Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 n}Z%-w$K#
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }uMu8)Q
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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 OF*E1BM
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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 $E[O}+L$#
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分页支持类: }'vQUGu8z
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java代码: <!t;[ie?y
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package com.javaeye.common.util; kDJYEI9j>
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import java.util.List; ?6*\M
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publicclass PaginationSupport { 1?)h-aN
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; uLv
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privateList items; R1hmJ
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privateint totalCount; kK6t|Yn&
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privateint[] indexes = newint[0]; 1WaQWZ:=
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privateint startIndex = 0; q !}~c
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public PaginationSupport(List items, int R,.qQF\*
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totalCount){ lw8t#_P
setPageSize(PAGESIZE); M.SF}U
setTotalCount(totalCount); @=g{4(zR^
setItems(items); DCa=o
setStartIndex(0); ;]R5:LbXS
} KKk<wya&O
Y A+R!t:F{
public PaginationSupport(List items, int d?5oJ'JU
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totalCount, int startIndex){ ;|\j][A
setPageSize(PAGESIZE); nIOSP:'>
setTotalCount(totalCount); ~W"@[*6w
setItems(items); `<@ "WSn
setStartIndex(startIndex); Z
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} <zAYq=IU
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public PaginationSupport(List items, int {:Kr't<XzF
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totalCount, int pageSize, int startIndex){ |WOc0M[U
setPageSize(pageSize); &H+n0v
setTotalCount(totalCount); H4sc7-
setItems(items); {lgiH+:
setStartIndex(startIndex); U;!J(Us
} dT (i*E\j
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publicList getItems(){ $2-_j)+
return items; i` ay9J8N
} l/\D0\x2
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publicvoid setItems(List items){ $ \o)-3
this.items = items; JZ&_1~Z=
} S_;r!.
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publicint getPageSize(){ sH >zsc
return pageSize; xH}bX- m
} -~X[j2
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publicvoid setPageSize(int pageSize){ A5%$<
this.pageSize = pageSize; x($Djx
} Xkg
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publicint getTotalCount(){ HPJHA ,
return totalCount;
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} x;Slv(|M
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publicvoid setTotalCount(int totalCount){ _mwt{D2r}
if(totalCount > 0){ z0 #2?o
this.totalCount = totalCount; 5NH4C
int count = totalCount / ItZYOt|Hn
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pageSize; 3wcFR0f
if(totalCount % pageSize > 0) 6]kBG?m0
count++;
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indexes = newint[count]; Y:, rN
for(int i = 0; i < count; i++){ dM P'Vnfj
indexes = pageSize * a7453s
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} ^NRf
}else{ Au}l^&,zN
this.totalCount = 0; (Cfb8\~
} tMp!MQ
} n|XheG7:
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publicint[] getIndexes(){ 5gqs"trF
return indexes; n+te5_F
} ~1[n@{*: (
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publicvoid setIndexes(int[] indexes){ #8yo9g6
this.indexes = indexes; 8T6NG!/
} V[K N,o{6
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publicint getStartIndex(){ D&D6!jz
return startIndex; |?8nO.C~V
} <r$h =hM
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publicvoid setStartIndex(int startIndex){ QuPz'Ut#
if(totalCount <= 0) oW6Hufu+o
this.startIndex = 0; V-n{=8s
elseif(startIndex >= totalCount) V|$PO
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this.startIndex = indexes !*NDsC9
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[indexes.length - 1]; |%v:>XEO
elseif(startIndex < 0) d(d<@cB9
this.startIndex = 0; C49\'1\6
else{ c {%mi
this.startIndex = indexes tm^joK[{|J
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[startIndex / pageSize]; 3mo4;F,h9
} MK)}zjw
} aaT3-][
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publicint getNextIndex(){ kaB|+U9^
int nextIndex = getStartIndex() + ]0ErT9
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pageSize; 3WGE T[3
if(nextIndex >= totalCount) GyN|beou
return getStartIndex(); <TtPwUX
else 6{=U=
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return nextIndex; `?(J(H
} A%Ka)UU+n
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publicint getPreviousIndex(){ v#%rjml[
int previousIndex = getStartIndex() - e,_Sj(R8
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pageSize; Jcze.t
if(previousIndex < 0) ofQs
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return0; N'WTIM3W
else ISs&1`Y
return previousIndex; KYm8|]'g
} DX>LB$dy?
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} D!,5j_,j%
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抽象业务类 ;P)oKx
java代码: scH61Y8`
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/** z:f&k}(
* Created on 2005-7-12 =|1_6.tz
*/ 9m$"B*&6G
package com.javaeye.common.business; M11\Di1
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import java.io.Serializable; {L7Pha
import java.util.List; m_/Ut
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import org.hibernate.Criteria; }? / Blr
import org.hibernate.HibernateException; by
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import org.hibernate.Session; giNXXjl
import org.hibernate.criterion.DetachedCriteria; GuR^L@+ -.
