Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n-h2SQl!
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 6E9y[ %+
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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 NLe+
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分页支持类: < bHu9D
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java代码: @PXb^x#k
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package com.javaeye.common.util; zj!&12w%3
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import java.util.List; 5XO eYO{
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publicclass PaginationSupport { V?g@pnN"
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publicfinalstaticint PAGESIZE = 30; Wsn}Y-x
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privateint pageSize = PAGESIZE; 1vcI`8%S+u
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privateList items; zu<8%
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privateint totalCount; )7mX]@
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privateint[] indexes = newint[0]; Ol>"'
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privateint startIndex = 0; ;H#'9p ,2
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public PaginationSupport(List items, int P) fv:a
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totalCount){ >uN`q1?l'
setPageSize(PAGESIZE); \Vis
setTotalCount(totalCount); BX[92~Bq
setItems(items); _VU/j9<+
setStartIndex(0); ,}M@Am0~
} gf]biE"k
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public PaginationSupport(List items, int "7R"(.~>
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totalCount, int startIndex){ 1y5]+GU'`
setPageSize(PAGESIZE); 0NLoqq
setTotalCount(totalCount); <BIj
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setItems(items); Vp
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setStartIndex(startIndex); *|n::9
} { 7y.0_Y
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public PaginationSupport(List items, int t<O5_}R%d
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totalCount, int pageSize, int startIndex){ ;!4Bw"Gg
setPageSize(pageSize); p*10u@,
setTotalCount(totalCount); qC9$xIWq
setItems(items); ^/K\a
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setStartIndex(startIndex); j(|G) F
} 9Vx2VjK2'
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publicList getItems(){ Bcx-t)[
return items; n{F$,a
} ~mc7O
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publicvoid setItems(List items){ q<>
this.items = items; W G2 E3y
} JZp*"UzQr
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publicint getPageSize(){ DpIv <m]
return pageSize; OL]^4m
} \F%5TRoC
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publicvoid setPageSize(int pageSize){ @ViJJ\
this.pageSize = pageSize; \oF79
}
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publicint getTotalCount(){ hd~X c
return totalCount; v\*43RL
} jsSxjf;O
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publicvoid setTotalCount(int totalCount){ )rv5QH`i
if(totalCount > 0){ 7<[p1C*B
this.totalCount = totalCount; o+W5xHe^1
int count = totalCount / ]=p@1
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pageSize; &~P5[[Q
if(totalCount % pageSize > 0) }LS:f,1oGp
count++; $ WA Fr
indexes = newint[count]; Evkb`dU3n
for(int i = 0; i < count; i++){ ^4^1)' %
indexes = pageSize * *>!O2c
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i; Efi@hdEV
} <}b`2/wP
}else{ &| %<=\
this.totalCount = 0; .lfKS!m2
} ud K)F$7
} 'v^CA}
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publicint[] getIndexes(){ ; >3q@9\D
return indexes; i(9=` A}
} e&f9/rfx
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publicvoid setIndexes(int[] indexes){ 2"lD Kjj
this.indexes = indexes; FjIS:9^)t5
} gK/mm\K@
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publicint getStartIndex(){ <A&mc,kj
return startIndex; i"%X[(U7
} |R:gu\gG
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publicvoid setStartIndex(int startIndex){ @sJ[<V
if(totalCount <= 0) ^"\ jIP
this.startIndex = 0; vz:P2TkM
elseif(startIndex >= totalCount) Ed9ynJ~)X
this.startIndex = indexes N2uxiXpQZ=
knX0b$$
[indexes.length - 1]; Vh^fbv`?
elseif(startIndex < 0) Vu '/o[nF>
this.startIndex = 0; Pl<r*d)h
else{ 3o%,8l,
this.startIndex = indexes YQOdwcLG
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[startIndex / pageSize]; R0y={\*B5k
} KE:PRX
} T1hr5V<U
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publicint getNextIndex(){ B"T Z8(<
int nextIndex = getStartIndex() + Z8nj9X$
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pageSize; 1a3rA
if(nextIndex >= totalCount) T6JN@:8
return getStartIndex(); f>ohu^bd
else Zws[}G"7h
return nextIndex; Z`nHpmNM
} 5R}Qp<D[^
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publicint getPreviousIndex(){ LY2oBX@fC
int previousIndex = getStartIndex() - |;_NCy8i3X
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pageSize; B7(~m8:eH7
if(previousIndex < 0) Q[_{:DJA
return0; OiNzN.}d
else _x 'R8/
return previousIndex; pkpD1c^
} IRNL(9H
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} b'Qia'a%
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抽象业务类 *T
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java代码: Y~Y-L<`I
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/** >k,|N4(
* Created on 2005-7-12 J]/TxUE
*/ %`%oupqm+
package com.javaeye.common.business; !"/]<OQ
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import java.io.Serializable; K[0.4+
import java.util.List; A<l8CWv[
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import org.hibernate.Criteria; tGnBx)J|
import org.hibernate.HibernateException; #pu6^NTK
import org.hibernate.Session; !!Z#'Wq
import org.hibernate.criterion.DetachedCriteria; 4s nL((
import org.hibernate.criterion.Projections; =LV7K8FSd
import ;EbGW&T
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org.springframework.orm.hibernate3.HibernateCallback; w2!G"oD
import n4Nb,)M
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org.springframework.orm.hibernate3.support.HibernateDaoS P'f
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upport; {'VP_ZS1v
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import com.javaeye.common.util.PaginationSupport; O6Bs!0,
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public abstract class AbstractManager extends }&D~P>1
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HibernateDaoSupport { qd#?8
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privateboolean cacheQueries = false; _@9[c9bO
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privateString queryCacheRegion; L;zwqdI
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publicvoid setCacheQueries(boolean {Vw+~8
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cacheQueries){ 2g~qVT,
this.cacheQueries = cacheQueries; RUqN,C,m5I
} i'9aQi"G
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publicvoid setQueryCacheRegion(String %jz]s4u$5j
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queryCacheRegion){ |N_tVE
this.queryCacheRegion = m3W:\LTTp
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queryCacheRegion; g^|}e?
