Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 >~uKkQ_p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pZ 7KWk4
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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 [k=LX+w@
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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 UM. Se(kS
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分页支持类: >n5Kz]]%
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java代码: @XH@i+{B
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package com.javaeye.common.util; !{XVaQ?x
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import java.util.List; V""3#Tw
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publicclass PaginationSupport { G4"[ynlWV
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publicfinalstaticint PAGESIZE = 30; }5y]kn
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privateint pageSize = PAGESIZE; f4^\iZ{`G
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privateList items; 2MDY nMy
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privateint totalCount; $3(E0\#O
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privateint[] indexes = newint[0]; !D9V9p
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privateint startIndex = 0; ?8$h%Ov-
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public PaginationSupport(List items, int ^/7Y3n!|3
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totalCount){ ?YnB:z*eV
setPageSize(PAGESIZE); <#e!kWGR?
setTotalCount(totalCount); }?Tz=hP
setItems(items); =Ka :i>
setStartIndex(0); ^ ]SU (kY
} yu=(m~KX
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public PaginationSupport(List items, int %F] :nk`
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totalCount, int startIndex){ }z_7?dn/
setPageSize(PAGESIZE); nPjN\Es6
setTotalCount(totalCount); ,/..f!bp
setItems(items); vFsl]|<;8
setStartIndex(startIndex); '];=1loD
} HeM-
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public PaginationSupport(List items, int a`zw5
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totalCount, int pageSize, int startIndex){ G4)X~.Fy
setPageSize(pageSize); ` MXGEJF
setTotalCount(totalCount); C8
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setItems(items); /@]@Tz@'
setStartIndex(startIndex); CM+/.y T
} )5ISkbsxD
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publicList getItems(){ u$mp%d8
return items; cy#N(S[ 1
} q%k _C0
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publicvoid setItems(List items){ t`vIcCXqyl
this.items = items; };]f 3
} nh%Q";
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publicint getPageSize(){ Dhp|%_>
return pageSize; C07 U.nzh
} M7SVD[7~HM
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publicvoid setPageSize(int pageSize){ x|<89o
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this.pageSize = pageSize; [7gwJiK
} is}Y+^j.
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publicint getTotalCount(){ ?K^~(D8(
return totalCount; 73kL>u
} B;xGTl@8
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publicvoid setTotalCount(int totalCount){ [;hCwj#
if(totalCount > 0){ [5QbE$
this.totalCount = totalCount; o:Q.XWa@MG
int count = totalCount / JM Ikr9/$
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pageSize; Com`4>0>I
if(totalCount % pageSize > 0) U Zc%XZ`"V
count++; #Vh$u%q3
indexes = newint[count]; Z;nUS,?om
for(int i = 0; i < count; i++){ b#E!wMClS
indexes = pageSize * f3HleA&&
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i; bcC+af0L
} 3eP7vy
}else{ lM-*{<B
this.totalCount = 0; 6$6Qk !%
} u3@v
} 1rQKHC:|
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publicint[] getIndexes(){ j9/Ev]im|F
return indexes; 'ai!6[|SD
} ;m cu(J
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publicvoid setIndexes(int[] indexes){ ,7nA:0P
this.indexes = indexes; uw`fC%-xh
} H{nYZOf/
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publicint getStartIndex(){ @%sr#YqY
return startIndex; hpOUz%
} kw.IVz<
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publicvoid setStartIndex(int startIndex){ cPm-)/E)i
if(totalCount <= 0) N"wp2w
this.startIndex = 0; '4}c1F1T_
elseif(startIndex >= totalCount) &33.mdBH
this.startIndex = indexes s55t>t,g6
duk:: |{F
[indexes.length - 1]; s.7s:Q`
elseif(startIndex < 0) q=40l
this.startIndex = 0; X ?l F,p
else{ J%n{R60b
this.startIndex = indexes wu2C!gyBo
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[startIndex / pageSize]; `DPR >dd@
} U\\nSU
} ?dcR!-3
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publicint getNextIndex(){ AZTn!hrU
int nextIndex = getStartIndex() + ']]&<B}mz
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pageSize; \1p5$0z
if(nextIndex >= totalCount) 5h4E>LB.B
return getStartIndex(); 6b8@6;&LI
else \O7Vo<B&D
return nextIndex; t9Nu4yl
} 2m?!!Weq
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publicint getPreviousIndex(){ BOQeP/>
int previousIndex = getStartIndex() - <.h\%&'U
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pageSize; v 8`)h<:W?
