Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .;S1HOHz4
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bR1Q77<G\
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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 kZ]pV=\Y*
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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 jP0TyhM
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。 }$sTnea
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分页支持类: #3{{[i(;i
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java代码: W`P>vK@=
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package com.javaeye.common.util; Gd'_X D
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import java.util.List; 4@Z!?QzW
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publicclass PaginationSupport { ks
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publicfinalstaticint PAGESIZE = 30; V#+F*w?&D
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privateint pageSize = PAGESIZE; _3NH"o
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privateList items; yjq|8.L[
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privateint totalCount; D #7q3s
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privateint[] indexes = newint[0]; ]m7x&N2
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privateint startIndex = 0; ]=]MJ3_7
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public PaginationSupport(List items, int hy@b/Y![M
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totalCount){ s?&S<k-=fr
setPageSize(PAGESIZE); Xy`'h5
setTotalCount(totalCount); Y"^.6
setItems(items); ZR"qrCSw`
setStartIndex(0); fC[~X[H
} )O$S3ojZ
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public PaginationSupport(List items, int HD1/1?y!@q
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totalCount, int startIndex){ U.b|3E/^
setPageSize(PAGESIZE); (<@`MPI\@
setTotalCount(totalCount); i el@"E 4
setItems(items); rz2,42H]
setStartIndex(startIndex); jGo\_O<of
} qn,fx6v4
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public PaginationSupport(List items, int >6@,L+-6r
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totalCount, int pageSize, int startIndex){ DRTT3;,N
setPageSize(pageSize); TZ3gJ6 Cb
setTotalCount(totalCount); {*r!oD!'
setItems(items); GU 9p'E
setStartIndex(startIndex); .2_xTt
} m(EVC}Y
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publicList getItems(){ &p*rEs
return items; 84i0h$ZZo
} &.#dZ}J
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publicvoid setItems(List items){ 8Bh
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this.items = items; hd[t&?{=
} }odjaM}5Nc
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publicint getPageSize(){ 2+pXtP@O
return pageSize; w>}n1Nc$G
} ) ]<^*b>
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publicvoid setPageSize(int pageSize){ &OEBAtc/
this.pageSize = pageSize; {ot6ssT=D
} =<zlg~i
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publicint getTotalCount(){ E9t8SclV
return totalCount; "Vp:Sq9y
} [Ls%nz|
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publicvoid setTotalCount(int totalCount){ t("koA=.
if(totalCount > 0){ '?fGI3b~/
this.totalCount = totalCount; /11CC \
int count = totalCount / q|IU+r:! 3
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pageSize; Goy[P2m
if(totalCount % pageSize > 0) +^J;ic
count++; '"ze Im~
indexes = newint[count]; 5B8fz;l= B
for(int i = 0; i < count; i++){ jqTK7b
indexes = pageSize * lH@goh
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i; 8YgRJQZ!
} w{;~
}else{ |lu@rN
this.totalCount = 0; =}u?1~V
} i.eMrzJ|
} kGakdLl
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publicint[] getIndexes(){ i=pfjC
return indexes; </SO#g^r<
} kE!ky\E
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publicvoid setIndexes(int[] indexes){ $?VYHkX
this.indexes = indexes; qLKL*m
} QA)"3g
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publicint getStartIndex(){ "GJ.`Hj
return startIndex; D5].^*AbZ
} ~XvMiWuo
9y} J|z
publicvoid setStartIndex(int startIndex){ > %Hw008
if(totalCount <= 0) 1]A\@(
this.startIndex = 0; "d
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elseif(startIndex >= totalCount) >fkV65w{*
this.startIndex = indexes %zDi|WZ
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[indexes.length - 1]; s&wm^R
elseif(startIndex < 0) c|(Q[=
this.startIndex = 0; 1:./f|m
else{ wsc=6/#u
this.startIndex = indexes AUfcf*
[;'$y:L=g
[startIndex / pageSize]; !ZCxi
} bX5/xf$q
} h=n\c6Q
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publicint getNextIndex(){ o$7UWKW8
int nextIndex = getStartIndex() + *TCV}=V G
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pageSize; q6%m .X7
if(nextIndex >= totalCount) km`";gUp>
return getStartIndex(); Pi,86?
else ^%Ln@!P
return nextIndex; ~(`MP<
} x8wsx
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publicint getPreviousIndex(){ X76rme
int previousIndex = getStartIndex() - _6]CT0
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pageSize; ,ZO?D|M1
if(previousIndex < 0) XB:E<I'q!3
return0; }?O>.W,/
else [<Mls@?
return previousIndex; UF}Ji#fqn
} ygK,t*T20
Vyc
} qS
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抽象业务类 hVJ}EF0
java代码: d4A:XNKB
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/** ?f!&M
* Created on 2005-7-12 wARd^Iw
*/ Kv#Q$$)r
package com.javaeye.common.business; `nc=@" 1
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import java.io.Serializable; TIF =fQ
import java.util.List; Wi~?2-!
