Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 +Vo}F
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Zm"{V iv]
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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 0{[m%eSK'
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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 JYrY[',u
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分页支持类: ZA Jp%
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java代码: by'DQ 00
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package com.javaeye.common.util; n6*En7IVh
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import java.util.List; Aub]IO~
Di@GY!
publicclass PaginationSupport { N[<H7_/3
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publicfinalstaticint PAGESIZE = 30; p.
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privateint pageSize = PAGESIZE; lz?;#U
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privateList items; DHw&+MY
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privateint totalCount; !@x+q)2
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privateint[] indexes = newint[0]; S#-wl2z
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privateint startIndex = 0; wO:Sg=,
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public PaginationSupport(List items, int 26dUA~|KJ
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totalCount){ \S*$UE]uG
setPageSize(PAGESIZE); ,bM-I2BR
setTotalCount(totalCount); |\dZ'
setItems(items); kaxvPv1
setStartIndex(0); !IC-)C,q
} bae\Zk%`^
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public PaginationSupport(List items, int
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totalCount, int startIndex){ sK"9fU
setPageSize(PAGESIZE); Dy]I8_
setTotalCount(totalCount); >6~k9>nDb<
setItems(items); RrhT'':[
setStartIndex(startIndex); 4\pWB90V
} j
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public PaginationSupport(List items, int (faK+z,*6R
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totalCount, int pageSize, int startIndex){ $B#6tk~u
setPageSize(pageSize); b1gaj"]
setTotalCount(totalCount); \.f}W_OF
setItems(items); 6
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setStartIndex(startIndex); 7_wJpTz
} { F'Kk\f%:
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publicList getItems(){ Wxkx,q?
return items; Nrah;i+H\o
}
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publicvoid setItems(List items){ jSOS}!=
this.items = items; ;uqx@sx ;
} `:wvh(
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publicint getPageSize(){ hKNY+S})g
return pageSize; YC=S5;
} T#
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publicvoid setPageSize(int pageSize){ B_ja&) !s1
this.pageSize = pageSize; .}k(L4T|=
} `k;KBW
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publicint getTotalCount(){ FG%j{_Ez
return totalCount; \dlph
} z305{B:Y
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publicvoid setTotalCount(int totalCount){ >sD4R}\})
if(totalCount > 0){ w-b' LP
this.totalCount = totalCount; '.Ym!r~wL
int count = totalCount / p0{EQT`tMG
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pageSize; Nwc!r(
if(totalCount % pageSize > 0) joXfmHB}
count++; 3Wcy)y>2Ap
indexes = newint[count]; 8ZcU[8r
for(int i = 0; i < count; i++){ J9%@VZut
indexes = pageSize * ++}\v9Er
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i; |!H?+Jj:
} C#i UP|7hh
}else{ H^~.mBP
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this.totalCount = 0; 4KI [D{
}
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} dQgk.k
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publicint[] getIndexes(){ p<`+sf}A:
return indexes; #FYAV%pi
} L{ho*^b
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publicvoid setIndexes(int[] indexes){ 2X88:
this.indexes = indexes; V (rr"K+
} ~u&|G$1!0
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publicint getStartIndex(){ 6QZ5|T ]
return startIndex; ~|Z'l%<Os
} s?3i)Ymr
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publicvoid setStartIndex(int startIndex){ 64j|}wJ$
if(totalCount <= 0) hzY[
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this.startIndex = 0; | A:@&|
elseif(startIndex >= totalCount) Y'`"9Db
this.startIndex = indexes .wK1El{bf
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[indexes.length - 1]; [m'CR 4(|
elseif(startIndex < 0) 2.Yi(r
this.startIndex = 0; [U\(G
else{ p"`%
this.startIndex = indexes u>.y:>
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[startIndex / pageSize]; 99OD=pxQ
} ekQrW%\3
} BF8"rq}r0
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publicint getNextIndex(){ #\4 b:dv
int nextIndex = getStartIndex() + ~^N]yb
uH\kQ9f
pageSize; O\OE0 [[
if(nextIndex >= totalCount) {SG>'KXZ
return getStartIndex(); :Dl%_l
else +`bC%\T8?
