Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XaT9`L<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 V1y"
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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 ffMh2
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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 =eG?O7z&
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。 hM}rf6B
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分页支持类: anDwv
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java代码: mZGAl1`8
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package com.javaeye.common.util; 0*!CJ;%N
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import java.util.List; dkTewT6'
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publicclass PaginationSupport { #4hxbRN
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publicfinalstaticint PAGESIZE = 30; :cDhqBMNr`
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privateint pageSize = PAGESIZE; /S4$qr cM
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privateList items; 8MUY
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privateint totalCount; b4TZnO
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privateint[] indexes = newint[0]; $ =
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privateint startIndex = 0; K)NB{8 _
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public PaginationSupport(List items, int {+D
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totalCount){ <cC 0l-=
setPageSize(PAGESIZE); Djv0]Sm^!
setTotalCount(totalCount); iWCR5c=
setItems(items); BS-nn y
setStartIndex(0); y b 7
} &.dC%
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public PaginationSupport(List items, int 61qs`N=k
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totalCount, int startIndex){ SePPI.n
setPageSize(PAGESIZE); h7],/? s
setTotalCount(totalCount); rHS;wT
setItems(items); ii0{$}eoh
setStartIndex(startIndex); cJb.@8^J
} 8:W,""
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public PaginationSupport(List items, int m}t.E
_8*}S=
totalCount, int pageSize, int startIndex){ ~!PAs_O
setPageSize(pageSize); SZ/}2_;
setTotalCount(totalCount); 9\2<#,R1q
setItems(items); <5Ft3sd
setStartIndex(startIndex); U[l7n3Y=
} PwF
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publicList getItems(){ 4 h}03 oG
return items; W6N3u7mrb
} '.Ww*N
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publicvoid setItems(List items){ !_zp'V]?
this.items = items; U)v['5%
} WCa>~dF>
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publicint getPageSize(){ }>)e~\Tdzb
return pageSize; _e2=BE`W)
} o+9b%I^1V
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publicvoid setPageSize(int pageSize){ 608}-J=3#
this.pageSize = pageSize; c~_nOd
} J<p.J3I
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publicint getTotalCount(){ 0D x,)C
return totalCount; (#|CL/ &
} f9+J}
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publicvoid setTotalCount(int totalCount){ M4%u~Z:4h+
if(totalCount > 0){ uc0 1{t0,
this.totalCount = totalCount; bfjC: "!H
int count = totalCount / 0F"W~OQ6
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pageSize; 7(ni_|$|
if(totalCount % pageSize > 0) [w0@7p"7
count++; ,r=9$i_
indexes = newint[count]; U8f!yXF'
for(int i = 0; i < count; i++){ +XaRwcLC.
indexes = pageSize * ySfot`LQ
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i; .f1
} }OQaQf9V{
}else{ U9?fUS
this.totalCount = 0; % oPt],>
} tl:V8sYTP
} d|P,e;m-
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publicint[] getIndexes(){ VR8 kY&
return indexes; 74[wZDW|(
} SJseP_-
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publicvoid setIndexes(int[] indexes){ <7U\@si4
this.indexes = indexes; LB(I^
} \&{a/e2:S
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publicint getStartIndex(){ >9WJa 5{
return startIndex; SG5GJCkc
} [`F}<L."
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publicvoid setStartIndex(int startIndex){ w^AY= Fc
if(totalCount <= 0) X.q,
this.startIndex = 0; TFfV?rBI
elseif(startIndex >= totalCount) cO8':P5Q
this.startIndex = indexes :.k1="H~@
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[indexes.length - 1]; $;4y2?E
elseif(startIndex < 0) 9<e%('@[
this.startIndex = 0; &:>3tFQSH
else{ W2$MH: j
this.startIndex = indexes O c[F
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[startIndex / pageSize]; j_(DH2D
} &["s/!O1 R
} }?\8%hK"a7
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publicint getNextIndex(){ P{bRRn4Z
int nextIndex = getStartIndex() + GiZv0>*x
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pageSize; <W>T!;4!
if(nextIndex >= totalCount) m{ wk0
return getStartIndex(); 6-fdfU
else pmWt7 }
return nextIndex; 65HP9`5Tm
} F@%`(/^TA
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publicint getPreviousIndex(){ Q[vQT?J7
int previousIndex = getStartIndex() - b p[wr
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pageSize; 5 O't-'
if(previousIndex < 0) <UEta>jj
return0; Kl Kk?6>
else 8gHOs#\
return previousIndex; \&6^c=2=
} @#j?Z7E|
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} +HXR ))X
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抽象业务类 5LX%S .CW
java代码: <dD)>Y.
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/** f?qp*
* Created on 2005-7-12 {^T_m)|n
*/ mA?fCs
package com.javaeye.common.business; 8|"26UwD/
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import java.io.Serializable; tl=H9w&@
import java.util.List; 8ofKj:W]
#Q]^9/;|4n
import org.hibernate.Criteria; NT0im%
import org.hibernate.HibernateException; LmZ"_
import org.hibernate.Session; Y'{F^VxA/
import org.hibernate.criterion.DetachedCriteria; V0/PjD,jP
import org.hibernate.criterion.Projections; Q,m&XpZ
import S;8gX1Uf
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org.springframework.orm.hibernate3.HibernateCallback; 3J_BuMV
import (-[73v-w
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org.springframework.orm.hibernate3.support.HibernateDaoS tkX?iqKQ
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upport; 8#{DBWU
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import com.javaeye.common.util.PaginationSupport; E]0}&YG
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public abstract class AbstractManager extends [["az'Lrk?