} !.1oW(
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publicvoid save(finalObject entity){ T<(1)N1H`
getHibernateTemplate().save(entity); #\s*>Z
} .[&0FHnJ5
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publicvoid persist(finalObject entity){ ~_opU(;f
getHibernateTemplate().save(entity); aX`"V/
} +v.uP [H
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publicvoid update(finalObject entity){ @_s`@,=
getHibernateTemplate().update(entity); Ie{98
} Qt` hUyL
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publicvoid delete(finalObject entity){ ]&6# {I-
getHibernateTemplate().delete(entity); HS> (y2}'
} y4*i
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publicObject load(finalClass entity, K~'!JP8@
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finalSerializable id){ 0_'(w;!wq:
return getHibernateTemplate().load
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(entity, id); Zjqa n
} )!6JSMS
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publicObject get(finalClass entity, },58B
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finalSerializable id){ S_; 5mb+b
return getHibernateTemplate().get Fp'qn'){:#
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(entity, id); <xpOi&l
} R_9 &V!fl
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publicList findAll(finalClass entity){ Zoe>Ow8mE`
return getHibernateTemplate().find("from LXYpP-E
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" + entity.getName()); 58xaVOhb
} Ku;|Dz/=o
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publicList findByNamedQuery(finalString DV+M;rs
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namedQuery){ iMG)zPj
return getHibernateTemplate %smQ`u|
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().findByNamedQuery(namedQuery); vJZ0G:1
} 8vQGpIa,
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publicList findByNamedQuery(finalString query, @1+C*
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finalObject parameter){ ^n8ioL\*i
return getHibernateTemplate AI
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().findByNamedQuery(query, parameter); t^_0w[
} V{!fag
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publicList findByNamedQuery(finalString query, k3[rO}>s
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finalObject[] parameters){ _N8Tu~lqV
return getHibernateTemplate *R9s0;&:
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().findByNamedQuery(query, parameters); ,RmXZnWY
} h>Z NPP8N
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publicList find(finalString query){ oCtg{*vp
return getHibernateTemplate().find $cl[Qcw
;]*V6!6RR
(query); wQ1_Q8 :Z
} 'Br:f_}
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publicList find(finalString query, finalObject s|er+-'
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parameter){ R7)\wP*l5
return getHibernateTemplate().find (!b_o A8V
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(query, parameter); w+A:]SU
} i4<&zj})
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public PaginationSupport findPageByCriteria $db]b
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(final DetachedCriteria detachedCriteria){ $;O-1# ]
return findPageByCriteria #h,7dz.d
*"cK_MH/o
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q6>7{\8l
} #Z;6f{yWf
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public PaginationSupport findPageByCriteria 6yDj1PI
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(final DetachedCriteria detachedCriteria, finalint K4T#8K]aZF
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startIndex){ cnJL*{H<2
return findPageByCriteria '5^$v{
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(detachedCriteria, PaginationSupport.PAGESIZE, m(2(Caz{
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startIndex); Om%HrT
} 9NUft8QB
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public PaginationSupport findPageByCriteria Lj]I7ICNh
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(final DetachedCriteria detachedCriteria, finalint 4)]w"z0Pc
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pageSize, 8]SJ=c"}Xf
finalint startIndex){ $? 'JePC
return(PaginationSupport) '*4>&V.yX
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getHibernateTemplate().execute(new HibernateCallback(){ i4sd29v
publicObject doInHibernate D8S?xK 7[
@.rVg XE=!
(Session session)throws HibernateException { ^oZz,q
Criteria criteria = }Iyr u3M][
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detachedCriteria.getExecutableCriteria(session); 3HtLD5%Q
int totalCount = ?(C(9vO
U,G!u =+
((Integer) criteria.setProjection(Projections.rowCount uj8G6'm%
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()).uniqueResult()).intValue(); Z`_`^ \"
criteria.setProjection 8}B*a;d
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(null); "hE/f~\
List items = C(w?`]Qs
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criteria.setFirstResult(startIndex).setMaxResults iCz0T,
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(pageSize).list(); nqp:nw
PaginationSupport ps = /mdPYV
#F>7@N:5
new PaginationSupport(items, totalCount, pageSize, ^*6So3
}JP0q
startIndex); ] ^f7s36
return ps; 8|-j]
} oK-T@ &-
}, true); MU
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} ywSV4ZtM
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public List findAllByCriteria(final Y 6NoNc]h
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DetachedCriteria detachedCriteria){ "-y2En
return(List) getHibernateTemplate cpIFjb>u{
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().execute(new HibernateCallback(){ E1|> O
publicObject doInHibernate 5g x9W\a ?
