Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 7.`:Z_
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y(0";\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 '"14(BvW
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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 b)Dzau
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分页支持类: \1b! I)T9
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java代码: .l(t\BfE~
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package com.javaeye.common.util; Ju.B!)uS#
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import java.util.List; COk;z.Kn
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publicclass PaginationSupport { Foc) u~
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publicfinalstaticint PAGESIZE = 30; /K<.$B8
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privateint pageSize = PAGESIZE; LU4k/
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privateList items; +Pm
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privateint totalCount; ?Wz
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privateint[] indexes = newint[0]; O4i5fVy{
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privateint startIndex = 0; N]6M4j!
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public PaginationSupport(List items, int W4~:3Sk
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totalCount){ `$odxo+
setPageSize(PAGESIZE); b 5X~^L
setTotalCount(totalCount); :RE.m d
setItems(items); _mJnhT3
setStartIndex(0); DHlCus=ic
} i-`n5,
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public PaginationSupport(List items, int |p"E0av
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totalCount, int startIndex){ WfDpeXdO
setPageSize(PAGESIZE); {Ex*8sU%p%
setTotalCount(totalCount); kt*""&R
setItems(items); LCMCpEtY*K
setStartIndex(startIndex); 3A(sT}
} }+1Y>W7q
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public PaginationSupport(List items, int
{Bb:S"7NX
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totalCount, int pageSize, int startIndex){ SsE8;IGH
setPageSize(pageSize); "Wz#<! .r
setTotalCount(totalCount); . w_oW mD
setItems(items); F qW[L>M'
setStartIndex(startIndex); R|Lr@k{6+r
} 05cyWg9a
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publicList getItems(){ L| uoFG{
return items; ~:\QC
} #gL$~.1
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publicvoid setItems(List items){ W%xg;uzp
this.items = items; MWxv\o
} N5%zbfKM
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publicint getPageSize(){ ~;*SW[4
return pageSize; SXW8p>1Jw
} ,c;u]
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publicvoid setPageSize(int pageSize){ oS/cS)N20
this.pageSize = pageSize; [o0Z;}fU
} K9YD)351t
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publicint getTotalCount(){ }
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return totalCount; 8 N5ga
} Q8kdX6NMd&
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publicvoid setTotalCount(int totalCount){ Wp[R$/uT
if(totalCount > 0){ &Q85B q
this.totalCount = totalCount; eKq`t.*Ft
int count = totalCount / qx $-% P
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pageSize; K38A;=t9
if(totalCount % pageSize > 0) ?x|8"*N
count++; EN =oA P
indexes = newint[count]; 0=2D90
for(int i = 0; i < count; i++){ v ;q<h
indexes = pageSize * 8Q%rBl.
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i; ;;9W/m~]
} xsPE UK&g
}else{ oP$l( k
this.totalCount = 0; J4Ix\r_
} $cxulcay=
} eco i4f
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publicint[] getIndexes(){ MMZdF{5@G
return indexes; sMq*X^z
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} rl0sN5n
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publicvoid setIndexes(int[] indexes){ i9qn_/<c
this.indexes = indexes; BixKK$Lo
} &3SQVOW ~T
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publicint getStartIndex(){ {PXN$p:'
return startIndex; GtC bzNY
} l 4zl|6%
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publicvoid setStartIndex(int startIndex){ yj6o533o
if(totalCount <= 0) 0<8pG:BQ
this.startIndex = 0; +$hqwNh@Z@
elseif(startIndex >= totalCount) y7;i4::A\
this.startIndex = indexes bF#* cH
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[indexes.length - 1]; meHnT9a^
elseif(startIndex < 0) XF`,mV4
this.startIndex = 0; oQ!56\R
else{ *vL2n>HH
this.startIndex = indexes &vf%E@<
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[startIndex / pageSize]; v[r5!,F
} 1 h.=c
} )}-,4Iu%
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publicint getNextIndex(){ Hqel1J
int nextIndex = getStartIndex() + ;^q@w
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pageSize; 7gL N7_2
if(nextIndex >= totalCount) eVobs2s
return getStartIndex(); 1e 8J-Nkj
else T+O Qa+E@P
return nextIndex; Vt {uG
} 'w?*4H
k* ayzg3F>
publicint getPreviousIndex(){ 7fVlA "x
int previousIndex = getStartIndex() - hP=^JH
_&Hq`KJm
pageSize; E^:8Jehq
if(previousIndex < 0) 7r`A6 \
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return0; K8sgeX|
else na;U]IK
return previousIndex; v&hQ;v
} Q-3o k7
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} U#I8Rd I,
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抽象业务类 J33enQd
java代码: 3;wAm/Z:Q
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/** d-=RS]j;j
* Created on 2005-7-12 wj-=#gyAoo
*/ }9&Z#1/
package com.javaeye.common.business; @a08*"lbp
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import java.io.Serializable; wA+QUN3#n
import java.util.List; (]JZ1s|
or?@Ti;
import org.hibernate.Criteria; PSOW}Y|q
import org.hibernate.HibernateException; qSB]Zm<
import org.hibernate.Session; w4m-DR5
import org.hibernate.criterion.DetachedCriteria; 3{gD'y4j
import org.hibernate.criterion.Projections; *SW.K{{
import E8[{U8)[;5
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org.springframework.orm.hibernate3.HibernateCallback; i+x$Y)=
import F/MzrK\':m
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org.springframework.orm.hibernate3.support.HibernateDaoS f`zH#{u
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upport; ,/d
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import com.javaeye.common.util.PaginationSupport; W'3&\}
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public abstract class AbstractManager extends [(Z sQK
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HibernateDaoSupport { f}jo18z%
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privateboolean cacheQueries = false; s:_M+_7_
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privateString queryCacheRegion; n|t?MoUP
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publicvoid setCacheQueries(boolean vx:MLmZ.
