Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 fJv0 B*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pq5)Ug
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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 Lu:!vTRmw
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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 @=wAk5[IN
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分页支持类: D~f.)kkC4
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java代码: RAE|eTnna
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package com.javaeye.common.util; M/V
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import java.util.List; 3"[ KXzn
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publicclass PaginationSupport { <i`EP/x
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publicfinalstaticint PAGESIZE = 30; !.t'3~dUf$
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privateint pageSize = PAGESIZE; nBiSc*
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privateList items; U}A+jJ
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privateint totalCount; 6C]!>i}U
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privateint[] indexes = newint[0]; _ux6SIyp`
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privateint startIndex = 0; b!.# `.
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public PaginationSupport(List items, int W>@%d`>o5
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totalCount){ RM<\bZPc
setPageSize(PAGESIZE); M2xUs
setTotalCount(totalCount); bkOm/8k|4
setItems(items); 5 #kvb$97
setStartIndex(0); !d(!1fC
} g<.8iW 'c
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public PaginationSupport(List items, int It_yh
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totalCount, int startIndex){ %!.rP
setPageSize(PAGESIZE); T@Q<oNU
setTotalCount(totalCount); B!tte)
setItems(items); p>}N9v;Bo
setStartIndex(startIndex); gwqK`ww
} +mxYz#reX
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public PaginationSupport(List items, int ONfJ"Rp3
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totalCount, int pageSize, int startIndex){ JnsXEkM)
setPageSize(pageSize); gSe{S
setTotalCount(totalCount); moo>~F _^
setItems(items); mmjB1L
setStartIndex(startIndex); t!i F(R\
} wUV%NZB
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publicList getItems(){ 8 Zj>|u
return items; 73<iK]*c
} qJ!oH&/cD
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publicvoid setItems(List items){ [&`>&u@MK
this.items = items; =:0(&NCRq
} r2Z`4tN:
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publicint getPageSize(){ pF !vW
return pageSize; *{Z!m@?
} Y
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publicvoid setPageSize(int pageSize){ qnm9Lw#
this.pageSize = pageSize; 3}gK`1Nq1
} AN1bfF:C
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publicint getTotalCount(){ ``z="oD
return totalCount; 0,3 ':Df
} dk]ro~ [
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publicvoid setTotalCount(int totalCount){ VN".NEL
if(totalCount > 0){ ^}[
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this.totalCount = totalCount; jXDo!a|4y
int count = totalCount / {vH8X(m
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pageSize; Z)&HqqT3p
if(totalCount % pageSize > 0) a|53E<5X
count++; r 1a{Y8?
indexes = newint[count]; j,-7J*A~
for(int i = 0; i < count; i++){ F>Oh)VL,Ev
indexes = pageSize * ~VGK#'X:
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i; [*<&]^
} VA%i_P,
}else{ 0q;] ;m
this.totalCount = 0; 7U7 i2 4
} t8+93,*B
} E,$uNw ']
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publicint[] getIndexes(){ )K6{_~Kc\
return indexes; '[E_7$d
} xr2:bu
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publicvoid setIndexes(int[] indexes){ #lC{R^SL
this.indexes = indexes; x M[#Ah)
} \*
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publicint getStartIndex(){ ?!66yn
return startIndex; ou-;k
}
} /W>"G1)
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publicvoid setStartIndex(int startIndex){ ?n+\T'f!
if(totalCount <= 0) q<8HG_
this.startIndex = 0; Z}C%%2Iz
elseif(startIndex >= totalCount) aKy|$
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this.startIndex = indexes %G&v@R
Ne EV!V8
[indexes.length - 1]; fpi6pcof
elseif(startIndex < 0) Q!{Dw:7
this.startIndex = 0; )1,&YJM*6l
else{ cOgtBEhn
this.startIndex = indexes iy"Kg]
]*h}sn=
[startIndex / pageSize]; ATHz~a
} [)pT{QA
} k}.nH"AQ
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publicint getNextIndex(){ [ub\DLl
int nextIndex = getStartIndex() + \nWpV7TSN
p'4P2
pageSize; A&'%ou
if(nextIndex >= totalCount) &O,$l3 P
return getStartIndex(); ZB%~>
else D=vq<X'
return nextIndex; 2cl~Va=
} CQ[-Cp7
6KG 63`aQ
publicint getPreviousIndex(){ WGx>{'LJ
int previousIndex = getStartIndex() - #w@Pa L iS
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pageSize; Z(eSnV_RL
if(previousIndex < 0) NZ5~\k
return0; nE;gM1I
else ?OyW|jL
return previousIndex; IycxRig
} ,gc#N
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} WU\bJ}
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抽象业务类 /f<(K-o]
java代码: i#=X#_
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/** #O+]ydvT
* Created on 2005-7-12 #^ #i]{g
*/ ZB&Uhi
package com.javaeye.common.business; Rp*t"HSaAW
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import java.io.Serializable; jYz3(mM'J
import java.util.List; )}!'VIe^!
