Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 =1`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 J]fjg%C2m
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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 Fc 5g~T
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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 .hETqE` E
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分页支持类:
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java代码: urXM}^
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package com.javaeye.common.util; 2\EMtR>.M'
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import java.util.List; X}
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publicclass PaginationSupport { qC`"<R=GX
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publicfinalstaticint PAGESIZE = 30; )oHIRsr
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privateint pageSize = PAGESIZE; %<I0-o
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privateList items; 9I^_n+E
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privateint totalCount; aViJ?*
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privateint[] indexes = newint[0]; "6Ly?'HK
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privateint startIndex = 0; ~mmI]
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public PaginationSupport(List items, int =2->1<!x6<
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totalCount){ .+{nfmc,c
setPageSize(PAGESIZE); F
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setTotalCount(totalCount); $ZwsTV]x
setItems(items); f,`FbT
setStartIndex(0); dtm_~r7~
} kwZC3p\\
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public PaginationSupport(List items, int IExQ}I
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totalCount, int startIndex){ KJcdX9x
setPageSize(PAGESIZE); HHa7Kh|-H
setTotalCount(totalCount); ,|xG2G6
setItems(items); )p12SGR5
setStartIndex(startIndex); <(#cPV@j
} -[Zau$;J<
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public PaginationSupport(List items, int OXA_E/F
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totalCount, int pageSize, int startIndex){ <Hm:#<\
setPageSize(pageSize); +S0A`rL
setTotalCount(totalCount); "LXLUa03
setItems(items); MeP U`M--
setStartIndex(startIndex); >G/>:wwSP.
} 2tn%/gf'm
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publicList getItems(){ l_^>spF
return items; 7fnKe2MM
} K2:r7f
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publicvoid setItems(List items){ +=u*!6S
this.items = items; PX2Ejrwj
} z?1GJ8
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publicint getPageSize(){ =p&6A^
return pageSize; Q
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} \mWXr*;
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publicvoid setPageSize(int pageSize){ YF&SH)Y7
this.pageSize = pageSize; <uv{/L
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} y^M'&@F
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publicint getTotalCount(){ *;"^b\f5_
return totalCount; !4.;Ftgjn
} Wc`Vcn1
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publicvoid setTotalCount(int totalCount){ uz'beE
if(totalCount > 0){ NS b<
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this.totalCount = totalCount; 5:n&G[Md
int count = totalCount / mpr["C"l
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pageSize; _;LHC;,:
if(totalCount % pageSize > 0) Ux zwgVT
count++; ;F~GKn;}
indexes = newint[count]; C .YtjLQP$
for(int i = 0; i < count; i++){ /_jApZz
indexes = pageSize * ;]nU->
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i; Ej.D!@
} %$sWNn
}else{ wJ IJPYTK
this.totalCount = 0; *jA%.F
} r% mN]?u
} /!AdX0dx
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publicint[] getIndexes(){ ?kS5=&<
return indexes; k"Sw,"e>+
} xZ9y*Gv\=
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publicvoid setIndexes(int[] indexes){ BAt2m-
this.indexes = indexes; j&8 ~X2?*
} If4YqBG
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publicint getStartIndex(){ :B=`^>RK
return startIndex; Zjo9c{\
} UI;!_C_
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publicvoid setStartIndex(int startIndex){ =1+I<Ljk
if(totalCount <= 0) %FyB\IQ
this.startIndex = 0; K90Zf
elseif(startIndex >= totalCount) {nHy!{+qqG
this.startIndex = indexes "aa6W
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[indexes.length - 1]; 53(m9YLk
elseif(startIndex < 0) eMh:T@SN
this.startIndex = 0; s0nihX1Z-
else{ %LVk%kz
this.startIndex = indexes Hs-NP#I
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[startIndex / pageSize]; Tmw
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} &"^A
} <F=j6U7
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publicint getNextIndex(){ qt;6CzL
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int nextIndex = getStartIndex() + /n"A%6S
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pageSize; `_v-Y`Z
if(nextIndex >= totalCount) "[#jq5>
:
return getStartIndex(); aMz%H|/$
else ZFdQZ=.'
return nextIndex; ]j{S' cz
} {b#c0>.8-
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publicint getPreviousIndex(){ &`@Jy|N\
int previousIndex = getStartIndex() - -rH3rKtf~
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pageSize; a)Wf* <B
if(previousIndex < 0) B8TI 5mZ4
return0; h hdn9n
else k|
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return previousIndex; r/{VL3}F_e
} nFB;! r
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} ?Z14l0iZ%d
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抽象业务类 atN`w=6A`
java代码: ;yUY|o
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/** ^SjGNg^ 7D
* Created on 2005-7-12 zg5u
*/ UW>~C
package com.javaeye.common.business; cAiIbh>c
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import java.io.Serializable; =)bZSb"<"
import java.util.List; =1esUO[nx
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import org.hibernate.Criteria; +HfjnEbtBs
import org.hibernate.HibernateException; DD-DY&2R
import org.hibernate.Session; 7'&Xg_
import org.hibernate.criterion.DetachedCriteria; Ne#nSx5,
import org.hibernate.criterion.Projections; h{h=',o1
import I{RktO;1
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org.springframework.orm.hibernate3.HibernateCallback; .<j8>1
import @L~y%#
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org.springframework.orm.hibernate3.support.HibernateDaoS w6E?TI
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upport; oF*Y$OEu?c
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import com.javaeye.common.util.PaginationSupport; k5ZwGJ#r
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public abstract class AbstractManager extends Lc.7:r
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HibernateDaoSupport { "qDEI}
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privateboolean cacheQueries = false; Nh+$'6yT%
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privateString queryCacheRegion; a
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publicvoid setCacheQueries(boolean 9u)h$VC
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cacheQueries){ o?X\,}-s
this.cacheQueries = cacheQueries; 6#K_Rg>.
