Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $i1A470C
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 "VeUOdNA>
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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 1^;h:,e6
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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 M;9+L&p=
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分页支持类:
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java代码: sHuz10
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package com.javaeye.common.util; iF0a
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import java.util.List; <It7s1O
@}Ixr{t
publicclass PaginationSupport { $SXxAS1
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publicfinalstaticint PAGESIZE = 30; ;!}SgzSH}
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privateint pageSize = PAGESIZE; U,M,E@
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privateList items; p^:Lj 9Qax
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privateint totalCount; s,v#lJ]d0W
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privateint[] indexes = newint[0]; c 2@@Rd~M
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privateint startIndex = 0; &V3oW1*W
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public PaginationSupport(List items, int `Y;gMrp
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totalCount){ >l1Yhxd_0*
setPageSize(PAGESIZE); w3N%J>4_E
setTotalCount(totalCount); )r i3ds
setItems(items); AL7O -D
setStartIndex(0); lnWiE}F
} #<PdZl R
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public PaginationSupport(List items, int f5% &
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totalCount, int startIndex){ ug,|'<G+
setPageSize(PAGESIZE); Nj_sU0Dt
setTotalCount(totalCount);
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setItems(items); KL mB
setStartIndex(startIndex); emB D@r
} J\ +gd%
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public PaginationSupport(List items, int .4W>9
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totalCount, int pageSize, int startIndex){ ('-}"3
setPageSize(pageSize); U_;J.{n
setTotalCount(totalCount); <57l|}8
setItems(items); "EYjY->
setStartIndex(startIndex); 0r ;
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} K=?F3tX^
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publicList getItems(){ U<Y'.!
return items; Yb3f]4EH
} doO
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publicvoid setItems(List items){ fKz"z{\,0
this.items = items; 'xZPIj+
} kr`BUW3
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publicint getPageSize(){ <GgtP55
return pageSize; :KP'xf.
} B=bI'S8\
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publicvoid setPageSize(int pageSize){ UX'NJ1f
this.pageSize = pageSize; -0o6*?[Z
} UxcDDa/j2T
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publicint getTotalCount(){ B H0#Q5
return totalCount; ho]!G498
} MupW=3.38
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publicvoid setTotalCount(int totalCount){ sMS9!{A
if(totalCount > 0){ ;#yu"6{
this.totalCount = totalCount; 9X$#x90
int count = totalCount / J&"?m.~@
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pageSize; NVc!g
if(totalCount % pageSize > 0) 4%fN\f
count++; Ls>u`hG
indexes = newint[count]; }K/}(zuy1Y
for(int i = 0; i < count; i++){ ]fADaw-R
indexes = pageSize * :DMHezaU
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i; {y&\?'L'
} mfngbFa1
}else{ |)?aH2IL
this.totalCount = 0; g{v5mly
} U +*oI *
} Z;fm;X%4
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publicint[] getIndexes(){ >' ksXA4b
return indexes; OY^n0Zof,
} ;5D@kS^
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publicvoid setIndexes(int[] indexes){ QtnM(m
this.indexes = indexes; =XMD+
} hY.e [+
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publicint getStartIndex(){ ]g>m? \'n
return startIndex; U0h)pdo
} s%N`
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publicvoid setStartIndex(int startIndex){ d; mmM\3]
if(totalCount <= 0) mq
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this.startIndex = 0; ?qg^WDs$
elseif(startIndex >= totalCount)
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this.startIndex = indexes S2rEy2\}:
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[indexes.length - 1]; /nC{)s?S'
elseif(startIndex < 0) p}YI#f
in/
this.startIndex = 0; >JKnGeF
else{ %[]"QbF?
