Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 =4K:l}}
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 BKQwF*<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 L[MAc](me-
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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 n_4BNOZ~
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分页支持类: M>u84|`
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java代码: yXBWu=w3`O
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package com.javaeye.common.util; yH]w(z5Z
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import java.util.List; Aq_?8 Cd
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publicclass PaginationSupport { OhTd>~R`<
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publicfinalstaticint PAGESIZE = 30; >[4CQK`U
#|F5Kh"
privateint pageSize = PAGESIZE; :xC1Ka%~
*OHaqe(*
privateList items; LcGG~P|ML
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privateint totalCount; 3<}r+, j
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privateint[] indexes = newint[0]; ;qaNIOo9
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privateint startIndex = 0; oFp4*<\
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public PaginationSupport(List items, int 7kmd.<
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totalCount){ XT{ukEvDR
setPageSize(PAGESIZE); ij02J`w:Ra
setTotalCount(totalCount); 'v_k#%
setItems(items); XF`?5G~~#
setStartIndex(0); _o{w<b&
} I04c7cDp
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public PaginationSupport(List items, int Nj+gSa9
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totalCount, int startIndex){ ML:H\
setPageSize(PAGESIZE); Vs,
&
setTotalCount(totalCount); iV.j!H7o
setItems(items); E$s?)
setStartIndex(startIndex); $q0i=l&$&
} 1a'0cSH
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public PaginationSupport(List items, int a+P^?N
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totalCount, int pageSize, int startIndex){ Pk)H(,
setPageSize(pageSize); H+ 7Fw'u
setTotalCount(totalCount); YeVkX{y
setItems(items); >?r8D48`
setStartIndex(startIndex); ? ;$f"Wl
} 73kI%nNB
rl:D>t(:.
publicList getItems(){ eI=:z/pd
return items; R|-!5J4h
} A (ZtA[G
;oVFcZSA
publicvoid setItems(List items){ #>O+!IH
this.items = items; :$N{NChx
} 7loIjT7
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publicint getPageSize(){ 7o$S6Y;c4
return pageSize; rWN%Tai-
} }PxPJ$o
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publicvoid setPageSize(int pageSize){ )m>Y[)8!
this.pageSize = pageSize; '%KaAi$
} 9&'HhJm
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publicint getTotalCount(){ sQ8kLS_q8
return totalCount; mC./,a[
} b^WF
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publicvoid setTotalCount(int totalCount){ Q =4~uz|
if(totalCount > 0){ [ Ru( H
this.totalCount = totalCount; D[<~^R;*
int count = totalCount / lh*!f$2~
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pageSize; "eR-(c1
if(totalCount % pageSize > 0) `W'S'?$
count++; pu
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indexes = newint[count]; :zsMkdU
for(int i = 0; i < count; i++){ `f\+aD'u
indexes = pageSize * ,*g.?q@W2
ant#bDb/
i; d% Nx/DS)
} -E-e!
}else{ j&"GE':Y
this.totalCount = 0; ].3@ Dk
} s1
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} D@`"99z
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publicint[] getIndexes(){ 0hCUr]cZ,
return indexes; Z2&7HTz
} Ed>n/)Sm
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publicvoid setIndexes(int[] indexes){ Hzojv<c
this.indexes = indexes; IS%e5
} A\QrawBp0l
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publicint getStartIndex(){ ?xb2jZ/0X
return startIndex; tW"s^r=95
} |jyD@Q,4
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publicvoid setStartIndex(int startIndex){ XrN]}S$N
if(totalCount <= 0) vfOG(EkG.?
this.startIndex = 0; T,5(JP(h3
elseif(startIndex >= totalCount) *DPKV$
this.startIndex = indexes /|,:'W%U
6yhRcvJ}
[indexes.length - 1]; `{'h+v`
elseif(startIndex < 0) Zr$D\(hX
this.startIndex = 0; 06>+loBG
else{ PvVn}i
this.startIndex = indexes #gRtCoew
.MW/XnCYs4
[startIndex / pageSize]; ]QmY`pTB`
} 1owe'7\J
} Ct386j><
i
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publicint getNextIndex(){ ;Wig${
int nextIndex = getStartIndex() + '2v$xOh!y
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pageSize; -ei+r#
if(nextIndex >= totalCount) [<IJ{yfx
return getStartIndex(); L?r\J8Ch<
else ; 8u5
return nextIndex; uAv'%/
} l8RKwECdPn
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publicint getPreviousIndex(){ VpWpC&
int previousIndex = getStartIndex() - `&g1`vg
./Wi(p{F
pageSize; E9:p A5H-j
if(previousIndex < 0) yI8
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return0; Tizjh&*^
else Zksow} %
return previousIndex; 7:X@lmBz=
} bXK$H=S Bz
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} UszR. Z
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抽象业务类 x*0mmlCb
java代码: BnIZ+fg=
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/** 'cvc\=p
* Created on 2005-7-12 6|ENDd[
*/ psB9~EU&Q
package com.javaeye.common.business; =pn(56
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import java.io.Serializable; n^k Uu2g|
import java.util.List; W0KSLxM
E?F?)!%
import org.hibernate.Criteria; rI4N3d;C
import org.hibernate.HibernateException; _43 :1!os
import org.hibernate.Session; zq4)Uab*
import org.hibernate.criterion.DetachedCriteria; znu[i&\=
import org.hibernate.criterion.Projections; i`" L?3T
import JsbH'l
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org.springframework.orm.hibernate3.HibernateCallback; I>45xVA
import {b90c'8?a
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org.springframework.orm.hibernate3.support.HibernateDaoS p$bR M`R&s
;Ak 6*Sr
upport; dJUI.!hv;
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import com.javaeye.common.util.PaginationSupport; J7s\
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public abstract class AbstractManager extends N1jJ(}{3
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HibernateDaoSupport { Xsv^GmP+
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privateboolean cacheQueries = false; t7b\ #o
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privateString queryCacheRegion; $Qq5Fx9kU
9$e6?<`(Y
publicvoid setCacheQueries(boolean ]6TX)1
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cacheQueries){ -
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this.cacheQueries = cacheQueries; _33YgO
} _chX
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publicvoid setQueryCacheRegion(String
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queryCacheRegion){ ~h6aTN
this.queryCacheRegion = $sBje*;
TH#5j.uUs
queryCacheRegion; %<Kw
} N.qS;%*o{e
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publicvoid save(finalObject entity){ e6igx
getHibernateTemplate().save(entity); "ba>.h,#'
} y|[YEY U)
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publicvoid persist(finalObject entity){ rH5'+x K
getHibernateTemplate().save(entity); CHNIL^B
} _#rE6./@q
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publicvoid update(finalObject entity){ &P3ep[]j
getHibernateTemplate().update(entity); _!C'oG6s?
