Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 T2}I,{U
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 7~eo^/PbS
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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 n@5pS3qZ
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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 )~O{jd
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分页支持类: (OYR, [*
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java代码: YurK@Tq7
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package com.javaeye.common.util; Xe*@`&nv@
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import java.util.List; L1Fn;nR
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publicclass PaginationSupport { 8:L%-
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publicfinalstaticint PAGESIZE = 30; +sE8 1B
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privateint pageSize = PAGESIZE; y*\ M7}](
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privateList items; \ H<'W"
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privateint totalCount; _"a(vfl#
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privateint[] indexes = newint[0]; gO4J[_
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privateint startIndex = 0; p4W->AVv$
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public PaginationSupport(List items, int p."pI Bd
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totalCount){ Z=R>7~H
setPageSize(PAGESIZE); (~}yt .7K
setTotalCount(totalCount); =d7 lrx+z
setItems(items); zBB4lC{q
setStartIndex(0); y$*Tbzp
} &>@nW!n
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public PaginationSupport(List items, int !F;W#Gc
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totalCount, int startIndex){ nrwb6wj
setPageSize(PAGESIZE); X LA
setTotalCount(totalCount); *u
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setItems(items); 6peO9]Zy
setStartIndex(startIndex); AvEJX0"\df
} JF%+T yMe
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public PaginationSupport(List items, int /qo. Z
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totalCount, int pageSize, int startIndex){ <R*.T)Z 1
setPageSize(pageSize); ~Rk6@&ZS}
setTotalCount(totalCount); &{x5 |$SD
setItems(items); #?!)-Q%
setStartIndex(startIndex); x~j%
} lx U}HM
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publicList getItems(){ sUfH1w)0
return items; !7AW_l9`i
} <|hvH
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publicvoid setItems(List items){ 6;I&{9
this.items = items; pL.r
9T.
} S<88>|&n]
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publicint getPageSize(){ *@cXBav/<
return pageSize; t \DS}3pv
} V2i*PK
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publicvoid setPageSize(int pageSize){ rbO9NRg>
this.pageSize = pageSize; yew9bn0a=
} /]F3t]FlC
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publicint getTotalCount(){ '2uQ
return totalCount; `-]*Qb+
} f@[q# }6
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publicvoid setTotalCount(int totalCount){ B6MMn.
if(totalCount > 0){ ysGK5kFz
this.totalCount = totalCount; asj^K|.z
int count = totalCount / -?2ThvT
4}W*,&_
pageSize; #&1mc_`/
if(totalCount % pageSize > 0) 4@/[aFH
count++; h[ba$S,T
indexes = newint[count]; z1T.\mzfX
for(int i = 0; i < count; i++){ $w)yQ %
indexes = pageSize * 5mnIQ~psR
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} ?bmP<(N5/
}else{ T.`E DluG
this.totalCount = 0; .N5}JUj
} c:>&Bg&,6T
} u~bk~3.I
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publicint[] getIndexes(){ vtCt6M
return indexes; \n6#D7OV
} 9p+DAs{i
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publicvoid setIndexes(int[] indexes){ ?\(E+6tpP
this.indexes = indexes; jXSo{
} c,!Ijn\;(
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publicint getStartIndex(){ pu0IhDMn
return startIndex; U$# ?Lw
} TlQ#0_as[
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publicvoid setStartIndex(int startIndex){ ?`uY*+u
if(totalCount <= 0) {tOu+zy
this.startIndex = 0; R',Q)<
elseif(startIndex >= totalCount) ,=Xr'7w,
this.startIndex = indexes *6df|q
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[indexes.length - 1]; k_
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elseif(startIndex < 0) Ra%RcUf~sh
this.startIndex = 0; SBzJQt@Hs
else{ W[AX?
this.startIndex = indexes 8jMw7ti
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[startIndex / pageSize]; O B_g:T
} q}*(rR9/Br
} jdK~]eld=
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publicint getNextIndex(){ 8uP,#D<wZ
int nextIndex = getStartIndex() + GXr9J rs.e
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pageSize; 4;<?ec(dc
if(nextIndex >= totalCount) W.r0W2))(
return getStartIndex(); z4HIDb
else eY-W5TgU
return nextIndex; Xjw>Qws
} &-:ZM0Fl
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publicint getPreviousIndex(){ Mi%i_T^i
int previousIndex = getStartIndex() - r?nvJHP
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pageSize; X#EMmB!
if(previousIndex < 0) T&oY:1D,g
return0; [ %cW ?@
else s{(aW5$!s
return previousIndex; cV\(Z6u
} 3=RV Jb
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} YiJnh47
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^
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抽象业务类 JF!JY( U,
java代码: Ew5(U`]
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/** umaF}}-Q{
* Created on 2005-7-12 ]i(tou-[i
*/ '-oS=OrZ
package com.javaeye.common.business; :.e`w#$7
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import java.io.Serializable; 9]< p
import java.util.List; i,r O3Jn
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import org.hibernate.Criteria; VCSHq&p8
import org.hibernate.HibernateException; {F6>XuS=u
import org.hibernate.Session; {Fs}8\ z
import org.hibernate.criterion.DetachedCriteria; 2&MIt(\-
import org.hibernate.criterion.Projections; Y,w'Op
import 'r~,~AI
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org.springframework.orm.hibernate3.HibernateCallback; 8n+&tBq1
import \3JZ=/
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org.springframework.orm.hibernate3.support.HibernateDaoS %X7R_>.
