Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 UA/Q3)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (;P)oB"`C
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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 :U)q(.53
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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 {S(?E_id5b
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分页支持类: ej>8$^y
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java代码: 6+BR5Nr
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package com.javaeye.common.util; rA&|!1q"B
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import java.util.List; aB"W6[
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publicclass PaginationSupport { MBRRzq%F
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publicfinalstaticint PAGESIZE = 30; "0 \U>h
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privateint pageSize = PAGESIZE; &Eg>[gAIlp
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privateList items; ~"!F&
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privateint totalCount; 0[TZ$<v"
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privateint[] indexes = newint[0]; Cq;t;qN,nQ
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privateint startIndex = 0; GM|gm-t<@
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public PaginationSupport(List items, int 5:E7nqsNhq
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totalCount){ AJ` b-$Q
setPageSize(PAGESIZE); HS.3PE0^C
setTotalCount(totalCount); LF* 7;a
setItems(items); Kf2*|ZHj
setStartIndex(0); dQ@e+u5
} Dg%zN i2GS
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public PaginationSupport(List items, int Kc_QxON4
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totalCount, int startIndex){ (o)nN8
setPageSize(PAGESIZE); .]0B=w* Z
setTotalCount(totalCount); /Z HuT=j1
setItems(items); l;}D| 6+_W
setStartIndex(startIndex); )VQ:L:1t(
} ==`K$rM
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public PaginationSupport(List items, int ;!DUN zl
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totalCount, int pageSize, int startIndex){ q0{KYWOvk
setPageSize(pageSize); J!O5`k*.C
setTotalCount(totalCount); v' .:?9
setItems(items); \ F#mwl,>"
setStartIndex(startIndex); Q\&FuU
} =_I2ek
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publicList getItems(){ ^-cj=on=Q
return items; hNmC(saMGm
} #P=rP=
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publicvoid setItems(List items){ R8P7JY[h
this.items = items; &G7JGar
} C%t~?jEK~^
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publicint getPageSize(){ YlwCl4hq
return pageSize; |`_qmk[:R
} ?Q[uIQ?dV
//]g78]=O
publicvoid setPageSize(int pageSize){ {ER!
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this.pageSize = pageSize; SY>i@s+ML
} 4]A2Jl
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publicint getTotalCount(){ /c'3I
return totalCount; )Q9m,/F
} _Sy-&}c+
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publicvoid setTotalCount(int totalCount){ m]}
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if(totalCount > 0){ Or=
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this.totalCount = totalCount; \~d|MP}"F:
int count = totalCount / @'j=oTT
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pageSize; )n}Wb+2I
if(totalCount % pageSize > 0) A\iDK10Q$
count++; kLQPa[u4
indexes = newint[count]; vpcx 1t<
for(int i = 0; i < count; i++){ rM#jxAb
indexes = pageSize * K@Q_q/(%;
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} T`7;Rl'Q
}else{ /~NsHStn
this.totalCount = 0; i`)bn1Xm
} eU'DQp*
} (g
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publicint[] getIndexes(){ zJWBovT/
return indexes; 0'*whhH
} zQM3n =y
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publicvoid setIndexes(int[] indexes){ $,4;_4t
this.indexes = indexes; 5n!
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} 3US}('
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publicint getStartIndex(){ \?7)oFNz
return startIndex; 0H,1"~,w]
} LHU^%;L
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publicvoid setStartIndex(int startIndex){ |ybW
if(totalCount <= 0) n#t{3qzpD
this.startIndex = 0; .ii9-+_
elseif(startIndex >= totalCount) [~9rp]<
this.startIndex = indexes '#gd19#
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[indexes.length - 1]; jOj`S%7
elseif(startIndex < 0) 7yo/sb9h
this.startIndex = 0; X5 UcemO
else{ l:mC'aR
this.startIndex = indexes PhW<)B]
3IQ)%EN
[startIndex / pageSize]; <-62m8N|
} &54fFyJF
} w|:UTJ>@
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publicint getNextIndex(){ S%gb1's
int nextIndex = getStartIndex() + RpPbjz~
.|
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pageSize; BTjfzfO"
if(nextIndex >= totalCount) <
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return getStartIndex(); [` ~YPUR*
else 0&T0Ls#4
return nextIndex; 2-5AKm@K
} fH~InDT^
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publicint getPreviousIndex(){ . [DCL
int previousIndex = getStartIndex() - /3->TS
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pageSize; $~vy,^
if(previousIndex < 0) im{'PgiR
return0; ON#\W>MK?
else Ry>c]\a]
return previousIndex; =<w6yeko
} d!kiWmw,
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} q(<#7spz
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抽象业务类 )w];eF0c
java代码: 6z
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/** H?98^y7
* Created on 2005-7-12 +shT}$cb1
*/ ;@p2s'(
package com.javaeye.common.business; OrP-+eg
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import java.io.Serializable; #k2&2W=x
import java.util.List; a$ a+3}\
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import org.hibernate.Criteria; 7uG@hL36
import org.hibernate.HibernateException; ` W$
import org.hibernate.Session; $O" S*)9
import org.hibernate.criterion.DetachedCriteria; ModwJ
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import org.hibernate.criterion.Projections; c#sPM!!
