Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qt}M&=}8Q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 bg Ux&3
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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 3q73L<f
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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 DURWE,W>
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分页支持类: AY5iTbL1
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java代码: ai-s9r'MI?
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package com.javaeye.common.util; rhc+tR
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import java.util.List; u0L-xC$L
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publicclass PaginationSupport { ^($'l)I
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publicfinalstaticint PAGESIZE = 30; G{!er:Vwdh
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privateint pageSize = PAGESIZE; O?X[&t
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privateList items; _nqnO8^IG4
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privateint totalCount; ULAr!
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privateint[] indexes = newint[0]; 5(H%Ia
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privateint startIndex = 0; ?:wb#k)Z/
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public PaginationSupport(List items, int g$s;;V/8e
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totalCount){ O#U maNj/
setPageSize(PAGESIZE); ."+lij=56
setTotalCount(totalCount); 8)0]cX
setItems(items); 0:v!'
setStartIndex(0);
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} rk8pL[|
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public PaginationSupport(List items, int | @AXW
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totalCount, int startIndex){ V^,gpTyv*
setPageSize(PAGESIZE); X8*g#lO?
setTotalCount(totalCount); mU-2s%X<.^
setItems(items); w5 . ^meU
setStartIndex(startIndex); G[mqLI{q
} /Q3>w -h
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public PaginationSupport(List items, int |4mvB2r
=#u4^%i)
totalCount, int pageSize, int startIndex){ _uO$=4Sd
setPageSize(pageSize); ,m<YSMKX
setTotalCount(totalCount); 9InP2u\&:
setItems(items); *Y(59J2
setStartIndex(startIndex); Y ]([K.I=
} +fk*c[FG
7z$Z=cs
publicList getItems(){ 2{h2]F
return items; Hi09?AX
} QH-CZ6M
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publicvoid setItems(List items){ 2?~nA2+vm
this.items = items; $YX{gk>
} :C_/K(Rkl
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publicint getPageSize(){ i%9vZ
return pageSize; m ~&
} <'4Wne.z!
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publicvoid setPageSize(int pageSize){ kD#n/RBgf
this.pageSize = pageSize; W+i^tmj
} y[XD=j
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publicint getTotalCount(){ 0ZjT.Ep
return totalCount; q8$t4_pF
} NAD^10
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publicvoid setTotalCount(int totalCount){ iW6O9~
if(totalCount > 0){ ?1ey$SSU]
this.totalCount = totalCount; `NQ
int count = totalCount / futYMoV
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pageSize; 9&*
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if(totalCount % pageSize > 0) L"'=[O~
count++; -4x! #|]
indexes = newint[count]; &`qYe)1Eo
for(int i = 0; i < count; i++){ TAUl{??,
indexes = pageSize * 4+hNP'e
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i; -
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} [k$GUU,jY
}else{ lWc[Q1
this.totalCount = 0; nDvfb*\
} sc]#T)xG
} {O>Td9
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publicint[] getIndexes(){ ]ePg6
return indexes; wK2$hsque
} X}Q4;='C-
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publicvoid setIndexes(int[] indexes){ us.[wp'Sh
this.indexes = indexes; Hpix:To
} +1wEoU.l2
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publicint getStartIndex(){ n=-vOa%
return startIndex; (LK@w9)i;
} wxHd^b
X.#*+k3s0
publicvoid setStartIndex(int startIndex){ y7pBcyWTE=
if(totalCount <= 0) OFr"RGW"
this.startIndex = 0; QqF<HCO
elseif(startIndex >= totalCount) sN1H{W
this.startIndex = indexes ;cVK2'
igQzL*X
[indexes.length - 1]; = -oP,$k
elseif(startIndex < 0) yr},pB
this.startIndex = 0; p^Ey6,!8]D
else{ S!A:/(^WB
this.startIndex = indexes @2"uJ6o
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[startIndex / pageSize]; #v(As)4^
} DTC
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} FZgf"XM>
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publicint getNextIndex(){ sFZdj0tQ4
int nextIndex = getStartIndex() + $@6q5Iz!&
( 72%au
pageSize; Dl.<(/
if(nextIndex >= totalCount) Vb?wwx7=
return getStartIndex(); dXDyY
else q2xAx1R`sV
return nextIndex; iY`[dsT
} t?&;
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publicint getPreviousIndex(){ 7a_8007$l
int previousIndex = getStartIndex() - imADjBR]
1CJ1-]S(3
pageSize; pzRVX8
if(previousIndex < 0) jy~hLEt7
return0; Uhvy2}w
else YN)qMI_`A
return previousIndex; Pm P&Qje7
} 9=}#.W3.