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(Session session)throws HibernateException { knX*fp
Criteria criteria = Ffvv8x
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detachedCriteria.getExecutableCriteria(session); fX:)mLnO/
return criteria.list(); mYU7b8x_
} k`j>lhH
}, true); zC@ ziH>{]
} 4t C-msTf
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public int getCountByCriteria(final `.MY"g9
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DetachedCriteria detachedCriteria){ \2UtT@3|C
Integer count = (Integer) SxX2+|0g`g
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getHibernateTemplate().execute(new HibernateCallback(){ U@;W^Mt
publicObject doInHibernate gY\g+df-
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(Session session)throws HibernateException { `[OJ)tHE
Criteria criteria = ZWtlO P#]
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detachedCriteria.getExecutableCriteria(session); ;)6LX-
return N5ph70#y3
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criteria.setProjection(Projections.rowCount +hUS
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()).uniqueResult(); KA[8NPhzZ
} I.4o9Z[?
}, true); 8!R +wy
return count.intValue(); sp&s
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} ;s^br17z~
} WfdM~k\
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用户在web层构造查询条件detachedCriteria,和可选的 +qWrm|O]
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 N7wKaezE
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PaginationSupport的实例ps。 Qb N7sg~~
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ps.getItems()得到已分页好的结果集 cC4 2b2+
ps.getIndexes()得到分页索引的数组 GlVb |O"
ps.getTotalCount()得到总结果数 / LH#
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ps.getStartIndex()当前分页索引 @Sik~Mm_h
ps.getNextIndex()下一页索引 y ~PW_,
ps.getPreviousIndex()上一页索引 3d1$w
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 !ek};~(
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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 6'F4p1VG*I
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一下代码重构了。 WR;)
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我把原本我的做法也提供出来供大家讨论吧: &7fwYV
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首先,为了实现分页查询,我封装了一个Page类: u|G&CV#r
java代码: vqeWt[W
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/*Created on 2005-4-14*/ $ ]fautQlt
package org.flyware.util.page; GKk>;X-
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/** ~!Ar`=
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* @author Joa o 94]:$=~
* Vgj&hdbd
*/ A>bpP
publicclass Page { odPdWV,&*
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/** imply if the page has previous page */ I6.!0.G
privateboolean hasPrePage; +WH|nV~lQ
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/** imply if the page has next page */ sC<
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privateboolean hasNextPage; 8Qo~zO
yF _@^V
/** the number of every page */ C.#\Pz0
privateint everyPage; US.7:S-r"
q^I/
/** the total page number */ h1A/:/_M6
privateint totalPage; pBb fU2p
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/** the number of current page */ 7GFE5>H
privateint currentPage; DHnO ,"
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/** the begin index of the records by the current H[x$65ND
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query */ 0DZ}8"2
privateint beginIndex; R.Uwf
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/** The default constructor */ ;1^([>|
public Page(){ +HpPVuV
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} rsGQ
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/** construct the page by everyPage 9_4bw9A
* @param everyPage nYvx[
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* */ 8M~^/Zc
public Page(int everyPage){ }~akVh`3
this.everyPage = everyPage; -".q=$f
} |Y9mre.Y;
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/** The whole constructor */ \\D(St
public Page(boolean hasPrePage, boolean hasNextPage, V~~4<?=A
>Av[`1a2F
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int everyPage, int totalPage, 45qSt2
int currentPage, int beginIndex){ K.R4.{mo
this.hasPrePage = hasPrePage; :|5\XV)>
this.hasNextPage = hasNextPage; O^L#(8bC
this.everyPage = everyPage; ;Pd nE~
this.totalPage = totalPage; 2d:5~fEJp
this.currentPage = currentPage; [dXpz^Co
this.beginIndex = beginIndex; C@ns`Eh8w
} BB .^[:,dA
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/** `Vf k.OP
* @return gx55.}
* Returns the beginIndex. xl]1{$1M
*/
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publicint getBeginIndex(){ +{5y,0R
return beginIndex; e{}oQK
} )<+t#5"
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/** ->rr4xaK C
* @param beginIndex t!285J8tn
* The beginIndex to set. kgZiyPcw
*/ YPU*T&~
publicvoid setBeginIndex(int beginIndex){ N+3]C9 2o
this.beginIndex = beginIndex; Y48MCL
} 2|re4
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/** %p(!7FDE2n
* @return ~M!9E])
* Returns the currentPage. Y;uQq-C P
*/ N6%wHNYZ
publicint getCurrentPage(){ !Y95e'f.x
return currentPage; @L/p
} b rpsZU
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/** &$V&gAN
* @param currentPage ;J&p17~T9
* The currentPage to set. #=81`u
*/ ]aDU* tk
publicvoid setCurrentPage(int currentPage){ ?\.DG`Zxc
this.currentPage = currentPage; D00v"yp%%
} K
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/** G oHdhne3
* @return +;|" #
* Returns the everyPage. |vUjoa'.7E
*/ v&]k8Hc-
publicint getEveryPage(){ ~5@bWJ
return everyPage; wa f)S=
} ":meys6t#
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/** }9FAM@x1K&
* @param everyPage iS@+qWo1
* The everyPage to set. sPxDo?1x-
*/ U{[ g"_+~
publicvoid setEveryPage(int everyPage){ ^OZ*L e
this.everyPage = everyPage; E8LZ%
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} 6dlV:f_\y
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/** %={[e`,
* @return {n'+P3\T:
* Returns the hasNextPage. .gP}/dj
*/ ;+3XDz
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publicboolean getHasNextPage(){ 7+2DsZ^6MW
return hasNextPage; KM:k<pvi
} AS-%I+ A
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/** g[%^OT#
* @param hasNextPage u$%;03hJ
* The hasNextPage to set. pcC/$5FQ
*/ hziPHuK9,
publicvoid setHasNextPage(boolean hasNextPage){ vvwQ/iJO4Q
this.hasNextPage = hasNextPage; \\d!z-NOk?
