Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 uA[c$tBe
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 IgyoBfj\d
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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 s1>d)2lX
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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 aoHAB<.C
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分页支持类: <~teD[1k"
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java代码: s H(io
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package com.javaeye.common.util; 1k0*WCfZ
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import java.util.List; I~F]e|Ehqr
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publicclass PaginationSupport { g#%Egb1
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publicfinalstaticint PAGESIZE = 30; lx{ '
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privateint pageSize = PAGESIZE; E_D0Nm%n
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privateList items; 'm^]X3y*
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privateint totalCount; +z|@K=d#|
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privateint[] indexes = newint[0]; #h}a
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privateint startIndex = 0; yu}yON
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public PaginationSupport(List items, int 1]a\uq}
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totalCount){ 43,baeG
setPageSize(PAGESIZE); 7g>|e
setTotalCount(totalCount); h?Lp9VF
setItems(items); L/?jtF:o
setStartIndex(0); / ?'FSWDU
} 3Z}v%=5
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public PaginationSupport(List items, int \SN>Yy
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totalCount, int startIndex){ N4l}5(e
setPageSize(PAGESIZE); aTwBRm
setTotalCount(totalCount);
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setItems(items); *?pnTQs^
setStartIndex(startIndex); 88KQ) NU
} ^c]c`w
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public PaginationSupport(List items, int g(C/J9J
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totalCount, int pageSize, int startIndex){ H`s[=Y,m
setPageSize(pageSize); '#a;n
setTotalCount(totalCount); &$heW,
setItems(items); [jR>.H'
setStartIndex(startIndex); 0Ibe~!EiQJ
} op($+Q
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publicList getItems(){ uD\rmO{
return items; 3 MCV?"0
} ${e5Ka
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publicvoid setItems(List items){ 3BSZz%va
this.items = items; }wZsM[NDB
} :_|Xr'n`A
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publicint getPageSize(){ d&lT/S
return pageSize; Z*n4$?%W
} -/:!AxIH
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publicvoid setPageSize(int pageSize){ }.1}yz^y
this.pageSize = pageSize; Ept=&mJPu
} ^CK
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publicint getTotalCount(){ :F_>`{
return totalCount; '~VF*i^4
} rZ&li/Z
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publicvoid setTotalCount(int totalCount){ z31g"
if(totalCount > 0){ nRyx2\Py+
this.totalCount = totalCount; 6rM{r>
int count = totalCount / oB(9{6@N
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pageSize; c!GJS`/
if(totalCount % pageSize > 0) ^{YK'60
count++; {v"Y!/
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indexes = newint[count];
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for(int i = 0; i < count; i++){ e8M0Lz#}
indexes = pageSize * DVt^O[
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} 7m %[$X`
}else{ .Fx3WryF
this.totalCount = 0; 2FY]o~@
} =y >CO:^G%
} \Xe{vlo>h
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publicint[] getIndexes(){ T*g}^TEh
return indexes; $Wjx$fD
} $rJgBN
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publicvoid setIndexes(int[] indexes){ !DUOi4I
this.indexes = indexes; 3a&HW
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} _4T7Vg''
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publicint getStartIndex(){ =sso )/3
return startIndex; R?y_tho4A
} `dWnu3r;
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publicvoid setStartIndex(int startIndex){ P@Fx6
if(totalCount <= 0) QX42^]({;c
this.startIndex = 0; 2.^CIJc
elseif(startIndex >= totalCount) "YAnGGx)LZ
this.startIndex = indexes >*uj
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[indexes.length - 1]; O`I}Lg]~q
elseif(startIndex < 0) ~~O4!|t
this.startIndex = 0; ,fhF-%Q!g
else{ #guK&?Fye
this.startIndex = indexes "$P/ek
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[startIndex / pageSize]; I
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} pWn]$HaoG
} M& )yr^
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publicint getNextIndex(){ I2-ue 63 ?
int nextIndex = getStartIndex() + J*_^~t
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pageSize; Z|fi$2k0!
if(nextIndex >= totalCount) 0~P]Fw^w
return getStartIndex(); ;mg.} fI
else ]+b?J0|P<
return nextIndex; #K*p1}rf
} q#1G4l.
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publicint getPreviousIndex(){ s8'!1rHd
int previousIndex = getStartIndex() - R;fe v
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pageSize; fqBz"l>5A
if(previousIndex < 0) (XlvPcTi
return0; HH0ck(u_A*
else ?NvE9+n
return previousIndex; 0:-z+`RHE
} J1w3g,
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} C(UWir3mW?