if(previousIndex < 0) #Rkld v'
return0; @}e'(ju%R
else Bw[jrK
return previousIndex; K~# wvUb
} Yv`8{_8L
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} Gkr^uXNg#
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抽象业务类 ` tkd1M
java代码: /I'n]
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/** Jb~ -)n2
* Created on 2005-7-12 Ur626}
*/ ItTIU
package com.javaeye.common.business; =oF6|\]{;
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import java.io.Serializable; TgaDzF,j{A
import java.util.List; MGO.dRy_
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import org.hibernate.Criteria; tH:K6^oR
import org.hibernate.HibernateException; ndm19M8Y|
import org.hibernate.Session; 6Upg\(
import org.hibernate.criterion.DetachedCriteria; k"SmbFn%N0
import org.hibernate.criterion.Projections; $p4aNC
import ~^.&nph
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org.springframework.orm.hibernate3.HibernateCallback; \QUvImT
import &bJ98Nxl
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org.springframework.orm.hibernate3.support.HibernateDaoS KrkZv$u,
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upport; AEwb'
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import com.javaeye.common.util.PaginationSupport; ZW2#'$b
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public abstract class AbstractManager extends 2vnzB8"k
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HibernateDaoSupport { i&,U);T
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privateboolean cacheQueries = false; *:.0c
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privateString queryCacheRegion; Kc udWW]
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publicvoid setCacheQueries(boolean \| >eG u
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cacheQueries){ F.8{
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this.cacheQueries = cacheQueries; d L%E0o
} %,,h )9
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publicvoid setQueryCacheRegion(String
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queryCacheRegion){ 3R#<9O
this.queryCacheRegion = ^z&xy41#B
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queryCacheRegion; @?]-5 ~3;
} (+]k{
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publicvoid save(finalObject entity){ Aq'%a)Y2
getHibernateTemplate().save(entity); >!)VkDAG
} ^/n[5@6H
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publicvoid persist(finalObject entity){ @B9|{[P
getHibernateTemplate().save(entity); qfYb\b
} hTG
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publicvoid update(finalObject entity){ [S4\fy0
getHibernateTemplate().update(entity); <Ab:yD`K!
} w|nVK9.
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publicvoid delete(finalObject entity){ dY-a,ch"8p
getHibernateTemplate().delete(entity); R-Fi`#PG2
} E+1j3Q;
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publicObject load(finalClass entity, >rFvT>@NU
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finalSerializable id){ nIi_4=Z
return getHibernateTemplate().load 'j)eqoj
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(entity, id); R$@.{d&:w
} 3QHZC0AY
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publicObject get(finalClass entity, g^C6"rsnl
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finalSerializable id){ 5?fk;Q9+\
return getHibernateTemplate().get UA8!?r-cR
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(entity, id); m5p~>]}fYF
} QLUe{@ivc
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publicList findAll(finalClass entity){ PW`Tuj
return getHibernateTemplate().find("from aOD"z7}U
*@&
"MZ/M
" + entity.getName()); -0X> y
} []]3"n
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publicList findByNamedQuery(finalString l =yHx\
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namedQuery){ (Lo2fY5
return getHibernateTemplate u
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().findByNamedQuery(namedQuery); %yMzgk[u
} \$C4H
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publicList findByNamedQuery(finalString query, *e6|SZ &3
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finalObject parameter){ x]ti3?w
return getHibernateTemplate `"H?nf0
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().findByNamedQuery(query, parameter); h2%:;phH
} [j?<9
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publicList findByNamedQuery(finalString query, 4iz&"~&1
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finalObject[] parameters){ +_eb*Z`5o
return getHibernateTemplate \Wc/kY3&
gn"&/M9E
().findByNamedQuery(query, parameters); i'wF>EBz
} MI(i%$R-A
^I{]Um:
publicList find(finalString query){ :6?&FzD`
return getHibernateTemplate().find C):d9OI?
h`]/3Ma*:
(query); 2NknC>9(\
} > bF!Y]H
F?} *ovy
publicList find(finalString query, finalObject -mJ&N
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parameter){ p^rX.?X
return getHibernateTemplate().find " B{0-H+
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(query, parameter); X-$td~r
} k6L373e#Q
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public PaginationSupport findPageByCriteria %_MR.J+m2
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(final DetachedCriteria detachedCriteria){ &PuJV + y
return findPageByCriteria |/^aLj^u
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); KOEi_9i}
} e K1m(E.=
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public PaginationSupport findPageByCriteria DG*o
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(final DetachedCriteria detachedCriteria, finalint Qz) 8eIO:
Q(5:~**I
startIndex){ jfPJ5]Z
return findPageByCriteria &IEBZB\/+&
qV8\/7'A0a
(detachedCriteria, PaginationSupport.PAGESIZE, T0v@mXBQ
&@utAuI
startIndex); 8N*
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} #D/ }u./
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public PaginationSupport findPageByCriteria b/,!J]W
FR,#s^kF
(final DetachedCriteria detachedCriteria, finalint !BQ ELB$0
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pageSize, \v3>Eo[
finalint startIndex){ PtQ#
return(PaginationSupport)
_Kl{50}]
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getHibernateTemplate().execute(new HibernateCallback(){ O4d^ig-xaH
publicObject doInHibernate PP[)h,ZL*
5?{ >9j5
(Session session)throws HibernateException {
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Criteria criteria = JNM@Q
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detachedCriteria.getExecutableCriteria(session); 'x,GI\;?
int totalCount = .H(}[eG_
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((Integer) criteria.setProjection(Projections.rowCount 3@TG.)N4
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()).uniqueResult()).intValue(); a[P>SqT4`
criteria.setProjection ^,Y~M_=
1|~#028
(null); "Eok;io
List items = Avv
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criteria.setFirstResult(startIndex).setMaxResults M ,_^hm7
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(pageSize).list(); <7FP"YU
PaginationSupport ps = 3<)@ll
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new PaginationSupport(items, totalCount, pageSize, U8WHE=Kk\h
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startIndex); Yn$>QS 4
return ps; Mdlt zy=)L
} lN)Y
}, true); VO @
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} >Oi2gPA
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public List findAllByCriteria(final }/7.+yD
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DetachedCriteria detachedCriteria){ TRySl5jx@
return(List) getHibernateTemplate nv_m!JG7
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().execute(new HibernateCallback(){ mV**9-"
publicObject doInHibernate
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(Session session)throws HibernateException { j h1 bn
Criteria criteria = *@ <8&M9x
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detachedCriteria.getExecutableCriteria(session); RFZU}.*K$
return criteria.list(); _#J_$CE#
} cwM#X;FGq
}, true); "UhK]i*@l
} ;l/}Or2
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public int getCountByCriteria(final E'&OOEMN-
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DetachedCriteria detachedCriteria){ !7mvyc!'!
