Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 =>|C~@C?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 06 i;T~Y
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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 Zp&@h-%YoD
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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 rkB'Hf
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分页支持类: w8Vw1wW
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java代码: HpVjee
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package com.javaeye.common.util;
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import java.util.List; @F~LW6K
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publicclass PaginationSupport { jZpa0g rA
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publicfinalstaticint PAGESIZE = 30; ;`dh
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privateint pageSize = PAGESIZE; w%y\dIeI'
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privateList items; pI.+"Hz
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privateint totalCount; QA#3bFZt1n
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privateint[] indexes = newint[0]; )IL
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privateint startIndex = 0; l;A,0,i
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public PaginationSupport(List items, int Q=uR Kh
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totalCount){ FV39QG4b4
setPageSize(PAGESIZE); 4|?{VQ
setTotalCount(totalCount); Oakb'
setItems(items); $wB^R(f@
setStartIndex(0); bFS>)
} q.#[TI ^
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public PaginationSupport(List items, int R\|lt)h
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totalCount, int startIndex){ S=`+Ryc
setPageSize(PAGESIZE); Lw1EWN6}_&
setTotalCount(totalCount); 6K`c/)
setItems(items); )D&M2CUw"f
setStartIndex(startIndex); cO2& VC
} !4"^`ors$
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public PaginationSupport(List items, int fBn"kr;
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totalCount, int pageSize, int startIndex){ %V`F!D<D
setPageSize(pageSize); l v&mp0V+
setTotalCount(totalCount);
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setItems(items); g7V8D
setStartIndex(startIndex); U9y|>P\)T
} xo}b=
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publicList getItems(){ g>rp@M
return items; l%ayI
} $rF=_D6
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publicvoid setItems(List items){ TL$EV>Nr
this.items = items; b-U
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} =L|tp%!
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publicint getPageSize(){ w%AcG~`j!B
return pageSize; KlV:L 4a~
} $
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publicvoid setPageSize(int pageSize){ :A
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this.pageSize = pageSize; u]NZ`t%AP
} ,;?S\V
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publicint getTotalCount(){ QxuhGA
return totalCount; 99$
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} fj7|D'c
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publicvoid setTotalCount(int totalCount){ 'i;|c
if(totalCount > 0){ 8dD2
this.totalCount = totalCount; ]5~s"fnG
int count = totalCount / T _b^ Tc`
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pageSize;
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if(totalCount % pageSize > 0) D jk C
count++; :j|IP)-f
indexes = newint[count]; c4&' D;=
for(int i = 0; i < count; i++){ HEL!GC>#
indexes = pageSize * yR{x}DbG
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i; g %K>
} /@AEJ][$
}else{ 1im^17X
this.totalCount = 0; o"wXIHUmV
} 8+]hpa,q
} P%)gO
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publicint[] getIndexes(){ ,+`61J3W
return indexes; m9U"[Huv1E
} 4Mk-2 Dx
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publicvoid setIndexes(int[] indexes){ yc|VJ2R*
this.indexes = indexes; n JPyM/p
} UobyK3.%
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publicint getStartIndex(){ ^pM+A6
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return startIndex; 8/)qTUx:
} gP+fN$5'd
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publicvoid setStartIndex(int startIndex){ I`z@2Z+pJ
if(totalCount <= 0) jx acg^c
this.startIndex = 0; %| G"-%_E
elseif(startIndex >= totalCount) hhoEb(BA
this.startIndex = indexes s2j['g5
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[indexes.length - 1]; Sa19q.~%
elseif(startIndex < 0) wts=[U`(
this.startIndex = 0; qfcYE=
else{ d #jK=:eK
this.startIndex = indexes (98Nzgxgx}
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[startIndex / pageSize]; drsB/
} r>bJ%M}
} hHqh{:q{v
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publicint getNextIndex(){ ]kG(G%r|M
int nextIndex = getStartIndex() + nx0K$Ptq
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pageSize; Q f(p~a(d
if(nextIndex >= totalCount) "`6n6r42
return getStartIndex(); j5@:a
else lI>SUsQFfm
return nextIndex; =_YG#yS
} !|c|o*t{
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publicint getPreviousIndex(){ |lv|!]qAma
int previousIndex = getStartIndex() - tpuYiL
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pageSize; &~CY]PN.
if(previousIndex < 0) Q]p(u\*
return0; 2Pc%fuC
else 6"dD2WV/
return previousIndex; ?`J[[",
} gk`zA
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} 1
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抽象业务类 +MmHu6"1
java代码: b%cF
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/** &>H!}"Yk
* Created on 2005-7-12 !Ra*)b"
*/ =~p>`nV
package com.javaeye.common.business; -\#0]F:-
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import java.io.Serializable; /rSH"$
import java.util.List; Ks}Xgc\
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import org.hibernate.Criteria; KF4PJi;*
import org.hibernate.HibernateException; z5TuGYb<
import org.hibernate.Session; %6_AM
import org.hibernate.criterion.DetachedCriteria; qTQBt}
import org.hibernate.criterion.Projections; Z(!00^
import o6//IOZ
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org.springframework.orm.hibernate3.HibernateCallback; jv&!Kw.Ug
import fxT-j s#S
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org.springframework.orm.hibernate3.support.HibernateDaoS /a6Xa&(B
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upport; eilYA_FL.