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} Gu{1%bb#kL
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抽象业务类 Fdl0V:<
java代码: f]10^y5&
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/** gGNo!'o
* Created on 2005-7-12 9+(6/<
*/ KOR*y(* 8
package com.javaeye.common.business; EiD41N
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import java.io.Serializable; KYkS^v
import java.util.List; 0;a1 0b
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import org.hibernate.Criteria; e lM<S3
import org.hibernate.HibernateException; UHV"<9tk
import org.hibernate.Session; \gT({XU?
import org.hibernate.criterion.DetachedCriteria; @RB^m(> 5
import org.hibernate.criterion.Projections; !gyW15z'
import t(UBs-t
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org.springframework.orm.hibernate3.HibernateCallback; M`7lYw\Or!
import @ebY_*
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org.springframework.orm.hibernate3.support.HibernateDaoS k_1;YOBF
D
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upport; 7&etnQJ{
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import com.javaeye.common.util.PaginationSupport; Bs3&yEq(
*pO`sC>
public abstract class AbstractManager extends bfb9A+]3'
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HibernateDaoSupport { hH$9GL{H
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privateboolean cacheQueries = false; tHqa%
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privateString queryCacheRegion; I7h v'3u
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publicvoid setCacheQueries(boolean j7Zv"Vq@
wtL=^
cacheQueries){ ~"bBwPI
this.cacheQueries = cacheQueries; Wf?[GO
} 1e9~):C~W
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publicvoid setQueryCacheRegion(String 1.,KN:qe
t\:=|t,
queryCacheRegion){ ;fQIaE&H
this.queryCacheRegion = "\lOOp^-
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queryCacheRegion; 6[FXgCb
} <D& Ep
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publicvoid save(finalObject entity){ lRS'M,/
getHibernateTemplate().save(entity); )~xH!%4F
} lV./K;\T
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publicvoid persist(finalObject entity){ N.|zz)y
getHibernateTemplate().save(entity); mDt!b6N/
} ]#S<]v A
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publicvoid update(finalObject entity){ Jzp|#*~$E
getHibernateTemplate().update(entity); $BLd>gTzmv
} /&qE,>hd.+
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publicvoid delete(finalObject entity){ o*~=NoR
getHibernateTemplate().delete(entity); O<AGAD
} <v\$r2C*
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publicObject load(finalClass entity, FBrh!vQ<
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finalSerializable id){ <h|&7
return getHibernateTemplate().load %"#ydOy
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(entity, id); jMX+uYx M
} ',D%,N}J
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publicObject get(finalClass entity, @5??`n
@ I&k|\
finalSerializable id){ qm9=Ga5
return getHibernateTemplate().get D#,A_GA{A
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(entity, id); %LqT>HXJ
} k:mW ,s|a
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publicList findAll(finalClass entity){ Ew;AYZX
return getHibernateTemplate().find("from l"h6e$dP
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:
" + entity.getName()); p?
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} Ai:,cY5%
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publicList findByNamedQuery(finalString ^P.U_2&
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namedQuery){ VV[Fb9W ;
return getHibernateTemplate *6}'bdQbNP
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().findByNamedQuery(namedQuery); 1<Uv4S
} z X+i2,
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publicList findByNamedQuery(finalString query, Ofb&W
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finalObject parameter){ WFmW[< g
return getHibernateTemplate 3:c6x kaw
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().findByNamedQuery(query, parameter); V~-tp^
} 3_&s'sG5
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publicList findByNamedQuery(finalString query, 0\k{v
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finalObject[] parameters){ A^|~>9
return getHibernateTemplate y\:Ma7V
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et
().findByNamedQuery(query, parameters); k O.iJcZg
} f"4w@X2F
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publicList find(finalString query){ ExFz@6@
return getHibernateTemplate().find "d0D8B7HI@
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(query); &
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} j]mnH`#BL
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publicList find(finalString query, finalObject Z;;A#h'%e
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parameter){ T}"[f/:N/
return getHibernateTemplate().find }P\6}cK
3".#nN
(query, parameter); l?xd3Z@7[
} ]1[:fQF7/L
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public PaginationSupport findPageByCriteria @W, <8
/*"pylm
(final DetachedCriteria detachedCriteria){ :/"5x
return findPageByCriteria iMV=R2t 2
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Q^xk]~G$(
} }Q6o#oZ
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public PaginationSupport findPageByCriteria [e{W:7uFV
*.T?#H
(final DetachedCriteria detachedCriteria, finalint )tS;gn
{([`[7B>a<
startIndex){ <33,0."K
return findPageByCriteria F]0
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(detachedCriteria, PaginationSupport.PAGESIZE, Z@>kqJ%
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startIndex); <qI!Dj{
} b9v<Jk
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public PaginationSupport findPageByCriteria ao|n<*}
e3[Q6d&|
(final DetachedCriteria detachedCriteria, finalint 8NJT:6Q7l
$(*>]PC+)
pageSize, :"@-Bcln
finalint startIndex){ 8L6b:$Y3@C
return(PaginationSupport) g^\!> i
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getHibernateTemplate().execute(new HibernateCallback(){ Tv
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publicObject doInHibernate pEW~zl
NQvI=R-g
(Session session)throws HibernateException { DhsvN&yNM
Criteria criteria = !?|xeQ}
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detachedCriteria.getExecutableCriteria(session); >
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int totalCount = _]eyt_
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((Integer) criteria.setProjection(Projections.rowCount ',rK\&lL6
S a}P
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()).uniqueResult()).intValue(); cz|?j
criteria.setProjection @*|T(068&
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(null); NBLjBa%eL
List items = |WOc0M[U
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criteria.setFirstResult(startIndex).setMaxResults )V_;]9<wt
B$hog_=s
(pageSize).list(); <num!@2D
PaginationSupport ps = nI1(2a1
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new PaginationSupport(items, totalCount, pageSize, Bx5kqHp^1
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startIndex); Sn'
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return ps; L1y71+iqU
} Vobq|Rd/%
}, true); .;l`VWP
} o)R<sT
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public List findAllByCriteria(final l/\D0\x2
AD@ {7
DetachedCriteria detachedCriteria){ Z aS29}
return(List) getHibernateTemplate KCH`=lX
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().execute(new HibernateCallback(){ tE-g]y3
publicObject doInHibernate 1xh7KBr,
t%<y^Wa=
(Session session)throws HibernateException { >[~7fxjK-
Criteria criteria = t`>Z#=cl\
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detachedCriteria.getExecutableCriteria(session); 5OX[)Li
return criteria.list(); !+QfQghAT
} %&q}5Y4!