} 7v?Ygtv
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publicvoid setQueryCacheRegion(String bX9}G#+U
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queryCacheRegion){ F0|T%!FB>%
this.queryCacheRegion = xp39TiXJ*
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queryCacheRegion; b"zq3$6*
}
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publicvoid save(finalObject entity){ gr7W&2x7\
getHibernateTemplate().save(entity); T|}HK]QOX
} ; w+A38N$J
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publicvoid persist(finalObject entity){ Z$pR_dazU
getHibernateTemplate().save(entity); 0\mM^+fO
} ~pw_*AN
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publicvoid update(finalObject entity){ "2;UXX-H
getHibernateTemplate().update(entity); 4dy)g)wM
} ^]v}AEcmW
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publicvoid delete(finalObject entity){ dk.da&P
getHibernateTemplate().delete(entity); eHjR/MMr_
} Y6CadC
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publicObject load(finalClass entity, nyDqR#t
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finalSerializable id){ +I/P5OGRN
return getHibernateTemplate().load ngNg1zV/q
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(entity, id); ]]]7"a
} Cf+O7Y`^
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publicObject get(finalClass entity, 2f-Z\3)9 J
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finalSerializable id){ jQ[Z*^"}
return getHibernateTemplate().get ))MP]j9
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(entity, id); rKjQEO$yi
} AUN Tc3
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publicList findAll(finalClass entity){ qNvKlwR9;k
return getHibernateTemplate().find("from WpvH} l r}
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" + entity.getName()); FTB"C[>
} ?r@ZTuq#
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publicList findByNamedQuery(finalString "=RB
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namedQuery){ qItI):9U
return getHibernateTemplate M0]fh5O
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().findByNamedQuery(namedQuery); )zt5`"/o
} qH(2 0Z!
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publicList findByNamedQuery(finalString query, T xN5K`q
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finalObject parameter){ G/D{K$=t~
return getHibernateTemplate x~mXtqg
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().findByNamedQuery(query, parameter); \Z~m6;
} U%#=d@?
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publicList findByNamedQuery(finalString query, Vs"M Cqi
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finalObject[] parameters){ G(4k#jB
return getHibernateTemplate N7e^XUG
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().findByNamedQuery(query, parameters); Zdak))7
} NN$`n*;l
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publicList find(finalString query){ `ybZE+S.
return getHibernateTemplate().find 712i|
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(query); ~C[,P\,
} ' ZB%McS
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publicList find(finalString query, finalObject EuAa
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parameter){ Z`f _e?
return getHibernateTemplate().find 8=e\^Q+
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(query, parameter); OO@$jXZB
} i44`$ps
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public PaginationSupport findPageByCriteria I7TMv.
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(final DetachedCriteria detachedCriteria){ D/)xe:
return findPageByCriteria X$xqu\t7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); q80?C.,`
} SQHVgj
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public PaginationSupport findPageByCriteria #(A>yW702
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(final DetachedCriteria detachedCriteria, finalint Gh< r_O~L3
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startIndex){ ;^xku%u
return findPageByCriteria Z2ZS5a
\t(/I=E8/
(detachedCriteria, PaginationSupport.PAGESIZE, ,JjTzO
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startIndex); 4~
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} K4
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public PaginationSupport findPageByCriteria :|Z*aI]9
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(final DetachedCriteria detachedCriteria, finalint L-Hl.UV
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pageSize, D,R/abYZH
finalint startIndex){ 8
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return(PaginationSupport) \_+d*hHF~
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getHibernateTemplate().execute(new HibernateCallback(){ Gz
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publicObject doInHibernate Q!@"Y/
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(Session session)throws HibernateException { yDHH05Yl
Criteria criteria = BK-{z).)
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detachedCriteria.getExecutableCriteria(session); k6$.pCH6
int totalCount = VkUMMq{
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((Integer) criteria.setProjection(Projections.rowCount tQ*5[F,fm
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()).uniqueResult()).intValue(); |J8c|h<
criteria.setProjection QV" |
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(null); _57i[U r
List items = ?a(ApD\
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criteria.setFirstResult(startIndex).setMaxResults @UX'(W
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(pageSize).list(); Q
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PaginationSupport ps = hX<0{pXM4
}+,;wj~
new PaginationSupport(items, totalCount, pageSize, C?X^h{Tp
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startIndex); =r#of|`Q
return ps; wOn.m
} LKTIwb>
}, true); r
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} PjDYdT[
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public List findAllByCriteria(final a!]'S4JS
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DetachedCriteria detachedCriteria){ +AO(e
return(List) getHibernateTemplate '
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().execute(new HibernateCallback(){ 5hg:@i',
publicObject doInHibernate T5Yu+>3
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(Session session)throws HibernateException { %;~Vc{Xxt/
Criteria criteria = ol[
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detachedCriteria.getExecutableCriteria(session); ^cn%]X#.
