Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^/KfH&E
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 P!\hnm)%4
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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 UC9{m252
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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 p?myuNd[
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分页支持类: WEa>)@
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java代码: CV^0.
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package com.javaeye.common.util; cb+y9wA
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import java.util.List; eOrYa3hQ
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publicclass PaginationSupport { J~J@ ]5/
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publicfinalstaticint PAGESIZE = 30; ;/Q6i
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privateint pageSize = PAGESIZE; d7~j^v)=^
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privateList items; _om[VKJd
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privateint totalCount; D9^7m
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privateint[] indexes = newint[0]; LP>UU ,Z
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privateint startIndex = 0; e{t=>vry
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public PaginationSupport(List items, int rA#s
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totalCount){ IIP.yyh>
setPageSize(PAGESIZE); 2Guvze_bU
setTotalCount(totalCount); <|JU(B
setItems(items); uu3M{*}
setStartIndex(0); i`~~+6`J
} + zDc
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public PaginationSupport(List items, int 4g!7
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totalCount, int startIndex){ " dT>KQ
setPageSize(PAGESIZE); !Zj#.6c9
setTotalCount(totalCount); 5DSuUEvWcL
setItems(items); cj^bh
setStartIndex(startIndex); &|z|SY]DL
} _?Ckq
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public PaginationSupport(List items, int :)LC gIQo
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totalCount, int pageSize, int startIndex){ ;Id"n7W
setPageSize(pageSize); I7b i@t
setTotalCount(totalCount); 7sguGwg) _
setItems(items); N(7u],(Om
setStartIndex(startIndex); 8bbVbP
} `$Kes;[X
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publicList getItems(){ O9;dd
yx
return items; qvN"1=nJ
} ~y@& }
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publicvoid setItems(List items){ [)iN)$Mv
this.items = items; '8={ sMy
} LT&/0
7?"9J`*
publicint getPageSize(){ XC}1_VWs
return pageSize; e#m1X6$.e
} "MTq{f2?
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publicvoid setPageSize(int pageSize){ 43F^J%G
this.pageSize = pageSize; 6,zDBax
} =ty2_6&>
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publicint getTotalCount(){ y0y+%H-
return totalCount; b8e*Pv/
} v'$ykZ!Z
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publicvoid setTotalCount(int totalCount){ P8u"T!G
if(totalCount > 0){ T5V$wmB\W
this.totalCount = totalCount; b2W; |
int count = totalCount /
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%D. @L
pageSize; 8W{ g
if(totalCount % pageSize > 0) I>!|3ElT
count++; L% zuI& q
indexes = newint[count]; -/1d&
for(int i = 0; i < count; i++){ ELD
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indexes = pageSize * NrW [Q3E$
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i; )y5iH){!
} [!5l0{0
}else{ `dP? 2-Z
this.totalCount = 0; nWd:>Ur
} YqkA&qL]#;
} 9B&
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publicint[] getIndexes(){ YALyZ.d
return indexes; =:kiSrBS3t
} *-+C<2"
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publicvoid setIndexes(int[] indexes){ OrzM
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this.indexes = indexes; r';Hxa '
} I<IC-k"Y
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publicint getStartIndex(){ hLCsQYNDU
return startIndex; O#A8t<f|M
} $]xE$dzJ
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publicvoid setStartIndex(int startIndex){ rE9Ta8j6
if(totalCount <= 0) 3{I=.mUUm
this.startIndex = 0; wrhBH;3
elseif(startIndex >= totalCount) &`-_)~5]
this.startIndex = indexes e?|d9;BO
~>lOl/n 5
[indexes.length - 1]; &%@/Dwr
elseif(startIndex < 0) RT1{+:l
this.startIndex = 0; [9'|7fdU
else{ Fa6H(L3
this.startIndex = indexes j'#)~>b
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[startIndex / pageSize]; Xq[:GUnt
} xq8}6Q
} ,M| QN*
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publicint getNextIndex(){ B!$V\Gs
int nextIndex = getStartIndex() + cu)@P 0I
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pageSize; I3V{"Nx6
if(nextIndex >= totalCount) c8H9_6
return getStartIndex(); dw@TbJ
else [P (rY
return nextIndex; 9(i0"hS^
} oNh68ON:c
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - "6 uTo0
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pageSize; Cb4d|yiS8
if(previousIndex < 0) @'6S[zU
return0; ubiQ8Bx
else \HBVNBY
return previousIndex; 7O;BS}Lv=
} WV5r$
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} ,AGM?&A
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抽象业务类 \SoYx5lf
java代码: 5P5A,K
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/** r{;VTQ
* Created on 2005-7-12 v
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*/ pe`TH::p
package com.javaeye.common.business; %OezaNOtm
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import java.io.Serializable; ^+.+IcH
import java.util.List; YD0vfwh
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import org.hibernate.Criteria; MbT
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import org.hibernate.HibernateException; sK""
import org.hibernate.Session; tS_xa
import org.hibernate.criterion.DetachedCriteria; bn<I#ZH2
import org.hibernate.criterion.Projections; t
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import "G i+zkVm
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org.springframework.orm.hibernate3.HibernateCallback;
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import =Ov;'MC
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org.springframework.orm.hibernate3.support.HibernateDaoS
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S
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upport; 4X(1
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import com.javaeye.common.util.PaginationSupport; .5Z,SGBf
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public abstract class AbstractManager extends pDq^W@Rq
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HibernateDaoSupport { 8`rAE_n`%
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privateboolean cacheQueries = false; ^Xt]wl*]+
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privateString queryCacheRegion; P}.yEta
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publicvoid setCacheQueries(boolean Wj
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cacheQueries){ a-UD_|!
