Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 s.U p<Rw
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 *SZ<ori
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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 &2DW
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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 l`k3!EZDS
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分页支持类: h?b{{
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java代码: NZ#z{JI=+
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package com.javaeye.common.util; `^/Q"zH
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import java.util.List; #{(rOb6H)
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publicclass PaginationSupport { Ni`qU(I'|
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publicfinalstaticint PAGESIZE = 30; JQb]mU%?
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privateint pageSize = PAGESIZE; VC@o]t5
eP)RP6ON{
privateList items; *QLbrR
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privateint totalCount; Ugn"w E
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privateint[] indexes = newint[0]; {_Y\Y
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privateint startIndex = 0; GM5::M]fS
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public PaginationSupport(List items, int SFjN5u
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totalCount){ CAX U
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setPageSize(PAGESIZE); ("{'],>
setTotalCount(totalCount); *(rq AB0~
setItems(items); SF6n06UZu
setStartIndex(0); z)ydQw>
} ~HELMS~-
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public PaginationSupport(List items, int ~[C m#c
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totalCount, int startIndex){ .hvIq
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setPageSize(PAGESIZE); >7n(*M
setTotalCount(totalCount); vXc<#X9
setItems(items); N;htKcZ
setStartIndex(startIndex); i}!CY@sW
} )3 ;S;b
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public PaginationSupport(List items, int .e6 :/x~p*
O_E[FE:+
totalCount, int pageSize, int startIndex){ P6MT[
setPageSize(pageSize); *+b[v7
setTotalCount(totalCount); Zffzyh
setItems(items); yEH30zSt
setStartIndex(startIndex); @A:Xct
} P^
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publicList getItems(){ 3h4>edM
return items; 8NLk`/
} Eq|_>f@@8
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publicvoid setItems(List items){ {9z EnVfg
this.items = items; 4u<oe_n
} E]68IuP@'
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publicint getPageSize(){ \=.iM?T
return pageSize; "2 Kh2[K
} W<~(ieu:K~
km *$;Nli
publicvoid setPageSize(int pageSize){ $ED<:[3N
this.pageSize = pageSize; 5[0n'uH
} @6\8&(|
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publicint getTotalCount(){ ]g:VvTJ;?
return totalCount; -gzk,ymp
} mX
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publicvoid setTotalCount(int totalCount){ C,Ch6Ph
if(totalCount > 0){ _KKG^
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this.totalCount = totalCount; :}Z+K*%o-
int count = totalCount / =x=#Etj|
|S/nq_g]
pageSize; =l
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if(totalCount % pageSize > 0) 5{{u #W%=
count++; %KqXtc`O
indexes = newint[count]; `*WR[c
for(int i = 0; i < count; i++){ GR/
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indexes = pageSize * 90Q}9T\
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i; 7Ij'!@no
} pZXva9bE
}else{ qPWYY
this.totalCount = 0; #\fApRL
} iMF:~H-Yq#
} |Kb-oM&^#
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publicint[] getIndexes(){ HJwj,SL
return indexes; |ONkRxr@!
} hMdsR,Iq
OD{Rh(Id
publicvoid setIndexes(int[] indexes){ gVA$P
this.indexes = indexes; &Jq?tnNd
} L~~;i'J
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publicint getStartIndex(){ 8hdd1lVKO8
return startIndex; Wa
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} 9[/Gd{`XC
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publicvoid setStartIndex(int startIndex){ ZfS-W&6Z
if(totalCount <= 0) iGM-#{5
this.startIndex = 0; e:&5Cvx
elseif(startIndex >= totalCount) [@Y?'={qE
this.startIndex = indexes !RAyUfS
p.)G ],
[indexes.length - 1]; Jgb{Tl:r
elseif(startIndex < 0) '\P6NszY~
this.startIndex = 0; VDBP]LRF
else{ 8MV=?
