Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 \H
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ["]r=l
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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 T#&tf^;
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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 L<8:1/d\
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分页支持类: `yiw<9yp2
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java代码: X'BFR]cm
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package com.javaeye.common.util; ! n@*6
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import java.util.List; NFDh!HUm
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publicclass PaginationSupport { +OGa}9j-
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publicfinalstaticint PAGESIZE = 30; V)HX+D>
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privateint pageSize = PAGESIZE; qHM,#W<
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privateList items; ?f}lYQzM
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privateint totalCount; h%2;B;p]
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privateint[] indexes = newint[0]; lt:xN?--A?
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privateint startIndex = 0; 7bC1!x*qw
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public PaginationSupport(List items, int j%7N\Vb
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totalCount){ _tl
setPageSize(PAGESIZE); p_ H;|m9
setTotalCount(totalCount); *OoM[wEY
setItems(items); 4<P=wK=a8X
setStartIndex(0); pi/Jto25z
} EL--?<g
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public PaginationSupport(List items, int ;"d>lyL
y,D@[*~Xb
totalCount, int startIndex){ 5"5tY
setPageSize(PAGESIZE); 2h_XfY'3pX
setTotalCount(totalCount); pQ:7%+Om
setItems(items); 6a_MA*XK
setStartIndex(startIndex); LIm{Y`XU
} ]6:|-x:m
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public PaginationSupport(List items, int )sONfn
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totalCount, int pageSize, int startIndex){ blUnAu
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setPageSize(pageSize); %MA o<,ha
setTotalCount(totalCount); *wvd[q h
setItems(items); FR bmeq3c
setStartIndex(startIndex); E.ugr])
} 6"OwrJB
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publicList getItems(){ D'Fj"&LK
return items; xZMQ+OW2i
} v--Qbu
s *8)|N
publicvoid setItems(List items){ %a'Nf/9=:
this.items = items; SC Qr/Q
} vZ&{
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publicint getPageSize(){ QsO%m
return pageSize; x/<eY<Vgm?
} >ocDh~@aP
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publicvoid setPageSize(int pageSize){ WLO4P
this.pageSize = pageSize; bjR:5@"
} .=kXO{>
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publicint getTotalCount(){ oJ:\8>)9
return totalCount; XCN^>ToD
} L
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publicvoid setTotalCount(int totalCount){ y;GwMi$KI
if(totalCount > 0){ uV|%idC
this.totalCount = totalCount; [iO*t,3@h
int count = totalCount / &E/0jxM1
7NFRCCXHQ
pageSize; 1ZrJ7a7=
if(totalCount % pageSize > 0) K6z)&<
count++; (#)-IdXXO<
indexes = newint[count]; q{c/TRp7
for(int i = 0; i < count; i++){ !gyEw1Re7
indexes = pageSize * crDm2oA~t
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} .='hYe.
}else{ +YX*.dW
this.totalCount = 0; b}-/~l-:
} &{R]v/{p]
} x%`.L6rj
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publicint[] getIndexes(){ 1y{@fg~..
return indexes; Qt~QJJN?oF
} J Yesk
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publicvoid setIndexes(int[] indexes){ Z/*X)mBuB
this.indexes = indexes; b\.l!v n0
} NDo>"in
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publicint getStartIndex(){ {[[j .)
return startIndex; g,O3\jjQ
} *[ww;
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publicvoid setStartIndex(int startIndex){ vw'BKi
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if(totalCount <= 0) xE"QX
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this.startIndex = 0; @&F\ M}
elseif(startIndex >= totalCount) G,-x+e"
this.startIndex = indexes Be4n\c.
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[indexes.length - 1]; hlO,mU
elseif(startIndex < 0) 8j^3_lD
this.startIndex = 0; 9C"d7--
else{ 9bb5?b/
this.startIndex = indexes Gc0/*8u/
Y )](jU%o
[startIndex / pageSize]; %AV[vr,
} s6HfN'
} Eq82?+9
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publicint getNextIndex(){ e"u89acp
int nextIndex = getStartIndex() + [+_0y[~,tB
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pageSize; W>2m%q
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if(nextIndex >= totalCount) c%O8h
return getStartIndex(); bKb}VP
else r)/nx@x
return nextIndex; tEC`->|
} 1^R:[L4R`
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publicint getPreviousIndex(){ C0#"U f
int previousIndex = getStartIndex() - a?gziCmS?C
/2jw]ekQ'
pageSize; meM61ue_2
if(previousIndex < 0) .`5BgX7W
return0; bPhb d
else :,*{,^2q:
return previousIndex; n+94./Mh
} !-<PV
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} $ri'tJ+
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抽象业务类 r-]Hm Y x
java代码: %J?"ZSh
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/** }3xZ`vX[T
* Created on 2005-7-12 C?h`i ^ >2
*/ 0//B+.#
package com.javaeye.common.business; ,^d!K(xb
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import java.io.Serializable; cPL]WI0(
import java.util.List; !5escR!\D
RbA.%~jjx*
import org.hibernate.Criteria; 1-6[KBQ8
import org.hibernate.HibernateException; ),#hBB`ZA
import org.hibernate.Session; tMQz'3,X
import org.hibernate.criterion.DetachedCriteria; &8^ch,+pD
import org.hibernate.criterion.Projections; hJIF!eoI
import #Emz9qTsce
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org.springframework.orm.hibernate3.HibernateCallback; wEp*j+Mmce
import (}:n#|,{M
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org.springframework.orm.hibernate3.support.HibernateDaoS F')fi0=
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upport; `x'vF#
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import com.javaeye.common.util.PaginationSupport; |4tnG&=
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public abstract class AbstractManager extends e_{!8u.+
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HibernateDaoSupport { w6w'Jx
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privateboolean cacheQueries = false; V`;$Ua;y