import org.hibernate.criterion.Projections; hb3:,c(
import wz`% (\
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org.springframework.orm.hibernate3.HibernateCallback; 8)9-*Bzj
import m)p|NdTZc8
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org.springframework.orm.hibernate3.support.HibernateDaoS >B0AJW/u
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upport; M@{?#MkS%
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import com.javaeye.common.util.PaginationSupport; 9lYfII}4(
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public abstract class AbstractManager extends (7G4 v
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HibernateDaoSupport { b&[".ibN1
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privateboolean cacheQueries = false; WBWW7 HK
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privateString queryCacheRegion; S3%2T
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publicvoid setCacheQueries(boolean Qa=Y?=Za
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cacheQueries){ ; H ;h[
this.cacheQueries = cacheQueries; ]`$yY5 &W0
} $}WT"K
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publicvoid setQueryCacheRegion(String HN5661;8
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queryCacheRegion){ _|M8xI
this.queryCacheRegion = HZ'rM5Kq
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queryCacheRegion; 9k;,WU(K<
} sn:VM HrOT
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publicvoid save(finalObject entity){ N0S^{j,i
getHibernateTemplate().save(entity); _"
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} eB#I-eD
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publicvoid persist(finalObject entity){ LnE/62){N
getHibernateTemplate().save(entity); h_ 4*?w
} u1X^#K$nu'
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publicvoid update(finalObject entity){ .@)vJtH)
getHibernateTemplate().update(entity); 4:rwzRDY
} i+O7," (@
.*`^dt
publicvoid delete(finalObject entity){ -/?)0E
getHibernateTemplate().delete(entity); `$> Y
} 'EIe5Op
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publicObject load(finalClass entity, f\oW<2k]~
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finalSerializable id){ 7vZO;FGtG
return getHibernateTemplate().load kZG=C6a
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(entity, id); B<EqzP*#
} ;av!fK
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publicObject get(finalClass entity, EmT_T3v
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finalSerializable id){ 7<WUjK|
return getHibernateTemplate().get t4UK~ {gh
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(entity, id); cVx SO`jZw
} GwF8ze+cH
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publicList findAll(finalClass entity){ `l]Lvk8O
return getHibernateTemplate().find("from !Np7mv\7
lUjZ=3"'
" + entity.getName()); o;6~pw%
} &UH0Tw4
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publicList findByNamedQuery(finalString k9*UBx
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namedQuery){ .pPuBJL]<
return getHibernateTemplate ?S&
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().findByNamedQuery(namedQuery); _}[WX[Le{
} #EUT"^:d
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publicList findByNamedQuery(finalString query, {,5.svO
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finalObject parameter){ Ry}4MEq]
return getHibernateTemplate c&bhb[
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().findByNamedQuery(query, parameter); f4pIF"U9>
} "Q+wO+}6
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publicList findByNamedQuery(finalString query, qery|0W
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finalObject[] parameters){ HYO/]\al
return getHibernateTemplate 3M?O(oO
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().findByNamedQuery(query, parameters); e+!xy&u@u
} 07>m*1G
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publicList find(finalString query){ mg:kVS
return getHibernateTemplate().find (&79}IEd
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(query); \y271}'
} 5D<Zbn.>q
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publicList find(finalString query, finalObject Qa/1*Mb
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parameter){ |in>`:qk
return getHibernateTemplate().find *\#<2 QAe
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(query, parameter); R%r25_8
} 7_3
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public PaginationSupport findPageByCriteria E8PwA.
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(final DetachedCriteria detachedCriteria){ D"$ 97
return findPageByCriteria :I"22EH
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); eK(k;$4\^Y
} S=S/]]e
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public PaginationSupport findPageByCriteria e~*tQ4
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(final DetachedCriteria detachedCriteria, finalint 19[o XyFI
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startIndex){ wvisu\V
return findPageByCriteria d]K8*a%[-
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(detachedCriteria, PaginationSupport.PAGESIZE, ~G8l1dD
}LS.bQKqi,
startIndex); cV1E<CM
} A`~?2LH,~F
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public PaginationSupport findPageByCriteria s^6,"C
)(.g~Q:
(final DetachedCriteria detachedCriteria, finalint Y5ei:r|^
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pageSize, L$"x*2[A
finalint startIndex){ y+$vHnS/jC
return(PaginationSupport) [oBRH]9cq
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getHibernateTemplate().execute(new HibernateCallback(){ 0n4( Rj|}2
publicObject doInHibernate ?HOnDw.v1
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(Session session)throws HibernateException { H/ e jO_{
Criteria criteria = [giw(4m#y
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detachedCriteria.getExecutableCriteria(session); m@I}$
int totalCount = p|qLr9\A
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((Integer) criteria.setProjection(Projections.rowCount 9X1vL
(6H7?nv
()).uniqueResult()).intValue(); W:j9 KhvT
criteria.setProjection "p+oi@