return nextIndex; U3#dT2U
} NvtM3
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publicint getPreviousIndex(){ {.k)2{
int previousIndex = getStartIndex() - 7;LO2<|1
h<p3'
pageSize; -NM0LTF
if(previousIndex < 0) hPdx(E)8!d
return0; GlR~%q-jiQ
else rUwE?Ekn/
return previousIndex; o*ANi;1]&B
} %*)2s,8
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} !rTmR@e$/
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抽象业务类 yu&Kh4AP
java代码: 8SnS~._9
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/** 45}v^|Je\
* Created on 2005-7-12 }qC SS<a
*/ H3 m8
package com.javaeye.common.business; 3vJ12=
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import java.io.Serializable; $W!]fcZlB
import java.util.List; [@{0o+.]'H
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import org.hibernate.Criteria; ;R[&pDx
import org.hibernate.HibernateException; +T_ p8W+j
import org.hibernate.Session; o;J;*~g
import org.hibernate.criterion.DetachedCriteria; [{F%LRCo-
import org.hibernate.criterion.Projections; %!.M~5mCd
import t6u-G+}
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org.springframework.orm.hibernate3.HibernateCallback; {^&@gkYY
import pbB2wt
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org.springframework.orm.hibernate3.support.HibernateDaoS :d'65KMi
DBbc|I/[l
upport; LXhaD[1Rb
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import com.javaeye.common.util.PaginationSupport; PM~*|(fA
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public abstract class AbstractManager extends _J"mR]I+
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HibernateDaoSupport { W\ULUK
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privateboolean cacheQueries = false; (iDBhC;/B
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privateString queryCacheRegion; 6S*zzJ.0K
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publicvoid setCacheQueries(boolean LZ&uj{ <
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cacheQueries){ hhq$g{+[
this.cacheQueries = cacheQueries; nN{dORJlx
} QTh0SL
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publicvoid setQueryCacheRegion(String #)i&DJ^Y
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queryCacheRegion){ 5u pShtC
this.queryCacheRegion = 4%bTj,H#
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queryCacheRegion; >_#)3K1y8
} g.*&BXZi
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publicvoid save(finalObject entity){ (Nt[v;BnO
getHibernateTemplate().save(entity); mq`5w)S)\o
} T0L+z/N_m.
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); $,`VUe{
} {(HxG4~
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publicvoid update(finalObject entity){ G^"H*a
getHibernateTemplate().update(entity); BD1K H;
} eJf>"IF-
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publicvoid delete(finalObject entity){ %<S7
getHibernateTemplate().delete(entity); -><QFJ
} O|(o8VS
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publicObject load(finalClass entity, >40
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finalSerializable id){ ||gEs/6-
return getHibernateTemplate().load IuKnM`X
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(entity, id); -,@bA @&
} (1y='L2rj
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publicObject get(finalClass entity, le2/Zs$
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finalSerializable id){ T+BIy|O
return getHibernateTemplate().get ris;Iu^v0
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(entity, id); p[;8
} b.6ZfB,+G
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publicList findAll(finalClass entity){ BGA%"b
return getHibernateTemplate().find("from 5\+EHW!o
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" + entity.getName()); |)';CBb
} 4d6%
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publicList findByNamedQuery(finalString |?|K\UF(Y
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namedQuery){ Ix4 jof6(
return getHibernateTemplate sVlZNj9i"
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().findByNamedQuery(namedQuery); WxDb3l~
} 7n
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publicList findByNamedQuery(finalString query, FB.!`%{
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finalObject parameter){ Yg|l?d"
return getHibernateTemplate w2KWa-BO
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().findByNamedQuery(query, parameter); XzlIW&"uC
} T!&jFy*W
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publicList findByNamedQuery(finalString query, )MMhlcNC
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finalObject[] parameters){ Wu]/(F
return getHibernateTemplate a]{uZGn@i
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().findByNamedQuery(query, parameters); `J]<_0kX}%
} Q;Q
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publicList find(finalString query){ o9~h%&
return getHibernateTemplate().find `6n!$Cxo
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(query); PGMv(}%;
} mC%%)F'Zf
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publicList find(finalString query, finalObject ''%;EW>
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parameter){ %h3L
return getHibernateTemplate().find k>$FT`
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(query, parameter); %e(9-M4*
} P7cge
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public PaginationSupport findPageByCriteria ./';P<)
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(final DetachedCriteria detachedCriteria){ p"g1V7B
return findPageByCriteria CL
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)#)nBM2\
(detachedCriteria, PaginationSupport.PAGESIZE, 0); V>1D1
} y4 dp1<t%
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public PaginationSupport findPageByCriteria J&n ^y
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(final DetachedCriteria detachedCriteria, finalint 'E@2I9Kj
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startIndex){ #:
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return findPageByCriteria C,9)V5!tP2
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(detachedCriteria, PaginationSupport.PAGESIZE, Zj:a-=
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startIndex); 0~(\lkh*!9
} 9"[!EKW
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public PaginationSupport findPageByCriteria -B<O_*wOj
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(final DetachedCriteria detachedCriteria, finalint >cBGw'S
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pageSize, U)SM),bE[
finalint startIndex){ XhQw+j~1.
return(PaginationSupport) z"G`o"4
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getHibernateTemplate().execute(new HibernateCallback(){ r'Hy}HWuF
publicObject doInHibernate mOwWg
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(Session session)throws HibernateException { N8Rm})
Criteria criteria = deR$
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detachedCriteria.getExecutableCriteria(session);
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int totalCount = 2U=/<3;u
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((Integer) criteria.setProjection(Projections.rowCount g,A.Y,})
SJ1w1^#Pz
()).uniqueResult()).intValue(); DBqg_v
criteria.setProjection I
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(null); KK&<Vw|O\
List items = [Ihp\!xqI
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criteria.setFirstResult(startIndex).setMaxResults |V5 $'/Y
q[PD
(pageSize).list(); /}h71V!