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privateString queryCacheRegion; -jJw wOm
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publicvoid setCacheQueries(boolean IC:wof "
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cacheQueries){ YKZk/m&H
this.cacheQueries = cacheQueries; n$S`NNO{]
}
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publicvoid setQueryCacheRegion(String EDkxRfY2/
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queryCacheRegion){ /e0cx:.w
this.queryCacheRegion = G',*"mZQ[
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queryCacheRegion; AvNU\$B4aG
} H^e0fm
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publicvoid save(finalObject entity){ 0D*uZ,oBEw
getHibernateTemplate().save(entity); .;'3Roi
} ra'h\m
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publicvoid persist(finalObject entity){ .M$}.v
getHibernateTemplate().save(entity); k'd(H5A
} x`#|8
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publicvoid update(finalObject entity){ ?<#2raH-
getHibernateTemplate().update(entity); >nnjLrI
} {MaFv
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publicvoid delete(finalObject entity){ i{$h]D_fD
getHibernateTemplate().delete(entity); kK]^q|vb6
} Jf,)Y>EI
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publicObject load(finalClass entity, {Va"o~io
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finalSerializable id){ f~3_Rv!
return getHibernateTemplate().load DjX*2O
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(entity, id); &!kr&g#]
} N~%F/`Z<+
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publicObject get(finalClass entity, MR/8
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finalSerializable id){ Pkm3&sW
return getHibernateTemplate().get AV0C9a/td
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(entity, id); :!wdqn
} Ikkv <uY
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publicList findAll(finalClass entity){ J)w58/`?t
return getHibernateTemplate().find("from WaVP+Ap
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" + entity.getName()); {ER%r'(4Z
} -'tgr6=|w"
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publicList findByNamedQuery(finalString l"\W] 'T:r
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namedQuery){ 6[h3pb/m
return getHibernateTemplate s^/<6kwO
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().findByNamedQuery(namedQuery); 9M)N2+hkZ
} :(,Eq?
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publicList findByNamedQuery(finalString query, WH.5vrY Z
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finalObject parameter){ T5eXcI0t
return getHibernateTemplate %}U-g"I
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().findByNamedQuery(query, parameter); QES[/i +
} EV:y}
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publicList findByNamedQuery(finalString query, 2EubMG
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finalObject[] parameters){ |M?yCo
return getHibernateTemplate <y(uu(c
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().findByNamedQuery(query, parameters); eZ]4,,m
} lO-: [@
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publicList find(finalString query){ `}s$cgEG
return getHibernateTemplate().find Azrc+ k
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(query); 0u4:=Z}W
} 6g*B=d(j
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publicList find(finalString query, finalObject 8v6YOG"b
q
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parameter){ m8F-#?~
return getHibernateTemplate().find /@5X0m
Aw)='&;^z
(query, parameter); ]3_oT^$:
} S~+}_$
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public PaginationSupport findPageByCriteria T`{W$4XS
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(final DetachedCriteria detachedCriteria){ OLc/Vij;
return findPageByCriteria .~0A*a
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 1(`>9t02/?
} -I.OvzQ*
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public PaginationSupport findPageByCriteria T<\Q4Coth
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(final DetachedCriteria detachedCriteria, finalint }O<u
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startIndex){ !o2lB^e8
return findPageByCriteria "Y9
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f)\ =LV
(detachedCriteria, PaginationSupport.PAGESIZE, RYDV60*O6
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startIndex); &[}T41
} k#TonT
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public PaginationSupport findPageByCriteria [k(oQykq
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(final DetachedCriteria detachedCriteria, finalint -.:[a3c?
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pageSize, +2=N#LM
finalint startIndex){ 0[g8
return(PaginationSupport) k/W$)b:Of`
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getHibernateTemplate().execute(new HibernateCallback(){ /"+n{*9
publicObject doInHibernate 5An|#^]
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(Session session)throws HibernateException { K'~wlO@O
Criteria criteria = GcQO&oq|
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detachedCriteria.getExecutableCriteria(session); ?fDF Rms
int totalCount = I~EQuQ >=
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((Integer) criteria.setProjection(Projections.rowCount pPm[<^\# S
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()).uniqueResult()).intValue(); ,9gyHQ~
criteria.setProjection /u{ 9UR[g
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(null); %iY-}uhO
List items = XX",&cp02V
"BZ6G`
criteria.setFirstResult(startIndex).setMaxResults #q40 >)]
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(pageSize).list(); S/& _
PaginationSupport ps = =YkJS%)M)
2>0[^ .;"
new PaginationSupport(items, totalCount, pageSize, KHKf+^u u
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startIndex); mV0F^5
return ps; Oz!#);v
} :;\>jxA
}, true); AxLnF(eG
} 7yxZe4~|#
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public List findAllByCriteria(final ~M`QFF
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DetachedCriteria detachedCriteria){ s2L|J[Y"s
return(List) getHibernateTemplate 8;/`uB:zV
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().execute(new HibernateCallback(){ $w`QQ^\
publicObject doInHibernate W+V#z8K
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(Session session)throws HibernateException { O{rgx~lLJt
Criteria criteria = y-O#
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*`[dC,+`.