}, true); nb6Y/`G
} KeXt"U
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public int getCountByCriteria(final _aJKt3GQ
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DetachedCriteria detachedCriteria){ kQQDaZ8
Integer count = (Integer) *v?kp>O
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getHibernateTemplate().execute(new HibernateCallback(){ mm.%Dcn
publicObject doInHibernate 7?y7fwER
HPJHA ,
(Session session)throws HibernateException { LIQ].VxIs
Criteria criteria = f*9O39&|
7q5*grm
detachedCriteria.getExecutableCriteria(session); 5O
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return y~VI,82*
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criteria.setProjection(Projections.rowCount )S/=5Uc
z0 #2?o
()).uniqueResult(); ,CuWQ'H
} qPN9Put
}, true); )feZ&G]
return count.intValue(); n=AcN
} 2i1xSKRYrD
} &ODo7@v`1
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用户在web层构造查询条件detachedCriteria,和可选的 HXztEEK6
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 _{gqi$Mi
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PaginationSupport的实例ps。 GNq
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ps.getItems()得到已分页好的结果集 L[,19;(
ps.getIndexes()得到分页索引的数组 u]9\_{c]Q
ps.getTotalCount()得到总结果数 sowwXrECg@
ps.getStartIndex()当前分页索引 qMA-#
ps.getNextIndex()下一页索引 *f`P7q*
ps.getPreviousIndex()上一页索引 ~id:Rh>o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 h:r?:C>n
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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 Q~VM.G
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一下代码重构了。 u*rP8GuS
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我把原本我的做法也提供出来供大家讨论吧: Ke?,AWfG
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首先,为了实现分页查询,我封装了一个Page类: +@?'dw
java代码: uLWu. Vx
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/*Created on 2005-4-14*/ #jW=K&;
package org.flyware.util.page; TjYHoL5
y_=y%
/** #kq!{5,
* @author Joa x\8|A
* 3}F>t{FDk
*/ El;"7Qn
publicclass Page { <r$h =hM
MGt>:&s(]
/** imply if the page has previous page */ #
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privateboolean hasPrePage; ck5cO-1>6
c@3 5\!9
/** imply if the page has next page */ [|=M<>?[
privateboolean hasNextPage; yNP4Ey
V-n{=8s
/** the number of every page */ zqXF`MAB=
privateint everyPage; }^ ,D~b-nB
"wTCO1
/** the total page number */ {7z]+ h
privateint totalPage; #S'uqP!
Br7q.
/** the number of current page */ d(d<@cB9
privateint currentPage; /bB4ec8!
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/** the begin index of the records by the current s(3HZ>qx;
tm^joK[{|J
query */ ZL\^J8PRK
privateint beginIndex; o,dp{+({
9&AO
Oh p@ZJ!a?
/** The default constructor */ ,}gJY^X+
public Page(){ 6&ut r!\7
e'G=.:
} 1p$(\
"8ellKh
/** construct the page by everyPage Kq-1 b
* @param everyPage n9}BT^4 v
* */ 85q/|9D
public Page(int everyPage){ ]h(Iun
this.everyPage = everyPage; Td'(RV
} $S|+U}]C
d$3md<lIB
/** The whole constructor */ Zja3HGL
public Page(boolean hasPrePage, boolean hasNextPage, AG=PbY9
0P9\; !Y
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int everyPage, int totalPage, Cd
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int currentPage, int beginIndex){ ;Jg$C~3tf
this.hasPrePage = hasPrePage; \2 N;VE
this.hasNextPage = hasNextPage; %bN{FKNN
this.everyPage = everyPage; LkS tU)
this.totalPage = totalPage; eTvjo(Lvx
this.currentPage = currentPage; ZZI}
Ot{
this.beginIndex = beginIndex; +u0of^}=
}
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s.i9&1Y-!
/** WF~BCP$OR
* @return z}u`45W+
* Returns the beginIndex. "I/05k K
*/ s_IFl5D]
publicint getBeginIndex(){ /-[vC$B"
return beginIndex; iIX%%r+
} A'z]?xQR
Ia}qDGqPp!
