Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K^z-G=|N
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 T{=.mW^ x
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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 SR>Sq2cW0
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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 mtDRF'>P:
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分页支持类: |F5^mpU
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java代码: _nu
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package com.javaeye.common.util; L'=e /&
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import java.util.List; ,Ie~zZE&
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publicclass PaginationSupport { fM8kS
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publicfinalstaticint PAGESIZE = 30; Yh/-6wg
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privateint pageSize = PAGESIZE; 4/D~H+k
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privateList items; Q"c!%`\
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privateint totalCount; L^PZ\OC
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privateint[] indexes = newint[0]; 9R.IYnq
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privateint startIndex = 0; wqo2iRql
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public PaginationSupport(List items, int Re?sopg0r
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totalCount){ =!NYvwg6;o
setPageSize(PAGESIZE); I%xrDiK97
setTotalCount(totalCount); }i_[wq{E&
setItems(items); lv9Ss-c4
setStartIndex(0); 'qLk"
} h`&@>uEiq
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public PaginationSupport(List items, int &rj6<b1A
&B3Eq1A
totalCount, int startIndex){ /:dVW"A|
setPageSize(PAGESIZE); Y.rHl4
setTotalCount(totalCount); (\FjbY9&
setItems(items); }|f\'S
setStartIndex(startIndex); :0ND0A{K:
} :j$K.3n
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public PaginationSupport(List items, int 1DcYc-k#
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totalCount, int pageSize, int startIndex){ ri~d Wx
setPageSize(pageSize); `9Ngax=_
setTotalCount(totalCount); mm%w0dOb"
setItems(items); G1B~?i2$ ?
setStartIndex(startIndex); G~)jk+Qq
} 'ntb.S)
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publicList getItems(){ H^"BK-`hs
return items; _%l+v
} 4,f[D9|:
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publicvoid setItems(List items){ [$?S9)Xd
this.items = items; Kbx (^f12
} Q3%a=ba)h
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publicint getPageSize(){ [$3Zid
return pageSize; IC[SJVH;
} !_<. 6ja
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; 'N=' B<^;%
} hX)r%v:
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publicint getTotalCount(){ fh$U"
return totalCount; En6fmEn&;o
} a[s%2>e
3]'=s>UO>^
publicvoid setTotalCount(int totalCount){ ni@D7:h
if(totalCount > 0){ v)N6ZOj*C
this.totalCount = totalCount; i#lvt#2J0
int count = totalCount / w ;H
wO}
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pageSize; c%pW'UE&
if(totalCount % pageSize > 0) CCq<y
count++; K1O/>dN_\O
indexes = newint[count]; oD{V_/pdx
for(int i = 0; i < count; i++){ A#1aO
indexes = pageSize * f]T1:N*t
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i; l@1f L%f
} sLbz@5 4
}else{ toTAWT D
this.totalCount = 0; /dOQ4VA\
} =i%2/kdi0b
} WbH/K]/1)h
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publicint[] getIndexes(){ pY =?r{@
return indexes; spO?5#
} o~P8=1t
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publicvoid setIndexes(int[] indexes){ 1:YDN.*
this.indexes = indexes; s>~&:GUwR
} w])~m1yW
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publicint getStartIndex(){ N_pJE?
return startIndex; q(.%f3(
} `H/HLCt
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publicvoid setStartIndex(int startIndex){ 6El%T]^
if(totalCount <= 0) =q
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this.startIndex = 0; e7#=F6
elseif(startIndex >= totalCount) qx0o,oZN!
this.startIndex = indexes -<z'f){gb
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[indexes.length - 1]; D{BH~IM
elseif(startIndex < 0) 4Hzbb#
this.startIndex = 0; ^D4 b\mF
else{ =Bo0Oei
this.startIndex = indexes SVq7qc9K?