Integer count = (Integer) BGlGpl
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getHibernateTemplate().execute(new HibernateCallback(){ v2M"b?Q
publicObject doInHibernate e?^\r)1
PS_3Oq)
(Session session)throws HibernateException { ibZt2@GB)I
Criteria criteria = _S9rF-9G]
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detachedCriteria.getExecutableCriteria(session); ]^yV`Z8
return p|FlWR'mA
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criteria.setProjection(Projections.rowCount 8X}^~ e
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()).uniqueResult(); r,`Z.A
} ?
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}, true); a'
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return count.intValue(); u#a%(
} L?=#*4t
} 9]]!8_0=r
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用户在web层构造查询条件detachedCriteria,和可选的 nwa\Lrh
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Zw;$(="
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PaginationSupport的实例ps。 fkdf~Vb
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ps.getItems()得到已分页好的结果集 ?ada>"~GR_
ps.getIndexes()得到分页索引的数组 _v1bTg"?
ps.getTotalCount()得到总结果数 u/z,92mmS
ps.getStartIndex()当前分页索引 [MV`pF)x
ps.getNextIndex()下一页索引 +90u!r^v
ps.getPreviousIndex()上一页索引 9b?i
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 oUl=l}qnD
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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 Bj;\mUsk
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一下代码重构了。 1Z\(:ab13
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我把原本我的做法也提供出来供大家讨论吧: Z1VC5*K
A{4Dzm !
首先,为了实现分页查询,我封装了一个Page类:
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java代码: &foD&
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/*Created on 2005-4-14*/ +#0~:&!9
package org.flyware.util.page; H":/Ckok
%,33gZzf
/** 3}08RU7[!
* @author Joa @/9>=#4c
* 6hp{,8|D"m
*/ aPprMQ5
publicclass Page { Y
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Vre=%bGw
/** imply if the page has previous page */ l+t #"3
privateboolean hasPrePage; -&@]M>r@
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/** imply if the page has next page */ 9H>BWjS
privateboolean hasNextPage; A_@I_V$
p=2zS.
/** the number of every page */ BlL|s=dlQV
privateint everyPage; 3QIdN
e"*BHvy F
/** the total page number */ ,E%1Uq"
privateint totalPage; mU50pM~/i
C9o$9 l+B
/** the number of current page */ aQga3;S!
privateint currentPage; Hc M~
Sobtz}A*
/** the begin index of the records by the current L1rwIOgq^
k'g$2
query */ n"iNKR>nW
privateint beginIndex; F,Q?s9s
7 %3<~'v[
y86))
/** The default constructor */ TiQ^}5~M
public Page(){ s1{[{L3
<>]1Y$^Y
} <.}Ua(
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/** construct the page by everyPage
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* @param everyPage 6%E~p0)i%
* */ o*-9J2V=J
public Page(int everyPage){ %MbyKz:X
this.everyPage = everyPage; +>4^mE" \
} .A(i=!{q
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/** The whole constructor */ %&tb9_T)d
public Page(boolean hasPrePage, boolean hasNextPage, JD ]OIh
+TF8WZZF.d
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int everyPage, int totalPage, 5KJ%]B(H2
int currentPage, int beginIndex){ 8 aZ$5^z
this.hasPrePage = hasPrePage; FN!1|'VK
this.hasNextPage = hasNextPage; %l]Rh/VPn?
this.everyPage = everyPage; L7}i
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this.totalPage = totalPage; ;%WdvnW
this.currentPage = currentPage; vOe0}cR
this.beginIndex = beginIndex; g8l5.Mpx
} DT\ym9
C U$)QH{
/** 6{.J:S9n
* @return B6MkF"J<
* Returns the beginIndex. i4<BDX5
*/ O,|\"b1(
publicint getBeginIndex(){ s"coQ!e1.
return beginIndex; k;Hnu
} /zT`Y=1
n P1GW6Pu
/** _*E!gPO
* @param beginIndex K&dT(U
* The beginIndex to set. qjAh6Q/E`
*/ 9B=1Yr[
publicvoid setBeginIndex(int beginIndex){ ne*#+Q{E
this.beginIndex = beginIndex; mxp Y&Y
} j5^-.sEEw
qfrNi1\9-
/** xA #H0?a]
* @return .6m_>Y6
* Returns the currentPage. utH%y\NMF|
*/ /_*>d)
publicint getCurrentPage(){ 5)M2r!\
return currentPage; ~O03Sit-
} TzKK;(GX
$r79n-
/**
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* @param currentPage ,2,5Odrz
* The currentPage to set. 6(KmA-!b(O
*/ AVFjBybu9
publicvoid setCurrentPage(int currentPage){ JJnYOau
this.currentPage = currentPage; _kN*e:t
} mQr0sI,o]
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/** H~o <AmE0!