this.cacheQueries = cacheQueries; I2Or&
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} 7DHT)9lD/
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publicvoid setQueryCacheRegion(String }{w_>!ee
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queryCacheRegion){ JJbM)B@-
this.queryCacheRegion = Q%AS;(d
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queryCacheRegion; 9^C!,A{u4
} =`7)X\i@z
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publicvoid save(finalObject entity){ ;|2;kvf"w
getHibernateTemplate().save(entity); +gD)Yd
} u1pYlu9IW
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publicvoid persist(finalObject entity){ NZw[.s>n
getHibernateTemplate().save(entity); J~yd]L>
} *fuGVA
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publicvoid update(finalObject entity){ =%nqMV(y
getHibernateTemplate().update(entity); CB{k;H
} :'^dy%&UB
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publicvoid delete(finalObject entity){ rTH[?mkf4
getHibernateTemplate().delete(entity); ?XTg%U
} |]2eGrGj4
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publicObject load(finalClass entity, 2}xFv2X
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finalSerializable id){ )lngef
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return getHibernateTemplate().load 1+PNy d
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(entity, id); 'k(~XA}X:
} Q+%m+ /Zq
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publicObject get(finalClass entity, GO:1
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finalSerializable id){ ,[K)E
return getHibernateTemplate().get n9-q5X^e>
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(entity, id); o"+&^
} WY.\<$7
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publicList findAll(finalClass entity){ |2t7mat
return getHibernateTemplate().find("from nD?M;XN
$0`$)(Y
" + entity.getName()); X-2S*L'
} /xm} ?t0U
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publicList findByNamedQuery(finalString Wp9
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namedQuery){ 3vGaT4TDx
return getHibernateTemplate U*+!w@
.
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().findByNamedQuery(namedQuery); 5)zh@aJ@
} .]P;fCQmM
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publicList findByNamedQuery(finalString query, S
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finalObject parameter){ a518N*]j
return getHibernateTemplate o!_; H}pq
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().findByNamedQuery(query, parameter); (9[C0e S
} [{!j9E?(
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publicList findByNamedQuery(finalString query, -9<yB
/*p?UW<*4
finalObject[] parameters){ 6Bq2?;5
return getHibernateTemplate Qc
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().findByNamedQuery(query, parameters); A
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} @.]K6qC
",
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publicList find(finalString query){ sT"tS>
return getHibernateTemplate().find 0-MasI&b
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(query); G`JwAy r'
} IOES3
g#<?OFl
publicList find(finalString query, finalObject =
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parameter){ -0J<R;cVs
return getHibernateTemplate().find j]F3[gpc
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(query, parameter); Q_|S^hxQ
} uM!r|X)8
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public PaginationSupport findPageByCriteria <Phr`/
{^O/MMB\\%
(final DetachedCriteria detachedCriteria){ cM'[;u
return findPageByCriteria }PD(kk6fX
w0%ex#lkm
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]~x/8%e76
} :bF2b..XOu
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public PaginationSupport findPageByCriteria 7z0uj
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(final DetachedCriteria detachedCriteria, finalint g:6}zHK
)^2jsy
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startIndex){ g<0%-p
return findPageByCriteria LFM5W&?