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HibernateDaoSupport { Bnfp_SM
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privateboolean cacheQueries = false; 1!=^mu8
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privateString queryCacheRegion; 1PUeU+
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publicvoid setCacheQueries(boolean 8W2oGL6
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cacheQueries){ 0,]m.)ws
this.cacheQueries = cacheQueries; ~QngCg-5q
} Fl}{"eCF8
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publicvoid setQueryCacheRegion(String Fz {T;
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queryCacheRegion){ 'Z8=y[l
this.queryCacheRegion = [vTk*#Cl4
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queryCacheRegion; iF*L-
} I /z`)
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publicvoid save(finalObject entity){ >]<4t06D
getHibernateTemplate().save(entity); UJiy]y
} !dV2:`|+
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publicvoid persist(finalObject entity){ _Q9I
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getHibernateTemplate().save(entity); z=6zc-$y 9
} .z, ot|
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publicvoid update(finalObject entity){ [J8;V|v
getHibernateTemplate().update(entity); 045_0+r"@
} REGk2t.L
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publicvoid delete(finalObject entity){ \~>
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getHibernateTemplate().delete(entity); E<[Y KY
} fZavZ\qU
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publicObject load(finalClass entity, y#{v\h
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finalSerializable id){ `kYcTFk
return getHibernateTemplate().load s3[\&zt
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(entity, id); |"
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} )?;+<,
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publicObject get(finalClass entity, )m$MC25
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finalSerializable id){ )Ah 7
return getHibernateTemplate().get LUzn7FZk
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(entity, id); d:#z{V_
} `t#9
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publicList findAll(finalClass entity){ /8wfI_P>M"
return getHibernateTemplate().find("from X$*]$Ge>
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" + entity.getName()); * /^}
} $'n?V=4
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publicList findByNamedQuery(finalString 9~{,Hj1xE
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namedQuery){ k] A(nr
return getHibernateTemplate ,Bs/.htQj
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().findByNamedQuery(namedQuery); tu' s]3RE
} 4hx4/5[^
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publicList findByNamedQuery(finalString query, # TZ`
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finalObject parameter){ L:\>)6]Ls
return getHibernateTemplate oFKTBH:I
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().findByNamedQuery(query, parameter); t 7D~JAx6
} @rS(3wu_&
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publicList findByNamedQuery(finalString query, #$;}-*
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finalObject[] parameters){ gh `]OxA
return getHibernateTemplate \ #N))gAQ
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().findByNamedQuery(query, parameters); =~TPrO^
} ?&=JGk^eJ
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publicList find(finalString query){ :{9HsF"h0
return getHibernateTemplate().find z@?WhD
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(query); yN/g;bQ
} 1&RB=7.h
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publicList find(finalString query, finalObject =E62N7_`=
(>uA(#Z
parameter){ *i {e$Zv'
return getHibernateTemplate().find B,] AfH
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(query, parameter); =>XjChM
} yO`
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public PaginationSupport findPageByCriteria vxS4YR b
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(final DetachedCriteria detachedCriteria){ A8g_BLj!e
return findPageByCriteria qJE_4/<^!
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); g>
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} J:@yG1VIp
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public PaginationSupport findPageByCriteria mqbCa6>_S
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(final DetachedCriteria detachedCriteria, finalint R$`%<Y3)
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startIndex){ &eb8k2S
return findPageByCriteria s>)?MB*vb
OC)=KV@KE
(detachedCriteria, PaginationSupport.PAGESIZE, `I8ep=VZ
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startIndex); CjEzsjqe<I
} ]Upr<!
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public PaginationSupport findPageByCriteria 4dy!2KZN
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(final DetachedCriteria detachedCriteria, finalint -qBdcbi|x)
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pageSize, y&/bp<Z
finalint startIndex){ MnlD87x@X
return(PaginationSupport) ]WK~`-3C^
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getHibernateTemplate().execute(new HibernateCallback(){ cG&@PO]+.
publicObject doInHibernate ;ik,6_/Y
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(Session session)throws HibernateException { bVzJOBe
Criteria criteria = !ST7@D
@?RaU4e
detachedCriteria.getExecutableCriteria(session); }$[@*
int totalCount = -hq^';,
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((Integer) criteria.setProjection(Projections.rowCount .[+}nA,g%~
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()).uniqueResult()).intValue(); K'B*D*w
criteria.setProjection _GM?`
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(null); ^CgN>-xZ?#
List items = MS:,I?
wp83E,
criteria.setFirstResult(startIndex).setMaxResults Bw~jqDZ}|
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(pageSize).list(); U2LD_-HZ
PaginationSupport ps = rGrR;
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new PaginationSupport(items, totalCount, pageSize, fhyoSRLR:
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startIndex); QNXoAx%I
return ps; .IM]B4m
} 9GsG* $-I
}, true); W)'*Dcd
} xm5?C>vu(
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public List findAllByCriteria(final t/_\w"
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DetachedCriteria detachedCriteria){ = l:k($%%
return(List) getHibernateTemplate maa$kg8U*!