this.startIndex = indexes iN<Tn8-YH6
a>6!?:Rj
[startIndex / pageSize]; *SLv$A
} 5s`NR<|2L
} m%ak ]rv([
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publicint getNextIndex(){ d-lC|5U%
int nextIndex = getStartIndex() + Za5*HCo
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pageSize; c)+IX;q-C
if(nextIndex >= totalCount) 0Kq\ oMn
return getStartIndex(); T-uI CMEf
else MYDAS-
return nextIndex; M{1't
} ]=7}Y%6
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publicint getPreviousIndex(){ aOETms w
int previousIndex = getStartIndex() - mKfT4t
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pageSize; a8Nl'
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if(previousIndex < 0) eE+zL~CE
return0; 4cl}ouG
else ZF>zzi+@
return previousIndex; b1R%JY7/S
} 6l<q
X*/jna"*
} 9H`Q
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抽象业务类 D`V03}\-
java代码: !D!Q]M5oU
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/** M1-n
* Created on 2005-7-12 Y7{IF X
*/ @/g%l1$`
package com.javaeye.common.business; aTxss:7]
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import java.io.Serializable; B~G?&"]
import java.util.List; nZ0-
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import org.hibernate.Criteria; )k&<D*5s
import org.hibernate.HibernateException; \GO^2&g(
import org.hibernate.Session; S=*rWh8)%<
import org.hibernate.criterion.DetachedCriteria; g:7S/L0]
import org.hibernate.criterion.Projections; <-D>^p9
import OTY9Q
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org.springframework.orm.hibernate3.HibernateCallback; xrs?"]M[
import :<r.n
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org.springframework.orm.hibernate3.support.HibernateDaoS +mIO*UQi
v[E*K@6f
upport; L'iENZI$
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import com.javaeye.common.util.PaginationSupport; j'R{llZW
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public abstract class AbstractManager extends J^m#984
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HibernateDaoSupport { e$u=>=jV]
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privateboolean cacheQueries = false; .B_LQ;0:
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privateString queryCacheRegion; 6vAq&Y{JB'
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publicvoid setCacheQueries(boolean hd^?mZ
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cacheQueries){ >x]b"@Hkw
this.cacheQueries = cacheQueries; CoO..
} ^cs:S-s
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publicvoid setQueryCacheRegion(String [#hpWNez(>
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queryCacheRegion){ @-qS[bV
this.queryCacheRegion = VRV*\*~$
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queryCacheRegion; R9@Dd
} E%8Op{zv_
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publicvoid save(finalObject entity){ $a.fQ<,\X
getHibernateTemplate().save(entity); k<(G)7'gm
} HI&N&a9C
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publicvoid persist(finalObject entity){ .$&mWytw=
getHibernateTemplate().save(entity); =;Ap+}
} s&&8~
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publicvoid update(finalObject entity){ v<CZ.-r\j
getHibernateTemplate().update(entity); &B?TX.
} 3>asl54
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publicvoid delete(finalObject entity){ {,xI|u2R
getHibernateTemplate().delete(entity); @D1}).
} pn"TFapJA
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publicObject load(finalClass entity, u-qwG/$E
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finalSerializable id){ $]LhE:!G
return getHibernateTemplate().load 11Sflj
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(entity, id); f4[fXP;A
} @N+ }cej
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publicObject get(finalClass entity, Ad7N'1O
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finalSerializable id){ VS`
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return getHibernateTemplate().get E&>3 {uZI
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(entity, id); 8.JFQ/)i
} ^V6cx2M
7 6 nrDE
publicList findAll(finalClass entity){ +\Uq=@
return getHibernateTemplate().find("from 4f~ c#0?
"-
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" + entity.getName()); WX~:Y,l+u
} b-!+Q)
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publicList findByNamedQuery(finalString x;N@_FZ7KY
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namedQuery){ }SD*@w
return getHibernateTemplate }Br=eaY
hSkI]%
().findByNamedQuery(namedQuery); lQ&"p+n
} G42J
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publicList findByNamedQuery(finalString query, 0nOkQVMk>
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finalObject parameter){ ;@ <E
return getHibernateTemplate &BOq%*+
Df hu
().findByNamedQuery(query, parameter); I'h|7y\
} Sjb[v
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publicList findByNamedQuery(finalString query, |NMf'$
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finalObject[] parameters){ b6(LoN.
return getHibernateTemplate Y9<N#h#
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().findByNamedQuery(query, parameters); [KcF0%a
} vD-m FC)
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publicList find(finalString query){ OKo)p`BX
return getHibernateTemplate().find QH>e_
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(query); *C~$<VYI
} 2.p?gRO
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publicList find(finalString query, finalObject _s{;9&qX]
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parameter){ e};\"^HH
return getHibernateTemplate().find 'v^Zterr
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(query, parameter); 2K:Rrn/cR
} 6[x6:{^J
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public PaginationSupport findPageByCriteria h/goV
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(final DetachedCriteria detachedCriteria){ 57|RE5]|!
return findPageByCriteria 9M12|X\]8
}+@GgipyO.