} Zlf)
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publicvoid delete(finalObject entity){ 6qp'
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getHibernateTemplate().delete(entity); _^cFdP)8|
} 6o^sQ(]
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publicObject load(finalClass entity, K18Sj,]B
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finalSerializable id){ o? {rPFR
return getHibernateTemplate().load 0xe*\CAo
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(entity, id); u&s>UkR
} /6a617?9J
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publicObject get(finalClass entity, 3tIno!|
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finalSerializable id){ 2%zJI"Ic
return getHibernateTemplate().get TBp$S=_**
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(entity, id); WnZn$N.
} sFWH*kdP?
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publicList findAll(finalClass entity){ YsXf+_._
return getHibernateTemplate().find("from @2Ca]2,4
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"BLbDZ@
" + entity.getName()); UO{3vry48
} ]@bu%_s"
@-F[3`HeA
publicList findByNamedQuery(finalString lL{1wCsl
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namedQuery){ !K319 eE
return getHibernateTemplate zM*PN|/%sH
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().findByNamedQuery(namedQuery); " .:b43Z
} `SGI
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publicList findByNamedQuery(finalString query, Zo(p6rku
}|!9aojr
finalObject parameter){ /~B\1
return getHibernateTemplate )/2J|LxS
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().findByNamedQuery(query, parameter); lf%Ju$H
} |<Gq^3 2
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publicList findByNamedQuery(finalString query, >[|Y$$
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finalObject[] parameters){ G'qGsKf\
return getHibernateTemplate cf
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().findByNamedQuery(query, parameters); )RE~=*?d
} o(_~
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publicList find(finalString query){ Xs7xZ$
return getHibernateTemplate().find K4>nBvZ?v
/,cyp.
(query); AD/7k3:
} yC<[LH
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publicList find(finalString query, finalObject 8rwXbYx
x
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parameter){ 4RXF.kJ3=
return getHibernateTemplate().find 5? rR'0
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(query, parameter); V0!.>sX9
} >u)DuZXj
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public PaginationSupport findPageByCriteria uk)6%
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(final DetachedCriteria detachedCriteria){ Sd0y=!Pj=
return findPageByCriteria 7,![oY[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); wmf#3"n
} ?()$imb*
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public PaginationSupport findPageByCriteria Jm(sx'qPx
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(final DetachedCriteria detachedCriteria, finalint #MhieG5
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startIndex){ bBC!fh!L"
return findPageByCriteria UPI'O %
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(detachedCriteria, PaginationSupport.PAGESIZE, V.k2t$@
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startIndex); l~v
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} 9/nS?>11
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public PaginationSupport findPageByCriteria R:LThFx
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(final DetachedCriteria detachedCriteria, finalint $sX X6K),
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pageSize, ~
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finalint startIndex){ !U2Wiks
return(PaginationSupport) IT~pp_6g
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getHibernateTemplate().execute(new HibernateCallback(){ 8aSH0dX
publicObject doInHibernate T)QT_ST.9
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(Session session)throws HibernateException { ;.g <u
Criteria criteria = p*^[
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detachedCriteria.getExecutableCriteria(session); &oyj8
int totalCount = sb7~sa&-
a.5^zq7#!
((Integer) criteria.setProjection(Projections.rowCount ~YX!49XfHh
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()).uniqueResult()).intValue(); Q41eYzAi
criteria.setProjection ]ZjydQjo)
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(null); l"-F<^
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List items = %?7j
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criteria.setFirstResult(startIndex).setMaxResults :$#";t|
9W[ ~c"Ku
(pageSize).list(); b2Jgg&?G
PaginationSupport ps = z^q ~|7
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new PaginationSupport(items, totalCount, pageSize, \D]H>i$
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startIndex); e{dYLQd
return ps; )|` #BC
} ny. YkN2
}, true); !VfP#B6.