return criteria.list(); -X3yCK?re
} >;LXy
}, true); a~>+I~^K5q
} *?:V)!.2z
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public int getCountByCriteria(final At@H
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DetachedCriteria detachedCriteria){ [3"k :
Integer count = (Integer) clV3x`z
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getHibernateTemplate().execute(new HibernateCallback(){ n@[_lNa4GD
publicObject doInHibernate ~.7/o0'+
@G,pM: t
(Session session)throws HibernateException { _UI*W&*
Criteria criteria = =HapCmrx8
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detachedCriteria.getExecutableCriteria(session); Pw+PBIGn4
return Z(F['Zf
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criteria.setProjection(Projections.rowCount
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()).uniqueResult(); ~?#>QN\\c
} X(_xOU)V
}, true); ad)jw:n
return count.intValue(); 1V
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} /{Mo'.=Z
} w}|XSJ!
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用户在web层构造查询条件detachedCriteria,和可选的 Ms=5*_J2Jk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 #)r^ZA&E
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PaginationSupport的实例ps。 [x%[N)U3
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ps.getItems()得到已分页好的结果集 *c<6 Er>s
ps.getIndexes()得到分页索引的数组 $-=xG&fSz
ps.getTotalCount()得到总结果数 _ sqj~|K
ps.getStartIndex()当前分页索引 JtvZ~s
ps.getNextIndex()下一页索引 `.z"Q%uz
ps.getPreviousIndex()上一页索引 .} O@<t
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3Ofh#|qc&
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ?6Wv["%
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一下代码重构了。 Q7.jSL6
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我把原本我的做法也提供出来供大家讨论吧: =X1oB,W{
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首先,为了实现分页查询,我封装了一个Page类: sWmqx$
java代码: &S=Qu?H
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/*Created on 2005-4-14*/ ppo.# p0w
package org.flyware.util.page; j0=F__H#@
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/** H:EK&$sU
* @author Joa 1M.#7;#B3
* 3@nIoN'z
*/ u/<ZGW(&s(
publicclass Page { W__Y^\~
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/** imply if the page has previous page */ a ~YrQI-@
privateboolean hasPrePage; lN&+<>a
` ZZ3!$czR
/** imply if the page has next page */ ; GE6S{~-
privateboolean hasNextPage; 3ZC@q
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/** the number of every page */ /0cm7[a ?
privateint everyPage; fWC(L s
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/** the total page number */ z;?ztpa@
privateint totalPage; 7O8 @T-f+2
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/** the number of current page */ s$zm)y5
privateint currentPage; KwV!smi2
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/** the begin index of the records by the current & kVa*O
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query */ }z#M!~
privateint beginIndex; auB
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/** The default constructor */ :Tv>)N
public Page(){ HL]J=Gh
VxS3lR=
} St(jrZb
B|V!=r1%
/** construct the page by everyPage 6&5D4
V
* @param everyPage ?w!8;xS8
* */ %I9f_5BlT8
public Page(int everyPage){ pouXt-%2X
this.everyPage = everyPage; Kxa1F,dZ
} Sk"hqF.2
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/** The whole constructor */ pH.&C 5kA
public Page(boolean hasPrePage, boolean hasNextPage, 7QnWw0
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int everyPage, int totalPage, @%*2\8}C!
int currentPage, int beginIndex){ ? %8%1d
this.hasPrePage = hasPrePage; N
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this.hasNextPage = hasNextPage; q]C_idK=
this.everyPage = everyPage; J_7@d]0R
this.totalPage = totalPage; K!qOO
this.currentPage = currentPage; !;mn]wR>a
this.beginIndex = beginIndex; ^&C/,,U
} KAD2_@l
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/** -BI!ZsC'
* @return @k)J
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* Returns the beginIndex. P_0[spmFU
*/ ,u^{zYoW
publicint getBeginIndex(){ #]5KWXC'~
return beginIndex; P
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} boCi*]
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/** Nu?A>Q
* @param beginIndex [ dVBsi
* The beginIndex to set. XEbVsw
*/ ^^7@khmNl
publicvoid setBeginIndex(int beginIndex){ ]|PTZ1?j
this.beginIndex = beginIndex; gED|2%BXb
} eR>8V8@
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/** yA"?Hv \o;
* @return YkMFU'?[
* Returns the currentPage. p`A2^FS)
*/ Xe_djy'8
publicint getCurrentPage(){ 6,jCO@!
return currentPage; %z1^
} EVZ1Z
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/** o$;&q
*
* @param currentPage &}Wi@;G]2
* The currentPage to set. +x`pWH]2
*/ S .x>w/
publicvoid setCurrentPage(int currentPage){ psmDGSm,&
this.currentPage = currentPage; U`EOun,
} oz.z>+Q
q'+ARW48
/** @w.DN)GPo
* @return gI2'[OU
* Returns the everyPage. )h 6 w@TF
*/ gy,)%{,G
publicint getEveryPage(){ ;a@riPqx!