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(null); vd^Z^cpip
List items = s)3CosU
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criteria.setFirstResult(startIndex).setMaxResults o&k,aCQC
.*595SuF
(pageSize).list(); Zn*W2s^^{
PaginationSupport ps = qKeR}&b
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new PaginationSupport(items, totalCount, pageSize, RxPD44jVA
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startIndex); o9Mr7
return ps; 9P#kV@%(0c
} 3*7 klu
}, true); j~+(#|
} N`X|z
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public List findAllByCriteria(final G:|]w,^i
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DetachedCriteria detachedCriteria){ >#T?]5Z'MF
return(List) getHibernateTemplate ?mVSc/
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().execute(new HibernateCallback(){ +uNMyVH
publicObject doInHibernate nemC-4}
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(Session session)throws HibernateException { g38MF
Criteria criteria = Mbly-l{|
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detachedCriteria.getExecutableCriteria(session); eAQ-r\h'2
return criteria.list(); ^x(s!4d]
} YiL^KK
}, true); 3RlNEc%)
} EuVA"~PA
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public int getCountByCriteria(final Az?^4 1r8
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DetachedCriteria detachedCriteria){ xA*6Z)Y
Integer count = (Integer) 7coVl$_Zl
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getHibernateTemplate().execute(new HibernateCallback(){ ka`}lR
publicObject doInHibernate NOAz"m+o
}-Nc}%5
(Session session)throws HibernateException { ~xJr|_,gp
Criteria criteria = p gv, Su
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detachedCriteria.getExecutableCriteria(session); 0uGTc[^^M
return QPFv]^s(
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criteria.setProjection(Projections.rowCount 4^ 0CHy
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()).uniqueResult(); Cf
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} m.5@qmQ
}, true); SapVS*yx@
return count.intValue(); )2jH&}K
} W:}t%agis
} e?GzvM'2
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用户在web层构造查询条件detachedCriteria,和可选的 }n,LvA@[0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {XnBj}C
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PaginationSupport的实例ps。 A'n7u'6=
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ps.getItems()得到已分页好的结果集 _?Ly7*UML
ps.getIndexes()得到分页索引的数组 ki?V
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ps.getTotalCount()得到总结果数 S}
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ps.getStartIndex()当前分页索引 BY$L[U;@T
ps.getNextIndex()下一页索引 9S5C{~P4
ps.getPreviousIndex()上一页索引 7G Jhc
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 NMN&mJsmh
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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*{E-m/
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一下代码重构了。 r;"Qu
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我把原本我的做法也提供出来供大家讨论吧: _6aI>b#yL
C&.Q|S2_
首先,为了实现分页查询,我封装了一个Page类: <CS,v)4,nH
java代码: QghL=
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/*Created on 2005-4-14*/ | tFg9RT
package org.flyware.util.page; xr^fP~V|)0
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/** @M(+YCi:e@
* @author Joa 7K24sHw;%
* aM\Ph&c7e'
*/ X9YbTN
publicclass Page { yM? jiy
r
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/** imply if the page has previous page */ 2KNs,4X@
privateboolean hasPrePage; I\=&v^]
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/** imply if the page has next page */ kM76?M
privateboolean hasNextPage; 8y]{I^z}
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/** the number of every page */ zy8D&7Ytf
privateint everyPage; ~AcjB(
lt{"N'Gw6
/** the total page number */ p'=XW#2 >
privateint totalPage; ]!WD">d:
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/** the number of current page */ OB+QVYk"
privateint currentPage; w(q\75
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/** the begin index of the records by the current cXt]55"
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query */ o^x,JT
privateint beginIndex; 9gETWz(3I
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/** The default constructor */ b2hXFwPe
public Page(){ W"5VqN6v
W;.LN<bx
} ]KQBek#DD
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/** construct the page by everyPage eMU t%zvb
* @param everyPage E&\ 0+-Dw
* */ Mu$"fYKf"
public Page(int everyPage){ lR5k1J1n
this.everyPage = everyPage; o#V{mm,{Pm
} 1*OZu.NdK
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/** The whole constructor */ Jy-V\.N>s
public Page(boolean hasPrePage, boolean hasNextPage, et@<MU@`
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int everyPage, int totalPage, +3r4GEa
Z
int currentPage, int beginIndex){ {0\9HI@
this.hasPrePage = hasPrePage; ~lr,}K,
this.hasNextPage = hasNextPage; DP!~WkU~
this.everyPage = everyPage; i0&W}Bb'
this.totalPage = totalPage; Jmun^Q/h
this.currentPage = currentPage; \mNN ) K@
this.beginIndex = beginIndex; ;~n^/D2.
} B5!|L)7>{p
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/** {w<"jw&2
* @return g
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* Returns the beginIndex. ulNMqz\.
*/ Ev0=m;@_
publicint getBeginIndex(){ "_n})s
f
return beginIndex; 9QEK|x`8
} *Jg&:(#}<J
)^j62uv
/** J(Zz^$8]<?
* @param beginIndex U,Z7nH3_
* The beginIndex to set. Z8\/Fb
*/ C\}M_MD
publicvoid setBeginIndex(int beginIndex){ \ 9#X]H
this.beginIndex = beginIndex; 1i;#cIG
} af}JS2=$
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w%v
/** 'oF ('uR
* @return PySFhb@
* Returns the currentPage. )Qh*@=$-
*/ =s,}@iqNO4
publicint getCurrentPage(){ O-qpB;|
return currentPage; x,TnYqT^
} !3 zN [@w,
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/** Sgn<=8,6c
* @param currentPage aA'of>'ib|
* The currentPage to set. b8|<O:]Hp
*/ a( SJ5t?-2
publicvoid setCurrentPage(int currentPage){ Qn)AS1pL+
this.currentPage = currentPage; yBfX4aH:`
} /&zlC{:G92
@nIoIz
D~
/** K<MWiB&
* @return gB]jLe
* Returns the everyPage. UHBMl>~z
*/ - #-Bo
publicint getEveryPage(){ bmO(tQS$5
return everyPage; 5 TLE%#G@+
} X}`39r.