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抽象业务类 &gW<v\6,
java代码: kd_!S[
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/** DC8\v+K
* Created on 2005-7-12 !&cfX/y8
*/ [k75+#'
package com.javaeye.common.business; yMzy!b Ky
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import java.io.Serializable; epG]$T![
import java.util.List; 1]Cbi7
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import org.hibernate.Criteria; wWSw0 H/
import org.hibernate.HibernateException; -m[ tYp,q
import org.hibernate.Session; xA<-'8ST
import org.hibernate.criterion.DetachedCriteria; IWm@pfC+g
import org.hibernate.criterion.Projections; h~qv_)F_
import [ w-Tf&
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org.springframework.orm.hibernate3.HibernateCallback; gPA8A>U)[
import LE~vSm^#
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org.springframework.orm.hibernate3.support.HibernateDaoS Q@8(e&{#W
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upport; /x]^Cqe
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import com.javaeye.common.util.PaginationSupport; ?"T!<L
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public abstract class AbstractManager extends $=#Lf[|f=
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HibernateDaoSupport { '4D7:
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privateboolean cacheQueries = false; d>T8V(Bb
/;:4$2R(;
privateString queryCacheRegion; Fe+(+ S
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publicvoid setCacheQueries(boolean MxUQ F?@6
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cacheQueries){ #%8)'=1+4?
this.cacheQueries = cacheQueries; L>&{<M_
} pAqPHD=
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publicvoid setQueryCacheRegion(String <AiE~l| D
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queryCacheRegion){ Ao*:$:k
this.queryCacheRegion = {.0I!oWv
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queryCacheRegion; 2^75|Q
} {?++T 0
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publicvoid save(finalObject entity){ &U CtyCz
getHibernateTemplate().save(entity); M?;YpaSe+
} 90,UhNz9D
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publicvoid persist(finalObject entity){ m6H+4@Z-;(
getHibernateTemplate().save(entity); @MoCEtt
} p&0 G
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publicvoid update(finalObject entity){ ;Xqi;EA
getHibernateTemplate().update(entity); `Fe/=]<$
} bD3 dT>(+
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publicvoid delete(finalObject entity){ I2NMn5>
getHibernateTemplate().delete(entity); [}
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} 9eE
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publicObject load(finalClass entity, a;kiAJ'
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finalSerializable id){ <Wj/A/
return getHibernateTemplate().load TEGg)\+D>
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(entity, id); \}<J>R@
} bE=[P}E
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publicObject get(finalClass entity, hOV5WO\
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finalSerializable id){ SOMAs'=
return getHibernateTemplate().get h/y0Q~|/d
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(entity, id); 7|bBC+;(
} F9(jx#J~t
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publicList findAll(finalClass entity){ a*_&[
return getHibernateTemplate().find("from O-pH~E
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" + entity.getName()); kp!(e0n
} !Htl e %
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publicList findByNamedQuery(finalString _5b~3K/V
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namedQuery){ J-G)mvkv
return getHibernateTemplate q1 BpE8
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().findByNamedQuery(namedQuery); ;NAKU
} o/vD]Fs
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publicList findByNamedQuery(finalString query, Q84XmXm|
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finalObject parameter){ _`laP5~
return getHibernateTemplate .vIRz-S
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().findByNamedQuery(query, parameter); vfVF^
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} '%rn-|)
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publicList findByNamedQuery(finalString query, .lI.I
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finalObject[] parameters){ xk,1D
return getHibernateTemplate !:uh? RW
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().findByNamedQuery(query, parameters); B4c;/W-
} l Dwq[ I]w
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publicList find(finalString query){ 8{7'w|/;.{
return getHibernateTemplate().find Q&PEO%/D
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(query); m1tc="j
} hu}uc&N)iE
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publicList find(finalString query, finalObject @00&J~D
)U0I|dx
parameter){ 5l(@p7_+
return getHibernateTemplate().find ~X'hRNFx~
(9] =;)
(query, parameter); $%ztP
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} D*_.4I
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public PaginationSupport findPageByCriteria /R(