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import com.javaeye.common.util.PaginationSupport; $v Z$'(
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public abstract class AbstractManager extends YM
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HibernateDaoSupport { b:w?PC~O
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privateboolean cacheQueries = false; ;`6^6p\p
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privateString queryCacheRegion; 2YDM9`5xs\
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publicvoid setCacheQueries(boolean MMj9{ou
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cacheQueries){ ;D$)P7k6
this.cacheQueries = cacheQueries; _2N$LLbg
} D1&A,2wO
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publicvoid setQueryCacheRegion(String o;?/HE%,[
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queryCacheRegion){ NB<A>baL*
this.queryCacheRegion = !A%<#Gjt
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queryCacheRegion; }*L(;r)q
} <qGu7y"
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publicvoid save(finalObject entity){ q&d~
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getHibernateTemplate().save(entity); 6&/T@LQYrh
} RZ+`T+zL
p QizJ6
publicvoid persist(finalObject entity){ o*J3C>
getHibernateTemplate().save(entity); 4^URX>nx8
} H<3I 5Kgt
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publicvoid update(finalObject entity){ ooQQ-?"m
getHibernateTemplate().update(entity); NC38fiH_N
} 7.`fJf?
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publicvoid delete(finalObject entity){ @*sWu_-Y%
getHibernateTemplate().delete(entity); s-v
} #f+$Ddg*
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publicObject load(finalClass entity, )P+7PhE{J
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finalSerializable id){ & \f{E\A#
return getHibernateTemplate().load s;A@*Y;v
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(entity, id); ow]053:i
} ZMq6/G*fD
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publicObject get(finalClass entity, ukUGvK
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finalSerializable id){ vuYSVI2=H
return getHibernateTemplate().get O6OP =K!t:
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(entity, id); 1@-Ns
} <%"b9T`'
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publicList findAll(finalClass entity){ ?F3h)(}
return getHibernateTemplate().find("from G
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" + entity.getName()); =y-@AU8
} $b mLu=9
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publicList findByNamedQuery(finalString tdu$pC6
p }~qf
namedQuery){ % oo2/aF
return getHibernateTemplate pJtex^{!:
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().findByNamedQuery(namedQuery); P ! _rEV
} O`<KwUx !
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publicList findByNamedQuery(finalString query, r%+V8o
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finalObject parameter){ Bf8jPa/
return getHibernateTemplate v%iflCK
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().findByNamedQuery(query, parameter); @qYp>|AF
} Uw7h=UQh
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publicList findByNamedQuery(finalString query, MpR2]k#n<
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finalObject[] parameters){ b"{'T]"*j
return getHibernateTemplate N=7pK&NHSG
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().findByNamedQuery(query, parameters); 5f 5f0|ok
} :w^Ed%>y7
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publicList find(finalString query){ *vwbgJG! *
return getHibernateTemplate().find W}mn}gTQ
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(query); R)m'lMi|
} \r+8qC[,
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publicList find(finalString query, finalObject V6,H}k
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parameter){ ]%u@TK7
return getHibernateTemplate().find K42K!8$
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(query, parameter); z+n,uHs
} Jh!I:;/
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public PaginationSupport findPageByCriteria #$8% w
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(final DetachedCriteria detachedCriteria){ $cU!m(SILQ
return findPageByCriteria $arK(
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8p:e##%
} CmoE_8U>
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public PaginationSupport findPageByCriteria R[hzMU}KB
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(final DetachedCriteria detachedCriteria, finalint 7\ s"o&G
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startIndex){ IHv[v*4:
return findPageByCriteria )x=1]T>v"'
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(detachedCriteria, PaginationSupport.PAGESIZE, Eu@huN*/
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startIndex); c2'Lfgx4
} &keR~~/
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public PaginationSupport findPageByCriteria M:[ %[+6
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(final DetachedCriteria detachedCriteria, finalint (<xfCH
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pageSize, [QoK5Yw{
finalint startIndex){ GkTiDm?
return(PaginationSupport) 3@$,s~+ 3
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getHibernateTemplate().execute(new HibernateCallback(){ 9\mLW"
publicObject doInHibernate 1e{IC=
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(Session session)throws HibernateException { Gsq00j
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Criteria criteria = 2Ay*kmW
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detachedCriteria.getExecutableCriteria(session); nz=GlO'[
int totalCount = q(.sq12<<W
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((Integer) criteria.setProjection(Projections.rowCount I%j|D#qY:T
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()).uniqueResult()).intValue(); 87
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criteria.setProjection .yqM7U_
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(null); gv-xm
List items = %4,O 2\0?&
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criteria.setFirstResult(startIndex).setMaxResults YA_c
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(pageSize).list(); v,-HU&/*B
PaginationSupport ps = g4=pnK8
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new PaginationSupport(items, totalCount, pageSize, ;S^'V
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startIndex); Vk
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return ps; 8"2=U6*C
} Mb|a+,:>3
}, true); :toh0oB[
} K}buH\yco
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public List findAllByCriteria(final #~2%)
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DetachedCriteria detachedCriteria){ D%OQ e#!
