Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 LB? evewu
#PoUCRRC
detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .zlUN0oe
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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 h_?D%b~5
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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 9g"a`a?c
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分页支持类: Hh$D:ZO
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java代码: [@#P3g\:>W
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package com.javaeye.common.util; `"I^nD^t>Y
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import java.util.List; ~c! XQJ
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publicclass PaginationSupport { [>;U1Wt
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publicfinalstaticint PAGESIZE = 30; bY+Hf\A
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privateint pageSize = PAGESIZE; ED[PP2[/
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privateList items; s=~r. x
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privateint totalCount; s4;SA
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privateint[] indexes = newint[0]; l *yml
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privateint startIndex = 0; qW][Q%'lt
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public PaginationSupport(List items, int oVb6,Pn
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totalCount){ hn)mNb!
setPageSize(PAGESIZE); a5?Rj~h!<
setTotalCount(totalCount); Pf]6'?kQ
setItems(items); 3VB{Qj
setStartIndex(0); $eX ;
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} 0#G&8*FMN
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public PaginationSupport(List items, int wR@fB
+x-n,!(
totalCount, int startIndex){ 477jS6 ^e&
setPageSize(PAGESIZE); tE9%;8;H
setTotalCount(totalCount); wCkhE,#-_
setItems(items); JDD(e_dw
setStartIndex(startIndex); dW,$yH_
} j*q]-$ 2E
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public PaginationSupport(List items, int !R[o6V5T
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totalCount, int pageSize, int startIndex){ v#(wc+[
setPageSize(pageSize); jToA"udW/
setTotalCount(totalCount); (lwkg8WC
setItems(items); -1:yqF.x
setStartIndex(startIndex); $vTU|o>|
} Pd%o6~_*
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publicList getItems(){ D/9&pRsO
return items; %S]5wR6;_
} 8D;>] >
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publicvoid setItems(List items){ gUy >I(
this.items = items; @PU%BKe
} ,N<xyx.
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publicint getPageSize(){ )`,3/i9C$
return pageSize; X[(u]h`
} PE]jYyyHtU
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publicvoid setPageSize(int pageSize){ |TkMrj0
this.pageSize = pageSize; S)n~^q
} X@\rg}kP
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publicint getTotalCount(){ [wjA8d.
return totalCount; L@ql)Lc);
} H--(zxK
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publicvoid setTotalCount(int totalCount){ -SlLX\>p
if(totalCount > 0){ 0V}%'Ec<e
this.totalCount = totalCount; L/F!Y%=;[
int count = totalCount / m.&z:`x[
3EI$tP @4
pageSize; U9SByqa1
if(totalCount % pageSize > 0) b_|`jHes
count++; >(|T]u](q
indexes = newint[count]; W-<C%9O!
for(int i = 0; i < count; i++){ wZ0$ylEX
indexes = pageSize * 3*/y<Z'H
w=rh@S]
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} eXc`"T,C.
}else{ <omSK-
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this.totalCount = 0; qYl%v
} @tM1e<
} bvUjH5.7
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publicint[] getIndexes(){ v<ASkkh>
return indexes; h&{9 &D1t
} ,*+F*:o(m
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publicvoid setIndexes(int[] indexes){ Z7V1e<E
this.indexes = indexes; %S.