this.startIndex = indexes oLrkOn/aY
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[startIndex / pageSize]; ?G$Om
} iK5]y+@8
} +{,N X
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publicint getNextIndex(){ r6d0x
int nextIndex = getStartIndex() + k4qLB1&,
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pageSize; bz,Da
if(nextIndex >= totalCount) rc;7W:
return getStartIndex(); <i\UMrD]`:
else 42rj6m\
return nextIndex; NuC-qG#
} |d,F-9iw
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publicint getPreviousIndex(){ A",eS6
int previousIndex = getStartIndex() - zKIGWH=qqm
|-~b$nUe
pageSize; B#FHf
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if(previousIndex < 0) zP_ ]
return0; Mw/?wtW
else ]i-P-9PA4
return previousIndex; 3p:=xL
} 89hF)80
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} $Mdbto~ <
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抽象业务类 $aB/+,
java代码: TqIAWbb&
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/** ?#d6i$
* Created on 2005-7-12 :.Y|I[\E%
*/ DW#Bfo
package com.javaeye.common.business; }K2
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import java.io.Serializable; 2;8Xz6T
import java.util.List; Rv98\VD"
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import org.hibernate.Criteria; zG_p"Z7,
import org.hibernate.HibernateException; `)T&~2n
import org.hibernate.Session; Bp
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import org.hibernate.criterion.DetachedCriteria; tE@FvZC'=
import org.hibernate.criterion.Projections; l';pP^.q
import ;(7-WnU8N
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org.springframework.orm.hibernate3.HibernateCallback; ~8TF*3[}[
import 2Zy_5>~
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org.springframework.orm.hibernate3.support.HibernateDaoS nP<S6:s:
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upport; Ejv%,q/T(
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import com.javaeye.common.util.PaginationSupport; 5y]io
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public abstract class AbstractManager extends _K'7(d0z
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HibernateDaoSupport { k'Gw!p}
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privateboolean cacheQueries = false; v9=}S\=Cd
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privateString queryCacheRegion; $/+so;KD
% #u.J
publicvoid setCacheQueries(boolean l;OYUq~F
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cacheQueries){ /prYSRn8
this.cacheQueries = cacheQueries; <?YA,"~
} 9t?L\
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publicvoid setQueryCacheRegion(String >)NQH9'1
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queryCacheRegion){ \6o\+OQk
this.queryCacheRegion = 3+ =I;nj
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queryCacheRegion; /;Yy@oc
} nU2V]-qY
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publicvoid save(finalObject entity){ )s)_XL
getHibernateTemplate().save(entity); =LI:S|[4
} R(G\wqHUT3
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publicvoid persist(finalObject entity){ ?sXG17~Bm
getHibernateTemplate().save(entity); =\Iu$2r`
} Pz%~ST
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publicvoid update(finalObject entity){ 9cG<hX9`F
getHibernateTemplate().update(entity); ^]>aHz9
} l'6d4
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publicvoid delete(finalObject entity){ ^z~~VBv
getHibernateTemplate().delete(entity); +6l]] *H
} H=p`T+
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publicObject load(finalClass entity, "UG
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finalSerializable id){ e"k/d<
return getHibernateTemplate().load 5dl,co{q
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(entity, id); T_LLJ}6M
} @pFj9[N
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publicObject get(finalClass entity, n-J2/j
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finalSerializable id){ $i#?v
return getHibernateTemplate().get zXZir7NfM
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(entity, id); 8]bz(P#
} +&5'uAe
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publicList findAll(finalClass entity){ .Q* 'r&n
return getHibernateTemplate().find("from gmP9j)V6
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" + entity.getName()); BI/&dKM
} I4=Xb^Ux
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publicList findByNamedQuery(finalString =lp1Z>
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namedQuery){
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return getHibernateTemplate vWjnI*6T#
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().findByNamedQuery(namedQuery); ^zr^ N?a
} `VT>M@i/
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publicList findByNamedQuery(finalString query, "35A/V
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finalObject parameter){
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return getHibernateTemplate e,gyQjJR
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().findByNamedQuery(query, parameter); .c+9P<VmC}
} @?kJ).
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publicList findByNamedQuery(finalString query, Q@S-f:!
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finalObject[] parameters){ 3n]79+w@z
return getHibernateTemplate *
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().findByNamedQuery(query, parameters); UvJ;A
} MYdO jcN
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publicList find(finalString query){ h8{(KRa 6
return getHibernateTemplate().find B&0;4
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(query); @'6"7g
} /=: j9FF
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publicList find(finalString query, finalObject *ZrSiIPP
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parameter){ xHA0gZf
return getHibernateTemplate().find Fc 6iQ
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(query, parameter); 3=mr
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} A7Po 3n%Q
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public PaginationSupport findPageByCriteria -NJ!g/ >mM
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(final DetachedCriteria detachedCriteria){ neZ.`"LV
return findPageByCriteria nz]&a1"&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); i3$$,W!
} fyknP)21I
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public PaginationSupport findPageByCriteria EgjR^A1W2
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(final DetachedCriteria detachedCriteria, finalint (p#0)C
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startIndex){ 8'
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return findPageByCriteria [iP#VM-N
};L ^w:
(detachedCriteria, PaginationSupport.PAGESIZE, ^h' Sla
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startIndex); Yf@e=:
} L{-LX=G^
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public PaginationSupport findPageByCriteria W/$Zvl
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(final DetachedCriteria detachedCriteria, finalint PNs~[
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pageSize, Pe73g%
finalint startIndex){ >$WQxbwM(
return(PaginationSupport) $;N* c H~
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getHibernateTemplate().execute(new HibernateCallback(){ *cuuzi&
publicObject doInHibernate v=@TWEE
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(Session session)throws HibernateException { 8.AR.o
Criteria criteria = 9;.(u'y|
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detachedCriteria.getExecutableCriteria(session); b;sVls
int totalCount = F,BOgWwP
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((Integer) criteria.setProjection(Projections.rowCount "\C$
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()).uniqueResult()).intValue(); GzXUU@p
criteria.setProjection N["W Ir
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F
(null); *g}Yw
List items = YHkcWz
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criteria.setFirstResult(startIndex).setMaxResults JF&$t}
9I27TKy
(pageSize).list(); i9<pqQ
PaginationSupport ps = Q_-_^J
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new PaginationSupport(items, totalCount, pageSize, y$FW$Ka
ajR%c2G;
startIndex); IJYL s
return ps; J]lrS
} (.wIe/
}, true); x+ncc_2n&D
} _.IxRk)T
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public List findAllByCriteria(final (wIzat
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DetachedCriteria detachedCriteria){ >(uZtYM\j
return(List) getHibernateTemplate y&}E~5O
*4+3ObA
().execute(new HibernateCallback(){ x3jb%`o#!