import u4TU"r("A
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org.springframework.orm.hibernate3.HibernateCallback; Nf8."EDUW
import YSwAu,$jf
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org.springframework.orm.hibernate3.support.HibernateDaoS 1~:7W
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upport; jv7-i'I@
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import com.javaeye.common.util.PaginationSupport; hZ|*=/3k
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public abstract class AbstractManager extends d%_v
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HibernateDaoSupport { pOP`n3m0
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privateboolean cacheQueries = false; gX<"-,5jc
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privateString queryCacheRegion; ?8[,0l:|
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publicvoid setCacheQueries(boolean jqq96hP,
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cacheQueries){ YW55iyM
this.cacheQueries = cacheQueries; lJ.:5$2H
} ETvn$ Jdp
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publicvoid setQueryCacheRegion(String vmdu9"H
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queryCacheRegion){ "?EoYF_
this.queryCacheRegion = i? 5jl&30
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queryCacheRegion; +F3@-A
} (t'hWS
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publicvoid save(finalObject entity){ JU+Uzp
getHibernateTemplate().save(entity); #<df!)
} {^>dQ+S x7
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); K{)N:|y%!$
} 1}+lL)-!
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publicvoid update(finalObject entity){ {~NiGHY
getHibernateTemplate().update(entity); @wO"?w(
} rlG&wX
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publicvoid delete(finalObject entity){ 7U68|\fI!
getHibernateTemplate().delete(entity); Nd!0\ "AE
} 4_qd5K+n"
; (I(TG
publicObject load(finalClass entity, Ut:>'TwG
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finalSerializable id){ 4i0~t~vDpr
return getHibernateTemplate().load =" Q5Z6W
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(entity, id); fwaq
} !f5I.r~
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publicObject get(finalClass entity, R2{ y1b$l
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finalSerializable id){ F<SMU4]YdG
return getHibernateTemplate().get ERcj$ [:T(
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(entity, id); >7%Gd-;l
} CVfQ
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publicList findAll(finalClass entity){ d*3;6ZLy
return getHibernateTemplate().find("from N&g9z{m7
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" + entity.getName()); } :U'aa
} eytd@-7uX
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publicList findByNamedQuery(finalString H9'Y` -r
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namedQuery){ _ dFZR
return getHibernateTemplate o&45y&
7"}<J7"})
().findByNamedQuery(namedQuery); +~~FfIzf#
} HPl'u'.Hg
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publicList findByNamedQuery(finalString query, Jlgo@?Lc
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finalObject parameter){ cHN
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return getHibernateTemplate c(Liwuj
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().findByNamedQuery(query, parameter); u&MlWKCi
} Fy1@B(V%
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publicList findByNamedQuery(finalString query, bvdAOvxChW
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finalObject[] parameters){ .b'o}DLa
return getHibernateTemplate ygt7;};!
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().findByNamedQuery(query, parameters); 9WN4eC$
} p.{9OrH(4
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publicList find(finalString query){ W 2/`O?
return getHibernateTemplate().find ybWb'+x
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(query); Fkgnc{NI
} xWkCP2$?P
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publicList find(finalString query, finalObject JkT, i_
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parameter){ [I/f(GK
return getHibernateTemplate().find 4`Com~`6"
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(query, parameter); Y1e>P
} !uaV6K
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public PaginationSupport findPageByCriteria k.Tu#7
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(final DetachedCriteria detachedCriteria){ Yphru"\$
return findPageByCriteria 1rs`|iX5
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?^TjG)e7
} 7WZ).,qxY
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public PaginationSupport findPageByCriteria E,"?RbG
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(final DetachedCriteria detachedCriteria, finalint #H]cb#
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startIndex){ SQ*dC
return findPageByCriteria AhjK*nJF
7.hgne'<
(detachedCriteria, PaginationSupport.PAGESIZE, /?<tjK' "H
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startIndex); =HJ)!(
} tqI]S
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public PaginationSupport findPageByCriteria 5AmYrXZ
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(final DetachedCriteria detachedCriteria, finalint N}ur0 'J0
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pageSize, k-;%/:Om
finalint startIndex){ pqaQ% |<
return(PaginationSupport) 63hOK
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getHibernateTemplate().execute(new HibernateCallback(){ AvW2)+6G
publicObject doInHibernate G2#={g{
s>}ScJZK
(Session session)throws HibernateException { oU }eAZj{
Criteria criteria = #qL?;Zh0S
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detachedCriteria.getExecutableCriteria(session); /I[?TsXp
int totalCount = g\sW2qXEw
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((Integer) criteria.setProjection(Projections.rowCount 88 fH!6b
T /iKz
()).uniqueResult()).intValue(); 2&*r1NXBE
criteria.setProjection |\g =ua+h
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(null); =-#>NlB$w
List items =
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criteria.setFirstResult(startIndex).setMaxResults p( EV-^
)vH6N _
(pageSize).list(); PoyY}Ra
PaginationSupport ps = j$l[OZ:#
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new PaginationSupport(items, totalCount, pageSize, 2=H3yEJq
IooAXwOF
startIndex); Uloa]X=Im8
return ps; Jb'l.xN
} #X&`gDW
}, true); I!IWmU6FN
} }UwDHq=
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public List findAllByCriteria(final RS&l68[6
rCGyr}(NC
DetachedCriteria detachedCriteria){ 9|yn{4E
return(List) getHibernateTemplate v-`RX;8
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().execute(new HibernateCallback(){ V=!tZ[4z$h
publicObject doInHibernate r)$(>/[$
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(Session session)throws HibernateException { NABwtx>.