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(final DetachedCriteria detachedCriteria){ NjdDImz.;s
return findPageByCriteria 1pN8,[hyR7
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); MQy,[y7I
} `V*$pHo
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public PaginationSupport findPageByCriteria =~dXP
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(final DetachedCriteria detachedCriteria, finalint g`"_+x'
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startIndex){ /
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return findPageByCriteria C
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(detachedCriteria, PaginationSupport.PAGESIZE, lZ`@ }^&
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startIndex); / >7G
} UVsF !0
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public PaginationSupport findPageByCriteria Oe k$f,J-
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(final DetachedCriteria detachedCriteria, finalint `#j;\
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pageSize, y99|V39'
finalint startIndex){ Xcg+ SOB
return(PaginationSupport) Xupwh5G2
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getHibernateTemplate().execute(new HibernateCallback(){ Dkg-y9
publicObject doInHibernate 3Z%jx#
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(Session session)throws HibernateException { K#yCZ2
Criteria criteria = zWF[cf>'
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detachedCriteria.getExecutableCriteria(session); 8Urj;KkD
int totalCount = S;nlC
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((Integer) criteria.setProjection(Projections.rowCount C33RXt$X
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()).uniqueResult()).intValue(); 0!1cHB/c
criteria.setProjection I5rAL\ y-G
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(null); KM-7w66V
List items = XIp>PcU^
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criteria.setFirstResult(startIndex).setMaxResults ksAu=X:
njb{
(pageSize).list(); "?"+1S
PaginationSupport ps = L@G~9{U>
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new PaginationSupport(items, totalCount, pageSize, AUr~b3< 6
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startIndex); difAQ<`
return ps; {9nH#yv
} QnIF{TS=
}, true); e:|Bn>*
} ):5H,B+Vr&
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public List findAllByCriteria(final n55s7wzM
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DetachedCriteria detachedCriteria){ H4ancmy
return(List) getHibernateTemplate $~1~+s0$
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().execute(new HibernateCallback(){ $# J
publicObject doInHibernate @$o^(my
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(Session session)throws HibernateException { y,$zSPJCi
Criteria criteria = iE"+-z\U
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detachedCriteria.getExecutableCriteria(session); '77Gg
return criteria.list(); TK Ec^
} l3YS_WBSn
}, true); ?T8^tGD[
} -1]8f
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public int getCountByCriteria(final %I%OHs
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DetachedCriteria detachedCriteria){ qW9~S0sl
Integer count = (Integer) B>e},!
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getHibernateTemplate().execute(new HibernateCallback(){ '2S?4Z
publicObject doInHibernate p</V_BIW
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(Session session)throws HibernateException { 1&utf0TX6q
Criteria criteria = .J2tm2]"EZ
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detachedCriteria.getExecutableCriteria(session); }r;#|=HR
return zdN(r<m9"
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criteria.setProjection(Projections.rowCount Uk0
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()).uniqueResult(); N7dI}ju
} kaNK@a=e|/
}, true); rSNaflYAr
return count.intValue(); RhSoD.Da
} [?VkwFD0
} QlH,-]N$L
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用户在web层构造查询条件detachedCriteria,和可选的 =~'{2gsB
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 q#P@,|nc:
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PaginationSupport的实例ps。 n~?n+\.&a
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ps.getItems()得到已分页好的结果集 G!5~`v
ps.getIndexes()得到分页索引的数组 Tu}?Q.pKo
ps.getTotalCount()得到总结果数 &K-0ld(;
ps.getStartIndex()当前分页索引 G[a&r
ps.getNextIndex()下一页索引 \@GKVssw
ps.getPreviousIndex()上一页索引 W=!di3IA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 rFG_CC2
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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 "\l#q$1h
asKAHVT(
一下代码重构了。 nlR7V.
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我把原本我的做法也提供出来供大家讨论吧: =4:]V\o):'
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首先,为了实现分页查询,我封装了一个Page类: 1'BC
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java代码: `z?h=&N
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/*Created on 2005-4-14*/ [IPXU9&Q
package org.flyware.util.page; 2#`9OLu8X
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/** +`'>
* @author Joa >4]y)df5
* [^eQGv[S
*/ @ACq:+/Qc
publicclass Page { zF#:Uc`C5U
SuFGIb7E
/** imply if the page has previous page */ ,!oR"b!