(detachedCriteria, PaginationSupport.PAGESIZE, 0); kO3N.t@n
} V|\dnVQ'-%
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public PaginationSupport findPageByCriteria C<B+! 16
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(final DetachedCriteria detachedCriteria, finalint 5jNDr`pnu
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startIndex){ %|izt/B
return findPageByCriteria [`n)2}
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(detachedCriteria, PaginationSupport.PAGESIZE, e)M)q!nG
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startIndex); >OxSrc@A
} q?##S'
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public PaginationSupport findPageByCriteria ^]zC~LfG
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(final DetachedCriteria detachedCriteria, finalint Cs2F/M'
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pageSize, CT0 ~
finalint startIndex){ a%YohfsY?U
return(PaginationSupport) lKSd]:3Xm
OD8{
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getHibernateTemplate().execute(new HibernateCallback(){ 1@Gmzh
publicObject doInHibernate o"gtWAGH
*Y]()#?Gr
(Session session)throws HibernateException { .,*68S0k7
Criteria criteria = <=Z`]8
Jfs_9g5
detachedCriteria.getExecutableCriteria(session); ,ZWaTp*D/
int totalCount = MszX9wl
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((Integer) criteria.setProjection(Projections.rowCount (#Ku`
$8{v_2C){
()).uniqueResult()).intValue(); ^q}cy1"j"
criteria.setProjection ;RzbPlkl
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(null); ;oM7H*WC
List items = MhL>6rn
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criteria.setFirstResult(startIndex).setMaxResults N<e72x
D.ERt)l>
(pageSize).list(); +:ih`q][b
PaginationSupport ps = 5fvY#6;
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new PaginationSupport(items, totalCount, pageSize, 0`Hr(J`F
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startIndex); M"\j7(
return ps; f=--$o0U~
} + t7n6
}, true); ?,z/+/:
} ad#4W0@S
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public List findAllByCriteria(final p*C| kE qk
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DetachedCriteria detachedCriteria){ [X^Oxs
return(List) getHibernateTemplate 5H79-QLd
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().execute(new HibernateCallback(){ 5Z_ 7Sc
publicObject doInHibernate ]
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(Session session)throws HibernateException { Q:^.Qs"IK
Criteria criteria = oD.[T)G?
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detachedCriteria.getExecutableCriteria(session); I6vy:5d
return criteria.list(); U'p-Ko#
} UAEu.AT
}, true);
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} U+ANSW/
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public int getCountByCriteria(final s9[547?`
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DetachedCriteria detachedCriteria){ ',bSJ4)Y
Integer count = (Integer) zPc kM)
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getHibernateTemplate().execute(new HibernateCallback(){ <HB@j}qi
publicObject doInHibernate k1E(SXcW9
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(Session session)throws HibernateException { nm#,oX2C
Criteria criteria = 60z8U#upM
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detachedCriteria.getExecutableCriteria(session); _ K Ix7
return RAU"
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criteria.setProjection(Projections.rowCount c-oIP~,
py }`thx
()).uniqueResult(); d}^G790
} AMre(lgh
}, true); L0X/
return count.intValue(); ?aWMU?S
} #p7K2
} >e"vPW*[
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用户在web层构造查询条件detachedCriteria,和可选的 TD-o-*mO
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 svvl`|n%
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PaginationSupport的实例ps。 i`^[_
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ps.getItems()得到已分页好的结果集 qV5lv-p