Criteria criteria = Zy0u@``
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detachedCriteria.getExecutableCriteria(session); zyNg?_SM
return criteria.list(); lp`raNNo
} 98u$5=Z'/
}, true); ?`PG`|2~
} \iFh-?(
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public int getCountByCriteria(final {Lj]++`fB]
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DetachedCriteria detachedCriteria){ b/N+X}VMN
Integer count = (Integer) %X(iAoxbj
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getHibernateTemplate().execute(new HibernateCallback(){ *QAcp` ;*
publicObject doInHibernate =n_r\z
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(Session session)throws HibernateException { Bob K>db
Criteria criteria = yyZV/
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detachedCriteria.getExecutableCriteria(session); h^E"eC
return ZTV|rzE
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criteria.setProjection(Projections.rowCount @ToY,@]e
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()).uniqueResult(); rt+%&%wt
} \v(}@zcB|
}, true); XW]'by
return count.intValue(); $RxS<_tj
} &6-udZB-
} @ i$jyc
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用户在web层构造查询条件detachedCriteria,和可选的 sJ{S(wpi"
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Opc, {,z6
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PaginationSupport的实例ps。 }Gmwm|`*
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ps.getItems()得到已分页好的结果集 n&V \s0
ps.getIndexes()得到分页索引的数组 L+s3@C;b
ps.getTotalCount()得到总结果数 &s.S)'l4l
ps.getStartIndex()当前分页索引 NRU&GCVwu
ps.getNextIndex()下一页索引 SGi(Zkc
ps.getPreviousIndex()上一页索引 CAX)AN
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Z(F`M;1>xI
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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 XcfvmlBoD-
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一下代码重构了。 B(+J?0Dj
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我把原本我的做法也提供出来供大家讨论吧: L\1&$|?
n#F:(MSOp
首先,为了实现分页查询,我封装了一个Page类: 9"T&P_
java代码: `_`\jd@
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/*Created on 2005-4-14*/ fO6i
package org.flyware.util.page; Pc"g
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/** rVo0H.+N)`
* @author Joa =1qM`M
* 2$G,pT1J
*/ @3T)J,f
publicclass Page { NGsG4y^g?z
$\:;N]Cs~0
/** imply if the page has previous page */ BhJag L ^o
privateboolean hasPrePage; zQpF,N<b
Ct-^-XD
/** imply if the page has next page */ *^|.bBG
privateboolean hasNextPage; AmSrc.
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/** the number of every page */ {<f |h)r
privateint everyPage; Yz6+
x]
*qM)[XO
/** the total page number */ m-%.LDqM
privateint totalPage; IrIF 853g
,OGXH2!h
/** the number of current page */ y2nwDw(xF
privateint currentPage; Pe-1o#7~W
>M~wFs$~
/** the begin index of the records by the current :=CRsQAn
J.%%]-f=&
query */ zTP|H5HyK
privateint beginIndex; h^Bp^V5#
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/** The default constructor */ |}hV_
public Page(){ CFo>D\*J
y+R*<5qC<
} st91rV$y?
)21yD1"6
/** construct the page by everyPage ()Cw;N{E
* @param everyPage &\w:jI44Bs
* */ ^)\z
public Page(int everyPage){ S.iCkX
this.everyPage = everyPage; *Fb|iR
} y5oC|v7
f9ziSD#
/** The whole constructor */ tN-U,6c]
public Page(boolean hasPrePage, boolean hasNextPage, P&3Z,f0
9hbn<Y
/b
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int everyPage, int totalPage, 2|n)ZP2cp
int currentPage, int beginIndex){ 9/LnO'&-
this.hasPrePage = hasPrePage; -FxE!K
this.hasNextPage = hasNextPage; JZc"4qf@OT
this.everyPage = everyPage; R:[IH2F s
this.totalPage = totalPage; KUR9vo
this.currentPage = currentPage; vCj,aSW
this.beginIndex = beginIndex; &@dMIJK"(
} -~PiPYX
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/** @)iAV1r"
* @return U/p|X)
* Returns the beginIndex. ke~S[bL%-
*/ # Vq"Cf
publicint getBeginIndex(){ o?T01t=
return beginIndex; O|ODJOQNol
} `fL81)!jI#
[H-r0Ah
/** G/y@`A)
* @param beginIndex Y\Grf$e
* The beginIndex to set. -n>JlfCd2
*/ n"Gow/-;
publicvoid setBeginIndex(int beginIndex){ =x QLf4>
this.beginIndex = beginIndex; czp .q
} K1*oYH B
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/** {(00,6M)i
* @return h3udS{9'8
* Returns the currentPage. \os iY^
*/ JsDugn ,B
publicint getCurrentPage(){ e
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return currentPage; BZdryk:S
} |^&j'k+A
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/** 2A,iY}R
* @param currentPage U"0Ts!CABA
* The currentPage to set. BS(XEmJn&j
*/ @ xBw'
publicvoid setCurrentPage(int currentPage){ C=y[WsT
this.currentPage = currentPage; X~#jx(0_
} EId_1F;V^
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/** zA<Hj;9SM
* @return "&@v[O)!xu
* Returns the everyPage. &OXnZT3P
*/ )9PP3" I
publicint getEveryPage(){ eG
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return everyPage; 0}:wM':G
} |K7zN\
Wq
}BR@vY'd
/** bAd$
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* @param everyPage Ie<`WU K
* The everyPage to set. q|EE
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*/ '9w.~@7
publicvoid setEveryPage(int everyPage){ kr=&x)Wy!