/** >B**fZ~L
* @param beginIndex ZY`9
* The beginIndex to set. Uq#2~0n>
*/ %Tp
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publicvoid setBeginIndex(int beginIndex){ 3Z9Yzv)A
this.beginIndex = beginIndex; 92<+ug =
} = +MF@ 4
JP<j4/
/** M1-tRF
* @return sPvs}}Z]P
* Returns the currentPage. mB_?N $K
*/ B+Qf?1f
publicint getCurrentPage(){ ;QXg*GNAv$
return currentPage; :5%98V>02
} bTimJp[b
C`i#7zsH
/** =|1_6.tz
* @param currentPage KqntOo}
y)
* The currentPage to set. n~ad#iN
*/ `~)?OTzU#
publicvoid setCurrentPage(int currentPage){ ?DUim1KG
this.currentPage = currentPage; HZRFE[ 9nb
} L?N&kzA
,W)DQwAg
/** MSS[-}
* @return ?YL JXq
* Returns the everyPage. F8-GnTxa
*/ SED52$zA
publicint getEveryPage(){ Wn@oG@}~
return everyPage; c8X;4
My
} >2{Y5__+e
q@bye4Ry%W
/** 'fU #v`i
* @param everyPage p-.kBF
* The everyPage to set. O^8ZnN_+
*/ ;O`f+rG~
publicvoid setEveryPage(int everyPage){ dfdK%/' $(
this.everyPage = everyPage; e7;7TrB.
} :KO&j"[
j;`Q82V\
/** Hvk~BP'
m
* @return /ZV2f3;t
* Returns the hasNextPage. P-4$Qksx
*/ 3=uhy|f! /
publicboolean getHasNextPage(){ 7@<.~*Bl6
return hasNextPage; EO)JMV?6
} G]rY1f0
t/Io.d
/** MygAmV&
* @param hasNextPage M@{?#MkS%
* The hasNextPage to set. Y
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*/ xcW\U^1d
publicvoid setHasNextPage(boolean hasNextPage){ 1}wDc$O
this.hasNextPage = hasNextPage; 9lYfII}4(
} 0"OEOYs}
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/** 0o>C,
`
* @return {FvFah
* Returns the hasPrePage. 5/'Q0]4h
*/ hxL?6mhY
publicboolean getHasPrePage(){ b:F;6X0~Hl
return hasPrePage; PEvY3F}_rh
} [oU\l+t
f5 bq)Pm&
/** vmAnBY
* @param hasPrePage *xNc^&.
* The hasPrePage to set. 1}\p:`
*/ 3Sfd|0^
publicvoid setHasPrePage(boolean hasPrePage){ k^%=\c
this.hasPrePage = hasPrePage; LhLAQ2~
} ; H ;h[
/lC# !$9vz
/** _rYW|*cIF
* @return Returns the totalPage. h-ii-c?R@0
* r!Dk_|Cd
*/ Hdew5Xn(:
publicint getTotalPage(){ -yqgs>R(d
return totalPage; A3/[9}(U
} gDU!dT
@l j|
/** EX_j|/&tZ
* @param totalPage LMoZI0)x
* The totalPage to set. zr?s5RS
*/ 7!AyL w
publicvoid setTotalPage(int totalPage){ j<(E%KN3
this.totalPage = totalPage; 0V<kpC,4
} kMVr[q,MEq
6ncwa<q5
} e&
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_:9}RT?
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e}?Q&Lci
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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 [Kc ?<3W
j<kW+Iio
个PageUtil,负责对Page对象进行构造: Am*IC?@tq
java代码: B%\&Q@X
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/*Created on 2005-4-14*/ Nt$4;
package org.flyware.util.page; ]YI9
u1X^#K$nu'
import org.apache.commons.logging.Log; 9o>D
Uc
import org.apache.commons.logging.LogFactory; CPy>sV3Ru0
>)M1X?HI5
/** +45SKu=
* @author Joa ;:bp?(
* M584dMM
*/ 5{b;wLi$X2
publicclass PageUtil { O;RBK&P
I4@XOwl{P
privatestaticfinal Log logger = LogFactory.getLog 1@OpvO5
bss2<mqlH
(PageUtil.class); d?X,od6
fr(Ja;
/** X?t;uZI^
* Use the origin page to create a new page $(D>v!dp
* @param page 5.VPK 338A
* @param totalRecords eaf-_#qb
* @return ]#G s6CsT|
*/ eAW)|=2
publicstatic Page createPage(Page page, int :^kAFLU
a,oTU\m
C
totalRecords){ PoaCnoNS
return createPage(page.getEveryPage(), kZG=C6a
KE,.Evyu=
page.getCurrentPage(), totalRecords); /o4e
n
} 7~P2q/2E>
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/** Chnt)N`/B4
* the basic page utils not including exception ~NIhS!
CqEbQ>?
handler &fB=&jc*j
* @param everyPage GPLop/6
* @param currentPage |j0_^:2r=
* @param totalRecords Q*<KX2O
* @return page 7<WUjK|
*/ A2gFY}
publicstatic Page createPage(int everyPage, int j?u1\<m
_3%$E.Q
currentPage, int totalRecords){ ;7s^slVzF
everyPage = getEveryPage(everyPage); _{'[Uf/l
currentPage = getCurrentPage(currentPage); +m./RlQ{
int beginIndex = getBeginIndex(everyPage, jz"
>Kh.}
ZS+m}.,whQ
currentPage); 8i[TeW"
int totalPage = getTotalPage(everyPage, Kuh3.1#o
H(;@7dh
totalRecords); $!wU[/k
boolean hasNextPage = hasNextPage(currentPage, zlEI_th:~
-sA&1n"W&5
totalPage); o;6~pw%
boolean hasPrePage = hasPrePage(currentPage); PpFQoY7M
h.R46 :
returnnew Page(hasPrePage, hasNextPage, O W.CU=XU
everyPage, totalPage, 2?7ID~\
currentPage, K@=u F1?
pv0|6X?J"
beginIndex); }+m4(lpl
} Ydrh+
2 %fcDEG/
privatestaticint getEveryPage(int everyPage){ # l9VTzi
return everyPage == 0 ? 10 : everyPage; m^XO77"
} yn!;Z._
Zocuc"j
privatestaticint getCurrentPage(int currentPage){ XFoSGqD
return currentPage == 0 ? 1 : currentPage; J\+fkN<.