PaginationSupport ps = GI 0x>Z+
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new PaginationSupport(items, totalCount, pageSize, A^}i^
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startIndex); p?J~'
return ps; */0vJz%<.M
} Verbmeg&n
}, true); GnSgO-$"
} zhVa.r A
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public List findAllByCriteria(final `<l/GwtAJ
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DetachedCriteria detachedCriteria){ CT$& zEIm
return(List) getHibernateTemplate wGov|[X
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().execute(new HibernateCallback(){ iBGSBSeL&
publicObject doInHibernate 3p?<iVE
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(Session session)throws HibernateException { Q:-%3)g<<
Criteria criteria = Dz"u8 f
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detachedCriteria.getExecutableCriteria(session); PV,kYM6
return criteria.list(); yV 9]_k
} ;~'cITL
}, true); 7G<KrKal
} pmow[e
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public int getCountByCriteria(final Mp^OL7p^^
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DetachedCriteria detachedCriteria){ pJ2:` f<;
Integer count = (Integer) Z1)jRE2dl
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getHibernateTemplate().execute(new HibernateCallback(){ F#!@}K8
publicObject doInHibernate =|qt!gY)Y
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(Session session)throws HibernateException { <WQ<<s@#pb
Criteria criteria = avHD'zU}N
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detachedCriteria.getExecutableCriteria(session); 7\\~xSXh
return L5V'Sr
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criteria.setProjection(Projections.rowCount A4 A6F<
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()).uniqueResult(); >m2<Nl}
} z^ a6%N
}, true); > hDsm;,/
return count.intValue(); K#JabT
} Cu
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用户在web层构造查询条件detachedCriteria,和可选的 aUIc=Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 /IrR,bvA
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PaginationSupport的实例ps。 AihL>a%
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ps.getItems()得到已分页好的结果集 H/p-YtY
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 \CJx=[3(
ps.getStartIndex()当前分页索引 bCE7hutl
ps.getNextIndex()下一页索引 M0Kh>u
ps.getPreviousIndex()上一页索引 fzkCI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ['}^;Y?*o
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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 lEYT{
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一下代码重构了。 MWn L#!
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我把原本我的做法也提供出来供大家讨论吧: aaqd:N)
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首先,为了实现分页查询,我封装了一个Page类: QGbD=c7
java代码: {xBjEhQm
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/*Created on 2005-4-14*/ m`yn9(1Y[
package org.flyware.util.page; 5|~r{w)9
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/** w
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* @author Joa fN"oa>X
* "k6IV&0
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*/ {Hp}F!X$
publicclass Page { NBg>i7KQ
-t~B@%
/** imply if the page has previous page */ ![P(B0Ct/
privateboolean hasPrePage; ~0^,L3M
LA=>g/+i.X
/** imply if the page has next page */ |IcxegE
privateboolean hasNextPage; {Y*]Qc
d*\C^:Z
/** the number of every page */ &TkbnDuYd~
privateint everyPage; <v7KE*#
{OhkuON
/** the total page number */ H-cBXp5z
privateint totalPage; >NOYa3
hRy}G'0
/** the number of current page */ 'd.@4 9
privateint currentPage; t0V_ c'm
}DUDA%U
/** the begin index of the records by the current j]?0}Z*
);uZ4PNK/?
query */ 6U>jU[/
privateint beginIndex; WtdkA Sj
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/** The default constructor */ Y"/UYxCm|&
public Page(){ JbC\l
6:EH5IO
} u<y\iZ[
b%!`fn-;
/** construct the page by everyPage 6P*)rye
* @param everyPage +|"n4iZ!)