detachedCriteria.getExecutableCriteria(session); )vO;=%GQ
return criteria.list(); SC)4u l%
} >K**SjVG
}, true); Lzu;"#pw
} aQ mgDF
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public int getCountByCriteria(final I
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DetachedCriteria detachedCriteria){ q3Re
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Integer count = (Integer) gBz$RfyF
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getHibernateTemplate().execute(new HibernateCallback(){ rXXIpQRi$S
publicObject doInHibernate 3UgusH3
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(Session session)throws HibernateException { 5f2ah4 g
Criteria criteria = J"'2zg1&
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detachedCriteria.getExecutableCriteria(session); 5"xZ'M~=
return L8n1p5gx3
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criteria.setProjection(Projections.rowCount ;%P$q9*C
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()).uniqueResult(); 'gd3 w~
} eSf
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}, true); iaBy/!i
return count.intValue(); r1&b#r>
} 0mo^I==J1
} jV)!9+H#
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用户在web层构造查询条件detachedCriteria,和可选的 T677d.zaT
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )iadu
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PaginationSupport的实例ps。 qp
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ps.getItems()得到已分页好的结果集 <Ur(< WTV
ps.getIndexes()得到分页索引的数组 g/,fjM_
ps.getTotalCount()得到总结果数 [tDUR
ps.getStartIndex()当前分页索引 ?z0f5<dL
ps.getNextIndex()下一页索引 a6=mE?JTB
ps.getPreviousIndex()上一页索引 1L1_x'tT%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]$(::'pmK
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 L(Q v78F
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一下代码重构了。 wm0vqY+N$
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我把原本我的做法也提供出来供大家讨论吧: 8[5%l7's
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首先,为了实现分页查询,我封装了一个Page类: Gxfw!aF~
java代码: p3O%|)yV
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/*Created on 2005-4-14*/ ^zkTV_,cRp
package org.flyware.util.page; Yu=4j9e_mG
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/** Qfo'w%px
* @author Joa vFY/o,b \
* hABC
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*/ (WiA
publicclass Page { 6u/3"A]'
^T"9ZBkb
/** imply if the page has previous page */ I2("p.+R
privateboolean hasPrePage; yAtM|:qq
)xCpQ=nS
/** imply if the page has next page */ lqAU5K{wQ
privateboolean hasNextPage; _v4TyJ
==(9P`\
/** the number of every page */ 5)V]qV$
privateint everyPage; gVCkj!{
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/** the total page number */ $1oU^VY
privateint totalPage; a{Y:hrd:Z
S]ZO*+
/** the number of current page */ >=^g%K$L6J
privateint currentPage; YD2M<.U
\*6%o0c
/** the begin index of the records by the current (xK=/()}q
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query */ KL*ZPKG
privateint beginIndex; Tz58@VY V
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/** The default constructor */ }aXc,;Ps
public Page(){ s2g}IZfo
FB@c
+*1
} l#%Y]1*
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/** construct the page by everyPage jD0^,aiG
* @param everyPage *j><a
* */ h0Acpd2
public Page(int everyPage){ g]iWD;61
this.everyPage = everyPage; KQ?E]}rZ
} IvetQ+
kP%'{
/** The whole constructor */ :<gmgI
public Page(boolean hasPrePage, boolean hasNextPage, `kyr\+hp
!40{1U&@a`
ujB:G0'r
int everyPage, int totalPage, 0@,,YZf
int currentPage, int beginIndex){ G9 z Q{E
this.hasPrePage = hasPrePage; Y[$[0
this.hasNextPage = hasNextPage; wED~^[]f
this.everyPage = everyPage; C5i]n? )S
this.totalPage = totalPage; !OPK?7
this.currentPage = currentPage; v;el= D
this.beginIndex = beginIndex; s?=f,I
} vkE6e6,Qc
6;dB
/** T'\lntN
* @return gO<>L0,j
* Returns the beginIndex. $b\Gl=YX^
*/ h_?D%b~5
publicint getBeginIndex(){ KmEm
return beginIndex; vBj{bnl
} V. 'EP
PPDm*,T.