publicObject doInHibernate %VYAd)gC
[[PEa-992
(Session session)throws HibernateException { poGc a1
Criteria criteria = IG)s^bP
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detachedCriteria.getExecutableCriteria(session); S#)Eom?V
return criteria.list(); *n"/a{6>
} UcBe'r}G
}, true); \PDd$syDA
} NI#X@
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public int getCountByCriteria(final +zXEYc
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DetachedCriteria detachedCriteria){ pyLRgD0
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Integer count = (Integer) d\x7Zw>
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getHibernateTemplate().execute(new HibernateCallback(){ 7K)6^r^
publicObject doInHibernate mxb(<9O
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(Session session)throws HibernateException { ~ P~
Criteria criteria = 0/S_e)U
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detachedCriteria.getExecutableCriteria(session); :RoBl3X=
return y_\p=0t8
(WJ${OW
criteria.setProjection(Projections.rowCount ?A(QyaKz
nKW*Y}VO
()).uniqueResult(); x77l~=P+!
} fP.F`V_Y
}, true); XGP6L 0j
return count.intValue(); ^Ge+~o?x
} j'9"cE5_
} i4^o59}8
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用户在web层构造查询条件detachedCriteria,和可选的 x| yEtO&
. e=C{
startIndex,调用业务bean的相应findByCriteria方法,返回一个 c478P=g=5
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PaginationSupport的实例ps。 v) vkn/:
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ps.getItems()得到已分页好的结果集 pdE3r$C
ps.getIndexes()得到分页索引的数组 ?LvCR_D:
ps.getTotalCount()得到总结果数 zZVfj:i8
ps.getStartIndex()当前分页索引 z dO#0tN
ps.getNextIndex()下一页索引 E<yW\
ps.getPreviousIndex()上一页索引 p.LFVFPT
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错
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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 ]Dw]p!@
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一下代码重构了。 X7s
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我把原本我的做法也提供出来供大家讨论吧: zbq@pj)Qu
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首先,为了实现分页查询,我封装了一个Page类: 27;ci:5
java代码: J~#;<e{\"
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/*Created on 2005-4-14*/ Fd0%lnui
package org.flyware.util.page; P*cNh43U
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/** s`0QA!G{-
* @author Joa ki85!k=Q2
* % LJs
*/ J>/w5$h5
publicclass Page { \Ym5<];E
x
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/** imply if the page has previous page */ ,_Z+8
privateboolean hasPrePage; j?MAED
By% =W5
/** imply if the page has next page */ ;<leKcvhQ&
privateboolean hasNextPage; Q=]w !I\
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M
/** the number of every page */ |+T1XYG5
privateint everyPage; ztw@Y|<2
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/** the total page number */ z<yU-m2h
privateint totalPage; q5?# 3 T=
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/** the number of current page */ ^k]XEW{PG
privateint currentPage; *hw\35%P`?
2 $Tj84'X
/** the begin index of the records by the current #5f-`~^C{
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query */ f"<O0Qw
privateint beginIndex; ;UxP
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/** The default constructor */ K"r*M.P>
public Page(){ 0(S"{Ov
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} &uO%_6J
x@*SEa
/** construct the page by everyPage -]QD|w3dp
* @param everyPage HaP}Y:p
* */ }2e??3
public Page(int everyPage){ ho$+L
this.everyPage = everyPage; m%76i;uP
} ~-I+9F
ll C#1
/** The whole constructor */ :53)Nv
public Page(boolean hasPrePage, boolean hasNextPage, _]Zs,Hy
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int everyPage, int totalPage, ,gS;m
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int currentPage, int beginIndex){ m&?#;J|B$
this.hasPrePage = hasPrePage; !1ED~3/X
this.hasNextPage = hasNextPage;
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this.everyPage = everyPage; CO`_^7o9(
this.totalPage = totalPage; 6b:tyQ
this.currentPage = currentPage; sJDas,7>
this.beginIndex = beginIndex; v-PXZ'7~
} {|'E
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/** \ioH\9
* @return `|/<\
* Returns the beginIndex. ^pYxKU_O
*/ 4y+< dw
publicint getBeginIndex(){ `5C,N!d8X
return beginIndex; og
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} Wr( y)D<y}
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/** D}mjN=Y
* @param beginIndex "OdXY"G
* The beginIndex to set. Dp':oJC
*/ HBMhtfWW
publicvoid setBeginIndex(int beginIndex){ \Rp-;.I@6
this.beginIndex = beginIndex; * cgI.+
} 9_
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/** lGOgN!?i
* @return Vb= Mg
* Returns the currentPage. Wh.?j>vB
*/ |b)Y#)C;
publicint getCurrentPage(){ tfGHea)M
return currentPage; !s&NT @ S
} yI"6Da6|y
1#ft#-g}
/** XR;eY:89
* @param currentPage eb =D/
* The currentPage to set. #':fkIYe'
*/ 7BJzMlJ1Y
publicvoid setCurrentPage(int currentPage){ QC9eUYe
this.currentPage = currentPage; fP(d8xTx2y
} }3OKC2K~
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/** s[w6FXt
* @return y$_eCmq
* Returns the everyPage. "\3B^ e,
*/ "t~
publicint getEveryPage(){ E/%9jDTQ
return everyPage; HxIIO[h
} Y9&,t\ q
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/** o