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} <2fZYt vt
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publicint getStartIndex(){
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return startIndex; w+fsw@dK&
} ,?3r-bM
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publicvoid setStartIndex(int startIndex){ mcP]k8?C
if(totalCount <= 0) -S"YEH9
this.startIndex = 0; 0/6f9A
elseif(startIndex >= totalCount) yrSmI)&%
this.startIndex = indexes Q=)$
ey _3ah3x
[indexes.length - 1]; ,ZHIXylZ
elseif(startIndex < 0) 7YV}F9h4
this.startIndex = 0; rUc2'Ct
else{ eBFsKOtu
this.startIndex = indexes %|*tL7
sy.FMy+
[startIndex / pageSize]; _rdEur C6
} FMc$?mm
} I%ivY
}u5/
publicint getNextIndex(){ hbl:~O&a/
int nextIndex = getStartIndex() + H{x'I@+
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pageSize; )>QpR8
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if(nextIndex >= totalCount) ^RAst1q7
return getStartIndex(); fZw/kjx@
else p9 <XaJ}
return nextIndex; 1Mn=m w
} zVKbM3(^
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publicint getPreviousIndex(){ h64<F3}
int previousIndex = getStartIndex() - !i,Eo-[Z
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pageSize; 93Kd7x-3
if(previousIndex < 0) mSm:>hBd
return0; A(V,qw8
else n`8BE9h^
return previousIndex; J$F
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} !nQ_<
1xP*
} ~2PD%+e7]
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抽象业务类 ^hr^f;N
java代码: XD%@Y~>+
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/** :[xFp}w{
* Created on 2005-7-12 uH="l.u
*/ F$.h+v
package com.javaeye.common.business; ?l/VCEZP
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import java.io.Serializable; O?L6Ues
import java.util.List; He vZ}.
a> qB
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import org.hibernate.Criteria; (yA`h@@WS
import org.hibernate.HibernateException; `yJ3"{uO
import org.hibernate.Session; h]T
import org.hibernate.criterion.DetachedCriteria; 0`UI^Y~Q
import org.hibernate.criterion.Projections; WVyk?SBw
import VUnO&zV{
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org.springframework.orm.hibernate3.HibernateCallback; pse$ S=
import 0Lb:N]5m8
opsjei@
org.springframework.orm.hibernate3.support.HibernateDaoS xl2;DFiYt
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upport; gr1NcHu
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import com.javaeye.common.util.PaginationSupport; +lC?Vpi^
!-rG1VI_S*
public abstract class AbstractManager extends mO<1&{qMZ
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HibernateDaoSupport { B0E`C
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privateboolean cacheQueries = false; X!,huB^i
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privateString queryCacheRegion; 3D 4-Wo4
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publicvoid setCacheQueries(boolean $ /`X7a{
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cacheQueries){ 4N6JKS
this.cacheQueries = cacheQueries; v}\4/u
} _4,/uG|a O
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publicvoid setQueryCacheRegion(String #mKF)W
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queryCacheRegion){ 59Lc-JJ
this.queryCacheRegion = p{|!LcSU$2
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queryCacheRegion; %9v l
} DwmK?5 p
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publicvoid save(finalObject entity){ hZ_@U?^
getHibernateTemplate().save(entity); :3b.`s(M
} boS=
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publicvoid persist(finalObject entity){ B@w/wH
getHibernateTemplate().save(entity); ?_ 476A
} ci
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publicvoid update(finalObject entity){ f8e :J#jbS
getHibernateTemplate().update(entity); sGFvSW
} %>'Zy6C<j
_=Z?5{7S>
publicvoid delete(finalObject entity){ `6y=ky.,
getHibernateTemplate().delete(entity); [[$dPa9
} eWWqK9B.-
] M`%@ps
publicObject load(finalClass entity, ylm #Xa
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finalSerializable id){ 36e
return getHibernateTemplate().load r[g
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(entity, id); @yM$Et5
} @U+#@6
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publicObject get(finalClass entity, p0rmcP1Ln
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finalSerializable id){ "7q!u,u
return getHibernateTemplate().get P{,A% t
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(entity, id); +pPfvE`
} ee/3=/H|;
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publicList findAll(finalClass entity){ Um^4[rl:#g
return getHibernateTemplate().find("from 9;7Gzr6A"
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" + entity.getName()); '8Cg2v5&w
} =kTHfdin&
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publicList findByNamedQuery(finalString j(A>M_f;
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namedQuery){ OUq%d8W
return getHibernateTemplate A(_HMqA]
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().findByNamedQuery(namedQuery); {p.^E5&
} &@K6;T
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publicList findByNamedQuery(finalString query, ayI<-s-
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finalObject parameter){ ZIN1y;dJ
return getHibernateTemplate ,eGguNA9
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().findByNamedQuery(query, parameter); <?nz>vz
} kXV;J$1
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publicList findByNamedQuery(finalString query, vHZq
z<
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finalObject[] parameters){ L{&>,ww
return getHibernateTemplate zLgc j(;
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().findByNamedQuery(query, parameters); Mw3$QRM
} E{0e5. {
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publicList find(finalString query){ + -uQ] ^n
return getHibernateTemplate().find <6Y|vEo!N
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(query); B(WmJ6e
} Wv|CJN;4
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publicList find(finalString query, finalObject r?itd)WC<X
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parameter){ ClY`2
return getHibernateTemplate().find Iprt
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(query, parameter); ic5af"/(\
} | }L=e.