} Cy~Pfty
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public List findAllByCriteria(final 3]X~bQAw
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DetachedCriteria detachedCriteria){ Po=@
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return(List) getHibernateTemplate YlY3C
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().execute(new HibernateCallback(){ ua^gG3n0
publicObject doInHibernate .>{.!a
#z*-
(Session session)throws HibernateException { Z\`i~
Criteria criteria = lR9~LNK?
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detachedCriteria.getExecutableCriteria(session); gUcG#
return criteria.list(); 9?
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} jo-qP4w
}, true); cS'|c06
} Yzr|Z7rq}
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public int getCountByCriteria(final @\=%M^bx
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DetachedCriteria detachedCriteria){ l9%oKJ;
Integer count = (Integer) }h6N.vz
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getHibernateTemplate().execute(new HibernateCallback(){ jE!W&0
publicObject doInHibernate >4zH\T!
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(Session session)throws HibernateException { AvN\^
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Criteria criteria = j^g^=uau
},2mIit(
detachedCriteria.getExecutableCriteria(session); !]W}I
return vB :_|B
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criteria.setProjection(Projections.rowCount 5F8sigr/h
FK$?8Jp
()).uniqueResult(); ZkyH<Aa
} o+H;ZGT5H
}, true); X"KX_)GZD
return count.intValue(); Y+k)d^6r
} U-P\F-
} em87`Hj^lo
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用户在web层构造查询条件detachedCriteria,和可选的 0<{+M` G/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 DL ^}?Ve
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PaginationSupport的实例ps。 @bN`+DC!<
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ps.getItems()得到已分页好的结果集 v Kzq7E
ps.getIndexes()得到分页索引的数组 .}}w@NO
ps.getTotalCount()得到总结果数 #'qEm=%
ps.getStartIndex()当前分页索引 USKa6<:{W
ps.getNextIndex()下一页索引 2qb,bp1$
ps.getPreviousIndex()上一页索引 ;xnJ+$//U
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Yy4?|wVl
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ?(cbZ#( o
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一下代码重构了。 @
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我把原本我的做法也提供出来供大家讨论吧: 7I/
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首先,为了实现分页查询,我封装了一个Page类: !H`! KBW
java代码: :
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/*Created on 2005-4-14*/ Mh04O@"
package org.flyware.util.page; &></l| hY
!$&3h-l[
/** 7b,5*]oZ
* @author Joa : QK )Ym
* qwlIz/j
*/ 7|A9
publicclass Page { FK
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/** imply if the page has previous page */ T@[(FVA N
privateboolean hasPrePage; OY'490
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/** imply if the page has next page */ /dU-$}>ZI
privateboolean hasNextPage; 69U[kW&
qM(n]{H
/** the number of every page */ D8otUDB{
privateint everyPage; T@PtO"r
WXqrx*?*+
/** the total page number */ uTNmt]
privateint totalPage; ;?/v}$Pa
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/** the number of current page */ r Bv
privateint currentPage; 6vVx>hFJ47
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/** the begin index of the records by the current K)|#FRPM u
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query */ $?^#G8J
privateint beginIndex; ?@"B:#l
#GBe=tm\K
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/** The default constructor */ ]XX8l:+
public Page(){ BJgg-z{Y
IS;F9{
} [KIK}:
_y Q*
/** construct the page by everyPage Pdc- 3
* @param everyPage p?OwcMT]M
* */ nwlo,[
public Page(int everyPage){ Y[=Gv6Fr
this.everyPage = everyPage; S/j~1q_|G
} 8U8l
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/** The whole constructor */ $9v:(:!Bm
public Page(boolean hasPrePage, boolean hasNextPage, y6|&bJ @
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=(kwMJ
int everyPage, int totalPage, (>*<<a22
int currentPage, int beginIndex){ JO:40V?op
this.hasPrePage = hasPrePage; k^3|A3A
this.hasNextPage = hasNextPage; 5}3Q}o#
this.everyPage = everyPage; 38IVSK_
this.totalPage = totalPage; #t
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this.currentPage = currentPage; {K-]nh/
this.beginIndex = beginIndex; 9Ny{2m=Ye
} \~4uEk"]
V#;6<H"
/** H
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* @return &P>wIbE
* Returns the beginIndex. k>
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*/ ' bio:1
publicint getBeginIndex(){ HH[b1z2D
return beginIndex; (`}O!;/E}
} .@#i
" &B/v"nj
/** ,fQc0gM=[
* @param beginIndex lc/q0
* The beginIndex to set. {6YLiQ*_
*/ Yr@)W~
publicvoid setBeginIndex(int beginIndex){ Y|FJ1x$r
this.beginIndex = beginIndex; l^x5m]Kt
} DXj_\ R(}
S_cba(0-|\
/** MF/359r)Et
* @return Ob+L|FbnN
* Returns the currentPage. EB'(%dH
*/ 24_F`" :-=
publicint getCurrentPage(){ g_Wf3o857J
return currentPage; 8M m,a
} S/CT;M@W
"WOY`su>
/** Pb$ep|`u
* @param currentPage 0R~{|RHM
* The currentPage to set. 7MreBs(M
*/ ,o-BJ
069
publicvoid setCurrentPage(int currentPage){ s$e0;C!D
this.currentPage = currentPage; +D|y))fE
} Rt{qbM|b&
yu~~"Rq)
/** W!g'*L/#L
* @return BgLK}p^
* Returns the everyPage. tE/s|v#O
*/
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publicint getEveryPage(){ E<;C@B
return everyPage; gc@,lNmi
} jj8AV lN
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/** P`wp`HI
* @param everyPage kBd #=J
* The everyPage to set. T!eb=oy
*/ Jq) !)={
publicvoid setEveryPage(int everyPage){ ;Dg8>
this.everyPage = everyPage; {,p<!Jq~G
} 5DKR1z:
s
bV6}
/** v/6QE;BY&Q
* @return 7>`QX%
* Returns the hasNextPage. \3w=')({
*/ n'ft@7>%h
publicboolean getHasNextPage(){ {'8a'9\
return hasNextPage; eS9/-Y
} S5]rIcM
weC$\st:D
/** :M(%sv</
* @param hasNextPage w~sr2;rp<
* The hasNextPage to set. PNgj 8J4
*/ ZiodJ"r
publicvoid setHasNextPage(boolean hasNextPage){ X<J
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this.hasNextPage = hasNextPage; FQSepUl
} vsg"!y@v
4;8
Z?.