this.everyPage = everyPage; 4!3mS WNV
} |IgH0
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/** h^`!kp
* @return R,
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* Returns the hasNextPage. doj$chy
*/ >axf_k
publicboolean getHasNextPage(){ L<`p;?
return hasNextPage; ;OTd<
} piy_9nk
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/** kCuIEv@
* @param hasNextPage LY? `+/
* The hasNextPage to set. H:x{qS4Si
*/ ivi,/~L
publicvoid setHasNextPage(boolean hasNextPage){ HAHLF+k
this.hasNextPage = hasNextPage; j)vfI>
} 1~|o@CO
8}A+{xVp8
/** J8>8@m6
* @return :RqTbE4B
* Returns the hasPrePage. 3u tJlD
*/ xi!CZNz
publicboolean getHasPrePage(){ AlH\IP
return hasPrePage; KK|AXoBf
} 6cm&=n_u
$Qc`4x;N
/** q\xT
* @param hasPrePage [og_0;
* The hasPrePage to set.
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*/
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publicvoid setHasPrePage(boolean hasPrePage){ VD).UdUn
this.hasPrePage = hasPrePage; DNu^4#r
} ([+u U!
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/** ar#Xe;T!
* @return Returns the totalPage. u5LrZt]k
* EU0b>2n4
*/ FkS$x'~2$
publicint getTotalPage(){ >3J?O96|f
return totalPage; >w}5\4j
} E/Ng
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/** G[[hC[}I
* @param totalPage Z_tK3kQa@&
* The totalPage to set. W
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*/ ='p&T|&
publicvoid setTotalPage(int totalPage){ UmC_C[/n?
this.totalPage = totalPage; ,{tK{XpS
} :hA=(iz
|hlc#t?
} ];n3H~2
7[)IP:I>
wE4:$+R};
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 z(yJ/~m
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个PageUtil,负责对Page对象进行构造: H fg2]N
java代码: HF\|mL
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/*Created on 2005-4-14*/ d8o<Q 9
package org.flyware.util.page; qMj'% 5/
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import org.apache.commons.logging.Log; y7?n;3U]CS
import org.apache.commons.logging.LogFactory; ioZ{2kK
YKk*QcAn
/** VPAi[<FzOG
* @author Joa z3\WcW7|
* 5ml#/kE
*/ YaWZOuxm
publicclass PageUtil { ST*\ Q
=gYKAr^p5
privatestaticfinal Log logger = LogFactory.getLog 1F*3K3T {
";PW#VHC
(PageUtil.class); .*3.47O
}K8W%h<3S
/** Wvg+5Q
* Use the origin page to create a new page }ob&d.XZ
* @param page .w .`1
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* @param totalRecords S*5hO) C
* @return 6~t;&)6J
*/ M$O*@])
publicstatic Page createPage(Page page, int W'B=H1
AD** 4E
totalRecords){ [nx
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return createPage(page.getEveryPage(), Xv~v=.HNhk
L7}dvdtZ0
page.getCurrentPage(), totalRecords); f
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} 'DDlX3W-
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/** 6hW ~Q
* the basic page utils not including exception WaaF;|,(
2EU((Q`>=(
handler 6w )mo)<X
* @param everyPage D #`o
* @param currentPage Exy|^Dr0
* @param totalRecords d;<gwCc
* @return page gE_i#=bw
*/ m#^ua^JV
publicstatic Page createPage(int everyPage, int f<$>?o&y
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currentPage, int totalRecords){ #%=6DHsK
everyPage = getEveryPage(everyPage); &"h 9Awn2
currentPage = getCurrentPage(currentPage); ,k,RXgQ
int beginIndex = getBeginIndex(everyPage, e?V7<7$
TVVr<r
currentPage); ^iHwv*ss
int totalPage = getTotalPage(everyPage, t,f)!D$
'UW(0 PXw
totalRecords); q$<M2
boolean hasNextPage = hasNextPage(currentPage, \$iU#Z
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totalPage); !ULU#2'1
boolean hasPrePage = hasPrePage(currentPage); eLvbPE_
)37 .H^7
returnnew Page(hasPrePage, hasNextPage, ['*{f(AI
everyPage, totalPage, gq'}LcV
currentPage, ;VLv2J*
e\[z Q
2Z3
beginIndex); E/OJ}3Rf
} -$;
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b,k%n_&n
privatestaticint getEveryPage(int everyPage){ rmzM}T\20
return everyPage == 0 ? 10 : everyPage; Ub(8ko:8$
} nQ$4W
m,u5S=3A{!