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import org.hibernate.Criteria; uek3Y[n
import org.hibernate.HibernateException; G |^X:+
import org.hibernate.Session; |GQ$UB
import org.hibernate.criterion.DetachedCriteria; |lwN!KVQ,
import org.hibernate.criterion.Projections; !ei20@
import fZfiiE~7J
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org.springframework.orm.hibernate3.HibernateCallback; %U7f9
import 4/WCs$
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org.springframework.orm.hibernate3.support.HibernateDaoS 2v1&%x:y#
8-ssiiJ}gh
upport; *XOKH+_u
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import com.javaeye.common.util.PaginationSupport; h';v'"DoW`
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public abstract class AbstractManager extends nn:pf1
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HibernateDaoSupport { gDNW~?/
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privateboolean cacheQueries = false; s[4!R&b
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privateString queryCacheRegion; qXGLv4c`Q
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publicvoid setCacheQueries(boolean OZm[iH
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cacheQueries){ s'Gy+h.
this.cacheQueries = cacheQueries; }{oBKm9_p
} _PXo'*j
5q`)jd !*)
publicvoid setQueryCacheRegion(String *+4iBpyiB
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queryCacheRegion){ 5udoZ>T
this.queryCacheRegion = F$p*G][
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queryCacheRegion; _
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} RpP[ymMZJ
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publicvoid save(finalObject entity){ Bjj^!T/#
getHibernateTemplate().save(entity); P.Z<b:V!
} 1/+r?F3
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publicvoid persist(finalObject entity){ r~_ /Jj
getHibernateTemplate().save(entity); an[~%vxw}
} J4c 4Os>3
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publicvoid update(finalObject entity){ 4S9,
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getHibernateTemplate().update(entity); ,nRwwFd.
} l]y%cJ~$'D
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publicvoid delete(finalObject entity){ GSnHxs)
getHibernateTemplate().delete(entity); v^_]W3K
} bvS\P!m\c
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publicObject load(finalClass entity, ,<r 3Z$G
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finalSerializable id){ SJ7=<y}[d
return getHibernateTemplate().load <?Izfl6
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(entity, id); KqUSTR1e[
} |P0L,R
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publicObject get(finalClass entity, NZW)X[nXM
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finalSerializable id){ XfK.Fj~-
return getHibernateTemplate().get *Q120R
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(entity, id); <O)X89dFM
} fA0=Y,pzv
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publicList findAll(finalClass entity){ #]a51Vss
return getHibernateTemplate().find("from vek:/'sj3p
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" + entity.getName()); IBNQmVRrI
} TIWLp
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publicList findByNamedQuery(finalString *([)X2A@+
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namedQuery){ lrX0c$)
return getHibernateTemplate 't?7.#,6O
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().findByNamedQuery(namedQuery); v[DbhIXU
} 8|qB1fB
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publicList findByNamedQuery(finalString query, nC.2./OwMf
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finalObject parameter){ =*:_swd
return getHibernateTemplate !"x7re
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().findByNamedQuery(query, parameter); ?r E]s!K
} {$1$]p~3o
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publicList findByNamedQuery(finalString query, IgR"euU
"zIq)PY
finalObject[] parameters){ D62
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return getHibernateTemplate <6O_t,K]
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().findByNamedQuery(query, parameters); kxqc6
} r{2].31'
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publicList find(finalString query){ ie~fQ!rf
return getHibernateTemplate().find h k!,
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(query); .0fh>kQ
} hB}h-i(u
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publicList find(finalString query, finalObject SM#S/|.]
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parameter){ /`O]etr`d
return getHibernateTemplate().find m":SE? {{&
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(query, parameter); G!VF*yW8
} u!3]RGJ
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public PaginationSupport findPageByCriteria $FusDdCv3
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(final DetachedCriteria detachedCriteria){ {29S`-|P
return findPageByCriteria #DK3p0d
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ,Lun-aMd
} L}jF#*Q%
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public PaginationSupport findPageByCriteria Tq\~<rEo
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(final DetachedCriteria detachedCriteria, finalint Jg|cvu-+
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startIndex){ it\DZGsg
return findPageByCriteria D_n}p8blT
ZAX0n!db3
(detachedCriteria, PaginationSupport.PAGESIZE, w0j/\XN2s
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startIndex); *fH_lG%
} ./&zO{|0]
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public PaginationSupport findPageByCriteria 'uKkl(==%
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(final DetachedCriteria detachedCriteria, finalint ZG@M%|>
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pageSize, puS&S
*
finalint startIndex){ Q1nDl
return(PaginationSupport) :`Uyn!w
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getHibernateTemplate().execute(new HibernateCallback(){ (\T0n[
publicObject doInHibernate x* =sRf
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(Session session)throws HibernateException { )b&-3$?