privateboolean hasPrePage; o$KW*aDp
fW3NH7aUG
/** imply if the page has next page */ >A ?,[p`<
privateboolean hasNextPage; )^LiALh
zT ; +akq
/** the number of every page */ ]T1\gv1~
privateint everyPage; )5/,B-+O"
UA(&_-C\
/** the total page number */ F`RPXY`ux
privateint totalPage; LV`tnt's
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/** the number of current page */ u/(~ewI
privateint currentPage; &^(4yw(~
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/** the begin index of the records by the current `tEW.s%Y(6
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query */ F8d:7`lO@/
privateint beginIndex; ] Wx?k7T
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/** The default constructor */ V&Q_iE
public Page(){ F6gU9=F1<
.r\|9 *j<
} /xw}]Fa5
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/** construct the page by everyPage nr- 32u
* @param everyPage :fA|J!^b[
* */ /<T3^/ '
public Page(int everyPage){ ^~JF7u
this.everyPage = everyPage; S$NJmXhx5
} {YF(6wVl
J*;= f8
/** The whole constructor */ 57[tUO
public Page(boolean hasPrePage, boolean hasNextPage, s%i
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int everyPage, int totalPage, |}isSCt
int currentPage, int beginIndex){ 0N`N
this.hasPrePage = hasPrePage; }}u16x}*n
this.hasNextPage = hasNextPage; k\KI#.>
this.everyPage = everyPage; +D
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this.totalPage = totalPage; A&D<}y/%
this.currentPage = currentPage; Czb:nyRj
this.beginIndex = beginIndex; V2>+s
y
} g<g$c<sm
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/** ob]j1gYb
* @return JiFB<Q\
* Returns the beginIndex. &.[I}KH|B
*/ *NCkC
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publicint getBeginIndex(){ ?ZP@H
_w6}
return beginIndex; tui5?\
} Hd57Iw
L'u*WHj|v
/** <HH\VG\H6
* @param beginIndex !24PJ\~I
* The beginIndex to set. /Csk"IfuO
*/ S9%ZeM+
publicvoid setBeginIndex(int beginIndex){ @K1'Q!S*
this.beginIndex = beginIndex; PC3?eS}
} lx:.9>
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/** :pvB}RYD
* @return =d#(n M*
* Returns the currentPage. [,sm]/Xlc
*/ jr/IU=u*v
publicint getCurrentPage(){ a g6[Nk
return currentPage; H @5dj}
} vOo-jUKs
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/** zx7A}rs3oX
* @param currentPage PwU<RKAE
* The currentPage to set. X8y :=k,E
*/ m2[]`Ir^@
publicvoid setCurrentPage(int currentPage){ 3 L:SJskYR
this.currentPage = currentPage; mwO9`AU;
} ujS C
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/** ){*9$486
* @return epgAfx-_OH
* Returns the everyPage. T'!p{Fbg;
*/ HutQx
publicint getEveryPage(){ 4Q:r83#
return everyPage; sGG
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} Cs2kbG_
lf#5X)V
/** =
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* @param everyPage jEn9T
* The everyPage to set. $bl<mG%#9
*/ -+[~eqRB
publicvoid setEveryPage(int everyPage){ >?[?W|k7V
this.everyPage = everyPage; F0tcVdv
} OV|n/~
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/** Zi{vEI ]
* @return U#:N/ts*(
* Returns the hasNextPage. X 4\V4_
*/ >dXB)yl
publicboolean getHasNextPage(){ (L`IL e*
return hasNextPage; UJ><B"
} o:`^1
`=%G&_3_<
/** PLq]\y
* @param hasNextPage =!u]t&yv
* The hasNextPage to set. |h& q
*/ +2>, -V
publicvoid setHasNextPage(boolean hasNextPage){ j\iNag(
this.hasNextPage = hasNextPage; ySHpN>U
} ^O<@I
Y>x3`f]
/** a]!u
go}
* @return .|@2Uf
* Returns the hasPrePage. duc\/S'
*/ Q-J} :U
publicboolean getHasPrePage(){ Q5]rc`}
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return hasPrePage; m[ER~]L/C
} +mN8uU~(kx
NfZC}
/** +xQj-r)-
* @param hasPrePage R)-~5"}~
* The hasPrePage to set. >0?ph<h1[q
*/ qv[w
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publicvoid setHasPrePage(boolean hasPrePage){ GJ:oUi
this.hasPrePage = hasPrePage; 2V*;=cv~z
} MAQ-'s@