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(detachedCriteria, PaginationSupport.PAGESIZE, cw-JGqLx
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startIndex); [&}<!:9'
} ;%.k}R%O@
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public PaginationSupport findPageByCriteria
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w
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(final DetachedCriteria detachedCriteria, finalint ,7nb;$]
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pageSize, 0J,d9a [1
finalint startIndex){ G/;aZ
return(PaginationSupport) Jt^JE{m9%
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getHibernateTemplate().execute(new HibernateCallback(){ hQLx"R$
publicObject doInHibernate E0%Y%PQ**{
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(Session session)throws HibernateException { ?BZ`mrH^
Criteria criteria = cx%9UK*c
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detachedCriteria.getExecutableCriteria(session); Q6<Uuiw
int totalCount = >l*9DaZ
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((Integer) criteria.setProjection(Projections.rowCount wbKBwI5w
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()).uniqueResult()).intValue(); Pb&+(j
criteria.setProjection Jy
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(null); '"p*FN
List items = | Dpfh
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criteria.setFirstResult(startIndex).setMaxResults 90k|u'ikOp
rSCX$ @@F
(pageSize).list(); nk.Eq[08
PaginationSupport ps = f3B8,>
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new PaginationSupport(items, totalCount, pageSize, ^u&Khc~
y
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startIndex); jmVy4* P_
return ps; \(t>(4s_~
} ;AA7wK 4
}, true); $d[:4h~
} nezbmpL4
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public List findAllByCriteria(final ITPpT
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DetachedCriteria detachedCriteria){ w:(7fu=
return(List) getHibernateTemplate -zkL)<7
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().execute(new HibernateCallback(){ vK~KeZ\,p=
publicObject doInHibernate OvG |=
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(Session session)throws HibernateException { Y\S^DJy
Criteria criteria = iFchD\E*o
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detachedCriteria.getExecutableCriteria(session); .[s82c]]6
return criteria.list(); hvZR4|k>
} CUcjJ|MZ
}, true); mQuaO#
I,
} @y&,e,3!
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public int getCountByCriteria(final xM,(|p(
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DetachedCriteria detachedCriteria){ 8Y'"=!3
Integer count = (Integer) cYS+XBz
k=
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getHibernateTemplate().execute(new HibernateCallback(){ Jtk(yp{Zz
publicObject doInHibernate H43D=N&
,6pH *b$
(Session session)throws HibernateException { Xh!Pg)|E
Criteria criteria = 'mR+W{r
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detachedCriteria.getExecutableCriteria(session); ?"u-@E[m
return Ux]@prA q
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criteria.setProjection(Projections.rowCount
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&$im^0`r_
()).uniqueResult(); Rj=Om
} DlO;EH
}, true); (LPD
return count.intValue(); S`.-D+.68
} 6[7k}9`alz
} IQv>{h}
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- mXr6R?
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用户在web层构造查询条件detachedCriteria,和可选的 M lwQ_5O
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 [GM<Wt0
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PaginationSupport的实例ps。 ywte\}
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ps.getItems()得到已分页好的结果集 v21?
ps.getIndexes()得到分页索引的数组 ~Wv?p4
ps.getTotalCount()得到总结果数 !~v>&bCG>9
ps.getStartIndex()当前分页索引 (P8oXb+%
ps.getNextIndex()下一页索引 &i RX-)^u
ps.getPreviousIndex()上一页索引 r U5'hK
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 LcF3P
4
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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 A4h/oMis
g.s oNqt=
一下代码重构了。 rg.if"o
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我把原本我的做法也提供出来供大家讨论吧: F{tSfKy2
L~~Yh{<
首先,为了实现分页查询,我封装了一个Page类: JK^;-&
java代码: Y1IlH8+0
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/*Created on 2005-4-14*/ U)8]pUI+/P
package org.flyware.util.page; O1,[7F.4g
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/** |e>-v
* @author Joa pM3BBF%
* 6Tnzg`0I
*/ ]9Hy
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publicclass Page { Ea?.HRxl
Ags`%(
/** imply if the page has previous page */ <&iBR
privateboolean hasPrePage; (z7#KJ1+Aw
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/** imply if the page has next page */ ibyA~YUN/
privateboolean hasNextPage; `m^OnH
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/** the number of every page */ g=Di2j{A
privateint everyPage; s=4.Ovd\
+&@0;zSga
/** the total page number */ UEUTu}4y
privateint totalPage; ig{5]wZ(
-s"lW 7N^
/** the number of current page */ iXFaQ
privateint currentPage; 9K!='u`
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/** the begin index of the records by the current
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query */ !=:c8V
privateint beginIndex;
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/** The default constructor */ "f_Z.6WMY
public Page(){ a2TC,
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} "T|\
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/** construct the page by everyPage Cx[4
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* @param everyPage iq$/6!t
* */ /eQn$ZRP,
public Page(int everyPage){ jxvVp*-=<j
this.everyPage = everyPage; 8*wI^*Q
} e+wd>iiB
tANG ]
/** The whole constructor */ /
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public Page(boolean hasPrePage, boolean hasNextPage, il~,y8WTU{
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/7^~*
int everyPage, int totalPage, H;2pk
int currentPage, int beginIndex){ (&(f`c@I
this.hasPrePage = hasPrePage; zlfm})+G
this.hasNextPage = hasNextPage; EeO{G*pq
this.everyPage = everyPage; W=!f
this.totalPage = totalPage; rAKdf??