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* @param everyPage rv|)n>m
* The everyPage to set. ]{ntt}3G,
*/ P7{gfiB
publicvoid setEveryPage(int everyPage){ Uk6HQQ
this.everyPage = everyPage; x;8A!8w
} LyAn&h}
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/** Yo|,]X>/
* @return <c2'0I >
* Returns the hasNextPage. Z\k&gio5C^
*/ `pGa~!vl
publicboolean getHasNextPage(){ lx[oaCr
return hasNextPage; ,"HL~2:~
} ;N0~;I
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/** /K.!sQ$
* @param hasNextPage r(RKwr:m
* The hasNextPage to set. 6I4oi@hZz
*/ '2[albxSc
publicvoid setHasNextPage(boolean hasNextPage){ @
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this.hasNextPage = hasNextPage; n6BQk2l
} Y\$ySvZ0
s=0BMPDgm
/** XBp? w
* @return j'MO(ev
* Returns the hasPrePage. &3n~%$#N
*/ !X;1 }
publicboolean getHasPrePage(){ LdL/399<
return hasPrePage; Wwr;-Qa}g
} H*$jc\
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/** 6jC`8l:
* @param hasPrePage Bg|5KOnd
* The hasPrePage to set. Y07ZB'K
*/ iqe%=%ZR
publicvoid setHasPrePage(boolean hasPrePage){ V4KMOYqm
this.hasPrePage = hasPrePage; 4*Hgv:0?kI
} cT!\{~
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/** F*3j.lI
* @return Returns the totalPage. p(/dBt[3k
* JYW)uJ
*/ .K p
publicint getTotalPage(){ >8qQK r\"
return totalPage; @CZT
} 7r~~Y%=C|
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/** -T[lx\}
* @param totalPage [YUv7|\
* The totalPage to set.
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*/ 0a-0Y&lQm
publicvoid setTotalPage(int totalPage){ y"H*%]
this.totalPage = totalPage; /Z@tv.f
} t3&LO~Ye
*fn*h[pV&
} W8KDX_vGJ
d ysC4DS
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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 !3*(N8_|#
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个PageUtil,负责对Page对象进行构造: \ywXi~+kUv
java代码: f;x kT
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/*Created on 2005-4-14*/ h3z{(-~y
package org.flyware.util.page; urMG*7i <c
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import org.apache.commons.logging.Log; \4-"L>
import org.apache.commons.logging.LogFactory; zhpt%7So
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/** Q2F+?w;,
* @author Joa H\:lxR^
* q gLaa
*/ q(2K6
publicclass PageUtil { "6us#T
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privatestaticfinal Log logger = LogFactory.getLog |!"`MIw,
* Of4o
(PageUtil.class); OG~6L4"
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/** )`A3M)
* Use the origin page to create a new page 7,lq}a8z
* @param page hR
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* @param totalRecords fi$-;Gz
* @return F=a<~EpZ
*/ pnbIiyV
publicstatic Page createPage(Page page, int EodQ*{l
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totalRecords){ +E.GLn2/
return createPage(page.getEveryPage(), b+&%1C
+(1zH-^.
page.getCurrentPage(), totalRecords); D~$r\]av
} ~R2 6
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/** aW`Lec{.
* the basic page utils not including exception c;n *AK
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handler #~l(]h@
)
* @param everyPage !=:$lzS^
* @param currentPage +i2}/s@JJ
* @param totalRecords vDxe/x%
* @return page B9H@e#[
*/ 8'4S8DM
publicstatic Page createPage(int everyPage, int }` ! =
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currentPage, int totalRecords){ A?t%e
everyPage = getEveryPage(everyPage); x*nSHb
currentPage = getCurrentPage(currentPage); !qN||mCH
int beginIndex = getBeginIndex(everyPage, KjE+QUa
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currentPage); <c,u3cp
int totalPage = getTotalPage(everyPage, 0Pe>Es|^A#
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totalRecords); 9uBM<
boolean hasNextPage = hasNextPage(currentPage, fIwV\,s
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totalPage); Lg*B>=
boolean hasPrePage = hasPrePage(currentPage); CS=qj-(
}=8B*
returnnew Page(hasPrePage, hasNextPage, +[tE ^`-F
everyPage, totalPage, v>-VlQ
currentPage, CCWg{*og
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beginIndex); PX
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} AG?dGj^
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privatestaticint getEveryPage(int everyPage){ mA*AeP_$
return everyPage == 0 ? 10 : everyPage; m$W <
} .%Ta]!0
u(wGl_
privatestaticint getCurrentPage(int currentPage){ +{W>i; U
return currentPage == 0 ? 1 : currentPage; Xp8]qH|K
} TT4./R:
WeQk<y
privatestaticint getBeginIndex(int everyPage, int sh`s/JRf
B,@c;K
currentPage){ <p\6AnkMr
return(currentPage - 1) * everyPage; "Za>ZRR
} !>e5z|1
ghX|3lI\q
privatestaticint getTotalPage(int everyPage, int Y))u&*RuT0
r]l!WRn
totalRecords){ #&m0WI1
int totalPage = 0; $ n+w$CI)
-"h;uDz|z
if(totalRecords % everyPage == 0) E gal4
totalPage = totalRecords / everyPage; W'.s\e?gh
else bLQ ^fH4ww
totalPage = totalRecords / everyPage + 1 ; ?F6pEt4
&b?LP]
return totalPage; 'eJ+JM<0%
} %T)oCjM[\
i 4%xfN
privatestaticboolean hasPrePage(int currentPage){ u9}1)9
return currentPage == 1 ? false : true; @*Wh
} k7>|q"0C
E !a|Xp
privatestaticboolean hasNextPage(int currentPage, HKqwE=NZ
YE= q:Bv
int totalPage){ %ix)8+Eb
return currentPage == totalPage || totalPage == )~+ e`q
{e[c
0 ? false : true; Q`rF&)Q5
} IZ=Mlu
T.We: ,{
%c
[F;ug
} 5o6>T!