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cacheQueries){ tY?_#rc
this.cacheQueries = cacheQueries; q|*}>=NX
} 'S_kD! BO
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publicvoid setQueryCacheRegion(String ^tWt"GgC
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queryCacheRegion){ K+3dwQo
this.queryCacheRegion = >C6wm^bl
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queryCacheRegion; $D`~X`
} (&n4^tJ+_
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publicvoid save(finalObject entity){ -JL
getHibernateTemplate().save(entity); m7zx,bz>
} ooJ ^8L
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publicvoid persist(finalObject entity){ tc go
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getHibernateTemplate().save(entity); $U,`M"
} 8vzjPWu
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publicvoid update(finalObject entity){ 3|$>2IRq
getHibernateTemplate().update(entity); 1!u}~E_
} ',?9\xEB
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publicvoid delete(finalObject entity){ e-$U .cx
getHibernateTemplate().delete(entity); %+PWcCmn
} J.
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publicObject load(finalClass entity, 9fk@C /$
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finalSerializable id){ 'qGKS:8
return getHibernateTemplate().load Y2&>;ym!
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(entity, id); h/h`?vWu
} DP2 ^(d<
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publicObject get(finalClass entity, it=4cHT
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finalSerializable id){ aq~g54
return getHibernateTemplate().get )` nX~_'p
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(entity, id); QPe+K61U
} ]B;GU
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publicList findAll(finalClass entity){
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return getHibernateTemplate().find("from ENlqoj1
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" + entity.getName()); */=5m]
} a );>
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publicList findByNamedQuery(finalString .C
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namedQuery){ #;Yn8'a~
return getHibernateTemplate u{0'"jVJ
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().findByNamedQuery(namedQuery); N3P!<J/tc
} [4)q6N5`f
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publicList findByNamedQuery(finalString query, ->DfT*)
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finalObject parameter){ Vp =
return getHibernateTemplate Fs^d-I
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().findByNamedQuery(query, parameter); cswX?MN
} ?Ji.bnfK
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publicList findByNamedQuery(finalString query, ~z)diF<
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finalObject[] parameters){ R|PFGhi6"A
return getHibernateTemplate p5<2t SD
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().findByNamedQuery(query, parameters); F...>%N$
} (mq 7{;7y
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publicList find(finalString query){ "0pH@_8o{
return getHibernateTemplate().find B_FfXFQm<
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(query); z7+y{-{Z
} ([loWr}QR
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publicList find(finalString query, finalObject 0 S3~IeJ
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parameter){ \>0F{-cR$
return getHibernateTemplate().find pg3B^
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(query, parameter); lk $S"OH!
} A1xY8?#?~c
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public PaginationSupport findPageByCriteria ygm4A j>
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(final DetachedCriteria detachedCriteria){ 0{ovLzW
return findPageByCriteria *uYnu|UQH
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Jhbkp?Zli
} OtuOT=%
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public PaginationSupport findPageByCriteria <UJgl{-
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(final DetachedCriteria detachedCriteria, finalint u@SE)qg
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startIndex){ Q1qf'u
return findPageByCriteria owA3>E5t&
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(detachedCriteria, PaginationSupport.PAGESIZE, fo])=KM
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startIndex); {;4AdZk
} &&e{ 9{R
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public PaginationSupport findPageByCriteria 9wLV\>i[k
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(final DetachedCriteria detachedCriteria, finalint 7)zn[4v7qt
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pageSize, l 6wX18~XJ
finalint startIndex){ \LB =_W$
return(PaginationSupport) nVI\Or[
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getHibernateTemplate().execute(new HibernateCallback(){ }a@ZFk_>
publicObject doInHibernate [ V`j@dV
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(Session session)throws HibernateException { X<s']C9c
Criteria criteria = R4,j
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detachedCriteria.getExecutableCriteria(session); YIA}F1:
int totalCount = }S6Sz&)
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((Integer) criteria.setProjection(Projections.rowCount +r)'?zU
11}fPWK
()).uniqueResult()).intValue(); .?b2Bd!MC
criteria.setProjection .fxI)
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(null); -ecP@,
List items = 0;'kv|
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criteria.setFirstResult(startIndex).setMaxResults *a Y`[,4#$