Ht|"91ZC5
/** {TaYkuWS
* @param everyPage >{>X.I~
* The everyPage to set. 5.
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*/ H/ar:j
publicvoid setEveryPage(int everyPage){ O"J"H2}S
this.everyPage = everyPage; Wjr^: d
} r(JP&
@
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/** h;):TFiC
* @return |BXp `
* Returns the hasNextPage. g-4ab|F
*/ ubMN
publicboolean getHasNextPage(){ A[m<xtm5K
return hasNextPage; V,]Fh5f
} hp@F\9j
~Gl5O`w(
/** ~U5Tn3'~
* @param hasNextPage z=Xh
* The hasNextPage to set. ha7mXGN%
*/ B_>r|^Vh
publicvoid setHasNextPage(boolean hasNextPage){ 2?:'p[z"]
this.hasNextPage = hasNextPage; 4K*st8+bl-
} YKzfI9Y
,\N4tG1\
/** TSVlZy~Xo
* @return dFmpx%+p
* Returns the hasPrePage. wLNkXC
*/ m[Mw2 F
publicboolean getHasPrePage(){ yT[=!M
return hasPrePage; tJA"BP3f
} uzhTNf
Z+=-)&L
/** wj5,_d)
* @param hasPrePage IkO[R1K
* The hasPrePage to set. a)I>Ns)
*/ KNR7Igw?}
publicvoid setHasPrePage(boolean hasPrePage){ ppGWh
this.hasPrePage = hasPrePage; J"$U$.W=
} PcjeuJZ
.o]9
HbIk5
/** b1QHZY\g{
* @return Returns the totalPage. =Aw`0
* ?Ezy0>j
*/ _&S;*?K.
publicint getTotalPage(){ Rtlc&Q.b
return totalPage; HE>V\+
AL
} #^(Yw|/K
5rmQ:8_5
/** h6n!"z8H
* @param totalPage `gyke2n
* The totalPage to set. :jC$$oC].
*/ xxwbX6^d
publicvoid setTotalPage(int totalPage){ f4&;l|R0a
this.totalPage = totalPage; |<O^M q
} 7P]i|Q{
Y#6LNI
} yr?X.Np
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z?F`)}
C](djkA$
a*iKpr- :
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 Mpco8b-b
btC6R>0
个PageUtil,负责对Page对象进行构造: 7U^{xDg.b
java代码: P1Eg%Y6
Q2:rWE{K!
O+/{[9s
/*Created on 2005-4-14*/ e/#6qCE
package org.flyware.util.page; v#`>
)rlkQ'DN
import org.apache.commons.logging.Log; ZkO2*;
import org.apache.commons.logging.LogFactory; 5.DmMG[T^=
G9GHBwT
/** ;C=V- r
* @author Joa 0AF,} &$
* D,|TQQ
*/ N eP
publicclass PageUtil { atw*t1)g
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privatestaticfinal Log logger = LogFactory.getLog >AY9F|:
2|]
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(PageUtil.class); f9
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/** 2oOos%0
* Use the origin page to create a new page og~a*my3
* @param page D:?"Rf{)
* @param totalRecords _MuzD&^qE
* @return b\zq,0%
*/ qR_Np5nHF
publicstatic Page createPage(Page page, int cIa`pU,6A
TTbJ9O<43
totalRecords){ {P\Ob0)q
return createPage(page.getEveryPage(), -AU'1iRcK7
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page.getCurrentPage(), totalRecords); "%S-(ue:
} 5w{U/v$Z
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/** J><hrZ
* the basic page utils not including exception >Z<ZT
qm'@o -[
handler %e)vl[:}
* @param everyPage ,\#j6R,{I
* @param currentPage "Mv^S'?>
* @param totalRecords w5rtYTI
* @return page l-!"