Criteria criteria = 5`E`Kb+@
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detachedCriteria.getExecutableCriteria(session); &(1H!
int totalCount = 5K ,#4EOV
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((Integer) criteria.setProjection(Projections.rowCount _}e7L7B7g
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()).uniqueResult()).intValue(); rXY;m-
criteria.setProjection R>d@tr
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(null); )XP#W|;
List items = -.{oqs$
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criteria.setFirstResult(startIndex).setMaxResults ,'C30 A*p
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(pageSize).list(); \6lh `U
PaginationSupport ps = xEVLE,*?>
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new PaginationSupport(items, totalCount, pageSize, 8VP"ydg-U
7}?k^x,1
startIndex); WDEe$k4.
return ps; !.3R~0b
} % Cu.u)/+
}, true); @n7t?9Bx
} L\ }Pzxn
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public List findAllByCriteria(final .73zik
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DetachedCriteria detachedCriteria){ kG)2%
return(List) getHibernateTemplate 6x_T@
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().execute(new HibernateCallback(){ ieo|%N{'
publicObject doInHibernate F&QTL-pQW
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(Session session)throws HibernateException { K DYYB6|
Criteria criteria = {)V? R
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detachedCriteria.getExecutableCriteria(session); !TP6=ks
return criteria.list(); ?wd|G4.Vo
} I?a8h`WS+
}, true); 2wx!Lpr<i_
} P</s)"@
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public int getCountByCriteria(final 60GFVF]'2
{~"7vkc+
DetachedCriteria detachedCriteria){ {r={#mO;p
Integer count = (Integer) E@w[
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getHibernateTemplate().execute(new HibernateCallback(){ O)`fvpVU
publicObject doInHibernate Bx(yu'g|a
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(Session session)throws HibernateException { 5x8'K7/4.
Criteria criteria = Tu]&^[B('
],8;eq%W)
detachedCriteria.getExecutableCriteria(session); `gBD_0<T7
return _QR
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criteria.setProjection(Projections.rowCount Fr-[UZ~V
:GQUM 6
()).uniqueResult(); M
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} k$C"xg2
}, true); Dp*:Q){>E
return count.intValue(); 8q?;2w\l
} >']+OrQH
} C"w,('~@kW
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用户在web层构造查询条件detachedCriteria,和可选的 3bWum
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -#Np7/
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PaginationSupport的实例ps。 jOs
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ps.getItems()得到已分页好的结果集 '/k^C9~m
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ps.getIndexes()得到分页索引的数组 Bg-VCJI<
ps.getTotalCount()得到总结果数 #c-b}.R
ps.getStartIndex()当前分页索引 MDk*j,5V
ps.getNextIndex()下一页索引 +%P t_
ps.getPreviousIndex()上一页索引 Vo%Yf9C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 XdpF&B&K7Q
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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 LZ{YmD&6]
N/K=Ygv.
一下代码重构了。 zLP],wB
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我把原本我的做法也提供出来供大家讨论吧: !Cw!+fZ\l
RcQ>eZHl
首先,为了实现分页查询,我封装了一个Page类:
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java代码: ~;[&K%n
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/*Created on 2005-4-14*/ [[w2p
package org.flyware.util.page; eK'wVg#
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/** wxj>W[V
* @author Joa cf)J )
* t:>x\V2m
*/ y_*n9
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publicclass Page { 8W;2oQN7
Zd[OWF
/** imply if the page has previous page */ nTs/Q V
privateboolean hasPrePage; i2*d+?Er
V$(/0mQV(
/** imply if the page has next page */ c5("-xB
privateboolean hasNextPage; ~b Rd)1
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/** the number of every page */ qIh #~
privateint everyPage; GB>aT-G7q
Gg|M+M?+
/** the total page number */ lyyX<=E{)
privateint totalPage; ^_68]l=
}p=g*Zo*C;
/** the number of current page */ MAnp{
privateint currentPage; %(`#A.yaE
bg}+\/78#
/** the begin index of the records by the current jq(qo4~;
0 " y%9
query */ >Q=Ukn;k
privateint beginIndex; d8E,o7$m
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/** The default constructor */ {^J!<k,R\;
public Page(){ fywvJ$HD]L
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} *_1[[~Aw
@uM EXP
/** construct the page by everyPage L,?/'!xV
* @param everyPage h*3{6X#(/
* */ A2NF<ZsD
public Page(int everyPage){ G`F8!O(
this.everyPage = everyPage; ^,TTwLy-t
} R-
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/** The whole constructor */ WhFS2Jl0
public Page(boolean hasPrePage, boolean hasNextPage, rA1qSG~c
*P!s{i
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int everyPage, int totalPage, |CIC$2u
int currentPage, int beginIndex){ f@@s1gdb
this.hasPrePage = hasPrePage; y\'P3ihK
this.hasNextPage = hasNextPage; \~#WY5
this.everyPage = everyPage; EB!daZH,
this.totalPage = totalPage; (?3[3w~
this.currentPage = currentPage; rCBfD
this.beginIndex = beginIndex; ,PECYwegkt
} lZWK2
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/** ,a0pAj
* @return ;Lo&}U3F,!
* Returns the beginIndex. HI`q1m.