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/** 5%+epzy
* @return Returns the totalPage. pm2]
* =3PZGdWD
*/ *ZIX76y<!A
publicint getTotalPage(){ nfh<3v|kvR
return totalPage; S[{,+{b0
} WBR# Ux
"n{JH9sA:
/** l!": s:/'
* @param totalPage t ?05
* The totalPage to set. 5"bg8hL
*/ [AYJ(H/
publicvoid setTotalPage(int totalPage){ &~'i,v|E
this.totalPage = totalPage; jQ8
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} y5 X FJj
#mD_<@@
} ?rziKT5OOC
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%vbov}R
_+Z5qUmQ
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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 goND S5}
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个PageUtil,负责对Page对象进行构造: kx;7/fH
java代码: ]Bs{9=2
9A87vs4[
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/*Created on 2005-4-14*/ R
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package org.flyware.util.page; di7cCn
kOC0d,
import org.apache.commons.logging.Log; )~`UDaj_
import org.apache.commons.logging.LogFactory; _Ud! tK*H
+pQ3bX
/** A)&CI6(
* @author Joa w|NI d,#f
* 0Qy L}y2
*/ )u0/s'
publicclass PageUtil { 4UND;I&
[;UI8Stw
privatestaticfinal Log logger = LogFactory.getLog GNSh`Tm =#
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(PageUtil.class); d^`;tD
C=2DxdZG
/** SiJ{
* Use the origin page to create a new page 7 0EH~
* @param page y1[@4TY]
* @param totalRecords S,Q(,e^&
* @return `fl$ o6S/
*/ 3Bcv"O,B!{
publicstatic Page createPage(Page page, int X$?0C{@.}
d(9-T@J
totalRecords){ 8"p rWAN
return createPage(page.getEveryPage(), |:,`dQfw
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page.getCurrentPage(), totalRecords); 4J?\JcGs
} /2MZH
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/** tY:,9eh7B
* the basic page utils not including exception HVzkS|^F
;= 1[D
handler 4UK>Vzn
* @param everyPage :Ys
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* @param currentPage X":2o|R
* @param totalRecords d=
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* @return page Z?WVSJUVf
*/ s(e1kk}"
publicstatic Page createPage(int everyPage, int p*Yx1er1
4n1 g@A=y
currentPage, int totalRecords){ t;u)_C,bmP
everyPage = getEveryPage(everyPage); `u_k?)lK
currentPage = getCurrentPage(currentPage); O}j@+p%M
int beginIndex = getBeginIndex(everyPage, 87m`K Str7
JY,oXA6O
currentPage); j?g#8L;W\w
int totalPage = getTotalPage(everyPage, QL2 `X2
"xn,'`a
totalRecords); S~&9DQNj
boolean hasNextPage = hasNextPage(currentPage, 8iM:ok
=kCiJ8q|
totalPage); }^P"R[+4u
boolean hasPrePage = hasPrePage(currentPage); KC%&or
yU"#2 *C
returnnew Page(hasPrePage, hasNextPage, @\M^Zuo
everyPage, totalPage, O@w_"TJP/z
currentPage, PWquu`
.u`A4;;Gw
beginIndex); {xOzxLB;
} }SyK)W5Y
kKY,&Fn-
privatestaticint getEveryPage(int everyPage){ LabI5+g
return everyPage == 0 ? 10 : everyPage; 3#GIZL}!x
}
*I}_g4
hS>=pO+y
privatestaticint getCurrentPage(int currentPage){
Qstd;qE~
return currentPage == 0 ? 1 : currentPage; ln":j?`
} @ScC32X
O1+yOef"k
privatestaticint getBeginIndex(int everyPage, int ;e9&WEG_\
+_QcLuV,
currentPage){ XQmg^x[,A
return(currentPage - 1) * everyPage; .[s6PzQy
} g@pK9R%wH<
1]vDM&9
privatestaticint getTotalPage(int everyPage, int Q'?VLv|@
$ f||!g
totalRecords){ f9+6gY
int totalPage = 0; madbl0[y.
|34w<0Pc,
if(totalRecords % everyPage == 0) {xTh!ih2-
totalPage = totalRecords / everyPage; wF59g38[z$
else |cC&,8O:{
totalPage = totalRecords / everyPage + 1 ; %b~ND?nn-
NzN"_o jM
return totalPage; Zv?"1Y< L
} y{~tMpo<
Q]/{6:C
privatestaticboolean hasPrePage(int currentPage){ %:Y(x$Qy
return currentPage == 1 ? false : true; %*V r}@BA)
} 5KIhk`S
lhf5[Rp
privatestaticboolean hasNextPage(int currentPage, l)'*jZ
sE!g!ht
int totalPage){ u
yE#EnsH
return currentPage == totalPage || totalPage == q-,`\
TS
jM-5aj[K
0 ? false : true; H
]!P[?