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upport; d[E~}Dq3#
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import com.javaeye.common.util.PaginationSupport; $M{MOehZ
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public abstract class AbstractManager extends tS!FnQg4
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HibernateDaoSupport { _0N=~`'
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privateboolean cacheQueries = false; \X.CYkgK
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privateString queryCacheRegion; ZG[P?fM
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publicvoid setCacheQueries(boolean v%v(-, _q
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cacheQueries){ 5b> -t#N,
this.cacheQueries = cacheQueries; Oxo?\
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} fFDI qX
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publicvoid setQueryCacheRegion(String `B6*wE-|
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queryCacheRegion){ ,I6jfXI4
this.queryCacheRegion = ~e*3_l>9
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queryCacheRegion; x\PZ.o
} <7'`N\a
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publicvoid save(finalObject entity){ FvYgp bEZ
getHibernateTemplate().save(entity); URU,&gy=
} 0U|t@&q
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publicvoid persist(finalObject entity){ HYcLXh vgu
getHibernateTemplate().save(entity); G>Fk
)
} \WS2g"(
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publicvoid update(finalObject entity){ ffoL]u\
getHibernateTemplate().update(entity); <A|X4;
} YnM&t
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publicvoid delete(finalObject entity){ X$*MxMNs
getHibernateTemplate().delete(entity); Pq\
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} kY>jp@wV
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publicObject load(finalClass entity, w>#{Nl7gz
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finalSerializable id){ ;f;A"
return getHibernateTemplate().load F1_s%&
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(entity, id); (V&5EO8)
} o>|&k]W/
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publicObject get(finalClass entity, b a5,?FVI~
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finalSerializable id){ /{1s U}k-
return getHibernateTemplate().get yyPQ^{zD
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(entity, id); &10l80vj
} M3XG s|gw
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publicList findAll(finalClass entity){ w8=&rzr8
return getHibernateTemplate().find("from nm"]q`(K
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" + entity.getName()); ),{v
} F}1h
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publicList findByNamedQuery(finalString @jL](Mq|]
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namedQuery){ B":9C'tip
return getHibernateTemplate 26M:D&| ZB
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().findByNamedQuery(namedQuery); ^b M\:z"M
} Borr
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publicList findByNamedQuery(finalString query, FOPfob[
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finalObject parameter){ * 'eE[/K
return getHibernateTemplate &}'FC7}
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().findByNamedQuery(query, parameter); #|PPkg%v<
} 7MWd(n-
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publicList findByNamedQuery(finalString query, 4nsc`Hu
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finalObject[] parameters){ 1.9bU/X
return getHibernateTemplate GLO%>&
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().findByNamedQuery(query, parameters);
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} s5bqS'%
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publicList find(finalString query){ O]4v\~@-j
return getHibernateTemplate().find X<%`
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(query); Vu`5/QDq
} 1Clid\T,o
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publicList find(finalString query, finalObject V`
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parameter){ zqHG2:MN"
return getHibernateTemplate().find >jU25"XI[
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(query, parameter); a8WWFAC[
} }/w]+f*
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public PaginationSupport findPageByCriteria d*YVk{s7V
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(final DetachedCriteria detachedCriteria){ -uKTEG[
return findPageByCriteria |}7!'f\M
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); nt&"?
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} 57fl<IM
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public PaginationSupport findPageByCriteria jn
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(final DetachedCriteria detachedCriteria, finalint lfAiW;giJ
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startIndex){ $`A{-0=x\U
return findPageByCriteria S$O5jX 0
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(detachedCriteria, PaginationSupport.PAGESIZE, 7|HIl=
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startIndex); jY2mn" .N
} {#.<hPXn
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public PaginationSupport findPageByCriteria "Xg~1)%
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(final DetachedCriteria detachedCriteria, finalint 6b7c9n Z
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pageSize, *@ {
finalint startIndex){ zviTGhA
return(PaginationSupport) ECyG$j0
_l"=#i@L
getHibernateTemplate().execute(new HibernateCallback(){ rB|1<jR
publicObject doInHibernate 28LBvJVq@
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(Session session)throws HibernateException { /-knqv
Criteria criteria = 6HguZ_jC
ih|;H:"^
detachedCriteria.getExecutableCriteria(session); DfU]+;AE
int totalCount = x5Ue"RMl+
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((Integer) criteria.setProjection(Projections.rowCount Z2L7US-
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()).uniqueResult()).intValue(); v.-r %j{I
criteria.setProjection D^QL.Du,
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(null); .kU}x3m
List items = U(PW$\l
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criteria.setFirstResult(startIndex).setMaxResults A0>r]<y
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(pageSize).list(); c1q;
PaginationSupport ps = Gshy$'_e
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new PaginationSupport(items, totalCount, pageSize, 3-=AmRxW't
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startIndex); %Z+**>1J
return ps; PqIskv+
} *8J0yv
}, true); y^e3Gyk
} ]%ewxF
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public List findAllByCriteria(final '`YZJ
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DetachedCriteria detachedCriteria){ ^9`|QF
return(List) getHibernateTemplate o[1#)&
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().execute(new HibernateCallback(){ gKY6S?