e#Z$o($t
H'LD}\K l
;Ww7"-=sw
p8\zG|b5
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 #ssN027
;Y;qg
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 W ]Nv33i
[
`X`2:@gQ
做法如下: *_KFW@bC:
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 +=mkCU
B?)@u|0
的信息,和一个结果集List: ']>Mp#j
java代码: nIoPC[%_
;+tpvnV;]
g*F '[Z."
/*Created on 2005-6-13*/ K\$J4~EtG
package com.adt.bo; ?APeR,"V
x)JOClLr
import java.util.List; #Ap;_XcKw
K"0PTWt
import org.flyware.util.page.Page; DZv=\<$,LF
h?f>X"*|(
/** T<L^N+<,{N
* @author Joa >^Yq|~[
*/ y8 KX<2s1
publicclass Result { }4{fQ`HT
~O]]N;>72"
private Page page; 5 gv/Pq &
x&`~R>5/
private List content; fnNYX]_bk
(C\hVy2X?N
/** N,f4*PQ
* The default constructor k~/>b~.c
*/ :gB[O>'<m
public Result(){ H{AMZyV0/d
super(); z OSs[[
} eh ,~F
(s1k$@d
/** =1u@7Bh
* The constructor using fields `$~RxzZ g
* :KKa4=5L
* @param page $rhgzpZ!X_
* @param content nD0}wiL{
*/ g1UGd
public Result(Page page, List content){ rx5B=M
this.page = page; 7-~Q5Kr.
this.content = content; s%!`kWVJ.
} R'dSbn
TP}h~8 /;
/** )$&dg2[
* @return Returns the content. iz~
pGkt
*/ F*Z=<]<+
publicList getContent(){ 2iU7 0(H
return content; NB7Y{)
w
} ^@"H1
>F@qpjoQE
/** =rd|0K"(r
* @return Returns the page. $v`afd y
*/ T?p`)
public Page getPage(){ a6h>=uT [
return page; 97,rE$bC
} KZbR3mi,
yfDAk46->6
/** 7JDN{!jT
* @param content 9ktEm|F3
* The content to set. 8*SP~q
*/ TS"D]Txs
public void setContent(List content){ n q19Q)
this.content = content; ,zQOZ'^
} ow/57P
^#):c`
/** K?4FT$9G
* @param page A;J MV+2N
* The page to set. @+Y8*Rj\3
*/ C*X
G_b ]
publicvoid setPage(Page page){ +y#T?!jQYj
this.page = page; 7yt=]1
} U{ ;l0 2S
} _ OaRY]
[Qdq}FYr
qUo-Dq>
{C^@Q"I
1P]de'-`j
2. 编写业务逻辑接口,并实现它(UserManager, r,N[ )@
.9|uQEL
UserManagerImpl) >J=<bhR
java代码: 'ZQWYr9R
CkRX>)=py
M]HgIL@9#
/*Created on 2005-7-15*/ (shK
package com.adt.service; -@IL"U6
pl V7+?G
import net.sf.hibernate.HibernateException; !7U\J]
m=b~i^@
import org.flyware.util.page.Page; cUK\x2
cgj.e
import com.adt.bo.Result; fA^7^0![
fj4^VXD
/** hxC!+ArVe
* @author Joa y1BgK>R
*/ yu
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publicinterface UserManager { qd!#t]
D22Lu;E
public Result listUser(Page page)throws E=/[s]@5
{5Eyr$
HibernateException; _1jw=5^P\i
Z,WW]Y,$
} 3SARr>HRyI
Y5-kj,CB
GJ}.\EaAJ
9DEh*%q
[BBpQN.^q6
java代码: /qxJgoa
[U_[</L7
4w{-'M.B
/*Created on 2005-7-15*/ 98*x 'Wp
package com.adt.service.impl; wq4nMY:#
00M`%c/
import java.util.List; 4^Ow^7N?