* @return :E'P7A
* Returns the everyPage. Fm3t'^SqF
*/ {rXs:N@
publicint getEveryPage(){
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return everyPage; 1mH\k5xu
} %e_"CS
&HDP!SLS
/** Fn+?u
* @param everyPage Ns=AjhLc z
* The everyPage to set. $$1qF"GF
*/ z-,VnhLx
publicvoid setEveryPage(int everyPage){ *e/K:k
this.everyPage = everyPage; b$-e\XB!
} xs!p|
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/** z$[C#5+2
* @return jd:B \%#![
* Returns the hasNextPage. = yXs?y"
*/ 0LL c 1t>}
publicboolean getHasNextPage(){ #YK5WTn5
return hasNextPage; rU2iy"L
} SEd5)0X^
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/** xf,5R9g/
* @param hasNextPage 76H!)={
* The hasNextPage to set. 0KvVw rWJ
*/ k6**u
publicvoid setHasNextPage(boolean hasNextPage){ lMifpK
this.hasNextPage = hasNextPage; %y<]Yzv.
} }Je>;{&%
]}PV"|#K{c
/** ]axh*J3`i
* @return N_DT7
* Returns the hasPrePage. q/gB<p9
*/ ]v 29 Rx
publicboolean getHasPrePage(){ w4:\N U
return hasPrePage; GWP dv
} BNucc']
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/** e@]Wh)
* @param hasPrePage & >JDPB?5
* The hasPrePage to set. Ru\_dr2yI}
*/ ;LwqTlJ*[L
publicvoid setHasPrePage(boolean hasPrePage){ V H^AcO
this.hasPrePage = hasPrePage; Bl;KOR
} b=[?b+
X% {'<baR
/** 53OJ-m%a
* @return Returns the totalPage. (ywo
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* f [o%hCS
*/ -9Ws=r0R
publicint getTotalPage(){ Q<"[C
1Lj
return totalPage; >cR)?P/o
} +M\8>/0oA
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/** nCxAQ|P?
* @param totalPage =y]$0nh
* The totalPage to set. SZ!=`a]
*/ gn1(4
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publicvoid setTotalPage(int totalPage){ #Gf+=G
this.totalPage = totalPage; M8;lLcgu.
} RDQ^dui
Iw=Sq8
} }IkQA#4$
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4FMF|U
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h
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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 +Ov2`O8?
GH4iuPh]
个PageUtil,负责对Page对象进行构造: 2y GOzc
java代码: `$5UHa2/
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/*Created on 2005-4-14*/ r.3KPiYK
package org.flyware.util.page; HK=[U9 o?
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import org.apache.commons.logging.Log; E+xuWdp.*
import org.apache.commons.logging.LogFactory; ]Yyia.B
&*,:1=p
/** Bx~[F
* @author Joa NYB[Zyp
* {U11^w1"3
*/ )M<vAUF
publicclass PageUtil { x8#ODuH
y&J@?Hc>
privatestaticfinal Log logger = LogFactory.getLog /X8<C=}
$.mQ7XDA9
(PageUtil.class); p9ZXbAJ{
aw $L$7b}
/** h5zVGr
* Use the origin page to create a new page .m4;^S2cO
* @param page C*70;:b
* @param totalRecords GUB`|is^
* @return {{yt*7k {
*/ ug&[ IL~lc
publicstatic Page createPage(Page page, int 3TuC+'`G
/\d$/~BFi
totalRecords){ f^Bc
return createPage(page.getEveryPage(), LJzH"K[Gg6
vP-M,4c
page.getCurrentPage(), totalRecords); 6vzk\n
} B/uniR^x
"dh:-x6
/** v6a]1B
* the basic page utils not including exception K`:=]Z8
` (4pu6uT
handler h rN%
* @param everyPage V~{
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* @param currentPage @Cq? :o<
* @param totalRecords xBnbF[
* @return page {y^3> 7
*/ @$@mqHI}
publicstatic Page createPage(int everyPage, int |I8Mk.Z=FA
"E!mva*NU
currentPage, int totalRecords){ B)SLG]72f
everyPage = getEveryPage(everyPage); eARk
QV
currentPage = getCurrentPage(currentPage); 1qdZc_x
int beginIndex = getBeginIndex(everyPage, $\Lyi#<
w2gf&Lc\
currentPage); ik1tidw
int totalPage = getTotalPage(everyPage, Xo5$X7m
qB6dFl\ (
totalRecords); '{?C{MK3Q
boolean hasNextPage = hasNextPage(currentPage, v@
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(g8*d^u#PO
totalPage); US&B!Q:v
boolean hasPrePage = hasPrePage(currentPage); yf1CXldi
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returnnew Page(hasPrePage, hasNextPage, D}mL7d1
everyPage, totalPage, `|e!Kq?#Q
currentPage, ~.tvrxg
0Dv JZ|e
beginIndex); ^y.UbI
} T8J4C=?/
TvhJVVQ+?
privatestaticint getEveryPage(int everyPage){ &vUq}r%P
return everyPage == 0 ? 10 : everyPage; 1hQN8!: <
} x!TZ0fq0
oh8L`=>&a
privatestaticint getCurrentPage(int currentPage){ T3J'fjY
return currentPage == 0 ? 1 : currentPage; _ *(bmJM
} @M;(K<%h
8^ep/ b&|
privatestaticint getBeginIndex(int everyPage, int EYzg%\HH
?H|T&66
currentPage){ I`B'1"{
return(currentPage - 1) * everyPage; (RL>Hn;.