} ;lt8~ea
uD[T l
09{ s'
} U!E}(9
tb
2Uu!_n}tNF
KuL+~
2 OqEyXh
|$+/IxDP
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。 @=Dc(5`[
?ef7%0
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 yf-2E_yB
(T&(PCw|
做法如下: Ug4o2n0sk
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 1Tev&J
C~.T[Mlu
的信息,和一个结果集List: ZCMH?>
java代码: /x_AWnU
.RyuWh!5
^+k= ;nl
/*Created on 2005-6-13*/ `tXd?E/e
package com.adt.bo; %|>D{q6C
Q
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import java.util.List; 6#\:J0
u1d%wOY
import org.flyware.util.page.Page;
bf2r8
xVN!w\0
/** 3Wx\Liw,
* @author Joa C@<gCM j,"
*/ 6Ypc]ym=J
publicclass Result { ] ;CJ6gM~
_A0X[}^K
private Page page; z2!4w +2
%%)y4>I
private List content; A>HCX 4i
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/** }z|9F(I
* The default constructor N[v=;&
*/ %az6\"n
public Result(){ G)_Zls2;
super(); 1K R4Wq@
} c~OvoTF,
@D `j
/** H<P d&
* The constructor using fields hb
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* u,N<U t
* @param page ]1W]
* @param content "<%J^Z9G
*/ >$)~B4
public Result(Page page, List content){ =^_a2_BBl
this.page = page; G2+ gEg
this.content = content; zE?dQD^OD
} 2v#gCou
q:iu
hI$~G
/** UnEgsfN
* @return Returns the content. ` K0PLxSv
*/ U;"J8
publicList getContent(){ s#")hMJQ
return content; .b^!f<j
} >.G#\w
7u5H o`
/** 3f~znO
* @return Returns the page. ^62I 5k/u
*/ <U\8&Uv>
public Page getPage(){ NA`8 ^PZ
return page; g-NrxyTBlx
} ra_v+HR7
j'hWhLax
/** i
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* @param content OPogH=vf
* The content to set. rR#wbDr5
*/ sB^ejH
public void setContent(List content){ ?FV%e
this.content = content; A4b+:MQ*OX
} Nw-U*y
dy'lM ;@-
/** w|*D{`O
* @param page {LCKt/Z>P
* The page to set. x~{W(;`!
*/ N%1nii
publicvoid setPage(Page page){ UdA,.C0
this.page = page; oJ/=&c
} sBqOcy
} VwK7\jV
Ai5+ ;8z+
K\s<<dRa
-dfs8 [i
GMoz$c6n_
2. 编写业务逻辑接口,并实现它(UserManager, FP*kA_z$
FT-=^VA\
UserManagerImpl) }n'W0Sa
java代码: [
q[2\F?CE
,Tk53 "
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/*Created on 2005-7-15*/ NmF8BmIj
package com.adt.service; .f>7a;V?}
{eQijW2Z3
import net.sf.hibernate.HibernateException; lQm7`+
8LXK3D}?3
import org.flyware.util.page.Page; )V*`(dn'zm
uss!E!_%,
import com.adt.bo.Result; kf9]nIo
imhE=6{
/** l0g+OMt
* @author Joa bT|-G2g7Z
*/ +RkXe;q
publicinterface UserManager { YNKvR
WORRF
public Result listUser(Page page)throws [~`p~@\+
u),.q7(m
HibernateException; 5l%g3F
g@Y]$ey%A
} kVG+Wr7l0F
HnsLYY\
BqdpJIr
e+>$4Jq
%,aSD#l`f
java代码: x {Dw?6TP
'SrDc'?
4nh0bI N1
/*Created on 2005-7-15*/ HYY+Fv5
package com.adt.service.impl; Q|2*V1"r<2
^<
import java.util.List; *Gj`1#Z$
Ag8lI+
h
import net.sf.hibernate.HibernateException; 1Y~'U
=9
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import org.flyware.util.page.Page; C#3&,G W
import org.flyware.util.page.PageUtil; S?VKzVDB.S
2t>>08T
import com.adt.bo.Result; ~d ~oC$=TC
import com.adt.dao.UserDAO; B7oUS}M
import com.adt.exception.ObjectNotFoundException; 2=1qmQE
import com.adt.service.UserManager; kqq1;Kd
&h=f
/** lZ <D,&
* @author Joa w"O;: `|n
*/ 5~E{bW$
publicclass UserManagerImpl implements UserManager { Xr88I^F;
:&2%x
private UserDAO userDAO; 1Oak8 \G
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/** #yEkd2Vy{
* @param userDAO The userDAO to set. vu*9(t)EC
*/ [ lK`~MlQ
publicvoid setUserDAO(UserDAO userDAO){ K2V?[O#
this.userDAO = userDAO; t? =V<Yd1
} IMpL+W.