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import org.hibernate.Criteria; 1p<*11
import org.hibernate.HibernateException; li#ep?5h^
import org.hibernate.Session; gnf4H
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import org.hibernate.criterion.DetachedCriteria; 6J cXhlB`
import org.hibernate.criterion.Projections; wX!0KxR/Z
import SWT)M1O2
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org.springframework.orm.hibernate3.HibernateCallback; f>Tn#OW
import VmXXj6l&
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org.springframework.orm.hibernate3.support.HibernateDaoS BXytAz3
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upport; (ti E%nF+
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import com.javaeye.common.util.PaginationSupport; uE..1N&*
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public abstract class AbstractManager extends "od2i\
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HibernateDaoSupport { bY~V?yNgKM
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privateboolean cacheQueries = false; \"Qa)1|
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privateString queryCacheRegion; ~{{7y]3M-
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publicvoid setCacheQueries(boolean gTdr
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cacheQueries){ {Z>Mnw"R
this.cacheQueries = cacheQueries; 1>umf~%Wa
} {c<cSrfI
@jZ1WHS_a
publicvoid setQueryCacheRegion(String f'Oj01[
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queryCacheRegion){ <uo@k'
this.queryCacheRegion = /8 "rCh|m-
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queryCacheRegion; VLfKN)g
} <EY{goW
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publicvoid save(finalObject entity){ @z=L\e{
getHibernateTemplate().save(entity); @S&QxE^
} &WS'Me
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publicvoid persist(finalObject entity){ Q+O./1x*,
getHibernateTemplate().save(entity); J2$,'(!(
} 4lwoTGVZj
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publicvoid update(finalObject entity){ iUZV-jl2/
getHibernateTemplate().update(entity); =i},$"Bf*%
} &QFc)QP{
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publicvoid delete(finalObject entity){ e^N}(Kpy
getHibernateTemplate().delete(entity); iAt&927
} p ^)3p5w
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publicObject load(finalClass entity, 9vCCE[9
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finalSerializable id){ 1=PTiDMJ<*
return getHibernateTemplate().load tCv}+7)
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(entity, id); )`mBvS.}
} )kYDN_W
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publicObject get(finalClass entity, vz&88jt
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finalSerializable id){ q RRvZhf
return getHibernateTemplate().get r$Oa
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(entity, id); AP ]`'C
} P#[?Kfi
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publicList findAll(finalClass entity){ |w5,%#AeO$
return getHibernateTemplate().find("from Q!r` G
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" + entity.getName()); jVqpokWH
} COHook(:
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publicList findByNamedQuery(finalString /.>%IcK
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namedQuery){ LG??Q+`l
return getHibernateTemplate 1jpft3*x
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().findByNamedQuery(namedQuery); ?.Ip(g
} %l!-rXp
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publicList findByNamedQuery(finalString query, }hcY5E-n
"/%o'Fq
finalObject parameter){ 2WE01D9O
return getHibernateTemplate 1*.*\4xo
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IT(v
().findByNamedQuery(query, parameter); Lb{.}
} *&hbfsP:
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publicList findByNamedQuery(finalString query, TIK'A<
}T}xVd0
finalObject[] parameters){ !lBK!'0
return getHibernateTemplate 7}`FXB
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().findByNamedQuery(query, parameters); ex66GJQe1
} xqQK-?k
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publicList find(finalString query){ Mh{>#Gs
return getHibernateTemplate().find Eqh*"hE7
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(query); ;d
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} tq51;L
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publicList find(finalString query, finalObject nYe:$t3F=
9Q'[>P=1
parameter){ p1W6 s0L
return getHibernateTemplate().find R`B} T<*
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(query, parameter); gEw9<Y
} 0E)M6
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public PaginationSupport findPageByCriteria ,H1K sN
}F|B'[wn
(final DetachedCriteria detachedCriteria){ hE<Sm*HU
return findPageByCriteria 9SJSUv:@
7k00lKA\w
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7
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} h\Q@zR*0a
W Bb*2
public PaginationSupport findPageByCriteria WdB\n/BWB
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(final DetachedCriteria detachedCriteria, finalint JpxQS~VX
>]o>iOz;]
startIndex){ ]wi0qc2{
return findPageByCriteria 4Z5;y[k(
5"X@<;H%
(detachedCriteria, PaginationSupport.PAGESIZE, %0Qq~J@Lu
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startIndex); %?Q&a ]
} ^AiQNL}
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public PaginationSupport findPageByCriteria >0uj\5h)I]
{s@ 0<!