/** C#X|U2$
* @return =if5$jE3
* Returns the hasPrePage. OL&ku &J_
*/ L2Uk/E
publicboolean getHasPrePage(){ TGu`r>N51
return hasPrePage; W@jBX{k
} g!5`R`7
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/** Zuod1;qIh
* @param hasPrePage aB~?Y+m
* The hasPrePage to set. ;,n{6`
*/ H
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publicvoid setHasPrePage(boolean hasPrePage){ 9r%O
this.hasPrePage = hasPrePage; <e|I?zI9-
} {Cnz7TVB
-sl]
funRy
/** 7u-o7#,X2
* @return Returns the totalPage. !Q=H)\3
* +/*,%TdQ4
*/ bCHA!zO
publicint getTotalPage(){ +4EQ9 -
return totalPage; ve_TpP
} VqLqj$P
;_),?(
/** h\afO
* @param totalPage K"-.K]O8E%
* The totalPage to set. <zH24[
*/ fQq'_q5
publicvoid setTotalPage(int totalPage){
?"[b408-
this.totalPage = totalPage; u-0-~TwD
} !\.x7N<)0
*j RNpB{)z
} UOy9N
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_] veTAV
oVyOiWo\Z
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 Z?Y14L~%
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个PageUtil,负责对Page对象进行构造: ,-#8/9ts
java代码: !8M]n
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/*Created on 2005-4-14*/ hb'S!N5m
package org.flyware.util.page; &m_4#
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import org.apache.commons.logging.Log; \wqi_[A
import org.apache.commons.logging.LogFactory; {Sm^F
Vr0-evwfo
/** pTPWToKh
* @author Joa -Zd0[& ']
* E'zLgU)r`
*/ {(#Dou
publicclass PageUtil { H'Q4IRT
5%j
!SVW
privatestaticfinal Log logger = LogFactory.getLog `)$'1,]u
G4][`C]8c
(PageUtil.class); :786Z,')
-t2bHhG
/** ?]SSmZpk
* Use the origin page to create a new page &u0JzK
* @param page HTuv_kE
* @param totalRecords 4`Qu+&4J
* @return $Kn{x!,"(
*/ aaW(S K
publicstatic Page createPage(Page page, int 6tBL?'pG
C;#vW FE
totalRecords){ $lmGMljF
return createPage(page.getEveryPage(), Ge=+0W)&
(<!Yw|~
page.getCurrentPage(), totalRecords); jC7`_;>=
} 9q;n@q:29
qV2aa9p+
/** B*#lkMr
* the basic page utils not including exception t=\y|Idc
daS l.:1
handler &y"e|aE
* @param everyPage gSS2)Sd}
* @param currentPage 6? u9hi
* @param totalRecords ~ {OBRC
* @return page A]^RV{P
*/ L5 ~wX
publicstatic Page createPage(int everyPage, int Kt5;GUV
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currentPage, int totalRecords){ <Uf?7
everyPage = getEveryPage(everyPage); ^"N]i`dIF
currentPage = getCurrentPage(currentPage); W=j
int beginIndex = getBeginIndex(everyPage, H.#<&5f
R@_i$Df|
currentPage);
c+P.o.k;
int totalPage = getTotalPage(everyPage, K1]m:Y<
Obwj=_+upd
totalRecords); -)_"7}|u5
boolean hasNextPage = hasNextPage(currentPage, _GSl}\
,x#5 .Koz
totalPage); YJi C}.4Q
boolean hasPrePage = hasPrePage(currentPage); ]/>(C76
iQs7Ly"
returnnew Page(hasPrePage, hasNextPage, #5*|/LD
everyPage, totalPage, J_) .Hd
currentPage, d2f
Bbk=0+ ^8I
beginIndex); a(-
^ .w
} C{7
j<O
Kppi
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privatestaticint getEveryPage(int everyPage){ eP6`"<UM
return everyPage == 0 ? 10 : everyPage; /, T@/
} uR#aO''
@}sxA9a
privatestaticint getCurrentPage(int currentPage){ ^p3"_;p)h
return currentPage == 0 ? 1 : currentPage; b7&5>Q/g
} t@dv$W2
"
p2Yc:9r9+A
privatestaticint getBeginIndex(int everyPage, int (Q~ p"Ch
8{QN$Qkn
currentPage){ |/rms`YQ
return(currentPage - 1) * everyPage; )xKZ)SxV
} }U-h^x'
Z_^i2eJYT
privatestaticint getTotalPage(int everyPage, int K]5@bm
;la sk4|
totalRecords){ rt- ^?2c?