} Xd A]);,
I<RARB-j
privatestaticint getBeginIndex(int everyPage, int ]CNPy$>*
bxYSZCo*
currentPage){ mQ1
return(currentPage - 1) * everyPage; TXM/+sd
} H^kOwmSzh
O$,
privatestaticint getTotalPage(int everyPage, int \\ItN
*
;sz/.
totalRecords){ 6rbR0dSgx
int totalPage = 0; s/@uGC0>
pBe1:
if(totalRecords % everyPage == 0) ]d(Z%
totalPage = totalRecords / everyPage; Vq0X:<9
else F_:Wu,dUZ
totalPage = totalRecords / everyPage + 1 ; cr -5t4<jK
KJJ:fG8'
return totalPage; {wM<i
} XE_Lz2H`
4~1b
privatestaticboolean hasPrePage(int currentPage){ KKk~vwW
return currentPage == 1 ? false : true; 9~=zD9,|iA
} %0y-f
Lbo3fwW
privatestaticboolean hasNextPage(int currentPage, 5yt= ~
i
Ehc<
int totalPage){ [ p,]/ ^ N
return currentPage == totalPage || totalPage == |e!Y
C iU
8Kl&_-l{b
0 ? false : true; O9N!SQs80
} @BLB.=
g~-IT&O
>k\p%{P
} }ACg#;>/+
H HX q_-V
$hCS-9%&
#Ev}Gf+5Q
\3ydNgl
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 aJv+BX_,
0.+Eo.AX4M
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 i?d545. u
<v9IK$J
做法如下: wM[Z 0*K
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 xKBi".wA
JtSwbdN
的信息,和一个结果集List: =LIb0TZ2
java代码: IR3SP[K"
v(Kj6 '
0=
bXL!]
/*Created on 2005-6-13*/ LkHH7Pd@
package com.adt.bo; 7./-|#
Efe(tH2q
import java.util.List; +cXi|Zf
8h)7K/!\
import org.flyware.util.page.Page; mI<s f?.
Xk!{UxQKQ
/** 0x5\{f
* @author Joa <WWZb\"{
*/ 4/{pz$
publicclass Result { OH`zeI,[*
VFawASwQ
private Page page; FT>>XP8
!W,LG$=/
private List content; -wH0g^Ed
R#Yj%$E1
/** E4\HI+
* The default constructor A#']e 8
*/ ,)U%6=o#}
public Result(){ eQyc<
super(); SN")u
} }9U_4k
\c{sG\ >
/** oH4zW5
* The constructor using fields /+B6oE>8
* fup?Mg-
* @param page HZ!<dy3
* @param content V%;dTCq
*/ Rf)|p;
public Result(Page page, List content){ XySkm2y
this.page = page; /ho7~C+H*e
this.content = content; #X``^
} ;2`t0#J$]
W\0u[IV.x
/** ' xaPahx;
* @return Returns the content. %j@/Tx/
*/ *qL'WrB1
publicList getContent(){ M`Wk@t6>
return content; q},,[t
} T1RY1hb|g>
v1+.-hO
/** h8M_Uk
* @return Returns the page. 9
4bDJy1
*/ 1NZpd'$c
public Page getPage(){ L~h:>I+pG
return page; 7s%1?$B
} 0n4( Rj|}2
=n=!s{A:t
/** n(LO`{
* @param content [vuikJP>1k
* The content to set. im+g|9@%
*/ H/ e jO_{
public void setContent(List content){ }jce5E
this.content = content; ^wSGrV'
} -/B*\X[
&)Zv>P8z`
/** 6^jrv [d
* @param page ;D-k\kv
* The page to set. Omn$O>
*/ hxJKYU^%m
publicvoid setPage(Page page){ n]3'N58
this.page = page; Q$:,N=%
} -f:PgBj
} GHLFn~z@XJ
sAA;d
$z)egh(z
>(YH@Z&;
"p+oi@
2. 编写业务逻辑接口,并实现它(UserManager, iM9k!u FE
xrY >Or
UserManagerImpl) c>c4IQ&d
java代码: >e.vUUQ{
yXtQfR
E*tT^x)
/*Created on 2005-7-15*/ ;InMgo,
package com.adt.service; &'DR`e O)
D8B\F5..c#
import net.sf.hibernate.HibernateException; ]RadwH"0!