publicObject doInHibernate yM}3u4FG
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(Session session)throws HibernateException { ]61Si~Z
Criteria criteria = _R(9O?;q
Yi]`"\
detachedCriteria.getExecutableCriteria(session); 5A$,'%d
return criteria.list(); OTGy[jY"
} Zb&pH~ 7
}, true); Go!{@xx>
} lX-i <0`
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public int getCountByCriteria(final qDTdYf
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DetachedCriteria detachedCriteria){ fJP *RVz
Integer count = (Integer) |VzXcV-"8)
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getHibernateTemplate().execute(new HibernateCallback(){ [mv!r-=
publicObject doInHibernate c:52pYf+
mlCBstt{
(Session session)throws HibernateException { L
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Criteria criteria = d``wx}#Uk
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detachedCriteria.getExecutableCriteria(session); _-sFJi8B
return QFnpp\K
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criteria.setProjection(Projections.rowCount )7]yzc
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()).uniqueResult(); /\_n5XI1
} +I-BqA9
}, true); 6:L2oW 6}{
return count.intValue(); 1hlU
6=Y
} MRw4?HqB
} ahIDKvJ4
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用户在web层构造查询条件detachedCriteria,和可选的 Mo<q(_ZeRP
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 \m~p;B
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PaginationSupport的实例ps。 6-uLK'E
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ps.getItems()得到已分页好的结果集 $qr6LIKGw
ps.getIndexes()得到分页索引的数组 x;sc?5_`
ps.getTotalCount()得到总结果数 |`?&
ps.getStartIndex()当前分页索引 %$kd`Rl}
ps.getNextIndex()下一页索引 }vh4ix
ps.getPreviousIndex()上一页索引 q*4U2_^.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 122s7A
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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 ]jm:VF]4
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一下代码重构了。 ^H7xFd|>
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我把原本我的做法也提供出来供大家讨论吧: 7)Vbp--b#
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首先,为了实现分页查询,我封装了一个Page类: i\l}M]Z#
java代码: <G|i5/|7
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/*Created on 2005-4-14*/ ,Pcg+^A
package org.flyware.util.page; [FrLxU
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/** V2`Ud[
* @author Joa uDXV@;6<
* 4bp})>}jB
*/ QK#wsw
publicclass Page { nw%9Qw
p/RT*?<
/** imply if the page has previous page */ OA=~i/n~
privateboolean hasPrePage; qljsoDG
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/** imply if the page has next page */ F[$cE
privateboolean hasNextPage; Osm))Ua(
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/** the number of every page */ nD XEm6|e
privateint everyPage; qbeUc5`1
NU?<bIQ
/** the total page number */ p%&$%yz$
privateint totalPage; {+7FBdxVB
}.&;NgZS
/** the number of current page */ 6
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privateint currentPage; c`p'5qz
<$zhNu~
/** the begin index of the records by the current 7L6L{~8
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query */ CxjB9#
privateint beginIndex; MjQju@
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/** The default constructor */ /z4c>)fV
public Page(){ Y8]@y0(
dd<l;4(
} 72"H#dy%U
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/** construct the page by everyPage |u^S}"@3sU
* @param everyPage :o{,F7(P
* */ Gj-nTN
public Page(int everyPage){ e%L[bGW'
this.everyPage = everyPage; ;*<R~HJt
} uOeal^uS
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/** The whole constructor */ @-Ql6k
public Page(boolean hasPrePage, boolean hasNextPage, -qDqJ62mC
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1<73uR&b%
int everyPage, int totalPage, >8kXa.)84
int currentPage, int beginIndex){ @WS77d~S
this.hasPrePage = hasPrePage; 86 e13MF
this.hasNextPage = hasNextPage; ;J TY#)Bh
this.everyPage = everyPage; >~rlnRX
this.totalPage = totalPage; ERIMz,
this.currentPage = currentPage; th[v"qD9G
this.beginIndex = beginIndex; k:run2K
} kl.; E{PL
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/** {FI*oO1A~
* @return [UI>SN
* Returns the beginIndex. cI\[)5&
*/ n.2:fk
publicint getBeginIndex(){ j\~,Gtn>Z
return beginIndex; =FhP$r*
} \8QOZjy
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/** czD"mI!
* @param beginIndex 2I }p X9
* The beginIndex to set. ,7Hyrx`
*/ <n]P D;.4
publicvoid setBeginIndex(int beginIndex){ XyE$0i~t
this.beginIndex = beginIndex; ^ZQMRNP{r
} *}lLV.+A
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/** }#H,oy;Dz
* @return >lUPOc
* Returns the currentPage. mXp#6'a
*/ X'PZCg W
publicint getCurrentPage(){ S
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return currentPage; [m0X kvd
} 3<
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/** mW%8`$rVEO
* @param currentPage F6[F~^9D
* The currentPage to set. uW!XzX['
*/ MmjZq
publicvoid setCurrentPage(int currentPage){ lxL.ztL
this.currentPage = currentPage; #Z2'Y[@.