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(pageSize).list(); #3maT*JY
PaginationSupport ps = 'j=7'aX>K
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new PaginationSupport(items, totalCount, pageSize, E)|_7x<u
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startIndex); .E|Hk,c9
return ps; l)E
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} bL5z%bV
}, true); xKKL4ws
} D3yG@lIP3
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public List findAllByCriteria(final *zX*k7LnV
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DetachedCriteria detachedCriteria){ e!yUA!x`u
return(List) getHibernateTemplate v=?U{{xQ
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().execute(new HibernateCallback(){ #5O'XH5_
publicObject doInHibernate V%&t'H{
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(Session session)throws HibernateException { Xg.'<.!g0
Criteria criteria = /E(H`;DG
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detachedCriteria.getExecutableCriteria(session); xd8UdQ,lt
return criteria.list(); -bo2"*|m
} W;*rSK|(Sc
}, true); `pY\Mmgv1
} ^a|$z$spf
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public int getCountByCriteria(final $enh>!mU
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DetachedCriteria detachedCriteria){ vBsd.2t~
Integer count = (Integer) >x)YdgJ*
}(O/ y-
getHibernateTemplate().execute(new HibernateCallback(){ !_s|h@
publicObject doInHibernate hNUAwTH6
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(Session session)throws HibernateException { iC&=-$vu
Criteria criteria = HTI1eLZ2
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detachedCriteria.getExecutableCriteria(session); 1&c>v3 $2
return 8Q^yh6z
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criteria.setProjection(Projections.rowCount CFqoD l
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()).uniqueResult(); :7p0JGd
} TCp!4-~,
}, true); a&)0_i:r
return count.intValue(); Pgg6(O9}B^
} c"t1E-Nsk
} BQ[1,\>
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用户在web层构造查询条件detachedCriteria,和可选的 nL@
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 FCQoz"M
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PaginationSupport的实例ps。 6BVV2j)zl:
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ps.getItems()得到已分页好的结果集 )7=B]{B_
ps.getIndexes()得到分页索引的数组 P]T(I/\g
ps.getTotalCount()得到总结果数 X`]-)(UX
ps.getStartIndex()当前分页索引 G;V@oT
ps.getNextIndex()下一页索引 /dhx +K~
ps.getPreviousIndex()上一页索引 Pca~V>Hd
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 jpyV52
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 KSVIX!EsX
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一下代码重构了。 5. :To2
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我把原本我的做法也提供出来供大家讨论吧: 0~A<AF*t
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首先,为了实现分页查询,我封装了一个Page类: Nv*x^y]
java代码: >OE.6)'Rm
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/*Created on 2005-4-14*/ %H>vMR-,~
package org.flyware.util.page; l7aGo1TcIh
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/** *x`z5_yfO
* @author Joa FFbMG:>:
* <.$<d
*/ dJ?VN!B0
publicclass Page { Q'JE DH\
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/** imply if the page has previous page */ qh0)~JL4
privateboolean hasPrePage; &o^ wgmS
/`\-.S9
/** imply if the page has next page */ BArsj
privateboolean hasNextPage; nen6!bw4
E{T\51V]%
/** the number of every page */ GWjKZ1p
privateint everyPage; Jkpw8E7
@<CJbFgJp
/** the total page number */ @5
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privateint totalPage; 9/}i6j8Z
s7I*=}{g0.
/** the number of current page */ ,p1 (0i
privateint currentPage; =/6.4;8
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/** the begin index of the records by the current E2(;R!ML#
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query */ ="@W)"r
privateint beginIndex; 1?(BWX)7
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/** The default constructor */ sl6p/\_w
public Page(){ {,IWjt &>
?MKf=!w
} P)1@HDN==
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/** construct the page by everyPage `"AjbCL
* @param everyPage }S*6+4
* */ "1%<IqpU+
public Page(int everyPage){ "x\3`Qk
this.everyPage = everyPage; _QvyFKAM
} C>v
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Ds
/** The whole constructor */ (N;Jw^C@
public Page(boolean hasPrePage, boolean hasNextPage, (&x~pv"+
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vR,HCI
int everyPage, int totalPage, pC8(>gV<h
int currentPage, int beginIndex){ enG6T
this.hasPrePage = hasPrePage; YL){o$-N"J
this.hasNextPage = hasNextPage; G8u8&|
this.everyPage = everyPage; ^l$(- #'y
this.totalPage = totalPage; YD.3FTNGC
this.currentPage = currentPage; |\QR9>
this.beginIndex = beginIndex; O b8[P=
} 3;>(W
wB9IP{Pf
/** L%B+V;<h3
* @return =v:_N.Fh-c
* Returns the beginIndex. 07(E/A]
*/ ++&F5'?g
publicint getBeginIndex(){ $)n{}8^
return beginIndex; Maa5a
} ~;+i[Z&e
.Z_U]_(
/** (R6ZoBZ
* @param beginIndex S<Q1
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* The beginIndex to set. <(f4#BP
*/ K"}Dbr
publicvoid setBeginIndex(int beginIndex){ \W=
this.beginIndex = beginIndex; cYbO)?mC_
} +D
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/** {_q2kk
* @return 46XB6z01
* Returns the currentPage. rA1
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*/ 8OBvC\%
publicint getCurrentPage(){ 2$\f !6p
return currentPage; s|,]Nb=z/
} ZM|>Va/X
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/** RLKO0 #
* @param currentPage J&3;6I
&
* The currentPage to set. 3_h%g$04s
*/ z?