*/ dlD ki.
publicint getBeginIndex(){ ufrqsv]=
return beginIndex; Bu3T/m
} XV>&F{
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/** <x0H@?f7
* @param beginIndex zN~6HZ_:^
* The beginIndex to set. vfw A$7N
*/ r&%.z*q
publicvoid setBeginIndex(int beginIndex){ M T6/2d
this.beginIndex = beginIndex; P`jL]x
} {Dr@HP/x=s
33K*qaRAD
/** +}@8p[`)
* @return J!TBREK
* Returns the currentPage. .A6lj).:
*/ tmJgm5v
publicint getCurrentPage(){ c|AtBgvf
return currentPage; WKl+{e
} TWd;EnNM
g=l:cVr8y
/** XiQkrZ
* @param currentPage QTmZ(>z
* The currentPage to set. ,=BLnsg
*/ .Cz %:%9
publicvoid setCurrentPage(int currentPage){ 2p!"p`b~
this.currentPage = currentPage; ^"i~DC
} wX,F`e3"/
;%Hf)F
/** ?LaUed'
* @return 5$rSEVg9
* Returns the everyPage. h}L}[
*/ fuX'~$b.fA
publicint getEveryPage(){ bZ 443SG
return everyPage; T$+-IAE
} _S@aGw
|Au ]1}
/** hs+kr?Pg`
* @param everyPage T
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* The everyPage to set. {9LWUCpsf
*/ LF*&(NC
publicvoid setEveryPage(int everyPage){ 0;.<~;@h
this.everyPage = everyPage; JkQ\)^5v
} ;V5yXNQ
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/** k2 Q
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* @return v~|?3/{Q
* Returns the hasNextPage. (% _n!ip^
*/ f)Xr!7
publicboolean getHasNextPage(){ <F=9*.@D
return hasNextPage; 1HT_
} 'CR)`G_'[
ve6w<3D@
/** Wu1{[a|
* @param hasNextPage ?rYT4vi
* The hasNextPage to set. b)#Oc,
*/ 5nlMrK
publicvoid setHasNextPage(boolean hasNextPage){ X"aEJ|y
this.hasNextPage = hasNextPage; MXD4|r(
} %^]?5a!
k1
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/** #Q"O4 b:8
* @return w
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* Returns the hasPrePage. %A/_5;PZ/
*/ qk/:A+
publicboolean getHasPrePage(){ %G3(,Qz
return hasPrePage; je/!{(
} O,@~L$a:YZ
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/** _-TA{21)
* @param hasPrePage BB$oq'
* The hasPrePage to set. 3*UR3!Z9
*
*/ SMH<'F7i
publicvoid setHasPrePage(boolean hasPrePage){ y
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this.hasPrePage = hasPrePage; VZ&
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} '(GiF
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/** =3ioQZ^Vz
* @return Returns the totalPage. _5
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* 'B5^P
*/ ?S$i?\Qh
publicint getTotalPage(){ l:#-d.z#
return totalPage; XQ%4L-rhN
} YKmsQ(q`N
Z/;Xl~
/** XW{>-PBg:
* @param totalPage 0& >H^
* The totalPage to set. SP* fv`
*/ v3d&*I
publicvoid setTotalPage(int totalPage){ Y6i _!z[V[
this.totalPage = totalPage; G7!W{;@I
} m%;D
DGW+>\G
} NA3\
osARA3\Xt
tGA :[SP
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hpTDxh'?$C
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 :cu#V
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个PageUtil,负责对Page对象进行构造: m5mu:
java代码:
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/*Created on 2005-4-14*/ 2{-ZD ,(u7
package org.flyware.util.page; I&n
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import org.apache.commons.logging.Log; y Rp"jcD
import org.apache.commons.logging.LogFactory; 98=wnWX6$
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/** KL$bqgc(p3
* @author Joa ^7zu<lX
* 1I@8A>2^OX
*/ N7E$G{TT
publicclass PageUtil { Hbv6_H
kKC9{^%)
privatestaticfinal Log logger = LogFactory.getLog kmzH'wktt
6T 8!xyi-+
(PageUtil.class); DCqY|4Qc
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/** Ookh<ES>
* Use the origin page to create a new page f&v9Q97=
* @param page "ju6XdZo
* @param totalRecords
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* @return ()&~@1U
*/ g&/T*L
publicstatic Page createPage(Page page, int aQ:5d3m0
y.KO :P?5{
totalRecords){ rZ8`sIWQt
return createPage(page.getEveryPage(), *m?/O}R
bfo["
page.getCurrentPage(), totalRecords); lHgs;>U$
} Xpzfm7CB/
cGjPxG;
/** McB[|PmC
* the basic page utils not including exception {G?N E
y;/VB,4V
handler Zd"^</ S
* @param everyPage :
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* @param currentPage N('&jHF
* @param totalRecords n:MdYA5,m
* @return page 2eMTxwt*S
*/ J!5$,%v
publicstatic Page createPage(int everyPage, int J:V?EE,\-
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currentPage, int totalRecords){ B)d(TP,>
everyPage = getEveryPage(everyPage); pz"0J_xDM
currentPage = getCurrentPage(currentPage); ,VO2a mI
int beginIndex = getBeginIndex(everyPage, pK0"%eA
*6q5S4 r
currentPage); E>l~-PaZY
int totalPage = getTotalPage(everyPage, 9B;{]c
lg^Z*&(
totalRecords); 7uzkp&+:
boolean hasNextPage = hasNextPage(currentPage, 9a8cRt6knO
wI(M^8F_Mf
totalPage); k:7(D_
boolean hasPrePage = hasPrePage(currentPage); ;!yQ
Gz.|]:1
returnnew Page(hasPrePage, hasNextPage, H%D$(W
everyPage, totalPage, GSH>7!.#
currentPage, SL5Ai/X0N
!qG7V:6
beginIndex); {.XEL
} $< JaLS
.mR8q+I6
privatestaticint getEveryPage(int everyPage){ <7~'; K
return everyPage == 0 ? 10 : everyPage; q<M2,YrbAI
} jyCXJa-!-
q@{Bt{$x
privatestaticint getCurrentPage(int currentPage){ GWfL
return currentPage == 0 ? 1 : currentPage; $&=S#_HQS
} JD|=>)
u A<n
privatestaticint getBeginIndex(int everyPage, int ez|)ph7
]9^sa-8
currentPage){ 1jcouD5?H
return(currentPage - 1) * everyPage; }~L.qG
} E 7{U|\
H*}y^)x
privatestaticint getTotalPage(int everyPage, int ~A\GT$
> ;*b|Ik
totalRecords){ uLV#SQ=bZN
int totalPage = 0; {e 14[0U-
nlc
"c5;jh
if(totalRecords % everyPage == 0) p>huRp^w
totalPage = totalRecords / everyPage; $&n=$C&x
else F1yqxWHeo
totalPage = totalRecords / everyPage + 1 ; [1S|dc>.O%
" )1V]}+m
return totalPage; cz8T
} p^w;kN
lNYt`xp
privatestaticboolean hasPrePage(int currentPage){ JJN.ugT}1
return currentPage == 1 ? false : true; 9P+-#B
} vQ
6^xvk]
ZpQ)IHA.