* */ /6+%(f}7l
public Page(int everyPage){ B]KLn?zt5
this.everyPage = everyPage; eRx[&-c
} h%w\O Z7
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/** The whole constructor */ 1uge>o&
public Page(boolean hasPrePage, boolean hasNextPage, UWWD8~:
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int everyPage, int totalPage, ~"rwP=<}
int currentPage, int beginIndex){ ISnS;
this.hasPrePage = hasPrePage; x&fCe{5
this.hasNextPage = hasNextPage; sBXk$
this.everyPage = everyPage; ]qza*ba
this.totalPage = totalPage; =ci5&B?
this.currentPage = currentPage; T4}?w
this.beginIndex = beginIndex; o&F.mYnqX
} O+o%C*`K
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/** <K[Zl/7I
* @return qp_ `Fj:
* Returns the beginIndex. ]xLb )Z
*/ >scS wT
publicint getBeginIndex(){ N
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return beginIndex; @[b:([
} ty< tv|p
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/** z3jzpmz
* @param beginIndex S,tVOxs^
* The beginIndex to set. 8m[L]6F(-z
*/ MW[ 4^
publicvoid setBeginIndex(int beginIndex){ yoY)6cn@
this.beginIndex = beginIndex; DF[b?
} u4+uGYr*@
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/** vzm4
* @return P_lcX;O
* Returns the currentPage. >T*g'954xF
*/ 8(f0|@x^
publicint getCurrentPage(){ e/Oj T
return currentPage; kt3#_d^El
} 0?Wf\7
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/** 2[YD&
* @param currentPage taEMr> /
* The currentPage to set. 4qz{D"M
*/ iY'hkr w
publicvoid setCurrentPage(int currentPage){ WAa1H60VkS
this.currentPage = currentPage; w@ylRq
} f$W}d0(F;
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/** !>@V#I
* @return Iy4MMU
* Returns the everyPage. P"~T*Qq-R
*/ }0nB'0|y
publicint getEveryPage(){ _r5Ild@n
return everyPage; %y\7
} nJ#@W b@
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/** h_G7T1;L
* @param everyPage }Z?[Ut
* The everyPage to set. (l_de)N7
*/ r=||sZs
publicvoid setEveryPage(int everyPage){ rtF6Lg
this.everyPage = everyPage; :::f,aCAu
}
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molowPI
/** hJ*E"{xs
* @return *B<I> <'G
* Returns the hasNextPage. BrcXn@tl
*/ BXv)zE=j
publicboolean getHasNextPage(){ ZWW8Hr
return hasNextPage; $K5s)!
} {=4:Tgw
}o:sx/=u_
/** `oWjq6
* @param hasNextPage y]Tn#4 ,/
* The hasNextPage to set. c@B%`6kF
*/ (g:W|hS
publicvoid setHasNextPage(boolean hasNextPage){ <\~#\A=;
this.hasNextPage = hasNextPage; B@v H1T
} ,:4w$!;
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/** knzED~v@(
* @return )-"L4TC)
* Returns the hasPrePage. *dTf(J
*/ lFV|GJ
publicboolean getHasPrePage(){ g uWqHVSs
return hasPrePage; s(.-bjR
} ZxPAu% Y
~ A|*]0,
/** /=(FM
* @param hasPrePage t6e-~
* The hasPrePage to set. v~cW:I
*/ G ]By_
publicvoid setHasPrePage(boolean hasPrePage){ G&3<rT3Ib
this.hasPrePage = hasPrePage; <sB45sNbU`
} qAik$.
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/** 2=M!lB
*
* @return Returns the totalPage. =~m"TQv
* -XG$ 0
*/ h5keYBA
publicint getTotalPage(){ L^s;kkB
return totalPage; 8J1.(Mwb?
} J*C*](
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/** IEf^.Z
* @param totalPage :{Z^ _;Tf
* The totalPage to set. p&l:937
*/ k $&A
publicvoid setTotalPage(int totalPage){ deY<+!
this.totalPage = totalPage; 2A
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} BVp.A]
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} [E7@W[xr
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tp2 _OQAQ
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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 <F
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个PageUtil,负责对Page对象进行构造: bQjHQ"G
java代码: hzo,.hS's
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/*Created on 2005-4-14*/ 0^Cx`xdX:
package org.flyware.util.page; ScKfr
@cGql=t
import org.apache.commons.logging.Log; bM3e7olWS
import org.apache.commons.logging.LogFactory; AR3=G>hO,
liP{Mu/LO
/** e,UgTxZ
* @author Joa ^D[;JV
* i=QhXCM
*/ iUB ni&B
publicclass PageUtil { U .(_n
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privatestaticfinal Log logger = LogFactory.getLog o2jB~}VMl
'=* 5C{
(PageUtil.class); =oDrN7`,B
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/** 4]KceE
* Use the origin page to create a new page H4Ek,m|c
* @param page >E=a~ O
* @param totalRecords O8o18m8UH
* @return &W!@3O{~.
*/ 0O4mA&&!oK
publicstatic Page createPage(Page page, int EtGr&\,
.r'.5RI A
totalRecords){ \0*LfVr;P
return createPage(page.getEveryPage(), a$:N9&P
V= PoQ9d
page.getCurrentPage(), totalRecords); ^]gl#&"D
} {'kL]qLg
pBkPn+@
/** '~J6mojE
* the basic page utils not including exception 3)\qts5
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handler B=`!