ps.getIndexes()得到分页索引的数组 hxZL/_n'
ps.getTotalCount()得到总结果数 0s!';g Q
ps.getStartIndex()当前分页索引 de_%#k1:L
ps.getNextIndex()下一页索引 O)$Pvll
ps.getPreviousIndex()上一页索引 tA8O(9OV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 7 g|EqJ7
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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 F1u2SltR
d1';d6.u\
一下代码重构了。 Tfp^h~&u
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我把原本我的做法也提供出来供大家讨论吧: 7S2"e[-x
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首先,为了实现分页查询,我封装了一个Page类: Z=dM7 Lj*
java代码: 'E"W;#%
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/*Created on 2005-4-14*/ 2EiE5@
package org.flyware.util.page; $X,dQ]M
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/** +~$pkxD"
* @author Joa G^Va$ike
* %JL P=(
*/ hsHbT^Qm
publicclass Page { 8Dkq+H93
,lcSJ^yr
/** imply if the page has previous page */ Y?ZzFd,i&
privateboolean hasPrePage; NXX/JJ+w
l5/gM[0_7
/** imply if the page has next page */ B \LmE+a>
privateboolean hasNextPage; SW}?y%~
`\$EPUM
/** the number of every page */ MdDL?ev
privateint everyPage; 5?q6g
oA?EJ ~%
/** the total page number */ #z+?t
privateint totalPage; {zalfw{+
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eh }t
/** the number of current page */ a"&cm'\lL
privateint currentPage; )4TP{tp
e2yCWolmTS
/** the begin index of the records by the current F:og :[
01~
nC@;
query */ SuXeUiK.[
privateint beginIndex; '+\t,>nRkl
x~Dj2F ]
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/** The default constructor */ IGOEqUw*
public Page(){ 82iFk`)T
sYbmL`{
} SBI*[
!Df>Q5~g
/** construct the page by everyPage .C` YO2,
* @param everyPage zpjE_|
* */ ]$=#:uf
public Page(int everyPage){ x4K A8
this.everyPage = everyPage; 6Ad C
} 1obajN
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/** The whole constructor */ cn Ohj
public Page(boolean hasPrePage, boolean hasNextPage, A*g-pJh
msY6zJc`
c:[ZknnCe
int everyPage, int totalPage, S_TD o
int currentPage, int beginIndex){ X'U~g$"(+
this.hasPrePage = hasPrePage; ]!j%Ad
this.hasNextPage = hasNextPage; ~1{ppc+
this.everyPage = everyPage; (vp#?-i
this.totalPage = totalPage; FGzKx9I9
this.currentPage = currentPage; 2;(+]Ad<
this.beginIndex = beginIndex; w+wtr[;wwL
} d<6m_!L
CXi[$nF3
/** bjo}95
* @return 9s1^hW2%Q
* Returns the beginIndex. 7Ie=(x8):
*/ LmytO$?2(
publicint getBeginIndex(){ fm L8n<1
return beginIndex; d8iq9AP\o
} 6bPl(.(3
S9{A}+"K
/** jtUqrJFlQ
* @param beginIndex &isKU8n
* The beginIndex to set. AvPPsN0
*/ F0~<p[9Nx
publicvoid setBeginIndex(int beginIndex){ CW2)1%1iz
this.beginIndex = beginIndex; =t`cHs29
} `ZbFky{
!*f$*,=^
/** [2Zl
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* @return C T\@>!'f
* Returns the currentPage. 7WwE] ^M
*/ b;%t*?t
publicint getCurrentPage(){ lh[?`+A
return currentPage; Z #T
} ,ga6
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/** 2WTOu x*
* @param currentPage s_a jA
* The currentPage to set. tt#dO@G#Fe
*/ 6oKdw|(Q#
publicvoid setCurrentPage(int currentPage){ VZq~ -$
this.currentPage = currentPage; S8Y\@C?5
} -i1 f
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J!2j]?D/e
/** h[&"KA
* @return `<7!Rh,tS^
* Returns the everyPage. Ij$C@hH
*/ T@Y, 7ccpd
publicint getEveryPage(){ yYaoA/0
return everyPage; ""Da2Md
} ;1s+1G}_z
#n}~u@,o_
/** 6i2%EC9
* @param everyPage L7d1)mV
* The everyPage to set. 7}g4ePYag
*/ |Fi5/$S.
publicvoid setEveryPage(int everyPage){ 1`YU9?
this.everyPage = everyPage; 5mC"8N1)
} DzQ
l#`G4Vf
/** #fYB4.i~
* @return tc<uS%XT4^
* Returns the hasNextPage. 6pSi-FH
*/ N0.|Mb"?t
publicboolean getHasNextPage(){ b>Y{,`E3
return hasNextPage; R(`:~@3\6
} TS#[[^!S
tq}45{FH3
/** jn:_2g[
* @param hasNextPage NC#F:M;b
* The hasNextPage to set. M
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*/ i'7+
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publicvoid setHasNextPage(boolean hasNextPage){ LP=j/qf|
this.hasNextPage = hasNextPage; d 8DU[p
} T*f/M
>WIc"y.