J{Ld)Q,^
/* (non-Javadoc) N.SV*G
@
* @see com.adt.service.UserManager#listUser b!nA.`T
mD*!<<Sw
(org.flyware.util.page.Page) P*hYh5a
*/ bQI.Qk
public Result listUser(Page page)throws w6^TwjjZ$
(Fq]y5
HibernateException, ObjectNotFoundException { oU*e=uehj
int totalRecords = userDAO.getUserCount(); Y ._Om}H
if(totalRecords == 0) -B-HZ_
throw new ObjectNotFoundException C]ax}P>BQ
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("userNotExist"); #]^M/y
h
page = PageUtil.createPage(page, totalRecords); s5MG#M 9
List users = userDAO.getUserByPage(page); 'RNj5r
returnnew Result(page, users); &lxMVynL
} LJt5?zQKrW
,">CPl]
} }wEt=zOJ
0G+qF96
N%u4uLP5k
_eH@G(W(
GSH,;cY
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 DQ0 UY
l}#d^S/
询,接下来编写UserDAO的代码: JxM32?Rm*w
3. UserDAO 和 UserDAOImpl: `/WOP`'zM
java代码: 2+R]q35-
uOZSX.o^
PMvm4<
/*Created on 2005-7-15*/ RL/5o"
package com.adt.dao; x_/H
2_Cp}Pj
import java.util.List; Lg2PP#r
WW7E*kc
import org.flyware.util.page.Page; oB'5':
th0>u.hJ
import net.sf.hibernate.HibernateException; >km$zfM2-
pNu?DF{
3
/** ,I,Zl.5
* @author Joa [g+WL\1
*/ =OKUSHu@V
publicinterface UserDAO extends BaseDAO { L%pAEoSG
7&L8zl|K
publicList getUserByName(String name)throws ?;w\CS^Qu
&iy7It
HibernateException; 5D3&6DCH
M[_Ptqjb
publicint getUserCount()throws HibernateException; yC!>7@m
I Qmlmu
publicList getUserByPage(Page page)throws piIGSC
(?.h<v1}
HibernateException; EvA8<o
" ;\EU4R
} +hH7|:JQ
&@PAv5iNf
n~i^+pD@
;B:\e8
.l,NmF9
java代码: *_ajb:
1D~B\=LL}
'w|N}
4
/*Created on 2005-7-15*/ M?['HoRo
package com.adt.dao.impl; s(MdjWw
90H/Txq
import java.util.List; ;BHIss7
\z.p [;'ir
import org.flyware.util.page.Page; |I.5]r-EK
GB6(WAmr
import net.sf.hibernate.HibernateException; +>%AG&Pc
import net.sf.hibernate.Query; s:tWEgZk?
_e|-O>#pl
import com.adt.dao.UserDAO; /5\{(=0
P rv=f@
/** clIn}wQ
* @author Joa X{h[
*/ I7<UC{Ny
public class UserDAOImpl extends BaseDAOHibernateImpl ;N
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9HlM0qE5b
implements UserDAO { M IU B]
;;EFiaA
/* (non-Javadoc) owO&[D/
* @see com.adt.dao.UserDAO#getUserByName FGpV
]p
J]Q-#g'Z
(java.lang.String) h?GE-F
*/ 2k`Q+[?{q>
publicList getUserByName(String name)throws j?!/#'
dmMrZ1u2
HibernateException { gLbTZM4i
String querySentence = "FROM user in class )_Iu7b
?.nD!S@
com.adt.po.User WHERE user.name=:name"; _Vr}ipx-k
Query query = getSession().createQuery uU+?:C
!B#tJD
(querySentence); UXHtmi|_:
query.setParameter("name", name); P;ZVv{mT
return query.list(); Vz y )jf
} 3tmS/tQp
GbC JGqOR
/* (non-Javadoc) }5QUIK~NA
* @see com.adt.dao.UserDAO#getUserCount() U(<~("ocN
*/ W:2j.K9!
publicint getUserCount()throws HibernateException { 1.a:iweN
int count = 0; tA
K=W$r
String querySentence = "SELECT count(*) FROM :,'.b|Tl.b
U
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user in class com.adt.po.User"; c{i\F D
Query query = getSession().createQuery q6P5:@
D:N\K/p
(querySentence); pEb/ yIT"
count = ((Integer)query.iterate().next T<mP.T,$!
*o=( w5
()).intValue(); M7(]NQ\TQ
return count; @^b>S6d"
} m;u :_4
\YH*x`
/* (non-Javadoc) w|ct="MG
* @see com.adt.dao.UserDAO#getUserByPage <I2~>x5db
v0%FG9Gk
(org.flyware.util.page.Page) 7+P-MT
*/ 08nA}+k
publicList getUserByPage(Page page)throws b.xG'
//^{u[lr
HibernateException { /J&_ZDNV~
String querySentence = "FROM user in class {=P}c:iW
iDlg>UYd
com.adt.po.User"; q9(hn_X@/
Query query = getSession().createQuery 1_)Y{3L
|eej}G(,m}
(querySentence); sTi3x)#xB
query.setFirstResult(page.getBeginIndex()) #-g2p?+i&
.setMaxResults(page.getEveryPage()); V:1_k"zQ
return query.list(); :U'Oc3l#Y
} c+UZ UgP
~fz9PoC
} m=MM
stOD5yi
)oMMDHw\
i0[mU,
3O?[Yhk`.