privatestaticint getCurrentPage(int currentPage){ S m%\,/3
return currentPage == 0 ? 1 : currentPage; +p:?blG
} (D?%(f
4F-r }Fj3
privatestaticint getBeginIndex(int everyPage, int MKnG:)T<?l
4GiHp7Y&A
currentPage){ D^[}:O{
return(currentPage - 1) * everyPage; C0eqCu)Q
} YV6@SXy
"<e<0::
privatestaticint getTotalPage(int everyPage, int @AvDV$F
ptCFW_UV
totalRecords){ IQ5H`o?[B
int totalPage = 0; cEP!DUo
cIm_~HH
if(totalRecords % everyPage == 0) (Ov{gj^
totalPage = totalRecords / everyPage; )t$<FP
else /YyimG7
totalPage = totalRecords / everyPage + 1 ; _D{V(c<WD
\BoRYb9h
return totalPage; M<A jtDF%
} A<1:vV
tR!!Q
privatestaticboolean hasPrePage(int currentPage){ |<Cz#|
,q
return currentPage == 1 ? false : true; 3k#?E]'
} ae&i]K;
TIs~?wb$
privatestaticboolean hasNextPage(int currentPage, TpHvZ]c
DaA9fJ7a
int totalPage){ d~G, *
return currentPage == totalPage || totalPage == D.Q9fa&P
!vaS fL*]
0 ? false : true; p}b:(QN~m
} 015
;'V#we
dTE(+M-
Gr
\o&\r)FX
} c7E|GZ2Hc
z
?3G`
g}cb>'=={
Y]u6f c
TL29{'4V
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。 +*O$]Hh
8RA]h?$$J
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 H}Jdnu| ko
&gP/<!#
做法如下: *an^
0
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 L,(H(GeX
b`lLqV<[cB
的信息,和一个结果集List: ~ x!"(
java代码: '=M4(h
I3ZlKI
%![%wI?
/*Created on 2005-6-13*/ N=JZtf/i
package com.adt.bo; pG|+\k/B
*2?-6
import java.util.List; CTNeh%K;
dGNg[
import org.flyware.util.page.Page; 'e/= !"T
"vH>xBR[%
/** tK|jh
* @author Joa pX\Y:hCug
*/ *_qW;l7
publicclass Result { E#0_y4
>Q`\|m}x)Q
private Page page; )jS9p~FS
hk +@ngh%
private List content; ]c Or$O*
D~(f7~c%
/** LU7ia[T
* The default constructor \8KAK3i'
*/ 0xSWoz[i6~
public Result(){ rryC^Vma
super(); ytWTJ>L
} qwERy{]Sp;
:4 &q2-
/** \\Z{[{OZ
* The constructor using fields "%mu~&Ga
* cnm*&1EzV
* @param page Y]9AC
* @param content e
hgUp =
*/ Fm| h3.`V
public Result(Page page, List content){ q
JdC5z\[
this.page = page; d'x'hp%
this.content = content; wa)E.(x
} [!<W{ ($5
M9t`w-@_w
/** ::lD7@Wg
* @return Returns the content. w@jC#E\
*/ J%:D%=9 )
publicList getContent(){ UhI T!x
return content; 5Nt40)E}sN
} 7V="/0a
Cuk!I$
/** mZ[tB/
* @return Returns the page. #77p>zhY
*/ y|+n77[Gv
public Page getPage(){ wqZ*$M
return page; :Sd"~\N+
} q#6K'=AC
)R- e^Cb
/** ) ]y^RrD
* @param content JM&:dzyIP
* The content to set. CY4ntd4M
*/ $ YPU(y
public void setContent(List content){ HQ7
this.content = content; q_R^Q>ZIe
} BM }{};p6
}OJ,<!v2pc
/** 2`]`nTz,
* @param page ##+f/Fxym
* The page to set. T2%{pcdV/
*/ fbjT"jSzw
publicvoid setPage(Page page){ av!'UZP
this.page = page; ]9 ArT$
} D2@J4;UW*W
} 8M_p'AR\,y
b}C6/zW
CZ~%qPwDw
$3BH82
p
bT sn
2. 编写业务逻辑接口,并实现它(UserManager, ?kF_C,k/>N
#cF ?a5
UserManagerImpl) CkHifmc(u-
java代码: X`+8rO[
^T.icSxP
8Q*477=I
/*Created on 2005-7-15*/ Y~fa=R{W
package com.adt.service; n6 VX0R
in[yrqFb7t
import net.sf.hibernate.HibernateException; mZgYR~
F s{}bQyQ
import org.flyware.util.page.Page; "A>/m"c]*
%"C%pA
import com.adt.bo.Result; ;r1.Uz(
NmH:/xU?^
/** oE;SZ"$x
* @author Joa d$;1%rRj8
*/ v<Ozr:lL
publicinterface UserManager { |#Q4e51H
~R$Ko(N
public Result listUser(Page page)throws pAY[XN
$Rd]eC
HibernateException; zg[.Pws:E
1%^d<%,]
} kvoEnwBe_
Tl%n|pc
FZi'#(y
UEb'b,O_9
|nu)=Ag
java代码: `;R
[*7
IuW5LS
8#_"WzDw