} ?QT6q]|d0+
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/** '?veMX
* @return w/nohZF6H
* Returns the everyPage. %o%V4K*
*/ T{C;bf:Q
publicint getEveryPage(){ 3 Vc}Q'&Y
return everyPage; rV%T+!n%c
} r3g^0|)
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/** FHr)xqo=~
* @param everyPage /o;L,mcx*
* The everyPage to set. js81@WX!c
*/ H
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publicvoid setEveryPage(int everyPage){ G9Uc
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this.everyPage = everyPage; Z\CvaX
} Ie.
on )
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/** (O0 Ry2uk
* @return |z=`Ur@)
* Returns the hasNextPage. ct3i^,i
*/ AuXUD9-
publicboolean getHasNextPage(){ z.cDbkf}
return hasNextPage; H 1kI+YJ@
} Yn~fnI{
c{/R?<
/** eW(pP>@k,
* @param hasNextPage 5 qfvHQ ~M
* The hasNextPage to set. imYfRi=$
*/ H<_Tn$<zH.
publicvoid setHasNextPage(boolean hasNextPage){ 3s!6rT_=)d
this.hasNextPage = hasNextPage; k=mQG~
} bu _ @>`S
E#,"C`&*
/** ^}-l["u`
* @return cRnDAn#42
* Returns the hasPrePage. KNAvLcg
*/ dRron_'
publicboolean getHasPrePage(){ NlEyT9
return hasPrePage; PF`uwx@zH
}
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/** &IUA[{o~e
* @param hasPrePage ~][~aEat;V
* The hasPrePage to set. AhF@
*/ <J;O$S
publicvoid setHasPrePage(boolean hasPrePage){ 3$!QP
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this.hasPrePage = hasPrePage; #Zm`*s`
} PK:Lv15"r
eVf D&&@
/** y]jx-wc3O
* @return Returns the totalPage. L[2qCxB'^
* z[c8W@OJ
*/ ta)gOc)r
R
publicint getTotalPage(){ PuP"(
M
return totalPage; l[T-Ak
} b\}a
V|'@D#\
/** "mJo<i}
* @param totalPage l ubsL I
* The totalPage to set. #EzhtuHxn
*/ %]LoR$|Y
publicvoid setTotalPage(int totalPage){ L>14=Pr^(
this.totalPage = totalPage; Z2]0brV
} mKe6rEUs|
=T[P
} daKZ*B|
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s=jmvvs_V}
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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 H2jypVs$2
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个PageUtil,负责对Page对象进行构造: Dr.eos4 ~
java代码: yf:0u_&]
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/*Created on 2005-4-14*/ jv~#'=T'
package org.flyware.util.page; F `:Q
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import org.apache.commons.logging.Log; Sn-#Y(>]o0
import org.apache.commons.logging.LogFactory; t`JT
=cl#aS}e8
/** P;I,f
* @author Joa #!Cg$6%x9
* 3 ~P$p<
*/ g&g:HH:
publicclass PageUtil { .@&FJYkLYi
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privatestaticfinal Log logger = LogFactory.getLog ]x
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(PageUtil.class); pA .orx
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/** !hQ-i3?qm
* Use the origin page to create a new page GhfhR^P
* @param page wetu.aMp
* @param totalRecords gaXo)o S
* @return i`@cVYsL
*/ Lmjd,t
publicstatic Page createPage(Page page, int Gk5'|s
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totalRecords){ e2=}qE7
return createPage(page.getEveryPage(), jF;<9-m&
jj&G[-"bv
page.getCurrentPage(), totalRecords); *I?-A(e
} -"xAeI1+
hXI[FICQU{
/** %@:>hQ2;
* the basic page utils not including exception X40gJV<
`S((F|Ty=;
handler l)$mpMgAD
* @param everyPage [Z/P[370
* @param currentPage h's[)
t
* @param totalRecords xCL)<8[R,}
* @return page =M
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*/ b$Hbo;_
publicstatic Page createPage(int everyPage, int KN_n :`cH{
g=D]=&H
currentPage, int totalRecords){ M{p6&eg
everyPage = getEveryPage(everyPage); ! =21K0~t#
currentPage = getCurrentPage(currentPage); ^r}Uu~A>
int beginIndex = getBeginIndex(everyPage, ek)rsxf1A
TSFrv8L
currentPage); BMAWjEr
int totalPage = getTotalPage(everyPage, lJAzG,f
`P\H{
totalRecords); `{YOl\d_
boolean hasNextPage = hasNextPage(currentPage, X#axCDM-
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totalPage); TQeIAy
boolean hasPrePage = hasPrePage(currentPage); ;VCV%=W<
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returnnew Page(hasPrePage, hasNextPage, E*)A!2rlK
everyPage, totalPage, _\4r~=`HQ
currentPage, XzV>q~I3|E
{0j,U\ kb
beginIndex); X{xkXg8h
} ,Z|O y|+'
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privatestaticint getEveryPage(int everyPage){ %tkqWK:
return everyPage == 0 ? 10 : everyPage; qX5]\nX&G
} Pq~#SxA~
W\<OCD%X
privatestaticint getCurrentPage(int currentPage){ d3E N0e+^
return currentPage == 0 ? 1 : currentPage; Onqapm0
} =KR^0<2r
k7:ISjJ
privatestaticint getBeginIndex(int everyPage, int ,?U(PEO\f
+q2\3REzx
currentPage){ MV<)qa T
return(currentPage - 1) * everyPage; VKXi*F9
} 7202N?a
{
r8R7@S2V'
privatestaticint getTotalPage(int everyPage, int n)cc\JPQ
71Q`B#t0'Z
totalRecords){ mn1!A`$
int totalPage = 0; t`&mszd~T
6R m d t
if(totalRecords % everyPage == 0) fC^d@4ha
totalPage = totalRecords / everyPage; ajRht +{
else Q>yj<DR
totalPage = totalRecords / everyPage + 1 ; m?Jnb\0
=WCE "X
return totalPage; z1RHdu0;z
} )e[q%%ks
Wsd_RT }ww
privatestaticboolean hasPrePage(int currentPage){ X%!?\3S
return currentPage == 1 ? false : true; b%F'Ou~
} fm^tU0DY
n}%_H4t
privatestaticboolean hasNextPage(int currentPage, x2~fc
r_ 9"^Er
int totalPage){ 'lC=k7@x
return currentPage == totalPage || totalPage == (
K-7z
P[`>*C\9c
0 ? false : true; p^{yA"MQ
} N<(rP1)`v
/q]fG
Yo5ged]i
} N+R{&v7=F%
lh0G/8+C
brE%/%!e
!`U #Pjp.