this.currentPage = currentPage; N!AFsWV
this.beginIndex = beginIndex; ;Peyo1
} '&d4x c
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/** =>G A_
* @return |{
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* Returns the beginIndex. q`P:PRgM
*/ `f'P
publicint getBeginIndex(){ <mN3:G
return beginIndex; ,P}c92;
} L6m'u6:1{
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/** Fr~xN!
* @param beginIndex e\<I:7%Rg
* The beginIndex to set. Gsb]e
*/ {8' 5
publicvoid setBeginIndex(int beginIndex){ ' vwBG=9C
this.beginIndex = beginIndex; Dng^4VRd
} >qE$:V"_5
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/** U&6f}=vC
* @return :|a[6Uwl\V
* Returns the currentPage. ydt1ED0Q-
*/ )l=j,4nn
publicint getCurrentPage(){ -8IiQRS
return currentPage; v,jU9D\
} J?&9ofj&
r$KDNa$/a
/** xInWcQ
* @param currentPage Y3[@(
* The currentPage to set. + '`RJ,K+[
*/ 5GKz@as8
publicvoid setCurrentPage(int currentPage){ 9g7T~|P
this.currentPage = currentPage; %^S1 fUwT
} zSu2B6YU}
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/** sdb#K?l
* @return 7$ 'ja
* Returns the everyPage. /vu7;xVG
*/ _xJ&p$&
publicint getEveryPage(){ _/Hu'9432
return everyPage; -a3C3!!
} N$?q Aek
IoC,\$s,
/** [K5afnq`
* @param everyPage B-RaAiE@
* The everyPage to set. S7bSR?~L[
*/ R$q:Ct
publicvoid setEveryPage(int everyPage){ m*1=-"P
this.everyPage = everyPage; DD1S]m
} {0?76|
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/** !59q@Mya[
* @return ZR1EtvVG
* Returns the hasNextPage. ,-):&V:jF
*/ u URf
publicboolean getHasNextPage(){ Pu=YQ
#F'
return hasNextPage; J? C"be=
} K$4Ky&89
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/** [Mx+t3M
* @param hasNextPage ="V6z$N
* The hasNextPage to set. LVSJK.B
*/ mz47lv1?
publicvoid setHasNextPage(boolean hasNextPage){ HxjhP(
this.hasNextPage = hasNextPage; +U[A.^t
} `W5f'RU
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/** #(%6urd
* @return QgP
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* Returns the hasPrePage. ='(:fHhhX
*/ w0pH|$"/P
publicboolean getHasPrePage(){ B{44|aq1 |
return hasPrePage; 3o h(d.Z
} 1c]GS&(RP
8"+Kz
/** L!\I>a5C0G
* @param hasPrePage cG.4%Va@s_
* The hasPrePage to set. +BESO
*/ Lx.X#n.]T
publicvoid setHasPrePage(boolean hasPrePage){ ~MOIrF
this.hasPrePage = hasPrePage; 9BP-Iet
} O%OeYO69
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/** ./u3z|q1
* @return Returns the totalPage. 0y?bwxkc
* 9Z}-%Z[,)
*/ yovC~
publicint getTotalPage(){ 2TdcZ<k}J
return totalPage; cf96z|^C
} J=
T!