} >gSiH#>
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/** =Y]'wb
* @return VsjE*AJpe
* Returns the hasPrePage. bSvr8FY3d
*/ >2BWie?T
publicboolean getHasPrePage(){ H)rE-7(f!
return hasPrePage; 9,J^tN@^
} 0YA
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/** ??
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* @param hasPrePage E-v#G~
* The hasPrePage to set. (`cXS5R
*/ AbA_s I<;
publicvoid setHasPrePage(boolean hasPrePage){ !V~,aoKTj
this.hasPrePage = hasPrePage; VoG:3qN
} 69iY)Ob/
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/** {?YBJnG}x
* @return Returns the totalPage. u_ *DS-
* (O-.^VV
*/ $TZjSZ1w
publicint getTotalPage(){ [yn\O=%5
return totalPage; \NF5)]:
} b
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/** /BQB7vL
* @param totalPage A8T75?lL(
* The totalPage to set. MY w3+B+Jj
*/ 2AdO
publicvoid setTotalPage(int totalPage){ AA &>6JB{
this.totalPage = totalPage; W20H4!G
} oksAQnQe
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} H-C$Jy)f"
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h#~\-j9>
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 Qk[YF
08MY=PC~R
个PageUtil,负责对Page对象进行构造: (,XbxDfM
java代码: VBq|j"o0"
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/*Created on 2005-4-14*/ e$l*s/"0t
package org.flyware.util.page; 8$~^-_>n/
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import org.apache.commons.logging.Log; Wo2W/{
import org.apache.commons.logging.LogFactory; @aC9O9|~
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/** 4r tNvf5`
* @author Joa zXZXp~7)
* ~kp,;!^vr
*/ YwU[kr-i
publicclass PageUtil { *o}7&Hw#9f
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privatestaticfinal Log logger = LogFactory.getLog xtFGj,N
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(PageUtil.class); c1sVdM}|
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/** E2i'lO\P
* Use the origin page to create a new page :>K8oE
* @param page t->I# t7
* @param totalRecords :ZsAWe{%,J
* @return 9,cMb)=0
*/ n%K^G4k^
publicstatic Page createPage(Page page, int rGmxK|R
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totalRecords){ 1{-yF :A
return createPage(page.getEveryPage(), bR'UhPs-8;
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page.getCurrentPage(), totalRecords); oYAHyCkVq
} %Xe 74C"
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/** Px?zih!6
* the basic page utils not including exception HB*H%>L{"B
t_kRYdW 9
handler Y+nk:9
* @param everyPage ' '<3;
* @param currentPage gaWJzK
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* @param totalRecords i)q8p
* @return page E(!b_C&
*/ [=]LR9c4
publicstatic Page createPage(int everyPage, int ,B1~6y\b
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currentPage, int totalRecords){ h|%a}])G)
everyPage = getEveryPage(everyPage); zGtv(gwk
currentPage = getCurrentPage(currentPage); ht_'GBS)
int beginIndex = getBeginIndex(everyPage, ZtGtJV"H
Vb,'VN%
currentPage); x(7Q5Uk\
int totalPage = getTotalPage(everyPage, td 5!
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!,9;AMO
-
totalRecords); ")Qhg-l
boolean hasNextPage = hasNextPage(currentPage, ;5tQV%V^Q
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totalPage); N
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boolean hasPrePage = hasPrePage(currentPage); fL~@v-l#~
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returnnew Page(hasPrePage, hasNextPage, ymb{rKkN3
everyPage, totalPage, m[qW)N:w
currentPage, SNc $!
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beginIndex); )1gOO{T]h?