/*Created on 2005-7-15*/ A
$GiO
package com.adt.service.impl; -:jC.}
Y
8K;wX%_,
import java.util.List; h88IP:bo
Y;B#_}yF
import net.sf.hibernate.HibernateException; f'-)
3T
@&4s)&-F
import org.flyware.util.page.Page; }vof| (Yh
import org.flyware.util.page.PageUtil; "x"y3v'
h{BO\^6x
import com.adt.bo.Result; _ITA $#
import com.adt.dao.UserDAO; 9si,z
import com.adt.exception.ObjectNotFoundException; mKh<M)Bz
import com.adt.service.UserManager; F VVpyB|
LL}b]B[
/** M,WC+")Z=
* @author Joa {-'S#04
*/ 4pw:O^v
publicclass UserManagerImpl implements UserManager { Rc.8j,]
x#0B
"{
private UserDAO userDAO; Q|1X|_hs
E{#Y=
/** J nzI-
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* @param userDAO The userDAO to set. 1oVjx_I5y
*/ L74Sx0nk=
publicvoid setUserDAO(UserDAO userDAO){ 28jm*Cl8
this.userDAO = userDAO; GO|EeM!iB
} \.AI;^)X@]
B;6N.X(K
/* (non-Javadoc) @?gN
&Z)I
* @see com.adt.service.UserManager#listUser C\d5t4s
ud@7%%
(org.flyware.util.page.Page) ~p'DPg4
*/ S^/:O.X)c,
public Result listUser(Page page)throws Z9+xB"q2
w?db~"T
HibernateException, ObjectNotFoundException { FE[{*8
int totalRecords = userDAO.getUserCount(); 6lKM5,Oa
if(totalRecords == 0) 7K\H_YY8#
throw new ObjectNotFoundException OM4q/!)A]
HXg4
T
("userNotExist"); Z"u|-RoBV
page = PageUtil.createPage(page, totalRecords); @m99xF\e
List users = userDAO.getUserByPage(page); rQ!X
returnnew Result(page, users); p#T^o]+
} j%Cr)'H?
Z?o?"|o
} IY=CTFQ8lm
~l@-gAyw
3~uWrZ.u
GA.4'W^&a
rdY/QvP0=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 x.:k0;%Q
R{hq1-
询,接下来编写UserDAO的代码: |!=KLJUA
3. UserDAO 和 UserDAOImpl: Ov5*&*P
java代码: U if61)+!i
Q x]zz4jD
dreEe s`|
/*Created on 2005-7-15*/ hV6=-QL*B
package com.adt.dao; u3XQ<N{Gj
faJ>,^V#
import java.util.List; 1}$GVb%i
wzka4J {
import org.flyware.util.page.Page; V(LE4P1
/cN. -lEo%
import net.sf.hibernate.HibernateException; k.dQ;v}
IxxA8[^V
/** @N'0:0Nb_
* @author Joa {q}#
Sq
*/ C6neZng
publicinterface UserDAO extends BaseDAO { ly)b=ph&
"~uo4n~H
publicList getUserByName(String name)throws dAZh# i[
XM"{"
HibernateException; Gf|qc>j.b
>dTJ
publicint getUserCount()throws HibernateException; ,cqZb0VP{t
mI[$c"!BD
publicList getUserByPage(Page page)throws [Tq\K ^!^
VIi/=mO]
HibernateException;
, 7kS#`P
\;%DDw
} UFED*al#
t'F_1P^*/
Wxxnc#;lv
.-(s`2
?R;K`f9<
java代码: 5%5z@Ka
@}^eyS$|!
f/VrenZ_
/*Created on 2005-7-15*/ dLtn,qCX0^
package com.adt.dao.impl; "Y7
]t:8
3X,SCG
import java.util.List; =?, dX
\s[/{3
import org.flyware.util.page.Page; $7 08\!
Y8fahQ#
import net.sf.hibernate.HibernateException; ZMVQo-=
import net.sf.hibernate.Query; o@d+<6Um
Zk4(
import com.adt.dao.UserDAO; 3V"y|q
o5 fXe}pl@
/**
A`D^}F6
* @author Joa rLfhm
Ds%u
*/ eZr}xo@9
public class UserDAOImpl extends BaseDAOHibernateImpl m R? } gR
V(Dn!Nz
implements UserDAO { >;;tX3(
#n[1%8l,
/* (non-Javadoc) Yp_R+a^
* @see com.adt.dao.UserDAO#getUserByName ppBIl6
P 3CzX48^
(java.lang.String) $)5-}NJf'
*/ (M5{y`Kk
publicList getUserByName(String name)throws !Hk$ t
R&OqmhT!
HibernateException { OEkx}.w
String querySentence = "FROM user in class .skR4f,h
l^F%fIRp)
com.adt.po.User WHERE user.name=:name"; ^rDT+ x
Query query = getSession().createQuery nn"Wn2ciS
^rKA=siz
(querySentence); wM^_pah#Y5
query.setParameter("name", name); X2MQa:yksP
return query.list(); ?8d7/KZO
} nA\9UD<G.