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().execute(new HibernateCallback(){ |Qcj+HH.
publicObject doInHibernate &8yGV i
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(Session session)throws HibernateException { l`uMtv/Wp
Criteria criteria = +
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detachedCriteria.getExecutableCriteria(session); YWJ$Pp
return criteria.list(); "ZPgl 8
} 0FLCN!i1
}, true); V(:wYk?ZR
} 22;B:
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public int getCountByCriteria(final 9_4(}|"N|
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)*
DetachedCriteria detachedCriteria){ A6J:!sY4A
Integer count = (Integer) -ssmj8:Q\|
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getHibernateTemplate().execute(new HibernateCallback(){ `7'^y
publicObject doInHibernate C#8A|
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(Session session)throws HibernateException { EZzR"W/
Criteria criteria = G
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detachedCriteria.getExecutableCriteria(session); ;nJ2i?"
return .C&kWM&j
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criteria.setProjection(Projections.rowCount $|7=$~y
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()).uniqueResult(); cMCM>*X
} x^ `IZ{!
}, true); !* KQ2#e
return count.intValue(); Jw#7b[a
} t: oQHhO?
} gz~ug35
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用户在web层构造查询条件detachedCriteria,和可选的 Z:Vde^Ih
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 I3b*sx$
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PaginationSupport的实例ps。 +IWf~|s
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ps.getItems()得到已分页好的结果集 dG8mE&$g
ps.getIndexes()得到分页索引的数组 c5uC?b].
ps.getTotalCount()得到总结果数 *4LRdLMn
ps.getStartIndex()当前分页索引 O*bzp-6\
ps.getNextIndex()下一页索引 Z{:;LC
ps.getPreviousIndex()上一页索引 RZKx!X4=q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {\NBNg(Vo
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 =
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一下代码重构了。 J]w3iYK
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我把原本我的做法也提供出来供大家讨论吧: lkly2|wA
BlZB8KI~
首先,为了实现分页查询,我封装了一个Page类: a7uL{*ZR
java代码: jIwN,H1$-
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/*Created on 2005-4-14*/ Yk)fBPHr
package org.flyware.util.page; 8DMqjt3B
m/jyc#
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/** %'=2Jy6h
* @author Joa "KS"[i!3j
* <#;5)!gr{
*/ Mk=*2=d
publicclass Page { h-sO7M0E]
->o[ S0
/** imply if the page has previous page */ r$-P
privateboolean hasPrePage; E2t&@t%W
6J#R1.h
/** imply if the page has next page */ q*,HN(&l?
privateboolean hasNextPage; nd,\<}uP9
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/** the number of every page */ W(Md0*
privateint everyPage; =hd0Ui>x
t Zm`(2S
/** the total page number */ +5I'? _{V
privateint totalPage; e==/+
#Ef! X
/** the number of current page */ n7Bv~?DM
privateint currentPage; mF!4*k
%Tu(>vnuj
/** the begin index of the records by the current Y~Vc|zM^(
|pbetA4&
query */ iOCs%J
privateint beginIndex; p:$kX9mT&
zHg=K /
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/** The default constructor */ ZR%$f-
public Page(){ ;&f(7 Q+T_
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} %.wR@9?
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/** construct the page by everyPage O"kb*//
* @param everyPage :is2 &-|x
* */ |uz\XK
public Page(int everyPage){ ` ~^ My~f
this.everyPage = everyPage; w-$iKtb.
} (x@J@ GP*
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/** The whole constructor */ _Gt;=
public Page(boolean hasPrePage, boolean hasNextPage, i `p1e5$
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0
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int everyPage, int totalPage, =sv?))b`
int currentPage, int beginIndex){ Nu3IYS5&
this.hasPrePage = hasPrePage; $%!06w#u
this.hasNextPage = hasNextPage; <n2'm
this.everyPage = everyPage; b{)kup
this.totalPage = totalPage; qmGHuQVe
this.currentPage = currentPage; 6I=xjgwvf
this.beginIndex = beginIndex; . XbDb
} 8.^`~ta
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/** ]B8iQr-!
* @return )?B-en\
* Returns the beginIndex. $I/ !vV
*/ v$x)$/]n
publicint getBeginIndex(){ ^_V0irv
return beginIndex; .I]v
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} "'+C%
d(d3@b4Ta
/** z.\\m;s
* @param beginIndex y!:vX6l
* The beginIndex to set. zFipuG02
*/ \L$]2"/v-
publicvoid setBeginIndex(int beginIndex){ 8tf>G(I{
this.beginIndex = beginIndex; ]]`[tVaFr
} {R[ V
RhT:]
/** K4E2W9h
* @return #lSGH 5Fp?