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/** $. Ih-
* @param totalPage eKt~pzXwm
* The totalPage to set. [5H#ay
*/ m}rUc29cS,
publicvoid setTotalPage(int totalPage){ XOU
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this.totalPage = totalPage; >mz<=n
} HZ/e^"cpM
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} uZCPxog
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5-*/wKjLz
Vf0m7BJc3
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 }5EvBEv-)
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个PageUtil,负责对Page对象进行构造: s_/CJ6s
java代码: rOX\rI%0+
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i!(u4wTFF
/*Created on 2005-4-14*/ Tv!zqx#E
package org.flyware.util.page; P9BShC5
RK< uAiU
import org.apache.commons.logging.Log; >HyZ~M
import org.apache.commons.logging.LogFactory; G@s
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/** W2'u]1bs
* @author Joa &=~Jw5WK
* f-^JI*hj
*/ _vm ~yKId
publicclass PageUtil { p[>!;qI
`@RTfBBg
privatestaticfinal Log logger = LogFactory.getLog _->d41
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(PageUtil.class); iU+O(vi
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/** !Wgi[VB
* Use the origin page to create a new page !ap}+_IA7^
* @param page Ejmpg_kux
* @param totalRecords ]De<'x}
* @return XkDIP4v%
*/ I|(r1.[K
publicstatic Page createPage(Page page, int "\3C)Nz?
UyENzK<%u
totalRecords){ s^#B*
return createPage(page.getEveryPage(), s+DOr$\
;?4EVZ#o
page.getCurrentPage(), totalRecords); %py3fzg
} T,r?% G{XE
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/** zc K`hS
* the basic page utils not including exception {u~JR(C:
]lqLC
handler 9(6f:D
* @param everyPage 3N257]
* @param currentPage VYbH:4K@%
* @param totalRecords ^,}1^?*
* @return page zcGmru|k
*/ TophV}@B`
publicstatic Page createPage(int everyPage, int >cJix
1
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currentPage, int totalRecords){ VkFMr8@|
everyPage = getEveryPage(everyPage); cDS\=Bf
currentPage = getCurrentPage(currentPage); 52ExRG S
int beginIndex = getBeginIndex(everyPage, 0Xb,ne
7
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currentPage); z.lIlp2:
int totalPage = getTotalPage(everyPage, "zj[v1K9-A
T[Lz4;TRk5
totalRecords); [n4nnmM
boolean hasNextPage = hasNextPage(currentPage, Wz%H?m:g#
galzk $D
totalPage); jI Entk
boolean hasPrePage = hasPrePage(currentPage); G>=Fdt7Oc
9A~w2z\G
returnnew Page(hasPrePage, hasNextPage, rtNYX=P
everyPage, totalPage, iYD5~pK8
currentPage, sKCYGt$
hi`[
beginIndex); 0 30LT$&!
} .+A)^A
_ _!LTpp
privatestaticint getEveryPage(int everyPage){ D6-R>"}
return everyPage == 0 ? 10 : everyPage; P?p]sLrP
} |M`'
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privatestaticint getCurrentPage(int currentPage){ #N"m[$;QR
return currentPage == 0 ? 1 : currentPage; E5!vw@,
} A3)"+`&PUl
zZ6m`]{B9?
privatestaticint getBeginIndex(int everyPage, int 4_kY^"*#"
}ZK%@b>
currentPage){ ,~ q:rh+
return(currentPage - 1) * everyPage; eR%\_;}7;
} Qk? WX
(`B
4C/G &w&
privatestaticint getTotalPage(int everyPage, int {0~\ T[qm
4sRM"w;
totalRecords){ fV@[S
int totalPage = 0; z%S$~^=b
zOd*>
if(totalRecords % everyPage == 0) w"5Eyz-eO
totalPage = totalRecords / everyPage; ~m_{&,CA.
else `;Ho<26
totalPage = totalRecords / everyPage + 1 ; "iTjiH)Q(
<8(=Lv`)q
return totalPage; 4GbfA
.u
}
Y?TS,
@Ddz|4 vEi
privatestaticboolean hasPrePage(int currentPage){ "4\k1H"_
return currentPage == 1 ? false : true; ^D<CoxG
} L&c
&
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:.4O
Hp1
privatestaticboolean hasNextPage(int currentPage, T%%
0W J
D(l,Z
int totalPage){ 6@TU9AZS`
return currentPage == totalPage || totalPage == A|GtF3:G
]!ox2m_U
0 ? false : true; VwpC UW
} n&Ckfo_D
f`:GjA,J$
- w*fS,O
} U$mDAi$
hw,nA2w\
Vm|KL3}NRv
G<M0KU(
hs[x\:})/
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。 -nXP<v=V
(P`=9+
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 :h5G|^
$m;`O_-T
做法如下: vof8bQ{&
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 23P&n(.
