Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .&2Nm&y$K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 |';oIYs|$
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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 (`me}8
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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 sm9/sX!
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分页支持类: '%y5Dh
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java代码: FBGe s[,
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package com.javaeye.common.util; R?L?6~/q
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import java.util.List; uZhY)o*]@
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publicclass PaginationSupport { WkUV)/j
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publicfinalstaticint PAGESIZE = 30; wJMk%N~R:
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privateint pageSize = PAGESIZE; .mwB'Ll
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privateList items; &$L6*+`h#
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privateint totalCount; Zc|V7+Yx
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privateint[] indexes = newint[0]; 4157!w'\y
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privateint startIndex = 0; 6i`Y]\X~#
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public PaginationSupport(List items, int 7I4<Dj
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totalCount){ \h48]ZjC`
setPageSize(PAGESIZE); EV.F/Wh
setTotalCount(totalCount); zz**HwRt
setItems(items); Sk7sxy<F'
setStartIndex(0); /C\tJs
} 2m{d>
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public PaginationSupport(List items, int %yPjPUHy
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totalCount, int startIndex){ G<:gNWXd\
setPageSize(PAGESIZE); `)WC|= w2
setTotalCount(totalCount); M7gb3gw6
setItems(items); g)L<xN8
setStartIndex(startIndex); [M/0 Qx[,
} f(UB$^4
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public PaginationSupport(List items, int Ls6C*<8
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totalCount, int pageSize, int startIndex){ ,Z$!:U
setPageSize(pageSize); U~I
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setTotalCount(totalCount); Rv)*Wo!L
setItems(items); [!ilcHE)
setStartIndex(startIndex); +%!'~
} ?"-1QG
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publicList getItems(){ C/#?S=w`4
return items; ;6}> Shs
} 0T2^$^g
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publicvoid setItems(List items){ w:nLm,
this.items = items; {!>'#
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} :`B70D8ku
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publicint getPageSize(){ t>}(`0
return pageSize; VOGx
} vww>] Z}
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publicvoid setPageSize(int pageSize){ -Dy":/Bk
this.pageSize = pageSize; WJTc/
} BT^HlW<
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publicint getTotalCount(){ 6Wk9"?+1
return totalCount; !S#K6:
} k@P?,r
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publicvoid setTotalCount(int totalCount){ * -X`^R
if(totalCount > 0){ LbUH`0:%t
this.totalCount = totalCount; p`)Mk<`dYD
int count = totalCount / C8KV<k
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pageSize; '37 <+N
if(totalCount % pageSize > 0) 'OI(MuSn
count++; UK5u"@T
indexes = newint[count]; k2/t~|5
for(int i = 0; i < count; i++){ h{ T{3
indexes = pageSize * Vl/fkd,Z
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i; te;VGpv.
} :_[pZ;-@
}else{ B|ctauJ
this.totalCount = 0; UetI4`
} 3$4I
} {[~dI ~
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publicint[] getIndexes(){ sL)7MtNwy
return indexes; "EBCf.3-
} Q9k;PJ`@
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publicvoid setIndexes(int[] indexes){ nQ@<[KNd
this.indexes = indexes; 4}-G<7*
} m:Fdgu9
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publicint getStartIndex(){ :Z.P0=
return startIndex; zNM*xPgS
} 2"EaF^?\
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publicvoid setStartIndex(int startIndex){ !@>q^_Gez
if(totalCount <= 0) nCDG PzJ
this.startIndex = 0; D<'G\#n3I=
elseif(startIndex >= totalCount) J\hqK*/8
this.startIndex = indexes Ze?n Q-
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[indexes.length - 1]; 'HJ<"<
elseif(startIndex < 0) ]JQ}9"p=5
this.startIndex = 0; M44$E4a20
else{ Ym?VF{e,
this.startIndex = indexes
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}b^x#HC
[startIndex / pageSize]; umN4|X
} xoQ(GrBY
} -`D<OSt7
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publicint getNextIndex(){ "dHo6CT,y_
int nextIndex = getStartIndex() + )cU$I)
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pageSize; 5[]Yx l
if(nextIndex >= totalCount) qwq5yt?
return getStartIndex(); Fg0!2MKq*
else d^8n
return nextIndex; LtGjHB\+
} O-!Q~;3][
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publicint getPreviousIndex(){ S@Aw1i p
int previousIndex = getStartIndex() - Z|xgZG{
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pageSize; ]IH1_?HgP7
if(previousIndex < 0) <vt}+uMzXv
return0; 8x-(7[#e<g
else j!"5,~
return previousIndex; ~9#'s'
} 5p ,HkV
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} [WI'oy
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抽象业务类 /4;Sxx-
java代码: G +AP."M?