?En7_X{C?
import net.sf.hibernate.HibernateException; ^t78jfl
JJl7JwSTW
import org.flyware.util.page.Page; ):bu;3E
import org.flyware.util.page.PageUtil; JCQ:+eqt
lIuXo3
import com.adt.bo.Result; \>)f5 gV@
import com.adt.dao.UserDAO; M\yHUS6N
import com.adt.exception.ObjectNotFoundException; a{`"68
import com.adt.service.UserManager; j??tmo
iMWW%@U^=
/** ypA: P
* @author Joa GOW"o"S
*/ p`GWhI?
publicclass UserManagerImpl implements UserManager { ek[kq[U9
Igjr~@#
private UserDAO userDAO; Ky&KF0
>I-g[*
/** S\|^ULrH
* @param userDAO The userDAO to set. C6)R#
*/ a9[< ^
publicvoid setUserDAO(UserDAO userDAO){ ~JE|f 7
this.userDAO = userDAO; Bn-J_-%M
} +a]j[#
uMDtdC8
/* (non-Javadoc) *mV&K\_
* @see com.adt.service.UserManager#listUser SOH%Q_
d~<QAh#rG
(org.flyware.util.page.Page) ?
: md
*/ @xJCn}`Zj
public Result listUser(Page page)throws n{=7 yK
2 `5=0E1k
HibernateException, ObjectNotFoundException { n4>cERfa
int totalRecords = userDAO.getUserCount(); h]P/KVqR.
if(totalRecords == 0) S'?fJ.
throw new ObjectNotFoundException NQ!<f\m4n
J" bD\%
("userNotExist"); E{gv,cUM
page = PageUtil.createPage(page, totalRecords); ou;qO
5CT
List users = userDAO.getUserByPage(page); 6z1\a
returnnew Result(page, users); QSmJ`Bm
} `Z8^+AMc
0IFlEe[>#
} vpa fru4
lzoeST
ss;
5C:*y
P/`m3aSzX.
"!a`ygqpT
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 )]A9~H
M1(9A>|nF
询,接下来编写UserDAO的代码: 0h:G4
3. UserDAO 和 UserDAOImpl: iIB9j8
java代码: #7\b\~5
;[caiMA-
8{@`kyy|
/*Created on 2005-7-15*/ 8;8YA1@w
package com.adt.dao; wDZ
~B*~'I9b*
import java.util.List; fD(7FN8
.ujj:>
import org.flyware.util.page.Page; UnjNR[=
C1D !
V:
import net.sf.hibernate.HibernateException; ;24'f-Eri
-s89)lUkS
/** vu ?3$
* @author Joa QxA0I+i
*/ S" {GlRpd
publicinterface UserDAO extends BaseDAO { \2Xx%SX
Y.9~Bo<<r
publicList getUserByName(String name)throws !Z-9tYO
u/#&0_
P
HibernateException; Uf^RLdoDn
Lb^(E-
publicint getUserCount()throws HibernateException; jjX%$Hr
,{pGP#
publicList getUserByPage(Page page)throws -+' #*V
}
m6\C5
HibernateException; K@*rVor{
+Tp%5+E
} a(5y>HF
j,4,zA1j|
`>\4"`I
}<.7 xz|V
'X|v+?
java代码: mHHzCKE ,
s1Okoxh/!V
OFIMi^@
/*Created on 2005-7-15*/ %Dra7B%
package com.adt.dao.impl; n3*UgNg%fK
;n`
$+g:>
import java.util.List; pY,O_
t$
joY1(Y
import org.flyware.util.page.Page; e"PMvQ
Kc-Y
import net.sf.hibernate.HibernateException; Gxo#
!
import net.sf.hibernate.Query; n+X1AOE[L
fMyE}z
import com.adt.dao.UserDAO; |@+8]dy:l
;hkro$
/** zdqnL^wb
* @author Joa jjX'_E
*/ X:R%1+&*
public class UserDAOImpl extends BaseDAOHibernateImpl m,=)qex
.B6`OX&k
implements UserDAO { pK<%<dIc
,;7`{Nab
/* (non-Javadoc) L)1C'8).
* @see com.adt.dao.UserDAO#getUserByName W\'Nv/L
1Jl{1;c
(java.lang.String) 7F=2t_2O
*/ P&,hiGTDi
publicList getUserByName(String name)throws >/8ru*Oc
I'xC+nL@
HibernateException { /z..5r^,ZZ
String querySentence = "FROM user in class .r7D)xNa@
32s5-.{c/f
com.adt.po.User WHERE user.name=:name"; ZU)BJ!L,s
Query query = getSession().createQuery v3?kFd7%H~
xnT3^ #-h
(querySentence); " \`BPN
query.setParameter("name", name); W0C{~|e
return query.list(); HgYc@P*b
} @l)\?IEF@f
-g9^0V`G
/* (non-Javadoc) mMV2h|W
* @see com.adt.dao.UserDAO#getUserCount() dFx2>6AZt
*/ @X
K>
publicint getUserCount()throws HibernateException { N?\bBt@
int count = 0; E]\D>[0O
String querySentence = "SELECT count(*) FROM KlY,NSlQ
#NWZ k.S
user in class com.adt.po.User"; O>nK,.