return(List) getHibernateTemplate jHE}qE~>5
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().execute(new HibernateCallback(){ =S+wCN
publicObject doInHibernate ;o2$
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(Session session)throws HibernateException { bYpntV
Criteria criteria = t^R][Ay&
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detachedCriteria.getExecutableCriteria(session); ' g=
return criteria.list(); cdl&9-}
} Zw5Ni Xj
}, true);
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} vNV/eB8#S
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public int getCountByCriteria(final aeFe!`F
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DetachedCriteria detachedCriteria){ [!HEQ8 2g
Integer count = (Integer) "GMBjT8
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getHibernateTemplate().execute(new HibernateCallback(){ f33 2J
publicObject doInHibernate SPX$U5&
Z_};|B}
(Session session)throws HibernateException { =9O^p@Q#W
Criteria criteria = .h@rLorm>
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detachedCriteria.getExecutableCriteria(session); R_W+Ylob
return n'wU;!W9
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criteria.setProjection(Projections.rowCount BP'36?=Zo
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()).uniqueResult(); 42_`+Vt]d7
} wSzv|\
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}, true); 591>rh)
return count.intValue(); +7D|4
} Pk{_(ybaY
} =9y[1t
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用户在web层构造查询条件detachedCriteria,和可选的 1an^1!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 .zA^)qgL
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PaginationSupport的实例ps。 <k eVrCR
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ps.getItems()得到已分页好的结果集 gp};D
ps.getIndexes()得到分页索引的数组 [;4g
ps.getTotalCount()得到总结果数 GY6`JWk
ps.getStartIndex()当前分页索引 .b3Qfxc>
ps.getNextIndex()下一页索引 nrL9
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ps.getPreviousIndex()上一页索引 /\ y?Y
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 wKtl+}}
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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 /[a~3^Gs^
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一下代码重构了。 6Z>FTz_
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我把原本我的做法也提供出来供大家讨论吧: UldXYtGe
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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: N=4G=0 `ke
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/*Created on 2005-4-14*/ V, Z|tB^
package org.flyware.util.page; s1MErd
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/** nF54tR[
* @author Joa |'.*K]Yp
* 1Ce@*XBU
*/ yQ_B)b
publicclass Page { r54&XE]O
!*s?B L
/** imply if the page has previous page */ iqC|G/
privateboolean hasPrePage; _7Rr=_1}
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/** imply if the page has next page */ JmF l|n/H
privateboolean hasNextPage; F |d\k Q
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/** the number of every page */ j-4VB_N@
privateint everyPage; AYt%`Y.!
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/** the total page number */ X\]L=>]C
privateint totalPage; l Q'I
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/** the number of current page */ NTdixfR
privateint currentPage; (_niMQtF}
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/** the begin index of the records by the current ]9YJ,d@J
$yn];0$J
query */ ^`*9QjY
privateint beginIndex; Y'c>:;JEe
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/** The default constructor */ KX76UW
public Page(){ HFKfkAl
) brVduB
} q4R5<LW"
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/** construct the page by everyPage whmdcVh.
* @param everyPage Vr )<\h
* */ b=g8eMm
public Page(int everyPage){ GQ t8p[!
this.everyPage = everyPage; gD,1 06%
} -9%:ilX~
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/** The whole constructor */ r;B8i!gD
public Page(boolean hasPrePage, boolean hasNextPage, \.C+ue
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int everyPage, int totalPage, $}<PL}+
int currentPage, int beginIndex){ E.r>7`E
this.hasPrePage = hasPrePage; /,89p&h
this.hasNextPage = hasNextPage; 1%EBd%`#
this.everyPage = everyPage; #D<C )Q
this.totalPage = totalPage; bP8Sj16q
this.currentPage = currentPage; O;z,qo X
this.beginIndex = beginIndex; ~rlB'8j(
} ~?D4[D|sB
9)y/:sO<P
/** _76PIR{an
* @return bHPYp5UwN
* Returns the beginIndex. CUO+9X-<8
*/ EqyeJq .
publicint getBeginIndex(){ K-e9>fmB#
return beginIndex; sc|_Q/`\.
} o]+z)5zC
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/** J{l1nHQZSu
* @param beginIndex )hd@S9Z.Y
* The beginIndex to set. VCu{&Sh*
*/ u6M.'