/** xbm%+
* @return G[A3H>
>
* Returns the hasPrePage. o87kF!x
*/ %VH, (}i
publicboolean getHasPrePage(){ nuXL{tg6
return hasPrePage; }:Gs ,
} sVK?sBs]
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/** IQRuqp KL
* @param hasPrePage v6s,lC5qR
* The hasPrePage to set. B*,)@h
*/ 0Gc@AG{
publicvoid setHasPrePage(boolean hasPrePage){ tqZ+2c<W3
this.hasPrePage = hasPrePage; EU %,tp
} !:^q_q4
%'yrIR
/** <;6{R#Tuh
* @return Returns the totalPage. {]< G=]'
* 8o$rF7.-
*/ eHuJFM
publicint getTotalPage(){ Bchv1KF
return totalPage; I I+y
} l6ym <V(1p
;^5k_\
/** yGdX>h
* @param totalPage Zgo~"G
* The totalPage to set. =FrB{Eu
*/ Gv_~@MN
publicvoid setTotalPage(int totalPage){ wQSye*ec
this.totalPage = totalPage; #GE]]7:Na
} Q$c6l[(g
)1uiY
f&k
} e@Lxduq
=~GP;=6
(Jk&U8y
n^Ca?|}
,
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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 nt#9j',6Rn
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个PageUtil,负责对Page对象进行构造: j#1G?MF
java代码: 9{*{Ba
P.'.KZJ:WD
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/*Created on 2005-4-14*/ %.Ma_4o
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package org.flyware.util.page; -B
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import org.apache.commons.logging.Log; >
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import org.apache.commons.logging.LogFactory; q 84*5-
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/** 5To@d|{
* @author Joa Y~WdN<g
* v Y0bK-
*/ ~5f&<,p!
publicclass PageUtil { *nCA6i
QB*,+u4
privatestaticfinal Log logger = LogFactory.getLog i6WH^IQ M
nm-
(PageUtil.class); j
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wq$$.
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/** tk&AZb,sP
* Use the origin page to create a new page \Ii{sn9
* @param page n#lbfN 4
* @param totalRecords 9D T<
* @return %MeAa?G-#
*/ Q":_\inF
publicstatic Page createPage(Page page, int m/KaWrw/)
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totalRecords){ )`DVPudiy
return createPage(page.getEveryPage(), HwUaaK
yQ$irS?
page.getCurrentPage(), totalRecords); ppyy0E^M
} ^M'(/O1
{821e&r
/** ] pn
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* the basic page utils not including exception |U%NPw5
'J,UKK\5
handler LwC?t3n
* @param everyPage r#sg5aS7O|
* @param currentPage ~#r>@C
* @param totalRecords qGk.7wf%
* @return page k=]e7~!
*/ 79T_9}M
publicstatic Page createPage(int everyPage, int Uwc%'=@
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currentPage, int totalRecords){ &C9IR,&
everyPage = getEveryPage(everyPage); EYT^*1,E*
currentPage = getCurrentPage(currentPage); ;6G]~}>o
int beginIndex = getBeginIndex(everyPage, A{+/$7vek
T}&A-V$
currentPage); ?Mjs [|
int totalPage = getTotalPage(everyPage, uY]';OtG
.g#}2:3
totalRecords); 4uXGpsL
boolean hasNextPage = hasNextPage(currentPage, K4Q{U@ZJ
>w3C
Ku<
totalPage); %xkuW]xk
boolean hasPrePage = hasPrePage(currentPage); C- YYG
!j6k]BgZ
returnnew Page(hasPrePage, hasNextPage, LT%~Cuf
everyPage, totalPage, MhMiSsZ
currentPage, o?baiOkH
7{#p'.nc5
beginIndex); b~gq8,Fatb
} ynsYU(
TGJz[Ny
privatestaticint getEveryPage(int everyPage){ ht-'O"d:
return everyPage == 0 ? 10 : everyPage; REh"/d
} 5U2%X
pO
Et 0gPX-
privatestaticint getCurrentPage(int currentPage){ '.v;/[0
return currentPage == 0 ? 1 : currentPage; -wn-PB@r
} +~5Lo'^
o?a2wY^_
privatestaticint getBeginIndex(int everyPage, int L4 po1
6tH}K
currentPage){ ~VsN\! G
return(currentPage - 1) * everyPage; w7MRuAJ4
} x1@,k=qrd
EXSH{P O+
privatestaticint getTotalPage(int everyPage, int Ku[q#_7
LphCx6f,X
totalRecords){ $<-a>~^Tp
int totalPage = 0; OLG)D#m(4/
rmjuNy=(
if(totalRecords % everyPage == 0) 1I2ndt
totalPage = totalRecords / everyPage; C6e5*S
else hC$e8t60
totalPage = totalRecords / everyPage + 1 ; Es[3Ppz
lMgguu~qg
return totalPage; CEj_{uf|
} !XTzsN
#VhdYDbW
privatestaticboolean hasPrePage(int currentPage){ y;az&T
return currentPage == 1 ? false : true; q,[;AHb
} }R*%q
l"J#Pvi
privatestaticboolean hasNextPage(int currentPage, o6u^hG6~'
Mc?_2<u-
int totalPage){ 3Dr\ O_`u
return currentPage == totalPage || totalPage == 3cJ'tRsp<
#?Ix6 {R
0 ? false : true; t ]BG)]
}
nS]e
ub?dfS9$_
KcT(/!