>D##94PZ
import org.flyware.util.page.Page; h<'tQGC
Kx[+$Qt
import com.adt.bo.Result; DH$Nz
XmVst*2=
/** `z/p,. u
* @author Joa N5#j}tT
*/ ,G?Kb#
publicinterface UserManager { P A*U\
Q>\DM'{:4
public Result listUser(Page page)throws OFcP4hDi
=SW <Vhtb
HibernateException; r-WX("Vvh
8In~qf
} F!?f|z,/
i-WP#\s
&>Y.$eW_
|yj0Rv
wwR}h I(
java代码: ]<%NX
$9\
gd%Ho8,T
+g1+,?cU
/*Created on 2005-7-15*/ >#T?]5Z'MF
package com.adt.service.impl; xu]Kt+QnSk
FL$S_JAw
import java.util.List; 1B 0[dK2N
n#?y;Y\
import net.sf.hibernate.HibernateException; #IqRu:csp
V!@6Nv
import org.flyware.util.page.Page; FSkX95
import org.flyware.util.page.PageUtil; 6"[,
m^RO*n.
import com.adt.bo.Result; {SZv#MrK
import com.adt.dao.UserDAO; vkYiO]y
import com.adt.exception.ObjectNotFoundException; g^=Ruh+
import com.adt.service.UserManager; <O-R
Sy*p6DP
/** eAQ-r\h'2
* @author Joa Z)3oiLmD
*/ |hDN$By
publicclass UserManagerImpl implements UserManager { 0x&L'&SpN
]gA2.,)}D
private UserDAO userDAO; #c/K.?
BOdlz#&s
/** WkpHe
* @param userDAO The userDAO to set. )#? K2E
*/ /
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publicvoid setUserDAO(UserDAO userDAO){ \x\(36\u
this.userDAO = userDAO; @,G\`;Ma
} LH@Kn?R6
2>CR]
/* (non-Javadoc) HB<>x
* @see com.adt.service.UserManager#listUser +n
&8" )
F,mStw:
(org.flyware.util.page.Page) <
jX5}@`z
*/ *xx)j:Sc2
public Result listUser(Page page)throws r0\C2g_X
{8;}y[R
HibernateException, ObjectNotFoundException { B1Z;
int totalRecords = userDAO.getUserCount(); -" r4
if(totalRecords == 0) ][ 8`}ki 1
throw new ObjectNotFoundException p gv, Su
cxPO O#
("userNotExist"); mgq4g
page = PageUtil.createPage(page, totalRecords); tC=K;zsXpz
List users = userDAO.getUserByPage(page); d7Cs a
c
returnnew Result(page, users); c[vFh0s"m
} ?l|&JgJ$
v(uNqX.BC
} @y
eAM7
\^'-=8<*>
t`eIkq|NxI
T$DFTr\\
G8Ow;:Ro
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ':=20V
m.5@qmQ
询,接下来编写UserDAO的代码: eG dFupfz
3. UserDAO 和 UserDAOImpl: ).tTDZ
java代码: h>z5m
tC/+
)2jH&}K
/*Created on 2005-7-15*/ wr>6Go%
package com.adt.dao; 'OU3-K
:$XlYJrjK
import java.util.List; -<u_fv
gEgd/Le
import org.flyware.util.page.Page; 5RF*c,cNq
BISH34
import net.sf.hibernate.HibernateException; =""5
c
je>mAQKi\
/** G}]'}FUp
* @author Joa [xdVuL;N
*/ +mO/9m
publicinterface UserDAO extends BaseDAO { *~UK5Brf1
z4]z3U<}3]
publicList getUserByName(String name)throws AZ\f6r{
J'wJe,
HibernateException; >@Na6BH5v
|b!Bb<5
publicint getUserCount()throws HibernateException; xHkx rXqeI
4dI`
publicList getUserByPage(Page page)throws b>}
)G7b}
i\K88B&24
HibernateException; ,n UovWN07
Q[T)jo,j%
} D~2n8h"2ye
g6][N{xW0
S}
&1_I
T7?z0DKi
5m>f1`4JS
java代码: t<^7s9r;I
3)(uC+?[
7G Jhc
/*Created on 2005-7-15*/ 1 a%1C`d
package com.adt.dao.impl; #A<
|qd
Iqj?wI1)
import java.util.List; @k-GyV-v
,K.Wni#m
import org.flyware.util.page.Page; |A=~aQot
:vFYqoCn
import net.sf.hibernate.HibernateException; {Bpu-R&T
import net.sf.hibernate.Query; >GDf*
ox[
vU#>3[aC
import com.adt.dao.UserDAO; E6?0/"
4Ub7T=LG
/** raR=k!3i
* @author Joa 'SWK{t \4
*/ 8b25D|8l
public class UserDAOImpl extends BaseDAOHibernateImpl wZj`V_3
hu~XFRw15
implements UserDAO { ji5Nq+S2
$A98h-*x
/* (non-Javadoc) k+eeVy
* @see com.adt.dao.UserDAO#getUserByName
1<0Z@D~F
B2)5Z]
(java.lang.String) @|d`n\%x
*/ IL%P\Zs
publicList getUserByName(String name)throws 7v`~;}5
4y,pzQ8a
HibernateException { U@}P]'`'f
String querySentence = "FROM user in class aL8Z|*
K[q-[q#yc
com.adt.po.User WHERE user.name=:name"; PD^Cj?wm
Query query = getSession().createQuery ztC,[
tSTl#xy
(querySentence); 8`|Z9umW*
query.setParameter("name", name); /!hxW}>^
return query.list(); gjB(Pwx
} @M(+YCi:e@
[QwqP=-6
/* (non-Javadoc) V$ "]f6
* @see com.adt.dao.UserDAO#getUserCount() UrdSo"%
*/ ERfSJ
publicint getUserCount()throws HibernateException { -Y>QKS
int count = 0; ;jmT5XzL
String querySentence = "SELECT count(*) FROM #*"I?B/fd8
8HWEObRY
user in class com.adt.po.User"; K/!>[d
Query query = getSession().createQuery 2:1
kSR^Ky
EB
p(^rj
(querySentence); 2=n,{rkmj%
count = ((Integer)query.iterate().next $N4i)>&T2
cM=_i{c
()).intValue(); M1K[6V!