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[startIndex / pageSize]; l'16B^
} =j;o,
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} /u:Sn=SPd
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publicint getNextIndex(){ K&|zWpb
int nextIndex = getStartIndex() + &<UOi@
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pageSize; RB &s$6A
if(nextIndex >= totalCount) ?!~au0
return getStartIndex(); =:"@YD^a4
else &u=FLp5
return nextIndex; mz\m^g3
} >MQW{^
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publicint getPreviousIndex(){ =?*V3e3{
int previousIndex = getStartIndex() - 3J,/bgL5
*c3o&-ke9
pageSize; 9 oq(5BG,
if(previousIndex < 0) cQ+,F2
return0; :He:Bdk
else /=r&9P@Ay<
return previousIndex; \17)=W
} n.1a1 Tf
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} _R-#I
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抽象业务类 H`io|~Q
java代码: fZ
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/** W\KZFrV@
* Created on 2005-7-12
@ics
*/ I"
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package com.javaeye.common.business; A,=l9hE'
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import java.io.Serializable; 3QR-8
import java.util.List; *v5y]E%aW
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import org.hibernate.Criteria; g)p[A 4
import org.hibernate.HibernateException; %##9.Xm6l
import org.hibernate.Session; 1^W Aps
import org.hibernate.criterion.DetachedCriteria; Bkz
import org.hibernate.criterion.Projections; JGdBpj:
import 9a4RW}S<
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org.springframework.orm.hibernate3.HibernateCallback; X|q0m3jt
import zYs? w=
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org.springframework.orm.hibernate3.support.HibernateDaoS jyT(LDsS
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upport; ePY K^D
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import com.javaeye.common.util.PaginationSupport; ,`Mlo
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public abstract class AbstractManager extends 0WPxzmY
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HibernateDaoSupport { 8'quQCx*=
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privateboolean cacheQueries = false; 6/n;u{|
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privateString queryCacheRegion; Ebk@x=E
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publicvoid setCacheQueries(boolean V\xQM;
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cacheQueries){ J *B`C^i
this.cacheQueries = cacheQueries; _Ey8P0-I
} W UV Q_<i+
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publicvoid setQueryCacheRegion(String i@;a%$5
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queryCacheRegion){ tvH)I px
this.queryCacheRegion = \G"/Myi
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queryCacheRegion; Zu hT \l
} tO0+~Wm
}hf*Jw
publicvoid save(finalObject entity){ =0-qBodbl
getHibernateTemplate().save(entity); H9Z3.F(2
} E:tUbWVp
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publicvoid persist(finalObject entity){ 8]L.E
getHibernateTemplate().save(entity); R.QcXz?d
} Eg:p_F*lr
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publicvoid update(finalObject entity){ 3k(?`4JJ
getHibernateTemplate().update(entity); S`^W#,rj
} 9c 6V&b
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publicvoid delete(finalObject entity){ pJ(l=a
getHibernateTemplate().delete(entity); 2u:j6ic
} Ue7W&N^E
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publicObject load(finalClass entity, aD^MoB3
@88 efF
finalSerializable id){ SM<kE<q#
return getHibernateTemplate().load CG7LF
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(entity, id); 93dotuF
} S.jjB
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publicObject get(finalClass entity, IY:O? M
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finalSerializable id){ 5a&wM
return getHibernateTemplate().get y{sA[ "
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(entity, id); R;yAqr29
} :6 fQE#(s&
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publicList findAll(finalClass entity){ *X #e
return getHibernateTemplate().find("from xRUYJ=|oh
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" + entity.getName()); ]4yvTP3[Rm
} O+$70
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publicList findByNamedQuery(finalString &1{k^>oz
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namedQuery){ ("6W.i>
return getHibernateTemplate H-W)Tq_?-
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().findByNamedQuery(namedQuery); 6Ts`5$e
} bM-Rj1#Lo
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publicList findByNamedQuery(finalString query, /z5lxS@#
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finalObject parameter){ m5pVt4
return getHibernateTemplate w-$w
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().findByNamedQuery(query, parameter); pYG,5+g
} :c t+.#
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publicList findByNamedQuery(finalString query, q9!9OcN2
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finalObject[] parameters){ A&F4;>dms
return getHibernateTemplate Y
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D3{lyi|8
().findByNamedQuery(query, parameters); Yn>zR I
} <^Tj}5)n
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publicList find(finalString query){ O| ]Ped9
return getHibernateTemplate().find W6T&hB
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(query); 6~ `bAe`}
} +df?N
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publicList find(finalString query, finalObject o3qv945
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parameter){ CE,Om^
return getHibernateTemplate().find @U{M"1zZe
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(query, parameter); JZzf,G:
} hH}/v0_ jb
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public PaginationSupport findPageByCriteria 6sl<Z=E#
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(final DetachedCriteria detachedCriteria){ lg>AWTW[
return findPageByCriteria j*4S] !
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Nh9!lB m*]
} ]ECZU
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public PaginationSupport findPageByCriteria %}XMhWn{
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(final DetachedCriteria detachedCriteria, finalint 8
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startIndex){ L0b]^_tI
return findPageByCriteria }27Vh0v
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(detachedCriteria, PaginationSupport.PAGESIZE, IGT_
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startIndex); ukf\*
} ]a#]3(o]}
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public PaginationSupport findPageByCriteria ~#_$?_/(
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(final DetachedCriteria detachedCriteria, finalint 5,BkwAr+6[
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pageSize, g/Jj]X#r
finalint startIndex){ cGta4;
return(PaginationSupport) IQ=|Kj9h
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getHibernateTemplate().execute(new HibernateCallback(){ "!6~*!]c
publicObject doInHibernate Y0O<]2yVx
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(Session session)throws HibernateException { ptyDv
Criteria criteria = H)T# R?
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detachedCriteria.getExecutableCriteria(session); BON""yIC
int totalCount = !9 LAXM
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((Integer) criteria.setProjection(Projections.rowCount %GCd?cFF
k`mrRs
()).uniqueResult()).intValue(); y'|W['
criteria.setProjection e=;@L3f
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(null); C%?D E@k
List items = {_ho!OS>
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criteria.setFirstResult(startIndex).setMaxResults
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(pageSize).list(); _AHB|P I
PaginationSupport ps = 3KFrVhB=
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new PaginationSupport(items, totalCount, pageSize, ajW$d!
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startIndex); t>GLZzO
return ps; 'a/6]%QFd!