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public PaginationSupport findPageByCriteria JH| D
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(final DetachedCriteria detachedCriteria){ i=L 86Ks
return findPageByCriteria x <a}*8"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Siq]Ii0F;>
} j,Mbl"P
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public PaginationSupport findPageByCriteria fF(AvMsO
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(final DetachedCriteria detachedCriteria, finalint ep~+]7\
ber&!9
startIndex){ @<3E`j'p
return findPageByCriteria DXG`% <ZMn
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(detachedCriteria, PaginationSupport.PAGESIZE, '<3h8\"
,ss"s3
startIndex); whYk"N
} wK0x\V6dJ
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public PaginationSupport findPageByCriteria BYu(a
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(final DetachedCriteria detachedCriteria, finalint W/\pqH
)H @<A93
pageSize, <jh7G
finalint startIndex){ -.r"|\1X
return(PaginationSupport) yUWc8]9\W
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getHibernateTemplate().execute(new HibernateCallback(){ ~r?tFE*+
publicObject doInHibernate KTt+}-vP^
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(Session session)throws HibernateException { i6P}MtC1
Criteria criteria = g4=C]\1
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detachedCriteria.getExecutableCriteria(session); e,{k!BXU#'
int totalCount = ysZ(*K
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((Integer) criteria.setProjection(Projections.rowCount [ )
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|||m5(`S
()).uniqueResult()).intValue(); i3mw.`7
criteria.setProjection _YG@P1
)Nqx=ms[(!
(null); %19~9Tw
List items = |$6Ten[B#
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criteria.setFirstResult(startIndex).setMaxResults ^SsdM#E
U#[T!E
(pageSize).list(); [<5/s$,i
PaginationSupport ps = yZ 7)|j
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new PaginationSupport(items, totalCount, pageSize, .rG~\Ws
w_o+;B|I
startIndex); bl&9O
return ps; YhNrg?nS
} 45n.%*,
}, true); )5n0P
Zi
} \9@}0}%`
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public List findAllByCriteria(final ?mM:oQH+>
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DetachedCriteria detachedCriteria){ R<gAxO%8
return(List) getHibernateTemplate sxA]o|
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().execute(new HibernateCallback(){ ;zze.kb&F
publicObject doInHibernate 2q]ZI
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(Session session)throws HibernateException { C$K?4$
Criteria criteria = J~xm[^0
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detachedCriteria.getExecutableCriteria(session); mi$C%~]5m
return criteria.list(); 4[#)p}V
} lAA-#YG
}, true);
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} b$0;fEvIJn
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public int getCountByCriteria(final ZbVn"he
)X," NJG
DetachedCriteria detachedCriteria){ y`8U0TE3R
Integer count = (Integer) Ym"^Ds}
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getHibernateTemplate().execute(new HibernateCallback(){ Du
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publicObject doInHibernate QHja4/
fd #QCs
(Session session)throws HibernateException { xjF>AAM_Px
Criteria criteria = ~:k
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detachedCriteria.getExecutableCriteria(session); TghT{h@
return <$hv{a
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criteria.setProjection(Projections.rowCount E+EcXf
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()).uniqueResult(); )MSCyPp5
} k&:q|[N
}, true); @aN~97
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return count.intValue(); k"%JyO8Y
} %).I&)i
} AX&Emz-
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用户在web层构造查询条件detachedCriteria,和可选的 \!jz1`]&{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Mv/ SU">F
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PaginationSupport的实例ps。 ?D7zty+}^
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ps.getItems()得到已分页好的结果集 x4>"m(&%
ps.getIndexes()得到分页索引的数组 -6WSYpHV
ps.getTotalCount()得到总结果数 AxH`4=3<
ps.getStartIndex()当前分页索引 BMQ4i&kF|
ps.getNextIndex()下一页索引 J=8Y D"1
ps.getPreviousIndex()上一页索引 z>0$SBQ-
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}@jJv||
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ^8bc<c:P
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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 Vv5T(~
<KtL,a=2+
一下代码重构了。 0FH.=
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我把原本我的做法也提供出来供大家讨论吧: k,'MmAz
0~_I9|FN
首先,为了实现分页查询,我封装了一个Page类: ollVg/z
java代码: !mWm@}Ujg
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/*Created on 2005-4-14*/ Gg
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package org.flyware.util.page; |7n%8JsY!"