return count; Ge*N%=MX8
} 4B-+DH>{6
Fw%S%*B8g
/* (non-Javadoc) 'D^@e0.3
* @see com.adt.dao.UserDAO#getUserByPage z2;<i|Ez0
!*,m=*[3
(org.flyware.util.page.Page) N1dM,H
*/ E$4Ik.k
publicList getUserByPage(Page page)throws wqJ1^>TB
'.XR,\g>
HibernateException { wHs4~"EY9
String querySentence = "FROM user in class @-O%u*%J
r3~YGY
com.adt.po.User"; =^w:G =ymS
Query query = getSession().createQuery `OWwqLoeA
%eJE@$
(querySentence); vZ|Wj] ;o
query.setFirstResult(page.getBeginIndex()) *>jJ<8!
.setMaxResults(page.getEveryPage()); MVp+2@)}s
return query.list(); t28 y=nv
} `Oe}OSxnT
p$$0**p!`
} 88zK)k{
E> YE3-]
rKr\Qy+q
O?Qi
B1J2m^
至此,一个完整的分页程序完成。前台的只需要调用 mHc5NkvQC
gV-A+;u
userManager.listUser(page)即可得到一个Page对象和结果集对象 Yi|Nd ;
Ne}x(uRn
的综合体,而传入的参数page对象则可以由前台传入,如果用 h?vt6t9
FivqyT7i
webwork,甚至可以直接在配置文件中指定。 |p*s:*TJp
F2',3
下面给出一个webwork调用示例: %5<Xa
java代码: y+M9{[ i/O
@zig{b 8
>8gb/?z
/*Created on 2005-6-17*/ Q\z9\mMG-
package com.adt.action.user; F?4&qbdD
i5czm?x
import java.util.List; UQJ
3moDu
import org.apache.commons.logging.Log; o#V{mm,{Pm
import org.apache.commons.logging.LogFactory; WCg&*
import org.flyware.util.page.Page; Q&&oP:4~X*
{BD G;e
import com.adt.bo.Result; x,QXOh\a
import com.adt.service.UserService; rf
=Wq_
import com.opensymphony.xwork.Action; o AM)<#U>
Uq(fk9`6
/** TL: 6Pe
* @author Joa R(GL{Dh}L
*/ +3r4GEa
Z
publicclass ListUser implementsAction{ +w(B9rH
6f;20dn6
privatestaticfinal Log logger = LogFactory.getLog m@g9+7
EskD)Sl
(ListUser.class); OTWp,$YA=
@}_Wl<kn
private UserService userService; Z':w
X
WdT iao,r
private Page page; Z (C0+A\
bfKF6
privateList users; =dY!-#yg!
KKNQ+'?
/* nRheByYm
* (non-Javadoc) vFi+ExBU
* fD2)/5j1
* @see com.opensymphony.xwork.Action#execute() 7~nuFJaTI
*/ 0W]vK$\F*
publicString execute()throwsException{ /(DnMHn\
Result result = userService.listUser(page); 6Vu)
page = result.getPage(); rWip[>^
users = result.getContent(); B[;aNyd<
return SUCCESS; 6rN.)dL.#N
} [(Ihu e
H~lvUHN
/** 9QEK|x`8
* @return Returns the page. ;~( yv|f6
*/ ]eo%eaA
public Page getPage(){ >4nQ&b.u
return page; Eb9n6Fg
} 4ms"mIt
@8lT*O2j
/** jXYjs8Iy
* @return Returns the users. @$5=4HA
*/ 1i;#cIG
publicList getUsers(){ X1^Q1?0
return users; !PJp()
} PgYIQpV
&|fWtl;43
/** 'oF ('uR
* @param page *)s^+F 0
* The page to set. ]+T$D
*/ QQ./!