T:u>7?8o
的信息,和一个结果集List: dzEi^*
(8
java代码: K(i}?9WD
tPQ|znB|
r[4n2Mys
/*Created on 2005-6-13*/ ~4khIz
package com.adt.bo; kN.;;HFq#
g:z<CSIq/
import java.util.List; D#UuIZ
''YqxJ fb
import org.flyware.util.page.Page; I<O$);DV'
N]w_9p~=1
/** u
[._RA
* @author Joa &nP0T-T5y
*/ gE _+r
publicclass Result { Vx(*OQ
/1MmOB
private Page page; "aOs#4N
RqgN<&g?
private List content; U xBd14-R_
kzKej"a;
/** Ec!!9dgRQ
* The default constructor (oi:lC@h*
*/ h{gFqkDoTI
public Result(){ \rFS^#
super(); Ww,\s5Uw
} }9+;-*m/
uR ?W|a
/** j@>D]j
* The constructor using fields Yy88 5
* Q]YB.n3
* @param page }:m/@LKB
* @param content ux<|8S
*/ o5bp~.m<
public Result(Page page, List content){ 1ZI1+TDH
this.page = page; M@R"-$Z
this.content = content; G9f6'5 O
} Ea&|kO|
A#.
%7S
/** xIGq+yd(
* @return Returns the content. >G:Q/3jh
*/ H].|K/-p
publicList getContent(){ 1Ng+mT
return content; >\d&LLAe
} oT-gZedW(
|Y>Jf~SN
/** WeM38&dWY
* @return Returns the page. kJJT`Ba&/
*/ au{)5W4~
public Page getPage(){ $Z:O&sD{
return page; 2)n`Bd
} o]4]fLQ
itg_+%^R
/** j(=w4Sd_W
* @param content 5tYo! f
* The content to set. (-gomn
*/ _#u\ar)
public void setContent(List content){ f' ?/P~[
this.content = content; Q#\Nhc
} n9'3~qVZ
t>[W]%op
/** riDb!oC
* @param page 17 Ugz?
* The page to set. 4rU/2}.q
*/ =]%JTGdp(
publicvoid setPage(Page page){ vN Bg&m
this.page = page; M]s\F(*ib
} C|V7ZL>W
} ;Z]Wj9iY
ij
?7MP
'XK 'T\m
g&s.
0+
PMfW;%I.
2. 编写业务逻辑接口,并实现它(UserManager, ,^:{!?v
n93q8U6m/U
UserManagerImpl) ?{ N,&d
java代码: IrMHAM5K
>Uw:cq
)0VL$A
/*Created on 2005-7-15*/ 'z ?Hv
package com.adt.service; AS7L
Az&>.*
import net.sf.hibernate.HibernateException; \N9=13W<lK
P_(8+)ud-
import org.flyware.util.page.Page; q&25,zWD
X'`n>1z
import com.adt.bo.Result; V|8'3=Z=
UxGu1a
/** qX,q*hr-
* @author Joa Lc{AB!Br
*/ w:5?ofC
publicinterface UserManager { aJ'Fn
32wtN8kx
public Result listUser(Page page)throws S(gr>eC5
cnu&!>8V
HibernateException; IL*B@E8
x3q^}sj%
} y
bhFDx
?2]fE[SqY
@7Ec(]yp
f/)Y {kS6
QP(0
java代码: y98FEG#S}
"wgPPop
M+ +Dk7B
/*Created on 2005-7-15*/ N3%#JdzZ$
package com.adt.service.impl; q3x"9i
`
\u,CixV=
import java.util.List; !D=!