} 7K]U|K#
}, true); D3AtYt
} < Gy!i/
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public List findAllByCriteria(final oy2dA
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DetachedCriteria detachedCriteria){ C+]q
return(List) getHibernateTemplate x*"pDI0k)
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().execute(new HibernateCallback(){ :mV7)oWH
publicObject doInHibernate _E<O+leWf
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(Session session)throws HibernateException { MN M>
Criteria criteria = b,
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detachedCriteria.getExecutableCriteria(session); [xs)u3b
return criteria.list(); Ta\8>\6
} HD8"=7zJk
}, true); grfdvN
} KYmWfM3^
aU]O$Pg{
public int getCountByCriteria(final p9 ,\ {Is
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DetachedCriteria detachedCriteria){ -anFt+f-
Integer count = (Integer) dYew7
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getHibernateTemplate().execute(new HibernateCallback(){ ?r'TH/>
publicObject doInHibernate (VXx G/E3
];{l$-$$
(Session session)throws HibernateException { Or#+E2%1E
Criteria criteria = #
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detachedCriteria.getExecutableCriteria(session); ic{.#R.BY
return &0
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criteria.setProjection(Projections.rowCount Up/u|A$0V
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()).uniqueResult(); W/ZahPPq
} V=zM5 MH2
}, true); -2jBs-z
return count.intValue(); )4F/T, {;m
} ]T3BDgu%&
} A]O5+"mc
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用户在web层构造查询条件detachedCriteria,和可选的 EO9kE.g
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Aiks>Cyi23
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PaginationSupport的实例ps。 ug6f
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ps.getItems()得到已分页好的结果集 <E7Vbb9*
ps.getIndexes()得到分页索引的数组 j
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ps.getTotalCount()得到总结果数 \`Ph=lJO
ps.getStartIndex()当前分页索引 6aF'^6+a
ps.getNextIndex()下一页索引 ! N"L`RWD
ps.getPreviousIndex()上一页索引 g"dZB2`C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ox\B3U%`p}
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 5Du>-.r
)*TW\v`B
一下代码重构了。 [`zbf_RyO
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我把原本我的做法也提供出来供大家讨论吧: v1"g!%U6
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首先,为了实现分页查询,我封装了一个Page类: 9?l?G GmQ
java代码: (4{ C7
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/*Created on 2005-4-14*/ f?>-yMR|
package org.flyware.util.page; =@1R ozt
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/** e0|_Z])D
* @author Joa UP~WP@0F
* 1hMX(N&|
*/ =~W0 ~lxX
publicclass Page { )S wG+k,
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/** imply if the page has previous page */ uku}Mr"p
privateboolean hasPrePage; lEyG9Xvi
kuTq8p2E
/** imply if the page has next page */ Oj4u!SY\j
privateboolean hasNextPage; Dc&9emKI
_r<zSH%
/** the number of every page */ _,Rsl$Tk'
privateint everyPage; -e`oW.+
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/** the total page number */ bU:}ZO^S
privateint totalPage; z3vsz
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/** the number of current page */ )4'x7Qg/
privateint currentPage; ~3'OiIw1@
dxkRk#mf:
/** the begin index of the records by the current e$ XY\{
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query */ ;Oi[:Ck
privateint beginIndex; \&\_>X.,
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/** The default constructor */ _\4`
public Page(){ c9*1$~(v0I
?x5wS$^q<
} XoKO2<3
)DGz`->
/** construct the page by everyPage k"q!|+&Fs
* @param everyPage E,<\T6/%q
* */ eC+"mhB
public Page(int everyPage){ jsNH`"
this.everyPage = everyPage; =.qm8+
} 9k=U0]!ch
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/** The whole constructor */ I9[1U
public Page(boolean hasPrePage, boolean hasNextPage, kb"_6,[Ms
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int everyPage, int totalPage, }XGMa?WR
int currentPage, int beginIndex){ Z{,GZT
this.hasPrePage = hasPrePage; 3wN?|N
this.hasNextPage = hasNextPage; Yo~LckFF
this.everyPage = everyPage; 2qs>Bshf
this.totalPage = totalPage; VxkCK02k
this.currentPage = currentPage; ZR;8rZ](
this.beginIndex = beginIndex; eKZ@FEZ
} C%}]"0Q1
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/** %Ycx C0S[
* @return kf%&d}2to
* Returns the beginIndex. A9\]3 LY
*/ 7SgweZ}"
publicint getBeginIndex(){ b 0LGH.
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return beginIndex; DU5:+"
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} aN^]bs?R
3I9T|wQ-]
/** PGPISrf
* @param beginIndex 8)^B32
* The beginIndex to set. f7XQ~b
*/ h4hN1<ky\
publicvoid setBeginIndex(int beginIndex){ S=0"f}Jo.
this.beginIndex = beginIndex; prNhn:j
} IVI~1~
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/** Zg
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* @return &8[ZN$Xe"
* Returns the currentPage. YCa@R!M*O
*/ *4<4
publicint getCurrentPage(){ s?QVX~S"
return currentPage; ~Cjz29|gp
} tigT@!`$Y
s kN9O"^A
/** -PNi^
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* @param currentPage Q~Ay8L+
* The currentPage to set. v,/[&ASz
*/ 3lo;^KX !