} %|Qw9sbd
+a)E|(cN
privatestaticint getTotalPage(int everyPage, int 3Kq`<B~%
I2Ev~!
totalRecords){ Z|6{T
int totalPage = 0; _2Zp1h,
sa-9$},z4
if(totalRecords % everyPage == 0) ^QL 877
totalPage = totalRecords / everyPage; x1[?5n6
else x"B'zP
totalPage = totalRecords / everyPage + 1 ; ? 5|/
C
.(Y6$[#@
return totalPage;
'ig, ATY
} lu\o`m5wF
=7/-i
privatestaticboolean hasPrePage(int currentPage){ y;`eDS'0.N
return currentPage == 1 ? false : true; W
Ox_y,
} PXYE;*d(
a:!uORQby
privatestaticboolean hasNextPage(int currentPage, !p.^ITM3S
M@7Xp)S"
int totalPage){ [~%`N*G
return currentPage == totalPage || totalPage == &y.dmW
6SEltm(
0 ? false : true; H#(<-)j0_
} wq0aF"k
T 1Cs>#)
:=. *I
} KFhG (
`lCuU~~ag
g`Md80*Zfk
}[=YU%[o:
%$X\"
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 .]t5q%}j
&9 B_/m3
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 2<6j1D^jM
ZwJciT!_~
做法如下: MOZu.NmO
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 o:\XRPB
([pSVOnIz
的信息,和一个结果集List: `iYc<N`
java代码: h7W}OF_=y
GW
m4~]0E
;h=S7M9.
/*Created on 2005-6-13*/ &?<AwtNN
package com.adt.bo; Ye|G44z
aqL<v94wX
import java.util.List; )x\z@g
UxqWnHH.`
import org.flyware.util.page.Page; Y3oMh,
UKs$W`
/** r*d Q5
_
* @author Joa xZ ;bMxZ
*/ Bw-s6MS
publicclass Result { ^ KOzCLC
'p)QyL`d
private Page page; xrI}3T
l9Pu&M?5
private List content; SaNN;X0
ua#K>sur.
/** OmNn,PCl8
* The default constructor a<p
%hY3
*/ ~CFMIQ et
public Result(){ WOb8"*OM
super(); w2Kq(^?
} {3 o%d:
AU`OESSI
/** 6ZgNHARS
* The constructor using fields EXHR(t}e
* ~d+O/:=K_
* @param page f\'G`4e
* @param content J|?[.h7tO
*/ B1,?{Ur
public Result(Page page, List content){ k~|ZO/X@l%
this.page = page; 1ypjyu
this.content = content; }200g_^
} DpNX66O
lk o3]A3
/** [x$;XqA
* @return Returns the content. L8Dm9}
*/ i-"<[*ePd
publicList getContent(){ s((b"{fFb
return content; wRi~Yb?
} kPedX
PL!tk^;6-
/** I1v@\Rb
* @return Returns the page. H<z30r/-w
*/ dcP88!#5-
public Page getPage(){ 0STk)>3$-
return page; !p"Kd ~
} C=s((q*
~D_rZ&
/** C\/b~HU
* @param content }Fz!6F2w
* The content to set. *V<)p%l.
*/ 1sMV`qv>
public void setContent(List content){ s)Gb!-``
this.content = content; u{pTva
} F*.