8 0tA5AP
import net.sf.hibernate.HibernateException; 2FMmANH0ev
riIubX#
import org.flyware.util.page.Page; 0~U#DTx0
import org.flyware.util.page.PageUtil; Ui'v'
$
t]h_w7!U
import com.adt.bo.Result; #Zdh<.
import com.adt.dao.UserDAO; o%_-u
+
import com.adt.exception.ObjectNotFoundException; /HdXJL9B
import com.adt.service.UserManager; 1dN/H)]
r8EJ@pOF2w
/** @Tu`0=8
* @author Joa T8S&9BM7
*/ L1SX2F8
publicclass UserManagerImpl implements UserManager { ~O}r<PQ
D_l$"35?
private UserDAO userDAO; zDvV%+RW)
$MR1
*_\V
/** ctP+ECH
* @param userDAO The userDAO to set. n9Fq^^?
*/ evyjHc Cx
publicvoid setUserDAO(UserDAO userDAO){ f Fi=/}
this.userDAO = userDAO; Xh8U}w<k6
} ^T&{ORWz
WsHDIp
/* (non-Javadoc) fEBi'Ad
* @see com.adt.service.UserManager#listUser d]E=w6+;Q
.\oz
(org.flyware.util.page.Page) 5gf
~/Zr
*/ |Yl i~Qx
public Result listUser(Page page)throws HhynU/36
2 5~Z%_?
HibernateException, ObjectNotFoundException { QD-\'Bp/X
int totalRecords = userDAO.getUserCount(); Bl+\|[yd
if(totalRecords == 0) uuM1_nD[
throw new ObjectNotFoundException sVh)Ofn
QBa+xI_
J
("userNotExist"); *$9U/ d
page = PageUtil.createPage(page, totalRecords); WOO3z5 La
List users = userDAO.getUserByPage(page); 5Ew( 0K[
returnnew Result(page, users); 6 wN*d 5
} T6/P54S
n/v.U,f&l@
} cxR.:LD}
n.l#(`($4
#ft9ms#N
:q/s%`ob
o33t~@ RX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w[GEm,ZC
Zq4%O7%
询,接下来编写UserDAO的代码: AWcbbj6Nd
3. UserDAO 和 UserDAOImpl: #x.v)S
java代码: f/dJRcDl<
Tgpu 9V6
9wx]xg4l"
/*Created on 2005-7-15*/ AJ\gDjj<
package com.adt.dao; Y2VfJ}%Q
Tf#Op
v)
import java.util.List; ./I? |ih
u0W6u} 4;
import org.flyware.util.page.Page; #H6YI3
`G
)xVf3l
pQ
import net.sf.hibernate.HibernateException; lW"0fZ_x'E
~C{:G;Iy0
/** VP!4Nob
* @author Joa yV`Tw"p
*/ LGc8w>qE
publicinterface UserDAO extends BaseDAO { (&.T
*C55DO^w
publicList getUserByName(String name)throws mx)!] B"
%oqKpD+
HibernateException; Ko&4{}/
1V]ws}XW
publicint getUserCount()throws HibernateException; GG%;~4#2
azFJ-0n@"
publicList getUserByPage(Page page)throws Gd|kAC
g
f@`|2wG
HibernateException; /SJ><
N4x5!00
} 8pEA3py
`Hw][qy#
G+fo'ThG
r],%:imGr
F=Xb_Gd`
java代码: ^W sgAyCB
%KVmpWku
B.=n U
/*Created on 2005-7-15*/ Zb_A(mnzh
package com.adt.dao.impl; Z;N3mD+\ye
}bRn&)e
import java.util.List; K bQXH!J
xq.kH| bH
import org.flyware.util.page.Page; 5`3x(=b
r?u4[
Oe#
import net.sf.hibernate.HibernateException; }8AH/
import net.sf.hibernate.Query; kxJs4BY0
GH':Yk
import com.adt.dao.UserDAO; 5=*i!c
_m
<#8}![3Q
/** <}RD]Sc$1
* @author Joa HY_>sD
*/ CF3x\6.q}
public class UserDAOImpl extends BaseDAOHibernateImpl \A^8KVE!
(Zx--2lc
implements UserDAO { q~#>MB}".
_N:$|O#
/* (non-Javadoc) '+Jy//5?