privatestaticboolean hasNextPage(int currentPage, cPlZXf
]Gsv0Xk1
int totalPage){ s*. hl.k.
return currentPage == totalPage || totalPage == T{-CkHf9Q
5j?3a1l0
0 ? false : true; yd
d7I&$
} \XZ/v*d0
ds<2I,t
``hf=`We
} ~x1$h#Cx'
Q ~#Wf?
.(cw>7e3D
R\!2l|_
I=`U7Bis"
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Fj2BnM3#
,?^ p(w
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ,s"^kFl
#V~me
做法如下: a.k.n<
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0Qf,@^zL*
},{$*f[
的信息,和一个结果集List: rX2.i7i,
java代码: QTk}h_<u
!$gR{XH$]
GjvOM y
/*Created on 2005-6-13*/ N5lDS
package com.adt.bo; Pd_U7&w,5
8}O lL,fP
import java.util.List; at,XB.}Z]
4O^xY
6m
import org.flyware.util.page.Page; SE1=>S%p
'-Vt|O_Q
/** I 5^!y
* @author Joa I;wp':
*/ t.i 8
2Q
publicclass Result { -cAo@}v
_@
qjV~%Sy
private Page page; 286jI7 T
pmyXLT
private List content; 2K/4Rf0;
L
[pBB
/** 4V)kx[j
* The default constructor #lL^?|M
*/ .SU8)T
public Result(){ ,is3&9
super(); rZ}:Z'`
} TrEu'yxy8*
kTOzSiq
/** ( R=:X+ k
* The constructor using fields f<d`B]$(
* s<<ooycBrQ
* @param page ];[}:f
* @param content dO!
kk"qn
*/ ^BikV
public Result(Page page, List content){ *av<E
this.page = page; E Nhl&J
this.content = content; Q{>+ft U
} <lPm1/8
\wz6~5R
/** l<58A7
* @return Returns the content. he;dq)-e9
*/ +V ;l6D
publicList getContent(){ 61C7.EZZ;
return content; Bu~]ey1
} 3Ei#q+7
Fo5FNNiID
/** X9W@&zQ
* @return Returns the page. ]8_NZHld
*/ 5H<m$K4z
public Page getPage(){ KOk4^#h@
return page; ;u_X)
} ?jv/TBZX4
-A^ _{4X
/** +SR+gE\s0
* @param content P^~yzI
* The content to set. _7Ju
*/ ] vHF~|/-
public void setContent(List content){ >
PRFWO
this.content = content; JE "x
} q$d>(vbq
AUG#_HE]k
/** c<:-T
* @param page t6"%3#s
* The page to set. X:"i4i[}{9
*/ Cn34b_Sbd
publicvoid setPage(Page page){ |.: q
this.page = page; RB7tmJc
} ^,TO#%$iE
} MS~(D.@ZS
!Iy_UfW
V(I8=rVH
$Vg>I>i
BO?%'\
2. 编写业务逻辑接口,并实现它(UserManager, zZPO&akB"
nV|EQs4(
UserManagerImpl) mp1@|*Sn
java代码: Uiw2oi&_
3wF;GG
nfbR
P t
/*Created on 2005-7-15*/ GY'%+\*tj
package com.adt.service; #jvtUS \
hR?{3d#x2
import net.sf.hibernate.HibernateException; `,<BCu
hn
GZ=
import org.flyware.util.page.Page; PJ|P1O36a
Ua: sye
import com.adt.bo.Result; gD@){Ip
JYI,N
/** e8a+2.!&\
* @author Joa sUO`u qZV
*/ z\W64^'"Z
publicinterface UserManager { ,]F,Uu_H7
A:%`wX}
public Result listUser(Page page)throws YoNDf39
Jq-]7N%k/
HibernateException; \;Biq`
y'q$|
} AO4U}?