/** (8@._
* @param beginIndex +q)
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* The beginIndex to set. @]WN|K
*/ ..'^1IOA
publicvoid setBeginIndex(int beginIndex){ n0@e%=H)I
this.beginIndex = beginIndex; $>OWGueq64
} t=iy40_T
Sq-mH=rs]
/** 76}
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* @return Nk86Y2h
* Returns the currentPage. l *yml
*/ cQu1WgQ
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publicint getCurrentPage(){ pHni"iT
return currentPage; `DC)U1
} F_zs"ex/
GasIOPzK
/** -2K`:}\y&
* @param currentPage 'RTz*CSZ
* The currentPage to set. KxGK`'E'r
*/ ss236&
publicvoid setCurrentPage(int currentPage){ ;wp)E nF
this.currentPage = currentPage; 4ZQXYwfC|
} wB?;3lTS
!R[o6V5T
/** OY51~#BF
* @return lk%rE
* Returns the everyPage. -1:yqF.x
*/ .?[2,4F;
publicint getEveryPage(){ +<"sC+2
return everyPage; %S]5wR6;_
} (VWTYG7
n$axqvG
/** hoO8s#0ED
* @param everyPage PC7U&*x@
* The everyPage to set. g(,gg1mG
*/ gK9@-e
publicvoid setEveryPage(int everyPage){ g.s~Ph- G
this.everyPage = everyPage; ]{0
2!
} X@\rg}kP
)C<c{mjk(
/** oZmni9*SD
* @return {&4+W=0
n
* Returns the hasNextPage. -SlLX\>p
*/ ^ bexXYh
publicboolean getHasNextPage(){ k,0JW=Vh>|
return hasNextPage; mPi4.p)
} bfQ+}|;
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/** #:v|/2
* @param hasNextPage y7u"a)T
* The hasNextPage to set. K!).QB'
*/ "/S-+Ufn
publicvoid setHasNextPage(boolean hasNextPage){ :;#^h]Q
this.hasNextPage = hasNextPage; dArg'Dc4
} TXv3@/>ZlG
NJI-8qTGI
/** cD YKvrPY
* @return $GSn#} yz
* Returns the hasPrePage. ^{DXin 1O`
*/ Ev,>_1#Xm
publicboolean getHasPrePage(){ :tl*>d~
return hasPrePage; :3gtc/p t>
} f0~<qT?:n
~dkS-6q~Q
/** f1rP+l-C<
* @param hasPrePage ,ZHIXylZ
* The hasPrePage to set. 0>6J -
*/
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publicvoid setHasPrePage(boolean hasPrePage){ %d c=QSL
this.hasPrePage = hasPrePage; u3a"[DB9c
} @>}!g9c
bE74Ui
/** Bk_23ygO_
* @return Returns the totalPage. ~Y7>P$G)
* C*a>B,H
*/ )[C]1N=tK
publicint getTotalPage(){ =2F;'T\6
return totalPage; J/mLmSx
} 7?9QlUO
bBk_2lg=4)
/** s!:'3[7+
* @param totalPage pZ,=iqr
* The totalPage to set. n`8BE9h^
*/ 2F%2K?$`Ej
publicvoid setTotalPage(int totalPage){ _ I"}3*
this.totalPage = totalPage; 1YV ;pEw3w
} Z@2^> eC
RZoSP(6
} wW
EnAW~
mM0VUSy
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io%WV%1_
mhVdsa
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 NOM6},rp
aO)Cq5
个PageUtil,负责对Page对象进行构造: (yA`h@@WS
java代码: U2<8U
f@yInIzRJ
vX1 8
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/*Created on 2005-4-14*/ OIJNOu I
package org.flyware.util.page; "'U+T:S
e}>3<Dh
import org.apache.commons.logging.Log; %])U (
import org.apache.commons.logging.LogFactory; \ GYrPf$
dyWj+N5(
/** iOY: a
* @author Joa o|`[X'
* U/}YpLgdD
*/ O{^8dwg
publicclass PageUtil { K Q^CiX
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privatestaticfinal Log logger = LogFactory.getLog jKr\mb
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(PageUtil.class); R&.mNji*
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/** ES,T[
* Use the origin page to create a new page &A}hx\_T
* @param page HOt,G
_{
* @param totalRecords Op()`x
m
* @return FQTAkkA_!
*/ Mh"X9-Ot
publicstatic Page createPage(Page page, int -.xiq0
iq^F?$gFk
totalRecords){ moS0y?N
return createPage(page.getEveryPage(), 0:I[;Qt
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}Kfae
page.getCurrentPage(), totalRecords); \uPyvA=
} S5o,\wT
|PtfG2Ty?
/** 8+i=u"<
* the basic page utils not including exception HK
NT. a
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handler ,I6li7V
* @param everyPage <*Nd%Ca
* @param currentPage fn#qcZv?
* @param totalRecords t)|~8xpP
* @return page mq}V @H5
*/ s
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publicstatic Page createPage(int everyPage, int 71n3d~!O>
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currentPage, int totalRecords){ RDfvD|}VN
everyPage = getEveryPage(everyPage); A!cY!aQ
currentPage = getCurrentPage(currentPage); ?lE&ow
int beginIndex = getBeginIndex(everyPage, j(A>M_f;
a[Nm<
qV05
currentPage); iGPrWe@.