return everyPage; D=3Z] 'A
} fgj$
u
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/** O%>*=h`P
* @param everyPage 'a JE+
* The everyPage to set. Tq)hAZ
*/ 1,OkuyXy!>
publicvoid setEveryPage(int everyPage){ /{[<J<(8
this.everyPage = everyPage; \ILNx^$EL
} D]"W|.6@
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/** P/[RH e
* @return yFmy
* Returns the hasNextPage. 3w |5%`
*/ (n>Gi;u(R
publicboolean getHasNextPage(){ ..nVViZ
return hasNextPage; iZ}c[hC'3`
} A_E2v{*n
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/** 0',buJncV
* @param hasNextPage Z}vDP^rf
* The hasNextPage to set. U*yOe*>
*/ <Rn-B).3bs
publicvoid setHasNextPage(boolean hasNextPage){ pi#a!Quf\
this.hasNextPage = hasNextPage; =$y J66e
} rX5"p!z
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/** @VIY=qh
* @return y O@1#
* Returns the hasPrePage. L'KKU4zj
*/ ?Q"<AL>Z
publicboolean getHasPrePage(){
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return hasPrePage; jP}Ry=V/
} s.;'-oA
toD!RE
/** <wFmfrx+v
* @param hasPrePage qHyOaKMd
* The hasPrePage to set. gn.)_
*/ lg
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publicvoid setHasPrePage(boolean hasPrePage){ %1#|>^
this.hasPrePage = hasPrePage; <1lB[:@%U
} FwB xag:u
m;xa}b{(i
/** Y^d#8^cP
* @return Returns the totalPage. n.NWS/v_{
* M
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*/ iKaS7lWH
publicint getTotalPage(){ /5epDDP-t5
return totalPage; &Y9%Y/Y
} Si23w'T
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/** GeB-4img
* @param totalPage XJl
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* The totalPage to set. [GK##z'5
*/ z$g__q-
publicvoid setTotalPage(int totalPage){ fn7?g
this.totalPage = totalPage; f0%'4t
} ei1;@k/
x+'Ea.^
} @_c&lToj_
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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 =\i%,YY
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个PageUtil,负责对Page对象进行构造: 9-1'jNV
java代码: #\xy,C'Y
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/*Created on 2005-4-14*/ ,}>b\(Lk
package org.flyware.util.page; 7NvRZ!
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X
import org.apache.commons.logging.Log; td$RDtW[3
import org.apache.commons.logging.LogFactory; D^];6\=.i
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/** 0R]'HA>
* @author Joa ao(Lv+
* C4dCaiX
*/ ^foCcO
publicclass PageUtil { pA@R,O>zr
*|L;&XM&/
privatestaticfinal Log logger = LogFactory.getLog 81I9xqvSd~
28}L.>5k
(PageUtil.class); v`7~#Avhz
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/** <{Rz1CMc
* Use the origin page to create a new page #&K}w0}k
* @param page 0Uk;&a0s
* @param totalRecords }C=+Tn
* @return ~Hx>yn94e
*/ 0NvicZ7VR
publicstatic Page createPage(Page page, int oHV!>K_D
RO'b)J:j9
totalRecords){ =C)2DW J1
return createPage(page.getEveryPage(), 9:E.Iy
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page.getCurrentPage(), totalRecords); 1u }2}c|
} W<~u0AyO
3
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/** >ca`0gu
* the basic page utils not including exception o7v9xm+
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handler [zCKJR
* @param everyPage ,v9*|>4
* @param currentPage mMK 93Ng"&
* @param totalRecords ]qk`Yi
* @return page s|:j~>53
*/ GgvMd~
publicstatic Page createPage(int everyPage, int )@.0ai
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currentPage, int totalRecords){ O%} hNTS"
everyPage = getEveryPage(everyPage); --7@rxv
currentPage = getCurrentPage(currentPage); ]^QO^{Sz
int beginIndex = getBeginIndex(everyPage, BGO
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H"pwIiC
currentPage); kNrd=s,-]D
int totalPage = getTotalPage(everyPage, O<?.iF%
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totalRecords); S\2@~*{-8
boolean hasNextPage = hasNextPage(currentPage, (~#-J7
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totalPage); e{ZS"e`!
boolean hasPrePage = hasPrePage(currentPage); % )}rQqQ
!~}@Eoii4
returnnew Page(hasPrePage, hasNextPage, A=wh&X
everyPage, totalPage, <EuS6Pg
currentPage, <x:^w'V_b
WG5)-;>q|
beginIndex); N8{
8 a
} s`dUie}y<
}FkF1?C
privatestaticint getEveryPage(int everyPage){ W;P8'_2Y
return everyPage == 0 ? 10 : everyPage; fvV5G,lD3h
} Ot~buf'|
qoC<qn{.a
privatestaticint getCurrentPage(int currentPage){ ByjgM`
return currentPage == 0 ? 1 : currentPage; |u^~Z-.