4l2xhx
/* (non-Javadoc) es` A<
* @see com.adt.dao.UserDAO#getUserCount() wlh V!a0>
*/ Tu'/XUs;k
publicint getUserCount()throws HibernateException { XQ{G)
int count = 0; v%e-vl
String querySentence = "SELECT count(*) FROM P`^{dH$P
4RH'GnLa
user in class com.adt.po.User"; eDm~B(G$
Query query = getSession().createQuery C(7Y5\"P
f4s^$Q{Q
(querySentence); G*;}6 bj|?
count = ((Integer)query.iterate().next tv)U 7K0
-bamNw>|
()).intValue(); $=c79Al(
return count; tp3>aNj
} b,U3b})(
T/_JXK>W
/* (non-Javadoc) Y!kz0([
* @see com.adt.dao.UserDAO#getUserByPage *hHy>(*
,u^S(vxyz
(org.flyware.util.page.Page) z_dorDF8`>
*/ s{- `y`JP
publicList getUserByPage(Page page)throws aN.t) DG}J
{ZS-]|Kx
HibernateException { L29,Y=n@
String querySentence = "FROM user in class Vs1j9P|G
[\M=w7
com.adt.po.User"; 2>.2H
Query query = getSession().createQuery OZF^w[ `w
zs@#.OEH
(querySentence); j;tT SNF
query.setFirstResult(page.getBeginIndex()) P}%0YJ$6
.setMaxResults(page.getEveryPage()); J{gqm
return query.list(); Sd3KY9,
} &AMW?vO
u#8J`%g
} b"ypS7
_
n.{+\M6k
u7=jtB
VK*2`Z1
H:X=v+W
至此,一个完整的分页程序完成。前台的只需要调用 VWlOMqL995
U8Pnt|0 M
userManager.listUser(page)即可得到一个Page对象和结果集对象 R;P>_ei(LK
<"uT=]wZ=
的综合体,而传入的参数page对象则可以由前台传入,如果用 o@`&
h}
$
[mSK!Y@u
webwork,甚至可以直接在配置文件中指定。 jhWNMu
FQR{w
下面给出一个webwork调用示例: >-Qg4%m
java代码:
P&/PCSf
^N!l$&=
*-timVlaE
/*Created on 2005-6-17*/ 74 c1i
package com.adt.action.user; D!.
r$i)
Ul?Ha{W
import java.util.List; A2o;YyF
S8O^^jJq;
import org.apache.commons.logging.Log; .wrNRU7s
import org.apache.commons.logging.LogFactory; =a`l1zn8=
import org.flyware.util.page.Page; ~-,P1u!
+e0]Y8J{
import com.adt.bo.Result; !*:Zcg?7n
import com.adt.service.UserService; Hp_3BulS<
import com.opensymphony.xwork.Action; ,`/J1(\nd
O[3AI^2
/** t6;Ln().Hw
* @author Joa um@RaU
*/ zaX!f~;"
publicclass ListUser implementsAction{ A#W%ud4
/;M0tP
privatestaticfinal Log logger = LogFactory.getLog GNXQD}L?b?
TxhTK5#f
(ListUser.class); //G5lW/*
jfyV9)
private UserService userService; zh$[UdY6
[=Wn7cr
private Page page; p6(n\eg R
% Ke:%##Y
privateList users; L&qzX)
DRD%pm(
/* R1z\b~@"
* (non-Javadoc) q P@4KH}e
* oJK]oVX9i
* @see com.opensymphony.xwork.Action#execute() 5=g{%X
*/ G 3P3
publicString execute()throwsException{ Xc2Oa
Result result = userService.listUser(page); p+ymtPF
page = result.getPage(); OHzI!,2]
users = result.getContent(); m :ROq
return SUCCESS; br"p D-}
} fbSl$jn.
uXuMt
a*Y
/** o<e AZ
* @return Returns the page. N}wi<P:*)
*/ x`^~|Q
public Page getPage(){ vJ$#m_aa
return page; 6uQfe?aD
} 9hI4',(rE
o}p6qB=;1
/** wobTT1!|
* @return Returns the users. dL>0"UN}-
*/ z3b8
publicList getUsers(){ }io9Hk>|
return users; x~xaE*r
} ?Zu=UVb
u0h {bu
/** 2RKI M(~
* @param page g% :Q86u
* The page to set. GmN} +(
*/ FqiCzP4
publicvoid setPage(Page page){ -san%H'
this.page = page; 7t\W{y
} h\KQ{-Bl
5tR<aIf
/** 6a PZW
* @param users 3|RfX
* The users to set. F ]\4<
*/ .eW}@1+[;
publicvoid setUsers(List users){ ecA[
this.users = users; FsZF>vaV
} G*e/Ft.wf8
`9eE139V='
/** E/:<9xl
* @param userService ?gjM]Ki%:
* The userService to set. _ Onsfv
*/ >t u3m2
publicvoid setUserService(UserService userService){ J'y*;@4l^:
this.userService = userService; 5<Cu-X
} Ul OoMGg
} m.-l&@I2/<
l%lkDh!$"
08vA;6zt
%MgQ.
{<&I4V@+
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, g ZhE\
4xU[oaa
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 ~f2H@#
nCEt*~t9VE
么只需要: FJo N"X
java代码: It!%/Y5
B[ooT3V
2|(J<H
<?xml version="1.0"?> ?stx3sZ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork `DO`c>>K
YEAiL C+q
1.0//EN" "http://www.opensymphony.com/xwork/xwork- uXW<8(
%W
w``t"v4
1.0.dtd"> yInW?3
BqK|4-Pf
<xwork> k}l5v)m
e{.2*>pH
<package name="user" extends="webwork- "m ):"
{
dw m>a
interceptors"> 5NbI Vz
Fkj\U^G
<!-- The default interceptor stack name +wwpaR`
J`;G9'n2
--> ,ju 1:`
<default-interceptor-ref 8$-Wz:X&
MOP
%vS
name="myDefaultWebStack"/> e2UbeP
Ps7( 4%
<action name="listUser" +w:[By"
Z<K[
class="com.adt.action.user.ListUser"> ,g@U*06
<param ,SuF1&4
{ ;);E
name="page.everyPage">10</param> 8 wQV^G
<result [oKc<o7)~"
@~'c(+<3
name="success">/user/user_list.jsp</result> 8Z:NT_Ss
</action> uu1-` !%
~UB@IV6O
</package> gCz^JM
~HI|t2C
</xwork> {>fvyF
v-Ggf0RF
\06fP4?
}3j/%oN.(
1\{0z3P
'wvZnb
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 1wuLw Ad
<a2t"rc
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 D$;mur'
j\f;zb?F
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 jY$Bns&.w
2!cP[Ck
E {4/$}
}&d]Uv/4
M' "S:
我写的一个用于分页的类,用了泛型了,hoho ueZ `+g~gg
5[]7baO)h1
java代码: zv||&Hi
.Gh-T{\V'
thOQcOf0$
package com.intokr.util; 0XSZ3dY&+
;n00kel$
import java.util.List; EN` --^
P )_g t
/** 3X89mIDr
* 用于分页的类<br> &Ph@uZ\
* 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 o 2$
* YMj
z,N
* @version 0.01 ueDG1)
* @author cheng ?%i|].<-'
*/ Cd#[b)d ?^
public class Paginator<E> { FGG Fi(
privateint count = 0; // 总记录数 PbJn8o
privateint p = 1; // 页编号 bqFGDmu6'
privateint num = 20; // 每页的记录数 66fvS}x
privateList<E> results = null; // 结果 s[nXr
Dsw(ti`@
/** ])'22sY
* 结果总数 vi["G7
*/ .AH#D}m
publicint getCount(){ ;t:B:4r(j
return count; "639oB
} X2(TuR*t
tk|Ew!M:
publicvoid setCount(int count){ 0qnToV;
this.count = count; h35x'`g7+r
} 2Y\,[ $z
B<xBuW
/** -@Mr!!t?N
* 本结果所在的页码,从1开始 K:c5Yq^
* lV]hjt-L
2
* @return Returns the pageNo. lJpD>\$}@R
*/ ~zi6wu(3
publicint getP(){ @ >%I\
return p; &=nwb4
} L:IaJ?+?
fJn;|'H!
/** ;3h[=hyS
* if(p<=0) p=1 D!Owm&We
* Ry,_%j3
* @param p R4 ;^R
*/ ]BP"$rs
publicvoid setP(int p){ F]N9ZWn/
if(p <= 0) NYM$0v`0YK
p = 1; $fPf/yQmC
this.p = p; vY7C!O/y_k
} _]E"hr6a
0V{-5-.
/** V?kJYf(<
* 每页记录数量 D*|h
c
*/ s+2\uMwf*
publicint getNum(){ J1cD)nM<A
return num; XG@_Lcv*
} ]QJLES
L}P<iB
/** |F-_YR
* if(num<1) num=1 T12?'JL^r
*/ r4@!QR<h
publicvoid setNum(int num){ f7)}A/$4+
if(num < 1) o )GNV
num = 1; wz +
this.num = num; ) 2wof(
} I?c# T Rm
6 KP
/** WpP8J1KN[
* 获得总页数 br.jj
*/ { .B^
publicint getPageNum(){ bqJL@!T
return(count - 1) / num + 1; u3R0_8
_.w
} "pa5+N&2-
+M$2:[xRT
/** F[ N{7C3
* 获得本页的开始编号,为 (p-1)*num+1 v}Gq.(b
*/ r50}j
publicint getStart(){ >k<.bEx(A
return(p - 1) * num + 1; ?5K.#>{
} FTI[YR8?Y
IxAKIa[HY
/** 36`aG Y
* @return Returns the results. ^2mmgN
*/ /0s1q
publicList<E> getResults(){ bmr.EB/
return results; L7el5Q!Y=
} U;Se'*5xv
*LOpbf
public void setResults(List<E> results){ pa N )t
this.results = results; 1Cki}$k@
} ]sE~gro
(NyS2`
public String toString(){ ,
?WTX
StringBuilder buff = new StringBuilder 1@"eeR
J
[J,
(); @QV|<NeH
buff.append("{"); :/c=."z.
buff.append("count:").append(count); PaP47>(
buff.append(",p:").append(p); F8$.K*tT
buff.append(",nump:").append(num); M&Sjo' ( .
buff.append(",results:").append h`-aO u
C|5eV=f)P
(results); R!0O[i
buff.append("}"); Qv(}*iq]
return buff.toString(); 0V`s 3,k
} +e);lS"+/
"1$OPt5
} {(U?)4@
8`Q8Mct$<
q]T{g*lT