publicvoid setBeginIndex(int beginIndex){ g$7{-OpB
this.beginIndex = beginIndex; !;EjB*&
} Fgk ajig
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/** ?5U2D%t
* @return +EFgE1w
* Returns the currentPage. g'pK
*/ +1Vjw'P
publicint getCurrentPage(){ 1q~+E\x
return currentPage; 0]>u)%
} +!k&Yje
H9KKed47d/
/** N8!cO[3Oh
* @param currentPage {s)+R[?m<o
* The currentPage to set. %u`8minCt
*/ J1/?JfF
publicvoid setCurrentPage(int currentPage){ BHd&yIyI
this.currentPage = currentPage; k]W[`
} GT~)nC9f
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/** ]Oh@,V8
* @return
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* Returns the everyPage. M^MdRu
*/ l*ayd>`~x
publicint getEveryPage(){ \qR7mI/*
return everyPage; `Y
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} 4FEk5D
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/** n?A6u\sQ
* @param everyPage +~'865 {
* The everyPage to set. wQv'8A_}
*/ ie;]/va
publicvoid setEveryPage(int everyPage){ R#xCkl -
this.everyPage = everyPage; UQ8M~x5$3%
} 'Hc-~l>D
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/** - d8TD*^
* @return @_U;9)
* Returns the hasNextPage. ,^?^dB
*/ bnm
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publicboolean getHasNextPage(){ D Gr>
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return hasNextPage; BsBK@+ZyI
} {xwm^p(f
2uG0/7
/** l-K9LTd
* @param hasNextPage cYFiJJLG]
* The hasNextPage to set. j H19k}D
*/ Acnl^x7Y1
publicvoid setHasNextPage(boolean hasNextPage){ e.]K L('
this.hasNextPage = hasNextPage; i7]4W
} L/wD7/ODr
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/** \x)n>{3C
* @return :Mb%A
* Returns the hasPrePage. M>DaQ`b
*/ kz{/(t
publicboolean getHasPrePage(){ "Weg7mc#
return hasPrePage; +hvO^?4j
} `1'6bp`Z
i\1TOP|h
/** Rz(QC\(
* @param hasPrePage -9"['-WH,
* The hasPrePage to set. 'I_Qb$
*/ 0zo?eI
publicvoid setHasPrePage(boolean hasPrePage){ 9dFy"yxYa
this.hasPrePage = hasPrePage; +cIUGFp}
} UjaK&K+M?
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/** J%x6
* @return Returns the totalPage. xm%Um\Pb7
* =jlt5 z
*/ VGtC)mG8)
publicint getTotalPage(){ &Ts-a$Z7?S
return totalPage; O_$m!5ug
} zV:pQRbt.
&$"i,~q^b
/** Xg<*@4RD8
* @param totalPage ]GN7+8l
* The totalPage to set. sW)Zi
*/ ld3-C55
publicvoid setTotalPage(int totalPage){ -M%_\;"de
this.totalPage = totalPage; [`p=(/I&L
} /b]oa!
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} q2. XoCf
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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 ;FBUwR}
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个PageUtil,负责对Page对象进行构造: $wmvKQc{lx
java代码: D!.[q -<
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/*Created on 2005-4-14*/ ) _mr! z(S
package org.flyware.util.page; @Gx.q&H
1c<=A!"{
import org.apache.commons.logging.Log; m<{<s T
import org.apache.commons.logging.LogFactory; .jS~By|r
#k_HN}B
/** (Q%'N3gk
* @author Joa ~\=1'D^6CK
* 7:9.&W/KE
*/ L !=4N!j
publicclass PageUtil { _7IKzUn9g[
)N=NR2xBZ
privatestaticfinal Log logger = LogFactory.getLog M7+nW ; e%
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(PageUtil.class); d*A*y ^OD
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/** \]P!.}nX#
* Use the origin page to create a new page _Dym{!t
* @param page A$#p%yb
* @param totalRecords 6fd+Q
/
* @return xZ|Y?R5m
*/ GytXFL3`:
publicstatic Page createPage(Page page, int s:p[DEj-
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totalRecords){ WA]c=4S
return createPage(page.getEveryPage(), ]Tkc-ez
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page.getCurrentPage(), totalRecords); :!5IW?2
} 5QPM t^
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/** }:u~K;O87
* the basic page utils not including exception FL(6?8zK
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handler Mu{;vf|j
* @param everyPage *c%oN
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* @param currentPage o&`<+4
i
* @param totalRecords 2WtRJi?b|
* @return page F#5B<I
*/ 2P/K
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publicstatic Page createPage(int everyPage, int c6nflk.l
tjGd )
currentPage, int totalRecords){ OR}c)|1
everyPage = getEveryPage(everyPage); 8<.C3m
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currentPage = getCurrentPage(currentPage); F;gx%[$GX
int beginIndex = getBeginIndex(everyPage, JNkwEZhHyg
vhsk0$f
currentPage); A81ls#is
int totalPage = getTotalPage(everyPage, U+)xu>I
w"SoeU
totalRecords); YyTSyP4
boolean hasNextPage = hasNextPage(currentPage, e=4+$d
oI}kH=<,
totalPage); DA2}{
boolean hasPrePage = hasPrePage(currentPage); UilMv~0
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returnnew Page(hasPrePage, hasNextPage, Row)hx8
everyPage, totalPage, S+'rG+NJ
currentPage, SfJ./ny
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beginIndex); UlAzJO6"
} Pcu#lWC$
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privatestaticint getEveryPage(int everyPage){ ,WJH}(h"D
return everyPage == 0 ? 10 : everyPage; io#&o;M<
} ]UH`Pdlt
Si_%Rr&jW
privatestaticint getCurrentPage(int currentPage){ &VV~%jl;k
return currentPage == 0 ? 1 : currentPage; P(XaTU&-
} @+9<O0
%^1cyk
privatestaticint getBeginIndex(int everyPage, int ,WvY$_#xW%
v^ zu:Z*
currentPage){ oP!;\a( SL
return(currentPage - 1) * everyPage; -O&CI)`;B
} VH=S?_RY>
PH>
b-n
privatestaticint getTotalPage(int everyPage, int Zs}5Smjl;%
SB5&A_tr
totalRecords){ tID%}Z v
int totalPage = 0; &}?$i7x5
;5tazBy&:C
if(totalRecords % everyPage == 0) zo[[>MA
totalPage = totalRecords / everyPage; ^|/](
else 1gmt2>#v%
totalPage = totalRecords / everyPage + 1 ; U5-@2YcH
d'/TdVM
return totalPage; MXzVgy
} "y_#7K
%H]lGN)
privatestaticboolean hasPrePage(int currentPage){ X=Ys<TM,
return currentPage == 1 ? false : true; TQ{Han!