* @param everyPage ?,C,q5
T\
* @param currentPage cn:VEF:l
* @param totalRecords 1j,Y
* @return page p\\q[6
*/ `,[c??h
publicstatic Page createPage(int everyPage, int 0in6z
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currentPage, int totalRecords){ W:J00rsv=`
everyPage = getEveryPage(everyPage); MJ08@xGa
currentPage = getCurrentPage(currentPage); JH#+E04#
int beginIndex = getBeginIndex(everyPage, k<H&4Z)d9
@("AkYPj
currentPage); l !v#6#iq
int totalPage = getTotalPage(everyPage, v^G5
N)F
@oNrR$7
totalRecords); ERjf.7)d
boolean hasNextPage = hasNextPage(currentPage, D(|$6J 0
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totalPage); lUd,-
boolean hasPrePage = hasPrePage(currentPage); hd-ds~ve
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returnnew Page(hasPrePage, hasNextPage, my6T@0R
everyPage, totalPage, (eP)>G]
currentPage, H1M>60*
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beginIndex); owhht98y(
} Rim}DfO/
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privatestaticint getEveryPage(int everyPage){ \O~7X0 <W
return everyPage == 0 ? 10 : everyPage; _P:P5H8
} *p^MAk9=
Xy+|D#b
privatestaticint getCurrentPage(int currentPage){ B#yyO>0k]
return currentPage == 0 ? 1 : currentPage; {r)M@@[
} ,P +&-}gn9
is$d<Y&F
privatestaticint getBeginIndex(int everyPage, int m<4Lo0?nS
ZxWV,s&p
currentPage){ Op{Mc$5a
return(currentPage - 1) * everyPage; $@Fj_
N
} j;.&+.
<0m;|Ai'W
privatestaticint getTotalPage(int everyPage, int \Y$NGB=2[
):@B1 yR
totalRecords){ psVRdluS
int totalPage = 0; v5o%y:~
{Xj%JE[V
if(totalRecords % everyPage == 0) T9A5L"-6T
totalPage = totalRecords / everyPage; 8J0tya"z
else I j /J
totalPage = totalRecords / everyPage + 1 ; =g:\R$lQ
jg(A_V
return totalPage; X1"nq]chGy
} zqkmsFH{
1Rh&04O>VL
privatestaticboolean hasPrePage(int currentPage){ tJP(eaqZ
return currentPage == 1 ? false : true; y(A"g3^=
} j3><J
LmE-&
privatestaticboolean hasNextPage(int currentPage, A5b}G
8TZe=sD~cr
int totalPage){ mfvQ]tz_+
return currentPage == totalPage || totalPage == x@=7M'vr%
~cjvo?)&e;
0 ? false : true; DI\sq8J^
} rgCId@R
eMwf'*#
r[x7?cXsW
} 7Fp2=j
X)~-MY*p
iu 'yB
JY,+eD
4/4IZfznX
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。 xjYFTb}!
;z68`P-
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 =3'wHl
_u0dt) $
做法如下: 7o<RvM
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ;/.Z YTD
~U|te _l
的信息,和一个结果集List: _!CH
java代码: RjT[y: !
jv ";?*I6.
`xSXGI
/*Created on 2005-6-13*/ g;pFT
package com.adt.bo; ]x|sTKv2
So:89T
import java.util.List; !v-(O"a
iq#Z\Y(
import org.flyware.util.page.Page; x^"OH
Z&%61jGK
/** wa C%o%fD
* @author Joa VYBl0!t
*/ cmTZ))m
publicclass Result { h4/rw
fp^
g5.Z B@j
private Page page; ]WG\+1x9
<Wd$6
private List content; }\W3a_,v)
7>nA;F
8_
/** !q X7
* The default constructor "elh~K
*/ t`?FSV
public Result(){ Q7C'O @
super(); &Wba2fD
} 8P .! q
U;(&!Ei
/** ~LVa#
* The constructor using fields E-x(5^b"
* w3*JVIQC
* @param page QMIXz[9w
* @param content {XVSHUtw
*/ 2eNm2;
public Result(Page page, List content){ Abl=Ev
this.page = page; B 5?(gb"
this.content = content; ]OVjq?