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publicvoid setCurrentPage(int currentPage){ z9D2,N.
this.currentPage = currentPage; (XW#,=rYk
} spl*[ d
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/** |HG%o
3E]
* @return %1=W#jz
* Returns the everyPage. 2X*epU_1h
*/ xDQ$Ui.
publicint getEveryPage(){ 2f:'~ P56
return everyPage; ItRGq
} 'R'>`?Nh
w}YHCh
/** )j9FB
* @param everyPage ]$L[3qA.
* The everyPage to set. +\W"n_PPy
*/ >^ Y9p~
publicvoid setEveryPage(int everyPage){ PN'8"8`{
this.everyPage = everyPage; NGze: gPmO
} "q(&<+D@
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/** 4;*V^\',9
* @return mD=?C
* Returns the hasNextPage. t&&OhHK
*/ *,Re&N8
publicboolean getHasNextPage(){ %]R#}amW
return hasNextPage; `Ch6"=t
} P\M+ZA ;
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/** ALwuw^+
* @param hasNextPage Olno9_'
* The hasNextPage to set. kl={L{r
*/ 5sE^MS1
publicvoid setHasNextPage(boolean hasNextPage){ {c J6Lq&
this.hasNextPage = hasNextPage; y&CUT:M6
} .U1dcL6
Y{O&-5H^|
/** ex|kD*=
* @return gSGe]
* Returns the hasPrePage. A]J^{h0k
*/ hD,-!R
publicboolean getHasPrePage(){ AzV5Re8M
return hasPrePage; wH`@r?&
} n;=A'g|Q
c !;wp,c
/** x:bYd\
EJ[
* @param hasPrePage <VBw1|)$@
* The hasPrePage to set. : 1{j&$
*/ "/"qg
publicvoid setHasPrePage(boolean hasPrePage){ $e_ps~{7$
this.hasPrePage = hasPrePage; Wp]EaYt2D
} g|zK%tR_P
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/** zm"\D
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* @return Returns the totalPage. J{Ay(
* Ya_6Zd4O
*/ roA1=G\Q
publicint getTotalPage(){ .( J/*H
return totalPage; 3K{8sFDO
} P$QjDu-
x3P@AC$\
/** 7^iAc6QSy3
* @param totalPage *Q>:|F[vM
* The totalPage to set. j*zK"n
*/ M'HOw)U
publicvoid setTotalPage(int totalPage){ j"V$J8)[
this.totalPage = totalPage; 35>}$1?-6
} |.
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"h2Ny#
} |]q=D1/A
saT9%?4-
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 cDx^}N!
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个PageUtil,负责对Page对象进行构造: w=`z!x![/
java代码: O)Qz$
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/*Created on 2005-4-14*/ e?YbG.(E9
package org.flyware.util.page; y#0w\/<
lkm(3y@']A
import org.apache.commons.logging.Log; A!D:Kc3
import org.apache.commons.logging.LogFactory; _y9P]@Q7%
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/** j+9
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* @author Joa (2li:1j
* nADd,|xD3
*/ /ZDc=>)~
publicclass PageUtil { 5\S7Va;W
sV<4^n7
privatestaticfinal Log logger = LogFactory.getLog wb[(_@eZ
_Pkh`}W:
(PageUtil.class); p5l$On
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/** 3~Ln:4[6ID
* Use the origin page to create a new page Q.1ohj0)
* @param page s]c$]&IGG
* @param totalRecords &[RU.Q!_H
* @return 8:% R|b
*/ /6zpVkV
publicstatic Page createPage(Page page, int t {"iIz_S
Elp!,(+&6
totalRecords){ GU3/s&9
return createPage(page.getEveryPage(), bY~ v0kg
'EV *-_k
page.getCurrentPage(), totalRecords); G C'%s
} IFxI>6<&
>#?: x*[
/** ]e.+u
* the basic page utils not including exception md"%S-a_dT
5@$4.BGcF
handler kDq%Y[6Z
* @param everyPage 3(+#^aw
* @param currentPage ?vFh)U
* @param totalRecords k_>{"Rc
* @return page !h!9SE
*/ ^ kvH/ Y&
publicstatic Page createPage(int everyPage, int MjB[5:s
"6yiQ\`J
currentPage, int totalRecords){ Jt6J'MOq
everyPage = getEveryPage(everyPage); bFezTl{M
currentPage = getCurrentPage(currentPage); 5V~p@vCx
int beginIndex = getBeginIndex(everyPage, A=UIN!
Fz&ilB
currentPage); ]Rh(=bg
int totalPage = getTotalPage(everyPage, 1fv~r@6s
i[{]
LiP
totalRecords); yrAzD=
boolean hasNextPage = hasNextPage(currentPage, (Fzh1#
lzG;F]
totalPage); `HG19_Z
boolean hasPrePage = hasPrePage(currentPage); 4QAIQQS
WN+Jf
returnnew Page(hasPrePage, hasNextPage, _|3TC1N$n
everyPage, totalPage, ACO4u<M)
currentPage, VtiqAh}4
IB{ZE/
beginIndex); WV1 Z
} 6 v^
qLi9ym, ]
privatestaticint getEveryPage(int everyPage){ |7zP8
return everyPage == 0 ? 10 : everyPage; _F@p53WE
} "jO3Y/>S
5jV97x)BGx
privatestaticint getCurrentPage(int currentPage){ :IVMTdYf
return currentPage == 0 ? 1 : currentPage; o?K|[gNi
} 6bKO;^0
Dh No +"!z
privatestaticint getBeginIndex(int everyPage, int Sn2Ds)Pfx3
qMES<UL>
currentPage){ gH^$Y~Lx
return(currentPage - 1) * everyPage; xg,]M/J
} s9kLB.