Query query = getSession().createQuery BXNI(7xi
FwXKRZa
(querySentence); j p!
count = ((Integer)query.iterate().next *1\z^4=a]
1V-=$Q3
V7
()).intValue(); z~BD(FDI
return count; k& WS$R?u
} ]cn/(U`
Fq vQk
/* (non-Javadoc) t8t}7XD
* @see com.adt.dao.UserDAO#getUserByPage R:]/{b4Uq
gW'P`Oxw
(org.flyware.util.page.Page) KbXbT
*/ dFdlB`L
publicList getUserByPage(Page page)throws 6 #-6Bh)>4
oSN8Xn*qr
HibernateException { 8mk}nex
String querySentence = "FROM user in class 1P+Mv^%I
AQB1gzE
com.adt.po.User"; \m(ymp<c`
Query query = getSession().createQuery I/mvQxp
!'Pk
jP
(querySentence); VV?]U$
query.setFirstResult(page.getBeginIndex()) Y0 @'za^y
.setMaxResults(page.getEveryPage()); yJF 2
return query.list(); .Ln;m8
} `l+ >iM
FYp|oD2=1
} gsLr=
ov?.:M
"}0)YRz%
+R2^*
*<
\Y51KB\
至此,一个完整的分页程序完成。前台的只需要调用 I~d#p ]>
yB0jL:|a
userManager.listUser(page)即可得到一个Page对象和结果集对象 's$A+8;L
NE$VeW+@
的综合体,而传入的参数page对象则可以由前台传入,如果用 hq5NQi`
%
'9IP;
webwork,甚至可以直接在配置文件中指定。 zY]Bu-S3
n^* >a
下面给出一个webwork调用示例: @*CAn(@#N
java代码: ;[;)P tFz\
R#"U/8b>z
%T`4!:vy
/*Created on 2005-6-17*/ q:TZ=bs^
package com.adt.action.user; ]]\)=F`n77
.tZjdNE(h
import java.util.List; TrSN00
J!=](s5|
import org.apache.commons.logging.Log; !T<z'zZU
import org.apache.commons.logging.LogFactory; `
(7N^@
import org.flyware.util.page.Page; zWF
5m )-
)9;(>cdl
import com.adt.bo.Result; R2Twm!1
import com.adt.service.UserService; C>.]Bvg
import com.opensymphony.xwork.Action; Py|H?
, 6=
i0,%}{`
/** C_;HaQiu
* @author Joa <{$ev&bQ
*/ 2>!_B\%) H
publicclass ListUser implementsAction{ #g@
b}ySZlmy
privatestaticfinal Log logger = LogFactory.getLog cxtLy&C
hg%@ W
(ListUser.class); >{O[t2&
l@,); w=_P
private UserService userService; g0^~J2sDd
>Sc$R0
private Page page; mA&RN"+V
yf
`.%
privateList users; 3S[w'
xaGVu0q
/* T^/Gj|N*
* (non-Javadoc) xB?S#5G}
* JIyBhFI
* @see com.opensymphony.xwork.Action#execute() ddUjs8VvJ
*/ `U{o:
publicString execute()throwsException{ {toyQ)C7
Result result = userService.listUser(page); qR [}EX&3
page = result.getPage(); 8C*6Fjb#
users = result.getContent(); Ft3N#!ubl
return SUCCESS; i1b4 J
} 3R)cbwL
Eg@R[ ^T
/** =$"zqa.B6
* @return Returns the page.
|y{;|K
*/ ~[d=s
public Page getPage(){ '+o:,6
return page; /3)YWFZZc
} u~/M
}XfS#Xr1aV
/** GNhtnB
* @return Returns the users. g5kYyE
*/ 6.
+[
z
publicList getUsers(){ 2+T 8Y,g
return users; n:5O9,umZ
} ?=;e.qK=71
cCo07R
/** GW>7R6i
* @param page Gt\K Ln
* The page to set. W (=Wg|cr
*/ ]wkSAi5z*
publicvoid setPage(Page page){ "!%w9
this.page = page; XEf&Yd
} 5XSxQG@k^z
^D W#
/** /(hP7_]`2
* @param users nLFx/5sL
* The users to set. H6%!v1 u
*/ R,d70w
(_
publicvoid setUsers(List users){ %=NM_5a}]
this.users = users; ooLnJY#
} `}k&HRn
#a7Amh\nT
/** }#\;np
* @param userService E< zT
* The userService to set. v @$evmA
*/ 'f=) pc#&g
publicvoid setUserService(UserService userService){ `_ J^g&y~
this.userService = userService; b2/N H1A
}
:f?,]|]+-
} SQ~N X)
APHtJoS
+!L_E6pyXE
g:.,}L
1WUFk ?p
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, j,|1y5f
)AnlFO+V
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 zbIwH6
zJG x5JC
么只需要: (PsSE:r}+
java代码: RB lOTQjv
0_,3/EWa
!_XU^A>
<?xml version="1.0"?> \pewbu5^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork #FQm/Q<0
dVsAX(
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 4,w{rmj
0TuOY%+
1.0.dtd"> ctc`^#q
Z!*8JaMT
<xwork> G!e}j
@@
u'$yYzBE
<package name="user" extends="webwork- m]-v IUpb
}QWTPRn
interceptors"> RKoP6LGw
:{wsd$Qlj
<!-- The default interceptor stack name 0XQ".:+h
LRCS)UBY(.