}
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privatestaticint getEveryPage(int everyPage){ I9L7,~s
return everyPage == 0 ? 10 : everyPage; ~oz??SX
} 3c+ps;nh
Ya;y@44
privatestaticint getCurrentPage(int currentPage){ IG90mpLX
return currentPage == 0 ? 1 : currentPage; 9`td_qh
} )Wy:I_F351
tt A'RJ
privatestaticint getBeginIndex(int everyPage, int &AnWMFo
.oqe0$I
currentPage){ s)G?5Gz
return(currentPage - 1) * everyPage; {ObUJ3
} C#TP1~6
C."\ a_p
privatestaticint getTotalPage(int everyPage, int ;:
0<(!^*
ldt]=Sqy
totalRecords){ AP+%T
int totalPage = 0; /vs79^&
Ch_eK^ g1
if(totalRecords % everyPage == 0) RMHJI6?LB
totalPage = totalRecords / everyPage; e2kW,JV/<$
else }H:wgy`
totalPage = totalRecords / everyPage + 1 ; LZDJ\"a-
INY?@in
return totalPage; rE%HNPO
} h_5CWQSi
O!P7Wu
privatestaticboolean hasPrePage(int currentPage){ S]Ye`
return currentPage == 1 ? false : true; 6&o?#l;|
} *p0Kw>
Sym}#F\s
privatestaticboolean hasNextPage(int currentPage, ]]P@*4!
4"veq rC
int totalPage){ ` <u2 N
return currentPage == totalPage || totalPage == @H$Sv
PR7B
Cxm
0 ? false : true; sh*/wM
} kS4YxtvB
RZ|M;c
C!U$<_I\2
} >D%
! ~tf0aY
Q5HSik4
\_x~lRqJJ
54#P
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。
'Pxq>Os
CU:HTz=
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 g3f;JB
QUDpAW
做法如下: NAOCQDk{
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7^C&2k5G
iN_P25Z<r
的信息,和一个结果集List: gYBMi)`RT
java代码: v.hQ9#:
$HCgawQ
*U-:2uf
/*Created on 2005-6-13*/ T+oOlug
package com.adt.bo; B!U;a=ia
5A+@xhRf
import java.util.List; *T~b
ox
1024L;
import org.flyware.util.page.Page; e*Y<m\*
^!z(IE'
/** MT6"b
* @author Joa Yl=-j
*/ >[;L.
publicclass Result { 8erG](
+J#8wh
private Page page; 5fRr d;
B$qTH5)W
private List content; 5?[hr5E.E
>+DMTV[O
/** \BX9Wn*)a
* The default constructor _l2_) ~
*/ [^D>xD3B2
public Result(){ L1f=90
super(); x_CY`Y
} MRg Ozg
}rUAYr~V Z
/** iH~A7e62OZ
* The constructor using fields 7$x%A&]
* 1OV] W
f
* @param page [SD
mdr1T$
* @param content -/2B fIq
*/ @$iZ9x6t
public Result(Page page, List content){ m6#a{
this.page = page; 'Va<GHr>+
this.content = content; .PV(MV
} d2TIG<6/
w@Asz9Lq%
/** Z}{]/=h
* @return Returns the content. Xppv
*/ ;G[0%z+*
publicList getContent(){ ;WAa4r>
return content; 4I .'./u
} OZC
yg/K
jFip-=T{4
/**
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* @return Returns the page. +v$W$s&b-h
*/ 0+u>"7T
public Page getPage(){ v7Ps-a)
return page; H23 O]r
} sPVE_n
,SNt*t1"
/** 3hxV`rb
* @param content 6}VFob#h8
* The content to set. e=aU9v
L
*/ |KVVPXtq%C
public void setContent(List content){ <sw=:HU
this.content = content; A3*(c3
} NCY2^
hn\d{HP
/** h-RhmQA=Iz
* @param page Sk)lT^by
* The page to set. (&v,3>3]
*/ }!?RB v'W
publicvoid setPage(Page page){ Gs,e8ri!
this.page = page; >2=
Y 35j
} 7WUvO
} nA{yH}D4
_!!Fg%a5"R
9_?e, Q
O&&_)
~<~
~C#R
2. 编写业务逻辑接口,并实现它(UserManager, 74N3wi5B
z&Aya*0v`
UserManagerImpl) t\a|Gp W
java代码: p&5>j\uJ1&
H?!DcUg CC
CJ7S5
/*Created on 2005-7-15*/ qVI0?B
x
package com.adt.service; =9W\;xE S
rV4K@)~
import net.sf.hibernate.HibernateException; sH_,P
3~V.
import org.flyware.util.page.Page; Lis>Qr
13w(Tf
import com.adt.bo.Result; 4T;<`{]
$d!Vx m
/** M] +.xo+A
* @author Joa bM5o-U#^ C
*/ (xoYYO
publicinterface UserManager { uubIL+
17,mqXX>
public Result listUser(Page page)throws +GL$[ 5G
SWY
HibernateException; RgL>0s
+
d 3
} pT3icy!A=
$45.*>,
k3nvML,bv
.Gvk5Wn
, ,ng]&%i
java代码: eV/oY1B]<
Dte5g),R
HyOrAv
<
/*Created on 2005-7-15*/ UqyW8TCf?
