V+46R
]
String querySentence = "FROM user in class u-kZW1wrQ
xLZ bU4
com.adt.po.User"; yu=piP
Query query = getSession().createQuery ( :iPm<
9T$u+GX'
(querySentence); E.9^&E}PG
query.setFirstResult(page.getBeginIndex()) S4)A6z$
.setMaxResults(page.getEveryPage()); B_cgWJ*4
return query.list(); @O'I)(To
} g#}tm<
};^}2Xo+
}
A0OB$OK
%uua_)
bfhz?,b
{a.
<`
T~h.=5
至此,一个完整的分页程序完成。前台的只需要调用 $D}"k!H
FJ}gUs{m
userManager.listUser(page)即可得到一个Page对象和结果集对象 /eb-'m
@C=m?7O98
的综合体,而传入的参数page对象则可以由前台传入,如果用 fQO
""qh
ZL,6_L/
webwork,甚至可以直接在配置文件中指定。 L/%Y#
}Bi@?Sb
下面给出一个webwork调用示例: W/=7jM
java代码: %W&1`^Jl
6m@0;Ht
~XKZXGw
/*Created on 2005-6-17*/ SwX@I6huM
package com.adt.action.user; oBC]UL;8xJ
bM ^7g
import java.util.List; 9>;} /*:H
UhdqY]
import org.apache.commons.logging.Log; _Z$?^gn
import org.apache.commons.logging.LogFactory; bJPJ.+G7
import org.flyware.util.page.Page; o[oqPN3$Y
}2=hd. .
import com.adt.bo.Result; E>"8/
import com.adt.service.UserService; ;Gh>44UM[
import com.opensymphony.xwork.Action; XfDX:b1p
7gr^z)${J
/** W"t"X ~T3
* @author Joa ]VDn'@uM
*/ Bq;1^gtpe
publicclass ListUser implementsAction{ +KP_yUq[
7f*
RM
privatestaticfinal Log logger = LogFactory.getLog j_V/GnEQ
]=Pu\eE
(ListUser.class); x 'mF&^
7f
r>ZY^
private UserService userService; 0MrN:M2B
^vM_kArA
private Page page; +99Bi2H}o
QtlT&|$
privateList users; \XDmK
[8z&-'J=
/* cJ/4Gl
* (non-Javadoc) Yt*vqm[WV
* 4DM*^=9E
* @see com.opensymphony.xwork.Action#execute() d- kZt@DL=
*/ OpUA{P
publicString execute()throwsException{ lQ$+JX;n(y
Result result = userService.listUser(page); 1$(
page = result.getPage(); $+jy/:]D
users = result.getContent(); g}Mi9Kp
return SUCCESS; !5~k:1=
} }*Zo6{B-
- wWRm
/** ~bGC/I;W>
* @return Returns the page. %6HX*_Mr&
*/ ?;RD u[eD
public Page getPage(){ ^RDU
p5,T
return page; _D
JCsK|
} zR/IqW.`9
Bq{]Eh0%
/** }^9paU
* @return Returns the users. 6klD22b2$
*/ HzEGq,.
publicList getUsers(){ ^/<|f,2
return users; )#PtV~64
} =y<0UU
Gnv!]c&S>l
/** {$|/|*
* @param page I=5dYq4 l
* The page to set. O4!9{
*/ xEC2@J
publicvoid setPage(Page page){ $P;UoqG<&
this.page = page; Man^<T%F
} Xb0!( (A
8t=3
/** BUDGyl/=
* @param users X|Dpt2A=
* The users to set. 0e\y~#-
*/ j/'
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publicvoid setUsers(List users){ s>r ^r%uK
this.users = users; QoWR@u6a
} Y$+QNi
lvPpCAXY
/** wE4;Rk1
* @param userService vcM~i^24)
* The userService to set. %l;*I?0H
*/ 8,y{q9O
publicvoid setUserService(UserService userService){ m_$JWv\|\
this.userService = userService; K( z[}
} MHFaSl
} 3sb 5E]P
vzcz<i )
ydup)[n
{lMqcK
yf?W^{^|
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, ^}hZ'<PK
U3+A MVnB
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 Bz:&f46{
%",ULtZ+
么只需要: }7Jp :. qk
java代码: 5;(0 $4I
W} Zb~[,
gwJ}]Tf
<?xml version="1.0"?> d EIa=e|
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork K-6p'|
+dM.-wW
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 71*>L}H
PF67z]<o
1.0.dtd"> v4C3uNW
ee^4KKsh\
<xwork> jr:drzr{I
|eF.ZC)QWh
<package name="user" extends="webwork- ,H@TYw
b*`fLrqV.