} by
{~gu
,FTF@h-Cs
/** */1z=
* @return Returns the content. &~j"3G;e
*/ U+K_eEI0_I
publicList getContent(){ * .e^s3q$
return content; +RbCa
c
} aU3&=aN+
M1^pW63
/** qAm%h\
* @return Returns the page. (HTVSC%=
*/ c[5>kQ-nq
public Page getPage(){ vF_?1|*|
return page; 0iYe>u
} ' o5,P/6
n8?gZ` W
/** *"#>Ov>
* @param content GB-=DC6
* The content to set. lY~xoHT;[
*/ ,Zdc
public void setContent(List content){ AOTI&v
this.content = content; Ei#"r\q j_
} 8Hhe&B
e0 D;]
/** !v^D
j']
* @param page K1Tzy=Z9j
* The page to set. x*YJ:t
*/ =$HzEzrw
publicvoid setPage(Page page){ W4N$]D=
this.page = page; 8]0^OSS
} rO-Tr
} }p#S;JZRu+
Hi?],5,/
E_h 9y
$,
=n
r6^DD$X
2. 编写业务逻辑接口,并实现它(UserManager, 0c]Lm?&
6gp3n;D
UserManagerImpl) !_]WUQvV?
java代码: O9opX\9
mFvw s
H}:apRb
/*Created on 2005-7-15*/ 3&}wfK]X
package com.adt.service; /_ LUys/0
7c+u+Yet
import net.sf.hibernate.HibernateException; %3q@\:s
0s4%22
import org.flyware.util.page.Page; j"c"sF\q
r`"
? K]rI
import com.adt.bo.Result; b2Ct^`|M5
kcQ
|Zg
/** m86w{b$8
* @author Joa p<$z!|7m
*/ 8(BLS{-"<
publicinterface UserManager { Q<"zpwHR
f$P pFSY4
public Result listUser(Page page)throws wZ*m
vXyaOZ
HibernateException; A }dl@
;'nu9FU*O
} ?bbguwo~F
]e+S ~me
; LTc4t
9ah,a 4
"5vFa7y
java代码: #w#B'
$ZE OE8.\
]92@&J0w
/*Created on 2005-7-15*/ sR #( \
package com.adt.service.impl; 1(C%/g#"
e`Yx]3;u(
import java.util.List; )u<sEF
Lx2.E1?@
import net.sf.hibernate.HibernateException; Y(<>[8S m
#A?U_32z/2
import org.flyware.util.page.Page; a?@j`@]ZR~
import org.flyware.util.page.PageUtil; kRG-~'f%`
iX~V(~v
import com.adt.bo.Result; O"Ar3>
import com.adt.dao.UserDAO; 0e3aWn
import com.adt.exception.ObjectNotFoundException; C#(4>'
import com.adt.service.UserManager;
stpa2z
W<kJ%42^j
/** Al
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* @author Joa 3pm;?6i6
*/ 1C:lXx$|
publicclass UserManagerImpl implements UserManager { #Jg)HU9
A`IE8@&Z'
private UserDAO userDAO; !30BZM^
1 [dza5
/** (]rtBeT
* @param userDAO The userDAO to set.
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*/ c^I_~OwaE
publicvoid setUserDAO(UserDAO userDAO){ voCQ_~*)9
this.userDAO = userDAO; DN!:Rm uc
} oc>,5 x
)x#^fN~ 7`
/* (non-Javadoc) \Z<' u;
* @see com.adt.service.UserManager#listUser 4K:p
WG<D+P
(org.flyware.util.page.Page) y1f&+y9e
*/ _v<EFal
public Result listUser(Page page)throws +K]kGF
-cEjB%Neo
HibernateException, ObjectNotFoundException { )mJl-u[0+
int totalRecords = userDAO.getUserCount();
4mUQVzV
if(totalRecords == 0) YG<?|AS/
throw new ObjectNotFoundException l[.RnM[v
Fn$EP:>
("userNotExist"); +.5 /4?
page = PageUtil.createPage(page, totalRecords); |no '^
List users = userDAO.getUserByPage(page); *cJ GrLC
returnnew Result(page, users); 9aYCU/3
} ,M5J~Ga
T+RfMEdr
} KZJ;O7'`
aw {?UvL&
;E(%s=i
<SbW
QbN
$D\SueZ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G5?Dt-;I
a";(C,:0
询,接下来编写UserDAO的代码: ma vc$!y
3. UserDAO 和 UserDAOImpl: (?D47^F &
java代码: }n oI2.-#
UC3?XoT\
x-mRPH
/*Created on 2005-7-15*/ u-yQP@^H
package com.adt.dao; %jim] ]<S[
#GY;.,
import java.util.List; -#|J
_6(QbY'JV`
import org.flyware.util.page.Page; *EvnN:
+QqYf1@F
import net.sf.hibernate.HibernateException; p.n+m[
A9!%H6
/** 7;+:J;xf66
* @author Joa D*I%=);B_
*/ 6m|j "m
publicinterface UserDAO extends BaseDAO { Ft#d&
I
vn9_tL&
publicList getUserByName(String name)throws he;&KzEu
MkF:1-=L
HibernateException; YFL9Q<
Ir }r98lz
publicint getUserCount()throws HibernateException; ,?P @ :S<8
%70sS].@
publicList getUserByPage(Page page)throws U8PSJ0ny
EQET:a:g
HibernateException; JFIUD{>fp
YcBY[i0
} %c*azo.