int totalPage = 0; mOm_a9ML
ro:B[XE
if(totalRecords % everyPage == 0) M@\A_x(Mas
totalPage = totalRecords / everyPage; ?Ybgzb
else x,)|;HXm
totalPage = totalRecords / everyPage + 1 ; )nncCUW
Rs*]I\
return totalPage; 4#j W}4C{
} aPD4S&"Q
|T!ivd1G
privatestaticboolean hasPrePage(int currentPage){ z^;0{q,
return currentPage == 1 ? false : true; }.bhsy
} h0i/ v
@ Gxnrh6
privatestaticboolean hasNextPage(int currentPage, PL*Mz(&bf
tCZ3n
int totalPage){ c;X8:Z=ja
return currentPage == totalPage || totalPage == tkQ#mipAj
&z'NQ!uV
0 ? false : true; LHit9O[_/s
} &d1|B`gL|
gl k-: #
y; oPg4
} :zN{>,sC
XEK% \o}
T["(wPrt
8n_!WDD
954!ED|F(
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。 v[-.]b*5A$
tb#9TF
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 LBO3){=J
cOz8YVR-
做法如下: ~=xiMB;oH
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 W@"s~I6
Fog4m=b`g
的信息,和一个结果集List: "gaurr3
java代码: $hND!T+;
;/hR#>ib
:!',o]"4,k
/*Created on 2005-6-13*/ q.xt%`@aA
package com.adt.bo; ~8fy
qE$
7sgK+
ip
import java.util.List; wlSl ~A/s
Q7V*~{
import org.flyware.util.page.Page; kBF.TGT[l
/#WRd}IjK
/** a| w.G "W
* @author Joa ^tp6G
*/ (T&rvE
publicclass Result { j`
RuK
uP;qs8
private Page page; R;XG2
)(^L*
private List content; l:' 0
,q[aV 6kO
/** \&[Jtv *
* The default constructor }02#[vg
*/ nw.,`M,N
public Result(){ I%4)%
super(); nYA@t=t0
} vIMLUL0
|->P|1
P
/** `Mg&s*
* The constructor using fields 3u&>r-V6Fn
* *?l-:bc]
* @param page $C&y-Hnar
* @param content H]zi>;D
*/ 6R`q{}.
public Result(Page page, List content){ DL*/hbG
this.page = page; J #ukH`|-
this.content = content; 9YMD[H\}V
} bQTkW<7gh
nu=yE$BN{
/** Nj p?/r
* @return Returns the content. O1C|{
M
*/ *#{V^}
publicList getContent(){ \Uz7ar#,
return content; 6!QY)H^j9,
} /=y _#l
(vO\h8
/** @^O+ulLJ,]
* @return Returns the page. }KEL{VUX
*/ 2cnyq$4k
public Page getPage(){ j'\!p):H
return page; %$'YP
} {Yt@H
\w6A-daD0
/** Z30r|Ufh
* @param content G8sxg&bf{
* The content to set. ygN4%-[XA
*/ WUN|,P`b
public void setContent(List content){ \vKKq/f
this.content = content; -gq,^j5,
} |(evDS5
F]fBFDk
/** .m;5s45O{
* @param page r2h{#2
* The page to set. vV( ?A
*/ WVa-0;
publicvoid setPage(Page page){ O7})1|>1
this.page = page; i(hL6DLD
} p-qt?A
} mFGiysM
DI>SW%)>
8lNkY`P7s
3EVAB0/$
U8||)+
2. 编写业务逻辑接口,并实现它(UserManager, VGe OoS
$\9M6k'
UserManagerImpl) CogN1,GJ
java代码: +N3f{-{"Yo
X~o6Xkg
Rr% CP[bH
/*Created on 2005-7-15*/ =sIkA)"!=
package com.adt.service; -wdd'G
X5Fi
, /H
import net.sf.hibernate.HibernateException; 5`3Wua
>508-)'
import org.flyware.util.page.Page; :(?F(Q^
Y!1x,"O'H
import com.adt.bo.Result; =Z(_lLNmh
H1fKe=$1
/** ab!Cu8~v
* @author Joa i(9 5=t(
*/ n2p(@
publicinterface UserManager { I@M3u/7
flXDGoW
public Result listUser(Page page)throws V Kw33
57S!X|CE
HibernateException; kGkfLY6B
810pJ
} -^f>=xa4J
}2!=1|}
zm{U.Q
zF7*T?3b"
k^i\<@v
java代码: YqEB%Y~N+
R2Y.s^
C25EIIdRb
/*Created on 2005-7-15*/ vMHJgpd&j
package com.adt.service.impl; sI OT6L^7
{;2Gl $\r
import java.util.List; D=^|6}
i^Ip+J+[
import net.sf.hibernate.HibernateException; kp=wz0#
)J>-;EYb8
import org.flyware.util.page.Page; 9e _8Z@|
import org.flyware.util.page.PageUtil; Qk)E:
aS3Fvk0R{h
import com.adt.bo.Result; ,| Zkpn8
import com.adt.dao.UserDAO; |ZmWhkOX
import com.adt.exception.ObjectNotFoundException; ;) (F4
import com.adt.service.UserManager; ej;\a:JL
1${rQ9FIF
/** >S[NI<=8S
* @author Joa 7,IH7l|G
*/ C?h}n4\B^?