/D~K
IY~
{)X
/** fGG
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* @param page CP@o,v-
* The page to set. v$Dh.y
*/ I,w^?o
publicvoid setPage(Page page){ E4hq}
this.page = page; ,A^L=+
} 7Z
VVR*n|
} ~V!EtZG$
EI<"DB
Y0rf9
v F]
D`8E-Bq
2. 编写业务逻辑接口,并实现它(UserManager, 0NVG"-Q
8R&z3k;!t
UserManagerImpl) l(.7t'
java代码: ]}5`7
$`ON!,oa
y B1W>s8&
/*Created on 2005-7-15*/ Qz'O{f
package com.adt.service; HH+TjX/b
YHJ'
import net.sf.hibernate.HibernateException; h)"'YzCt
oJhEHx[f
import org.flyware.util.page.Page; [;)~nPjI
kWI]fZ_n
import com.adt.bo.Result; CzK%x?~]
UzXDi#Ky
/** M_yZR^;^-
* @author Joa >3v0yh_3
*/ W=q?tD~V
publicinterface UserManager { 7'c8]/qh
&mCs%l
public Result listUser(Page page)throws ^.nwc#
(L]T*03#
HibernateException; o,iS&U"TC
^XtHF|%0T
} 9t,aT!f
Z?vY3)
:k Rv
O<gP)ZW~
tW'qO:y+
java代码: e,PQ)1
[RroHXdk+
*C,$W\6sz
/*Created on 2005-7-15*/ K+(m'3`
package com.adt.service.impl; g`y/_
LX&=uv%-^
import java.util.List; Lqy|DJ%
x'VeL|
import net.sf.hibernate.HibernateException; 5<0Yh#_
18l~4"|fk
import org.flyware.util.page.Page; H{p[Ghp
import org.flyware.util.page.PageUtil; cx,u2~43A&
(cbB%
import com.adt.bo.Result; #l8K8GLuf
import com.adt.dao.UserDAO; b@UF
PE5jy
import com.adt.exception.ObjectNotFoundException; 7!]k#|u
import com.adt.service.UserManager; ^/4{\3
B$iMU?B3
/** \H}@-*z+)
* @author Joa ~8S4Kj)%
*/ >-o?S O(M,
publicclass UserManagerImpl implements UserManager { KV3+}k
qX}dbuDE"P
private UserDAO userDAO; i1kh@s~8UC
CVn;RF6
/** 4.$hHFqS^5
* @param userDAO The userDAO to set. 5wVi{P5+
*/ p)AvG;
publicvoid setUserDAO(UserDAO userDAO){ Q'vIeG"o
this.userDAO = userDAO; o
F,R@f
} crF9,p
[K^q:3R
/* (non-Javadoc) 8I|1Pl
* @see com.adt.service.UserManager#listUser _'o^@v:
J^e|"0d
(org.flyware.util.page.Page) `^@g2c+d
*/ pRa oR
public Result listUser(Page page)throws 8wNU2yH+D
M 2U@gC|{
HibernateException, ObjectNotFoundException { (,Zz&3
AV
int totalRecords = userDAO.getUserCount(); }tg:DG
if(totalRecords == 0) +RKE|*y
throw new ObjectNotFoundException (*@~HF,t=
$T@xnZ
("userNotExist"); _<&K]e@dp
page = PageUtil.createPage(page, totalRecords); -t706(#k
List users = userDAO.getUserByPage(page); ~P.-3
returnnew Result(page, users); b&_u
O
} ;#Bh_f
=FC;d[U
} /m|&nl8"qe
f1,$<Y|qU
WG!;,~f>o
gx{~5&1
kkuQ"^<J
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w[n>4?"{
#+5mpDh
询,接下来编写UserDAO的代码: z ]4g`K+
3. UserDAO 和 UserDAOImpl: 8Nl|\3nl-
java代码: M#gGD-
Jb-QP'$@
xWI 0s;k
/*Created on 2005-7-15*/ %0M^
package com.adt.dao; eDMwY$J
dJ"xW;"
import java.util.List; (YWc%f4
8=_| qy}l/
import org.flyware.util.page.Page; I3y4O^?
I4DlEX
import net.sf.hibernate.HibernateException; GeW$lA I
9/qS*Zdh)
/** l+kg4y
* @author Joa {w1h<;MH
*/ Q)i`.mHfFI
publicinterface UserDAO extends BaseDAO { }(7QJk5 j
2/o/UfYjgF
publicList getUserByName(String name)throws af5`ktx
NGeeD?2~
HibernateException; Hbj:CViYq
HC`3AQ12!&
publicint getUserCount()throws HibernateException; ZN]c>w[
)I
^+l\YB7pD
publicList getUserByPage(Page page)throws VX@G}3Ck
|ssIUJ
HibernateException; UE;)mZ=l|
= 8e8!8
} WHk/mAI-s
j24
%Yn)t3d
.7^-*HT}
!rqR]nd
java代码: Q]'!FmXf
<UL|%9=~
e9~4wt
/*Created on 2005-7-15*/ zjZTar1Re
package com.adt.dao.impl; )CTM
:|mkI#P.
import java.util.List; /'_ RI
9{#|sABGD
import org.flyware.util.page.Page; "8
mulE,
%4KJ&R
(>[
import net.sf.hibernate.HibernateException; qiryC7.E
import net.sf.hibernate.Query; dct#ECT
aM}"DY-_
h
import com.adt.dao.UserDAO; y5D?Bg|M
Oo .Qz
/** vaZZzv{H
* @author Joa A>2p/iMc
*/ zQ+t@;g1
public class UserDAOImpl extends BaseDAOHibernateImpl F}DD;K
~8{3Fc 0
implements UserDAO { ck+rOGv7{Z
0l@+xS;
/* (non-Javadoc) GK%ovK
* @see com.adt.dao.UserDAO#getUserByName jP'b! 4
rB?cm]G=
(java.lang.String) "uC*B4`
*/ 1y;zPJ<ntm
publicList getUserByName(String name)throws I,3!uogn
OFbg]{ub?