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/** UkcH+0o
* Created on 2005-7-12 `A<2wd;
*/ K{:[0oIHc
package com.javaeye.common.business; LTuT"}dT[
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import java.io.Serializable; r}}2Kl
import java.util.List; vy-q<6T}:p
sl:1P^b
import org.hibernate.Criteria; K^P&3H*(/n
import org.hibernate.HibernateException; VAA="yN
import org.hibernate.Session; <fHN^O0TS
import org.hibernate.criterion.DetachedCriteria; LtPaTe
import org.hibernate.criterion.Projections; ^fE8|/]nG9
import |Xt6`~iC
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org.springframework.orm.hibernate3.HibernateCallback; :KqSMuKR
import Jp=
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/
org.springframework.orm.hibernate3.support.HibernateDaoS Ii<k<Bt,
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upport; q2s=>J';
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import com.javaeye.common.util.PaginationSupport; ^$]iUb{\
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public abstract class AbstractManager extends K+~1z>&
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HibernateDaoSupport { ~[=d{M!$W
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privateboolean cacheQueries = false; n2|@Hz_
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privateString queryCacheRegion; =Y*@8=V
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publicvoid setCacheQueries(boolean <[$a7l i
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cacheQueries){ Dl,sl>{
this.cacheQueries = cacheQueries; Sjo-Xf}
} w`v`aw]
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publicvoid setQueryCacheRegion(String "&o"6ra}
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queryCacheRegion){ y`z4S,
this.queryCacheRegion = C~pQJ@bF0
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queryCacheRegion; ^=8/I w
} wd3OuDrU
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publicvoid save(finalObject entity){ *j=58d`n
getHibernateTemplate().save(entity); Ti7
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} PPh<9$1\g
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publicvoid persist(finalObject entity){ |oSqy
getHibernateTemplate().save(entity); g yegdky3
} Y!+H9R
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publicvoid update(finalObject entity){ hj{)6dBX%
getHibernateTemplate().update(entity); bYqv)_8
} ?zfm"o
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publicvoid delete(finalObject entity){ gk;hpO
getHibernateTemplate().delete(entity); QO>';ul5
} 7]ySj<1
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publicObject load(finalClass entity, hQ@#h`lS
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finalSerializable id){ Fnay{F8z
return getHibernateTemplate().load w`fbUh6/
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(entity, id); ].2t7{64
} :4\%a4{Ie
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publicObject get(finalClass entity, CD5% iFy
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finalSerializable id){ ;-BN~1Jg
return getHibernateTemplate().get \En"=)A
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(entity, id); [rW];H8:~
} T8%!l40v
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publicList findAll(finalClass entity){ An^)K
return getHibernateTemplate().find("from W*Ow%$%2
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" + entity.getName()); 6J@,bB
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} C%{2 sMJz
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publicList findByNamedQuery(finalString 'X6Z:dZY
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namedQuery){ !aKu9SR^e
return getHibernateTemplate 2-jXj9kp`
f~ /hsp~Hp
().findByNamedQuery(namedQuery); 7WY~v2SDF
} 1Kr$JIcd
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publicList findByNamedQuery(finalString query, DuT6Od/f
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finalObject parameter){ gsUF\4A(J
return getHibernateTemplate !YI<A\P
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().findByNamedQuery(query, parameter); Zu~w:uNmU
} u&[L!w
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publicList findByNamedQuery(finalString query, bfm+!9=9S
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finalObject[] parameters){ {qU;;`P]|
return getHibernateTemplate X6_
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!3\$XK]5ZT
().findByNamedQuery(query, parameters); M d8(P23hS
} sC.r$K+k5
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publicList find(finalString query){ 4:^MSgra
return getHibernateTemplate().find pLCS\AUTsv
uB3VCO.;_
(query); $ZZ?*I
} )?7/fF)@|
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publicList find(finalString query, finalObject VH<d[Mj
WPAUY<6f
parameter){ !M`.(sO]
return getHibernateTemplate().find
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mEu2@3^E }
(query, parameter); ]$ Nhy8-
} i*$~uuY
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public PaginationSupport findPageByCriteria `(`-S
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(final DetachedCriteria detachedCriteria){ cruBJZr*
return findPageByCriteria = :zPT;K
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); XjP&
} /#SfgcDt
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public PaginationSupport findPageByCriteria ]7>#YKH.