至此,一个完整的分页程序完成。前台的只需要调用 XC[bEp$
-p20UP 1I
userManager.listUser(page)即可得到一个Page对象和结果集对象 v
<E#`4{
V}q=!zz
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;QQ/bM&I
sW@_q8lG
webwork,甚至可以直接在配置文件中指定。 xGK"`\V
C*Dco{
EQ>
下面给出一个webwork调用示例: 8s6^!e&
java代码: o 0H.DeP
C.hRL4+;Zm
JE[J}-2
/*Created on 2005-6-17*/ X@@7Qk
package com.adt.action.user; (.9H1aO46|
jp#/]>(9Z
import java.util.List; fZ pUnc
B..> *Xb
import org.apache.commons.logging.Log; zR }vw{
import org.apache.commons.logging.LogFactory; @}A3ie'w
import org.flyware.util.page.Page; lFc^y
@)3orH
import com.adt.bo.Result; ~@'DYZb-
H
import com.adt.service.UserService; jN sM&s,
import com.opensymphony.xwork.Action; w#RfD
gPy}.g{tH$
/** !F#^Peb
* @author Joa e `IL7$
*/ &=v5M9GR]
publicclass ListUser implementsAction{ ;C+
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4 _Idf
privatestaticfinal Log logger = LogFactory.getLog u!I=|1s
AF"XsEt.e
(ListUser.class); W^1)70<y
8,?*eYNjb
private UserService userService; QQX7p!~E
{3\{aZ8)
private Page page; a O(&<
|=s jGf
privateList users; b@)nB
#e$vv!&}
/* *uvE`4V^Jg
* (non-Javadoc) ]0myoWpi3
* 4d
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* @see com.opensymphony.xwork.Action#execute() @s~*>k#"#
*/ v^1n.l %E
publicString execute()throwsException{ 4XArpKA
Result result = userService.listUser(page); u$y5?n|
page = result.getPage(); lgh+\pj
users = result.getContent(); 3b1%^@,ACy
return SUCCESS; p|'Rm]&jb
} pL{:8Ed
5s1XO*s)>X
/** ^%m~V LH
* @return Returns the page. jo[U6t+pj7
*/ D
P+W*87J
public Page getPage(){ '8UhYwyr
return page; to;cF6X
} d8/KTl
(KdP^.7
/** D>"!7+t|@a
* @return Returns the users. NLO&.Q]#
*/ MGSD;Lgn
publicList getUsers(){ 0`"DYJ}d
return users; RV, cQ K
} SI/p8 ^
;F\sMf{
/** j+NpQ}t:
* @param page qwHP8GU
* The page to set. [35>T3Ku
*/ 'V(9ein^Q
publicvoid setPage(Page page){ xs$-^FnD
this.page = page; 5q{
-RJ
} ~`o%Y"p%rv
5tm:|.`SQ
/** E#mpj~{-
* @param users qre(3,VE5
* The users to set. IyGW>g6_.
*/ khfWU
publicvoid setUsers(List users){ oD~q/04!
this.users = users; $1;@@LSw
} 9Gk#2
-v62 s
/** '7>Yrzq
* @param userService OiMr,
* The userService to set. zr[|~-
*/ DO9_o9'
publicvoid setUserService(UserService userService){ |bv7N@?e
this.userService = userService; \-R\xL
} Z6_E/S
} L QA6iZBP
AWz|HF#-
yVb yw(gS
JD{AwE@Ro
P/doNv}iG
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, zc%HBZ3p
F`JW&r\
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 t
gHXIr}3
G;v3kGn
么只需要: #EX NS r
java代码: 2qfKDZ9f^
v!%VH?cA8
#kPsg9Y
<?xml version="1.0"?> @w@ `-1
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork $z'_Hr'
\6K1Z!*;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- L|K^w *\C
9:]|TIPi
1.0.dtd"> _$BH.I
Ej/P:nB
<xwork> *K2fp=Ns
8Xk,Nbcqt
<package name="user" extends="webwork- qBXIR}
yc3i> w`
interceptors"> 8VR!
Y0`e
hR%2[lBn!]
<!-- The default interceptor stack name 3[}w#n1
)SsO,E+t=U
--> #FsoK*F
<default-interceptor-ref LQ.0"6oj
b?%Pa\,!
name="myDefaultWebStack"/> /^9yncG;>
P'D'+qS
<action name="listUser" %~^:[@xa*
'w~e>$WI
class="com.adt.action.user.ListUser"> BF+i82$zo
<param 8c0ugM
[Cf{2WB:7
name="page.everyPage">10</param> ck K9@RQ
<result XCQPVSh
l6k.`1.In
name="success">/user/user_list.jsp</result> N2e]S8-
</action> P~ 7p~ke
uT2w2A;
</package> `Uy'YfYF
&Y|AX2KUC
</xwork> /F7X"_(H
+U*:WKdI?
fD ?w!7f-1
D}A>`6W<