interceptors"> CC>($k"
NZfd_? 3
<!-- The default interceptor stack name $ hoYkA
j3LNnZY
--> 0R*}QXph
<default-interceptor-ref NN11}E6
:v#8O~
name="myDefaultWebStack"/> ey*,StT5a
77tZp @>hn
<action name="listUser" ]` K[W &
j
C9<hLt
class="com.adt.action.user.ListUser"> %]!?{U\*k
<param ExQ--!AC=
w~]}acP
name="page.everyPage">10</param> F=:c5z
<result $82zy q
>j-
b5g"g
name="success">/user/user_list.jsp</result> RW)k_#%=
</action> &*jixqzvn
HwM/}-t
</package> leR"j
418gcg6)
</xwork> PB@-U.Z
$6Z[|9W^A
ah>Dqb*
9T/<x-FD
sZT VM9<)
il7!}
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 %![4d;Z%x
@YsL*zw
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 4 #G3ew
[XxA.S)x3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 *50ZinfoG
9a-]T=5Ee
S`4e@Z$
IN>TsTo
N]*!8
我写的一个用于分页的类,用了泛型了,hoho
Re{ej
^,>}%1\
java代码: (KZUvsS k
+Z]y #=
Y[T J;O!R
package com.intokr.util; 95VqaR,
r^e-.,+
import java.util.List; D8W(CE^}
pc^E'h:
/** u"eZa!#
* 用于分页的类<br> $*g{[&L|6
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ^g\h]RD}
* %N!h38N2
* @version 0.01 JW2W>6Dgv[
* @author cheng .ZM]%[4
*/ U24V55ZnI
public class Paginator<E> { f7K8m|
privateint count = 0; // 总记录数 omr:C8T>
privateint p = 1; // 页编号 -B",&yTV
privateint num = 20; // 每页的记录数 XPrY`,kN
privateList<E> results = null; // 结果 Fv<]mu
Gl=@>Dc%
/** H#_}^cGPR=
* 结果总数 G6f%/m`
*/ j^:b-:F
publicint getCount(){ A-}PpH~.Z
return count; +ESX.Vel
} CRP7U
[@jp9D
H
publicvoid setCount(int count){ aIY$5^x
this.count = count; J*/$ywI
} ;9 lqSv/6
&0?DL
/** H;4oZ[g
* 本结果所在的页码,从1开始 uV/)Gb*j
* }6F_2S3c
* @return Returns the pageNo. \t[
hg
*/ ^a: Saq-}
publicint getP(){ jp"XS
return p; X+fuhcn
} K%o6hBlk_
T
"ZQPLg
/** @DRfNJ}
* if(p<=0) p=1 \3,$YlG
* % jYQ
* @param p 8.6no
*/ 9N`+ O
publicvoid setP(int p){ yN%3w0v
if(p <= 0) }mkA Hmu4
p = 1; q=(M!9cE
this.p = p; t"jIfU>'a/
} g9RzzE!
,K"r:)\
/** =P@M&Yy'
* 每页记录数量 ";%e~
=
*/ eG a#$x?.
publicint getNum(){ hlYS=cgY=
return num; Ih9O Rp7
} rcD.P?"
P*?d6v,r
/** T9&,v<f
* if(num<1) num=1 zzDNWPzsA
*/ e)fJd*P
publicvoid setNum(int num){ n#/U@qVgc
if(num < 1) h+ `J=a|\
num = 1; 5x93+DkO\
this.num = num; eUGmns
} HY@kw>I
R]V~IDs
/** Xuz8"b5^Zx
* 获得总页数 OgzGkc@A
*/ nA{ncTg1\
publicint getPageNum(){ ][T9IAn
return(count - 1) / num + 1; fJ|Bu("N
} 3"2<T^H]
n]kQtjJ
/** fS8XuT
* 获得本页的开始编号,为 (p-1)*num+1 _ d(Ks9
*/ k}+MvGq
publicint getStart(){ `"^@[1
return(p - 1) * num + 1; =PeW$q+
} N7Z(lI|a;
*IjdN,wox
/** ^Y*`D_-G
* @return Returns the results. f6(9wz$Trt
*/ O4'kS
@
publicList<E> getResults(){ q_%w
l5\F
return results; Y'+F0IZ+
} 8xeun~e"vS
Xm0&U?dZB
public void setResults(List<E> results){ oK(W)[u
this.results = results; N'Z_6A*-
} 4`EvEv$i
GT1 X
public String toString(){ CU7iva
StringBuilder buff = new StringBuilder j|VlHDqR
eX]9mQ]E
(); ,&O:/|c E
buff.append("{"); MFCbx>#
buff.append("count:").append(count); pX h^M{.
buff.append(",p:").append(p); 2yQ;lQ`
buff.append(",nump:").append(num); nFf\tf%8
buff.append(",results:").append Sf.8Ibw
p0:&7,+a,
(results); 4u{E D(
buff.append("}"); eF gb6dSh
return buff.toString(); 0YsN82IDD
} Xoa<r9
qNuv?.7
} $O8EiC!f6
eL]w' }\
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