* Returns the currentPage. >gq=W5vN(
*/ 8'zfq
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publicint getCurrentPage(){ &U=_:]/
return currentPage;
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} hCc%d$wVk
x*tCm8`{
/**
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* @param currentPage =w8 0y'
* The currentPage to set. lA4J#
*/ 38l:Y"
publicvoid setCurrentPage(int currentPage){ xiQc\k$
this.currentPage = currentPage; "?<`]WG\
} /#"9!8%V
>b#CR/^z
/** X}h}3+V
* @return fpjFO&ML
* Returns the everyPage. .wWf#bB
*/ TV_a(#S
publicint getEveryPage(){ =>Z4vWX*
return everyPage; n}1hmAhZ
} qh&KNJ>1
+!`$(
/** Ln+ k_
* @param everyPage *!Gb_!98
* The everyPage to set. ~R=p[h)
*/ Eg&Q,dH[
publicvoid setEveryPage(int everyPage){ 4\ )WMP
this.everyPage = everyPage; 'u%_Ab_H
} 5^l-3s?M
2\O!vp>|-
/** =*6frC~
* @return dvY3=~'
* Returns the hasNextPage. sT<h+[2d
*/ '&gUAt
publicboolean getHasNextPage(){ j\Fbi3H
return hasNextPage; $(OL#>9Ly
} G%i&C)jZ
!^1oH**
/** @^-f+o
* @param hasNextPage (U.VCSn
* The hasNextPage to set. nHfAx/9!
*/ h]|2b0
publicvoid setHasNextPage(boolean hasNextPage){ K&dc< 4DC
this.hasNextPage = hasNextPage; u8<Fk
!
} uV'C_H
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/** n4"xVDL
* @return eSMno_Gt3
* Returns the hasPrePage. ^;\6ju2
*/ .>y3`,0h
publicboolean getHasPrePage(){ +_f813$C
return hasPrePage;
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} {cw+kY]m4-
eR3MU]zF
/** +K;%sAZy
* @param hasPrePage ms+gq
* The hasPrePage to set. OQyZ'
*/ 3A\Hiy!{F
publicvoid setHasPrePage(boolean hasPrePage){ Lr"`OzDz
this.hasPrePage = hasPrePage; pf=CP%L
} {gDoktC@M
O7,:-5h0
/** $uK[[k~=S
* @return Returns the totalPage. E`iE]O
* lx82:_
*/ 5(Xq58nhxI
publicint getTotalPage(){ gJ$m'kC;
return totalPage; 5y~B/.YY
} 1py>[II@
%.{xo.`a[
/** z KG]7
* @param totalPage gvP.\,U
* The totalPage to set. ^c sOXP=Yp
*/ 8Y;>3zth7
publicvoid setTotalPage(int totalPage){ ,/Y$%.Rp
this.totalPage = totalPage; '}P$hP_d
} R_:-Z.
zfGr1;
} a -5#8
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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 6". v6
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个PageUtil,负责对Page对象进行构造: FvBnmYnW
java代码: %-NG eN8
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7bkh")^
/*Created on 2005-4-14*/ j2%#xZ{33
package org.flyware.util.page; mi sPJO&QD
DJR r
import org.apache.commons.logging.Log; #)KQ-x,
import org.apache.commons.logging.LogFactory; P?iQ{x}w~
-9"[/
/** (i^<er q
* @author Joa k,[[
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* 8.' THLI
*/ `SYq/6$VEH
publicclass PageUtil { NbhQ-
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privatestaticfinal Log logger = LogFactory.getLog v,c:cKj
88atj+N]
(PageUtil.class); LO,k'gg<
"I[uD)$
/** {_J1m&/
* Use the origin page to create a new page !f8]gT zN
* @param page 4({Wipd
* @param totalRecords y@]:7
* @return G\S_e7$/
*/ rJcZ a#
publicstatic Page createPage(Page page, int dxWG+S
8d\/
totalRecords){ "& q])3h =
return createPage(page.getEveryPage(), J`A )WsKkb
xgB-m[Xi
page.getCurrentPage(), totalRecords); G/}nwj\
} K6oQx)|
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/** +}!FP3KgT
* the basic page utils not including exception |f"1I4Kg
lO^YAOY
handler K>`*JJ,
* @param everyPage 0]t7(P"F6
* @param currentPage dIvvJk8
* @param totalRecords T9Pu V
* @return page ? `#
*/ Tn\59 (
publicstatic Page createPage(int everyPage, int TZS:(MJ9M
u]QG^1.qYe
currentPage, int totalRecords){ JztSP?
everyPage = getEveryPage(everyPage); I-|1eR+3
currentPage = getCurrentPage(currentPage); EoHrXv
int beginIndex = getBeginIndex(everyPage, a/p
/<
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currentPage); Q!}LtR$
int totalPage = getTotalPage(everyPage, hk+"c^g:j<
si>gYO
totalRecords); {DGnh1
boolean hasNextPage = hasNextPage(currentPage, *[wj )
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totalPage); WzO[-csy
boolean hasPrePage = hasPrePage(currentPage); V]A*' ke/
1ba* U~OEg
returnnew Page(hasPrePage, hasNextPage, ?O#,|\v?]
everyPage, totalPage, V']1j
currentPage, u-#J!Z<T8
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beginIndex); a6.0$'
} ^>!~%Vv7!