l6 }+,v@#
(final DetachedCriteria detachedCriteria, finalint f~PS'I_r
3$q#^UvD
startIndex){ GDe,n
return findPageByCriteria 4b((,u$
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(detachedCriteria, PaginationSupport.PAGESIZE, WT")tjVKA
/$]S'[5uF
startIndex); 4o;;'P
} <DPRQhNW]
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public PaginationSupport findPageByCriteria 6<>1,wbq
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(final DetachedCriteria detachedCriteria, finalint r_T"b
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pageSize, nTGZ2C)c<'
finalint startIndex){ HRrR"b9:
return(PaginationSupport) FG+pR8aA$
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getHibernateTemplate().execute(new HibernateCallback(){ =$^90Q,Z;
publicObject doInHibernate TBQ68o
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(Session session)throws HibernateException { &JKQH
Criteria criteria = doe3V-if
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detachedCriteria.getExecutableCriteria(session); 0Z]HH+Z;
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount O(2c_! d
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()).uniqueResult()).intValue(); o<txm ?+N
criteria.setProjection ,H,[)8
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(null); "crp/Bj?
List items = OFmHj]I7=
r|*_KQq
criteria.setFirstResult(startIndex).setMaxResults 9`
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(pageSize).list(); [7~AWZU3
PaginationSupport ps = n1JV)4Mv
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new PaginationSupport(items, totalCount, pageSize, MBw;+'93qf
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startIndex); G4~@
return ps; VF";p^
} >i >|]
}, true); 8#tuB8>
} oF]]Pl{W
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public List findAllByCriteria(final )g^qgxnnV
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DetachedCriteria detachedCriteria){ mDZA\P_
return(List) getHibernateTemplate oIx|)[
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().execute(new HibernateCallback(){ 94dd )/a
publicObject doInHibernate ,%N[FZ`|
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(Session session)throws HibernateException { febn?|@
Criteria criteria = u/S>*E
SiaW; ks
detachedCriteria.getExecutableCriteria(session); /5"T46jD
return criteria.list(); $ (xdF
} 1 n&%L8]
}, true); Sw"h!\c`
} P(2OTfGGx
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public int getCountByCriteria(final RPf <-J:t
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DetachedCriteria detachedCriteria){ Qc?W;Q+
Integer count = (Integer) p%sizn
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getHibernateTemplate().execute(new HibernateCallback(){ z,E`+a;
publicObject doInHibernate 3 )#Nc|
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(Session session)throws HibernateException { Ee7+ob
Criteria criteria = L[D+=
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detachedCriteria.getExecutableCriteria(session); k+?gWZ\
return Jq(;BJ90R
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criteria.setProjection(Projections.rowCount Z'2AsT
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()).uniqueResult(); {D..(f1*u
} 3(t,x
}, true); z#PaQp5F
return count.intValue(); jVN06,3z
} #-f9>S9_
} ZYY2pY 1
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用户在web层构造查询条件detachedCriteria,和可选的 ,"gPd!HD(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [?9 `x-Q
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PaginationSupport的实例ps。 :2==7u7v?
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ps.getItems()得到已分页好的结果集 B|"i`{>
ps.getIndexes()得到分页索引的数组 i.Y2]1
ps.getTotalCount()得到总结果数 hF@%k
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ps.getStartIndex()当前分页索引 zng.(]U/?H
ps.getNextIndex()下一页索引 =fnBE`Uc
ps.getPreviousIndex()上一页索引 n
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 *'A*!=5(
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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 1 /{~t[*.
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一下代码重构了。 _Y&.Nw
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我把原本我的做法也提供出来供大家讨论吧: ]jVE
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首先,为了实现分页查询,我封装了一个Page类: |X A0F\
java代码: fvH{va.
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/*Created on 2005-4-14*/ m{RXt
package org.flyware.util.page; %}zkmEY.e
4D<C;>*/b
/** O<L=N-
* @author Joa U*Y]cohh
* 2/V%jS[4#y
*/ |T/OOIA=sI
publicclass Page { Zv9JkY=+@
9XDSL[[
/** imply if the page has previous page */ x X3I`
privateboolean hasPrePage; Q[NoFZ
V!