publicvoid setCurrentPage(int currentPage){ 2\^G['9
this.currentPage = currentPage; @Ii-NmOr
} HXQ e\r
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/** Tbv/wJ
* @return ShQ|{P9
* Returns the everyPage. ]dvPx^`d{
*/ ,i?)
publicint getEveryPage(){ #SKfE
return everyPage; \HAJ\9*w)
} sX+`wc
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/** q@(1Yivk
* @param everyPage zVSx$6eiU
* The everyPage to set. f}^I=pS&
*/ \+-zRR0
publicvoid setEveryPage(int everyPage){ +' %@!
this.everyPage = everyPage; bS>R5*Zp
} HF"Eys
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/** 6+.>5e
* @return a:85L!~:l
* Returns the hasNextPage. *HR+a#o
*/ m#tpbFAsc
publicboolean getHasNextPage(){ >lrhHU
return hasNextPage; 8zY)J #
} .*BA 1sjE
#~L!pKM
/** 5sCFzo<=vh
* @param hasNextPage ;HDZ+B
* The hasNextPage to set. S}[l*7
*/ Kx~$Bor_!
publicvoid setHasNextPage(boolean hasNextPage){ ZWO)tVw9G
this.hasNextPage = hasNextPage; ; e@gO
} ipobr7G.SD
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/** 8".2)W4*
* @return LheFQ A
* Returns the hasPrePage. $.pTB(tO
*/ NmJ`?-Z
publicboolean getHasPrePage(){ OTj,O77k
return hasPrePage; ._?V%/
} %SAw;ZtQ:
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@
/** ;j{7!GeKa
* @param hasPrePage lwc5S`"
* The hasPrePage to set. we3tx{j
*/ hq=,Z1J
publicvoid setHasPrePage(boolean hasPrePage){ # ly@;!M
this.hasPrePage = hasPrePage; OF[?Z
} &iNwvA%9D
gV8"VZg2
/** hoenQ6N^:
* @return Returns the totalPage. XVt/qb%)r
* e+. \pe\
*/ l4rMk^>>
publicint getTotalPage(){ ~2@Lx3t$
return totalPage; (9 sIA*,}
} jNA1O68N
|~WYEh
/** UUeB;'E+
* @param totalPage fiVHRSX60
* The totalPage to set. jfD1
*/ WK0C
publicvoid setTotalPage(int totalPage){ !SO8O
this.totalPage = totalPage; `
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} WF2NG;f=
rAb&I"\ZY
} >O#grDXb
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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 *FK`&(B+}
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个PageUtil,负责对Page对象进行构造: j(eFoZz,
java代码: P`S@n/}
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/*Created on 2005-4-14*/ WkP
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package org.flyware.util.page; "7,FXTaer
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import org.apache.commons.logging.Log; pu+ur=5&
import org.apache.commons.logging.LogFactory; Zp&@h-%YoD
9XLFHV("
/** s
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* @author Joa #]E(N~
* ujr(K=E
*/ C$d>_r
publicclass PageUtil { t{dSX?<nt
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privatestaticfinal Log logger = LogFactory.getLog }fZ`IOf
h5"Ov,K3[
(PageUtil.class); ibpzeuUl
@?kM'*mrZM
/** oH#v6{y
* Use the origin page to create a new page D\1k.tI
* @param page >\2:\wI
* @param totalRecords kL>d"w
* @return @F~LW6K
*/ ^e Gue
publicstatic Page createPage(Page page, int jZpa0g rA
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totalRecords){ +9XQ[57
return createPage(page.getEveryPage(), :7g=b%;
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page.getCurrentPage(), totalRecords); WC,+Cn e
}
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/** 17|np2~
* the basic page utils not including exception amWD-0V
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handler ?4 S+edX
* @param everyPage #]]Su91BA
* @param currentPage ]y@F8$D!
* @param totalRecords &fOdlQ?
* @return page e:w&(is
*/ F_;DN:
{
publicstatic Page createPage(int everyPage, int l[GOs&D1
jS.g]k
currentPage, int totalRecords){
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everyPage = getEveryPage(everyPage); a4MZ;5
currentPage = getCurrentPage(currentPage); 0aI;\D*Ts
int beginIndex = getBeginIndex(everyPage, /)
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IA&L]
currentPage); @n&<B`/
int totalPage = getTotalPage(everyPage, ])DX%$f
CO:u1?
totalRecords); 2@=IT0[E\
boolean hasNextPage = hasNextPage(currentPage, j;1 -p>z
hm*cw[#O1x
totalPage); 1oLv.L
boolean hasPrePage = hasPrePage(currentPage); D*PYr{z'
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returnnew Page(hasPrePage, hasNextPage, errH>D~
everyPage, totalPage, *?ITns W<
currentPage, Ih}1%Jq
p d[ncL
beginIndex); LQYy;<K
} uX/$CM
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privatestaticint getEveryPage(int everyPage){ v``-F(i$
return everyPage == 0 ? 10 : everyPage; )E#2J$TD
} =sJ
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[,RI-#n
privatestaticint getCurrentPage(int currentPage){ 3REx45M2
return currentPage == 0 ? 1 : currentPage; lbdTQ6R
} H9)m^*
"syh=BC
v
privatestaticint getBeginIndex(int everyPage, int p?D2)(
<*!i$(gn
currentPage){ U9y|>P\)T
return(currentPage - 1) * everyPage; JA)?p{j
} X~=xXN.