,9:v2=C_
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。 RionKiN
4wS!g10 }
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 '6WZi|(a
<1sUK4nQ,
做法如下: Pmuk !V}f
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 R $/q=*k
Nde1`W]:
的信息,和一个结果集List: 50S*_4R
java代码: H6#SP~V
^s8JW" H
Hb!A\;>
/*Created on 2005-6-13*/ Q Na*Y@i
package com.adt.bo; R8% u9o
y(Pv1=e
import java.util.List; k3
' 5Ei
\>/AF<2"
import org.flyware.util.page.Page; _}`y3"CD7
{yBd{x<>/
/** -RThd"
* @author Joa E&vCzQ
*/ CZv^,O(M?2
publicclass Result { "g!/^A!!
9zehwl]~
private Page page; kx0w?A8-
/{ 8 .Jcx$
private List content; )]}68}9
Df$Yn
/** z_&T>ME
* The default constructor C5^N)-]"
*/ Mm^6*L]
public Result(){ 1kc{`oL
super(); n
u>6UjV
} Iak06E
xUs1-O1i
/** H#`&!p
* The constructor using fields ~bjT,i
* y3 S T"U
* @param page |R Qa.^.
* @param content .w~L0(
*/ 1 rmN)
public Result(Page page, List content){ sMw"C~XL
this.page = page; }Oy/F
this.content = content; >F!X'#Iv
} `O,"mm^@U
0c#|LF_
/** X`}4=>
* @return Returns the content. VS<w:{*
*/ SQ`ec95',
publicList getContent(){ 6<Zk%[7t
return content; ukXKUYNm8
} YP}r15P
)%?SWuS?N
/** u z>V
* @return Returns the page. 1w?DSHe
*/ i ;YRE&X
public Page getPage(){ t9kqX(!
return page; <C7/b#4>\
} m3b?f B
1b"3]?
/** }l@7t&T|
* @param content Q"{Q]IT
* The content to set. V_Y2 @4
*/ MW.,}f
public void setContent(List content){ !L'O")!3
this.content = content; v/C*?/ ~
} ^$\#aTyFK
{[FJkP2l
/** 8F`799[p
* @param page }KL( -Ui$
* The page to set. jowR!rqf
*/ &
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publicvoid setPage(Page page){ P0szY"}
this.page = page; "CWqPcr
} T`^LWc"
} y
+c 3#
Os|F
NIOWjhi[Jn
4}=Z+tDu>
X=b]Whuv
2. 编写业务逻辑接口,并实现它(UserManager, rexy*Xv`2p
GI*2*m!u
UserManagerImpl) gNo}\
lm4V
java代码: V_7QWIdiy>
vJ!<7 l&
*Ry
"`"
/*Created on 2005-7-15*/ 5},kXXN{+
package com.adt.service; $P~Tt 4068
3MFb\s&Fq
import net.sf.hibernate.HibernateException; SQVyCxcX_
'x\{sv
import org.flyware.util.page.Page; -qndBS
w4p<q68
import com.adt.bo.Result; E?P:!V=_
AVv 8Hhd
/** 0Fm,F&12
* @author Joa 3P2L phW
*/ ;F'/[l{+
publicinterface UserManager { 5U&?P
&8wluOs/5
public Result listUser(Page page)throws 3sq(FsT
^c]lEo
HibernateException; :>otlI<0t
q'awV5y
} E#cZM>
.9;wJ9Bw[
5%Q[X
rN^P//
7Cj6Kw5k
java代码: QZ51}i
qy|si4IU8,
VjVL/SO/
/*Created on 2005-7-15*/ %7bZnK`C
package com.adt.service.impl; LK[%}2me
X>y6-%@
import java.util.List; b}#ay2AR
u0& dDZ
import net.sf.hibernate.HibernateException; oVSq#I4
;iEFG^'tG
import org.flyware.util.page.Page; KUqD<Jj?