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/** imply if the page has next page */ bK0(c1*a[e
privateboolean hasNextPage; jR[c3EA
;
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/** the number of every page */ 8+gp"!E
privateint everyPage; j?|Vx'
[s]$&
/** the total page number */ :fL7"\
pf~
privateint totalPage; K.wRz/M&g
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/** the number of current page */ 57;0,k5Gy
privateint currentPage; H^S<bZ
<^5$))r
/** the begin index of the records by the current `Rt w'Uz
-['& aey}a
query */ B1~`*~@
privateint beginIndex; 5&EBUl}
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/** The default constructor */ zT&"rcT">
public Page(){ -A<@Pg
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} K O\HH
<v'[Wl@hq
/** construct the page by everyPage z)^.ai,: 0
* @param everyPage OwNM`xSa|\
* */ BI,]pf;GWv
public Page(int everyPage){ 2Ul8<${c{
this.everyPage = everyPage; EHf,VIC8
} V~/@KU8cH
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/** The whole constructor */ 0Mn|Yb4p
public Page(boolean hasPrePage, boolean hasNextPage, r7_%t_O|IL
$X Uck[
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int everyPage, int totalPage, ?b(wZ-/
int currentPage, int beginIndex){ PbvA~gm
this.hasPrePage = hasPrePage; "y7\F9
this.hasNextPage = hasNextPage; %`5K8eB
this.everyPage = everyPage; R|)l^~x
this.totalPage = totalPage; ZoJqJWsd
this.currentPage = currentPage; %$ o[,13=
this.beginIndex = beginIndex; ~ PyS;L}
} <aaT,J8%[
9fbbJ"I+
/** P(@Q[XQ2
* @return N&
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* Returns the beginIndex. \ Qx%76
*/ LD?\gK"
publicint getBeginIndex(){ #Pd__NV"\
return beginIndex; *74/I>i
} 19O
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/** F`eE*&
* @param beginIndex i; ]0>g4
* The beginIndex to set.
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*/ .3_u5N|[=W
publicvoid setBeginIndex(int beginIndex){ ]CcRI|g}
this.beginIndex = beginIndex; _\k?uUo&,^
} ;!
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/** J"E _i]
* @return ^.@%n1I"5y
* Returns the currentPage. MRo_An+
*/ j`@`M*)GB
publicint getCurrentPage(){ q!U$\Q&
return currentPage; K>~YO~~
} \5<Z [#{
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/** a"O;DYh
* @param currentPage p]y.N)a
* The currentPage to set. {0,6-dd5
*/ sx7zRw
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publicvoid setCurrentPage(int currentPage){ oBub]<.J
this.currentPage = currentPage; {)b
} #d[Nm+~ko
& uwOyb
/** VR"le&'z"
* @return 5Zhl@v,L%
* Returns the everyPage. KCZ<#ca^
*/ zXlerQWUv
publicint getEveryPage(){ jbZTlG
return everyPage; I~~":~&
} )
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/** / s Apj
* @param everyPage \@h$|nb
* The everyPage to set. nLk`W"irM
*/ [h
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publicvoid setEveryPage(int everyPage){ ]i,o+xBKH
this.everyPage = everyPage; -Mrt%1g
} $Q'LDmot
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/** v
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* @return 3
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* Returns the hasNextPage. RRQv<x
*/ ->IZZ5G<
publicboolean getHasNextPage(){ i-wWbZ-
return hasNextPage; x_-V{
k
} T)q
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H
mb3aUFxA;
/** 2PeMt^
* @param hasNextPage !^NZp%Yd
* The hasNextPage to set. Hiwij,1
*/ =)jo}MB
publicvoid setHasNextPage(boolean hasNextPage){ }|8^+V&
this.hasNextPage = hasNextPage; 6~{'\Z
} "G*$#
S"^'ksL\
/** jd5kkX8=
* @return
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* Returns the hasPrePage. 9qGba=}Ey
*/ :,$"Gk
publicboolean getHasPrePage(){ E^{!B]/oP
return hasPrePage; *+6iXMwe
} (5:pHX`P
/7+b.h])^
/** L|s\IM1g
* @param hasPrePage e87a9ZPm
* The hasPrePage to set. $7Z-Nn38
*/ 6#jql
publicvoid setHasPrePage(boolean hasPrePage){ %B1TN#KoT
this.hasPrePage = hasPrePage; mv,a>Cvs[
} T <k;^iqR
D-i, C~W
/** 6'uCwAQU
* @return Returns the totalPage. X$Q.A^9
* Vep41\g^
*/ 726UO#*
publicint getTotalPage(){ 3PLA*n+%
return totalPage; ,|zzq@fk
} Tz9 (</y
pJl/d;Cyrb
/** Q3bU"f
* @param totalPage ;;CNr_
* The totalPage to set. (OwGp3g
*/ w<]-~`K
publicvoid setTotalPage(int totalPage){ 1!U:M8T|
this.totalPage = totalPage; jyyig%
} b9T6JS j
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} )~"0d;6_
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*$;Zk!sEF
a
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 {(Mmv[y
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个PageUtil,负责对Page对象进行构造: z_KCG2=5
java代码: -h
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/*Created on 2005-4-14*/ ]8$H 'u(C
package org.flyware.util.page; &AeNrtGu
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import org.apache.commons.logging.Log; 4!96k~d}
import org.apache.commons.logging.LogFactory; [,ulz4"
;+o6"ky5
/** / <+`4n
* @author Joa cAVdH{$"
* lMg#zT!?