ltB.Q
privatestaticint getTotalPage(int everyPage, int uMb>xxf
WEg6Kz
totalRecords){ m([(:.X/IX
int totalPage = 0; $rF=_D6
eN?Y7
if(totalRecords % everyPage == 0) TL$EV>Nr
totalPage = totalRecords / everyPage; D4Al3fe
else OO dSKf8
totalPage = totalRecords / everyPage + 1 ; J_;N:7'p
9^"b*&>P
return totalPage; g"s$}5{8:
} ,#FLM`
/MMd`VrC2
privatestaticboolean hasPrePage(int currentPage){ \0l>q ,
return currentPage == 1 ? false : true; PNF?;*`-{7
} SzwQOs*
W7"{r)7
privatestaticboolean hasNextPage(int currentPage, {rfF'@[
A1)wo^,
int totalPage){ YJg,B\z}
return currentPage == totalPage || totalPage == 0~wF3BgV
9SlNq05G7
0 ? false : true; w=]Ks'C]
} %W,D;?lEo>
X"gCRn%tn
A[IL
H_w
} NjPDX>R\K
1g##sSa6
b`yZ|j'ikd
SK1!thQy
>3 yk#U|7}
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 MV_Srz
dY?`f<*
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ETp%s{8
y@2epY?{
做法如下: H>9CW<8
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^ -FX
yR{x}DbG
的信息,和一个结果集List: b" xmqWa
java代码: CT0l!J~5m~
C%*k.$#r!
Mb3}7 @/[
/*Created on 2005-6-13*/ Om{l>24i.\
package com.adt.bo; k#[F`
(b?{xf'G
import java.util.List; +3s%E{
M(#m0xB
import org.flyware.util.page.Page; u2oKH{/z
3lV^B[$
/** Pe C7
* @author Joa <YA&Dr3OD
*/ D7Y)?Z5A;
publicclass Result { ?USQlnr:R/
G}
eUL|S
private Page page; 8WE{5#oi
1/p*tZP8i
private List content; {G <kA(Lm
syU9O&<
/** y/e2l
* The default constructor dz~co Z9
*/ vR0];{
public Result(){ cvwhSdZu8
super(); e8YMX&0%
} m<L;
rc+C?)S
/** =rdY
@
* The constructor using fields 1&fc1uYB4
* %m:m}ziLQ
* @param page zlR?,h-[3
* @param content I^o!n5VM
*/ |ZodlYF
public Result(Page page, List content){ JS}{ %(B
this.page = page; XLMb=T~S
this.content = content; s1|/S\
} q+B&orp
!`!| Zw
/** *6xgctk
* @return Returns the content. cA6lge<{~
*/ XeBP`\>Ve
publicList getContent(){ .>z][2oz
return content; eIl]oC7*
} xBu1Ak8w
5[j`6l
/** T~h5B(J;
* @return Returns the page. "c}@V*cO<d
*/ 5*[2yKsTi
public Page getPage(){ 7ugZE93!
return page; O;7)Hjw t
} f|u#2!7
qj cp65^
/** ]%Zz \Q
* @param content NEa>\K<\
* The content to set. r>bJ%M}
*/ N'xSG`,Mg
public void setContent(List content){ (E]!Z vE
this.content = content; EyY.KxCB
} @
49nJi
VLBE'3Qg1
/** 5k|9gICyd*
* @param page DcSnia62f
* The page to set. s+:=I
e
*/ Q f(p~a(d
publicvoid setPage(Page page){ =@F&o4) r
this.page = page; \M'-O YH_[
} )Ud-}* g
} L@JOGCYy
+H$!a
=IAsH85Q
0ZQ' _g|%
ccd8O{G.M
2. 编写业务逻辑接口,并实现它(UserManager, 1:Si,d,wh
l }XU59
UserManagerImpl) Z$J#|
java代码: dL|+d:v
jY_T/233d
@29U@T
/*Created on 2005-7-15*/ |d6T/Uxo
package com.adt.service; :_M;E"9R
BB|?1"neg
import net.sf.hibernate.HibernateException; #p[',$cC
4Vq%N
import org.flyware.util.page.Page; \@&_>us
:x_'i_w
import com.adt.bo.Result; C*nB
}MUn/ [x
/** gk`zA
* @author Joa J*9$;
*/ bTQNb!&
publicinterface UserManager { Ytgj|@jsp
aZbw]0q@o
public Result listUser(Page page)throws pKi& [
Rb3V^;i
HibernateException; -.{g}R%
G\TfL^A
} ^]
kF{
o?
sUPz/Z.h
@?"h
!fyu
!Ra*)b"
=~p>`nV
java代码: -\#0]F:-
_ 84ut
XV^1tX>f{
/*Created on 2005-7-15*/ Hty0qr3
package com.adt.service.impl; " LJq%E
XkyKBg-
import java.util.List; |r bWYl.b
{/pm<k=
import net.sf.hibernate.HibernateException; ;NRF=d>
vB+ '
import org.flyware.util.page.Page; Zdn~`Q{
import org.flyware.util.page.PageUtil; "1,pHR-+R
0T46sm r
import com.adt.bo.Result; H*9~yT'Q
import com.adt.dao.UserDAO; @Vu(XG
import com.adt.exception.ObjectNotFoundException; ~H!S,"n^,P
import com.adt.service.UserManager; "*})3['n
rb{P :MX
/** &5:tn=E
* @author Joa B-l'vVx
*/ Uk\Id~xLV
publicclass UserManagerImpl implements UserManager { H<1WbM:w
6S~sVUL9`
private UserDAO userDAO; V%Sy"IG
VU@9@%TN
/** _SA5e3#
* @param userDAO The userDAO to set. cp o-.