--> zgq_0w~X
<default-interceptor-ref MUCJ/GF*
o/x5
name="myDefaultWebStack"/> wQdW
lon
!ulLGmUn
<action name="listUser" U>L=.\\|
Zeme`/aBb
class="com.adt.action.user.ListUser"> PBAz`y2
<param I7q?V1fu4
k[r./xEv+t
name="page.everyPage">10</param> !dbA (
<result +/@ZnE9s
RK~FT/
name="success">/user/user_list.jsp</result> shDt&_n
</action> HjUw[Yz+6
JR a*;_
</package> (}~eD
?G>5 D`V
</xwork> nIT ^'
Kc9mI>u H
4ye`;hXy
WnJLX ^;
I?> -
vYMbson}
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 6XOpB^@
zNsL^;uT
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。 G"U>fwFuK
2W"cTm
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 QN}3S0
+3o)L?:g
D25gg
{o5K?Pb
M[
~2,M&H
我写的一个用于分页的类,用了泛型了,hoho .~A"Wyu\
RZV1:hNN
java代码: 8Snq75Q<
)HzITsFZKT
ek{PA!9Sk
package com.intokr.util; 2,XqslB)
f<> YYeY
import java.util.List; Xg!|F[i
$vw}p.
/** ,a]~hNR*X
* 用于分页的类<br> g]iy-,e
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Y%CL@G60
* /[0 /8f6
* @version 0.01 u'~b<@wHB
* @author cheng >uPde5"ZF-
*/ ^zWO[$n}tP
public class Paginator<E> { /qkIoF2
privateint count = 0; // 总记录数 X,!OWz:[
privateint p = 1; // 页编号 sen{f^U
privateint num = 20; // 每页的记录数 ~gi( 1<#
privateList<E> results = null; // 结果 L$TKO,T
p\]LEP\z,
/** h4B#T'b
* 结果总数 TNFm7}=
*/ L$u&~"z-
publicint getCount(){ qT<qu(V:
return count; rCSG@D.
} <R~~yW:H
*Xtc`XH
publicvoid setCount(int count){ 0p>:rU~
this.count = count; 6B;_uIq5
} FvI0 J
dVmAMQk.g
/** <1g 1hqK3
* 本结果所在的页码,从1开始 E-U;8cOMv
* | 7'yk__m
* @return Returns the pageNo. ]g-qWSKU
*/ J|2Hqd
publicint getP(){ c7nk~K[6
return p; +} ! F(c
} z7Rcnr;
G4exk5
/** Znl>*e/|
* if(p<=0) p=1 q=0{E0@9({
* iJaNP%N
* @param p %}]4Nsd e
*/ i8[Y{a*
publicvoid setP(int p){ CTbhwY(/
if(p <= 0) Tk#&Ux{ZJ
p = 1; 1-]x
this.p = p; nhXp_Z9
} H'h4@S
=3v
1]7X
/** UVBw;V
* 每页记录数量 >/HU'
*/ /glnJ3
publicint getNum(){ U` nS` p
return num; |3T|F3uEX
} <#x%A0
uuK]<h*
/** d>"$^${
* if(num<1) num=1 _M]rH<h
*/ f_P+qm
publicvoid setNum(int num){ Oi%~8J>
if(num < 1) g d}TTe
num = 1; |8U7C\S[
this.num = num; Hv7D+j8M
} h, 6S$,UI
.'2gJ"?,
/** dR, NC-*
* 获得总页数 ZNC?Ntw
*/ e}O -I
publicint getPageNum(){ NF\^'W@N
return(count - 1) / num + 1; UE`4$^qs
} M>H^<N}'A
10I`AjF0
/** b;;Kxi:7$}
* 获得本页的开始编号,为 (p-1)*num+1 &{4Mo,x
*/ D%Jc?6/I#3
publicint getStart(){ J'^$|/Q
return(p - 1) * num + 1; 1>@|
} F-7b`cF9[r
KsU&<eQ
/** q>.t~
* @return Returns the results. TYS\:ZdXF
*/ HYYx*CJ)
publicList<E> getResults(){ bvu<IXX=2
return results; K8 4cE
} H6CGc0NS+
AFB 7s z
public void setResults(List<E> results){ ?NzeP?g
this.results = results; .L{+O6*c
} nIKT w
(kNTXhAr4
public String toString(){ M^Ay,jK!
StringBuilder buff = new StringBuilder 2l/5i]Tq
+?txGHQq
(); C\>Mt
buff.append("{"); 3k[<4-
buff.append("count:").append(count); -5_xI)i
buff.append(",p:").append(p); 2gR_1*|
buff.append(",nump:").append(num); +:Q/<^Z
buff.append(",results:").append 1;~ 1U9V
M j%|'dZz
(results); MG5Sn*(C
buff.append("}"); W]Tt8
return buff.toString(); v4a4*rBI"
} U
<$xp
|afK"N
} 7{6.
o-<_X&"a|5
M "P