} GrM`\MIO
Rw`64 L_
privatestaticint getBeginIndex(int everyPage, int 4FJA+
%07vH&<C.
currentPage){ bxAHzOB(\
return(currentPage - 1) * everyPage; VVi3g
} 0gJ{fcI
Ez Xi*/
privatestaticint getTotalPage(int everyPage, int -N1X=4/fg
+)*oPSQ5
totalRecords){ )JA^FQ5N
int totalPage = 0; !/EN
s[u*~A
if(totalRecords % everyPage == 0) L&Pj0K-HT3
totalPage = totalRecords / everyPage; -)!;45
else i$XT Qr0K=
totalPage = totalRecords / everyPage + 1 ; ^-qz!ib
Mdy4H[Odq
return totalPage;
l\{r-F
N
} 8AmB0W>e
|DXi~
privatestaticboolean hasPrePage(int currentPage){ <-=g)3_
return currentPage == 1 ? false : true; (iu IeJ^Z
} SM[VHNr,-
V6r*fEhrT_
privatestaticboolean hasNextPage(int currentPage, W,[iRmxn
uP2Wy3`V
int totalPage){ 'F Cmbry
return currentPage == totalPage || totalPage == Gs(;&fw
_/h<4G6A
0 ? false : true;
xnC5WF7
} W$Z8AZ{E
o(oD8Ni
@BI;H
V%k
} G5!!^p~
.N Z
L
[X"N
;~Q`TWC
[g$IN/o%
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。 )S|&3\
NsL!AAN[V
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 QzV%m0
VN]"[
做法如下: muIJeQ.C
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Ft?Yc 5
8k?V&J `
的信息,和一个结果集List: !s[gv1
java代码: 92 1s'"
X9ec*x
ho}G]y
/*Created on 2005-6-13*/ 6Bn}W ?
package com.adt.bo; ){4$oXQ
7}vx]p2
import java.util.List; Q VWVZ >l
H=*2A!O[_
import org.flyware.util.page.Page; o>yo9n%t
P7;q^jlB
/** s~g]`/h$r
* @author Joa h`Xl~=
*/ pm:#@sl
publicclass Result { *)Pb-c
tCQf `
private Page page; JUTlJyx8
1N +ju"2R
private List content; z#+Sf.
&8hW~G>(m
/** k(_^Lq f-
* The default constructor ;:P}s4p
*/ 6' 9zpe@`
public Result(){ k<%y+v
super(); oC(.u ?
} ]{= qdgJ
S,RC;D7
/** q(}#{OO
* The constructor using fields 0#/Pc`zC
* nT@FSt
* @param page !GtCOr\'
* @param content /(Ryh6M
*/ &e5,\TQ
public Result(Page page, List content){ d>x(Bj6
this.page = page; r%%<
this.content = content; [ejl #'*5
} laaoIL^
\7 }{\hY-
/** '#CYw=S+
* @return Returns the content. l"9$lF}
*/ A7TV-eWG
publicList getContent(){ VPOp#;"%
return content; _6C,w`[[6
} P^'}3*8S
|}<!O@<|
/** q ?m<9`
* @return Returns the page. DO
,7vMO
*/ <}1GYeP
public Page getPage(){ ?^{Ey[)'(
return page; ib~EQ?u{
} fl<j]{*v
l7uEUMV
/** $"`e^J9!!
* @param content !9EbG
* The content to set. ".
wG~H
*/ A|BN>?.t
public void setContent(List content){ 9v76A~~
this.content = content; CpC6vA.R
} ]H=P(Z-
YtY.,H;
/** dx"9jFn
* @param page [I%'\CI;
* The page to set. Hv|(V3-
*/ KPdlg.
publicvoid setPage(Page page){ ~)]n67Or~
this.page = page; r }Nq"s<
} [N1[khY`
} #5_pE1
8rSu,&<
u&$1XZ!es
rvBKJ!b0
E1Rz<&L
2. 编写业务逻辑接口,并实现它(UserManager,
3vF-SgCV
+g8uV hC
UserManagerImpl) f9J]-#I if
java代码: T2i\S9X
R|dSjE s
60%EmX
;
/*Created on 2005-7-15*/ Zz56=ZX*_
package com.adt.service; ,4kipJ!,yK
K<7 Db4H
import net.sf.hibernate.HibernateException; dF0:'y
g<N3 L [
import org.flyware.util.page.Page; T!gq
Z
U%_6'5s{^
import com.adt.bo.Result; N;XJMk_ H
'2c4
4F)i
/** u^&,~n@n7
* @author Joa ;#6j9M0
*/ s&Qil07Vl
publicinterface UserManager { {$^Lb4O[V
-Khb
public Result listUser(Page page)throws ED
R*1!d
ut;KphvSH
HibernateException; R3} Z"
8rgNG7d
} Q-Rt
&\s>PvnquX
AC/8 2$
kR|(hA,$N
7(bE;(4
java代码: O8S"B6?$~'
];G$~[
U0%m*i
/*Created on 2005-7-15*/ #s'
package com.adt.service.impl; ;l6tZ]-"
:X;AmLf`2u
import java.util.List; O<v9i4*
y*5bF0
import net.sf.hibernate.HibernateException; -N[Q*;h|
sS|N.2*
import org.flyware.util.page.Page; ~
-hH#5
import org.flyware.util.page.PageUtil; q^hL[:ms#
"?Cx4<nsM
import com.adt.bo.Result; *@,>R6)jI
import com.adt.dao.UserDAO; W} U-u{Z