*/ U)3DQ6T99
publicvoid setUserDAO(UserDAO userDAO){ MMj9{ou
this.userDAO = userDAO; ,*7d
} -ig6w.%lk
$HJwb-I
/* (non-Javadoc) R"K#7{p9
* @see com.adt.service.UserManager#listUser GaSPJt
wg w(YU
(org.flyware.util.page.Page) 'R_g">B.
*/ 4Fm90O
public Result listUser(Page page)throws NB<A>baL*
u,6~qQczE
HibernateException, ObjectNotFoundException { }3?n~s\)6f
int totalRecords = userDAO.getUserCount(); +a*tO@HG
if(totalRecords == 0) \G-KplKS
throw new ObjectNotFoundException &~W:xg(jN
J(6oL
("userNotExist"); ?Ae ven
page = PageUtil.createPage(page, totalRecords); 4rrSb*
List users = userDAO.getUserByPage(page); ;amXY@RmH
returnnew Result(page, users); w}=5ElB
} &iV,W4
F8apH{&t
} 50={%R
|DsnNk0c
8Ac:_Zg
sM9+dh
^`G}gWBx}w
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 @9"J|}
y:6; LZ9[
询,接下来编写UserDAO的代码: _8E/)M
3. UserDAO 和 UserDAOImpl: ]9@F~)
java代码: z^<"x|:
=W'Ae,&
!50[z:
/*Created on 2005-7-15*/ & \f{E\A#
package com.adt.dao; $*?,#ta
)6aAB|
import java.util.List; uS^Ipxe\
yeMB0Z*r
import org.flyware.util.page.Page; ZMq6/G*fD
Ih"XV
import net.sf.hibernate.HibernateException; cCxBzkH6
p3^m9J
/** ^f(@gS}?
* @author Joa V 0rZz
*/ }I>tO9M
publicinterface UserDAO extends BaseDAO { 5D'\b}*lJ}
[W7CXZDd
publicList getUserByName(String name)throws d m`E!R_
:eCU/BC4
HibernateException; y~\oTJb
-(=eM3o-9m
publicint getUserCount()throws HibernateException; }B1!gz$YNO
hyFyP\u]
publicList getUserByPage(Page page)throws j?+X\PtQ
?[lV-
HibernateException; hzvd t
`V04\05
} >m$ 1+30X
)h)]SF}
ZEx}$<)_
Ll4g[8
5bgs*.s
java代码: 9_5ow
|/)${*a4n
:n-]>Q>5=k
/*Created on 2005-7-15*/ s']Bx=
package com.adt.dao.impl; l~$+,U&XNe
IqoR7ajA
import java.util.List; 5wDg'X]>V
&:`U&06q
import org.flyware.util.page.Page; (P:<t6;+
#n8IZ3+
import net.sf.hibernate.HibernateException; RtM8yar+sn
import net.sf.hibernate.Query; w {3<{
K>@+m
import com.adt.dao.UserDAO; A nX%[W "
|mw.qI|
/** =UfsL%
* @author Joa XSyHk"g`
*/ |0f>aZ
public class UserDAOImpl extends BaseDAOHibernateImpl r<d_[?1N
jIyB
implements UserDAO { gK'1ZLdZ2
OD!& .%
/* (non-Javadoc) <d$x.in
* @see com.adt.dao.UserDAO#getUserByName XcUwr
ybKWOp:O
(java.lang.String) lE(a%'36
*/ W~7A+=&
publicList getUserByName(String name)throws ",KCCis
$cU!m(SILQ
HibernateException { $arK(
String querySentence = "FROM user in class |M,iM]
QvKh,rBFVG
com.adt.po.User WHERE user.name=:name"; 7V!*NBsl
Query query = getSession().createQuery gq'Y!BBQy
#ZrHsfP
(querySentence); ) iN/ua
query.setParameter("name", name); >E{";C)
return query.list(); Tq[kl'_
} 4p,EBn9(
Evg_q>
/* (non-Javadoc) Eu@huN*/
* @see com.adt.dao.UserDAO#getUserCount() Oagsoik
*/ t^G"f;Ra+
publicint getUserCount()throws HibernateException { cmU1!2.1E
int count = 0; 1oWED*B
String querySentence = "SELECT count(*) FROM ?Yth0O6?sb
Ku}Z
user in class com.adt.po.User"; ^<a
t'jk6
Query query = getSession().createQuery kr9*,E9cv
n|R J;d30Q
(querySentence); ORJIo
count = ((Integer)query.iterate().next mQ|v26R
9CWezI+
()).intValue(); )9"_J9G
return count; r\-uJ~8N
} b((M)Gz
{CGUL|y
/* (non-Javadoc) @v)p<r^M">
* @see com.adt.dao.UserDAO#getUserByPage :2rZcoNb.