(final DetachedCriteria detachedCriteria, finalint 5:C>:pA V
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pageSize, `5rfO6;
finalint startIndex){ [HL>Lp&A?
return(PaginationSupport) xW2?\em
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getHibernateTemplate().execute(new HibernateCallback(){ sZ;Gb^{Z
publicObject doInHibernate XVJH>Zw
X(\L1N
(Session session)throws HibernateException { e
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Criteria criteria = 7_jlNr7uk
pMAP/..+2
detachedCriteria.getExecutableCriteria(session); /Z,hQ>/
int totalCount = *aFY+.;U`
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((Integer) criteria.setProjection(Projections.rowCount pM}~/
7B\Q5fLQ
()).uniqueResult()).intValue(); $15H_X*!
criteria.setProjection cOZBl;}
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(null); !IA\c(c^
List items = .!Kqcz% A
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criteria.setFirstResult(startIndex).setMaxResults j%Xa8$
"a3?m)
(pageSize).list(); /Ov1eQBNG
PaginationSupport ps = R/kJUl6HEl
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new PaginationSupport(items, totalCount, pageSize, WtaOf_
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startIndex); E.+%b;Eqe
return ps; 9NNXj^7
} i5&,Bpfo-
}, true); WuFBt=%
} TdT`Vf
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public List findAllByCriteria(final w7&.Uqjf
WglpWp)
DetachedCriteria detachedCriteria){ &%;n9K
return(List) getHibernateTemplate M)nh~gU
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().execute(new HibernateCallback(){ e9tb]sAG
publicObject doInHibernate u6Wan*I?
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(Session session)throws HibernateException { DEt!/a{X
Criteria criteria = z[myf]@
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detachedCriteria.getExecutableCriteria(session); d3S Me
return criteria.list(); .\&k]}0qA?
} 3HW&\:q5'M
}, true); {?2|rv)
} 'W>y v
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public int getCountByCriteria(final }L&LtW{X
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DetachedCriteria detachedCriteria){ ^SKHYo`,,N
Integer count = (Integer) )rt%.`
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getHibernateTemplate().execute(new HibernateCallback(){ Jj5VBI!Ok
publicObject doInHibernate
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{
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(Session session)throws HibernateException { <VutwtA
Criteria criteria = s{8=Q0^
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detachedCriteria.getExecutableCriteria(session); BV
}CmU&DA
return f}p`<z
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criteria.setProjection(Projections.rowCount RqP_^tB
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()).uniqueResult(); B]:|;d
} G6}&k[d5%
}, true); RA[%8Rh)
return count.intValue(); `b] wyP
} u[Si=)`VPk
} au/LoO#6Ro
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用户在web层构造查询条件detachedCriteria,和可选的 x[Hx.G}5+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _ DT,iF*6
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PaginationSupport的实例ps。 W5= j&&|!
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ps.getItems()得到已分页好的结果集 .{*l,
ps.getIndexes()得到分页索引的数组 M\
ps.getTotalCount()得到总结果数 -!\%##r7~
ps.getStartIndex()当前分页索引 P=KhR&gwV~
ps.getNextIndex()下一页索引 x<Gjr}
ps.getPreviousIndex()上一页索引 *78c2`)[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;<B
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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 VHMQY*lk
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一下代码重构了。 1[u{y{9 q
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我把原本我的做法也提供出来供大家讨论吧: H!u8+
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首先,为了实现分页查询,我封装了一个Page类: Mj6,VD9L
java代码: (a8iCci:
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/*Created on 2005-4-14*/ REE.8_
package org.flyware.util.page; !ehjLFS? _
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/** 2IRARZ,3
* @author Joa ?[m1?
* AWx@Z7\z"g
*/ k{{3nenAG
publicclass Page { KV|D]}
*fIn<Cc
/** imply if the page has previous page */ 6w;`A9G[YI
privateboolean hasPrePage; zow8 Q6f
V|kN 1
A
/** imply if the page has next page */ &]RE 5!
privateboolean hasNextPage; ")\V
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/** the number of every page */ zGyRzxFN
privateint everyPage; C$~ly=@
1Q!^*D
/** the total page number */ 2EZ7Vdz2
privateint totalPage; n7K%lj-.P
Q\
6-SAS
/** the number of current page */ ncOgSj7e
privateint currentPage; l&U$LN$*e
8b~
/** the begin index of the records by the current ^uN[rHZ*u
a{Y|`*7y
query */ 3en67l
privateint beginIndex; l5Ko9CG
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/** The default constructor */ gj
@9(dk%
public Page(){ cnQ2/ZZp~
3~Fag1Hp
} .Y]0gi8z
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/** construct the page by everyPage =<p=?16
x
* @param everyPage BO7HJF)a
* */ P(b[|QF
public Page(int everyPage){ 0RMW>v/7kL
this.everyPage = everyPage; FGHCHSqLq
} 2&n6:"u|
f7\X3v2W}3
/** The whole constructor */ O!f37n-TB
public Page(boolean hasPrePage, boolean hasNextPage, 4c 8{AZ
l1'v`!
k)*apc\W
int everyPage, int totalPage, 4s9@4
int currentPage, int beginIndex){ so$(-4(E O
this.hasPrePage = hasPrePage; {R(CGrI
this.hasNextPage = hasNextPage; Gt*K:KT=L
this.everyPage = everyPage; >| ,`E
this.totalPage = totalPage; _v 0iH
this.currentPage = currentPage; E] /2u3p
this.beginIndex = beginIndex; .x,y[/[[)
} OzrIiahz/
u%z'.#r; a
/** #2ta8m),
* @return MooH`2Fd
* Returns the beginIndex.