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privatestaticint getEveryPage(int everyPage){ 3gU*,K7
return everyPage == 0 ? 10 : everyPage; R//S(eU68\
} _8nT$!\\
+h?z7ZY^
privatestaticint getCurrentPage(int currentPage){ _f~m&="T!
return currentPage == 0 ? 1 : currentPage; 3D"?|rd~
} Fo[=Dh*AqU
!3Me
6&$O
privatestaticint getBeginIndex(int everyPage, int p3z%Y$!Tm
N"o+;yR
currentPage){ d7Devs
k
return(currentPage - 1) * everyPage; =OF]xpI'&a
} ^G]H9qY-e
D<XRu4^;
privatestaticint getTotalPage(int everyPage, int y5lhmbl: e
/2e,,)4g
totalRecords){ dW>$C_`?
int totalPage = 0; ;tu2}1#r
?>o|H-R~5Z
if(totalRecords % everyPage == 0) +c_8~C
totalPage = totalRecords / everyPage; [}bPkD
else 7FD.3/
totalPage = totalRecords / everyPage + 1 ; Luu.p<
#sp8 !8|y
return totalPage; 2XGbqZj
} i5^U1K\M
0}y-DCuQ
privatestaticboolean hasPrePage(int currentPage){ |F^h>^
x
return currentPage == 1 ? false : true; %oEvp{I
} x$\w^h\F
h|t\rV^
privatestaticboolean hasNextPage(int currentPage, ~`Xu6+1o
xK C{P{:
int totalPage){ @Tg +Kt
return currentPage == totalPage || totalPage == iKN800^u
ck4g=QpD{
0 ? false : true; /C)FS?=
} X mX
.)h'Y
G@;I^_gN
PFnq:G^L
} ;Q} H'Wg,
4Gm (P~N
9,zM.g9Qv
K+s
xO/}h
8cyC\Rs
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。 =)Q0=!%-
Fq9>t/Zj
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 !u=,b fyH
N`%f+eT(
做法如下: =c(3EI'w
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Kp_^ 2V?
fnm:Wa|,%|
的信息,和一个结果集List: IB+)2 `
java代码: vs~lyM/
r 2L=gI
D1VM_O
/*Created on 2005-6-13*/ Co#_Cyxg=9
package com.adt.bo; #yVMC;J?W
/i)1BaF
import java.util.List; k|c=O6GO
qEbzF#a-:
import org.flyware.util.page.Page; 3V`.<
_z3YB
/** 4C{3>BE
* @author Joa edy6WzxBcm
*/ P?P))UB5
publicclass Result { Ho:X.Z9A^
!1\jD
private Page page; DfQD!}=
az2CFd^M
private List content; XUyoZl?
a\PvRW*I
/** M :Aik&
* The default constructor JKsdPW<?
*/ p-t*?p
C
public Result(){ +2+wNFU
super(); .4NQ2k1io
} rX<gcntv
.5~W3v
<
/** X519}
l3
* The constructor using fields Qb;5:U/x
* g6. =(je
* @param page \!tS|h
* @param content Lx"a #rZ
*/ mTW@E#)n
public Result(Page page, List content){ `1[GY){?)
this.page = page; bu2'JIDR
this.content = content; t[ZumQ@HC
} !F|iL
k5@_8Rc
/** dIR6dI
* @return Returns the content. =abth6#)
*/ )*Qa9+:
publicList getContent(){ rGe^$!QB
return content; ^{W#ut>IN
} :tA|g
Um$a9S8b&
/** ymsqJ
* @return Returns the page. Mwdw7MZ"S
*/ 69v[*InSd
public Page getPage(){ ]cv|A^
return page; 0+\~^
} ?Ze3t5Ll
",ic"
~
/** Nv
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* @param content ZREAEGi{
* The content to set. H5N(MihT
*/ dIo|i,-
public void setContent(List content){ nAp7X-t
this.content = content; 4D/mm(2d$
} >)N}V'9
Lz
VvUVk
/** RhJL`>W`
* @param page "F+Wo&
* The page to set. Yb|zE
*/ %V$ujun`
publicvoid setPage(Page page){ N!fp;jvG
this.page = page; TLL.Ch|#Y
} e< Ee2pGX
} Z6cG<,DQ
YSuwV)Y
(8r?'H8ZO
IpxFME%!
Q#bFW?>y,
2. 编写业务逻辑接口,并实现它(UserManager, )W@H
o4kNDXP#S
UserManagerImpl) m,u?
^W
java代码: >oc7=F<8lS
Lh &L5p7
c3lfmTT6^
/*Created on 2005-7-15*/ |yI?}zyR
package com.adt.service; w?AE8n$8
Oz9k.[j(
import net.sf.hibernate.HibernateException; ubhem(p#
oh;F]*k6
import org.flyware.util.page.Page; r,6~?hG]
EMH?z2iGd
import com.adt.bo.Result; `.dTkL
^}8_tZs8\
/** f (
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* @author Joa )^!-Aj\x
*/ U[S;5xeF.j
publicinterface UserManager { Ze$:-7Czl
7l Aa6"Y68
public Result listUser(Page page)throws P|.KMtG
2597#O
HibernateException; >t8eVMMa
r/Pg,si
} S$"A[
7$GP#V1r/
@fpxGMy&
"`:#sF9S
qc\o>$-:`
java代码: }7$\F!R
!*%3um
!9o8v0ZI
/*Created on 2005-7-15*/ )K2n!Fbd
package com.adt.service.impl; NUL~zb
#G#gB
import java.util.List; p,D/ Pb8
I{cn ,,8
import net.sf.hibernate.HibernateException; ecf7g)+C
4r(rWlM
import org.flyware.util.page.Page; l}AB):<Z
import org.flyware.util.page.PageUtil; ^:-%tpB#!
nTu"
import com.adt.bo.Result; oS_p/$F,
import com.adt.dao.UserDAO; <R{\pz2w
import com.adt.exception.ObjectNotFoundException; 8}\"LXRbo
import com.adt.service.UserManager; &P ;6P4x
sCb?TyN'n
/** "<O?KO3K
* @author Joa m Xw1%w[*
*/ !9)*. 9[8
publicclass UserManagerImpl implements UserManager { dy`~%lX?