8"8t-E#?
(org.flyware.util.page.Page) b)qoh^
*/ Ch|jtVeuyJ
publicList getUserByPage(Page page)throws ':3pq2{
{YAJBIvHV
HibernateException { jN;@=COi
String querySentence = "FROM user in class lJ}_G>GJ
DpvI[r//'*
com.adt.po.User"; L(|N[#
Query query = getSession().createQuery 1Vrh4g.l
2q=AEv/
(querySentence); PGhY>$q>b
query.setFirstResult(page.getBeginIndex()) ~5%W:qwQ
.setMaxResults(page.getEveryPage()); xqG[~)~
return query.list(); $!-c-0ub
} 2a`o
&S
rrBsb -
} xSsa(b
--HZX
$0>60<J
F@'Jbd`
KWowN;
至此,一个完整的分页程序完成。前台的只需要调用 /_AnP
i1NY9br
userManager.listUser(page)即可得到一个Page对象和结果集对象 4U+xb>
{GK;63`1
的综合体,而传入的参数page对象则可以由前台传入,如果用 =hC,@R>;
-pf}
webwork,甚至可以直接在配置文件中指定。 5
ZGNz1)?V
+./H6!
下面给出一个webwork调用示例: e,vvzso
java代码: 1PQ~jfGi
nYR#
bpJ(XN}E
/*Created on 2005-6-17*/ ;g5m0l5
package com.adt.action.user;
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4:$4u@
import java.util.List; QwJVS(Gs4
Pq;U&,
import org.apache.commons.logging.Log; )wam8k5
import org.apache.commons.logging.LogFactory; &:9cAIe]H
import org.flyware.util.page.Page; "d#Y}@*~o
lT(WD}OS
import com.adt.bo.Result; 4o
<Uy
import com.adt.service.UserService; u~7hWiY<2
import com.opensymphony.xwork.Action; :dl]h&C^
I7 |Pi[e
/** )t0$qd ]
* @author Joa Vd,jlt.t
*/ ([\
publicclass ListUser implementsAction{ QdH\LL^8R4
V:In>u$QJ!
privatestaticfinal Log logger = LogFactory.getLog =9'RM>
9YIM'q>`v
(ListUser.class); :~e>Ob[,"
Neq+16*u
private UserService userService; D/Z6C&/I
]HKQDc'
private Page page; fHE<(
m4hX 'F
privateList users; E4`N-3
ieDk ;
/* \r;#g{
_
* (non-Javadoc) Vwg|K|
* h58`XH
* @see com.opensymphony.xwork.Action#execute() Zd^rNHhA
*/ ,&]S(|2%>t
publicString execute()throwsException{ H*RC@O_hv
Result result = userService.listUser(page); 0%9 q8M;
page = result.getPage(); >Wm`v.-
users = result.getContent(); q8X feoUV
return SUCCESS; ]fx"4qKM
} c]x1HvPE
jSD#X3qp
/** aktU$Wbwl
* @return Returns the page. [-65PC4aN
*/ 1-%fo~!l
public Page getPage(){ a,@]8 r-"
return page; >:A ARx%
}
?]|\4]zV
/ ;$#d}R
/** {C 6=[
* @return Returns the users. J`peX0Stl
*/ 63q^ $I
publicList getUsers(){ ]e"=$2d$
return users; 3EV;LH L
} k$R~R-'
~Sg5:T3
/** b*;Si7-
* @param page 9oyE$S h]
* The page to set. y?[ v=j*U
*/ Pu7_
v
publicvoid setPage(Page page){ ]{)a,c NG
this.page = page; aGrIQq/k)%
} 9=vMgW
;kFDMuuO
/** *;l]8.
* @param users H7z,j}l
* The users to set. !POl;%\
*/ Buf/@B7+\
publicvoid setUsers(List users){ RY]#<9>M
this.users = users; 4^p5&5F
} JmF l|n/H
F |d\k Q
/** +DW~BS3
* @param userService j-4VB_N@
* The userService to set. nGpXI\K
*/ T}Km?d
publicvoid setUserService(UserService userService){ X\]L=>]C
this.userService = userService; _D+}q_
} )#BMTKA^
} %7"q"A r[
_BM"
]t*
nG,A@/N
49rf7NT-g
$Z!`Hb
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, ~qcNEl\-y
NaPt"G
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
;9[fonk
bV(Y`g
么只需要: ujDd1Bxf?
java代码: C\S3Gs
@E;=*9ek{u
4iqoR$3Fc
<?xml version="1.0"?> LIS)(X<]?