} }|5VRJA
-T&.kYqnb$
privatestaticboolean hasNextPage(int currentPage, e.@uhB.
-S$1Yn
int totalPage){ >m#e:[N
return currentPage == totalPage || totalPage == }';D]c
m=:4`_0Q
0 ? false : true; e|&6$A>4]
} `5~ +,/Ys
$2M#qkik-
[74F6Qp
} H(Q.a=&4!p
T"&)&"W*U
FL8g5I
- !>}_AH
OvUI@,Ef
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 'yV?*a
b8%C*r7
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 WBN w~|DO]
>0dv+8Mn
做法如下: 63.wL0~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 c\ia6[3sX
B 9T!j]'
的信息,和一个结果集List: Rb%%?*|
java代码: E[O<S B
I
n @?4b8"
_:X|.W
/*Created on 2005-6-13*/ p|Q*5TO
package com.adt.bo; !<UJ6t}
7C$
5
import java.util.List; cZ(elZ0~
0b/ WpP
import org.flyware.util.page.Page; zOV=9"~{
2-"0 ^n{
/** ;U<rc'qE
* @author Joa Iw<j T|y)
*/ @^;j)%F}
publicclass Result { N? 5x9duK
=7m}yDs6$
private Page page; l3Lyea:
S a4W`
private List content; kN%MP6? J
&AlJ "N|
/** ?7M.o
* The default constructor *loOiM\5a
*/ -F=v6N {
public Result(){ @xeAc0.^
super(); =
pI?A^
} TLd `1Ac
[kqYfY?K
/** C-8qj>
* The constructor using fields =1P6Vk
* h Xb%;GL
* @param page Qfky_5R\
* @param content T]j.=|,d
*/ Wd0[%`dq
public Result(Page page, List content){ .<z!3O&L
this.page = page; dgDy5{_
this.content = content; ATy*^sc&"
} <BSc* 9Q
8)kLV_+%
/** 'S[++w?Qq
* @return Returns the content. RJy=pNztm
*/ VR
publicList getContent(){ ltkI}h,e
return content; %?aS#4jI
} pGSai&
Yk42(!
/** ?x^z]N|P
* @return Returns the page. ~V/?H!r'{}
*/ 2kv7UU#q2
public Page getPage(){ `)qVF,Z}
return page; h(qQsxIOhS
} pDQ}*
lc_E!"1
/** EwS!]h?
* @param content lpRR&
* The content to set. f30Pi1/h=c
*/ 6YuY|JD
public void setContent(List content){ Iyd?|f"
this.content = content; T~fmk
f$
} %+ FG ,d
[ >^PRs
/** Q#(GI2F2#
* @param page 0 a~HiIh
* The page to set. ZhNdB
*/ 2"fO6!hh
publicvoid setPage(Page page){ ^'p|!`:
this.page = page; A~Xq,BxCV
} zZiJ 9 e
} m=Q[\.Ra
<*t4D-os
U!XS;a)
A:y.s;<L0
c}[+h5
2. 编写业务逻辑接口,并实现它(UserManager, 5/gDK+%4D(
dq IlD!
UserManagerImpl) eZr&x~]
-w
java代码: =<@\,xN>C
w#N?l!5
-o+74=E8[?
/*Created on 2005-7-15*/ =pA
IvU
package com.adt.service; ^E6d`2w-
'a^{=+
import net.sf.hibernate.HibernateException; pG^}Xf2a
cECi')
import org.flyware.util.page.Page; htm{!Z]s0
q>s-Y|
import com.adt.bo.Result; 4wi(?
CSV;+,Vv
/** +,50qN:%[
* @author Joa {B*W\[ns
*/ 0F#>CmD
publicinterface UserManager { 4f~["[*ea
ES<{4<Kpx
public Result listUser(Page page)throws _MWM;f`b
j#0j)k2Q
HibernateException; O:#+%
M=xQ=j?