HibernateException { 3:#rFb
String querySentence = "FROM user in class B'/ >Ax&
_q4m7C<
com.adt.po.User WHERE user.name=:name"; c/U6K
yiK
Query query = getSession().createQuery +N@F,3yNa
!l^AKn|
(querySentence); ybO,~TQ
query.setParameter("name", name); *b_54X%3
return query.list(); ~]M"
} .x8$PXjPG
7# 3)&"j
/* (non-Javadoc) fC|u
* @see com.adt.dao.UserDAO#getUserCount() ~ }22 Dvo
*/ aB'@8[]z
publicint getUserCount()throws HibernateException { #Q7$I.O]
int count = 0; gAP}KR#T
String querySentence = "SELECT count(*) FROM Ti'kn{
Zv
Uk6!Sb
user in class com.adt.po.User"; j56 An6g
Query query = getSession().createQuery 7k|(5P;
w'XgW0j{
(querySentence); v{Vesf
count = ((Integer)query.iterate().next }}1Q<puM
q:^Cw8
()).intValue(); ,[L$
return count; R2W_/fsG
} o+TZUMm
Z+(V \
/* (non-Javadoc) &J:)*EjVl5
* @see com.adt.dao.UserDAO#getUserByPage S I5QdX
p04+"
(org.flyware.util.page.Page) DA~ELje^j
*/ /vu!5?S
publicList getUserByPage(Page page)throws F JhVbAMd
GR
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HibernateException { RC%r7K f
String querySentence = "FROM user in class 'O9=*L)X
H>6;I
com.adt.po.User"; 0B/a$NC
Query query = getSession().createQuery or`stBx
*pp1Wa7O
(querySentence); yfQE8v+
query.setFirstResult(page.getBeginIndex()) q(^J7M)
.setMaxResults(page.getEveryPage()); GJPZ[bo
return query.list(); BwD1}1jp
} D7/Bp4I#o
Ypj)6d
} c@M@t0WT[
_B FX5ifK
vI}S6-"<
_1Gut"!{\
QPE.b-S
至此,一个完整的分页程序完成。前台的只需要调用 |LH*)GrD*t
! -@!u
userManager.listUser(page)即可得到一个Page对象和结果集对象 ZH_4'm!^g|
mkzk$_
的综合体,而传入的参数page对象则可以由前台传入,如果用 a@ }r[0O
q.{/{9
webwork,甚至可以直接在配置文件中指定。 ][#*h`I
2tm-:CPG
下面给出一个webwork调用示例: LfXr(2u
java代码: vK`h;
Qp&ySU8
w{EU9C
/*Created on 2005-6-17*/ q|l|mO
package com.adt.action.user; ?^4sE-C6
PGl-2Cr
import java.util.List; 6 <S&~q
=2)t1 H
import org.apache.commons.logging.Log; ^T6!z^g1h
import org.apache.commons.logging.LogFactory; Kg-X]yu*0
import org.flyware.util.page.Page; g@VndAp
rss.F3dK
import com.adt.bo.Result; z}2e;d 7
import com.adt.service.UserService; cY'To<v
import com.opensymphony.xwork.Action; ~9YA!48
y@\Q@
9
/** Er1u1@
* @author Joa b7sE
*/ g~:(EO(w
publicclass ListUser implementsAction{ qpqz. {\
UZXcKl>u
privatestaticfinal Log logger = LogFactory.getLog ruA+1-<f
<;E[)tv
(ListUser.class); ,Ysl$^\
}Rxg E~F
private UserService userService; ?iEXFYJG
G_N-}J>EP
private Page page; q }v04Yy,o
[*{\R`M
privateList users; |$?Ux,(6
\"`>-v"h
/* X+E\]X2
* (non-Javadoc) 39aCwhh7v
*
|iUfM3
* @see com.opensymphony.xwork.Action#execute() >dvWa-rNUT
*/ mQ60@_"Y=,
publicString execute()throwsException{ eGe[sv"k
Result result = userService.listUser(page); Y!1^@;)^
page = result.getPage(); '}pgUh_
users = result.getContent(); 3s_k>cO=
return SUCCESS; )cqDvH
} nB@iQxcz
H@2"ove-uC
/** .4C[D{4
* @return Returns the page. M?~<w)L}
*/ eMl]td rI
public Page getPage(){ +>WC^s
return page; 7?!Z+r
} Q^MXiEO+
xV>iL(?
/** PVD ~W)0m*
* @return Returns the users. *L;pc g8{
*/ !&a;P,_Fb
publicList getUsers(){ }6CXJ+-UR
return users; l4mUx`!
} ;]&~D
+XH
.mT#%ex
/** $\,BpZ
}3
* @param page 5&?KW)6 Rz
* The page to set. j
FPU
zB"
*/ X<Th{kM2
publicvoid setPage(Page page){ ,5\2C{
this.page = page; Q$3\ /mz
} LmXF`Y$
=CjNtD2]
/** bCA2ik
* @param users YA"Ti9-EV
* The users to set. 97(Xu=tX
*/ 8R\>FNk;
publicvoid setUsers(List users){ '_.q_Tf-^
this.users = users; <Qcex3
} #*Yi4Cn<
?E+:]j_
/** cebs.sF:
* @param userService 7b&JX'`Mb
* The userService to set. 't|Un G
*/ TvunjTpaj
publicvoid setUserService(UserService userService){ j{{~Z M
this.userService = userService; PTbA1.B
} ~!]&>n;=G
} b^[W_y
RgB6:f,
?$|uT
jl.okWuiY
E0"10Qbi
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, aho'|%y)
0?lp/|K
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 pk-yj~F }
-}{%Q?rYj
么只需要: vKNt$]pm=
java代码: =\~E n5
r]A"Og_U
p?+lAbe6H
<?xml version="1.0"?> .:}.b"%m
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]y3pE}R
]\CU9J|H8
1.0//EN" "http://www.opensymphony.com/xwork/xwork-
<^lJr82
[YC=d1F5
1.0.dtd"> I
jZ]_*^!