*/ m=v.<+>
publicstatic Page createPage(int everyPage, int Z#[%JUYp'
$}5M`p\&C
currentPage, int totalRecords){ $: 1/`m19
everyPage = getEveryPage(everyPage); ;=E}PbZt2
currentPage = getCurrentPage(currentPage); H 8 66,]
int beginIndex = getBeginIndex(everyPage, X56q,jCJ{
TiZ
MY:^
currentPage); Dq9f Fe
int totalPage = getTotalPage(everyPage, sSD&'K=lq
(2"4PU8
totalRecords); mo=@Zt
boolean hasNextPage = hasNextPage(currentPage, ~k?t
z|Xt'?9&n
totalPage);
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boolean hasPrePage = hasPrePage(currentPage); 3[l\l5'm8
-em3 #V
returnnew Page(hasPrePage, hasNextPage, e8egxm
everyPage, totalPage, d{(Rs.GuP
currentPage, R$MR|
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beginIndex); f`\J%9U _O
} K@!hrye
aO9\8\^
privatestaticint getEveryPage(int everyPage){ b}u#MU
return everyPage == 0 ? 10 : everyPage; XRyeEwA;pp
} }v?l0Gk(
:J )^gc
privatestaticint getCurrentPage(int currentPage){ XuZgyt"=r
return currentPage == 0 ? 1 : currentPage; Y2N$&]O{
} 1hV&/Qr
36.mf_AM
privatestaticint getBeginIndex(int everyPage, int 8
?:W{GAo
@wP.Rd
currentPage){ YxA nh
return(currentPage - 1) * everyPage; /8hjs{(;
} ?9 `T_,
`$3P@SO"
privatestaticint getTotalPage(int everyPage, int 9{A*[.XK]
cRf;7G
totalRecords){ 40-/t*2Ly
int totalPage = 0; _nw\ac#*
`<Hc,D; p
if(totalRecords % everyPage == 0) "[Tr"nI
totalPage = totalRecords / everyPage; lb"T'}q
else (ueH@A"9;
totalPage = totalRecords / everyPage + 1 ; 3z8zZ1uzU
k<"N^+GSz
return totalPage; Ag1nxV1M$
} ?:zMrlX
y92<(ziaX)
privatestaticboolean hasPrePage(int currentPage){ *S Z]xrs
return currentPage == 1 ? false : true; [~Z#yEiW^
} j{zVVT
sn@)L ~$V
privatestaticboolean hasNextPage(int currentPage, -**fT?n
T(~^X-k
int totalPage){ O9p^P%U "
return currentPage == totalPage || totalPage == ab 6D &
i l%9j
0 ? false : true; v\kd78,
} q#Ik3 5
2Ju,P_<dt
`R$bx 64
} 8}^ym^H|j
"M]`>eixL
N=:xyv
bW'Y8ok[v
WS$~o*Z8
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 uQW d1>
%,) Xi
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 P~"""3de4
]6HnK%
做法如下: ra\|c>[%
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ?Ye%k
lHPhZ(Z
的信息,和一个结果集List: @(rLn
java代码: sZU
Ao&
u\UI6/
5d82M s
/*Created on 2005-6-13*/ :#W>lq@H
package com.adt.bo; 8L(KdDY
);x[1*e
import java.util.List; !E\J`K0_e
TC'^O0aZ_
import org.flyware.util.page.Page; TUVqQ\oF:
dtq]_HvTJ
/** K+c>Cj}H
* @author Joa h$fC/Juit
*/ O<w7PS
publicclass Result { rYr.mX
(fWQ?6[
private Page page; I~Zm**L
'
9
private List content; cV)~%e/
&,`P%a&k
/** j-etEWOTr
* The default constructor Tk4"qGC.
*/ BLhuYuON
public Result(){ Cqk6I gw
super(); FKB)o7
} zL3'',Ha
5=Y\d,SS"
/** \7,'o] >M-
* The constructor using fields uw@|Y{(K r
* *,DBRJ_*7
* @param page .{W)E
* @param content \(bML#I
*/ 'H,l\i@"
public Result(Page page, List content){ 2]*2b{gF,
this.page = page; %@FTg$
this.content = content; BK]q^.7+:
} ?5 d3k%
Y,@{1X`0@3
/** +<H)DPG<
* @return Returns the content. Ie?C<(8Ul
*/ 4m6E~_:F
publicList getContent(){ ;=6~,k)
return content; &6L{1
} A3N<;OOk
bmO[9
)G
/** p`JD8c
* @return Returns the page. wy$9QN
*/ f z8eL:i:
public Page getPage(){ 8+1tys
return page; OPwj*b:-m
} xGeRoW(X
Ij }RlYQz
/** u#Qd`@p
* @param content mPxph>o
* The content to set. jC<!Ny-$
*/ DO$jX
4
public void setContent(List content){ X&6p_Lo
this.content = content; \qqt/
} MI@id
DxT8;`I%
/** ,P<n\(DQ
* @param page snV,rZ
* The page to set. Q': }'CI
*/ =x~HcsJ8!R
publicvoid setPage(Page page){ W9T,1h5x
this.page = page; R;f!s/^)
} w7]@QTC
} ".eD&oX{
W@1Nit-R
%uyRpG3,
hof:+aW
[dL4u^]{
2. 编写业务逻辑接口,并实现它(UserManager, }}v;V*_V
|b52JF
",
UserManagerImpl) qde.;Yv9
java代码: Mjrl KI}f/
9Bl_t}0
m#mM2Guxe
/*Created on 2005-7-15*/ eW]K~SPd7
package com.adt.service; SqTO~zGC
t7("geN]
import net.sf.hibernate.HibernateException; u~6`9'Ms
X 6/k `J
import org.flyware.util.page.Page; g6k@E,cI_
jAmAT/ 1
import com.adt.bo.Result; =usx' #rb
`(?E-~#'
/** 9Nglt3J[
* @author Joa cejSGsW6q
*/ Ft>Abj,6
publicinterface UserManager {
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! q!