} vG^#Sfgtw
hF3&i=;.
j5Un1
>)_ojDO
5]1leT
java代码: ec Oy6@UDY
d7cg&9+
!3oKmL5
/*Created on 2005-7-15*/ $KjTa#[RX7
package com.adt.service.impl; kCUT ^
w62=06`@
import java.util.List; Q,Z*8FH=
`(0LK%w
import net.sf.hibernate.HibernateException; gPzL*6OSA
h{lDxOH*
import org.flyware.util.page.Page; j<pw\k{i
import org.flyware.util.page.PageUtil; AGYm';z3
,}xbAA#
import com.adt.bo.Result; P6Bl
*@G
import com.adt.dao.UserDAO; 6zIgQ4Bp24
import com.adt.exception.ObjectNotFoundException; *m+5Pr`7
import com.adt.service.UserManager; U-0#0} _
HNa]H;-+5
/** NYABmI/0c
* @author Joa Ip}Vb6}
*/ rVQX7l# YI
publicclass UserManagerImpl implements UserManager { rOD1_X-
_SZ5P>GIU
private UserDAO userDAO; RA a[t :|
1Q}mf !Y
/** IGFGa@C
* @param userDAO The userDAO to set. +TeFt5[)h
*/ Fk^3a'/4KJ
publicvoid setUserDAO(UserDAO userDAO){ lEPAP|~uw
this.userDAO = userDAO; {OT:3SS7
} j1Yq5`ia
7.<^j[?
/* (non-Javadoc) WW@"Z}?k
* @see com.adt.service.UserManager#listUser &jV_"_3n
~9D~7UR
(org.flyware.util.page.Page) ^_p%Yv
*/ d0er^ ~
public Result listUser(Page page)throws %u p}p/?
;52'}%5
HibernateException, ObjectNotFoundException {
Jf:,y~mV
int totalRecords = userDAO.getUserCount(); +rNkN:/L
if(totalRecords == 0) TrE3S'EU#R
throw new ObjectNotFoundException YpdNX.P,
FM^9}*
("userNotExist"); <c,~aq#W'
page = PageUtil.createPage(page, totalRecords); ++[5q+b
List users = userDAO.getUserByPage(page); d]0a%Xh[
returnnew Result(page, users); W( *V2<$o
} ~3WL)%
Q
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} `GQ{*_-
RE46k`44
6R}j-1
<n
a0Oe:]mo\
-E&e1u,Mi
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ul5|.C
!)Ni dG
询,接下来编写UserDAO的代码: ]Ql 0v"` F
3. UserDAO 和 UserDAOImpl: OCyG_DLT$5
java代码: !UV5zmS
N:+
taz-
d<o.o?Vc
/*Created on 2005-7-15*/ ;5|1M8]=0
package com.adt.dao; Sm3u /w!
#j@OLvXh
import java.util.List; Yq'4e[i
~krS#\
import org.flyware.util.page.Page; ?~ULIO'
9$d.P6|d>
import net.sf.hibernate.HibernateException; >`V}U*}*H
e`UQz$4!
/** 9\O(n>
* @author Joa `U`#I,Ln[
*/ 3"
Vd==oK~
publicinterface UserDAO extends BaseDAO { e (\I_
'Am- vhpm
publicList getUserByName(String name)throws rjojG59U>
'u[%}S38
HibernateException; ;\b@)E}
L&w.j0fq
publicint getUserCount()throws HibernateException; =_=*OEgO]
*:_~Nn9_R;
publicList getUserByPage(Page page)throws /Ic[N&
y62%26 [
HibernateException; R"6;NPeo
2z2`
} |w)5;uQ&\
2wh#$zGy
X:q_c =X
o<VP'F{p
!Rw&DFU
java代码: $Tl<V/
k
khE}qSD
iQ`]ms+
/*Created on 2005-7-15*/ -Wo15O"
package com.adt.dao.impl; Y_H/3?b%
Ky9W/dCR
import java.util.List; !sIwFv)
]rX9MA6
import org.flyware.util.page.Page; sB7" 0M
o)]FtL:mm
import net.sf.hibernate.HibernateException; y$oW!
import net.sf.hibernate.Query; i2F(GH?p[
aw$Y`6,S
import com.adt.dao.UserDAO; xks?y.wA
zNtq"T [
/** Lx+`<<_dJ
* @author Joa g6' !v
*/ IcoowZZ
public class UserDAOImpl extends BaseDAOHibernateImpl 70iH0j)
>!BFt$sd
implements UserDAO { H7e /
r,'O).7
/* (non-Javadoc) /7p>7q9g
* @see com.adt.dao.UserDAO#getUserByName *TnzkNN_,
nxRwWj57
(java.lang.String) G=$}5; t
*/ 3V-6)V{KaE
publicList getUserByName(String name)throws c f*zejbw
9) ea.Gu
HibernateException { <aVfJd/fT
String querySentence = "FROM user in class k=uZ=tUft*
sv=^k(d3
com.adt.po.User WHERE user.name=:name"; WN0c%kz=
Query query = getSession().createQuery ;QPy:x3
nPf'ee
(querySentence); ,f<B}O
query.setParameter("name", name); &va*IR
return query.list(); YX;nMyD?~
} FzhT$7Gw
iG-N
/* (non-Javadoc) BED@?:U# h
* @see com.adt.dao.UserDAO#getUserCount() ?aJ6ug
*/ xwLy|&
publicint getUserCount()throws HibernateException { IK?]PmN4}
int count = 0; S:Xs'0K_
String querySentence = "SELECT count(*) FROM (Jpm
K O
lPS*-p#IZ
user in class com.adt.po.User"; &7][@v
Query query = getSession().createQuery /co%:}ln
j`9Nwa
(querySentence); BTs0o&}e
count = ((Integer)query.iterate().next "_)|8|gN
#JS`e_3Rr
()).intValue();
SsRVd^=;x
return count; JN^bo(kb
} k /^g*
_80ns&q
/* (non-Javadoc) vf_OQ4'G,
* @see com.adt.dao.UserDAO#getUserByPage t?.\|2
u\5g3BH
(org.flyware.util.page.Page) d$Em\*C
*/ {G.jB/
publicList getUserByPage(Page page)throws Z:^3Fm->+
^srs$
w]
HibernateException { Mdm0g
String querySentence = "FROM user in class >)sqh ~P
|8'B/
p=
com.adt.po.User"; s!`H
Query query = getSession().createQuery T9y768%
uN(b.5y
(querySentence); L]>4Nd
query.setFirstResult(page.getBeginIndex()) xN"wF-s4?