} -o/Vp>_UOE
LuRCkKJ
X!hzpg(`hR
=sWK;`
Ea4zC|;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ]+G
.S-a
1#Vd)vSP
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Yv1yRoDv
2z;nPup,
做法如下: rw)!>j+&A
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Eq_@xT0>
2 4od74\
的信息,和一个结果集List: Af\@J6viF7
java代码: "C}<umJ'
92j[b_P
(%6fZ
/*Created on 2005-6-13*/ O}C*weU
package com.adt.bo; 6EY\
5xc e1[
import java.util.List; whN<{AG
hrX/,D -c
import org.flyware.util.page.Page; j~bNH~3
`{ Ox=+]M
/** c{kpgN
* @author Joa LTf)`SN %'
*/ <mJ8~
publicclass Result { 0=+feB1T
]R~hzo
private Page page; {JdXn
gR/?MJ(v
private List content; 2 6}3
q"269W:
/** |zRrGQYm
* The default constructor BuvnY
*/ ~"*W;|)
public Result(){ ~APS_iG[
super(); ,OrrGwp&
} A#`$#CO
e6*,MnqBh
/** |Fx *,91
* The constructor using fields xm=Gt$>.o
* sw9ri}oc
* @param page 6lpJ+A57#
* @param content Ro{xprE1
*/ O\!'Ds+gX
public Result(Page page, List content){ |J@
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this.page = page; P\@kqf~pC
this.content = content; uNEl]Q]<e]
} IPTFx
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`#ff`j|a
/** jBEW("4R
* @return Returns the content. aQHR=.S]X
*/ ;eo}/-a_Xw
publicList getContent(){ ^$`mS&3/q
return content; ;[4=?GL*
} Fsl="RB7f
x;SY80D
/** ~p'|A}9[/
* @return Returns the page. #t2N=3dOj
*/ Z molL0y
public Page getPage(){ 97HI9R
return page; ;wJe%Nw?
} -~RGjx
R:l &2
/** \(`2 @
* @param content Y9-F\t=~
* The content to set. e1b?TF@lz
*/ Q e/XEW
public void setContent(List content){ +P9eE,WR
this.content = content; r(>812^\
} 8mOGEx
xVYa-I[Z
/** Z0M,YSn z
* @param page JPL`/WA0
* The page to set. 1.N2!:&G|
*/ +tt!xfy
publicvoid setPage(Page page){ : &nF>
this.page = page; 48S
NI
} yIr0D6L
} /]0SF_dZ
2&pE
}l} _'FmQ
TC2%n\GH*
b+gu<##
2. 编写业务逻辑接口,并实现它(UserManager, 2rC&
E 6MeM'sx
UserManagerImpl) J8@.qC'!
java代码: I5QtPqB>
sZ7,7E|_
XgXXBKf$
/*Created on 2005-7-15*/ Z0v?3v}9^
package com.adt.service; ]1zud
SXe1Q8;
import net.sf.hibernate.HibernateException; __+8wC
<_kA+&T
import org.flyware.util.page.Page; MSBrI3MqQ
mJ(ElDG
import com.adt.bo.Result; 7;Lv_Y"b
pUqNB_
/** g'w"U9tjO
* @author Joa "1XTgCu\
*/ )/[L)-~y~
publicinterface UserManager { XM"Qs.E
Yv)c\hm(7j
public Result listUser(Page page)throws m6^#pqSL
_OJfd
HibernateException; gm-9 oA
X
X!ldL|Ua%
} )}"`$6:k`
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fe
9
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KJS-{ed
gMZ+kP`
java代码: _NwHT`O[
br TP}A
#*w)rGkU2
/*Created on 2005-7-15*/ Ahbh,U
package com.adt.service.impl; {98e_z w
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import java.util.List; k'
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0s{7=Ef
import net.sf.hibernate.HibernateException; u>vvW|OB[
j+3rS
import org.flyware.util.page.Page; ?WqaT) l~
import org.flyware.util.page.PageUtil; :x5O1Zn/t
]9_}S
import com.adt.bo.Result; dHg[r|xC
import com.adt.dao.UserDAO; 5D<ZtsXE
import com.adt.exception.ObjectNotFoundException; [MKG5=kaE
import com.adt.service.UserManager; Qm*ZOz'i
?*
,
/** f9<"
* @author Joa \RPwSx
*/ 3OKs?i3A
publicclass UserManagerImpl implements UserManager { 1tI=Dwx
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private UserDAO userDAO; 7TI6EKr
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/** b$Dh|-8
* @param userDAO The userDAO to set. W#^.)V
*/ Wb cm1I)
publicvoid setUserDAO(UserDAO userDAO){ <Uj9~yVN]
this.userDAO = userDAO; X6(s][Wn
} \G)F*
9iM%kY#)W
/* (non-Javadoc) S3WUccv
* @see com.adt.service.UserManager#listUser 2P^qZDG 8I
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(org.flyware.util.page.Page) TXyiCS3
*/ Px*<-t|R-