publicclass UserManagerImpl implements UserManager { aBblP8)8;K
D>`lN
private UserDAO userDAO; \pwg8p[4Q
IPDQ
/** qi]"`\
* @param userDAO The userDAO to set. ;X}!;S%K
*/
?}Y;/Lwx
publicvoid setUserDAO(UserDAO userDAO){ 6p)dO
c3L
this.userDAO = userDAO; @ |^;d
} Ni
Y.OwKr
%h^ f?.(:
/* (non-Javadoc) NN"!kuM
* @see com.adt.service.UserManager#listUser k@=w? m
'>U&B}
(org.flyware.util.page.Page) c>)_ I
*/ ?Mj@;O9>'
public Result listUser(Page page)throws .ZVADVg\
SMMvRF`7
HibernateException, ObjectNotFoundException { i!7|YAu
int totalRecords = userDAO.getUserCount(); x:0nK,
if(totalRecords == 0) 1b LY1
throw new ObjectNotFoundException [R%Pf/[Fr
Ra-%,cS
("userNotExist"); RKtU@MX49
page = PageUtil.createPage(page, totalRecords); %kXg|9Bx!
List users = userDAO.getUserByPage(page); Y| 2Gj(*8
returnnew Result(page, users); 5m\T~[`%
} +m]Kj3-z@
gu|cQ2xV
} fZNWJo# `.
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NA-)7i*>J
{[Z}<#n)
I?~iEO\nh
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ;cfmMt!QWJ
aS)Gj?Odf
询,接下来编写UserDAO的代码: NB#-W4NA
3. UserDAO 和 UserDAOImpl: syB.Z-Cpd
java代码: 2)^gd
Dqg~g|(Q<
G\ m`{jv
/*Created on 2005-7-15*/ i8+[-mh
package com.adt.dao; tO8<N'TD
/5&'U!:+
import java.util.List; 7
yp}
*)82iD
import org.flyware.util.page.Page; 12y+g5b
:J~sz)n4
import net.sf.hibernate.HibernateException; N[j*Q 8X_
a%NSL6
/** pe@j`Sm:Ej
* @author Joa 9LK<u $C
*/ ["}Yp
publicinterface UserDAO extends BaseDAO { ITr@;@}c]
kr{eC/Q"
publicList getUserByName(String name)throws J{qpGRQNa
m)oGeD( !
HibernateException; G~FAChI8![
sUTfY|<7|
publicint getUserCount()throws HibernateException; *-lw2M9V
"&{sE RYY
publicList getUserByPage(Page page)throws am(jmf::
]<g`rR7}
HibernateException; t/Y)% N
s:f%=4-7
} )DwHLaLW
@yxF/eeEy+
8D5v'[j-
0k):OVfm=
:o=a@Rqx
java代码: TW)~&;1l
kD{qW=Lpn
_=ziw|zI
/*Created on 2005-7-15*/ w\(;>e@
package com.adt.dao.impl; Xn3
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x!^u$5c
import java.util.List; 4pG!m&4]ze
n"dYN3dE
import org.flyware.util.page.Page; H=1Jq
5A`T}~"X
import net.sf.hibernate.HibernateException; V^/]h
u
import net.sf.hibernate.Query; p*OpO&oodu
<o:|0=Swb
import com.adt.dao.UserDAO; n7*.zI]%&
DVLF8]5
/** t
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* @author Joa ai@hQJ*
*/ l?J|Ip2W
public class UserDAOImpl extends BaseDAOHibernateImpl WIkr0k
D
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implements UserDAO { ZGZ+BOFL
#!RO,{FT
/* (non-Javadoc) N}5'Hk4+
* @see com.adt.dao.UserDAO#getUserByName VyWPg7}e
dSq3V#Q
(java.lang.String) .Mz'h9@
*/ X|wg7>kh*`
publicList getUserByName(String name)throws JVawWw0q
H){lXR/#u
HibernateException { )"4v0dv
String querySentence = "FROM user in class 29~Bu5
.^aqzA=]
com.adt.po.User WHERE user.name=:name"; u{d\3-]/
Query query = getSession().createQuery W &HF*Aw
jGaI6G'N
(querySentence); lk`,s
query.setParameter("name", name); ),;O3:n
return query.list(); 8DO3L
"
} ;[R#:Rk
[Z$E^QAP
/* (non-Javadoc) \\{+t<?J
* @see com.adt.dao.UserDAO#getUserCount() RZrQ^tI3"
*/ Y24H`
s1u/
publicint getUserCount()throws HibernateException { OS7^S1r-
int count = 0; E
whCX'Vaj
String querySentence = "SELECT count(*) FROM
SdM@7%UK
71(C@/J
user in class com.adt.po.User"; ?@LqrKj11
Query query = getSession().createQuery \2huDNW&
!