M`-.0
cF7I
m\)z& hv<r
D4?5% s
java代码: M8oI8\6[
H~^am
PTXy:>]M
/*Created on 2005-7-15*/ TLU^ad#9E
package com.adt.dao.impl; _p"nR
h S/oOeG<Y
import java.util.List; 6Xu8~%i
_pnJ/YE
import org.flyware.util.page.Page; Ph'*s{
~q 0)+'
import net.sf.hibernate.HibernateException; qM~ev E$%
import net.sf.hibernate.Query; SxdH%agM
/pt%*;H
import com.adt.dao.UserDAO; \cP\I5IW:s
8%nb1CA
/** .^6"nnfA#
* @author Joa 2;VggPpT
*/ o$8v8="p
public class UserDAOImpl extends BaseDAOHibernateImpl t9685s
q90eB6G0g
implements UserDAO { ],YIEOx6
'8R5?9"
/* (non-Javadoc) m_LW<'
* @see com.adt.dao.UserDAO#getUserByName M^JRHpTn
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(java.lang.String) 2 |
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*/ S-&[Tp+N
publicList getUserByName(String name)throws I0trHrX9
yJkERiJV
HibernateException { 9tvLj5~
String querySentence = "FROM user in class [XK Ke
Bvj-LT=)
com.adt.po.User WHERE user.name=:name"; {%.FIw k
Query query = getSession().createQuery f0] 8/)
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(querySentence); sS/#)/B
query.setParameter("name", name); @.T(\Dq^
return query.list(); `OO=^.-u
} @5+ JXD
]:m>pI*z.
/* (non-Javadoc) d~1Nct$:
* @see com.adt.dao.UserDAO#getUserCount() |-GmW SK_
*/ mZDL=p
publicint getUserCount()throws HibernateException { yNMnByg3?
int count = 0; *u^N_y
String querySentence = "SELECT count(*) FROM b0|q@!z>
i>#[*.|P
user in class com.adt.po.User"; m`l3@Z
Query query = getSession().createQuery ]@)T]
/*\pm!]._^
(querySentence); , v,mBYaU
count = ((Integer)query.iterate().next <8nl}^d5
FjYih>
()).intValue(); ~?TGSD@(
return count; 7714}%Z
} Ta^l1]9.*
H)tnxD0)
/* (non-Javadoc) Cg[]y1Ne
* @see com.adt.dao.UserDAO#getUserByPage ~=qJSb
m2{3j[
(org.flyware.util.page.Page) U+gOojRy{
*/ p_T>"v
publicList getUserByPage(Page page)throws '#K:e
o%_MTCANy
HibernateException { eq+t%
String querySentence = "FROM user in class 1~/?W^ir
{a-bew
com.adt.po.User"; lIPy)25~
Query query = getSession().createQuery Sp8Xka~5*#
d1$3~Xl]
(querySentence); O]rAo
query.setFirstResult(page.getBeginIndex()) \-3\lZ3qj
.setMaxResults(page.getEveryPage()); NfqJ>[}I+
return query.list(); GjlA\R^e
} P[{qp8(g
ns`|G;1vv
} oo sbf#V
/c/t_xB
Y
Y4"r\V
E=!=4"rZF
@*SgeLeL
至此,一个完整的分页程序完成。前台的只需要调用 8;2UP`8s ?
am;)@<8~Q
userManager.listUser(page)即可得到一个Page对象和结果集对象 %%J)@k^vH
Z'sAu#C
的综合体,而传入的参数page对象则可以由前台传入,如果用 ^~~&[wY
8l,`~jvU!*
webwork,甚至可以直接在配置文件中指定。 h#a;(F4_7
pUtd_8
下面给出一个webwork调用示例: Itn7Kl
java代码: OL+dx`Y
0IU>KGJ-0s
PAG.],"D
/*Created on 2005-6-17*/ 0?kaXD
package com.adt.action.user; wcz|Zy
h&Thq52R
import java.util.List; |tL57Wu93
tj:3R$a
import org.apache.commons.logging.Log; ANB@cK_
import org.apache.commons.logging.LogFactory; \\;i
import org.flyware.util.page.Page; <s/n8#i=H
7d&_5Tj:
import com.adt.bo.Result; g3[Zh=+]E
import com.adt.service.UserService; <WXO].^
import com.opensymphony.xwork.Action; U^jxKBq^
Cw`8[)=}o
/** )X*?M?~\
* @author Joa p0Cp\.