.setMaxResults(page.getEveryPage()); {Y"8~
return query.list(); ||f vKyKW>
} Q
3X
cuMc*i$w!
} &CO|Y(+
}{=8&gA0
/&QQ p3
x_|>n<Z
qOgtGN}k
至此,一个完整的分页程序完成。前台的只需要调用 bQV("~#
2$)mC9
userManager.listUser(page)即可得到一个Page对象和结果集对象 1gk0l'.z
x
Ty7lfSe
的综合体,而传入的参数page对象则可以由前台传入,如果用 N6BNzN}-P
pj@Yqg/
webwork,甚至可以直接在配置文件中指定。 w5Z2N[hy
9b%|^.B
下面给出一个webwork调用示例: [yvt1:q
java代码: %t{Sb4XZ4k
^\{J5
~zj"OG"zOw
/*Created on 2005-6-17*/ S|) J{~QH
package com.adt.action.user; @Q3, bj
%xpd(&)n
import java.util.List; Yg|"-
BDp:9yau
import org.apache.commons.logging.Log; rFO_fIJno
import org.apache.commons.logging.LogFactory; 1^tSn#j
import org.flyware.util.page.Page; zM\IKo_"
)1K! [W}t
import com.adt.bo.Result; mCK],TOA:
import com.adt.service.UserService; Mb~~A5
import com.opensymphony.xwork.Action; b_ZNI0Hp@
Seg#s.
/** k!9=
* @author Joa HoV{U zm
*/ PJ0Jjoh"Y
publicclass ListUser implementsAction{ k_BSY=$e*D
3Mxz_~
privatestaticfinal Log logger = LogFactory.getLog q>P[n z%
S_j1=6#^
(ListUser.class); IY03"
9D%qXU
private UserService userService; q$|0)}
L1rAT
private Page page; Pwg/Vhfh
:+<t2^)rD
privateList users; EZ*t$3.T
Dl&PL
/* xg{VP7
* (non-Javadoc) f~U#z7
* G~`'E&/
* @see com.opensymphony.xwork.Action#execute() U-1VnX9m
*/ %kJh6J
publicString execute()throwsException{ nZ541o@t9
Result result = userService.listUser(page); xl|ghjn
page = result.getPage(); $\0TD7p
users = result.getContent(); OCwW@OC +
return SUCCESS; 98h :X %
} VZt;P%1;h
\u{Jf'g
/** R
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* @return Returns the page. G I&qwA
*/ An/>05|
public Page getPage(){ 9}.,2JE
return page; j6RJC
} 8 NxUx+]
%l%=Dkss
/** L,E-z_<p
* @return Returns the users. ^M[#^wv,
*/ A\Lr<{Jh
publicList getUsers(){ W;q#ZD(;
return users; AL(n*,
} i[o&z$JO
sN"p5p
/** /4(Z`e;0
* @param page 'lxLnX
* The page to set. }!eF
*/ \moZ6J
publicvoid setPage(Page page){ !p-'t]
this.page = page; KSF5)CZ5
} =_K%$y*
l}dj{s
/** CM`x>J
* @param users mgk64}K [n
* The users to set. u):X>??
*/ 9)#gtDM%J
publicvoid setUsers(List users){ Ewa[Y=+tx
this.users = users; "9)1K!tH
} Gs^(YGtU
6{cybD`Ef&
/** N9`y,Cos0
* @param userService #"=%b
e3
* The userService to set. =|^X$H
*/ q2[+-B)m
publicvoid setUserService(UserService userService){ BT&rp%NO6l
this.userService = userService; czXI?]gg,
} <+ -V5O^
} 7^n,Tig
&*X3ch
(PRaiE
s4!|v`+$M
nrxjN(9V%+
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, ac2}3$u
N;e;4,_ n
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 rdORNlK&
s4MNVT
么只需要: 'hxs((['\
java代码: (3)C_Z
QBg}2.
-fb1cv~N
<?xml version="1.0"?> /E=h{|
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork jXc5fXO
N
d,Hf-zJ%~
1.0//EN" "http://www.opensymphony.com/xwork/xwork- j4.Qvj >:4
$I?=.:<+
1.0.dtd"> p=:7 atE
(2\l i{$e
<xwork> `=_7I?