6A]I" E]5
*/ 6P717[
publicint getBeginIndex(){ DMG'8\5C
return beginIndex; !(? 7V
} )AkBo
&T0]tzk*,
/** 6wWhM&Wd
* @param beginIndex YlbX_h2S"
* The beginIndex to set. 9GCK3
*/ xcWR#z{z
publicvoid setBeginIndex(int beginIndex){ lqmQQ*Z
this.beginIndex = beginIndex; 2{~`q
} $ MH;v_'a
r[}nr H&8
/** / kK*%TP
* @return /tj]^QspS
* Returns the currentPage. ]goJ- &
*/ a<\n$E#q
publicint getCurrentPage(){ Y0|){&PCt
return currentPage; iY07lvG<
} Qw2-Vv4!"
jGz~}&B
/** l9Ol|Cb&
* @param currentPage n8; p]{
* The currentPage to set. EG`AkWy
*/ cb]X27uww
publicvoid setCurrentPage(int currentPage){
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this.currentPage = currentPage; g_c@Kyf
} sYDav)L.
c:0n/DC
/** *izCXfW7
* @return Xzg >/w
8J
* Returns the everyPage. vkhPE(f
*/ PaQ lQ#
publicint getEveryPage(){ !nkIXgWz
return everyPage; e_Hpai<b
} !`?i>k?Q E
i'H]N8,A
/** 5Z; 5?\g
* @param everyPage j]kgdAq>
* The everyPage to set. 0*5Jq#5
*/ "o`?-bQ:
publicvoid setEveryPage(int everyPage){ iQ:eR]7X
this.everyPage = everyPage; %?].(
Lc
} L%Zr3Ct
K)>F03=uE
/** K<5yjG8&
* @return X/:V{2
* Returns the hasNextPage. v LN KX;9
*/ rD <T
publicboolean getHasNextPage(){ H%Vf$1/TF
return hasNextPage; vA_,TS#Bo
} i4i9EvWp
U&])ow):
/** !;&\n3-W
* @param hasNextPage PVlCj
* The hasNextPage to set. o5&b'WUJ=
*/ :
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publicvoid setHasNextPage(boolean hasNextPage){ .tG3g:
this.hasNextPage = hasNextPage; +`Q]p "G
} "Tser*i )
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/** >v@3]a
i
* @return 1T|")D
* Returns the hasPrePage. `B3-#!2X
*/ Izu____
publicboolean getHasPrePage(){ GNv{Ij<
return hasPrePage; Cscu
} %8u9:Cl):
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/** {f`Y\_r$@
* @param hasPrePage }WFI/W'
* The hasPrePage to set. hzM;{g>t
*/ ";7N$hWE
publicvoid setHasPrePage(boolean hasPrePage){ P=,\wM6T|
this.hasPrePage = hasPrePage; %!A:Ka!m.
} t27UlFX
2c[HA
/** *s 4Ym
* @return Returns the totalPage. s(Gs?6}>T
* AYY(<b
*/ yW'{Z]09
publicint getTotalPage(){ [Lje?M* r
return totalPage; "1Hn?4nz5
} lG0CCOdQ
PZ6R+n8
/** Q`8-|(ngw
* @param totalPage 98u@X:3
* The totalPage to set. ${z#{c1
*/ MMKN^a"GA
publicvoid setTotalPage(int totalPage){ V1M|p!
this.totalPage = totalPage; `=hCS0F
} !c)F;
9F3,
} x1g-@{8]j
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s) s9Z,HY
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ~
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个PageUtil,负责对Page对象进行构造: {'+{ASpO!
java代码: `+< ^Svou
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:F"IOPfU5[
/*Created on 2005-4-14*/ <& PU%^Ha
package org.flyware.util.page; sS{Co8EJn
^wZx=kas
import org.apache.commons.logging.Log; TC<Rg?&yb
import org.apache.commons.logging.LogFactory; 2Cy,#X%j>
z@e(y@
/** s'N <
* @author Joa [!;sp~
* @Hp%4$=
*/ x[TLlV:{
publicclass PageUtil { 6;Z`9PGp
d:>^]5cE&
privatestaticfinal Log logger = LogFactory.getLog U5j4iz'
FYFlh^}
(PageUtil.class); >%`SXB&9
N}nE9z5
/** y7h^_D+Ce
* Use the origin page to create a new page _/Ve~(
"
* @param page BJ3<"D{.*4
* @param totalRecords O,
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* @return #]1jvB
*/ |)>+&
xk
publicstatic Page createPage(Page page, int UmpHae
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totalRecords){ .9ZK@xM&?
return createPage(page.getEveryPage(), 'vtJl
7=yM40
page.getCurrentPage(), totalRecords); T&/n.-@nk
} cz/E
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/** $LuU
* the basic page utils not including exception xPm{'J+b~
}XUI1H]jk
handler ?;UR9f|!