X^c2
(querySentence); (>usa||
count = ((Integer)query.iterate().next ^j>w<ljzz
TeXt'G=M
()).intValue(); /lqVMlz\77
return count; n,vs(ZL:
} ?X5Y8n]y\h
}=T=Z#OgH
/* (non-Javadoc) `iT{H]po
* @see com.adt.dao.UserDAO#getUserByPage s%xhT
e_Un:r@)
(org.flyware.util.page.Page) @?E|]H!S]
*/ lS!uL9t.
publicList getUserByPage(Page page)throws %{*)-_M
.lE7v -e
HibernateException { UD}#c:I
String querySentence = "FROM user in class Z:3SI$tO
Ptj[9R
com.adt.po.User"; rmh 1.W
Query query = getSession().createQuery wM
aqR"%
k 3S
(querySentence); I2G:jMPy
query.setFirstResult(page.getBeginIndex()) 4t e QG
.setMaxResults(page.getEveryPage()); bWEti}kW
return query.list(); ;I@@PUnR
} h#o?O k
\[yg f6#[
} DLBHZ?+!
C0v1x=(xiM
(#?k|e"Y"`
X+LG Z4]D
R m^$Dn
至此,一个完整的分页程序完成。前台的只需要调用 5@&{%99
& Y Y^Bd#
userManager.listUser(page)即可得到一个Page对象和结果集对象 S%{^@L+V
o{r<=X ysM
的综合体,而传入的参数page对象则可以由前台传入,如果用 RW I7eC
#ssSs]zl
webwork,甚至可以直接在配置文件中指定。 jS<(Oo
%f'mW2
下面给出一个webwork调用示例: (]gd$BgD
java代码: :+*q,lX8
TVs#,
3I):W9$Qp
/*Created on 2005-6-17*/ eF=cMC
package com.adt.action.user; IVdM}"+
9hn+eU
import java.util.List; ExKjH*gn
8DLj?M>N
import org.apache.commons.logging.Log; 5%)<e-
import org.apache.commons.logging.LogFactory; HmQ.'
import org.flyware.util.page.Page; qGVf!R
+p"}F PIK
import com.adt.bo.Result; mJN*DP{
import com.adt.service.UserService; H.=S08c3kA
import com.opensymphony.xwork.Action; g*]/HS>e<G
0tb%h[%,M
/** +0Z,#b
* @author Joa J,SP1-L
*/ ]q pLaBD
publicclass ListUser implementsAction{ e:uk``\
~dz,eB
privatestaticfinal Log logger = LogFactory.getLog 2uZ4$_
R q
|,@
(ListUser.class); {Uj-x
-
)F,IPAA#
private UserService userService; nkTpUbS'f?
u(W+hdTap=
private Page page; wY'w'%A?
?_V&~?r
privateList users; 1XXuFa&
uw>O|&!
/* e !2SO*O
* (non-Javadoc) orON)Sks
* qSA]61U&
* @see com.opensymphony.xwork.Action#execute() l.nd Wv
*/ CyXFuk!R
publicString execute()throwsException{ 'nRoa7v(
Result result = userService.listUser(page); 0 *^>/*
page = result.getPage(); EJ@&vuDd$
users = result.getContent(); J1UG},-h
return SUCCESS; 50jZu'z:
} )Gm,%[?2C
0(|Yy/Yq
/** rHaj~s 4
* @return Returns the page. )sZJH9[K
*/ !%X#;{
public Page getPage(){ :tf'Gw6v
return page; 6m$lK%P{1
} MP_LdJM1E
[L ?^+p>
/** q"9 2][}
* @return Returns the users. h
]6:`5-
*/ H~:EPFi.(
publicList getUsers(){ N5d)&a
7?
return users; gzd<D}2F~
} Kg6[
e%_J
O7
/** OaeX:r+&Q
* @param page AEd]nVV Q
* The page to set. ?RQ_LA;
*/ |5TzRz
publicvoid setPage(Page page){ NpLZ
,|H
this.page = page; 38E
%]*5F
} ;_p$5GVR|
w&[&ZDsK
/** ;V0^uB.z
* @param users W"n0x8~sV
* The users to set. c]%~X&Tg`
*/ w<&R|= 93
publicvoid setUsers(List users){ K;Fs5|gFU
this.users = users; lW|`8ykp
} W+Q^u7K
SxI-pH'
/** kt2W7.A5
* @param userService zI,z <-
* The userService to set. <BiSx
*/ V|&->9"
publicvoid setUserService(UserService userService){ Ji)Ys
ebV
this.userService = userService; c> 0R_
} 363KU@`
} e|}B;<
B",;z)(%
|i\%>Y,
["^? vhv
b.j$Gna>Q
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, dym K @
8I[=iU7]l
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 Ef$a&*)PH
FDal;T
么只需要: Ggk#>O G
java代码: `0, G'F
t>!Ok
E?-
~*T
<?xml version="1.0"?> HA74s':FN
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 0[]) wl
V+5av Z}
1.0//EN" "http://www.opensymphony.com/xwork/xwork- v`@M IOv
i__f%j`!W
1.0.dtd"> ,@kLH"a0
> JC"YB
<xwork> l;d4Le
C#LTF-$])
<package name="user" extends="webwork- />n!2'!