-1qZqU$h
<xwork> ;mDM5.iF
&|v{#,ymeb
<package name="user" extends="webwork- 3gb|x?
?h/xAl
interceptors"> CF]i}xpWV
kf<c,3A
<!-- The default interceptor stack name exfmq
hf;S]8|F
-->
}10\K
<default-interceptor-ref ;W]D ~X&
L2KG0i`+
name="myDefaultWebStack"/> "r
u]?{v
o4$Ott%Wm
<action name="listUser" U1OFDXHG
l^.K'Q1~a
class="com.adt.action.user.ListUser"> vt//)*(.$
<param XMGx^mn
(=1)y'.
name="page.everyPage">10</param> {@?G 9UypA
<result /D]Kkm)
4t04}vp
name="success">/user/user_list.jsp</result> ?AEd(_a!q
</action> a Sf/4\
c! @F
</package> /D<"wF }@J
g& k58{e
</xwork> *l{yW"Su
r!7 Y'|
n|Pr/ddL
Y$g}XN*)E
9:5:`'b
l[ne/O
JJ
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 'n0 .#E_
P"1 S$oc
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。 TI=h_%mO
b;#\~(a
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 cq*=|m0}Z
. V$ps-t
rz%<AF Z
%K(0 W8&
nBN&.+3t
我写的一个用于分页的类,用了泛型了,hoho 9AHSs,.t
-I":Z2.fR
java代码: . w H*sb
Tv5g`/e=Ej
GMW,*if8p
package com.intokr.util; HRB[GP+
'7*=`q{
import java.util.List; M\oTZ@
I;7nb4]AmF
/** {fV}gR2
* 用于分页的类<br> fr[3:2g-_
* 可以用于传递查询的结果也可以用于传送查询的参数<br> WZZ4]cC
* )zq.4
* @version 0.01 #?[.JD51l
* @author cheng JN'cXZJPn
*/ :!fG; )=
public class Paginator<E> { g>
S*<
privateint count = 0; // 总记录数 >^$2f&z
privateint p = 1; // 页编号 "&~
0T#
privateint num = 20; // 每页的记录数 p'n4)I2#
privateList<E> results = null; // 结果 nmFC%p)4
}P9Ap3?
/** VR5fqf|*
* 结果总数 g~S)aU\:,
*/ [zkikZy
publicint getCount(){ hWo=;#B*
return count; DJ@|QQ
} is?2DcSl5
xJZ@DR,#
publicvoid setCount(int count){ 7=XL!:P
this.count = count; }_
mT
l@*
} ?!VIS>C(
a j\nrD1
/** aqU'
T
* 本结果所在的页码,从1开始 N_Akmh0D
* ? 1*m,;Z
* @return Returns the pageNo. wsU V;S*X%
*/ B>y9fI
publicint getP(){ $ (=~r`O+1
return p; o4b~4h{%
} s;flzp8
CjIu[S1%
/** fV:4#j
* if(p<=0) p=1 qT:zEt5
* clw%B
* @param p 'b*%ixa
*/ '3IC*o"
publicvoid setP(int p){ -62'}%?A<C
if(p <= 0) ;a{ :%t
p = 1; llV3ka^!
this.p = p; 41a.#o
} <"D=6jqZ
!QI\Fz?
/** =qy=-j]
* 每页记录数量 ?E%ELs_Dl
*/ ENF"c$R
publicint getNum(){ {gNV[45
return num; JO<wK
} u]+~VT1C,3
73#x|lY
/** %?^6).aEK
* if(num<1) num=1 h:zK(;
*/ ,j:|w+l
publicvoid setNum(int num){ p!O(Y6QM
if(num < 1) ,#d? _?/:O
num = 1; $D
v\
e
this.num = num; Ch$*Gm19Z
}
c gzwx
Ofm%:}LV
/** mbnV[
* 获得总页数 lv vs%@b>
*/ ;,i]w"*
publicint getPageNum(){ @' ;B_iQ
return(count - 1) / num + 1; T,xPSN2A*
} kr$b^"Ku
PHA-9\jC{
/** c|F[.;cR
* 获得本页的开始编号,为 (p-1)*num+1 8]4U`\k4
*/ 8Og_W8
publicint getStart(){ [aI]y=v
return(p - 1) * num + 1; U9D!GKVp
} ?bM_q_5
N]KxAttt
/** DvvT?K
* @return Returns the results. s Y?,0T_m
*/ bAKiq}xG%i
publicList<E> getResults(){ OHiQ7#y
return results; \U|ZR
} kJWN.
=+t^ f
public void setResults(List<E> results){ n,B,"\fw
this.results = results; s
w39\urf
} T3`ludm^u
kP/M<X"
public String toString(){ /mp*>sNr6
StringBuilder buff = new StringBuilder cZ)}LX
1hcjSO
(); lA>DS#_
buff.append("{"); /-#I_>:8'
buff.append("count:").append(count); uV 7BK+[O
buff.append(",p:").append(p); }$bF
5&
buff.append(",nump:").append(num); A:7k+4
buff.append(",results:").append pABs!A`N
G7N|
:YK
(results); R(n^)^?
buff.append("}"); 5]M>8ll
return buff.toString(); o.q/O)'V u
} [HCAmnb
pv&y91
} .BFYY13H
1Bpv"67
LBF 1;zjK