Q\#{2!I
privatestaticint getTotalPage(int everyPage, int 6'Yn|A
b+].Uc
totalRecords){ eH%L?"J~:
int totalPage = 0; ?lDcaI>+n
}<ONx g6Kb
if(totalRecords % everyPage == 0) l$VxE'&LQ
totalPage = totalRecords / everyPage; w2N3+Tkg
else >xV<nLf/
totalPage = totalRecords / everyPage + 1 ; &rztC]jF
R P:F<`DB|
return totalPage; ]Wd`GI
} e=o{Zo?H=
mERrcY Y{
privatestaticboolean hasPrePage(int currentPage){ h2"|tTm,a
return currentPage == 1 ? false : true; j%Z{.>mJ
} !N8)C@=
gSr}p$N
privatestaticboolean hasNextPage(int currentPage, bq3fiT9
BQ9`DYI b
int totalPage){ bI]UO)
return currentPage == totalPage || totalPage == \As oeeF
HS6Imi
0 ? false : true; s>@#9psm
} 2Cd
--W+=
6"Lsui??
~26s7S}
} FK@ f'
'+!S|U,{
oIvnF:c
lii]4k+z
x1:Pj
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 52MCU l
r($_>TS&"
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 foz5D9sQ
B}q
做法如下: ?$J7%I@
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 |c
oEBFG
MeI2i
的信息,和一个结果集List: &@W4^-9
java代码: 2&gVZ z
Xh0wWU*
c[h'`KXJf-
/*Created on 2005-6-13*/ g/l0}%
package com.adt.bo; NT;x1
O~#uQm
import java.util.List; >2lAy:B5
~w1{zxs
import org.flyware.util.page.Page; uZ/7t(fy
N{^>MRK=5
/** l|vWeBs
* @author Joa n=G>y7b
*/ BK(pJNBh
publicclass Result { c3zT(FgO>N
/m
Q2;*|
private Page page; }+{*, z
=nvAOvP{?
private List content; *>GIk`!wM
s3Krob`C5
/** )iEa2uJ
* The default constructor 5:l*Ib:s7
*/ E+m]aYu"
public Result(){ 9B+ zJ Vte
super(); Ej+]^t$\
} h\=p=M
{
OxAY_
/** jMf 7J
* The constructor using fields 'HQ7
|Je
* }RA3$%3
* @param page GP{$v:RG
* @param content "rjv5*z^&
*/ "#-Nqq
public Result(Page page, List content){ mmrW`~-
this.page = page; "[Qb'9/Jc
this.content = content; h;EwkbDQg>
} nE]~E xr
x2j/8]'o
/** (o x4K{
* @return Returns the content. 2vqmsl?
*/ %A)-m 69
publicList getContent(){ oh7#cFZZ0
return content; {t844La"
} bmj8WZ
/<(*/P,>
/** y:g7'+c
* @return Returns the page. x{NNx:T1
*/ + ZR(
public Page getPage(){ ^MW\t4pZ
return page; ,bZ"8Z"lss
} +CnyK(V
|D;_:x9
/** HA^jk%53
* @param content U^M@um M
* The content to set. E8T"{
R80
*/ #<a_: m)@
public void setContent(List content){ )(h&Q?
Ar
this.content = content; %~#!NX
} r{K\(UT]!
Bs+c2R
/** pu/m8
* @param page F=oHl@
* The page to set. [2GXAvXsT
*/ M1AZ}bc0]
publicvoid setPage(Page page){ zW"~YaO%C
this.page = page; @9OeC
O
} G 2%
} OW+ e_im}
94T}iY.
D^66p8t
8_xnWMOe
jd ["eI
2. 编写业务逻辑接口,并实现它(UserManager, o"'iXUJ
%B#hb<7}
UserManagerImpl) Z|2Eb*
java代码: &mh Ln4^
'R^iKNPs
]s*5[=uc2
/*Created on 2005-7-15*/ b%Wd<N2
package com.adt.service; YHs?QsP
5a=nF9/
import net.sf.hibernate.HibernateException; .cw!ls7d
"DVt3E
import org.flyware.util.page.Page; 25x cD1*
wn
&$C0
import com.adt.bo.Result; HA$Y1}
r#LnDseW
/** y._'K+nl
* @author Joa sW;7m[o
*/ rs[?v*R74
publicinterface UserManager { @4;HC=~
%
2I
public Result listUser(Page page)throws "Jb3&qdU
LWD.