=VC
public Result listUser(Page page)throws n3-u.Fb
0x'>}5`5
HibernateException; Nrva?W_i
K.n #;|
} !dYkvoQNn
Zg%U4m:
l)fF)\ |;=
Slcf=
$$2\qN -
java代码: <P7f\$o~
b40zYH`'{
d {a^
/*Created on 2005-7-15*/ MOY.$M,1
package com.adt.service.impl; 5zX;/n~
r}MXXn,f
import java.util.List; 9~bje^M
kehv85
import net.sf.hibernate.HibernateException; at${^,&
@dV'v{:,
import org.flyware.util.page.Page; +.whEw(i
import org.flyware.util.page.PageUtil; ~xpU<Pd*
ZFNM>C^
import com.adt.bo.Result; Ey=(B'A~
import com.adt.dao.UserDAO; Mb=vIk{Bf
import com.adt.exception.ObjectNotFoundException; Tk9u+;=6$
import com.adt.service.UserManager;
cHs@1R/-s
Q5b?-
P
/** ',?v7&
* @author Joa ?2_Oa%M
*/ \B8tGog
publicclass UserManagerImpl implements UserManager { %*lOzC
-bu.Ar-#;h
private UserDAO userDAO; -z./6dQ
-$J\BkI
/** }$s#H{T!
* @param userDAO The userDAO to set. oE[wOq+
*/ j1%o+#df
publicvoid setUserDAO(UserDAO userDAO){ u;p{&\(]
this.userDAO = userDAO; I4:4)V?
} M.))UKSF
(wU<Kpt?J
/* (non-Javadoc) Ikql
* @see com.adt.service.UserManager#listUser xQ9P'ru
,3&XV%1
(org.flyware.util.page.Page) 9{@[l!]W
*/ 2W:R{dHE
public Result listUser(Page page)throws R7}=k)U?d@
2jV.\C k
HibernateException, ObjectNotFoundException { @H2c77%
int totalRecords = userDAO.getUserCount(); O*xC}$OOn
if(totalRecords == 0) 5wYYYo=
throw new ObjectNotFoundException b<>GF-`w
A Vf'"~?
("userNotExist"); e\%+~GUTC=
page = PageUtil.createPage(page, totalRecords); Osncl5PD)
List users = userDAO.getUserByPage(page); ["Mq
returnnew Result(page, users); GTL gj'B
} 8}z]B^?Fy
nf=*KS\v
} `!WtKqr%B
/RU'~(
DKw%z8ft|
"}
=RPc%9
5Z"IM8?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 P"d7Af
4.il4Qqy}i
询,接下来编写UserDAO的代码: mOgsO
3. UserDAO 和 UserDAOImpl: jej|B#?`
java代码: +TzZ
-5;Kyio
W <.h@Rz+
/*Created on 2005-7-15*/ 0qP&hybL[(
package com.adt.dao; aDEz|>q
!_EL{ /ko
import java.util.List; b{Srd3
=P'33)
\ )
import org.flyware.util.page.Page; T,N"8N{K"
EC9D.afy&
import net.sf.hibernate.HibernateException; #m>Rt~(,S
Z{-x}${
/** Ip c2Qsa
* @author Joa CUJP"u>8M
*/ `"~s<+
publicinterface UserDAO extends BaseDAO { DXX(q k)6
F>N3GPRl
publicList getUserByName(String name)throws 55lL aus
C- 25\
HibernateException; MV8Lk/zd?A
K&1o!<|
publicint getUserCount()throws HibernateException; W5'07N^
lIR0jgP@z
publicList getUserByPage(Page page)throws p1}Y|m!
bOIVe
HibernateException; 38Rod]\E
DGfhS` X
} e<_yr>9g"
_PTo!aJL
Cjvgf.>$
kk`BwRh)d;
}qf9ra
java代码: {sn :Lj0
!sF! (u7
9`[#4'1Mik
/*Created on 2005-7-15*/ k:?+75?$
package com.adt.dao.impl; 2m`4B_g A
79.J`}#
import java.util.List; ]>utLi5dX
lHYu-}TNP
import org.flyware.util.page.Page; qF9rY)ifm
{d|R67~V
import net.sf.hibernate.HibernateException; P1PP#>E-2
import net.sf.hibernate.Query; *q5'~)W<
[V#"7O vl
import com.adt.dao.UserDAO; S 6sSdo'
o?G^=0T
/** E)(`Z0
* @author Joa Ru%:
z>Y
*/ `[+9n2j
public class UserDAOImpl extends BaseDAOHibernateImpl q.(p.uD
!g? ~<`
implements UserDAO { kndP?#>
p1
tVx.J'"Y
/* (non-Javadoc) &}Y_EHj}
* @see com.adt.dao.UserDAO#getUserByName o3H+.u$
qa ![oMKc
(java.lang.String) -`e=u<Y9@
*/ 5H6GZ:hp
publicList getUserByName(String name)throws ,5\:\e0H
,2>:h"^
HibernateException { m RCgKW<
String querySentence = "FROM user in class Q^Ln`zMe
>J=x";,D|~
com.adt.po.User WHERE user.name=:name"; {d$S~
Query query = getSession().createQuery K{VF_S:
!2x"'o
(querySentence); *8p\.za1
query.setParameter("name", name); ADX}
return query.list(); #e%.z+7I
} 'Rfvr7G/?