1v27;Q<+Q
b4 6~?*
`Y$4 H,8L
*~e?TfG
java代码: eF$x 1|
JG rWHIsNV
%$Tji
/*Created on 2005-7-15*/ m=:9+z
package com.adt.service.impl; x=P\qjSa
Dw.J2>uj
import java.util.List; m+[Ux{$
c7k~S-nU
import net.sf.hibernate.HibernateException; H/
HMm{4
C ;W"wBz9
import org.flyware.util.page.Page; lTgjq:mn
import org.flyware.util.page.PageUtil; rglXs
~q.F<6O
import com.adt.bo.Result; p8O2Z?\
import com.adt.dao.UserDAO; $7ZX]%<s
import com.adt.exception.ObjectNotFoundException; x|Bf-kc[#Q
import com.adt.service.UserManager; +~$ ]}%
!wVM= z^G
/** <iC(`J$D
* @author Joa j</: WRA`]
*/ Wqw1J=]
publicclass UserManagerImpl implements UserManager { *i%.;Z"
%5n_
p^xp
private UserDAO userDAO; X&`t{Id?6
E{`fF8]K
/** 45c$nuZ
* @param userDAO The userDAO to set. *])
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*/ /W<;Z;zk
publicvoid setUserDAO(UserDAO userDAO){ jV1.Yz(`
this.userDAO = userDAO; EV%gF
} R&k<AZ
Ow,w$0(D
/* (non-Javadoc) FTUv IbT
* @see com.adt.service.UserManager#listUser |/{=ww8|
VlsnL8DV
(org.flyware.util.page.Page) f.$af4
u
*/ .M%}X7
public Result listUser(Page page)throws qo bc<-
*.t7G
HibernateException, ObjectNotFoundException { .W!i7
int totalRecords = userDAO.getUserCount(); fIU#M]Xx
if(totalRecords == 0) }S-O&Z
throw new ObjectNotFoundException VU3upy<
`Ggbi4),
("userNotExist"); JK5gQ3C[
page = PageUtil.createPage(page, totalRecords);
ZBp/sm
List users = userDAO.getUserByPage(page); bWU'cw
returnnew Result(page, users); H<,gU`&R
} $'M!HJxb
iqWQ!r^
} on`3&0,.
<>rneHl8
m;QMQeGz
hz@bW2S.
rg!r[1c
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rjYJs*#
Qp3_f8
询,接下来编写UserDAO的代码: OQJ6e:BGt
3. UserDAO 和 UserDAOImpl: q@8*Xa >
java代码: W/h[A3 `3N
}K|oicpUg
H* *Xu;/5@
/*Created on 2005-7-15*/ s.C_Zf~3
package com.adt.dao; &V/MmmT
*z8\Lnv~k
import java.util.List; k5pN
%*}(}~
import org.flyware.util.page.Page; 2\{zmc}G-0
uKHxe~
import net.sf.hibernate.HibernateException; M8(t'jN
4H&+dRI"
/** eng'X-x
* @author Joa "^%cJAnLX
*/ jNk%OrP]
publicinterface UserDAO extends BaseDAO { L4nYXW0y
VMWf>ZU
publicList getUserByName(String name)throws pW3^X=6
6j}9V
L77
HibernateException; 4,DeHJjAlE
t b}V5VH
publicint getUserCount()throws HibernateException;
}.6[qk
( a#BV}=
publicList getUserByPage(Page page)throws pv|G^,>#
<RL]
HibernateException; P&LsVR{#
FQ\h4` >B
} /%^#8<=|U
4Fr
N~'c_l
>z@0.pN]7
c\j/k[\<
java代码: PEZ!n.'S
=UWI9M*sz
|yPu!pfl
/*Created on 2005-7-15*/ I; rGD^
package com.adt.dao.impl; Cp0=k
WH^%:4
import java.util.List; nU7[c| =
5nx1i
import org.flyware.util.page.Page; w``U=sfmV
>^3i|PB
import net.sf.hibernate.HibernateException; Qo|\-y-#
import net.sf.hibernate.Query; tKXIk9e
SE*g;Cvg1
import com.adt.dao.UserDAO; j0q&&9/Jj
4j^
@wV'
/** 3u0RKLc\
* @author Joa r9?Mw06Wc5
*/ U 6)#}
public class UserDAOImpl extends BaseDAOHibernateImpl h/Y'<:
LrpM\}t
implements UserDAO { }Zp,+U*"
|2A:eI8 ^
/* (non-Javadoc) dk^~;m#iN
* @see com.adt.dao.UserDAO#getUserByName K{+2G&i
'LDQgC*%
(java.lang.String) fp"W[S|uL
*/ 4 #Jg9o
publicList getUserByName(String name)throws O;3>sLgc
p5*EA
x
HibernateException { =7UsVn#o
String querySentence = "FROM user in class cFX p
xskz)kk
com.adt.po.User WHERE user.name=:name"; 3Jn;}
Query query = getSession().createQuery ]6j{@z?{
v`T
c}c '
(querySentence); qf-8<{T
query.setParameter("name", name); )boE/4
return query.list(); M<&= S
} ;$Jo+#
{P-):
/* (non-Javadoc) 1|=A*T-<M
* @see com.adt.dao.UserDAO#getUserCount() |Y.?_lC
*/ :Zlwy-[
publicint getUserCount()throws HibernateException { 0=$T\(0g
int count = 0; 'Pbr
v
String querySentence = "SELECT count(*) FROM :Hbv)tS\3w
uXiN~j &Be
user in class com.adt.po.User"; #O&8A
Query query = getSession().createQuery Pg{J{gn
m]&SN z=
(querySentence); t6t!t*jO
count = ((Integer)query.iterate().next |N] XJ)?