int totalPage = getTotalPage(everyPage, e@Mg9VwDc
vBzUuX
totalRecords); jB<B_"
boolean hasNextPage = hasNextPage(currentPage, ZIN1y;dJ
'ZJb`
totalPage); D V\7KKJE
boolean hasPrePage = hasPrePage(currentPage); $Qz<:?D
-Ew>3Q
returnnew Page(hasPrePage, hasNextPage, Z`_x|cU?J
everyPage, totalPage, zLgc j(;
currentPage, %QG3~b%
h
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beginIndex); NH;e|8
} _@i-?Q
Wv|CJN;4
privatestaticint getEveryPage(int everyPage){ 4E2#krE%
return everyPage == 0 ? 10 : everyPage; 7t+d+sQ-l
} K@<*m!%<2
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privatestaticint getCurrentPage(int currentPage){ | }L=e.
return currentPage == 0 ? 1 : currentPage; p>,D F9W`
} -oUGmV_
x <a}*8"
privatestaticint getBeginIndex(int everyPage, int el U %Z9
Ni8%K6]z
currentPage){ vh.-9eD
return(currentPage - 1) * everyPage; fF(AvMsO
} O1UArD
B`.aQ
privatestaticint getTotalPage(int everyPage, int L pq)TE#
pV(k6h
totalRecords){ #1%ahPhR+
int totalPage = 0; je@&|9h
=@
acg0
if(totalRecords % everyPage == 0) K\wu9z8M
totalPage = totalRecords / everyPage; 8o[gzW:Q)U
else 0Ix,c( %
totalPage = totalRecords / everyPage + 1 ; }]H7uC!t
hP8w3gl_
return totalPage; 3b\s;!
} r&Nh>6<&/
BdMd\1eMw
privatestaticboolean hasPrePage(int currentPage){ 2Y%7.YX"
return currentPage == 1 ? false : true; sZ~03QvkT
} }-sh
xe^M2$clb\
privatestaticboolean hasNextPage(int currentPage, |{(JUXo6K
iZ>P>x\
int totalPage){ ^SsdM#E
return currentPage == totalPage || totalPage == vmEn$`&2t
K\KQ(N8F
0 ? false : true; CVvl &on
} A9N8Hav
~"0{<mMcX
l?$X.CwX
} ]]_5_)"4
w>\oz
x${C[gxq9F
+,,dsL
RhKDQGdd
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 eI:x4K,#
50dN~(;p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 J~xm[^0
PYC
做法如下: r>! @Z2%s
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 lz6CK
ViyG%Sm
的信息,和一个结果集List: c~/poFj
java代码: wEl7mg !
:R=7dH~r
v(R^LqE
/*Created on 2005-6-13*/ "=+i~N#Sc
package com.adt.bo; 4OLYB9HP_
*g
%bdO
import java.util.List; TghT{h@
v FQ]>nX
import org.flyware.util.page.Page; O-ENFA~E;v
)MSCyPp5
/** {`k&Q +gY
* @author Joa 7[0Mr,^
*/ ^t71${w##
publicclass Result { x^_c4,i)
|A,.mOT
private Page page; 3N!v"2!#
.b`8
+
private List content; Cq7 uy
h?;03>6A&]
/** qc.TYp
* The default constructor )g?jHm-p\
*/ BMQ4i&kF|
public Result(){ UroC8Tm
super(); tS\Db'C7
} qhG2j;
_a9oHg
/** vol (%wB
* The constructor using fields YahW%mv`d
* b?cO+PY01
* @param page
LjEMs\P\
* @param content 6C<GYzzo
*/ ,Xn%0]
public Result(Page page, List content){ rx;;|eb,
this.page = page; Q(Q?L5
this.content = content; \(=xc2
} DWx;cP8[
<h+@;/v:
/** /E{tNd^S
* @return Returns the content. 4Ozcs'}
*/ Isvb;VT9L
publicList getContent(){ yn@wce
return content; R=48:XG3/K
} wpC.!T
=_3rc\0
/** ?-o_]!*v0/
* @return Returns the page. lb*;Z7fx<'
*/ @].!}tz
public Page getPage(){ ^?\|2H
return page; AY"wEyNU
} Sfc,F8$&N
i4WHjeo\
/** B<Cg_C
* @param content B]b/(Q+
* The content to set. 1^GRUbOU[
*/ 2!CL8hG5:
public void setContent(List content){ S=`$w
this.content = content; r~7}w4U
} ~Al3Dv9x
(d,OLng
/** _\,lv
\u
* @param page _akjgwu
* The page to set. |%#NA!e4wA
*/ 4s'%BM-r-
publicvoid setPage(Page page){ G;pmR^
this.page = page; .!lLj1?p
} /CKn XU;
} T*C
F5S
cH:&S=>h
xX{Zh;M&[
`m#G'E I
eLgq
)
2. 编写业务逻辑接口,并实现它(UserManager, *<[\|L:#]Z
=b1
y*?
UserManagerImpl) `)KGajB
java代码: ?|}qT05
(n2_HePE
" ;T
a8
/*Created on 2005-7-15*/ :9x]5;ma
package com.adt.service; 7Lj:m.0O^
SdMLO6-
import net.sf.hibernate.HibernateException; M$>Nd6,@N
L*4=b
(3
import org.flyware.util.page.Page; *A}td8(
''! j:49
import com.adt.bo.Result; 7(C)vtEO:
saQo]6#
/** QGGBI Ku
* @author Joa eAjR(\f>
*/ <pKOFN%m
publicinterface UserManager { ]-a/)8
T/%Y_.NtU
public Result listUser(Page page)throws Nr)DU.f
%Q.M& U
HibernateException; "A~D(1K
E&Lml?@
} {9j0k`A
$rbr&TJ
Ky8,HdAq
RX^8`}N
^ u0y<kItX
java代码: ?