import org.flyware.util.page.PageUtil; ${%*O}$
~'l.g^p bv
import com.adt.bo.Result; *b0f)y3RV
import com.adt.dao.UserDAO; P*;zDQy
import com.adt.exception.ObjectNotFoundException; Xz, sL
import com.adt.service.UserManager; +b]+5!
h
.$3jNU
/** C6C7*ks
* @author Joa Z,osdF
*/ |YAnd=$
publicclass UserManagerImpl implements UserManager { C7[CfcPA
=-qv[;%&6
private UserDAO userDAO; pP6pn~}
W=T}hA#`
/** _:tisr{
* @param userDAO The userDAO to set. \;G 97o
*/ qrmJJSJ
publicvoid setUserDAO(UserDAO userDAO){ b 64~Y|8
this.userDAO = userDAO; l1qWl
} `cgSyRD]
t~0}Emgp<(
/* (non-Javadoc) `<L6Q2Y>j
* @see com.adt.service.UserManager#listUser {
+%S{=j
~^Y(f'{
(org.flyware.util.page.Page) U\ A*${
*/ -IB~lw
public Result listUser(Page page)throws $fE$j {
A,T3%TE
HibernateException, ObjectNotFoundException { M/,jHG8v
int totalRecords = userDAO.getUserCount(); &<P!o_+eb
if(totalRecords == 0) v&EHp{8Qd
throw new ObjectNotFoundException 3Yd)Fm
H+>l][
("userNotExist"); ZdD]l*.\i
page = PageUtil.createPage(page, totalRecords); Rz!E=1Y$
List users = userDAO.getUserByPage(page); f}'E|:Z 7k
returnnew Result(page, users); n2+eC9I
} \5%T'S@5
0r+%5}|-K
} uz1t uX_
c!BiGw,;
W1s4[rL!Ht
m"!!)
v?\bvg\E
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5"[Qs|VjA6
%@{);5[
询,接下来编写UserDAO的代码: DaW_-:@s
3. UserDAO 和 UserDAOImpl: 24Y~x`W
java代码: Z;_WU
oh5fNx
\DE`tkV8
/*Created on 2005-7-15*/ j_?U6$xi
package com.adt.dao; uL!{xuN
hNV"{V3`{
import java.util.List; g=;c*{
,OLN%2Sq
import org.flyware.util.page.Page; S)[`Bm
H!ZPP8]j>
import net.sf.hibernate.HibernateException; or u.a
ESZ6<!S
/** b
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A
* @author Joa g|PVOY+|^
*/ ~mtL\!vaM
publicinterface UserDAO extends BaseDAO { Mp~E$f
R4"g?
e
publicList getUserByName(String name)throws 1e;^MzB"
l|fOi A*K
HibernateException; /._wXH
~<pGiW'w5
publicint getUserCount()throws HibernateException; 1X/
q7lR
e/WR\B'1
publicList getUserByPage(Page page)throws J*8fGR%
C,w$)x5kls
HibernateException; ztG_::QtG]
DB yRP-TH
} +>oVc\$
aT#R#7<Eg
5w`v
3o
!V.'~xj
S)GWr"m-
java代码: i+&*W{Re
"6n~,$
n-dO |3,
/*Created on 2005-7-15*/ Z8Fbx+~"
package com.adt.dao.impl; S5'BXE,
#`/KF_a3\>
import java.util.List; 5isejR{r
7 [55
import org.flyware.util.page.Page; Z-b^{uP
K ^1bR(a
import net.sf.hibernate.HibernateException; _EOQ*K#=Ct
import net.sf.hibernate.Query; EpeTfD
"j9,3yJT
import com.adt.dao.UserDAO; JLRw`V,o7
NrTQ}_3)
/** "7RQrz
* @author Joa '?_;s9)
*/ gQ*0Mk
public class UserDAOImpl extends BaseDAOHibernateImpl r9G<HKl
@3{'!#/
implements UserDAO { \{n]&IjA
i
4eb\j
/* (non-Javadoc) B5!$5Qc
* @see com.adt.dao.UserDAO#getUserByName 0?ZJJdI3
<?,o
{
(java.lang.String) *;O$=PE
*/ ;*+jCL2F
publicList getUserByName(String name)throws /+Xv(B
|J2Rwf
HibernateException { (hVhzw"~
String querySentence = "FROM user in class u|=_!$8
`Y/DttjL
com.adt.po.User WHERE user.name=:name"; )oa6;=go
Query query = getSession().createQuery &&|*GAjJ
ow
~(k5k:
(querySentence); 0W9,uC2:N
query.setParameter("name", name); ;|b
D@%@
return query.list(); xF5q=%n
} R1X9
`Bnp/9q5
/* (non-Javadoc) \A _g
* @see com.adt.dao.UserDAO#getUserCount() )=;0
*/ on+
c*#
publicint getUserCount()throws HibernateException { z:|4S@9