K(|}dl:
()).intValue(); \OoWo
return count; 7t3!)a|lI
} ~}Pfu
Vjpy~iP4B
/* (non-Javadoc) |uJ%5y#
* @see com.adt.dao.UserDAO#getUserByPage G#$-1"!`
J .<F"r>
(org.flyware.util.page.Page) |V(0GB
*/ yt2PU_),
publicList getUserByPage(Page page)throws 6L~n.5B~o
4^d?D!j
HibernateException { 0*v2y*2V
String querySentence = "FROM user in class XK vi=0B
cz$2R
com.adt.po.User"; ,#K'PB4 E
Query query = getSession().createQuery [D1Up
19] E 5'AI
(querySentence); !<h)w#>en
query.setFirstResult(page.getBeginIndex()) xyxy`qR A
.setMaxResults(page.getEveryPage()); @(lh%@hO
return query.list(); l+b~KU7~l
} |vC~HJpuv'
{.]7!ISl5
} 2KZneS`
;F Eqe49
[fyLV`
K)P%;X
!@"OB~
至此,一个完整的分页程序完成。前台的只需要调用 rZpXPI
3(UVg!t
userManager.listUser(page)即可得到一个Page对象和结果集对象 %}T6]S)%u
H;"4C8K7
的综合体,而传入的参数page对象则可以由前台传入,如果用 !`r$"}g
)M^
gT}M
webwork,甚至可以直接在配置文件中指定。 ]_$[8#kg
p]"4#q\(
下面给出一个webwork调用示例: &e3.:[~_?
java代码: 4&iCht
=
vKR[&K{Z|
y_[vr:s5pG
/*Created on 2005-6-17*/ tl>7^hH
package com.adt.action.user; 7-A2_!_x{
E(|>Ddv B&
import java.util.List; 8cQ'dL`(
yh=N@Z*zP
import org.apache.commons.logging.Log; Bbp|!+KP{(
import org.apache.commons.logging.LogFactory; q cno^8R
import org.flyware.util.page.Page; LH6vLuf
}PpUAt~g
import com.adt.bo.Result; _
x*3PE
import com.adt.service.UserService; >R=|Wo`Ri
import com.opensymphony.xwork.Action; Mb=" Te>|
fXB0j;A
/** Vw"\{`
* @author Joa tf G@&&%9
*/ fc@A0Hf
publicclass ListUser implementsAction{ 13wE"-
048kPXm`
privatestaticfinal Log logger = LogFactory.getLog XX~,>Q}H=
wyG;8I
(ListUser.class); :Tq~8!s
[/ZO q
private UserService userService; :hA#m[
~)'k 9?0
private Page page; rM"l@3hP
+/\6=).\
privateList users; BerwI
7!=
K|@G t%Y
/* 2Rz
* (non-Javadoc) QS j]ZA
* L%5%T;0'~
* @see com.opensymphony.xwork.Action#execute() \j.:3Xr
*/ @ .KGfNu
publicString execute()throwsException{ FPTK`Gd0
Result result = userService.listUser(page); h7@6T+#WoT
page = result.getPage(); g
`4<9RMun
users = result.getContent(); mVmGg,
return SUCCESS; jFb?b6b
} mBC+6(5V
YbLW/E\T
/** L=h'Qgk%
* @return Returns the page. .sA.C]f
*/ 'ig'cRD6N
public Page getPage(){ hzC>~Ub5
return page; r_.S>]
} *$*ce|V5
Vz[C=_m
/** 4/)k)gLI
* @return Returns the users. F<w/PMb
*/ RT5T1K08I
publicList getUsers(){ MY/}-*|
return users; LIdF 0
} ::F|8
Np)lIGE
/** :i7;w%B
* @param page =qIyqbXz
* The page to set. )_NO4`ejs/
*/ Q7A MRrN
publicvoid setPage(Page page){ Vq2$'lY
this.page = page; ;=UsAB]
} WjjB<YKzF
{_dvx*M
/** %K
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* @param users d5l UGRg
* The users to set. 4`R(?