*/ $txF|Fj]^A
publicclass PageUtil { )~nieQEZQ
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privatestaticfinal Log logger = LogFactory.getLog EDnZ/)6Gg
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(PageUtil.class); rL+.3ZO):P
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/** IBu\Sh-
* Use the origin page to create a new page (LXYx<
* @param page fshG ~L7S9
* @param totalRecords HKO]_; :(
* @return v7#|%
*/ ,BGUIu6
publicstatic Page createPage(Page page, int V=1zk-XC
|:2B )X
totalRecords){ 5~2_wWjX
return createPage(page.getEveryPage(), c1y+kvv
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page.getCurrentPage(), totalRecords); BE~-0g$W
} _]D
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/** 0sme0"Sl
* the basic page utils not including exception 9pS:#hg
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handler R@_3?Z!W=
* @param everyPage sD{Wc%5
* @param currentPage kG}F/GN?
* @param totalRecords `2x. -
* @return page ^rjUye%EK
*/ 7ju38@+
publicstatic Page createPage(int everyPage, int jk\V2x@DR
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currentPage, int totalRecords){ WT1y7+_g(d
everyPage = getEveryPage(everyPage); T
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currentPage = getCurrentPage(currentPage); gLZJQubz
6
int beginIndex = getBeginIndex(everyPage, N cGFPi(Z
M:& %c3
currentPage); l2dj GZk
int totalPage = getTotalPage(everyPage, cF9oo%3
C6@*l~j
totalRecords); ^mC,Z+!
boolean hasNextPage = hasNextPage(currentPage, tc\ZYCFr
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totalPage); n^5Q
f\ o
boolean hasPrePage = hasPrePage(currentPage); -F3~X R
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returnnew Page(hasPrePage, hasNextPage, 5e0d;Rd
everyPage, totalPage, ),j6tq[
currentPage, bF+j%=
]A#:Uc5
beginIndex); MOp "kA
} W_3BL]^=
M_r[wYt!
privatestaticint getEveryPage(int everyPage){ )<_qTd0`
return everyPage == 0 ? 10 : everyPage; 2*Pk1vrI
} !u
.n
#
kNp);
privatestaticint getCurrentPage(int currentPage){ O2="'w'kR
return currentPage == 0 ? 1 : currentPage; ~ kDJ-V
} D+~*nc ~
g
e5 zi "~
privatestaticint getBeginIndex(int everyPage, int ) vVf- zU
WQD:~*C:
currentPage){ 1cRF0MI
return(currentPage - 1) * everyPage; HNj;_S
} fM*?i"j;Y
G8/q&6f_
privatestaticint getTotalPage(int everyPage, int ,\#s_N7
cN&:V2,
totalRecords){ C|3cQ{
int totalPage = 0; ZBN,%P!P0
72*j6#zS
if(totalRecords % everyPage == 0) KMQPA>w#
totalPage = totalRecords / everyPage; e L}X().
else `P*BW,P'T
totalPage = totalRecords / everyPage + 1 ; |90X_6(
du#f_|xG
return totalPage; tXZMr
} 8IBr#+0
9nFWJn
privatestaticboolean hasPrePage(int currentPage){ $\~cWpv
return currentPage == 1 ? false : true; PDCb(5
} Ze#DFe$
gNA!)}m\
privatestaticboolean hasNextPage(int currentPage, unbIfl=
p0]\QM l1
int totalPage){ :)tsz;
return currentPage == totalPage || totalPage == V
d]7v
|GsMLY:0
0 ? false : true; M_2>b:#A*
} "Ehh9 m1&
KtH^k&z.f
l+hOD{F4pS
} Em5,Zr_
u%I%4 gM
#e,TS`"eD
kp}[nehF
s@y;b0$gk
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 oGl<i
6iF&!Fd>J
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 (uhE'IQ{(
X7`-dSVE
做法如下: vH1,As
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ^Qn:#O9
Y%- !%|
的信息,和一个结果集List: @EyB^T/
java代码: `NEi/jB
IA[:-2_
c=9A d
/*Created on 2005-6-13*/
&1&OXm$
package com.adt.bo; M V!d*\
;FF+uK
import java.util.List; y;<suGl
BGwD{6`U
import org.flyware.util.page.Page; l"DHG`kb
,R3TFVV!?
/** m.! M#x2!
* @author Joa t,*1=S5
*/ 5;XYF0
publicclass Result { ED" fi$
XuHR
private Page page; Wi>m}^}9
%N`_g' r!
private List content; 6akI5\b
$?]`2*i
/** SBs! 52
* The default constructor 4#]g852
*/ M6^
\LtFt
public Result(){ cL;%2TMk
super(); \@N~{72:k
} ]j6K3
)cZHBG.0H
/** .>.GQUr
* The constructor using fields #=33TvprR2
* O"\_%=X9
* @param page bGK*1FlH
* @param content EJb+yy6
*/ |O oczYf
public Result(Page page, List content){ Yg,b
;H
this.page = page; j u"?b2f
this.content = content; Hc8He!X*#
} dJJq]^|
^H1m8=
/** -o`K/f}d
* @return Returns the content.