IlT[yMw
OS>%pgv
rTJqw@]#WH
/*Created on 2005-7-15*/ At[SkG}b
package com.adt.service.impl; i*&b@.7N
n<b}6L}
import java.util.List; Qn-nO_JL
Y<N#{)Q
import net.sf.hibernate.HibernateException; G@T_o4t
m@L>6;*
import org.flyware.util.page.Page; :iQJ9Hdz
import org.flyware.util.page.PageUtil; HB.:/5\
A%&lW9z7
import com.adt.bo.Result; Y[rCF=ZVH
import com.adt.dao.UserDAO; Y(T$k9%}+
import com.adt.exception.ObjectNotFoundException; +~
Y.m8
import com.adt.service.UserManager; !g|[A7<|
mOyNl
-f
/** W%9~'pXgB
* @author Joa 20Jlf?
*/ {D,-
Whi
publicclass UserManagerImpl implements UserManager { 8LuU2Lo
N?A}WW#
private UserDAO userDAO; +I:/8,&-x
:Z83*SPc
/** KO[Ty'
* @param userDAO The userDAO to set. )WvOa] :
*/ bpDlFa
publicvoid setUserDAO(UserDAO userDAO){ 1n.F`%YG
this.userDAO = userDAO; Vy=+G~
} `:0Auw9h
4T){z^"
/* (non-Javadoc) CSNz8
y
* @see com.adt.service.UserManager#listUser (&_~eYZU
QV#HN"F/K
(org.flyware.util.page.Page) 9El{>&Fs4
*/ UZ:z|a3
public Result listUser(Page page)throws (8N E'd8
#B_H/9f(
HibernateException, ObjectNotFoundException { %qVD-Jln
int totalRecords = userDAO.getUserCount(); yio8BcXH54
if(totalRecords == 0) &$~irI
throw new ObjectNotFoundException 5+(Cp3
!rZZ/M"i
("userNotExist"); A9GSeW<
page = PageUtil.createPage(page, totalRecords); @FRas00)|
List users = userDAO.getUserByPage(page); TeJ=QpGW2
returnnew Result(page, users); xxC2 h3
} "837b/>/
*A0d0M]cg
} |h.@Xy
C +Wa(K
6_;n bqY&
$L'[_J
sM9utR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fK^;?4
wS|hc+1
询,接下来编写UserDAO的代码: fUq
#mkq}
3. UserDAO 和 UserDAOImpl: )3 '8T>^<K
java代码: p$Floubh]
{!1RlW
j:HIcCp
/*Created on 2005-7-15*/ Fc^!="H
package com.adt.dao; wf^p?=Ke
8 9maN
import java.util.List; ( De>k8
r( bA>L*mk
import org.flyware.util.page.Page; K}Q:L(SSr\
jK{qw
import net.sf.hibernate.HibernateException; -6e^`c6{
;O<-4$
/** 8RcLs1n/
* @author Joa sy(.p^Z
*/ (7"CYAe:;
publicinterface UserDAO extends BaseDAO { .OlPVMFt
ofs'xs1C
publicList getUserByName(String name)throws NE|Q0g
NLt"yD3t
HibernateException; E<@N4%K_Q
"EZpTy}Ee
publicint getUserCount()throws HibernateException; sDBwD%sb
5eM{>qr}
publicList getUserByPage(Page page)throws ^W~8)Rbf
!L2!:_
HibernateException; x-b}S1@
UUGX@
} 5+qdn|9%T
ffsF], _J
60WlC0Y~u
^AoX|R[1%
equi26jhr
java代码: 4hkyq>c}
>1` '5A}s
|*l^<= =
/*Created on 2005-7-15*/ $h5QLN
package com.adt.dao.impl; |fo#pwX
*aGJ$ P0
import java.util.List; Ny2bMj.o
7vc4 JO]
import org.flyware.util.page.Page; Qm_;o(
Zu94dFP
import net.sf.hibernate.HibernateException; }[(v(1j='~
import net.sf.hibernate.Query; zT93Sb
Q(4~r+
import com.adt.dao.UserDAO; C 1)+^{7ef
_v++NyZXx
/** >'jkL5l
* @author Joa ;jBS:k?
*/ -C* 6>$A
public class UserDAOImpl extends BaseDAOHibernateImpl ~(:0&w%e
:m>Vp
implements UserDAO { #c~-8=
{Q@?CT
/* (non-Javadoc) cg9*+]rc
* @see com.adt.dao.UserDAO#getUserByName >;%LW}
%
b*4aUpW
(java.lang.String) Iz>\qC}
*/ 9Q\RCl_1
publicList getUserByName(String name)throws 4M+f#b1
?8;WP&
HibernateException { *^CN2tm
String querySentence = "FROM user in class (0rcLNk{|
We'= /!
com.adt.po.User WHERE user.name=:name"; s4 Vju/
Query query = getSession().createQuery :)FNhx3
Mhc5<~?