HibernateException; V-[2jC{
^[ET&"
} ;LHDh_.pX
$ I#7dJ"*
`Jn,IDq
%/P=m-K
0;}Aj8Fle
java代码: ?sV[MsOsC
Kn']n91m
bX7EO 8
/*Created on 2005-7-15*/ Xa4GqV9M/-
package com.adt.service.impl; FI\IY
R
6H0W`S0a
import java.util.List; R"NGJu9
>OT\~C
import net.sf.hibernate.HibernateException; LRWOBD
5!<o-{J[(=
import org.flyware.util.page.Page; #-,g&)`]
import org.flyware.util.page.PageUtil; aIQOs
;U
|NmC +
import com.adt.bo.Result; e[s5N:IUd3
import com.adt.dao.UserDAO; /4yOs@#
import com.adt.exception.ObjectNotFoundException; 0[.3Es:_
import com.adt.service.UserManager; 8GY.){d!l
e{5,'(1]
/** xFOBF")
* @author Joa EY]a6@;
*/ :JR<SFjm
publicclass UserManagerImpl implements UserManager { Lj4&_b9
u2 7S%2P
private UserDAO userDAO; 5Yl6?
QW2?n`Fa9-
/** |Td_S|:d
* @param userDAO The userDAO to set. 4K E)g
*/ ^b=XV&{q
publicvoid setUserDAO(UserDAO userDAO){ sD2
^_w6j
this.userDAO = userDAO; (s088O
} oB4#J*
.vK.XFZ8R
/* (non-Javadoc) qh$X^%g
* @see com.adt.service.UserManager#listUser *.8JP
_D-5}a"
(org.flyware.util.page.Page) 3g;T?E
*/ YX_vv!-]
public Result listUser(Page page)throws A]j}'
u)7*Rj^
HibernateException, ObjectNotFoundException { L%f;J/
int totalRecords = userDAO.getUserCount(); 57U%`
if(totalRecords == 0) B3Mx,uXT\
throw new ObjectNotFoundException f4
Q(
1(C
r
^MiRa
("userNotExist"); mk\i}U>`
page = PageUtil.createPage(page, totalRecords); _e_4Q)z-a
List users = userDAO.getUserByPage(page); x:qr \Rz
returnnew Result(page, users); lcCJ?!lsSW
} 6%%PP8.F
2% %|fU9
} [@<G+j
u%xDsTDP
U%q:^S%#eG
v`SY6;<2
o_O+u%y
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 N#UXP5C(
b_vVB`>
询,接下来编写UserDAO的代码: P% Q@9kO>
3. UserDAO 和 UserDAOImpl: .liyC~YW
java代码: *="m3:c'J
9\>sDSCx
iD<6t_8),
/*Created on 2005-7-15*/ \e|U9;Mf
package com.adt.dao; izf~w^/
fe';b[q)#
import java.util.List; JR)/c6j
SF^x=[ir
import org.flyware.util.page.Page; .EG*+,
odpUM@OAW
import net.sf.hibernate.HibernateException; |Ytg
=53bLzr
/** )tD6=Iz^5
* @author Joa "XhOsMJ
*/ *> KHRR<N
publicinterface UserDAO extends BaseDAO { gQ>2!Qc a-
r4?b0&Xq
publicList getUserByName(String name)throws 5>P7]?U.]
wyzOcx>M
HibernateException; |!Fk2Je,
&n|*uLn
publicint getUserCount()throws HibernateException; zP&q7 t;>
[f/.!@sj
publicList getUserByPage(Page page)throws um[!|g/
rrcwtLNbu
HibernateException; {i>Jfl]G}
$/paEn"
} xs%LRF#u
U` hfvTi
8R}K?+]
@!<d0_dnC
V&[eSVY?
java代码: f05=Mc&)
x'qWM/
-`Q}tg>cT
/*Created on 2005-7-15*/ AK *N
package com.adt.dao.impl; HIGNRm
30_ckMG"g
import java.util.List; |sf*hlrJ
|l7%l&!
import org.flyware.util.page.Page; 4P%m>[
8*s7m
import net.sf.hibernate.HibernateException; %iJ|H(P
import net.sf.hibernate.Query; *,lh:
ax_YKJ5#P
import com.adt.dao.UserDAO; ^=0$
9cfR)*Q
/** [@3SfQ
* @author Joa "OL~ul5
*/ X>t3|h
public class UserDAOImpl extends BaseDAOHibernateImpl IqUp4}
Z>2]Xx%
\
implements UserDAO { HabzCH
@Tr&`Hi
/* (non-Javadoc) FVgMmYU
* @see com.adt.dao.UserDAO#getUserByName +9[SVw8
'9J*6uXf.
(java.lang.String) 6^E`Sa!s
*/ o@/xPo|
publicList getUserByName(String name)throws gvyT-XI
>'`Sf ?+|
HibernateException { j[XYj6*d
String querySentence = "FROM user in class %8w9E=
3wC
R|ab}
com.adt.po.User WHERE user.name=:name"; "-
eZZEl(
Query query = getSession().createQuery w!`Umll2
iYKU[UP?
(querySentence); `*yAiv>
query.setParameter("name", name); U-EhPAB@
return query.list(); "K?Q
} 0pN{y}x,
3taa^e.
/* (non-Javadoc) 3SNL5
* @see com.adt.dao.UserDAO#getUserCount() K\&o2lo]
*/ i8~$o:&HT
publicint getUserCount()throws HibernateException { \H4U8)l
int count = 0; ~HmxEk9
String querySentence = "SELECT count(*) FROM O>V(cmqE`
-@M3Dwsi3
user in class com.adt.po.User"; XoItV
Query query = getSession().createQuery VVuR+=.&
i8~r
(querySentence); JE!("]&
count = ((Integer)query.iterate().next c+2%rh1
%idk@~H Cg
()).intValue(); D.*>;5:0'
return count; vM`~)rO@!