package com.adt.service.impl; q mv0 LU
$COjC!M
import java.util.List; \v5;t9uBZ
c#"t.j<E}
import net.sf.hibernate.HibernateException; zH6@v+gb
2%6 >)|
import org.flyware.util.page.Page; B /w&Lo
import org.flyware.util.page.PageUtil; F?05+
#p55/54ZI
import com.adt.bo.Result; iU37LODa2T
import com.adt.dao.UserDAO; M8<Vd1-5
import com.adt.exception.ObjectNotFoundException; J=gFiBw
import com.adt.service.UserManager; >C!^%e;m
@SpP"/)JY
/** ZTz07Jt
* @author Joa |FM*1Q[1
*/ <Z<meB[g
publicclass UserManagerImpl implements UserManager { a'/i/@h
M?L$xE_&
private UserDAO userDAO; g}W|q"l?i
;b~\[
/** (_<,Oj#*S
* @param userDAO The userDAO to set. t89Tt @cf
*/ a!-J=\>9
publicvoid setUserDAO(UserDAO userDAO){ c.b| RM0;
this.userDAO = userDAO; **kix
} >:> W=
FKz5,PeL
/* (non-Javadoc) wT6zeEV~*
* @see com.adt.service.UserManager#listUser <F;+A{M)
`]XI Q\ *
(org.flyware.util.page.Page) 7pciB}$2
*/ qt*+ D
public Result listUser(Page page)throws X!/Sk1
>5:O%zQ@
HibernateException, ObjectNotFoundException { zBTW&
int totalRecords = userDAO.getUserCount(); :?BK A0E
if(totalRecords == 0) S\<i`q
throw new ObjectNotFoundException ^.\O)K {h
M}# DX=NZc
("userNotExist"); H?8'(
page = PageUtil.createPage(page, totalRecords); (.V),NKG
List users = userDAO.getUserByPage(page); dXQ C}JA
returnnew Result(page, users); F.5fasdX'
} #Xox2{~
h_S>Q
} L YF|
Q= fl!>P
%dg[ho
,xVAJ6_#
(IVhj^dQm
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 oD9n5/ozo
_"L6mcI6
询,接下来编写UserDAO的代码:
o0f`/
6o
3. UserDAO 和 UserDAOImpl: y32$b,%Xi,
java代码: KNd<8{'.
L/exR6M7
3oMHy5
/*Created on 2005-7-15*/ S7Ty}?E@
package com.adt.dao; B 5|\<CF
}UB@FRPF
import java.util.List; S#y[_C?H
G%t>Ll``C
import org.flyware.util.page.Page; PC<_1!M]
@r/~Y]0Ye5
import net.sf.hibernate.HibernateException; qJrKt=CE
$=N?[h&4
/** /B~[,ES@1
* @author Joa J:glJ'4E
*/ ,r;xH}tbi
publicinterface UserDAO extends BaseDAO { 6{HCF-cQd
u"*DI=pwb
publicList getUserByName(String name)throws 3cL
iZ%6^
,:A;4
HibernateException; ~Ss,he]Er
R=LiB+p
publicint getUserCount()throws HibernateException; D\-\U
E/
FZj>N(
publicList getUserByPage(Page page)throws %}VH5s9\
!h7.xl OpN
HibernateException; @e
GBF
Ns
Gb\PubJ
} Coe/ 4!$M
Tgr,1)T
+)"Rv%.
m)Kg6/MV.
*??lwvJp
java代码: A+0-pF2D
:1>?:3,`
X&?s:A
/*Created on 2005-7-15*/ @i; )`k5b
package com.adt.dao.impl; 8$
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J4"Fj, FS
import java.util.List; TjEXR$:<
PVBz~rG
import org.flyware.util.page.Page; 4>>=TJ!M
kygw}|, N
import net.sf.hibernate.HibernateException; =x\`yxsG
import net.sf.hibernate.Query; -PE_q Z^
nm,LKS7
import com.adt.dao.UserDAO; *kl :/#
/D3{EjUE=
/** D![v{0 er
* @author Joa 1^}I?PbqV
*/ E>|X'I?r^
public class UserDAOImpl extends BaseDAOHibernateImpl +SH{`7r
Lz'VQO1U=
implements UserDAO { WQ.0} n}d
*{DTxEy
/* (non-Javadoc) <ukBAux,D
* @see com.adt.dao.UserDAO#getUserByName GT&}Burl/n
4V')FGB$
(java.lang.String) i.vH$
*/ 3c=kYcj
publicList getUserByName(String name)throws Go)$LC0Mi
@i1e0;\
HibernateException { tg/UtE`V
String querySentence = "FROM user in class m0"K^p
`GCoi ?n7
com.adt.po.User WHERE user.name=:name"; ,RV
qYh(-|
Query query = getSession().createQuery ;=ddv@
N>!:bF
(querySentence); \!-BR0+y;
query.setParameter("name", name); 147QB+cE
return query.list(); <W"W13*j!
} WEimJrAn
'+PKGmRW
/* (non-Javadoc) hJ@vlMW
* @see com.adt.dao.UserDAO#getUserCount() gsk?