*/ .KiJq:$H
publicclass ListUser implementsAction{ WmU5YZ(mAq
WXz'H),R
privatestaticfinal Log logger = LogFactory.getLog ;M,u,KH)/
n#@/A
(ListUser.class); VA4>!t)
J[E_n;d1
private UserService userService; {z)&=v@
{ctEjgiE
private Page page; /7W N,a
W_k;jy_{9
privateList users; 4.]xK2sW
566vjE
/* v=!Ap ; 2L
* (non-Javadoc) WT(inf[
* 6u-@_/O5R3
* @see com.opensymphony.xwork.Action#execute() / S
*/ rGb7p`J
publicString execute()throwsException{ ~" \qX+
Result result = userService.listUser(page); {v&c5B~,\
page = result.getPage(); jG($:>3a@
users = result.getContent(); D(3\m)
return SUCCESS; jDI )iW`P
} 8#% Sq=/+M
Nxk3uF^
/** zJ;K4)"j
* @return Returns the page. HQi57QB
*/ >7@kwj-f)
public Page getPage(){ =+um:*a.
return page; a*4"j2j v
} w)x`zVwO
ogN/zIU+VA
/** z;Pr] *F
* @return Returns the users. ]RYk Y7>`
*/ nya-Io.
publicList getUsers(){ X4<!E#
return users; U?/UW;k[
} (hywT)#+
-[-LR }u
/** |Ad1/>8i
* @param page piIr.]
* The page to set. 3Cq/
o'
*/ Izrf42 >k
publicvoid setPage(Page page){ "=~P&Mi_
this.page = page; Fy4jujP<
} -fF1vJ7L
[~&C6pR
/** npcB+6
* @param users xEK+NKTeV
* The users to set. -ya0!D
*/ C N9lK29F)
publicvoid setUsers(List users){ }z/;^``
this.users = users; rE?(_LI
} RG(m:N
s3m]rC
/** ?h`Ned0P
* @param userService ]7WBoC8
* The userService to set. ?3:OPP`s
*/ e@k`C{{C]o
publicvoid setUserService(UserService userService){ /m,0H)w1
this.userService = userService; _!FM^N}|
} TmS;ybsG
} aQax85
_Q<wb8+/
x<)%Gs}tb
S312h'K
j
,#^<0u+zrF
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, N*t91 X
Sz0M8fYT]
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 [BS3y`c
y^; =+Z
么只需要: uA;3R\6?
java代码: ]+\@_1<ZI
/BWJ)6#H
MWSx8R)PN
<?xml version="1.0"?> `!MyOI`qS
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Peha{]U
U_a)g
X
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8kZ~
v4L#^Jw(^p
1.0.dtd"> j=v 1:E
.8is!TT
<xwork> o l67x
1jZ:@M:
<package name="user" extends="webwork- rI&GM
|
rl)(4ad=
interceptors"> 9GnNL I{
riI0k{
<!-- The default interceptor stack name +Ux)m4}j
NLDmZra
--> =J.)xDx*
<default-interceptor-ref oRM EC7!A0
od>DSn3T
name="myDefaultWebStack"/> fFXG;Q8&
=YX/]g|9K
<action name="listUser" ]ABpOrg
]Jj\**
class="com.adt.action.user.ListUser"> ok5
{c
<param sg12C
SdUtAC2
name="page.everyPage">10</param> S~vbISl
<result ZTG*|
?uUK9*N
name="success">/user/user_list.jsp</result> :W5*fE(i
</action> kr7f<;rmJ
b?-%Uzp<
</package> 5YIiO7@4
ogv86d
</xwork> J'.:l} g!1
]s jFj
uR"srn;^
puS'9Lpp
]I"oS?
GCrh4rxgg
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 |0(Z)s,
b:7;zOtF
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。 i;^
e6A>
LBtVK, ?
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 M;W{A)0i1
9\*xK%T+
CogLo&.
=mCUuY#
\s;]Tg
我写的一个用于分页的类,用了泛型了,hoho y]=v+Q*+
~az6n)
java代码: u;DF$
Y',s|M1})\
UuxWP\~2
package com.intokr.util; TQK>w'L
b@N|sXt&C
import java.util.List; !-r@_tn|
mLD0Lu_Ob3
/** +3vK=d_Va
* 用于分页的类<br> :c,\8n
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Rs)tf|`/
* xZFha=#
* @version 0.01 AW6]S*rh
* @author cheng v:CYf_
*/ '#t"^E2$
public class Paginator<E> { IDzP<u8v
privateint count = 0; // 总记录数 'q1)W'
privateint p = 1; // 页编号 sCaw"{5qc
privateint num = 20; // 每页的记录数 N##T1 Qm)
privateList<E> results = null; // 结果 =KNg "|
<_MQC
/** HhNH"b&