import com.adt.exception.ObjectNotFoundException; q"[8u ]j
import com.adt.service.UserManager; icPg<>TQ
@n##.th
/** cSSrMYX2
* @author Joa 3yfq*\_uXw
*/ &zYo
publicclass UserManagerImpl implements UserManager { -v(.]`Wo&;
DEw_dOJ(
private UserDAO userDAO; WwF4`kxT
WurpHOJt+
/** ~e<v<92Xu
* @param userDAO The userDAO to set. 6Q._zk
*/ ~agzp`!M
publicvoid setUserDAO(UserDAO userDAO){ [J|)DUjt
this.userDAO = userDAO; |&t 2jD(
} TKsze]/q
XKU+'Tz
/* (non-Javadoc) t4H@ZvAH0
* @see com.adt.service.UserManager#listUser })R8VJ&C/
*kXSl73 k
(org.flyware.util.page.Page) 0NB6S&lI^k
*/ XACbDKyS
public Result listUser(Page page)throws =x4:jas
!ACWv*pW
HibernateException, ObjectNotFoundException { Xh/i5}5 t
int totalRecords = userDAO.getUserCount(); D/w4u;E@
if(totalRecords == 0) $GyO+xF
throw new ObjectNotFoundException /]Fs3uf
7)IBIlV
("userNotExist"); Hb3+$vJ^
page = PageUtil.createPage(page, totalRecords); @83h/Wcxd
List users = userDAO.getUserByPage(page); N;A#3Ter
returnnew Result(page, users); yWACIaj
} )K8k3]y&
FKd5]am
} nBd!296
dF{3~0+,
E/<[G?
_=1SR\
sD$
\!7:b
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~ySmN}3~'
';x .ry
询,接下来编写UserDAO的代码: q!k
F
3. UserDAO 和 UserDAOImpl: \`#;J?Y|`F
java代码: :".:Wd
@.gT&Hq
JEX{jf
/*Created on 2005-7-15*/ p;:tzH\l
package com.adt.dao; `e0U-W]kF
OE-$P
import java.util.List; .9Bimhc6K
owTW_V
import org.flyware.util.page.Page; a}a_&rf~Z
*$x/(!UE
import net.sf.hibernate.HibernateException; .
({aPtSt!
hA?j"y0?
/** -vI?b#
* @author Joa {nT !|S)$
*/ %*<k5#Yq
publicinterface UserDAO extends BaseDAO { tnbaU%;|J
9U6y<X
publicList getUserByName(String name)throws -8qLshQ
N10'./c K
HibernateException; 2GcQh]ohc
;)[RG\
publicint getUserCount()throws HibernateException; ;C-5R U
V
71cc6T
publicList getUserByPage(Page page)throws 0G9@A8LU
^LTLyt)/
HibernateException; -:m;ePK
m:/@DZ
} [9a0J):w{
"*#$$e53A
q^Lj)zmnK
7i~::Z <
p*W4^2(d
java代码: <8!mmOK1
eg)=^b
iBxCk^
/*Created on 2005-7-15*/ `8\pihww
package com.adt.dao.impl; b^ly
B8Jev\_
import java.util.List; z]Z>+|
W$N_GR'4
import org.flyware.util.page.Page; BkA>':bUr
uwQ{y>SG
import net.sf.hibernate.HibernateException; kJ>l,AD/
import net.sf.hibernate.Query; w48T?
0 '~Jr\4
import com.adt.dao.UserDAO; =]\,I'
O9A.WSJ
>}
/** 4eYj.=I
* @author Joa ,y,NVF
*/ %H~q3|z
public class UserDAOImpl extends BaseDAOHibernateImpl e<l Wel
9Z6] ];8E
implements UserDAO { E92dSLhs5
mR[J Xh9s
/* (non-Javadoc) C$aiOK-]+
* @see com.adt.dao.UserDAO#getUserByName :Py/d6KK
wz9V)_V*
(java.lang.String) B~lrd#qC
*/ c 3 P
publicList getUserByName(String name)throws TWEmW&Q
Yj/S(4(h?
HibernateException {
qeBfE
String querySentence = "FROM user in class 7zVaj"N(
-}MWA>an8
com.adt.po.User WHERE user.name=:name"; aIRCz=N
Query query = getSession().createQuery G|'DAj%
JnmJN1@I
(querySentence); E4HG`_cWb
query.setParameter("name", name); g/mVd;#o
return query.list(); cA`R~o"
} N/8qd_:8
6BFtY+.y
/* (non-Javadoc) S$%T0~PR~
* @see com.adt.dao.UserDAO#getUserCount() }v;@1[.B
*/ 3:YZC9
publicint getUserCount()throws HibernateException { zW!3>(L/
int count = 0; V Z}^1e
String querySentence = "SELECT count(*) FROM +Ys<V
]B:g<}5$4
user in class com.adt.po.User"; }7IS:"tu
Query query = getSession().createQuery {|^9y]VFu
Jq l#z/z
(querySentence); >+7+ gSD#:
count = ((Integer)query.iterate().next AVOzx00U
@%O"P9;s
()).intValue(); a/NmM)
return count; bguhx3s
} zM|d9TS
=mn)].Wg
/* (non-Javadoc) 6U @3
xU`
* @see com.adt.dao.UserDAO#getUserByPage 9FP6Z[4
]ch cRc[!