1xtbhk]D
private UserDAO userDAO; gdC=SFb b
)QZ?Bf
/** "Ln\ZYB]
* @param userDAO The userDAO to set. C1G Wi4)
*/ &2\.6rb.
publicvoid setUserDAO(UserDAO userDAO){ y6jTT%
this.userDAO = userDAO; 2N,*S
} 0\Oeo8<7)~
R1q04Zj{2
/* (non-Javadoc) xDlC]loi7
* @see com.adt.service.UserManager#listUser :,VyOmf
3YT _GW{
(org.flyware.util.page.Page) 'ZDa *9nkF
*/ eB]ZnJ2^=
public Result listUser(Page page)throws \aW5V: ?
Hh@mIusj
HibernateException, ObjectNotFoundException { v5$zz w
int totalRecords = userDAO.getUserCount(); A`r&"i OKA
if(totalRecords == 0) Y2$%%@
throw new ObjectNotFoundException jN {ED_
b'{D4/
("userNotExist"); YT:5J%"
page = PageUtil.createPage(page, totalRecords); .HtDcGp
List users = userDAO.getUserByPage(page); 9Pb0Olh
returnnew Result(page, users); vOP[ND=T
} MoFZ
|]]fcJOBP
}
xjX5 PQu
WD)[Ac[
c&_3"2:
gh
0\9;h
/V*eAn8>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [}AcCXg`L
3?}SXmA'@
询,接下来编写UserDAO的代码: |F=^Cu,
3. UserDAO 和 UserDAOImpl: 0CN.gu
java代码: W4| ;JmT.r
0bd.ess
0s4j>
/*Created on 2005-7-15*/
^Ta"Uk'
package com.adt.dao; 1IsR}uLh
*LhR$(F(
import java.util.List; )i>KYg w
4i19HD_
import org.flyware.util.page.Page; 5y~[2jB:
UmJg-~
import net.sf.hibernate.HibernateException; B=p'2lla
><DE1tG
/** C eg6o&^
* @author Joa u@|yw)
*/ %q!nTGU~
publicinterface UserDAO extends BaseDAO { @rdC/=Y[
A6Qi^TI
publicList getUserByName(String name)throws 4@Qq5kpk*
l-npz)EM
HibernateException; }Ag2c; aaq
2-CK:)n/#
publicint getUserCount()throws HibernateException; 2]'ozs$|v
OL=b hZ
publicList getUserByPage(Page page)throws 9!OpW:bR|
`<Ftn
HibernateException; K4tX4U[Z
D *tBbV
} 5u!cA4e"
uJ$"2<O
SW=p5@Hy{
f;Dz(~hw
XU54skN
java代码: 93rE5eGs
_\<M58/z
+l#2u#e
/*Created on 2005-7-15*/ !`Wu LhB`
package com.adt.dao.impl; .6hH}BM
Mu%'cwp$
import java.util.List; 8BN'fWl&E
Psv!`K
import org.flyware.util.page.Page; x{- caOH
+1y#=iM{
import net.sf.hibernate.HibernateException; {xr]xcM'b
import net.sf.hibernate.Query; F,bl>;{[{
t>[r88v
import com.adt.dao.UserDAO; h
Na<LZ
wVVe L$28
/** AjS5
* @author Joa oMVwIdf
*/ 4M]8po/;
public class UserDAOImpl extends BaseDAOHibernateImpl )<|T Ep4r-
N4:'X6u;
implements UserDAO { : ?V;
#.@=xhK/
/* (non-Javadoc) o6r4tpiR5
* @see com.adt.dao.UserDAO#getUserByName `#]\Wnp~y
Dn[1BWM/7
(java.lang.String) `4=b|N+b"
*/ JjmL6(*ui
publicList getUserByName(String name)throws ymzm x$o=
S;NXOsSu
HibernateException { HT&0i,`
String querySentence = "FROM user in class zxh"@j$?
=
` ^jz}
com.adt.po.User WHERE user.name=:name"; gr;M
Query query = getSession().createQuery NR*SEbUU*
7I|%GA_
(querySentence); g U?)
query.setParameter("name", name); 1 W0; YcT]
return query.list(); 0D'Wr(U(
} |^F-.Z
eZ!k'bS=
/* (non-Javadoc) Vo%d;>!G\;
* @see com.adt.dao.UserDAO#getUserCount() $o/>wgQY-
*/ @2mP
publicint getUserCount()throws HibernateException { &0g,Xkr
int count = 0; g|P hNo
String querySentence = "SELECT count(*) FROM 1@WGbORc*
82X.
user in class com.adt.po.User"; Y8PT`7gd`
Query query = getSession().createQuery R+K[/AA
#RF=a7&F
(querySentence); ^6+x0[13
count = ((Integer)query.iterate().next #jX>FXo
xYT.J 6
()).intValue(); &Yg/08*
return count; wGvgMZ ]?'