int count = 0; 9rtcI[&?0
String querySentence = "SELECT count(*) FROM /_?Ly$>'
6Ez}A|i
user in class com.adt.po.User"; ge[f/"u
Query query = getSession().createQuery Q,Hw@w<1
{Os$Uui37\
(querySentence); h{yqNl
count = ((Integer)query.iterate().next s6w</
Z6X?M&-Lz
()).intValue(); veAGUE
%3
return count; 5Y"lr Y38
} *\I?gDON
myFjw@
/* (non-Javadoc) Z=
dEk`
* @see com.adt.dao.UserDAO#getUserByPage Txfu%'2)e
ZyT9y
(org.flyware.util.page.Page) m
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*/ "kz``6C
publicList getUserByPage(Page page)throws E:(flW=
^:\|6`{n
HibernateException { 0eQyzn*98
String querySentence = "FROM user in class rcPP-+XW
W{At3Bfy
com.adt.po.User"; [(w_!|S
Query query = getSession().createQuery 1Qtojph
&n6mXFF#>P
(querySentence); V(A6>0s$|
query.setFirstResult(page.getBeginIndex())
7<oLe3fbM
.setMaxResults(page.getEveryPage()); E:f0NV3"1
return query.list(); t*<.^+Vd
} *n N;!*J
uv}[MXOP
} ,+KZn}>
s$:F^sxb
pRD8/7@(B{
"CB*
\('8_tqI"
至此,一个完整的分页程序完成。前台的只需要调用 ( N~[sf?&
+y>D3I
userManager.listUser(page)即可得到一个Page对象和结果集对象 eRD?O
A/,7%bB1
的综合体,而传入的参数page对象则可以由前台传入,如果用 wZ,9~P7
^vLHs=<
webwork,甚至可以直接在配置文件中指定。 q[nX<tO
]ZelB,7q
下面给出一个webwork调用示例: _0 USe
java代码: (01M 0b#
~C{d2i
bPAp0}{Fu
/*Created on 2005-6-17*/ :O{`!&[>L
package com.adt.action.user; *{P"u(K
,o]"G[Jk
import java.util.List; k+{-iPm{
>o>r@;
import org.apache.commons.logging.Log; 4WG~7eIgy
import org.apache.commons.logging.LogFactory; !uii|"
import org.flyware.util.page.Page; @3K)VjY7
YW}q@AY7
import com.adt.bo.Result; (!&cfabL
import com.adt.service.UserService; _y#t[|}w
import com.opensymphony.xwork.Action; p-GlGEt_X
=da_zy
/** >;dMumX
* @author Joa 3 ~0Z.!O
*/ a=&a)FR
publicclass ListUser implementsAction{ GN /]^{D
p)N=
privatestaticfinal Log logger = LogFactory.getLog FRQ0tIp
G,e>dp_cPu
(ListUser.class); EkgS*q_
<- Q=h?D
private UserService userService; FylL7n
(YF`#v6
private Page page; 'xm _oGWE
fmXA;^%
privateList users; &/d;4Eu
1D&Q{?RM
/* ]vMr@JM-G
* (non-Javadoc) M%7{g"J*
* 9Ruj_U
* @see com.opensymphony.xwork.Action#execute() ;"hED:z6%
*/ ZMy0iQ@
publicString execute()throwsException{ d_BECx<\
Result result = userService.listUser(page); YgNt>4K
page = result.getPage(); ^]3Y11sI
users = result.getContent(); sWP5=t(i+9
return SUCCESS; Yj|Oy
} ,`v)nwP
tI|?k(D
/** K4YpE}]u
* @return Returns the page. 'due'|#^
*/ UM(tM9
public Page getPage(){ r j#K5/df
return page; %| }obiV)
} ,di'279|
dElOy?v
/** Q0i.gEwe
* @return Returns the users. iY1%"x
*/ @cA`del
publicList getUsers(){ d!5C$C/x
return users; x+x6F
} +!6aB|-
"rOe J~4 X
/** ml <X92Y
* @param page ,4zwd@&O
* The page to set. >!MOgLO3
*/ K9B_o,
publicvoid setPage(Page page){ ?2zVWZ
this.page = page; \ce (/I
} `[p*qsp_
Fq>=0 )
/** ;,![Lar5L
* @param users "Lk-R5iFd
* The users to set. @.;] $N&J
*/ ,)e&u1'
publicvoid setUsers(List users){ &Ed7|k]H
this.users = users; _fx0-S*$
} zZ&L#
D1o<:jOj
/** k
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* @param userService o^hI\9
* The userService to set. REUWK#>
*/ wYQTG*&h
publicvoid setUserService(UserService userService){ mr
dG-t(k
this.userService = userService; +b"RZ:tKp
} bwR_ uF
} ZqT?7 |i
+ntrp='7O7
P9=L?t.