(querySentence); bfkFk
query.setParameter("name", name); K??jV&Xor
return query.list(); d@zxgn7o
} &%eM
vFeR)Ox's
/* (non-Javadoc) S"`{ JCW$
* @see com.adt.dao.UserDAO#getUserCount() 5r dt
*/ ngk:q5Tp
publicint getUserCount()throws HibernateException { f"^t~q[VS
int count = 0; ++ObsWZ
String querySentence = "SELECT count(*) FROM ce719n$
"W_E!FP]r
user in class com.adt.po.User"; uLNOhgSUf
Query query = getSession().createQuery %=V"
}P[
fd62m]X
(querySentence); ,'sDauFn
count = ((Integer)query.iterate().next `>RM:!m6=$
Ec }9R3 m
()).intValue(); }r"E\~E
return count; S&;)F|-q
} -^8OjGat
Lmw)Ts>
/* (non-Javadoc) 6F%6]n
* @see com.adt.dao.UserDAO#getUserByPage % 3fpIzm
^9YS dFH/
(org.flyware.util.page.Page) !~j9Oc^
*/ >4HB~9dKU
publicList getUserByPage(Page page)throws :R3&R CTZ
nFro#qx
HibernateException { -x?|[ +%
String querySentence = "FROM user in class W>'gG}.
.mOm@<Xdg
com.adt.po.User"; PE[5oH
Query query = getSession().createQuery D hk$e
B =DV!oUg
(querySentence); {yi!vw
query.setFirstResult(page.getBeginIndex()) PAVlZ}kj
.setMaxResults(page.getEveryPage()); 8-smL^~%#
return query.list(); rERtOgi
} e"Z,!Q^-L
=YtK@+| i
} FE#|5;q.
U<'$ \P
NVDIuh
P# ;pQC
x26 sH5
至此,一个完整的分页程序完成。前台的只需要调用 Yt r*"-
.&K?@T4l
userManager.listUser(page)即可得到一个Page对象和结果集对象 JBISA _Y
ADMeOdgca
的综合体,而传入的参数page对象则可以由前台传入,如果用 'n?"f |G
dE(d'*+a
webwork,甚至可以直接在配置文件中指定。 !'>#!S~h3
U:$`M,762Z
下面给出一个webwork调用示例: l8lJ &
java代码: LD ,T$"
#O'g*]j
#EH\Q%
/*Created on 2005-6-17*/ T$V8n_;
package com.adt.action.user; 0BOL0<Wq
2[KHmdgtB
import java.util.List; lI5>d(6p
5)w;0{X!P
import org.apache.commons.logging.Log; Mv7tK
l
import org.apache.commons.logging.LogFactory; zEeix,IU
import org.flyware.util.page.Page; ldG$hk'
oK&G
import com.adt.bo.Result; GVdJ&d\x
import com.adt.service.UserService; e"2x!(&n(
import com.opensymphony.xwork.Action; wJ7Fnj>u%
4 @9cO)m
/** #|Je%t}~
* @author Joa F+V[`w*k
*/ @$wfE\_L
publicclass ListUser implementsAction{ ]oC7{OoX
#;'*W$Wk2
privatestaticfinal Log logger = LogFactory.getLog mQtOx
h0VeXUM;.
(ListUser.class); g;y*F;0@
iyMoLZ5
private UserService userService; o1Wf#Zq
r;fcBepO
private Page page; e#?rK=C?9
@t8{pb;v
privateList users; L!2Ef4,wAz
VO*fC
/* mpl^LF[
* (non-Javadoc) c* )PS`]t
* ~hU^5R-%
* @see com.opensymphony.xwork.Action#execute() {d,^tG}
*/ x}N1Wl=8g
publicString execute()throwsException{ l{_1`rC'
Result result = userService.listUser(page); By0Zz
page = result.getPage(); sAPYQ
users = result.getContent(); IPnx5#eB
return SUCCESS; Uql7s:!,U
} SwhArvS
rVnolA*%
/** 6^nxw>-
* @return Returns the page. `mKK1x
*/ <U""CAE
public Page getPage(){ }h\]0'S~J~
return page; Oxh.&
} qTnk>g_oS&
Pv3 e*I((
/** Hp3T2|uL
* @return Returns the users. ==~
lc;
*/ Y;q['h
publicList getUsers(){ z%L\EP;o}
return users; h)yAge
} \H.1I=<
xA"7a
/** n)>nfnh
* @param page %ZZW
p%uf
* The page to set. ZDl(q~4?z
*/ JA^Y:@<{/
publicvoid setPage(Page page){ v
iM6q<Ht
this.page = page; C)0JcM
} 1V 2"sE
FtxmCIVIV~
/** gA:N>w&<X
* @param users k&\ 6SK/
* The users to set. 4 O~zkg
*/ 'B$qq[l]S
publicvoid setUsers(List users){ 4krK CD>|G
this.users = users; RU GhhK
} x-ShY&k
C<\O;-nHH
/** (8OaXif
* @param userService \^rAH@
* The userService to set. iKuSk~
*/ MzO4Yv"A
publicvoid setUserService(UserService userService){ Dz>v;%$S-
this.userService = userService; 4F>?G{ci
} R} aHo0r
} Q[N6# C:(4
&B5@\Hd;
w6[uM%fHG
QC*>
qo
Wo+'j $k
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, :If1zB)
Gdf*x<T1
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 d*xKq"+
&E
s'|^ 6/
么只需要: Lz'05j3!