* @param everyPage QhRz57'
* @param currentPage gzhIOeY
* @param totalRecords cZYvP
* @return page *%jtcno=Y
*/ '")'h
publicstatic Page createPage(int everyPage, int `"ks0@^U
%k?/pRv$>
currentPage, int totalRecords){ Q'=7#_
everyPage = getEveryPage(everyPage); gp$]0~[tO
currentPage = getCurrentPage(currentPage); 0OG
3#pE
int beginIndex = getBeginIndex(everyPage, )skpf%g
_oa*E2VN
currentPage); a.UYBRP/l
int totalPage = getTotalPage(everyPage, Pm^FSw"
9 9:.j=
totalRecords); aJ=)5%$6kc
boolean hasNextPage = hasNextPage(currentPage, q0ab]g+
cyd&bxPgj+
totalPage); C=Fu1Hpb
boolean hasPrePage = hasPrePage(currentPage); .,'4&}N}
_VgFuU$h
returnnew Page(hasPrePage, hasNextPage, o@PvA1
everyPage, totalPage, Or$"f3gq
currentPage, ?1r;6
QPp31o.!5
beginIndex); ~eP~c"L
} JP"#9f
~~&Bp_9QXN
privatestaticint getEveryPage(int everyPage){ I_Lm[
return everyPage == 0 ? 10 : everyPage; X7K{P_5l
} I8@leT\9M
'-f` 5 X
privatestaticint getCurrentPage(int currentPage){ _&gO>G,uy
return currentPage == 0 ? 1 : currentPage; wpN [0^M-0
} zobFUFx
5G'2 Wby'#
privatestaticint getBeginIndex(int everyPage, int 3TjyKB *!
dzbbFvG
currentPage){ :8bq0iqsV
return(currentPage - 1) * everyPage; \>"Zn7
} X xwcvE
c CZ$TH
privatestaticint getTotalPage(int everyPage, int gIRZ kT`
4@F8-V3q4
totalRecords){ ]==7P;_-
int totalPage = 0; K~-V([tWg
2 7dS.6
if(totalRecords % everyPage == 0) v;z8g^L
totalPage = totalRecords / everyPage; (aJ$1bT=T
else :rufnmsP<U
totalPage = totalRecords / everyPage + 1 ; 0wqw5KC
rVOF
return totalPage; )xg8#M=K
} m7A3i<6p
\N|}V.r
privatestaticboolean hasPrePage(int currentPage){ hB>FJZQ_
return currentPage == 1 ? false : true; e 5(|9*t
} )~$ejS
@HI@PZ>
privatestaticboolean hasNextPage(int currentPage, &uaSp,L
l(3PxbT
int totalPage){ VFq\{@-
%
return currentPage == totalPage || totalPage == K0'p*[yO/j
@$p6w
0 ? false : true; c?c"|.-<p
} 7?_gm>]a
k&K'FaM!
{<Y!'WL{
} r4 5}o
!p36OEx
XH!n{Of
d{WOO)j
$mq+/|bn
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。 MfI+o<{r
.VmRk9Z
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 J1M9),
9}K
K]m6u}
做法如下: h3\(660>$
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 p@DVy2,EY
y^X]q[-?
的信息,和一个结果集List: 8c%N+E]
java代码: j{tr''yN
A2PeI"y
d[;&2Jz*
/*Created on 2005-6-13*/ C^]UK
package com.adt.bo; PK{FQ3b2{
) P+<=8@a
import java.util.List; #MMp0
1!+0]_8K
import org.flyware.util.page.Page; 3$_- 0>
#w^Ot*{!N
/** *r~6R
* @author Joa "Rf|o6!d
*/ -4J.YF>
publicclass Result { a9 S&n5
TEK#AR
private Page page; //$^~}wt
w17{2']
private List content; "yU<X\ni
)iPU
/** U~zy;MT
* The default constructor CX{M@x3m
*/ t08[3Q&
public Result(){ aiw4J
super(); @@!]Raj=
}
{pRa%DF
0+_;6
/** 9(a*0H
* The constructor using fields F
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* PUd/|Rc/}
* @param page u
VUrg;>
* @param content 0o.h{BN
*/ v,3}YDu
public Result(Page page, List content){ oO;<$wx2t
this.page = page; p Bu}c<
this.content = content; s2+_`Ogg
} -HFyNk]>
fB4zqMSfE
/** _Mh..#)`[
* @return Returns the content. =k!F`H`/%'
*/ 2:[G4
publicList getContent(){ Sc]h^B^7
return content; @Js@\)P79
} S.C7%XU
Yka>r9wr
/** iNn?G C>
* @return Returns the page. J,`I>^G
*/ 4J[csU
public Page getPage(){ Pn}oSCo
return page; Qeq=4Nq
} RHt~:D3*
BJZGQrsz
/** gX5.u9%C\
* @param content [s-!tE3-
* The content to set. 1Zp^X:(
*/ H Mfhe[A?
public void setContent(List content){ ^g+M=jq _
this.content = content; E3_ 5~>
} ~~,#<g[
n4AQ
/** ugW.nf*O
* @param page <ou=f'
* The page to set. j6rwlwN
*/ 3"6-X_
publicvoid setPage(Page page){ R
<u\
-
this.page = page; Xpmi(~n
} OZl0I#@A
} !8J%%Ux&M
yMb.~A^$J
8U-<Q>
8{Wh4~|+
niCq`!