(org.flyware.util.page.Page) I+!w9o2nZ
*/ RN5\,>+
publicList getUserByPage(Page page)throws wlAlIvIT
{<\nl#}5S
HibernateException { !qV{OXdrB
String querySentence = "FROM user in class w+=>b
ua0`&,a3I
com.adt.po.User"; T8Gx oNm
Query query = getSession().createQuery )p~\lM}?d
2_x}wB0P
(querySentence); 38L8AJqD
query.setFirstResult(page.getBeginIndex()) >5%
o9$|z
.setMaxResults(page.getEveryPage()); y5kqnibh@
return query.list(); 9jDV]!N4
} "w*VyD
1tDd4r?Y
} 8v8?D8\=|
*Y?rls `
SuB;Nb7r`
9.m_3"s
'\(Us^Ug
至此,一个完整的分页程序完成。前台的只需要调用 -;a}'1HOE
-7fsfcGM$
userManager.listUser(page)即可得到一个Page对象和结果集对象 RI!!?hYm
zy(sekX;
的综合体,而传入的参数page对象则可以由前台传入,如果用 :@y!5[88!
"diF$Lj
webwork,甚至可以直接在配置文件中指定。 .2q7X{4=
+XLy Pj
下面给出一个webwork调用示例: 7"yA~e,l
java代码: - jfZLO4
#Q.A)5_
yd$_XWp?\
/*Created on 2005-6-17*/ \EuMzb"G9p
package com.adt.action.user; hk3}}jc
iOkRB[hi
import java.util.List; !o+#T==p
TppR \[4]
import org.apache.commons.logging.Log; N\ChA]Ck
import org.apache.commons.logging.LogFactory; 2.{:PM4Z4
import org.flyware.util.page.Page; W=|sy-N{2
z|^:1ov,
import com.adt.bo.Result; 5%,J@&5G s
import com.adt.service.UserService; l ~CYxO
import com.opensymphony.xwork.Action; +)k%jIi!
>B<jR$`6@
/** .K]n<+zW
* @author Joa VI:
!#
*/ % 3d59O
publicclass ListUser implementsAction{ R*VRxQ,h6+
rV*9=
privatestaticfinal Log logger = LogFactory.getLog 48vKUAzx`
L'B=
=#
(ListUser.class); Tf(-Duxz
ZjF5*A8l
private UserService userService; =Y
Je\745
f40 xS7-Q0
private Page page; A:Pp;9wl
c}v>Mx
privateList users; bHZXMUewC
4WU%K`jnXb
/* .`*h2
* (non-Javadoc) )F*;7]f
* :ZX#w`Y
* @see com.opensymphony.xwork.Action#execute() = i9|lU"Va
*/ Ox9WH4E
publicString execute()throwsException{ qp$Td<'Y
Result result = userService.listUser(page); O(q1R#n-}+
page = result.getPage(); Xy/lsaVskX
users = result.getContent(); <*k]Aa3y
return SUCCESS; Mtxn@m{i;"
} 3H"bivK
6?\X)qBI
/** R@zl?>+
* @return Returns the page. $0+n0*fp
*/ 1@" L
public Page getPage(){ :+Ti^FF`w
return page; vt8z=O
} kD1[6cJ!=.
>wx1M1
/** P(h[QAM
* @return Returns the users. 'KL!)}B$h
*/ mtfEK3?2*
publicList getUsers(){ f-]5ZhM'
return users; w
K)/m`{g
} sUl/9VKl
(.D|%P
/** !.\- l2f
* @param page hf#[Vns
* The page to set. U42B(ow
*/ ZDffR:An
publicvoid setPage(Page page){ /D@(o`a
this.page = page; 8<#S:O4kA
} )GgO=J:o
qC|$0
/** s}m.r5
* @param users dJ/(u&N
* The users to set. Gh.@l\|tf
*/ O C qI
publicvoid setUsers(List users){ 9pY`_lxa>
this.users = users; T~Z7kc'
} +#$(>6Zu"{
i7 *cpNPO
/** OsSGVk #Qh
* @param userService IJnh@?BC
* The userService to set. X!'nfN
*/ Td|x~mZv:
publicvoid setUserService(UserService userService){ yEvuTgDv
this.userService = userService; jjbw+
} b0vbE8wa
} Po+tk5}''5
}3rWmo8V
0nX.%2p#Je
gJn_Z7Mg J
"?[7oI}c&
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, $
2/T]
=2BB ~\G+
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 9S_N*wC.