0L3Bo3:k
<package name="user" extends="webwork- gubb .EY
=YS!soO
interceptors"> ]hCWe0F
{LR#(q$1
<!-- The default interceptor stack name 6|B a
>qSO,$
--> z'5;f;
<default-interceptor-ref ^4n2
-DvG
.F{}~K]
name="myDefaultWebStack"/> { Hktu|
a7QlU=\
<action name="listUser" eyI-s9#t
&xPOp$Sx~
class="com.adt.action.user.ListUser"> `XQx$I
<param ;`X`c
J>,'P^
name="page.everyPage">10</param> |U;w !0
<result gJWlWVeq$
Mqrt-VPh
name="success">/user/user_list.jsp</result> }'@tA")-)
</action> *#X+Gngo
I v 80,hW
</package> z|t.y.JX
;j[q?^ b
</xwork> 7)ES!C
:X1`wBu
xEd#~`Jmr
mI{CM:
:
\t&n
jMWpZ
0lvb{Zd
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 R 47I\{
LH?gJ8`
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。 oT9XJwqnv
C9"f6>i
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 UgOGBj,&5W
pn ~/!y
HQ-N!pf9
];YglHH
]ly)z[is"]
我写的一个用于分页的类,用了泛型了,hoho xc3Ov9`8%
%j
9vX$Hj
java代码: W#oEF/G
;DT"S{"7
>o=axZNa
package com.intokr.util; (_s!,QUe
D9@<#2-
import java.util.List; ~@a) E+LsF
W2X+NacD
/** }[hDg6i
* 用于分页的类<br> DbPBgD>Q
* 可以用于传递查询的结果也可以用于传送查询的参数<br> r&j+; JM5
* iG;d0>Sp
* @version 0.01 9I^H)~S
* @author cheng S%a}ip&
*/ 9v5.4a}
public class Paginator<E> { x r+E
privateint count = 0; // 总记录数 A7I8Z6&
privateint p = 1; // 页编号 7@e[:>e
privateint num = 20; // 每页的记录数 U3VsMV*Y
privateList<E> results = null; // 结果 N?`GZ+5
//4p1^%
/** 52q!zx E
* 结果总数 q(${jz4w
*/ K7d1(.
publicint getCount(){ HeAc(_=C
return count; `siy!R
} $)i"[
Si%Eimiq
publicvoid setCount(int count){ FrE/K_L
this.count = count; i >/@]2
} st1M.}
r(/P||`l
/** :u|UVp5
* 本结果所在的页码,从1开始 *SAcH_I2$>
* 2-B8>-
* @return Returns the pageNo. 37<GG)
*/ % 'L=
publicint getP(){ KlSY^(kHR
return p; swe8
} 'DB({s
ZeDDH
/** H]]>sE
* if(p<=0) p=1 `(w kqa
* %CfTqbB
* @param p _tg3%X]
*/ 8mQd*GGu1
publicvoid setP(int p){ 2[bR6 T89
if(p <= 0) hF{mm(qyv
p = 1; EZNB`gO
this.p = p; 8)Bn?6.
} s#8{:ko
xX67bswG
/** {3yws4
* 每页记录数量 0^tJX1L
*/ 5tbiNm^X
publicint getNum(){ 4 9+}OIX
return num; 70 DQ/b
} C8%nBa/
8i+jFSZ$
/** NIcNL(]
* if(num<1) num=1 3ks|
*/ hc~#l #
publicvoid setNum(int num){ +\]S<T*;
if(num < 1) tZ6v@W
num = 1; !&<Wc^PG
this.num = num; F^[Rwzv>c
} Ub-k<]yZ
9R<J$e
/** ,HjHt\!~<
* 获得总页数 Z{>Y':\?<
*/ z8MpE
publicint getPageNum(){ -ZMl[;OM
return(count - 1) / num + 1; <H(AS'
} #
v/aI*Rl
Pp" )hFx
/** Szob_IEq,
* 获得本页的开始编号,为 (p-1)*num+1 RI].LB_
*/ Tr+Y@]"
publicint getStart(){ os0"haOI9h
return(p - 1) * num + 1; 'G
By^hj?
} k1
txY
i2 Iu2
/** sZ(Q4)r
* @return Returns the results. ?_`P;}4#
*/ n ;fTx
publicList<E> getResults(){ .M#>@~XR
return results; Ymh2qGcj]8
} E!]rh,mYK
L&F\"q9q71
public void setResults(List<E> results){ ;@$, "
P
this.results = results; nHL>}Yg
} >!WBlSy
u K &_IE}
public String toString(){ N,'qMoNf
StringBuilder buff = new StringBuilder (]uoN4
;{#M
(); /t2<OU9
buff.append("{"); n@8{FoF
buff.append("count:").append(count); qv >(
buff.append(",p:").append(p); !!Gi.VL
buff.append(",nump:").append(num); vnT
buff.append(",results:").append G7#~=W
2M
xn#I7]]G
(results); -)c"cgx.
buff.append("}"); l<:)rg^,
return buff.toString(); eFI9S.6
} >WG91b<Xq
dJgOfg^
} GAe_Z(T
4zvU"np
F;l<>|vG