* @see com.adt.dao.UserDAO#getUserByName e<uf)K=(C
Pm#/j;
(java.lang.String) )a0l:jEOc
*/ ;HAvor=?
publicList getUserByName(String name)throws Q\zaa9P
%7-(c
HibernateException { ;ZuHv {=
String querySentence = "FROM user in class xtCMK1#
x
E5A"sB
com.adt.po.User WHERE user.name=:name"; 3f$n8>mq
Query query = getSession().createQuery D5xQ
CH(Y.Kj-
(querySentence); M]X!D7
query.setParameter("name", name); _R|_1xa=
return query.list(); EKO'S+~
} :LB*l5\
~)#E?:h5
/* (non-Javadoc) &u^]YE{
* @see com.adt.dao.UserDAO#getUserCount() x~uDCbL
*/ 0'f\>4B
publicint getUserCount()throws HibernateException { OmkJP
int count = 0; +5I5
String querySentence = "SELECT count(*) FROM G11KAq(
a~@f,bw
user in class com.adt.po.User"; w:nH_x#C4
Query query = getSession().createQuery U]+I P;YS
Ohgu*5!o
(querySentence); oMemF3M
count = ((Integer)query.iterate().next UhDf6A`]
l?IeZisX
()).intValue(); 94O\M
RQ*
return count; ewT
K2
} OLt0Q.{
@f"[*7Q`/
/* (non-Javadoc) FO(QsR=\s
* @see com.adt.dao.UserDAO#getUserByPage %5+X
y|+5R5}K
(org.flyware.util.page.Page) &HLG<ISw
*/ _'Jjt9@S
publicList getUserByPage(Page page)throws L|<j/bP
b 1.S21
HibernateException { L_9uwua.B~
String querySentence = "FROM user in class FZ%h7Oe
7bbFUUUG"
com.adt.po.User"; OcWKK!A
Query query = getSession().createQuery \:s%;s51
\z6UWZ
(querySentence); d 4tL
query.setFirstResult(page.getBeginIndex()) huA?*fat
.setMaxResults(page.getEveryPage()); x6JV@wA&
return query.list(); 2gklGDJD
} ~9APc{"A
jP/Vqe%%8
} Gjq7@F'
_1Rw~}O
'_7rooU9
'Q=)-
8EkzSe
至此,一个完整的分页程序完成。前台的只需要调用 P@G U2[1
)TVd4s(e
userManager.listUser(page)即可得到一个Page对象和结果集对象 "y*3p0E
!oXFDC3k
的综合体,而传入的参数page对象则可以由前台传入,如果用 k4<28
Q|+ a
webwork,甚至可以直接在配置文件中指定。 >&e=0@?+G
Nz3+yxv1
下面给出一个webwork调用示例: [*It' J^
java代码: z.SKawm6T
*-fd$l.
a+J>
/*Created on 2005-6-17*/ 6Q>:vQ+E
package com.adt.action.user; oV['%Z'
Kyk{:UnI
import java.util.List; G"m0[|XH
3QZm
*.
/"
import org.apache.commons.logging.Log; bJ
6ivz
import org.apache.commons.logging.LogFactory; P-[})Z=
import org.flyware.util.page.Page; !pRu?5
U!Zj%H1XQ0
import com.adt.bo.Result; lr;ubBbT
import com.adt.service.UserService; iex%$> "
import com.opensymphony.xwork.Action; h*y+qk-!\g
$Yu'B_E6p
/** gloG_*W
* @author Joa [G|(E
*/ B%u[gNZ
publicclass ListUser implementsAction{ +J{ErsG?6P
1E||ft-1i*
privatestaticfinal Log logger = LogFactory.getLog XRkUv>Yk
q,#s m'S
(ListUser.class); IEm~^D#<=
(||qFu9a
private UserService userService; 'ParMT
8Uh|V&
private Page page; SD*q+Si,1U
PHT<]:"`<
privateList users; 'l!\2Wv2
l,Y5VGiH#
/* Oprfp^L
* (non-Javadoc) *szs"mQ/
* SX'NFdY
* @see com.opensymphony.xwork.Action#execute() h*JN0O<b
*/ W3Ee3
publicString execute()throwsException{ S9$,.aq
Result result = userService.listUser(page); 3)CIqN
page = result.getPage(); }&7kT7ogO
users = result.getContent(); vf>d{F^rv
return SUCCESS; Bi;a~qE
} }OnU32P
`_GCS,/t
/** 03|nP$g
* @return Returns the page. xjnAK!sD
*/ s}Go")p<:
public Page getPage(){ UMNNAX
return page; |Fze9kZO
} 3}phg
ns5Dydo{T
/** L.;x=w
* @return Returns the users. O^./)#!#
*/ )S4ga
publicList getUsers(){ OSUiS`k
return users; 8Vn
} 1V[ZklS
saZK+kD4I
/** &