publicvoid setPage(Page page){ F?b"Rv
this.page = page; FA}y"I'W
} ;.3
{}.Y
3shd0q<
/** P}"uC`036
* @param users )8_MkFQe
* The users to set. Y
{|is2M9'
*/ n {..Q,z
publicvoid setUsers(List users){ =JN{j2xY
this.users = users; UZJ#/x5F
} +3]V>Mv
ln_[@K[oX
/** a.fdCI]%
* @param userService S#S&_#$`,X
* The userService to set. mi@ni+2Tn
*/ L`"V_
"Q#0
publicvoid setUserService(UserService userService){ T%SK";PAU$
this.userService = userService; u0nIr9
} -v$ q8_$m"
} #hXxrN
R_Z9aQ
TVAa/_y2`
Fmzkbt~oe
XUTsW,WC
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, o&>aYlXd
06[HE7
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ^m -w@0^z
|cL,$G
么只需要: ;3+_aoY
java代码: @x_0AkZU
gpogv
-
c"/Hv
<?xml version="1.0"?> a7jE*%f9
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork mEyIbMci
=Jswd
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C0CJ;
+HlZ?1g
1.0.dtd"> 9hjzOJPuga
Zm6|aHx8v
<xwork> +g_m|LF
7MQxW<0
<package name="user" extends="webwork- Wjr^: d
Av!xI
interceptors"> |v_ttJ;+Y
LR3>_t
<!-- The default interceptor stack name RM>A9nv$\
vK$wc~
--> aev(CY,z
<default-interceptor-ref ]U,m
1
@ ?bY,
name="myDefaultWebStack"/> =ba1::18
|nBZ :$D
<action name="listUser" '3xK1Am
l YpoS
class="com.adt.action.user.ListUser"> gi$ 'x^]#
<param #x \YA#~
2x~Pq_?y
name="page.everyPage">10</param> vb3hDy
<result 8WC_CAP
0bteI*L
name="success">/user/user_list.jsp</result> ZtY?X- 4_
</action> ~Gl5O`w(
d
'\^S}
</package> 0 gR_1~3
^0?ww&X
</xwork> v
,zD52
15d'/f
dtig_s,)D
LQV&;O4'
g @NwW&
w!-MMT4y
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 C9*[/| T
m@2=vq1f
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。 gZ8JfA_\R(
. Ctd$
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 h=^UMat-
X$_pDF&\z
S3&n?\CO:
FsS.9
`B
*:ErZ UyQM
我写的一个用于分页的类,用了泛型了,hoho )nrYxxN
)>@%;\qV
java代码: rp|A88Q/!
35 L\
7MsJ*En
package com.intokr.util; LIT`~D
NDJP`FI
import java.util.List; t:b}Mo0
aLlHR_
/** @WiTh'w0
* 用于分页的类<br> c )=a;_h
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 4vV\vXT *
* KY?ujeF
* @version 0.01 WJMmt XO
* @author cheng 2w fkXS=~6
*/ wCu!dxT|,
public class Paginator<E> { 4/OmgBo'
privateint count = 0; // 总记录数 tlB-s;
privateint p = 1; // 页编号
n%Oq"`w4
privateint num = 20; // 每页的记录数 Q{CRy-ha
privateList<E> results = null; // 结果 ppGWh
@FF80U4'
/** `qRyh}Ax"
* 结果总数 >=;hnLu
*/ `U&'71B^
publicint getCount(){ 1L?d/j
return count; 3#y`6e=5
} [z!pm-Ir
`G%h=rr^c
publicvoid setCount(int count){ %evtIU<h
this.count = count; kSEgq<i!
} 4p%^?L?
x,|fblQz
/** trB-(B%5
* 本结果所在的页码,从1开始 VF g(:
* .[Qi4jm>`
* @return Returns the pageNo. .&I!2F
*/ tH#t8Tq5x
publicint getP(){ N1sdWXG
return p; r! [Qpb-:
} xzOn[.Fi
`gyke2n
/** /F6"uZSt4
* if(p<=0) p=1 q_9 8=fyE6
* .{|SKhXk
* @param p FR>[g`1
*/ /U-+ClZi@
publicvoid setP(int p){ Cq'{%
if(p <= 0) HTMg{_r(%
p = 1; W8r"dK
this.p = p; bZ^'_OOn
} Rt5pl,Nf
v6Wz:|G/u
/** v*c"SI=@M=
* 每页记录数量 lJ,\^\q
*/ 8kvA^r`
publicint getNum(){ >V4r'9I
return num; e)m6xiZ
} :))&"GY
1Zi` \N4T
/** ]9c{qm}y
* if(num<1) num=1 Mpco8b-b
*/ G~ LQM
publicvoid setNum(int num){ ,_s.amL3O{
if(num < 1) fjY:u,5V_
num = 1; oOaLD{g>
this.num = num; ^bfU>02Q6p
} 4wGBB{X
5evk_f
/** Zj_2B_|WN#
* 获得总页数 L,ax^]
*/ wG6Oz2(
publicint getPageNum(){ pred{HEye
return(count - 1) / num + 1; h:sf?X[
} Db;>MWt+e
'-Oh$hqCx|
/** U#Iwe=
* 获得本页的开始编号,为 (p-1)*num+1 ovdaK"q2
*/ 5.DmMG[T^=
publicint getStart(){ 2%J] })
return(p - 1) * num + 1; R&g&BF
} h7@%}<%
RGkV%u^
/** f.bw A x
* @return Returns the results. }RKsS3}
*/
n_k`L(8*
publicList<E> getResults(){ A (p^Q
return results; BPm")DMo
} ~wOMT
Zsmv{p
public void setResults(List<E> results){ N9s.nu
this.results = results; qk>SM|{
} yeBfzKI{b
XsDZ<j%x89
public String toString(){ Ts3!mjn
StringBuilder buff = new StringBuilder 7oc Ng
"]Uj _d
(); Bjj=UtI
buff.append("{"); ~)[pL(4
buff.append("count:").append(count); 2oOos%0
buff.append(",p:").append(p); t
o8J
buff.append(",nump:").append(num); T 1_B0H2
buff.append(",results:").append G l2WbY
e@S$[,8
(results); Sw$/Z)1K&
buff.append("}"); Nl/
fvJ`4
return buff.toString(); H q?F @X
} ?L H[,8z
cfRUVe
} ^:mKTiA-
%M/L/_d
<|]i3_Z