`a `>Mtl
interceptors"> yV*jc`1
|Iknk,
<!-- The default interceptor stack name kvG.?^ v
{l"(EeW6)
--> uaE,F^p
<default-interceptor-ref rf+Z0C0WYi
hdeI/4 B
name="myDefaultWebStack"/> `ZU]eAV
iNr&;
<action name="listUser" ,N1pw w?
GkpYf~\Q
class="com.adt.action.user.ListUser"> n^|SN9_r
<param l
>~Rzw
=o4gW`\z
name="page.everyPage">10</param> \%&):OD1
<result D"gv:RojD
C8W_f( i~
name="success">/user/user_list.jsp</result> xXlx}C
</action> `S+n,,l
iJH?Z,Tjf
</package> g/frg(KF
;nrkC\SYh:
</xwork> t$
97[ay
*q"1I9zvT
G.r .Z0
gO{$p q}
cJf&R^[T
)t((x
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 l9e=dV:pH
9k\M<jA
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ~)F_FS
osc A\r
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 fZoQQ[s
[dFe-2u ,$
\l%##7DRp]
a6@k*9D>
|8tKN"QG
我写的一个用于分页的类,用了泛型了,hoho =YIosmr
# [
+n(
java代码: #&ei
+IMt$}7[
,`PYU[
package com.intokr.util; ht#,v5oG>f
EeHghq
import java.util.List; @Ko#nDEq
%k<+#j6ZH
/** 39MOqVc
* 用于分页的类<br> 5g.w"0MkY
* 可以用于传递查询的结果也可以用于传送查询的参数<br> qHgzgS7a
* Kn1T2WSAg
* @version 0.01 `6RccEm
* @author cheng TqSjL{l%
*/ X#Ob^E%J
public class Paginator<E> { Qsw.429t
privateint count = 0; // 总记录数 V CVKh
privateint p = 1; // 页编号 nch#DE82
privateint num = 20; // 每页的记录数 Khl0 ~
privateList<E> results = null; // 结果
1/,~0N9
L)8%*X
/** U_hzSf
* 结果总数 g6+5uvpd
*/ F("|SOhc
publicint getCount(){
AQ0zsy
return count; =J"c'Z>.
} zK I1
JP(0/?Q
publicvoid setCount(int count){ W7;RQ
this.count = count; YI;MS:Qj
} 6Eus_aP
>3*a&_cI=k
/** ~1aM5Ba{
* 本结果所在的页码,从1开始 8)2M%R\THn
* OO'zIC<z
* @return Returns the pageNo. A2p% Y},
*/ C9_[ke[1D
publicint getP(){ xB]^^NYE=
return p; a_]l?t
} CMyz!jZ3
#2lvRJB
/** +=d=
* if(p<=0) p=1 11k}Ly
* B~M6l7^?
* @param p =p7id5"
*/ XL9-N?(@
publicvoid setP(int p){ fQwLx
if(p <= 0) \/C5L:|p_
p = 1; wCV~9JTJ!
this.p = p; cnRgzj<ek
} bvHQ #:}H
bR1Q77<G\
/** 7F_N{avr
* 每页记录数量 kZ]pV=\Y*
*/ ur7S
K(#
publicint getNum(){ (Q&O'ng1
return num; @6%7X7m
} 7z&$\qu2
mi7~(V>
/** KfYT
* if(num<1) num=1 v T
@25
*/ g3yZi7b5FU
publicvoid setNum(int num){ Gm3`/!r
if(num < 1) B#}EYY
num = 1; mxu !$wx
this.num = num; 2[j`bYNe
} lA;qFXaN>
K`60[bdp
/** ];5Auh0o
* 获得总页数 (9=E5n6o
*/ /1D.Ud^
publicint getPageNum(){ i) Q
d>(v
return(count - 1) / num + 1; G'';VoW=
} 0P{8s
"!fwIEG
/** ;g;1<?
[
* 获得本页的开始编号,为 (p-1)*num+1 LU8:]zOY
*/ ^QG<_Dm]
publicint getStart(){ aR'~=t&;z1
return(p - 1) * num + 1; /d/]#T[Z9
} i2;,\FI@t%
86!$<!I
/** VR%*8=
* @return Returns the results. ,rF!o_7
*/ G:wO1f6
publicList<E> getResults(){ 3OY(L`
return results; p:eaZ
} "q!*RO'a
l8 $.k5X
public void setResults(List<E> results){ \qlz<
this.results = results; vlipB}
} c/:k|x
\m1^sFMZ
public String toString(){ y+V>,W)r7
StringBuilder buff = new StringBuilder XW\
3t tx
4Ss y (gt
(); pp{GaCi
buff.append("{"); 3`RI[%AN~
buff.append("count:").append(count); G )`gn
buff.append(",p:").append(p); 3+
2&9mm
buff.append(",nump:").append(num); wehiX7y
buff.append(",results:").append Ts|;5ya5m
[-81s!#mkw
(results); W^S]"N0u
buff.append("}"); &&m1_K
return buff.toString(); )K`tnb.Pf
} Pj_DI)^
f^F"e'1
} !R#PJH/TM
sIl&\g<b
h(3-/4