public Result listUser(Page page)throws YHu]\'Ff
goF87^M
HibernateException, ObjectNotFoundException { [eOv fD
int totalRecords = userDAO.getUserCount(); v4'kV:;&
if(totalRecords == 0) dkDPze9l
throw new ObjectNotFoundException n|rKo<Y0
~LOE^6C+~o
("userNotExist"); IFS_DW
page = PageUtil.createPage(page, totalRecords); R?9x!@BV
List users = userDAO.getUserByPage(page); FINHO058^Y
returnnew Result(page, users); XpE847!soL
} Suo$wZ7J
}P{Wk7#Jq
} <Q- m &
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yf8kBT:&S
"8cI]~V
<;~u@^>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 rcMf1\
y@LiUe5
询,接下来编写UserDAO的代码: es x/{j;<u
3. UserDAO 和 UserDAOImpl: xh9$ZavB*
java代码: >zL5*:G
m_Q&zp["
_!,
J iOI
/*Created on 2005-7-15*/ q-_!&kDK"
package com.adt.dao; kmt1vV.9
bJD$!*r\%!
import java.util.List; ysp`(n=
ey4.Hj#T
import org.flyware.util.page.Page; NIbK3`1
w7Y@wa!
import net.sf.hibernate.HibernateException; 02*qf:kTnA
8=joVbs
/** udLI AV*
* @author Joa 6j6;lNUc
*/ fxr#T'i
publicinterface UserDAO extends BaseDAO { {N/%%O.b
\#B<'J9.`
publicList getUserByName(String name)throws iQ2j ejd3(
S
>CKm:7
HibernateException; %Pt){9b
9`Fw}yAt
publicint getUserCount()throws HibernateException; s<k2vbhI
vPz7*w
publicList getUserByPage(Page page)throws x(eX.>o\
^IIy>
HibernateException; v}V[sIs}
nM b@
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} l$EN7^%w
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dpNERc5
p@4GI[ 4
N8#j|yf
java代码: 51#OlvD
+)e|>
(?JdiY/
/*Created on 2005-7-15*/ bDtb6hL
package com.adt.dao.impl; 6b'.WB]-
>,]8iMh
import java.util.List; *tEqu%N1'
H;=Fq+
import org.flyware.util.page.Page; {A:uy
DR:$urU$
import net.sf.hibernate.HibernateException; |3@DCbT
import net.sf.hibernate.Query; 9_O4yTL
23>[-XZb[O
import com.adt.dao.UserDAO; lNa+NtQu
1nskf*Z
/** %>i:C-l8
* @author Joa Jut&J]{h
*/ u YT$$'S
public class UserDAOImpl extends BaseDAOHibernateImpl
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%KT}Map
implements UserDAO { e}d(.H%l0
uij^tN%
/* (non-Javadoc) RLnL9)`W
* @see com.adt.dao.UserDAO#getUserByName kv3Dn&<rJ
/+SLq`'u)
(java.lang.String) 9iZio3m
*/ B<m0YD?>~>
publicList getUserByName(String name)throws 0zq'Nf?#3
S\&3t}_
HibernateException { `;;l {8
String querySentence = "FROM user in class ty0P9.Q
;t\h"K<,|
com.adt.po.User WHERE user.name=:name"; }A24;'}
Query query = getSession().createQuery M]/aW
X4!7/&
(querySentence); Rxd4{L
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query.setParameter("name", name); )&7.E
return query.list(); ^Q$OzsEk
} #T^2=7 w
SXOAa<u5
/* (non-Javadoc) gaY&2
* @see com.adt.dao.UserDAO#getUserCount() x
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*/ }:Z A)
publicint getUserCount()throws HibernateException { 7D#y
int count = 0; iT4*~(p 3
String querySentence = "SELECT count(*) FROM bhpku=ov
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user in class com.adt.po.User"; )P:^A9&_n=
Query query = getSession().createQuery ?";SUku
,=m.WmXE
(querySentence); Jd>~gA}l
count = ((Integer)query.iterate().next s51$x M
J @"#
()).intValue(); +hmFFQQ}
return count; @9gZH_ur>E
} ^}d]O(
P6 OnE18n
/* (non-Javadoc) JF 4A
* @see com.adt.dao.UserDAO#getUserByPage -Qn7+?P
]19VEH
(org.flyware.util.page.Page) Vi8A4
*/ :/;/mHG]
publicList getUserByPage(Page page)throws EE!}$qOR
Ey46JO"
HibernateException { A =Wg0eYy\
String querySentence = "FROM user in class m~ tvuz I
#o.e
(C
com.adt.po.User"; >ZgzE
Query query = getSession().createQuery z$32rt8{`v
k_al*iM>H
(querySentence); >qjV{M
query.setFirstResult(page.getBeginIndex()) }]?Si6_ZZ
.setMaxResults(page.getEveryPage()); K}VCFV
return query.list(); j2Zp#E!