!D
*/ kOYUxr.b
publicint getUserCount()throws HibernateException { l#'V
SFm&
int count = 0; HeRi67
String querySentence = "SELECT count(*) FROM <xOX+D
zfeT>S+
user in class com.adt.po.User"; iVXt@[
Query query = getSession().createQuery K3yQ0k
|
!GqFX+!Ju
(querySentence); ,@`?I6nKy
count = ((Integer)query.iterate().next Ttluh
*
8D='N`cN+
()).intValue(); Jj"{C]
return count; {>f"&I<xw
} 1@F-t94I
ju"z
/* (non-Javadoc) uzy5rA==
* @see com.adt.dao.UserDAO#getUserByPage 9P?0D
pM?;QG;jA
(org.flyware.util.page.Page) JE?rp1.
*/ 3e_tT8
publicList getUserByPage(Page page)throws /Nf{;G!kg
;w7 mr1
HibernateException { y6XOq>
String querySentence = "FROM user in class )U@9dV7u
p)y5[HX
com.adt.po.User"; j/O~8o&
Query query = getSession().createQuery i5VZ,E^E
)6OD@<r{
(querySentence); ?[ xgt)
query.setFirstResult(page.getBeginIndex()) ;CYoc4e
.setMaxResults(page.getEveryPage()); _fHC+lwN
return query.list(); B/twak\
} sdFHr4
`H+"7SO
} yqT !A
j/ 5
tn]nl!_@
U'fP
7' G;ijx
至此,一个完整的分页程序完成。前台的只需要调用 J2bvHxb Rd
j#l=%H
userManager.listUser(page)即可得到一个Page对象和结果集对象 t#k]K]
z*\_+u~u
的综合体,而传入的参数page对象则可以由前台传入,如果用 7oE0;'
2}hJe+#v
webwork,甚至可以直接在配置文件中指定。 A3jxjQ
Pe`(9&iT.
下面给出一个webwork调用示例: C8U3+ s
java代码: T+kV~ w{
fkA+:j~z_
mq`/nAmt
/*Created on 2005-6-17*/ 6_CP?X+T
package com.adt.action.user; Npp YUY
ov6xa*'a
import java.util.List; sy: xA w
4Yj1Etq.E
import org.apache.commons.logging.Log; .ZTvOm'mB^
import org.apache.commons.logging.LogFactory; Ez3fL&*
import org.flyware.util.page.Page; {w@qFE'b
o`bch?]
import com.adt.bo.Result; F-_u/C]
import com.adt.service.UserService; d>QFmsh-
import com.opensymphony.xwork.Action; HBlk~eZ
50,'z?-_
/** !nv wRQ
* @author Joa FY1iY/\Cn
*/ 1-2hh)
publicclass ListUser implementsAction{ n(:<pz
mUYRioNj
privatestaticfinal Log logger = LogFactory.getLog ZT0\V
]!B
HI.*xkBXl&
(ListUser.class); 66yw[,Y
-ss= c #
private UserService userService; USg"wJY
acd[rjeT
private Page page; A;oHji#*
ci0A!wWD
privateList users; ['d9sEv .
{v?Q9
/* 'p@f5[t
* (non-Javadoc) g`Z=Y7jLH
* RRL{a6(?
* @see com.opensymphony.xwork.Action#execute() @!8aZB3odt
*/ TEtmmp0OD
publicString execute()throwsException{ 8q2a8I9g
Result result = userService.listUser(page); mQ"~x]
page = result.getPage(); "Ep"$d
users = result.getContent(); -+R,="nRQ
return SUCCESS; vObZ|>.J~O
} MmF&jd-=
w#A)B<Y/"
/** [!'+}
* @return Returns the page. 6Yu:v
*/ &f*orM:
public Page getPage(){ b^o4Q[
return page; b8mH.g&l
} PDNl]?
VYk:c`E
/** d0El2Ct8
* @return Returns the users. S
'a- E![
*/ kDmm
publicList getUsers(){ ?nU<cx h
return users; n]%-2`}(
} |[\;.gT K
N /4E
~^2
/** 2+1ybOwb
* @param page V9c.(QY|f
* The page to set. <c+.%ka
*/ 1`cH
E Aa
publicvoid setPage(Page page){ 2t= =<x
this.page = page; [vg&E
)V
} .#[ 9q-
HD j6E"
/** FI.te3i?7
* @param users O?uICnmi6
* The users to set. -3K h
>b)
*/ 6o't3Peh
publicvoid setUsers(List users){ U4D7@KY +m
this.users = users; rH@Rh}#yp
} \8vP"Kr
a4Q@sn;]
/** }(EH5jZ'
* @param userService e3I""D{)[=
* The userService to set. /jv/qk3i
*/ zsL@0]e&
publicvoid setUserService(UserService userService){ D|uvgu2
this.userService = userService; GppCrQ%Ra|
} =LW!$p
} N'
hT
lY%I("2=
N>mW64_H)
.j}]J:{%
ORM>|&
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, YWZ;@,W
@G5T8qwN
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 VjQ&A#
H 0l1=y
么只需要: HNzxFnh
java代码: ?f?5Kye
C'6I< YX
Al>d
21U
<?xml version="1.0"?> qBEp |V
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Tzq@ic#!B
+nYFLe
1.0//EN" "http://www.opensymphony.com/xwork/xwork- d$!Q6ux;
g=Xf&}&=x
1.0.dtd"> ~\":o:qyc
{>>X3I
<xwork> 3?Pg
;
mjeJoMvN)H
<package name="user" extends="webwork- b3A0o*
R1];P*>%gZ
interceptors"> BT7{]2?&V
gInh+XZs
<!-- The default interceptor stack name *EWWN?d
+O}Ik.w
--> <4}m:
<default-interceptor-ref n!)$e;l
3H2~?CaJ
name="myDefaultWebStack"/> 0jTReY-W
;V,L_"/X
<action name="listUser" eL3 _Lz
zxR]+9Zh
class="com.adt.action.user.ListUser"> j=r1JV
@
<param IeYYG^V<A
g~hMOI?KK^
name="page.everyPage">10</param> 2`o
@L
<result B+W7zv
oE 'P
name="success">/user/user_list.jsp</result> 10SI&O
</action> ?I+L
8dE0y P
</package> qTJhYxm
(&}[2pb!