} |RhM| i
[X/(D9J
/* (non-Javadoc) Sj-[%D*
* @see com.adt.dao.UserDAO#getUserByPage IU!Ht>
kus}WJ
(org.flyware.util.page.Page) vM4<d>
*/ 64U6C *w+
publicList getUserByPage(Page page)throws >85zQ
1aL
?QpNjsF
HibernateException { S~3\3qt$
String querySentence = "FROM user in class ZHkw6@|
;&f1vi4
com.adt.po.User"; ^od<JD4
Query query = getSession().createQuery K]fpGo
SDBt @=Nl
(querySentence); zn)yFnB!TH
query.setFirstResult(page.getBeginIndex()) `;F2n2@
.setMaxResults(page.getEveryPage()); Fr5 Xp
return query.list(); 3z[$4L'.
} YaL]>.;Z:"
H+l,)Se
} B?6QMC;
#C*&R>IvY
]ii+S"U3
u) *Kws
WRpyr
至此,一个完整的分页程序完成。前台的只需要调用 eVt1d2.O
AK2WN#u@Z
userManager.listUser(page)即可得到一个Page对象和结果集对象 n29(!10Px
ddDS=OfH
的综合体,而传入的参数page对象则可以由前台传入,如果用 lS9n@
NK/4OAt%
webwork,甚至可以直接在配置文件中指定。 wss?|XCI
K+),?Q
?.p
下面给出一个webwork调用示例: lf$Ve
java代码: fKkjn4&W
9lspo~M
-]XP2}#d
/*Created on 2005-6-17*/ r:9gf?(&
package com.adt.action.user; *H2]H@QHN
'*!L!VJ
import java.util.List; &mkpJF/
%Kto.Xq
import org.apache.commons.logging.Log; `fS^
j-_M
import org.apache.commons.logging.LogFactory; n&!+wcJ;Yt
import org.flyware.util.page.Page; SSmHEy*r)
{p/YCch,
import com.adt.bo.Result; ]vo_gKZ
import com.adt.service.UserService; Gr)-5qh
import com.opensymphony.xwork.Action; 9_huI'"p
m{(+6-8|m
/** NP_?f%(
* @author Joa G]*|H0j
*/ 1;wb(DN*c
publicclass ListUser implementsAction{ ;n*J$B
7NF/]y4w
privatestaticfinal Log logger = LogFactory.getLog J?Iq9f
L`3n2DEBf
(ListUser.class); `&*bM0(J
wk[
wNIu
private UserService userService; :&yDqoQKJ
^:cRp9l"7
private Page page; P))^vUt~
FFzH!=7T?
privateList users; rC }}r!!
(vyz;Ob
/* `}8&E(<
* (non-Javadoc) geGeZ5+B
* r<yhI>>;<
* @see com.opensymphony.xwork.Action#execute() PRr*]$\&Mj
*/ fL6e?\Pw
publicString execute()throwsException{ xPC"c*
Result result = userService.listUser(page); p538r[f<
page = result.getPage(); DTY<0Q.
users = result.getContent(); FvXqggfGv
return SUCCESS; `X8@/wf#
} fRHKQ(a#
hh"-w3+
/** ! OE*z $\
* @return Returns the page. IXq(jhm8bL
*/ CqoG.1jJS
public Page getPage(){ G{lcYP O
return page; N|dD!
} ]gP5f @`
>. DC!QV
/** |wp,f%WK
* @return Returns the users. dM]#WBOPy
*/ >K)2NLW\xA
publicList getUsers(){ I=rwsL
return users; Iti0qnBN5
} 7"Mk+'
>^SEWZ_[
/** 9&
* @param page n-afDV
* The page to set. 4 I@p%g&
*/ ,8VU&?`<}
publicvoid setPage(Page page){ a!,r46>$H
this.page = page; oF|N O^H
} n WaNT-
gH7z
/** APSgnf
* @param users b?VV'{4
* The users to set. Yl({)qK{
*/ o"+
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publicvoid setUsers(List users){ 1}g:|Q
this.users = users; %SA!p;
} 9- )qZ
@*O?6>
/** yoS? s
* @param userService K*vU5S
* The userService to set. $8=@R'
*/ erFv(eaDK
publicvoid setUserService(UserService userService){ `f`TS#V
this.userService = userService; P:{<*`q
} Qvqqvk_tv
} `
\ZqgX4
s&tE_
qVgd(?hJ#
h @/;`E[
>k(MUmhX
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, H^AE|U*-G
S4A q'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 Qc"'8kt
=r4!V>
么只需要: 8q^o.+9
java代码: g>j| ]6
SF<Vds}A2
f =s&n}
<?xml version="1.0"?> ?M}S|dsmE
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork l-)Bivoi
Q*ju
sm
1.0//EN" "http://www.opensymphony.com/xwork/xwork- _8fA?q=
JK)qZ=
1.0.dtd"> b{cU<;G)y.