*/ RrgGEx
publicvoid setUsers(List users){ .[ mRM
this.users = users; *9i{,I@
} |WUG}G")*x
s9d_GhT%-
/** 4Xv*wB1
* @param userService uwBiW
* The userService to set. IIqUZJ
*/ &"q=5e2
publicvoid setUserService(UserService userService){ Q5_o/wk
this.userService = userService; lNBL4yM
} M#[{>6>iE
} 6`-jPR
JMM W
[fIg{Q
7[wieYj{
3[f):
u3"
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, ,v&(Y Od
8JD,u
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 <Ok3FE.K
O| hpXkV
么只需要: +'w3 =2Bo
java代码: r"R#@V\'1b
cFWc<55aX6
zv"Z DRW
<?xml version="1.0"?> x$%!U[!3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork I`p;F!s
as_PoCoss
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C6yuX\
eR" <33{
1.0.dtd"> ;({W#Wa
NgCvVWto
<xwork> @ry_nKr9
]g&TKm
<package name="user" extends="webwork- y^%y<~f
IaXeRq?<
interceptors"> .6'qoo_N
tnG# IU
*
<!-- The default interceptor stack name alvrh'51
6K<K
--> Tu 7QCr5*
<default-interceptor-ref r>U@3%0&
JO<wU
name="myDefaultWebStack"/> "w.3Q96r
3%ZOKb"D*
<action name="listUser" n.G!43@*N
DDH:)=;z
class="com.adt.action.user.ListUser"> XvlU*TO~(~
<param 8ITdSg
#YOA`m,'
name="page.everyPage">10</param> E\,-XH
<result 1y4
^`>/.gL
name="success">/user/user_list.jsp</result> $p?aVO
</action> {!dVDf_
E+w<RNBmz
</package> `^y7f
n=ux5M
</xwork>
(ICd}
}U9G
u-5{U-^_
d{7+w/Zi
tC9n
k5~
Oo%d]8W
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 3kMf!VL
FG*r'tC~r
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 7x4PaX(
qm o9G
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 sp*v?5lW
#?9;uy<j.q
*ppffz
xX4N4vb
"!%l/_p?
我写的一个用于分页的类,用了泛型了,hoho 6b \&~b@T
`lt"[K<
java代码: =>af@C.2
A=wh@"2
v OpKNp
package com.intokr.util; -pXSSa;O9
%Q dn
import java.util.List; kq,ucU%>p
e&aWq@D
/** r?
E)obE
* 用于分页的类<br> }@+:\
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~1vDV>dpE
*
O+Y6N
* @version 0.01 xx%j.zDI]
* @author cheng c|@bwat4
*/ lv+TD!b
public class Paginator<E> { psMvq@>
privateint count = 0; // 总记录数 *6DB0X_-}
privateint p = 1; // 页编号 g~A`N=r;h
privateint num = 20; // 每页的记录数 -:y,N
9^
privateList<E> results = null; // 结果 P! #[mio
.+A+|yR
/** 1F&Trqq
* 结果总数 [}0haTYc4
*/ Q| ?L*Pq2I
publicint getCount(){ 76h ,]xi
return count; =mp;.k95
} zsyIV!(
#KexvP&*
publicvoid setCount(int count){ orMwAV
this.count = count; aH/
k Ua
}
k5.Lna
'op|B@y
/** <s<n
* 本结果所在的页码,从1开始 KEjWRwN
* O5nD+qTQ#
* @return Returns the pageNo. .MoU1n{Yc
*/ RO/FF<f
publicint getP(){ ~;{;,8!)
return p; G^4hd i3@
} iN8zo:&Z
M {T-iW"
/** 4-H+vNG{%
* if(p<=0) p=1 * kDC liL
* IE/^\ M
* @param p ieCEo|b
*/ iE^84l68
publicvoid setP(int p){ G.a b ql
if(p <= 0) h-<81"}j1
p = 1; dufu|BL|}
this.p = p; Ata:^qI
} :hk5 .[
Y;^l%ePuW
/** d K3*;
* 每页记录数量 %^GfS@t
*/ ARwD~Tr
publicint getNum(){ SdxDa
return num; hxd`OG<gF
} 'Nnz k
peuZ&yK+"
/** V/
uP%'cd
* if(num<1) num=1 '3DXPR^B6
*/ ca*DZG/
publicvoid setNum(int num){ ']z{{UNUN
if(num < 1) YdC6k?tzS
num = 1; rkCx{pe9
this.num = num; 4`]^@"{
} ]i ,{
FX`>J6l:X
/** KD7dye
* 获得总页数 Tg)|or/%
*/ O6a<`]F
publicint getPageNum(){
zC@o
return(count - 1) / num + 1; j<jN05p
} })8N5C+KU
`WFw3TI
/** a PfO$b:
* 获得本页的开始编号,为 (p-1)*num+1 J1RJ*mo7,
*/ GmEJhr.3`=
publicint getStart(){ cyv`B3}
return(p - 1) * num + 1; Z=Y& B>:[
} JZ*/,|1}EC
sRL`dEl4l
/** >xYpNtEs
* @return Returns the results. 9gEwh<
*/ C>j@,G4
publicList<E> getResults(){ ]kRfB:4ED
return results; _] sn0rX
} 1AfnzGvA
}mq6]ZrK
public void setResults(List<E> results){ dIa+K?INX
this.results = results; xU>WEm2
} RD'Q :W
#crQ1p) \
public String toString(){ #9}D4i.`}
StringBuilder buff = new StringBuilder D] jzAx
lVR~Bh
(); T?soJ]A
buff.append("{"); ?2;&O`x*
buff.append("count:").append(count); ag#S6E^%S
buff.append(",p:").append(p); z.9U}F
buff.append(",nump:").append(num); %x{kc3PnO
buff.append(",results:").append m=A(NKZ
[OV"}<V
(results); mPN@{.(j
buff.append("}"); aa?b`[Xa
return buff.toString(); H*&f: