Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :cem,#(=
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 =.f-w0V
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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 #~}nFY.
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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 ZM!CaR
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分页支持类: n'wU;!W9
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java代码: 8_BV:o9kL
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package com.javaeye.common.util; 9YIM'q>`v
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import java.util.List; +Mo9kC
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publicclass PaginationSupport { tZ:_ag)o
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publicfinalstaticint PAGESIZE = 30; fi-WZ
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privateint pageSize = PAGESIZE; z1PBMSG
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privateList items; q0i(i.h
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privateint totalCount; gPNZF\ r
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privateint[] indexes = newint[0]; 3oGt3F{gZ
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privateint startIndex = 0; gf#{k2r
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public PaginationSupport(List items, int dA@]!
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totalCount){ [;4g
setPageSize(PAGESIZE); \\PjKAsh
setTotalCount(totalCount); ][gq#Vx@
setItems(items); iV5yJF{ZH
setStartIndex(0); hm84Aq= f
} tX9{hC^
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public PaginationSupport(List items, int jqWu
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totalCount, int startIndex){ Fsmycr!R
setPageSize(PAGESIZE); E
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setTotalCount(totalCount); >BR(Wd.
setItems(items); oX#Q<2z*
setStartIndex(startIndex); `slL%j^"
} Y l4^AR&
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public PaginationSupport(List items, int nOt&pq7
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totalCount, int pageSize, int startIndex){ rXmn7;B}g
setPageSize(pageSize); *]ly0nP
setTotalCount(totalCount); y?[ v=j*U
setItems(items); <{dVKf,e
setStartIndex(startIndex); r@72|:,
} "Q}#^h]F
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publicList getItems(){ j@W.&- _
return items; '-r).Xk
} 6LOnU~l,
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publicvoid setItems(List items){ ;+W#5<i
this.items = items; u!!Y=!y*<
} H{@Yo\J
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publicint getPageSize(){ j#X.KM
return pageSize; gFeO}otm
} kW2sY^Rg
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publicvoid setPageSize(int pageSize){ AYt%`Y.!
this.pageSize = pageSize; 3C?f(J}
} xHUsFms
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publicint getTotalCount(){ ZOft.P O
return totalCount; In:9\7~jC
} $h2){*5E{
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publicvoid setTotalCount(int totalCount){ K$&s=Hm
if(totalCount > 0){ )bS~1n_0
this.totalCount = totalCount; wF
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int count = totalCount / q$ZHd
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pageSize; ?zeJ#i
if(totalCount % pageSize > 0) ^WHE$4U`
count++; o>).Cj
indexes = newint[count]; @E;=*9ek{u
for(int i = 0; i < count; i++){ 4iqoR$3Fc
indexes = pageSize * LIS)(X<]?
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i; *EOdEFsR/
} ?^H
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}else{ _g+JA3sIJ
this.totalCount = 0; Vu)4dD!
} |*oZ_gI
} Keuf9u
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publicint[] getIndexes(){ G^~k)6v=m
return indexes; B:dB,3,`(
} D2<fw#
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publicvoid setIndexes(int[] indexes){ W}3.E "K
this.indexes = indexes; /,89p&h
} 1%EBd%`#
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publicint getStartIndex(){ T?:Rdo!:u
return startIndex; NgADKrDU
} $LKIT0
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publicvoid setStartIndex(int startIndex){ hLI`If/+K
if(totalCount <= 0) W}--p fG
this.startIndex = 0; m`v2: S}
elseif(startIndex >= totalCount) #Vl 0.l3
this.startIndex = indexes I, -hf=-
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[indexes.length - 1]; V `b2TS
elseif(startIndex < 0) M3J#'%$
this.startIndex = 0; ?HTjmIb
else{ E%+Dl=
this.startIndex = indexes &)8:h+&Z
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[startIndex / pageSize]; 0@yXi
} b o0^3]Z
} ;,$NAejgd
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publicint getNextIndex(){ ^@I
int nextIndex = getStartIndex() + pM^9c7@!:
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pageSize; IM:=@a{
if(nextIndex >= totalCount) |M>eEE*F<
return getStartIndex(); 6BY-^"W5`
else oeKHqP wg
return nextIndex; K\>tA)IPSV
} kd=GCO
__`*dL>*
publicint getPreviousIndex(){ VcAue!MN
int previousIndex = getStartIndex() - *YW/_
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pageSize; 3t`P@nL0;
if(previousIndex < 0) IYqBQnX}oM
return0; @En^wN
else g3Ec"_>P
return previousIndex;
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} aHs^tPg
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} =CK4.
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抽象业务类 g+DzscIT
java代码: _6_IP0;
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/** w ihH?~]
* Created on 2005-7-12 aY3^C q(r
*/ 1)9sf0LyU
package com.javaeye.common.business; j;']cWe
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import java.io.Serializable; +)k b(
import java.util.List; $h^wG)s2P
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import org.hibernate.Criteria; |s)Rxq){"V
import org.hibernate.HibernateException; L>MLi3{
import org.hibernate.Session; ,RE\$~`w
import org.hibernate.criterion.DetachedCriteria; CJ(NgYC h
import org.hibernate.criterion.Projections; '/`= R
import eKgisY4#
y@ ML/9X8q
org.springframework.orm.hibernate3.HibernateCallback; ykv94i?Q
import ;E@G`=0St
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org.springframework.orm.hibernate3.support.HibernateDaoS |B.0TdF
_= +V/=
upport; ,pqGX3
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import com.javaeye.common.util.PaginationSupport; J+[_Wd
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public abstract class AbstractManager extends
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HibernateDaoSupport { >^%7@i:@U
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privateboolean cacheQueries = false; pV.Av
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privateString queryCacheRegion; el2bd
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publicvoid setCacheQueries(boolean A{UULVp
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cacheQueries){ {8 8 )~
this.cacheQueries = cacheQueries; eyefW n&
} kdCUORMK
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publicvoid setQueryCacheRegion(String D|@/yDQ
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queryCacheRegion){ xm%Um\Pb7
this.queryCacheRegion = =jlt5 z
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queryCacheRegion; &Ts-a$Z7?S
} eK.e|z|
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publicvoid save(finalObject entity){ >"gf3rioW
getHibernateTemplate().save(entity); W4[V}s5u
} )A!>=2M`
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publicvoid persist(finalObject entity){ OC1I&",Ai|
getHibernateTemplate().save(entity); }-ftyl7
} $SM#< @
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publicvoid update(finalObject entity){ )_{dWf1
getHibernateTemplate().update(entity); ulu9'ch
} t>1Z\lE\"
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publicvoid delete(finalObject entity){ x;-.
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getHibernateTemplate().delete(entity); )p
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} rrQQZ5fh b
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publicObject load(finalClass entity, CF+_/s#j^
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finalSerializable id){ u`y><w4i
return getHibernateTemplate().load T6H}/#*tK
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(entity, id); Qi_>Mg`x
} b`)){LR
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publicObject get(finalClass entity, CLeG<Hi
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{ T4
finalSerializable id){ z74in8]
return getHibernateTemplate().get T32+3wb"I
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(entity, id); A$#p%yb
} 6fd+Q
/
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publicList findAll(finalClass entity){ fRy^Q_~,
return getHibernateTemplate().find("from ]4h92\\965
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" + entity.getName()); HHq_P/'
} G2t;DN(
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publicList findByNamedQuery(finalString 'rMN=1:iu"
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namedQuery){ <@}I0
return getHibernateTemplate f8M$45A'
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().findByNamedQuery(namedQuery); `!Ds6
} CamE'
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publicList findByNamedQuery(finalString query, o&`<+4
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finalObject parameter){ uHAT#\m:
return getHibernateTemplate "*LD 3
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().findByNamedQuery(query, parameter); 8>X d2X
} dDm):Z*`b
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publicList findByNamedQuery(finalString query, X5X?&* %{
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finalObject[] parameters){ T/^Hz4uA7
return getHibernateTemplate Jrg2/ee,*
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().findByNamedQuery(query, parameters); w"SoeU
} YyTSyP4
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publicList find(finalString query){ oI}kH=<,
return getHibernateTemplate().find DA2}{
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(query); {?J/c{=/P
} :4MB]v[K
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publicList find(finalString query, finalObject Hir Fl
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parameter){ /e]'u&a
return getHibernateTemplate().find ,z;ky5Ct
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(query, parameter); " R-!(9k^`
} OiE;B
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public PaginationSupport findPageByCriteria Si_%Rr&jW
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(final DetachedCriteria detachedCriteria){ P(XaTU&-
return findPageByCriteria s3]?8hXd
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]u4Hk?j~<
} K_2|_MLlZ
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public PaginationSupport findPageByCriteria yaG= j
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(final DetachedCriteria detachedCriteria, finalint ]8T |f
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startIndex){ 'ihhoW8
return findPageByCriteria Qu}W/j|3
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(detachedCriteria, PaginationSupport.PAGESIZE, *+uHQgn(
3&6#F"7
startIndex); M/):e$S
} ?0YCpn
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public PaginationSupport findPageByCriteria ~(pmLZ<GW}
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(final DetachedCriteria detachedCriteria, finalint G7)Fk%>
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pageSize, m;D- u>o
finalint startIndex){ wKi^C8Z2
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ $&<uT
publicObject doInHibernate j'aHF#_
ukv tQz)
(Session session)throws HibernateException { /}Lt,9
Criteria criteria = UK1_0tp]x
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detachedCriteria.getExecutableCriteria(session); 4#5:~M }
int totalCount = w.lAQ5)I%\
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((Integer) criteria.setProjection(Projections.rowCount Q>R>R*1.j
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()).uniqueResult()).intValue(); E@-KGsdhK
criteria.setProjection %e`$p=m
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(null); zfwS
List items = &BtK($
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criteria.setFirstResult(startIndex).setMaxResults 549jWG
#fJ] o_
(pageSize).list(); rQEyD
PaginationSupport ps = 5w\fSY
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new PaginationSupport(items, totalCount, pageSize, K{ \;2M
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startIndex); "Vr[4&`
return ps; ]D@0|
} l#lF
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}, true); &q`q4g&7
} ,(.MmP`
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public List findAllByCriteria(final 0vVV%,v
{0;3W7
DetachedCriteria detachedCriteria){ iSFuT7;%
return(List) getHibernateTemplate Qc[3Fq,f
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().execute(new HibernateCallback(){ =56T{N
publicObject doInHibernate H*bs31i{
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(Session session)throws HibernateException { ?d4m!HgR
Criteria criteria = )@~J
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detachedCriteria.getExecutableCriteria(session); +3a?`Z
return criteria.list(); qim
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} 7T"XPV|W6
}, true); rU;RGz6}
} r1<F
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public int getCountByCriteria(final Ja SI^go
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DetachedCriteria detachedCriteria){ Qj3a_p$)P
Integer count = (Integer) ,ZQZ}`x(
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getHibernateTemplate().execute(new HibernateCallback(){ !r`, =jK"
publicObject doInHibernate 1Nu1BLPm
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(Session session)throws HibernateException { 7},)]da>,'
Criteria criteria = w=|GJ0
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detachedCriteria.getExecutableCriteria(session); R/^u/~<
return `+t.!tv!
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criteria.setProjection(Projections.rowCount >6oOZbUY0
|A%<Z(
()).uniqueResult(); :QWq"cBem
} J*l4|^i<
}, true); oQv3GpO
return count.intValue(); \}~s2Y5j
} Y-'78BJk
} UxD5eJJ
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用户在web层构造查询条件detachedCriteria,和可选的 /T,Z>R
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 =?h~.lo
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PaginationSupport的实例ps。 }|B=h
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ps.getItems()得到已分页好的结果集 ^'p|!`:
ps.getIndexes()得到分页索引的数组 A~Xq,BxCV
ps.getTotalCount()得到总结果数 zZiJ 9 e
ps.getStartIndex()当前分页索引 }n7th
ps.getNextIndex()下一页索引 bu&t'?zx!
ps.getPreviousIndex()上一页索引 aF|d^
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #{9G sD
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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 F`nb21{0y&
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一下代码重构了。 KluA
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我把原本我的做法也提供出来供大家讨论吧: KOg?FmD
[TF8'jI0
首先,为了实现分页查询,我封装了一个Page类: ^uS/r#l
java代码: >xA),^ YT
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/*Created on 2005-4-14*/ ]APvp.Tw:
package org.flyware.util.page; dr{y0`CCN
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/** Omi^>c4G
* @author Joa ?EU\}N J
* |wox1Wt|E
*/ 8h<ehNX ^I
publicclass Page { $6F)R|
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/** imply if the page has previous page */ j5Un1
privateboolean hasPrePage; >)_ojDO
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/** imply if the page has next page */ ec Oy6@UDY
privateboolean hasNextPage; d7cg&9+
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/** the number of every page */ $KjTa#[RX7
privateint everyPage; kCUT ^
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/** the total page number */ 2X-l{n;>
privateint totalPage; fqs]<qi
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/** the number of current page */ ==/n(LBD
privateint currentPage; $jI>[%
TP1S[`nR
/** the begin index of the records by the current 8u2+tB
ni
query */ }.)s%4p8
privateint beginIndex; cgC\mM4Nla
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/** The default constructor */ ,jy*1Hjd
public Page(){ %o?IsIys
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} 5&CDHc7Oj
rZ_>`}O2
/** construct the page by everyPage VohhQ
* @param everyPage kllQca|$4
* */ /?"8-0d
public Page(int everyPage){ 8 _d-81Dd
this.everyPage = everyPage; 1Q}mf !Y
} TO;.eN!sv
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/** The whole constructor */ !C:r b
public Page(boolean hasPrePage, boolean hasNextPage, o@lWBfB*%e
nY `2uN~9
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int everyPage, int totalPage, v_PdOp[
k
int currentPage, int beginIndex){ 0;~yZ?6_F
this.hasPrePage = hasPrePage; dMl+ko
this.hasNextPage = hasNextPage; YEYY}/YX
this.everyPage = everyPage; Qq0l*)mX
this.totalPage = totalPage; b'x$2K;E
this.currentPage = currentPage; rFJ[dz
this.beginIndex = beginIndex; %-;bu|
} yy2Ie
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/** AyE\fY5
* @return MM{_Ur7Q
* Returns the beginIndex. W( *V2<$o
*/ Em13dem
publicint getBeginIndex(){ N~=A
return beginIndex; `GQ{*_-
} RE46k`44
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/** a0Oe:]mo\
* @param beginIndex -E&e1u,Mi
* The beginIndex to set. ul5|.C
*/ !)Ni dG
publicvoid setBeginIndex(int beginIndex){ ]Ql 0v"` F
this.beginIndex = beginIndex; OCyG_DLT$5
} !UV5zmS
#Gv{UU$]
/** d<o.o?Vc
* @return i6no;}j
* Returns the currentPage. 00vBpsZj2;
*/ b_$1f>
publicint getCurrentPage(){ qFRdg V>8
return currentPage; 96|[}:+$&:
} >cOeiK
>`V}U*}*H
/** e`UQz$4!
* @param currentPage 8IY19>4'5J
* The currentPage to set. yOHXY&
*/ K <`>O,
F
publicvoid setCurrentPage(int currentPage){ A{,n;;
this.currentPage = currentPage; Lue|Plm[y
} 4\ $3
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/** b#Kq[}
* @return (wt+`_6
* Returns the everyPage. >w'$1tc?+F
*/ %l9$a`&
publicint getEveryPage(){
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return everyPage; mv
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} ~I_owCVZ
8<PKKDgbfd
/** mVH,HqsXa
* @param everyPage H:oQ
* The everyPage to set. SX+RBVZU
*/ #n})X,ip2
publicvoid setEveryPage(int everyPage){ 66ohmP@04Z
this.everyPage = everyPage; ^7XAw:
?
} d!{7r7ob\
:\}U9QfCw
/** #1Z7R/
* @return -l*A
* Returns the hasNextPage. \aSz2lxEHn
*/ ZCiY,;c
publicboolean getHasNextPage(){ oK Kz 4
return hasNextPage; )+~E8yK
} 9Vh_[^bR
.)PqN s:
/** Cv TwBJy1
* @param hasNextPage Gbb\h
* The hasNextPage to set. INNAYQ
*/ f]_mzF=&
publicvoid setHasNextPage(boolean hasNextPage){ w7Dt1axB
this.hasNextPage = hasNextPage; (r F?If
} d/j@_3'
5:gj&jt;)7
/** QUP|FIpZ
* @return _PB@kH#
* Returns the hasPrePage. o bGWxI%a
*/ wGXwzU
publicboolean getHasPrePage(){ wJIB$3OT
return hasPrePage; h[U7!aM
} j@P5(3r
Di.;<v#FL
/** o~~ 9!\
* @param hasPrePage \graMu}-
* The hasPrePage to set. 5H.Db
*/ i>GdRG&q
publicvoid setHasPrePage(boolean hasPrePage){ T\3 [F%?
this.hasPrePage = hasPrePage; sc xLB;
} ?y_awoBd1
8R/
*6S=&
/** 7*'@qjTos
* @return Returns the totalPage. rWr/ p^~
* yh!B!v'
*/ ks:{TA27
publicint getTotalPage(){ d.\PS9l
return totalPage; _t.FL@3e
} fOBN=y6x
T|+$@o
/** +qE']yzm!
* @param totalPage 8ui=2k(
* The totalPage to set. TG]}X\c+V|
*/ nEVbfNo0
publicvoid setTotalPage(int totalPage){ aL)Hv k:
this.totalPage = totalPage; &7][@v
} /co%:}ln
j`9Nwa
} 3H'*?|Y(#
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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 UPO^V:.R4
ysth{[<5F3
个PageUtil,负责对Page对象进行构造: )*HjRTF6G
java代码: 3ZN>9`
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jZ#UUnR%
/*Created on 2005-4-14*/ (6-y+LG
package org.flyware.util.page; Lh!z>IWjOG
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import org.apache.commons.logging.Log; sY^lQN
import org.apache.commons.logging.LogFactory; Bm<^rhJ9
9l l|JeNi
/** J0qXtr%h\
* @author Joa V/&o]b
* /s8/q2:
*/ r#I>_Utsy
publicclass PageUtil { 2fP~;\AP
9fCO7AE0#
privatestaticfinal Log logger = LogFactory.getLog <?4cWp|i
=M7PvH'"
(PageUtil.class); Mk "vvk
a
8-;
/** MLeX;He
* Use the origin page to create a new page `:3&@.{T(
* @param page {g@A>
* @param totalRecords j`Nh7+qs
* @return ITQ9(W
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*/ kYtHX~@
publicstatic Page createPage(Page page, int 25&nwz
-$m@*L
totalRecords){ Zly-\z_
return createPage(page.getEveryPage(), z+Z%H#9e
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page.getCurrentPage(), totalRecords);
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} xv&S[=Dt
oB}K[3uB:t
/** LV\ieM
* the basic page utils not including exception We\Y \*!v
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handler &/DOO ^
* @param everyPage jQs*(=ls
* @param currentPage 1W0.Ufl)
* @param totalRecords sSy$(%
* @return page >\&= [C
*/ NkoofhZ
publicstatic Page createPage(int everyPage, int W/a,.M
7y>(H<^>
currentPage, int totalRecords){ pMDH
everyPage = getEveryPage(everyPage); {70Ou}*
currentPage = getCurrentPage(currentPage); ~K%k
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int beginIndex = getBeginIndex(everyPage, 1V0sl0i4
A{1
\f*
currentPage); Ri[S<GOMii
int totalPage = getTotalPage(everyPage, e@yx}:]h
)5'rw<:="
totalRecords); ]*a@*0=
boolean hasNextPage = hasNextPage(currentPage, ,b4~!V
MyqiBGTb
totalPage); XUf7yD
boolean hasPrePage = hasPrePage(currentPage); mDlCt_h
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returnnew Page(hasPrePage, hasNextPage, /t$*W\PL@
everyPage, totalPage, e6o/q)9#
currentPage, hi0XVC95
B#Qpd7E+*
beginIndex); r:.6"VQu}
} U(P:J e
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privatestaticint getEveryPage(int everyPage){ I}rGx
return everyPage == 0 ? 10 : everyPage; h&q=I.3O|?
} 7^&lbzVbm(
wFp~
privatestaticint getCurrentPage(int currentPage){ ` %l&zwj>
return currentPage == 0 ? 1 : currentPage; 7x%S](m%
} ,}n=Z
{clCn
privatestaticint getBeginIndex(int everyPage, int K_Z+]]$#
-ywX5B
currentPage){ k+f1sV[4}
return(currentPage - 1) * everyPage; t[/\KG8
} XRtyC4f
IL2e6b
privatestaticint getTotalPage(int everyPage, int wG;}TxrLS
XNKtL]U}$
totalRecords){ g(KK9Unu
int totalPage = 0; n}VbdxlN
%-\FVKX
if(totalRecords % everyPage == 0) 48H5_9>:
totalPage = totalRecords / everyPage; loR,XW7z
else )CFk`57U
totalPage = totalRecords / everyPage + 1 ; f_~}X#._
=obt"K%n
return totalPage; PIgGXNo
} 'w'Dwqhmr
U
7EHBW
privatestaticboolean hasPrePage(int currentPage){ Bl=nj.g
return currentPage == 1 ? false : true; ,n^TN{#
} YfV"_G.ad|
@;g`+:=
privatestaticboolean hasNextPage(int currentPage, sE^ns\&QP=
=.VepX|?D
int totalPage){ E1^aAlVSD
return currentPage == totalPage || totalPage == (_s;aK
B,r5kQI4
0 ? false : true; V[4(~,9
} KSF5)CZ5
G% o7BX
5z9JhU
} 5<!o{)I
t) ;
|GJBwrL^0
7zOhyl?
'uws
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。 ,\BfmC_i
2;dM:FHLhO
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 0T7M_G'5Q
~o}moE/
;O
做法如下: 0@o;|N"i
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 <m~T>Ql1
MP6 \r
的信息,和一个结果集List: @=02
java代码: yBr$ 0$
Q~x*bMb.
37%`P\O;s
/*Created on 2005-6-13*/ >|v=Ba6R0
package com.adt.bo; p
Z0=
t^`<*H
import java.util.List; Z'voCWCd
5Xp$yX =
import org.flyware.util.page.Page; 9` OG
,G916J*XA
/** V;M3z9xd
* @author Joa l
:f9Ih
*/ 7~nIaT
publicclass Result { ['/;'NhdlY
VC/R)%@%
private Page page; hdo+Qezu:
QBg}2.
private List content; -fb1cv~N
/E=h{|
/** L#@l(8.
* The default constructor , LCH2r
*/ PpX{+^z-%
public Result(){ L-^# 02
super(); XMjI}SPG
} p=:7 atE
N{?Tm`""
/** 43UJ#rF
* The constructor using fields v]LFZI5
* fs]#/* RR
* @param page *uk\O]
* @param content wJ;9),fL
*/ J`U$b+q6
public Result(Page page, List content){ =g{_^^n
this.page = page; 4v rm&k
this.content = content; #R~">g:w
} g_3rEvf"4
O JZ!|J8?
/** pkrl@jv >
* @return Returns the content. f]@[4<N y
*/ !Ei Ze.K
publicList getContent(){ AlPL;^Y_l
return content; O^QR;<t'
} P^'>dOI0w
9+WY@du+
/** `DU'wB
* @return Returns the page. Bbn832iMUY
*/ N[|by}@n
public Page getPage(){ 5#9`ROT9
return page; eZa3K3^
} !?tu!
M<1?
m)tI
/** `R4W4h'I
* @param content |q1b8A \
* The content to set. KDNTnA1c
*/ KD[)O7hYC
public void setContent(List content){ aufcd57
this.content = content; b;&Yw-\nZ;
} bTA14&&q
$6Q2)^LJ
/** 7LyV`6{70
* @param page cOj +}Hz58
* The page to set. V^/h;/!^
*/ 0C4*F
publicvoid setPage(Page page){ IdN%f]=/
this.page = page; ":(Cpf0
} UcKWa>:Fi
} q\{;_?a
!VJT"Ds_
g/n"N>L
tA;ZW2$#
bKZAJLnd
2. 编写业务逻辑接口,并实现它(UserManager, (+]Ig> t
<uWJ>sg^6
UserManagerImpl) W2X+NacD
java代码: }[hDg6i
AR[M8RA
YV2pERl
/*Created on 2005-7-15*/ y7}~T!UyfF
package com.adt.service; p!rGPyGC
X~<>K/}u5
import net.sf.hibernate.HibernateException;
t`&s
.n^O)|Z
import org.flyware.util.page.Page; `gA5P %
ej??j<]
import com.adt.bo.Result; l#J>It\
e-T9HM&%P
/** fu7[8R"{
* @author Joa ;#Crh}~
*/ $7k04e@]
publicinterface UserManager { QVA!z##
y+~Aw"J}
public Result listUser(Page page)throws /fcwz5~
#!F8n` C-
HibernateException; s3fGX|;
Xf'
} M#22Zfxq
%Tm'aY"
X~/9Vd g
}~0{1&
[;kj,j
java代码: !UPAEA
R.n`R|NOd
5Dh&ez`oR'
/*Created on 2005-7-15*/ $(<*pU
package com.adt.service.impl; -^SD6l$
s$=B~l
import java.util.List;
fjeE.
E rRMiT
import net.sf.hibernate.HibernateException; a}I z
WY ^K7U
import org.flyware.util.page.Page; BfO}4
import org.flyware.util.page.PageUtil; :Q%yW%St$
)="g?E3
import com.adt.bo.Result; 9DocId.
import com.adt.dao.UserDAO; h?O%XnD
import com.adt.exception.ObjectNotFoundException; }e;p8)]Wl
import com.adt.service.UserManager; nh_xbo5L[
9ixnf=$Jp
/** G#=b6DB
* @author Joa S3[oA&
*/ L:]; [xa%
publicclass UserManagerImpl implements UserManager { sjgxx7
Q0oDl8~
private UserDAO userDAO; DW;.R<8
)7 BNzj"~
/** !&<Wc^PG
* @param userDAO The userDAO to set. ?2
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*/ J5r
L7
publicvoid setUserDAO(UserDAO userDAO){ #on fac- 3
this.userDAO = userDAO; 9cHNwgD>v
} Y{\2wU!Isn
s?gXp{O?X
/* (non-Javadoc) +r34\mAO
* @see com.adt.service.UserManager#listUser aG&kl O>m
Z_TbM^N
(org.flyware.util.page.Page) @eD2<e
*/ W71#NjM2Z
public Result listUser(Page page)throws ;R-Q,aCM}
8CHf. SXh
HibernateException, ObjectNotFoundException { 'J<zVD}0
int totalRecords = userDAO.getUserCount(); "\P~Re"EH
if(totalRecords == 0) Ffqn|}gb
throw new ObjectNotFoundException vskM;
? F:C!_
("userNotExist"); 6(RqR
page = PageUtil.createPage(page, totalRecords); n$VPh/
List users = userDAO.getUserByPage(page); enO=-#
returnnew Result(page, users); Vf* B1Zb
} d(cYtM,P
)fcpE,g'
} [;\<
2 =H
r4qV}-E
UM;bVf?
Xv;ZA a
D_`)T;<Sp
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 >w'?DV>u|
xo@/k
询,接下来编写UserDAO的代码: {hp@j#
3. UserDAO 和 UserDAOImpl: S+=@d\S}"
java代码: D"><S<C\C
&rE l
oz7udY=]0
/*Created on 2005-7-15*/ OTbjZ(
package com.adt.dao; {d5ur@G1
G7#~=W
2M
import java.util.List; xn#I7]]G
-)c"cgx.
import org.flyware.util.page.Page; x[<#mt
^.aEKr
import net.sf.hibernate.HibernateException; oHGf |
*v-xC5L1\
/** kT3;%D^
* @author Joa iY`7\/H!L
*/ =(uy':Dbn*
publicinterface UserDAO extends BaseDAO { K>E!W!-PJ
J};,%q_
publicList getUserByName(String name)throws ;R>42
qYF
|zegnq~
HibernateException; !)1Zp*
rs)aEmvC
publicint getUserCount()throws HibernateException; xH.q
krT!AfeV
publicList getUserByPage(Page page)throws {.[,ee-)9
v}t:}M<;
HibernateException; "h|0]y^2
E.*OA y
} @G&xq"Fg7
04LVa|Y@U
s.Ic3ITd,
15yV4wHr
F973U
java代码: <qZ+U4@I)
_z6u^#Si
JN|#
/*Created on 2005-7-15*/ C)dYAq3,8
package com.adt.dao.impl; ;&:Et
n/|`Dz.
import java.util.List; =Qq^=3@h
?DTP-#5Ba
import org.flyware.util.page.Page; h1d0{
bao5^t}
import net.sf.hibernate.HibernateException; JHOBg{Wg
import net.sf.hibernate.Query; G~j<I/)"
omU)hFvyS
import com.adt.dao.UserDAO; 6>^k9cJp
m.X+sP-e
/** jtJ8r5j 1
* @author Joa !q1^X% a
*/ fu;B ?mIn
public class UserDAOImpl extends BaseDAOHibernateImpl -s84/E4Y*
/1@m#ZxA:
implements UserDAO { ?a_q!,8:
DFH6.0UW
/* (non-Javadoc) (9lx5
* @see com.adt.dao.UserDAO#getUserByName nf^k3QS\
f@X*Tlx^|
(java.lang.String) |1 6v4 R
*/ L*Cf&c`8r
publicList getUserByName(String name)throws qf {B
Z-V%lRQ=b
HibernateException { ZX}"
String querySentence = "FROM user in class )4C6+63OD&
-C]a2
com.adt.po.User WHERE user.name=:name"; ~#Mx&mZ
Query query = getSession().createQuery U~c;W@T
xL"o)]a=
(querySentence); Q2PwO;E.`C
query.setParameter("name", name); S}I=i>QB
return query.list(); hS/'b$#
} 1Ac1CsK*
g0$k_
/* (non-Javadoc) f@g
* @see com.adt.dao.UserDAO#getUserCount() t9l7
% +y
*/ VAzJclB
publicint getUserCount()throws HibernateException { i`spM<iR.
int count = 0; SZ){1Hu
String querySentence = "SELECT count(*) FROM @=1``z#
}Elce}
user in class com.adt.po.User"; eF\C?4
Query query = getSession().createQuery J4X35H=Z
jzw?V9Ijb
(querySentence); U /Fomu
count = ((Integer)query.iterate().next Ji=iq=S7
r $2
()).intValue(); AXI:h"so
return count; oa7Hx<Y
} MPc=cLv
B\yq%m
/* (non-Javadoc) znRhQ+8;!
* @see com.adt.dao.UserDAO#getUserByPage g>CQO,s;w
M*uG`Eo&
(org.flyware.util.page.Page) {P+[CO
*/ Puh&F< B
publicList getUserByPage(Page page)throws ?Ea"%z*c5
u{z{3fW_
HibernateException { #+\G-
=-
String querySentence = "FROM user in class 9mm(?O~'p
`7ZJB$7D|*
com.adt.po.User"; '& :"/4@)
Query query = getSession().createQuery _\[G7
,oil}N(
(querySentence); /L^dHI]Q
query.setFirstResult(page.getBeginIndex()) 2N]s}/l
.setMaxResults(page.getEveryPage()); 8m0sEV>
return query.list(); >S]')O$c
} ;{20Heuz
tTt~W5lo
} TQH#sx
B8Z66#EQ
}lVUa{ubf
E(#2/E6
e:<>
Yq+
至此,一个完整的分页程序完成。前台的只需要调用 uUs>/+
.EwK>ro4
userManager.listUser(page)即可得到一个Page对象和结果集对象 H'>
W
aU_Z/{0
的综合体,而传入的参数page对象则可以由前台传入,如果用 i/z7a%$
],|B4\b ;
webwork,甚至可以直接在配置文件中指定。 ^eii
4
j C?
下面给出一个webwork调用示例: (0S7
java代码: rJ>8|K[kt
f6) H!SI
*Yw6UCO
/*Created on 2005-6-17*/ R#M).2::
package com.adt.action.user; wxxC&!
F^-4Pyq@
import java.util.List; jK53-tF~I
;*p}~#2
import org.apache.commons.logging.Log; Q{60^vg
import org.apache.commons.logging.LogFactory; 7j8_O@_
import org.flyware.util.page.Page; `R RORzXoS
P9vROzXK
import com.adt.bo.Result; [G*mQ@G9
import com.adt.service.UserService; ;U&VPIX$
import com.opensymphony.xwork.Action; rv:O|wZ
e`^j_VnEH
/** |~Iw
* @author Joa FReK
*/ T*m_rDDt
publicclass ListUser implementsAction{ ^(R
gSMuT`
om6R/K
privatestaticfinal Log logger = LogFactory.getLog dQ]j
r.
_NFJm(X.
(ListUser.class); l<+k[@Vox
3Daq5(fLP
private UserService userService; ~4 ab\hq
:|Cf$2k7
private Page page; 9tO_hhEQ@
f&'md
privateList users; -5K/ cK
2X`M&)"X
/* Yi`.zm
* (non-Javadoc) tN~{Mt$-W
* "2J;~
* @see com.opensymphony.xwork.Action#execute() szHUHW~;J
*/ 4~4Hst#^
publicString execute()throwsException{ F<[8!^l(z
Result result = userService.listUser(page); K9R[
oB]b
page = result.getPage(); bu-
RU(%
users = result.getContent(); .@'Vz;&mQ
return SUCCESS; m\yO/9{h1
} xlAaIo)T
`F#KXk
/** H@zpw1fH+
* @return Returns the page. U!4 ^;
*/ /_P`xm+=AC
public Page getPage(){ 0U'r ia:$
return page; <,{v>vlw
} R[QE:#hT
C;` fOCz^
/** SDkN
* @return Returns the users. IWkBq]Y
*/ })B)-8
publicList getUsers(){ ^:BRbp37i
return users; \MU4"sXw
} PA E)3
&N EzKf
/** JsV#:
* @param page S<TfvQ\,"@
* The page to set. 4?Io@[7A)
*/ T(6S~;,Z
publicvoid setPage(Page page){ ="`y<J P
this.page = page; X^ovP'c2
} VaB7)r
0pQ>V)
/** ,Gfnf%H\8>
* @param users p:
o*=
* The users to set. ;(V=disU/
*/ m#Cp.|>kP4
publicvoid setUsers(List users){ *;Vq0a!
this.users = users; m +gVGK
} cMj<k8.{
x\*5A,w{c]
/** O1z>A
* @param userService =c|Bu^(Ctw
* The userService to set. -&c@c@dC
*/ {PU[MHZF
publicvoid setUserService(UserService userService){ ]n{2cPx5d
this.userService = userService; xsfq[}eH<
} .D :v0Zm}m
} tQ/U'Ap&
er53?z7zP.
.}tL:^'~o
HV}NT~
Y !`H_Qo
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, ;j$84o{
*q^'%'
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 !MbRI
'
|4XyU=
么只需要: H Q2-20
java代码: VAq:q8(K
RR"#z'zQ
M?,;TJ7Gd
<?xml version="1.0"?> ;,viE~n
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork :A[ Gtc(_
(nBsf1l
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ^3el-dZ
O&}0 7(
1.0.dtd"> VR'w$mp
62W3W1: W
<xwork> n1H*][CK
lB-Njr
<package name="user" extends="webwork- })J]D~!p
wtZe\h
interceptors"> F*a+&% Q
t<e?f{Q5
<!-- The default interceptor stack name ]|-y[iu
@gZ%>qe
--> Y$(G)Fs
<default-interceptor-ref w'UP#vT5&
R)#"Ab Z'
name="myDefaultWebStack"/> _8bqk\m+
P?bdjU#_n`
<action name="listUser" 5f1yszd
zP5H TEz
class="com.adt.action.user.ListUser"> rIu>JyC"p
<param \\[P^ tsF
Ar|_UV>Zf
name="page.everyPage">10</param> &R 0BuFL8
<result QII>XJ9
5bgx;z9
name="success">/user/user_list.jsp</result> l!`m}$
</action> c0tv!PSw
uz%rWN`{
</package> ?f a/}|T
towQoqv
</xwork> f5'+F-`N
#*~#t4S-
^D!UF(H
akaQ6DIdG
\;Ii(3+v;
J&lQ,T!?B
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 T'w=v-(J
oqG
0 @@
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。 <}|+2f233+
Wt_@ vs@.O
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 `TAhW
eQMY3/#
W4Zi?@L>'
c: _l+CgeH
{uq
我写的一个用于分页的类,用了泛型了,hoho T@X!vCjf6
qg+8i9Y!
java代码: qF>}"m
*r[PZ{D+
;X\,-pjv
package com.intokr.util; SC'fT!
1;SWfKU?.
import java.util.List; c\n\gQ:LQ
`2{x8A
/** tM~R?9OaJ
* 用于分页的类<br> ,*Sj7qb#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> y+@7k3"
* =T!M`
* @version 0.01 S?;&vs9j
* @author cheng 9^ )=N=wV
*/ e;,D!
public class Paginator<E> { 0&Zm3(}
privateint count = 0; // 总记录数 o4tQ9X=}
privateint p = 1; // 页编号 )
_"`{2
privateint num = 20; // 每页的记录数 \
VJ3
privateList<E> results = null; // 结果 )~rN{W<s`H
GBN^ *I
/** ~fEgrF d
* 结果总数 c}lUP(Ss
*/ F?TAyD*
publicint getCount(){ 5_{C \S`T
return count; @99@do|C
} ~p^6
:+; UW
\
publicvoid setCount(int count){ |R DPx6!V
this.count = count; W$
M4#
} #\Lt0
2B5Z0<
/** m%l\EE
* 本结果所在的页码,从1开始 ,{7Z OzA
* 8h}o5B
* @return Returns the pageNo. 7@5}WNr
*/ 9tWu>keu
publicint getP(){ iq=<LOx
return p; L3,p8-d9Z
} Beqzw0
BA53
/** |I6\_K.=L
* if(p<=0) p=1 WM~@/J
* /{^Qup
* @param p WL+I)n8~
*/ pvD\E
publicvoid setP(int p){ SVo:%mX
if(p <= 0) G)G5eXXX
p = 1; UOi8>;k`
this.p = p; "}Vow^vb
} >d&B:
N!{('po
/** 8:TN,p
* 每页记录数量 D `c
YQ-
*/ +g>)Bur
publicint getNum(){ w/#k.YE
return num; UW_fn
} ~A(fn:d
>S,yqKp37~
/** p<: bPw
* if(num<1) num=1 7X*$Fu<
*/ sFuB[
JJ}
publicvoid setNum(int num){ V'K1kYb
if(num < 1) :=C-P7
num = 1; <!EdND =
this.num = num; Z.ky=vCt
} TFjb1a,)
IC"bg<L,*
/** l03{
ezJk[
* 获得总页数 bj=kqO;*O
*/ <k+dJ=f
publicint getPageNum(){ KLrxlD4\
return(count - 1) / num + 1;
^"STM'Zh
} ZF!cXo7d
w9Bbvr6
/** FCgr
* 获得本页的开始编号,为 (p-1)*num+1 7j| ^ZuI+
*/ * G!C 'w\$
publicint getStart(){ XvETys@d
return(p - 1) * num + 1; SfLZVB
} "N>~]
Zn0e#n
/** F !g>fIg
* @return Returns the results. o'O;69D]tX
*/ LVP2jTz
publicList<E> getResults(){ 38#BINhBt
return results; MH7 n@.t
} )7j jfD\
#q#C_"
public void setResults(List<E> results){ ROsR;C0!
this.results = results; H]As2$[
} 8w/$!9[
W;!OxOWZJ
public String toString(){ wrI66R}@
StringBuilder buff = new StringBuilder uj;tmK>;
cBZ$$$v\#
(); pY]T32
buff.append("{"); 9K,PT.c
buff.append("count:").append(count); kCRfO}wt3
buff.append(",p:").append(p); (dmLEt
buff.append(",nump:").append(num); A:!_ &