java代码: 5>'1[e45
-h<Rby
vo_m$ /O
<?xml version="1.0"?> i-4pdK u
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2_]"9d4
?`%)3gx|
1.0//EN" "http://www.opensymphony.com/xwork/xwork- P}+-))J
"##Ylq( "
1.0.dtd"> sA u ;i
;8
D31OT
<xwork> ?lYi![.o
0 oFRcU
<package name="user" extends="webwork- UlN+
GX+o A]
interceptors"> ?Rj)x%fN
jJF(*D
<!-- The default interceptor stack name /~Q2SrYH
dfBTx6/F
--> p Rn vd|
<default-interceptor-ref v]tbs)x;h
E}V8+f54S
name="myDefaultWebStack"/> a0oM KGW:
N!}r(Dd*
<action name="listUser" jc|"wN]
G#&R/Tc5N
class="com.adt.action.user.ListUser"> *LbRLwt
<param ]$'w8<D>t,
p}j$p'D.RI
name="page.everyPage">10</param> j`Xe0U<
<result n
4:Yc@,
OE(Z)|LF
name="success">/user/user_list.jsp</result> %z&=A%'a
</action> :6 ?&L
P%v7(bqL4+
</package> u:Q_XXT5
p2;-*D
</xwork> zice0({iJ
LO,G2]
tc%?{W\
_N 5$>2
$:R"IqDG
^h
z4IZ^
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 lZ5 lmsCU
Br2ZloJ@+
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6e6~82t8/
V/Q~NXN
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 YPraf$
X0Q};,
D=U"L-rRs
;Zb+WGyj
Hf
]aA_:
我写的一个用于分页的类,用了泛型了,hoho A`|OPi)
6>! ;g'k
java代码: Y4Hi<JWo
9 |Cu2
J;pn5k~3
package com.intokr.util; J+3PUfg>@R
V#:`:-$$+
import java.util.List; w{J0K;L
s7?Q[vN
/** s)dN.'5/
* 用于分页的类<br> >y%*HC!G
* 可以用于传递查询的结果也可以用于传送查询的参数<br> /xmUu0H$R
* ^zPa^lo-
* @version 0.01 3+gp_7L
* @author cheng ?Xscc mN
*/ \8%64ZL`
public class Paginator<E> { }R#YO$J7
privateint count = 0; // 总记录数 1s4+a^&
privateint p = 1; // 页编号 {FO>^~>l
privateint num = 20; // 每页的记录数 -EV_=a8[y
privateList<E> results = null; // 结果 XkZ82w#b
: [o0Va2 d
/** Zvd^<SP<?
* 结果总数 ob=GB71j55
*/ d5gYJ/Qv
publicint getCount(){ P+!j[X^
return count; Fj<#*2{]B
} &?\ h[3
lYkm1
publicvoid setCount(int count){ (J(JB}[X,
this.count = count; uc@f# (-
} ~C6Qp`VF
gz6BfHQG
/** \(Uw.ri
* 本结果所在的页码,从1开始 n5i#GvO^
* ,6Ulj+l
* @return Returns the pageNo. #gbJ$1s
*/ 0\f3L a
publicint getP(){ Zf~Em'g"3
return p; ]r;-Lx{F
} tZR%s
Nq|b$S [4
/** $ qk2!
* if(p<=0) p=1 d4h1#MK
* #% PnZ
/
* @param p mF\r]ovVm
*/ `!<RP'
publicvoid setP(int p){ ?5d7J,"<h
if(p <= 0) 6XPf0Gl
p = 1; X_Vj&{
this.p = p; yD|He*$S
} ~Aul 7[IH
c`
^I% i
/** j}NGyS" =
* 每页记录数量 {?c`0C
*/ ]F[ V6`H
publicint getNum(){ A7!!kR":
return num; uY+N163i
} ydFZ$W_}w
|V#h
"s
/** t>[K:[0U
* if(num<1) num=1 KF&1Y>t=
*/ T\\Q!pY
publicvoid setNum(int num){ hawE2k0p(
if(num < 1) (orO=gST-/
num = 1; ~D1.opj3
this.num = num; L7i^?40
} u`Kjs}F'
_bp9UJ
/** o'S&YD
* 获得总页数 NYbeIfL
*/ .s7Cr0^k,|
publicint getPageNum(){ r9@4-U7v&
return(count - 1) / num + 1; ki`7S
} ?rqU&my S
-'
7I|r
/** ooa>~!91P
* 获得本页的开始编号,为 (p-1)*num+1 mup<%@7m
*/ NbyVBl0=
publicint getStart(){ Zr`pOUk!4
return(p - 1) * num + 1; >*v!2=
} kqJ\kd
e-vwve
/**
)L}6to
* @return Returns the results. ]AjDe]
*/ bL>J0LWQ
publicList<E> getResults(){ rap`[O|l=
return results; f"emH
} ^F@z+q
k`H#u, &