{1jywb
}
么只需要: \K,piCVViN
java代码: *,Mg
r]0UF0#
dE[_]2];P
<?xml version="1.0"?> #"Wh$x%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Nvef+L,v
DJm/:td
1.0//EN" "http://www.opensymphony.com/xwork/xwork- &R'%OFi
IdvBQ [Gj
1.0.dtd"> CYxrKW
l:'
HJ\CGYmyz
<xwork> OR\-%JX/5
@3UVl^T
<package name="user" extends="webwork- j5cc"s
_z3Hl?qk=
interceptors"> Vu6pl
!iOuIYjV
<!-- The default interceptor stack name h0N*hx
!`VO#_TJ
--> vGk}r
<default-interceptor-ref Nr#Y]9nA
kS>'6xXH
name="myDefaultWebStack"/> ,yC-QFQE
^z[-pTY
<action name="listUser" ?Z<2zm%qV
mndUQN_Gb
class="com.adt.action.user.ListUser"> \I\'c.$I.Y
<param ;5*)kX
9u 'hCi(
name="page.everyPage">10</param> x+O}R D*G
<result '(/ZJ88JP
S*H :/Ip
name="success">/user/user_list.jsp</result> jH*+\:UP-
</action> $Xlyc.8YId
c-INVA)
</package> #"M 'Cs
Lp \%-s#5s
</xwork> %qzpt{'?<
3q:-98DT
dkV%Pyj
!Xwp;P=
k3m|I*_\L
ta+'*@V+G
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 ;y#6Nx,:
c;w~ -7Q*|
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。 b8J\Lm|J
ou44vKzS
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Rk
PY@>
`d=$9Pi
(n-8p6x(
I `44}oJ
tR5zlm(}
我写的一个用于分页的类,用了泛型了,hoho q{UP_6OF
B{ NKDkDH
java代码: h2Ifq!(:
o'Q)V
n=RAE^[M
package com.intokr.util; |}*k|
L%a ni}V
import java.util.List; I}Z[F,}*J
pBt/vS ad
/** v@k62@;
* 用于分页的类<br> (j u-r*0
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 0D>~uNcT}
* DR9M8E
* @version 0.01 QEM")(
* @author cheng asR6,k
*/ nJ4h9`[>V
public class Paginator<E> { 0$,Ag;"^?
privateint count = 0; // 总记录数 (FMYR8H*(
privateint p = 1; // 页编号 w2~(/RgO
privateint num = 20; // 每页的记录数 wCBL1[~C
privateList<E> results = null; // 结果 w;'
F;j~
76)(G/
/** ]t1)8v2w>
* 结果总数 q4 'x'8
*/ Y[T;j p(k
publicint getCount(){ #'<I!G
return count; 5d(A(
} scqG$~O)
;ijJ%/
publicvoid setCount(int count){ ,-c(D-&
this.count = count; S:vv*5
} Rv q_Zsm
D{.%Dr?
/** 7^KQQ([
* 本结果所在的页码,从1开始 4g\a$7r
* Ffj:xZ9rk
* @return Returns the pageNo. 0 nWV1)Q0=
*/ B[4y(Im
publicint getP(){ <mY`<(bc
return p; o;];ng
} ~8pf.^,fi
bHS2;K~
/** m1F<L
* if(p<=0) p=1 gyCb\y+\a
* GeHDc[7
* @param p W]2;5`MM
*/ 2z0HB+Y}x
publicvoid setP(int p){ 9d[0i#` :q
if(p <= 0) $Q{1^
p = 1; 82J0t}:U
this.p = p; ~O1*]
} =53LapTPJ
5)$U<^uy
/** _\]D<\St
* 每页记录数量 1v2wP2]|;
*/ bq(*r:`"
publicint getNum(){ E 3I'3
return num; ljt1:@SN(
} =l7LEkR
]NFDE-Jz]
/** p*npY"}v
* if(num<1) num=1 "apv)xdW
*/ oQyG
publicvoid setNum(int num){ $}KYpSV
if(num < 1) r`B+ KQ4
num = 1; M;iaNL(
this.num = num; v$tS2N2
} ~!&[;EM<bm
~36c0 =
/** @tj0Ir v
* 获得总页数 %BG5[XQ7
*/ SD.ze(P
publicint getPageNum(){ l&|{uk
return(count - 1) / num + 1; 6op\g].P
} I^ >zr.zA
;XtDz
/** S~TJF}[k^6
* 获得本页的开始编号,为 (p-1)*num+1 \!^o<$s.G
*/ S}<
<jI-z
publicint getStart(){ -{7N]q)}
return(p - 1) * num + 1; FN,uD:a
}
;<][upn
Q`s(T
/** *ap#*}r!Nk
* @return Returns the results. }>1E,3A:%G
*/ l|fd,
publicList<E> getResults(){ (,TO|
return results; K5ph x
} Z0:BXtW
/<2_K4(-{4
public void setResults(List<E> results){ d{trO;%#f
this.results = results; b;O+QRa
} &
vIKNGJ^
ri^yal<'
public String toString(){ s-ou ;S3s
StringBuilder buff = new StringBuilder ?yU#'`q
PaZYs~EO
(); >@%!r
buff.append("{"); -s 1VlS/
buff.append("count:").append(count); :ox CF0Y
buff.append(",p:").append(p); C;ye%&g>
buff.append(",nump:").append(num); BY d3 rI
buff.append(",results:").append Ii8jY_
2uHp %fv;
(results); QezK&iJg
buff.append("}"); w&gHmi
return buff.toString(); "osYw\unI
} ,rdM{ r
PA/6l"-`3
} RW)C<g
S=2,jPX2r
IviWS84