F~d
!Ub$>
/* (non-Javadoc) C!w@Naj
* @see com.adt.dao.UserDAO#getUserCount() [Hdk=p
*/ 4~a0
publicint getUserCount()throws HibernateException { w8%yX$<
int count = 0; :Puv8[1i
String querySentence = "SELECT count(*) FROM 6\86E$f=h
>ge-yK 1
user in class com.adt.po.User"; e:[Kp6J
Query query = getSession().createQuery ZNB*Azi
{CH\TmSz
(querySentence); 9[N'HpQ3
count = ((Integer)query.iterate().next gx[#@(
>1ZMQgCG
()).intValue(); [v-?MS
return count; `Uk,5F5
} hl~(&D1^
M
_U$I7
/* (non-Javadoc) +:&(Ag
* @see com.adt.dao.UserDAO#getUserByPage o\]e}+1[o
Lu:!vTRmw
(org.flyware.util.page.Page) b&~uK"O'7d
*/ B_cn[?M
publicList getUserByPage(Page page)throws B_5q}Bp<
D~f.)kkC4
HibernateException { `?JrC3
String querySentence = "FROM user in class 2L<TqC{,-
[9?=&O#*
com.adt.po.User"; M`?/QU~
Query query = getSession().createQuery ;8
McG83
=r0!-[XCa
(querySentence); [RpFC4W
query.setFirstResult(page.getBeginIndex()) UjKHGsDi4
.setMaxResults(page.getEveryPage()); Tao lX*$5
return query.list(); Kg](kP
} X_!mZ\H7
I:6xDDpZG`
} %oor7 -l
r LfS9H
j|aT`UH03
oub4/0tN,~
LnJ7i"Q
至此,一个完整的分页程序完成。前台的只需要调用 <K\F/`c
d'3'{C|kk
userManager.listUser(page)即可得到一个Page对象和结果集对象 5R ec}H
Ej34^*m9k
的综合体,而传入的参数page对象则可以由前台传入,如果用 !m(6/*PAl
;%k%AXw
webwork,甚至可以直接在配置文件中指定。 t3s}U@(C
9hguC yr@h
下面给出一个webwork调用示例: rLKDeB
java代码: g<lX Xj2
#ASu
SQ
8 Zj>|u
/*Created on 2005-6-17*/ PRah?|*0s
package com.adt.action.user; W@S9}+wl*
J2cNwhZ
import java.util.List; AMm O+E?
h`GV[Oo :
import org.apache.commons.logging.Log; Fh/C{cX9g
import org.apache.commons.logging.LogFactory; O~Fk0}-
import org.flyware.util.page.Page; L"-&B$B:
hWW<]qzA,
import com.adt.bo.Result; plIx""a^h
import com.adt.service.UserService; -'VT
import com.opensymphony.xwork.Action; ;yXnPAtJ
S8cFD):q
/** P4AdfHk
* @author Joa vVf!XZF
*/ R 1 b`(
publicclass ListUser implementsAction{ ropiyT9;
Oxvw`a#
privatestaticfinal Log logger = LogFactory.getLog Cwh;+3?C|
puyL(ohem
(ListUser.class); N} h%8\
f:0n-me
private UserService userService; UmuFzw^
)K6{_~Kc\
private Page page; 0cbF.Um8
sg2C_]i,H
privateList users; sP
|i'
U
Oo(7
/* |Wgab5D>V
* (non-Javadoc) 7L6M#B[)e5
* 0Q9OQqg
m
* @see com.opensymphony.xwork.Action#execute() ;CZcY] ol
*/ `!8Z"xD
publicString execute()throwsException{ 'W*F[U*&HP
Result result = userService.listUser(page); eH8.O
page = result.getPage(); ZIl<y{
users = result.getContent(); [ub\DLl
return SUCCESS; 4#9-Z6kOk
} F)w83[5_d
GZt] 38V)g
/** hdL2`5RFF
* @return Returns the page. *ZGN!0/
*/ 9R[','x
public Page getPage(){ nSiNSLv
return page; AlxS?f2w
} DeSTo9A}!
s`YuH <8
/** lg+g:o
* @return Returns the users. $ZO<8|bW
*/ !y?hn$w0
publicList getUsers(){ tV9C33
return users; Rp*t"HSaAW
} KOx#LGz
eb\`)MI/
/** ]:s|.C%q I
* @param page "r"An"
* The page to set. P0z{R[KBH
*/ :t^})%
publicvoid setPage(Page page){ 5I,X#}K[
this.page = page; }8:
-I Nj4
} 2v1&%x:y#
Qu _T&
/** #>B1$(@
* @param users vq7%SEkES
* The users to set. Zr;=p"cXr
*/ gDNW~?/
publicvoid setUsers(List users){ J9.p8A^^2
this.users = users; &X,)+b=
} m0\}Cc
D.R
/** 3yB6]U
* @param userService 6CRPdLTDf
* The userService to set. R7c)C8/~
*/ Aq'E:/
publicvoid setUserService(UserService userService){ )#~fS28j
this.userService = userService; [F[<2{FQF
} K0=E4>z,`q
} SfSEA^@|
'TsZuZW]
`Kw8rG\]:
< DZ76
TcmZ0L^O
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, XPo'iI-
U2lC !j%K
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 c.A/{a
C,vc
aC?