QJrXn6`
*/ y"'p#j
publicList getContent(){ KF1iYo>p
return content; [)GRP
} -$0}rfX
#\QW <I#/
/** <g;,or#$
* @return Returns the page. e!gNd>b {
*/ _X;,,VEV!
public Page getPage(){ ZeU){CB
return page; 5p S$rf
} ecoI-@CAI
8 sc2r
/** H@$K/
* @param content v~T)g"_|
* The content to set. D6&P9e_5
*/ ]BjYUTNm
public void setContent(List content){ HQ"
trV
this.content = content; }zsIp,
} x>TIx[x
}5(_gYr
/** Cb? !+U
* @param page 8Q<Nl=g>'
* The page to set. R%\3[
*/ -Fn/=
publicvoid setPage(Page page){ '/9j"mIA9$
this.page = page; U:n~S
} ?QJx!'Y,p
} gT$WG$^i
FK~wr;[
b|DU
Sk!' 2y*@&
T&>65`L
2. 编写业务逻辑接口,并实现它(UserManager, r"h09suZBW
24? _k]Y
UserManagerImpl) FZ+2{wIV^
java代码: W,Q>3y*
RMT9tXe*5
DT>`.y%2W
/*Created on 2005-7-15*/ F9K`N8wlu
package com.adt.service; gWa0x-
2)|=+DN;
import net.sf.hibernate.HibernateException; Fs $FR-x
|gP) lR
import org.flyware.util.page.Page; *P/A&"i[E
l9=Ka{$^*
import com.adt.bo.Result; S|k@D2k=
9c k"JMla
/** Dbj?l;'1
* @author Joa -bOtF%
*/ CkNR{?S
publicinterface UserManager { yx-"&K=`
:LNZC,-f}5
public Result listUser(Page page)throws Is3Y>oX
cyB+(jLHDs
HibernateException; XIbxi
85Yi2+8f4
} '[F`!X
hp2E! C ma
bF_0',W
!h7:rv/
*qSvSY*
java代码: zx=eqN@!@
m)pHCS
[|eIax xR,
/*Created on 2005-7-15*/ XdV>6<gf{
package com.adt.service.impl; !wpK
+.D
mkyYs[
import java.util.List; lV^:2I/
ejkUNCKQt
import net.sf.hibernate.HibernateException; /ZabY
>TCit1yD
import org.flyware.util.page.Page; G`0{31us
import org.flyware.util.page.PageUtil; rCA!b"C2
UsU
Ri
import com.adt.bo.Result; 9(S=0<
import com.adt.dao.UserDAO; [9Rh" H;h
import com.adt.exception.ObjectNotFoundException; JJWPte/
import com.adt.service.UserManager; r`6f
t855|
/** R"O%##Ws
* @author Joa ]f&]E
~i
*/ K3
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publicclass UserManagerImpl implements UserManager { ~< UYJc
SWI\;:k
private UserDAO userDAO; dazML|1ow
6 *S/frE
/** *#}=>, v
* @param userDAO The userDAO to set. GiuE\J9i
*/ (EWGX |QA
publicvoid setUserDAO(UserDAO userDAO){ E`^D9:3:)
this.userDAO = userDAO; 45.g ;
} TK'
5NM+4
(VN'1a (
/* (non-Javadoc) oz{X"jfu
* @see com.adt.service.UserManager#listUser Ar/P%$Zfq
W[)HFh(#
(org.flyware.util.page.Page) hkb\GcOj
*/ }DjVZ48
public Result listUser(Page page)throws vqf}(/.D
$+44US
HibernateException, ObjectNotFoundException { 13v`rK`7o
int totalRecords = userDAO.getUserCount(); N-F&=u}
if(totalRecords == 0) 1/:vFX
throw new ObjectNotFoundException 6-"tQ,AZ
diM*jN#
("userNotExist"); s-WZ3g
page = PageUtil.createPage(page, totalRecords); jJ<&!=
List users = userDAO.getUserByPage(page); LA\3 ,Uv
returnnew Result(page, users); V(ww
F
} l6WEx
-d
DIQ30(MS
} iH-,l
2RNee@!JJP
p2b~k[
<#M1I!R
Y&=DjKoVh
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 e#mf{1&
^znUf4N1
询,接下来编写UserDAO的代码: jmq^98jB
3. UserDAO 和 UserDAOImpl: &glh >9:G
java代码: Pz2Q]}(w
b1IAp >*2l
]JGq{I>%+6
/*Created on 2005-7-15*/ jsgDJ}
package com.adt.dao; }E(w@&
(_}q>3
import java.util.List; B:v_5e\f@