2. 编写业务逻辑接口,并实现它(UserManager, sQ82(N7l
=XUt?5
UserManagerImpl) myZ8LQ&
java代码: z-kB!~r
!wjD6NK
8qq'q"g
/*Created on 2005-7-15*/ GYri\ <[
package com.adt.service; xC$CRzAe5p
HD}3mP
import net.sf.hibernate.HibernateException; cvnRd.&
f87lm*wZ
import org.flyware.util.page.Page; s|Zv>Qt
$Mqw)X&q
import com.adt.bo.Result; Y&*nj`n
`H|#l\
/** [PU0!W;
* @author Joa 'A#l$pJp7
*/ |+Ub3<b[]
publicinterface UserManager { EnjSio0
</h}2x
public Result listUser(Page page)throws |H-zm&h>'
t=r*/DxX=
HibernateException; >Co5_sCe
;e^`r;]
} &28%~&L
^@xn 3zJ
<o_(,,P%
:#spL*FIx
4kf8Am(
java代码: \&X*-T[]j
E#+|.0*!s
f!##R-A
/*Created on 2005-7-15*/ 8>V)SAI'
package com.adt.service.impl; _WHGd&u
g h&,U`
import java.util.List; :+}Eo9
Ha20g/UN.
import net.sf.hibernate.HibernateException; Q>>II|~;J
g=n /w
import org.flyware.util.page.Page; #vvQ1ub
import org.flyware.util.page.PageUtil; !qVnziE,,
8 gzf$Oc
import com.adt.bo.Result; p EbyQ[
import com.adt.dao.UserDAO; S9S%7pE
import com.adt.exception.ObjectNotFoundException; xy1R_*.F^T
import com.adt.service.UserManager; y[sO0u\
%C(^v)"
/** si3@R?WR6*
* @author Joa =G%L:m*
*/ XVkCYh4,
publicclass UserManagerImpl implements UserManager { Kh2!c+Mw
);5H<[
private UserDAO userDAO; '#@tovr
qFYM2
/** ju?D=n@i
* @param userDAO The userDAO to set. G^/8lIj
*/ rnTjw
"%
publicvoid setUserDAO(UserDAO userDAO){ $y+Bril5W
this.userDAO = userDAO; ~5b^Gvb?
} Eh&HN-&
H)l7:a
/* (non-Javadoc) I Z{DR
* @see com.adt.service.UserManager#listUser l^E)XWd
c0u1L@tj
(org.flyware.util.page.Page) "AUHe6Yv
*/ .=<<b|
public Result listUser(Page page)throws $fl+l5?9
a EmLf
HibernateException, ObjectNotFoundException { ,fW%Qv
int totalRecords = userDAO.getUserCount(); C{8(ew
if(totalRecords == 0) z1 P=P%F
throw new ObjectNotFoundException rRzc"W}K+
OtFGo8
("userNotExist"); &i?>mt
page = PageUtil.createPage(page, totalRecords); zsuXN *
List users = userDAO.getUserByPage(page); K/ 5U;oC
returnnew Result(page, users); 1=Nh<FuQ
} ct![eWsuB
~zT7 43
} R\d)kcy4
sW]fPa(cn,
aJ^RY5
]KE"|}B
B(h%>mT[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 TdWatvY5p
Y]6kA5
询,接下来编写UserDAO的代码: `PApmS~}
.
3. UserDAO 和 UserDAOImpl: Vmf!0-
java代码: ]ovb!X_
Kk9W=vd
p?XVO#
/*Created on 2005-7-15*/ (N
:vDq'
package com.adt.dao; c}r"O8M
;o-c.-!F
import java.util.List; T1_>qnSz
M=Cl|
import org.flyware.util.page.Page; =/SBZLR(9
!{%BfZX<&
import net.sf.hibernate.HibernateException; dNfME*"yN
>s|zrS)
/** X/' t1
* @author Joa w=feXA3-S
*/ /@QPJ~%8Ud
publicinterface UserDAO extends BaseDAO { @pkQ2OM
2
K@>($BX]
publicList getUserByName(String name)throws HS
>B\Ip"
N>Q~WXvV#
HibernateException; *\PCMl
S@Q4fmH
publicint getUserCount()throws HibernateException; #)PAvBJ;m
>JckN4v
publicList getUserByPage(Page page)throws {~cM 6W]f
:ExCGS[
HibernateException; NY3.?@Z
"1HKD
} qe<aJn
^M6R l0
I )wc&>Lc
BH\!yxK
_-5| "oJ
java代码: ]CxDm
zSo(+ D
&[
U~1)a(Yu;
/*Created on 2005-7-15*/ )
o`ep{<t
package com.adt.dao.impl; P}8cSX9
^ZPynduR
import java.util.List; 1'4?}0Dok
^bk:g}o
import org.flyware.util.page.Page; {j[a'Gb
JBk >|q"
import net.sf.hibernate.HibernateException; ^aR^M\38
import net.sf.hibernate.Query; 8 @A}.:
wU(!fw\
import com.adt.dao.UserDAO; b>]k=zd
^ DCBL&I
/** x|`BF%e/v
* @author Joa t0.71(
*/ _Nacqa
public class UserDAOImpl extends BaseDAOHibernateImpl )0?u_Z]w9
-]<<}@NF
implements UserDAO { 7&&3@96<*#
h,|. qfUk
/* (non-Javadoc) >["X(%&w
* @see com.adt.dao.UserDAO#getUserByName *b8AN3!