} AV p[gr
+RkYW*|$S
/* (non-Javadoc) H[D/Sz5`
* @see com.adt.dao.UserDAO#getUserByPage ]c)SVn$6
x}{VHp`|ld
(org.flyware.util.page.Page) h,x]
*/ Al|7Y/
publicList getUserByPage(Page page)throws ca=e_sg
gNwXOd u
HibernateException { .6K>"
String querySentence = "FROM user in class o$O,#^
=lwS\mNs
com.adt.po.User"; K +~v<F
Query query = getSession().createQuery #lF<="y%X
K(gj6SrjV
(querySentence); i.sq^]j
query.setFirstResult(page.getBeginIndex()) HhvG#Sam!
.setMaxResults(page.getEveryPage()); {<kG{i/
return query.list(); z (3"\ ^T
} 8|({
_Z
vrzX%'
}
`xUPML-
-Q6pV<i
f[b YjIX
T Rw6$CR
6<Z:Xw
至此,一个完整的分页程序完成。前台的只需要调用 [fp"MPP3
$J6.a!5IE
userManager.listUser(page)即可得到一个Page对象和结果集对象 LzRiiP^q
\#aVu^`eX
的综合体,而传入的参数page对象则可以由前台传入,如果用 ?^~"x.<nr
yUO|3ONT
webwork,甚至可以直接在配置文件中指定。 NJ>p8P`_k
oui!fTy
下面给出一个webwork调用示例: D,\=zX;
java代码: _sVs6AJ
$]kg_l)
[.X%:H+
/*Created on 2005-6-17*/ U[b;#Y1X
package com.adt.action.user; ]ufW61W6Ci
bSf(DSqx
import java.util.List; %v[Kk-d
\w^QHX1+
import org.apache.commons.logging.Log; FRFAWK<
import org.apache.commons.logging.LogFactory; au|^V^m
import org.flyware.util.page.Page; 9Yyg}l:
U$)Hhn|X
import com.adt.bo.Result; C8E C?fSQ
import com.adt.service.UserService; N;'HR)
import com.opensymphony.xwork.Action; s.` d<(X?
gE&W6z0fJ
/** G%!\ p:w
* @author Joa vo(NB
!x$
*/ JtpY][}"~3
publicclass ListUser implementsAction{ L\NZDkd
S |>$0P4W(
privatestaticfinal Log logger = LogFactory.getLog 7E`(8i
hFMst%:y$
(ListUser.class); V:BX"$J1
AwUc{h l<
private UserService userService; \oX8/-0 f
R: <@+z^A[
private Page page; _-]!;0EIV
4|N\Q=,
privateList users; o^Yspp
vQ"s
/* -fJ@R1]
* (non-Javadoc) ~AanU1U<
* i ,pN1_-
* @see com.opensymphony.xwork.Action#execute() O[)]dD&'
*/ tvT8UW'
publicString execute()throwsException{ c%@~%IGF
Result result = userService.listUser(page); i 1I>RK
page = result.getPage(); &_d/ciq1f
users = result.getContent(); GWhAjL/N
return SUCCESS; $-Pqs
^g
} >}b6J7_
_1<'"u#6w
/** ,|X+/|gm
* @return Returns the page. BD7@Mj*|
*/ mO)PJd2ZD
public Page getPage(){ pXh~#o6V
return page; K\+}q{
} .^lbLN^2
HI\f>U
/** eQFb$C]R}y
* @return Returns the users. _/}Hqh
*/ vM7v f6
publicList getUsers(){ Y#&0x_Z
return users; {Mr~%y4
} ^2^|AXNES
i9eyrl+!