!F}GSDDV*
import org.flyware.util.page.Page; ?F[_5ls|]
D}!YF~
import net.sf.hibernate.HibernateException; r]\[G6mE%
p{GO-gE@
/** qlPIxd
* @author Joa ]-#/wC[$l=
*/ _ti^i\8~
publicinterface UserDAO extends BaseDAO { xh#_K@ 8
4x+[?fw
publicList getUserByName(String name)throws PuZzl%i
P3
y7#+VF`xf
HibernateException; ip'{@1L
4NaT@68p
publicint getUserCount()throws HibernateException; /K!f3o+
K9&Q@3V
publicList getUserByPage(Page page)throws X{!,j}
.tfal9
HibernateException; Pr%KcR ;
ak:f4dEd
} ;
Gv-$0{P3
='kCY}dkO
ckP AH E@
16I[z+RG
9&^5!R8
java代码: yCkc3s|DA;
J#@+1 Nt
e&ZTRgYdi
/*Created on 2005-7-15*/ a[zVC)N0
package com.adt.dao.impl; 525^/d6v
N|)e {|k
import java.util.List; s-SFu
Z)(#D($-
import org.flyware.util.page.Page; jYAm}_?No
ZWuNl!l>
import net.sf.hibernate.HibernateException; B!)9
>
import net.sf.hibernate.Query; Snmv
3My}u>
import com.adt.dao.UserDAO; j<Pw0?~s6
[N[4\W!!
/** UjJ&P)
* @author Joa p_n$}z
*/ ;QG8@ms|
public class UserDAOImpl extends BaseDAOHibernateImpl 6_yatq5c
~n0Exw(
implements UserDAO { C{l-l`:
NhYUSk ~u
/* (non-Javadoc) Z{#3-O<a+n
* @see com.adt.dao.UserDAO#getUserByName [\Aws^fD_
[Ax:gj
(java.lang.String) n3U|
d+
*/ 4J=6U&b
publicList getUserByName(String name)throws JCZ&TK
nHXPEbq-g
HibernateException { /:\27n
String querySentence = "FROM user in class dKDCJt]t
W>{&"
5
com.adt.po.User WHERE user.name=:name"; >N`,
3;Z
Query query = getSession().createQuery 0%\fm W j
"[z/\l8O
(querySentence); Q-G8Fo%#,E
query.setParameter("name", name); ~tW<]l7
return query.list(); 'MyJw*%b]
} Ya<KMBi3
q]!FFi{w;
/* (non-Javadoc) &DtI+)[|
* @see com.adt.dao.UserDAO#getUserCount() TOP,]N/F
H
*/ dR,a0+!
publicint getUserCount()throws HibernateException { K!>3`[:I"
int count = 0;
}7fzEo`g
String querySentence = "SELECT count(*) FROM b/#<::D `
ib]<;t
user in class com.adt.po.User"; rfgsas{F
Query query = getSession().createQuery -s0J8b
/
)[\+Nc
(querySentence); @LU[po1I
count = ((Integer)query.iterate().next ~Lu,jLKL=[
e+2lus,u6t
()).intValue(); /d}5R@Oy
return count; 0&&P+adk
} -biw{
X^m@*,[s
/* (non-Javadoc) wt_ae|hv
* @see com.adt.dao.UserDAO#getUserByPage ">fRM=fl
chuJj
IY
(org.flyware.util.page.Page) n*|8(fD
*/ /<O9^hA|
publicList getUserByPage(Page page)throws !#olG}#[
GV9pet89yu
HibernateException { [>j.x2=
String querySentence = "FROM user in class x<d ew
:}SR{}]yXs
com.adt.po.User"; %hBw)3;l
Query query = getSession().createQuery %$_?%X0=t
Xh~oDnP
(querySentence); $x+ P)5)
query.setFirstResult(page.getBeginIndex()) &XhxkN$8
.setMaxResults(page.getEveryPage()); 0q1+5
return query.list(); 5rA>2<\pQ
} q7rX4-G$
-/7@ A
} \IR$~
fv>Jn`
aH500
LzB*d
]@}@G[e#[
至此,一个完整的分页程序完成。前台的只需要调用 7d_"4;K)
%a-fxV[
userManager.listUser(page)即可得到一个Page对象和结果集对象 r"5\\ qf5*
oye/tEMG
的综合体,而传入的参数page对象则可以由前台传入,如果用 }4Gn$'e
*Hh*!ePp
webwork,甚至可以直接在配置文件中指定。 hH?ke(&=f
) I.uqG
下面给出一个webwork调用示例: -fK_F6_\]
java代码: $7Lcn9?G
GL&rT&
p1ER<_fp
/*Created on 2005-6-17*/ o3OJI_
v&
package com.adt.action.user; "KY]2v.