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork &R[ Mc-2
-d~4A
1.0//EN" "http://www.opensymphony.com/xwork/xwork- FK:;e
lZ
8e*,jH3
1.0.dtd"> @XgKYm
w zYzug
<xwork> un)4eo!7
%j:]^vqFA
<package name="user" extends="webwork- X>d"]GD
Q;[,Q~c[u
interceptors"> `e(c^ z#
O,J>/
<!-- The default interceptor stack name 8J=?5
.Obw|V-
--> vX{J' H]u
<default-interceptor-ref $&y%=-] |
T?:Rdo!:u
name="myDefaultWebStack"/> $h5xH9x
;
M=%l}FSTw(
<action name="listUser" a;rdQ>
@>d*H75
class="com.adt.action.user.ListUser"> W0y '5`
<param JI? rL
I, -hf=-
name="page.everyPage">10</param> VLS0XKI)
<result DQNnNsP:M-
3
*d"B tg
name="success">/user/user_list.jsp</result> &%8'8,.
</action> ~"!]
3C,L
AuUde$l_
</package> Y,GU%[+
D!Q">6_"z
</xwork> ;o^eC!:/%
$56Z#'(D
V_C-P[2~
AjmVc])
,`wXg
us;YV<)d
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 y)F;zW<+
9:fOYT$8
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 B.wYHNNV
*meZ8DV2DH
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 c;%_EN%
O?NeSx1
S\''e`Eb"5
8MK>)P o)
q`|LRz&al
我写的一个用于分页的类,用了泛型了,hoho x9$` W
_.>QEh5"5
java代码: 3t`P@nL0;
3 ,>0a
pwO>h>ik
package com.intokr.util; $.C=H[QC
:@kGAI
import java.util.List; {_b%/eR1
^g*pGrl#
/** 4oK?-|=?
* 用于分页的类<br> .clP#r{U
* 可以用于传递查询的结果也可以用于传送查询的参数<br> guX
9}
* g+DzscIT
* @version 0.01 _6_IP0;
* @author cheng T#M,~lD
*/ p%iGc<vHX
public class Paginator<E> { 3Dg,GaRk
privateint count = 0; // 总记录数 WzAb|&?
privateint p = 1; // 页编号 #OBJzf*p
privateint num = 20; // 每页的记录数 6S\C}U/
privateList<E> results = null; // 结果 >C7r:%
flk=>h|
/** rJPb 3F
* 结果总数 K2he4<
*/ U3 */v4/
publicint getCount(){ @*}D$}aR'V
return count; CJ(NgYC h
} '/`= R
s<*XNNE7
publicvoid setCount(int count){ 0F@"b{&0
this.count = count; EM]s/LD@%
} Acnl^x7Y1
e.]K L('
/** i7]4W
* 本结果所在的页码,从1开始 t/ +=|*
* e@c0WlWa
* @return Returns the pageNo. \x)n>{3C
*/ :Mb%A
publicint getP(){ MA;1;uI,
return p; U2{ dN>
} h lkn%
W;_nK4$%'
/** A{UULVp
* if(p<=0) p=1 Z&0'a
* OTC!wI
g
* @param p %T X@I$Ba
*/ +hn+K1
publicvoid setP(int p){ xB_!>SqF1U
if(p <= 0) JXCCTUO
p = 1; ~3WM5 fv
this.p = p; 7#@cz5Su
} r~N"ere26
)A!>=2M`
/** (EK"V';
* 每页记录数量 ZaeqOVp/j
*/ *_R]*o!W'
publicint getNum(){ T;@;R%
return num; ,$1eFgY%
} WtViW=j'
RMd[Yr2e
/** ~GTz:nC*
* if(num<1) num=1 u @~JiiC%
*/ n9@ of
publicvoid setNum(int num){ #Xhdn\7
if(num < 1) P/xKnm~
num = 1; R16'?,
this.num = num; $wmvKQc{lx
} uIcn{RZ_z
A'G66ei
/** dlJbI}-v=
* 获得总页数 ) _mr! z(S
*/ @Gx.q&H
publicint getPageNum(){ K)qF+Vb^j
return(count - 1) / num + 1; m<{<s T
} S>.SSXlM
Q@
2i~Qo[
/** (Q%'N3gk
* 获得本页的开始编号,为 (p-1)*num+1 V+Cwzc^j
*/ /DQc&.jK
publicint getStart(){ M%1}/!J3
return(p - 1) * num + 1; dYSr4pb
} \cC%!4
I?"q/Ub~h
/** _cy2z
* @return Returns the results. ,Vh.T&X5
*/ bA\<.d
publicList<E> getResults(){ ZQ)>s>-
return results; Yu?95qk tP
} <,3^|$c%
Swp;HW7x
public void setResults(List<E> results){ |AcRIq
this.results = results; fRy^Q_~,
} ]4h92\\965
SV:4GVf
public String toString(){ HHq_P/'
StringBuilder buff = new StringBuilder r) $+
(4'$y`Z
(); P`#Z9 HM4
buff.append("{"); rFaF
Bd
buff.append("count:").append(count); 9so6WIWc
buff.append(",p:").append(p); }
@K FB
buff.append(",nump:").append(num); hF@Gn/
buff.append(",results:").append pX&pLaF
Ggl~nxz
(results); ,Y|^^?'j
Q
buff.append("}"); bx]N>k J
return buff.toString(); }b=}uiR#
} :T]o)
xEf'Bmebk
} S/Fkw4%
2>86oP&
mjWU0Gh%*