</xwork> )Q 2IYCj{
U5Hi9fe
]]j^
yE}\4_0I/
&8$v~
*5)UIRd
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 >Hf{Mx{<
\jfK']P/H
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。 (/:m*x*6
{JE [
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 IkCuw./
"6B@V=d
T^v763%
PaCCUF
BA@E
我写的一个用于分页的类,用了泛型了,hoho 56;u7
Oe5rRQ$O
java代码: $d<NN2
>@vu;j\*E5
b-u@?G|<
package com.intokr.util; 9nFL70
VZ9 p "
import java.util.List; N/tcW
gFR}WBl/
/** )re<NE&M
* 用于分页的类<br> 63l3WvoK
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~F"S]
* j
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* @version 0.01 o/Ismg-p
* @author cheng 'z|Da &d P
*/ UoxlEec
public class Paginator<E> { nxZz{&
privateint count = 0; // 总记录数 C19N0=
privateint p = 1; // 页编号 Pe<VPf9+
privateint num = 20; // 每页的记录数 wgFX')l:
privateList<E> results = null; // 结果
SkjG}
2uj
.*
/** HE&)N
clY
* 结果总数 ~1O|4mssS
*/ N@d~gE&^
publicint getCount(){ XvI~"}
return count; yCQvo(V[F
} sxT&T=7
I=!kPuw
publicvoid setCount(int count){ WARiw[
this.count = count; |[`YGA4
} $_S-R
3L\
z~t0l
/** \Oq2{Sx\
* 本结果所在的页码,从1开始 Lm[,^k
* uE1;@Dm+
* @return Returns the pageNo. #D9.A7fCc5
*/ k8?._1t
publicint getP(){ wUaWF$~y
return p; [/a
AH<9b
} ]'5Xjcx
_d 6'f8[&
/** p{,#H/+J
* if(p<=0) p=1 }u;K<<h:
* n.g-%4\q
* @param p qSP&Fi
*/ [H*JFKpx
publicvoid setP(int p){ |%|03}Q
if(p <= 0) -riX=K>$
p = 1; c^I^jg2v
this.p = p; ==Egy:<:Q
} /4T6Z[=s
35l%iaj]G5
/** xt|^~~ /
* 每页记录数量 #LR4%}mg
*/ '8]p]#l
publicint getNum(){ &dtst??
return num; XP)^81i|
} #1-WiweO
-J3~j kf
/** sJZ2e6?n
* if(num<1) num=1 b? o
*/ uXc;!*
publicvoid setNum(int num){ Y\9}LgIvr
if(num < 1) iyn9[>je
num = 1; ^=eC1bQA
this.num = num; x*H#?.E
} IL|Q-e}Ol
Xqw}O2QQ1
/** %tP*_d:
* 获得总页数 pq`uB
*/ B>nj{W<o
publicint getPageNum(){ joI) 6c
return(count - 1) / num + 1; KRL.TLgq)
} q;,lv3I
bkd`7(r
/** Nf([JP% 4
* 获得本页的开始编号,为 (p-1)*num+1 0Fb];:a
*/ 9)7$U QY
publicint getStart(){ AJ%E.+@=r
return(p - 1) * num + 1; "AUSgVE+h
} !~|-CF0z=
S L
5k^|
/** G:1d6[Q5{
* @return Returns the results. ":
vGs_$
*/ y@!M<#SEzG
publicList<E> getResults(){ 0Agse)
return results; <yipy[D
} F
,472H
>OaD7
public void setResults(List<E> results){ d@ K-ZMq
this.results = results; O2 >c|=#
} 5TJd9:\Af
bY#BK_8 :
public String toString(){ Dy.i^`7\
StringBuilder buff = new StringBuilder N" L&Z4Z
l$&~(YE f
(); %g@?.YxjT
buff.append("{"); 7
0?iZIK _
buff.append("count:").append(count); WnG2\(U
buff.append(",p:").append(p); qm$(_]R~`
buff.append(",nump:").append(num); $A?9U}V#^
buff.append(",results:").append ,jRAVt+{N
nsI+04[F
(results); Mw0>p5+ cy
buff.append("}"); *,JE[M
return buff.toString(); o#p%IGG`
} V~/G,3:0y%
VaD+:b4
} _CHzwNU
AtJ{d^
u79- B-YW^