K( r@JW
(java.lang.String) *3\ Nj6
*/ vR4omB{
publicList getUserByName(String name)throws 7!/!a*zg
e?_uJh"
HibernateException { !xvAy3
String querySentence = "FROM user in class zmhL[1qj
zS*vKyye>
com.adt.po.User WHERE user.name=:name"; #Q` TH<
Query query = getSession().createQuery +vt?3i\^.
oLIgj,k{*
(querySentence); Zk~~`h
query.setParameter("name", name); 3HqTVq`&
return query.list(); pv8vW'G\E
} 8_/,`}9
@Nn'G{8OG
/* (non-Javadoc) %>-?oor
* @see com.adt.dao.UserDAO#getUserCount() =z zmz7op
*/ EGVS8YP>h
publicint getUserCount()throws HibernateException { LK+67Y{25
int count = 0; @{{6Nd5
String querySentence = "SELECT count(*) FROM >S>B tRl
tUi@'%>=5
user in class com.adt.po.User"; XaF;IS@A
Query query = getSession().createQuery ^cCNQS}r
S$ n?
(querySentence); m:6*4_!
count = ((Integer)query.iterate().next \+j:d9?
),J6:O&
()).intValue(); `Wd4d2aLG
return count; '*D>/hn|:]
} |j=Pj)5J
S!66t?vHB
/* (non-Javadoc) EV@yJ]
* @see com.adt.dao.UserDAO#getUserByPage I,W`s
dkg|
kw'
(org.flyware.util.page.Page) CsEU:v
*/ A|YiSwyy
publicList getUserByPage(Page page)throws _*ar\A`
XhUVDmeUMb
HibernateException { XtqhK"f%
String querySentence = "FROM user in class ,\T7{=ZG\!
F^.~37=@
com.adt.po.User"; k)9+;bKQQ
Query query = getSession().createQuery 3
$a;
7%Ou6P$^fr
(querySentence); ?x/Lb*a^
query.setFirstResult(page.getBeginIndex()) Va[t'%~&zR
.setMaxResults(page.getEveryPage()); liMw(F2
return query.list(); N}nE?|N=5
} o)n=n!A
0#CmB4!<O
} WO6R04+WV
qM<CBcON
m48Ab`
{YG qa$+\
p'A43
至此,一个完整的分页程序完成。前台的只需要调用 wLzV#8>
VTwQD"oB
userManager.listUser(page)即可得到一个Page对象和结果集对象 !j%uwje\
tz5\O}
的综合体,而传入的参数page对象则可以由前台传入,如果用 |K" nSXzk
0BH-kr
webwork,甚至可以直接在配置文件中指定。 +8Y|kC{9"
g7{:F\S
下面给出一个webwork调用示例: qh+&Z x~
java代码: EQ.K+d*K][
Tp|>(~;ai
Y]7 6y>|e
/*Created on 2005-6-17*/ J9MAnYd)i
package com.adt.action.user; Ym.{
{^=
=;(L$:l~
import java.util.List; ~E/=nv$
3m$ck$
import org.apache.commons.logging.Log; axOEL:-|Bu
import org.apache.commons.logging.LogFactory; Ww"]3
import org.flyware.util.page.Page; )2Bb,p<Wr
H>o \C
import com.adt.bo.Result; [=",R&uD$
import com.adt.service.UserService; `Tei
import com.opensymphony.xwork.Action; eV~"T2!Sb
%CrTO(
/** P EMBh?)g
* @author Joa |AT`(71
*/ ~nb(e$?N
publicclass ListUser implementsAction{ =sAU5Ag68
'Yi="kno
privatestaticfinal Log logger = LogFactory.getLog qzEv!?)a
&;~?\>?I
(ListUser.class); x4(8
=&Z
t fD7!N{
private UserService userService; 2j#Dwa(lZQ
U#&+n-npO
private Page page; OL%}C*Zq
4H NaE{O4
privateList users; B]vR=F}*
*;xGH
/* kBxEp/y
* (non-Javadoc) W 1u!&:O
* v*&jA8D
* @see com.opensymphony.xwork.Action#execute() Y`#6MhFT7
*/ pmOUl 8y4
publicString execute()throwsException{ wa~zb!y<
Result result = userService.listUser(page); /]U;7)
page = result.getPage(); (G/(w%#7_
users = result.getContent(); R>]7l!3^1
return SUCCESS; z~==7:Os
} tfu`_6
!