么只需要: @SG"t,5s
java代码: Pt0} 9Q
|Umfq:W`y_
g4SYG)'R+
<?xml version="1.0"?> DLVs>?Y
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork Mv`L F
U]EuDNkO{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- cYy@
LNxE-Dp
1.0.dtd"> '!h0![OH
`Mp7})
<xwork> vek:/'sj3p
[pFu
]^X
<package name="user" extends="webwork- #33RhJu5,
4yZ+,hqJ<9
interceptors"> [d~bZS|(T(
9.OwH(Ax7
<!-- The default interceptor stack name L0|hc
*[~o~e/YCb
--> )^>XZ*eK
<default-interceptor-ref +y4AUU:Q
S}Y|s]6
name="myDefaultWebStack"/> Sc$8tLDLj
{$1$]p~3o
<action name="listUser" 5~%,u2
5h=TV
class="com.adt.action.user.ListUser"> X8SRQO^
<param P:,
x?T?J^
i@R$g~~-D
name="page.everyPage">10</param> >"<k8wn
<result dJ%Rk#?;A
]\ 2RVDC
name="success">/user/user_list.jsp</result> u6Qf*_- K
</action> TFYT vUn
|~bR.IA
</package> t-7U1B}=<C
.F$|j1y
</xwork> =i^<a7M~
,WB_C\.#XN
7}cDGdr
H9san5{
@6
;oN
-?YT Q@ W
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 MYhx'[4[3
7.e7Fi{
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。 E R]sDV
Z2rzb{oS}
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 bH\C5zt6(
hP1
l v7P
QSF"8Uk
p>:ef<.i
_))I.c=v
我写的一个用于分页的类,用了泛型了,hoho ~3bZ+*H>
EY)Gi`lK
java代码: <wt$Gglk
)W1(tEq59
mGe|8In
package com.intokr.util; Z%+BWS3YqY
)XP#W|;
import java.util.List; }{5mH:
N~):c2Kp<9
/** $Eio$TI
* 用于分页的类<br> 3T|Y}
* 可以用于传递查询的结果也可以用于传送查询的参数<br> @GG(7r\/B
* =9pw uH
* @version 0.01 !.3R~0b
* @author cheng o#xgrMB
*/ U~*c#U"bh
public class Paginator<E> { -!J2x8Ri
privateint count = 0; // 总记录数 I( ]BMMj
privateint p = 1; // 页编号 y !<'rg
privateint num = 20; // 每页的记录数 aXdf>2c{JD
privateList<E> results = null; // 结果 I#U>5"%\a
iW|s|1mh3
/** kDzj%sm!
* 结果总数 M%$DT
*/ ~{kM5:-iw
publicint getCount(){ \Z)#lF|^
return count; xfq]9<
} .Gizz</P~
JbE?a[Eg?
publicvoid setCount(int count){ %won=TG8
this.count = count; O)`fvpVU
} #B @X
b'velj3A
/** Y4mC_4EU
* 本结果所在的页码,从1开始 n6b3E*
* T8n-u b<
* @return Returns the pageNo. FU%~9NKX
*/ rdO@X9z
publicint getP(){ 8q?;2w\l
return p; l8z%\p5cR
} <rNtY ,
x6LjcRS|
/** $v]T8|h
* if(p<=0) p=1 *^'wFbaBO
* `f@{Vcr%i
* @param p ><[|
G9
*/
Dk6?Nwy"
publicvoid setP(int p){ tNU-2r
if(p <= 0) U\Ct/U&A?
p = 1; Vo%Yf9C
this.p = p; 2s 7mI'
} Y2<dM/b/
Vu}806kB
/** n!a<:]b<
* 每页记录数量 $,TGP+vH
*/ qNpu}\L
publicint getNum(){ 'Q5&5UrBr
return num; *vYn_wE
} E#8_hT]5
K"L_`.&Q
/** 4IZlUJ?j+c
* if(num<1) num=1 )R~aA#<>
*/ q/$GE,"
publicvoid setNum(int num){ cf)J )
if(num < 1) \<ZLoy_
num = 1; !i^]UN
this.num = num; Ox^:)ii
} =`-|&
RX'-99M
/** QQFf5^
* 获得总页数 UFe(4]^
*/ tjj^O%SV<
publicint getPageNum(){ 9x?B5Ap[
return(count - 1) / num + 1; #zt*xS[{0
} [SkKz>rC
g` [` P@
/** 1* ^'\W.
* 获得本页的开始编号,为 (p-1)*num+1 dAL3. %
*/ 9${Xer'
publicint getStart(){ Hd%!Nt\u
return(p - 1) * num + 1; ^O)ve^P
} !,Nwts>m
_ij$f<
/** UQI
f}iR
* @return Returns the results. ;wR 'z$8
*/ ` H
XEZ|
publicList<E> getResults(){ *P!s{i
return results; ~zF2`.
} s]H^wrg&
\~#WY5
public void setResults(List<E> results){ _6MdF<Xb/
this.results = results; Gf0,RH+
} =X-Tcj?3g
g?G+dnl/8
public String toString(){ Cqxv"NN
StringBuilder buff = new StringBuilder ,O]l~)sr|
I%"'*7U
(); zN~6HZ_:^
buff.append("{"); 3A,rHYS
buff.append("count:").append(count); k1='c7s
buff.append(",p:").append(p); \.#p_U5In
buff.append(",nump:").append(num); k6(r !mc
buff.append(",results:").append y&oNv
xG-
bk<FL6z
z
(results); {G3i0r
buff.append("}"); 909md|9K3
return buff.toString(); o>?*X(+le
} W3rl^M=r
q; jiw#_
} ;%!B[+ut"
wX,F`e3"/
gSt`%