/** s
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* @param page ydND$@; Z
* The page to set. s!ZW'`4!z
*/ z8/xGQn
publicvoid setPage(Page page){ pp]_/46nN
this.page = page; <*"pra{3
} OR\DTLIl
K-
I\P6R`
/** D!}K)T1~R
* @param users /.)[9bQ<
* The users to set. ]hE+$sKd
*/ .S!>9X,
publicvoid setUsers(List users){ 5m^Hi}S_
this.users = users; a-5HIY5
} "f|(@a
pAil]f6
/** 58&{5YpS
* @param userService E8-fW\!F
* The userService to set. ?#m<\]S<
*/ AL]h|)6QpC
publicvoid setUserService(UserService userService){ pSQCT
this.userService = userService; yYToiW *
} n<?SZ^X{,/
} T+WZE
m0j|58~
=1*%>K
W&e'3gk _
cRh\USS
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, C~{NKMeC/m
H5Ux.]y
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 .vN%UNu
6!+X.+
么只需要: ^+*GbY$'
java代码: 1GG>.RCP
^r>f2 x
}2ql?K
<?xml version="1.0"?> m\/,cc@,
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 7k[pvd|L
p9AZ9xr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- RQ^m6)BTo
CYt jY~
1.0.dtd"> |
"Jx
@%OPy|=,{
<xwork> mA(nyF
"mPSA Z
<package name="user" extends="webwork- mPs%ZC
4<T*i{[
interceptors"> wfBuU>
7deAr$?Wx
<!-- The default interceptor stack name -c+[6A>j
>-5td=:Z
--> s>jr1~~3O_
<default-interceptor-ref X-kXg)!Bg
]6{(Hjt
name="myDefaultWebStack"/> _BG8/"h32
&so-O90
<action name="listUser" -RG8<bI,
g.I(WJX0
class="com.adt.action.user.ListUser"> -ca7x`yo
<param /a[V!<"R
y]}b?R~p=
name="page.everyPage">10</param> W/ g|{t[
<result e9CP802#2
^W
Y8-6
name="success">/user/user_list.jsp</result> h@*lWi2K7
</action> qDnCn H
nnt8 sf@\
</package> O87"[c`>
{ p1lae
</xwork> bz{^ h'
j)jCu ;`
<nDNiM#
[ rQMD^:M$
}#yU'#|d
C=N!z
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 rO/a,vV
"^;#f+0
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 P<%v+O
&Nc[$H7<
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )@}A
r
}m6f^fs}
,~(|p`
QVIcb;&:}
lij B#1<8*
我写的一个用于分页的类,用了泛型了,hoho tNK^z7Dm
oW0gU?Rr)u
java代码: Q |
,{k<JA{
~?#~ Ar
package com.intokr.util; m</]D WJ
}>2t&+v+
import java.util.List; WgE@8 9
NW
z9C=y
/** N0+hejz
* 用于分页的类<br> Da-u-_~
* 可以用于传递查询的结果也可以用于传送查询的参数<br> B@-|b
* A9
U5,mOz
* @version 0.01 k+FMZ,D|
* @author cheng s(t eQ\
*/ p-.Ri^p
public class Paginator<E> { cZqfz
privateint count = 0; // 总记录数 *kP;{Cb`
privateint p = 1; // 页编号 8tU>DJ}0
privateint num = 20; // 每页的记录数 "tqnx?pM
privateList<E> results = null; // 结果 HmvsYP66
hM?`x(P
/** Hi^35
* 结果总数 *oCxof9JA
*/ 14mf}"z\
publicint getCount(){ >K\3*]>J3
return count; Nepi|{
} BU`ckK\(
)X/*($SuA
publicvoid setCount(int count){ >tN5vWW
this.count = count; wHf&R3fg
} S+r^B?a<oM
DKX/W+#a
/** W3)\co
* 本结果所在的页码,从1开始 7%e1cI
* TN5>" ??"
* @return Returns the pageNo. oz LH ]*
*/ +jUgx;u,
publicint getP(){ ]D O&x+Rb
return p; e,(a6X
} I?B,sl_w
80C(H!^
/** ML=eL*}l
* if(p<=0) p=1 zX98c
* wTxbDT@ H5
* @param p ?=<~^Lk
*/
JnY$fs*"
publicvoid setP(int p){ FQ`(b3.
if(p <= 0) p!_[qs
p = 1; !NTH.U:g
this.p = p; 2HD:JdL
} "Ht'{ &
XIKvH-0&
/** 3A_G=WaED
* 每页记录数量 \^jjK,OK
*/ =J](.78
publicint getNum(){ *r;xw
return num; Vz{>cSz#
} :5J_5,?;`
p}uncIod
/** pr_>b`p6
* if(num<1) num=1 28a$NP\KW
*/ sf$o(^P9\A
publicvoid setNum(int num){ #AShbl jm+
if(num < 1) R::zuv
num = 1; 'S*k_vuN
this.num = num; L_~8"I_
} (-,>qMQs
;r.EC}>m
/** Lkn4<'un
* 获得总页数 -jB3L:
*/ TkRmV6'w
publicint getPageNum(){ ziiwxx_
return(count - 1) / num + 1; 0Qnd6mb
} \9`#]#1bx5
-U>y
/** `<U5z$^QTw
* 获得本页的开始编号,为 (p-1)*num+1 ?F_)-
*/ H]&gW/=
publicint getStart(){ s3:9$.tiR[
return(p - 1) * num + 1; ;'0=T0\
} .1#kDM
iG#}`
/** E"6X|I n
* @return Returns the results. :Wc_Utt
*/ Qs%B'9")
publicList<E> getResults(){ :QPf~\w?
return results; .XS9,/S
} lq>AGw
Y1)!lTG
public void setResults(List<E> results){ nls
this.results = results; wP<07t[-g
} z=g$Exl
pvF-Y9Xb
public String toString(){ W3GNA""O
StringBuilder buff = new StringBuilder VL\t>n
q9]IIv
(); Ji?#.r`"n
buff.append("{"); wMWW=$h#\
buff.append("count:").append(count); d|lpec
buff.append(",p:").append(p); T.ML$"f
buff.append(",nump:").append(num); 5Sva}9H
buff.append(",results:").append 36vgX=}
cj$d=k~
(results); F9a^ED0l\
buff.append("}"); r^1+cwy/7P
return buff.toString(); 02=ls V!U
} r@kP*
~TqT}:,H
}
'V
(,.'
`\CVV*hP
M'L;N!1A