bG)6p05Oa
import java.util.List; <&t[E0mU
SQw"mO
import org.apache.commons.logging.Log; K~8!Gh{h]
import org.apache.commons.logging.LogFactory; .d4&s7n0
import org.flyware.util.page.Page; <2+FE/3L
`
-<S13
import com.adt.bo.Result; z`8>$9
import com.adt.service.UserService; V F"c}
import com.opensymphony.xwork.Action; #Pq6q.UB
<|a9r: [
/** 2l8z/o 7v
* @author Joa i}5+\t[Q
*/ 57U;\L;ZmZ
publicclass ListUser implementsAction{ C[JPohm
QVN@B[9
privatestaticfinal Log logger = LogFactory.getLog $)(Zt^
@Z~0!VY
(ListUser.class); Ti5"a<R4m6
1a},(ZcdX
private UserService userService; .noY[P8i
)q%DRLD'G
private Page page; @hOY&
hN1{?PQ
privateList users; j0e1CSE
6rAenK-%
/* Y3luU&'
* (non-Javadoc) w6k^|."
* mw=keY9]
* @see com.opensymphony.xwork.Action#execute() -.vNb!=
*/ IBv9xP]BZ
publicString execute()throwsException{ Sj4 @pMh4
Result result = userService.listUser(page); [#2z=Xg
page = result.getPage(); \88IFE
users = result.getContent(); }e,*'mCC*
return SUCCESS; 9kU|?JE
} js=w!q0)9
ns8I_H
/** XZPq4(,9}
* @return Returns the page. (K>4^E8
*/ d!q)FRzi
public Page getPage(){ wQ9fPOm
return page; }9&~+Q2
} 9t0NO-a
I [v~nY~l`
/** 2`h
* @return Returns the users. =ThacZHb8
*/ zeHs5P8}r
publicList getUsers(){ QEq>zuz5;
return users; e5cvmUF_W
} a 1pa#WC
}Xy<F?Mh
/** EXbhyg
* @param page q^kOyA.
* The page to set. Aj2yAg
*/ km!jxs
publicvoid setPage(Page page){ <UO'&?G
this.page = page; +Tp>3Jh2
} EWoGdH|
c
]&|.~2 &
/** c5tCw3$t
* @param users B976{;QvXV
* The users to set. sBu- \P#
*/ C+c;UzbD
publicvoid setUsers(List users){ t[ ^68]
this.users = users; @{UtS2L
} 9.$k^|~
&]H Y:
/** 62%=%XD
* @param userService tdB<
* The userService to set. ?e!mv}B_
*/ ]W 6!Xw)[
publicvoid setUserService(UserService userService){ }Z}4_/E
this.userService = userService; |B.tBt^
} '>5W`lZ
} $[8GFv
=P<7tsSuoK
&p#.m"Oon
N[AX]gOJ
Q>emyij
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, ;3WVrYe
6N'v`p8
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 N!:&Xz
&7t3D?K'qX
么只需要: ]l4#KI@
java代码: P_ x9:3
ey>V^Fj
r5N.Qt8
<?xml version="1.0"?> zHvG3Ed@
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MHkTN
Kr'5iFK7
1.0//EN" "http://www.opensymphony.com/xwork/xwork- $&iw (BIq
%B'*eBj~fw
1.0.dtd"> -5t.1/
DkGC+Dw
<xwork> %JC-%TRWK
%$L!N-U6
<package name="user" extends="webwork- d@-bt s&3
xA>O4SD
interceptors"> h*9s^`9)
U6@j=|q
<!-- The default interceptor stack name #^fDKM
!4B($]t
--> \vvV=iw
<default-interceptor-ref L<**J\=7M
?oX.$E?(
name="myDefaultWebStack"/> J}cqBk>
I+]q;dF;
<action name="listUser" Wp<4F6C$@
gIfl}Jat
class="com.adt.action.user.ListUser"> "eiZZSz
<param 9'|NF<
=N%;HfUD
name="page.everyPage">10</param> ?tLBEoUmKT
<result y9OxPq.Cy
0HRLTgIC
name="success">/user/user_list.jsp</result> `w
J^
</action> =)GhrWeVi4
B2PjS1z2
</package> t
Tky
ErNL^Se1
</xwork> |i7j}i
b xT|
-~-BQ!!(
ah\yw
A[@xTqs{{
S0 AaJty
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 uIkB&