} $B+| &]a
*Z5^WHwg
} [VCC+_
tZrc4$D-
kNEEu!G
Lsmcj{1d
^PksXfk
至此,一个完整的分页程序完成。前台的只需要调用 J3K=z
c?p^!zG
userManager.listUser(page)即可得到一个Page对象和结果集对象 g,ZA\R~
yBIlwN`kB
的综合体,而传入的参数page对象则可以由前台传入,如果用 Y?T{>"_W
`BPTcL<W
webwork,甚至可以直接在配置文件中指定。 4`IM[DIG~
y7R#PkQ~
下面给出一个webwork调用示例: mo0\t#jA
java代码: o\AnM5
$`=p]
f-=\qSo
/*Created on 2005-6-17*/ :$ 5A3i
package com.adt.action.user; gg;r;3u
E h%61/
import java.util.List; pJpapA2l*6
jcH@*c=%e
import org.apache.commons.logging.Log; nR!e(
import org.apache.commons.logging.LogFactory; (
?V`|[+u
import org.flyware.util.page.Page; FqKJids-
;t`
?|
import com.adt.bo.Result; EP;/[O
import com.adt.service.UserService; !QUY (
import com.opensymphony.xwork.Action; P:qmg"i@3
!*IMWm>
/** ~}/Dl#9R!
* @author Joa l^B.iB
*/ E_HB[9
publicclass ListUser implementsAction{ Qy,^'fSN
B~Q-V&@o
privatestaticfinal Log logger = LogFactory.getLog f0Q6sV ZHa
dj|5'<l2
(ListUser.class); ]|;+2@kDR
(}"D x3K
private UserService userService; ,w
}Po
0P^h6Vat
private Page page; g(DD8;]w<
<_tmkLeZf
privateList users; +>w]T\[1~
]6&NIz`:,
/* \>L,X_DL
* (non-Javadoc) 5/48w-fnZ
* q>q:ZV
* @see com.opensymphony.xwork.Action#execute() 0bNvmZ$
*/ bm588UQ
publicString execute()throwsException{ yoi4w 7:
Result result = userService.listUser(page); LHAlXo;
page = result.getPage(); y!e]bvN
users = result.getContent(); s>rR\`
return SUCCESS; ejRK-!
} ajbe7#}
i jI/z5
/** k1 5vs
* @return Returns the page. gU9{~-9}
*/ X@nBj;
public Page getPage(){ mgxIxusR
return page; T?9D?u?]
} *P()&}JK
NOz3_k
/** NGra/s,9|
* @return Returns the users. A 'qe2]
*/ ^-;S&=
publicList getUsers(){ E(qYCafC
return users; iP/v"g"g
} U%{GLO
wI#8|,]"z
/** 7AG|'s['=
* @param page WlL(NrVA@@
* The page to set. l,wlxh$}(
*/ tz1@s nes
publicvoid setPage(Page page){ \lL[08G
this.page = page; !+xQ
} ?}||?2=P
Jx*cq;`Vee
/** J5@08bZm
* @param users pA7-B>Y
* The users to set. <Ij!x`MS+
*/ 5'lVh/
publicvoid setUsers(List users){ K/4@2vF
this.users = users; ^5 >e
} U}v`~'K
:I"CQ
C[Z
/** 2 a<\4w'
* @param userService 3WV(Ok
* The userService to set. ycGY5t@K@
*/ |9@,ri\'Rg
publicvoid setUserService(UserService userService){ 0SpB2>_
this.userService = userService; h!"2Ux3!x
} 8K8u|]i
} W?7l-k=S
G1:}{a5i_
EIi<g2pM(
%lKw+D
%zavSm"
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, S :HOlJze
:]"5UY?oF
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 OY*y<