PXqLK3AE
3^AycwNBA
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, eL3HX _2(
GO{o #}
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 "| 0g 1rd
47>IT
么只需要: 64;F g/t
java代码: L1A0->t
?muI8b
MG)wVS<d_
<?xml version="1.0"?> M>W-lp^3
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ,3l=44*
Kk#g(YgNz
1.0//EN" "http://www.opensymphony.com/xwork/xwork- fmyyQ|]O"
]L#6'|W
1.0.dtd"> 7?a@i;E<
T\ZWKx*#
<xwork> D%GB2-j R
_9!*laR!2
<package name="user" extends="webwork- mL/]an@Y
=<mpZ'9gW
interceptors"> gdkl,z3N3
q$FwO"dC
<!-- The default interceptor stack name
SbQ Ri
jiQJ{yY
--> 0f~7n*XH
<default-interceptor-ref u=NpL^6s<
2<HG=iSf
name="myDefaultWebStack"/> Z0*Lm+d9z
y57]q#k
<action name="listUser" H }w"4s
EV{kd.=f
class="com.adt.action.user.ListUser"> '{=dEEi
<param 5N
"fD{v{
XOgl>1O
name="page.everyPage">10</param> V^fSrW]
<result 7KIOI,qb6
L".Qf|b*
name="success">/user/user_list.jsp</result> td!WgL,m
</action> V
;Kzh$^rk
?mKj+Bk2
</package> *#+e_)d
3]xe7F'`
</xwork> <Wc98m
k$
k/U
4/YEkD
/ *3[9,
G{$(t\>8
:K&>
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 @8WG
i(DoAfYf/q
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 <cu? g
Q79& Q04XN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 \Y.&G,?
%qA@)u53
C"l_78
"q@OMf
<[{Ty+
我写的一个用于分页的类,用了泛型了,hoho BG:l Zj'I
6&/H
XqP
java代码: p;Ezmz
v~^c-]4I
?^]29p_
package com.intokr.util; &atT7m
PZ5BtDm
import java.util.List; 7tWt3
8BZTHlUB
/** 9F+i+(\,b
* 用于分页的类<br> P|}~=2J
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 2>~{.4PI
* =
7U^pT
* @version 0.01 w?_y;&sbR
* @author cheng tY$
.(2Ua
*/ +C3IP
public class Paginator<E> { !wH7;tU
privateint count = 0; // 总记录数 @k+Z?Hp
privateint p = 1; // 页编号 4T#B7wVoM
privateint num = 20; // 每页的记录数 g-^Cf
privateList<E> results = null; // 结果 3&Dln
(I3:u-A
/** V9xZH5T8^
* 结果总数 *o]Q<S>lH
*/ _nw=^zS
publicint getCount(){ {SH+lX0]{
return count; ZUGuV@&-T
} _Eq*
=hE5 ?}EP+
publicvoid setCount(int count){ (ov=D7>t0
this.count = count; NJJsg^'
} :%GxU;<E{
oXw} K((|
/** d"zbY\`
* 本结果所在的页码,从1开始 uv*OiB"
* "0Xa?z8"
* @return Returns the pageNo. Bi?.w5
*/ cU}j
Whu
publicint getP(){ l!Q |]-.@
return p; [s?H3yQ.
} A#9@OWV5f
C6Qnn@waYb
/** \ZdV|23
* if(p<=0) p=1 LF+#PnK
* n99>oh
* @param p bni :B?#
*/ )@DT^#zR
publicvoid setP(int p){ aYQ!`mS::M
if(p <= 0) v5"5UPi-
p = 1; AHsp:0Ma#
this.p = p; [
bv>(a_,
} ?>47!):-*
W]|;ZzZ=m
/** 77/&M^0
* 每页记录数量 ) *:<3g!
*/ a&YD4DQ05
publicint getNum(){ }>:v
return num; 2^ 'X
} zRyZrt,%&
FG8genCH@
/** 4xLU15C
* if(num<1) num=1 3\eb:-B:@
*/ iN%\wkx*N
publicvoid setNum(int num){ x#yL&+'?Mj
if(num < 1) ]9z{
95
num = 1; S9X~<!]
this.num = num; f:L%th
} uiq)?XUKv
,6rg00wGE
/** kM>0>fkjE
* 获得总页数 I^ W
*/ @DK,ka(
publicint getPageNum(){ [.tqgU
return(count - 1) / num + 1; b{H&%Jx)
} 6L@g]f|Y@
=!3G ,qV
/** GCul6,w
* 获得本页的开始编号,为 (p-1)*num+1 Q7]:vs)%
*/ |YjuaXd7N
publicint getStart(){ RW
23lRA6
return(p - 1) * num + 1; $x;wnXXXM
} cad1eOT'
8EZ"z
d`n/
/** >*%ySlZbs
* @return Returns the results. JBQ,rX_Hw
*/ R{S{N2+p(
publicList<E> getResults(){ M@@"-dy
return results; bG
nBV7b
} =g'7 xA
c0ET]
public void setResults(List<E> results){ *ie#9jA
this.results = results; m;o \.s
} *=}$@OS
Gad!}dz
public String toString(){ +GMM&6<
StringBuilder buff = new StringBuilder K9
'/
3..3k
(); NwM =
buff.append("{"); -WP_0
buff.append("count:").append(count); |;{^Mci%
buff.append(",p:").append(p); 2vWJ|&|p
buff.append(",nump:").append(num); >69xl^Gd
buff.append(",results:").append R7cY$K{j
5o\yhYS:
(results); '7[{ISBXU
buff.append("}"); pc}Q_~e
return buff.toString(); M=n!tVlCV
} YhFB*D;
Dw
} M5 ep\^
{/12.y=)~
<jU[&~p