0b-?q&*_
<xwork> p]&j;H.
wij,N(,H
<package name="user" extends="webwork- <+U|dX
_D;@v?n6!O
interceptors"> *@S@x{{s
W>-B [5O&[
<!-- The default interceptor stack name
4na8
x]4Kkpqm
--> Gi?_ujZR
<default-interceptor-ref !@L=;1,
p,!$/Q+l
name="myDefaultWebStack"/> {{{#?~3$7
R[Fn0fnLx
<action name="listUser" 9lzQ\}
q{' ~+Nq
class="com.adt.action.user.ListUser"> z@U}~TvP
<param IOl+t,0x&
l*}FXL
name="page.everyPage">10</param>
dt,3"J
<result M]rO;^ ;6?
\~DM
name="success">/user/user_list.jsp</result> gPXa>C
</action> 2U$"=:Cf
j,-C{ K
</package> /iQ(3F
m
VxO$A,
</xwork> ZFn(x*L
0Y+FRB]u
T0QvnIaP
PlxIfL
~(X(&
Af-UScD%G
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ;)hw%Z]Jj$
K~6e5D7.
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。 xBM>u,0.F
`'4)q}bB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 =
[@)R!3H
:nJgwp()@
?vtX"Fdz
w=_Jc8/.
!!,0'c
我写的一个用于分页的类,用了泛型了,hoho grom\
:1wrVU-?h
java代码: ;y>a
nE}n{
x4kWLy7Sz
/@oLe[Mz$
package com.intokr.util; Ib`-pRU;
#bnb': f
import java.util.List; b{Zpux+
b$JBL_U5Ch
/** 3=.Y,ENM;
* 用于分页的类<br> On_@HQ/FI
* 可以用于传递查询的结果也可以用于传送查询的参数<br> B(5c9DI`
* D ]03eu
* @version 0.01 't (O$
* @author cheng kuMKX`_
*/ /f{$I
public class Paginator<E> { U.oksD9v
privateint count = 0; // 总记录数 _t>"5s&i
privateint p = 1; // 页编号 )}lRd#V
privateint num = 20; // 每页的记录数 ^))RM_ic
privateList<E> results = null; // 结果 p<GR SJIk=
!PUZWO
/** zqySm)o]
* 结果总数 F2I 5qC/
*/ Fd$!wBL
publicint getCount(){ ?+C V1 ]
return count; MXp3g@Cz
} nHOr AD|&
IQ!Fv/I<
publicvoid setCount(int count){ :7.Me;RA
this.count = count; a:rX9-**
} ?A*Kg;IU
Fwg^(;bL
/** t'qL[r%?
* 本结果所在的页码,从1开始 q0xjA
* &%=D \YzG
* @return Returns the pageNo. x_w~G]! /
*/ 0BU=)Swku
publicint getP(){ ja=w5
return p; :z"!kzdJ
} <,@%*G1-
#J\rv'
/** *|:Q%xr-
* if(p<=0) p=1 7L(eh7
* J
m{
* @param p Ve 3 ;
*/ n(ir[w#,]"
publicvoid setP(int p){ EMvHFu
if(p <= 0) ,XKCz ]8V
p = 1; sH#X0fG
this.p = p; _=f=f cl
} epD?K
b'p4wE>
/** "jg@w%~
* 每页记录数量 +b$S~0n
*/ 7:=k`yS,
publicint getNum(){ ~qVz)<
return num; 2?7(A
} Tbbz'b;{
t;qP']2
/** U]6&b
* if(num<1) num=1 &m^@9E)S/
*/ KM,|} .@:
publicvoid setNum(int num){ A$/\1282
if(num < 1) LO%!Z,}
num = 1; o @Z#
this.num = num; }M>rE
} S7iDTG_@t
/%rq
hHs
/** \1%l^dE@
* 获得总页数 ,T{<vRj7_
*/ x34f9!
't
publicint getPageNum(){ VRng=,
return(count - 1) / num + 1; W#w.h33)#6
} ;iYff N
uBnoQ~Qd[z
/** P1>AOH2yG
* 获得本页的开始编号,为 (p-1)*num+1 JgRYljQi2
*/ k;yw#Af8
publicint getStart(){ ]2SF9p_
return(p - 1) * num + 1; \fWW'
} 'cZN{ZMWG
TYns~X_PR
/** "h"NW[R
* @return Returns the results. T<b+s#n4
*/ []kN16F
publicList<E> getResults(){ T Eu'*>g
return results; MmTC=/j
} 1QqHF$S
cW8\d
public void setResults(List<E> results){ F'm(8/A$
this.results = results; i{c@S:&@^
} ;az5ZsvN
D
xG2+(f#C1
public String toString(){ 8P' ana
StringBuilder buff = new StringBuilder e(
X|3h|
{D&9UZm
(); UL@9W6
buff.append("{"); s,]%dG!
buff.append("count:").append(count); v;1F[?@3Y
buff.append(",p:").append(p); kJ:F *34e=
buff.append(",nump:").append(num); U/{6%
Qy
buff.append(",results:").append Zi\['2CG
W-~n|PX8+
(results); 25y6a|`
buff.append("}"); rNOES3[~
return buff.toString(); VR{+f7:}
}
G bP!9I
tiPa6tQ
} E-5_{sc
E ]9\R
Lv[OUW#S