,{zDMA
/** S^;;\0#NK
* @return Returns the page. ~$C}?y^ a
*/ !Z
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public Page getPage(){ k DXQpe
return page; ^d@2Y0hH
} tRO=k34
Zw _aeJ
/** 5423Ky<
* @return Returns the users. tTF<DD}8
*/ <h;_:
publicList getUsers(){ @56*r@4:q
return users; 6yO5{._M
} ~( 0bqt3c
u{h67N
/** 5gII|8>rQ
* @param page <QO1Yg7}
* The page to set. 0kNKt(_
*/ DA04llX~
publicvoid setPage(Page page){ 5!cp^[rGL
this.page = page; O!^ >YvOh
} KeRC8mYp
/]_|uN)Q
/** j"hEs(t
* @param users &3;"$P
* The users to set.
D~BL Txq
*/ /-i m
g^^
publicvoid setUsers(List users){ )QRT/, ;c
this.users = users; |Olz h63k:
} `/'p1?Z"
1G.?Y3DC<
/** ^1vKhO+p$
* @param userService UP$>,05z6
* The userService to set. l2:-).7xt
*/ 3;VH'hh_
publicvoid setUserService(UserService userService){ 3 o$zT9j
this.userService = userService; +RJKJ:W
} WJu(,zM?G
} >j3':>\U
7}y@VO6]
6wj o:I
u$C\#y7
]1XtV<
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, |m6rF7Q
]s\vc:cc?
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 c61OT@dZEA
`/`iLso&-
么只需要: aL*MC gb'
java代码: [Eccj`\e g
ep?D;g
U._fb=
<?xml version="1.0"?> W] DGt|JP
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ygH )U.
:"Otsb7
1.0//EN" "http://www.opensymphony.com/xwork/xwork- F'OO{nF
o $W@@aM
1.0.dtd"> cTzR<Yr
?upd
<xwork> t-o,iaPG3
}$ySZa9
<package name="user" extends="webwork- .r{t&HO;Y
M2p|&Z%
interceptors"> 8<mloM-4
YY :{/0?
<!-- The default interceptor stack name yn$1nt4
7)5G 1
--> _h5d~
<default-interceptor-ref w8R7Ksn(
gd]S;<Jh
name="myDefaultWebStack"/> HcJ!(
)W>$_QxbN
<action name="listUser" T#i;=NP"
x {Utf$|
class="com.adt.action.user.ListUser"> nOd;Zw
<param XHj%U
O8b#'f~
name="page.everyPage">10</param> cW_wIy\]&
<result i%.k{MY
[?|yQ x
name="success">/user/user_list.jsp</result> vs[!B-
</action> D
(8Z90
`^[Tu 1
</package> {<@ud0A:\
@s
cn ?t
</xwork> l0`bseN<
$Wj{B@k
_AX,}9
3N-
'{c6]U
_s#]WyU1g
8y<.yfgG
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 2t_g\Q
"{qnm+G
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 "qF/7`e[
\%Y`>x.
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 NQ;X|$!zH
97\K ]Tr
p7-\a1P3
k(^TXUK\o
)1B?<4
我写的一个用于分页的类,用了泛型了,hoho }q]*aADe
qpjZ-[UC
java代码: %q3`k#?<
b way+lh
X>yDj]*4P
package com.intokr.util; ZCj1Cz]"l<
035jU '
import java.util.List; He'VqUw_
XXn3K BIf
/** M0xhcU_
* 用于分页的类<br> }:c~5whN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> BXU0f%"8U
* {g1"{
* @version 0.01 /huh}&NNu
* @author cheng hvO$ f.i
*/ (>A#|N1U
public class Paginator<E> { '}(>s%~
privateint count = 0; // 总记录数 "GZ}+K*GG
privateint p = 1; // 页编号 ~Yg)8
privateint num = 20; // 每页的记录数 !9NF@e'&!
privateList<E> results = null; // 结果 L-E?1qhP>
R|8L'H+1x
/** `.O$RwC&7B
* 结果总数 s<# BxN
*/ %i3[x.M
publicint getCount(){ 4[x`\
return count; %La7);SeY
} 9y&;6V.'
?+7~E8
publicvoid setCount(int count){ YYFS
({
this.count = count; WO9vOS>
} N".BC|r
@d~]3T
/** 2;>uP#1]
* 本结果所在的页码,从1开始 h%u!UHA
* +JC"@
* @return Returns the pageNo. ~D}fy
*/ C}<e3BXc
publicint getP(){ .hxFFk%5
return p; v&;JVai
} BC_<1
c
R\3v=PR[
/** qS! Lt3+
* if(p<=0) p=1 ~=c5q
* ~ L%,9
* @param p /v<Gt%3X
*/ (n.IK/:
publicvoid setP(int p){ 4Ol1T(J#
if(p <= 0) Hs8JJGXWB
p = 1; $rk=#;6]v;
this.p = p; !ck~4~J
} D:j5/ *
+{=U!}3|
/** $eT[`r
* 每页记录数量 qvo!nr7
*/ HxW/t7Z(
publicint getNum(){ l
lcq~*zz
return num;
+ug2p;<B
} k=kkF"
/*fx`0mY)
/** G)NqIur*Z
* if(num<1) num=1 nM&