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/** uVhzJu.
* @author Joa B 5qy4MFWs
* e2G;_:
*/ pRxVsOb
publicclass Page { ~*\ *8U@7
"Xwsu8~
/** imply if the page has previous page */ 7rbw_m`12-
privateboolean hasPrePage; 'byTM?Sp{
(RrC<5"
/** imply if the page has next page */ o(> #}[N}
privateboolean hasNextPage; Z
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1#;^Z3
/** the number of every page */ =_3rc\0
privateint everyPage; +\dKe[j{g
KRn[(yr`%
/** the total page number */ yKK9b
privateint totalPage; @].!}tz
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/** the number of current page */ bQ
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privateint currentPage; [e_csQ
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/** the begin index of the records by the current D%?9[Qb
~#VDJ[Z
query */ P*}aeu&lnD
privateint beginIndex; 7I]?:%8h
t5i58@{~
/B 3\e3
/** The default constructor */ l_9Z zN
public Page(){ &Qj1uf92.
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.
} 91yYR*
"|Y y"iB[
/** construct the page by everyPage sredL#]BA
* @param everyPage |/ 8!PKm
* */ MT)q?NcG
public Page(int everyPage){ ^r(]S%
this.everyPage = everyPage; 8KkN
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} (Rq6m`M2
|%#NA!e4wA
/** The whole constructor */ U7g,@/Qx
public Page(boolean hasPrePage, boolean hasNextPage, q(R|3l^6T
w@6y.v1I{
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int everyPage, int totalPage, i eWXr4@:
int currentPage, int beginIndex){ =oiz@Q @H
this.hasPrePage = hasPrePage; y0?HZ Xq
this.hasNextPage = hasNextPage; (|<+yQ,@>
this.everyPage = everyPage; 3 m-g-
this.totalPage = totalPage; {%P2.:
this.currentPage = currentPage; >o`+j$j
this.beginIndex = beginIndex; U H+#Nel+!
} qkp0' f*}
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/** o
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* @return =WZ9|e
* Returns the beginIndex. aMkuyqPf{
*/ ySDo(EI4
publicint getBeginIndex(){ N'l2$8
return beginIndex; (]&B'1b
} 9H:J&'Xi7
Zy?!;`c*{
/** HFFrS%
* @param beginIndex QuI!`/N)z
* The beginIndex to set. |f1^&97=+
*/ ZWjje6
publicvoid setBeginIndex(int beginIndex){ FjiIB1
T
this.beginIndex = beginIndex; s`[V{1m,
} dWi.V?K4z
L*4=b
(3
/** X_bB6A6
* @return g`.H)36
* Returns the currentPage. ~ oq.y n/1
*/ hBaG*J{
publicint getCurrentPage(){ {-]K!tWda
return currentPage; ;p<BiC$b
} Vj8-[ww!
(G$Q\>
/** =,qY\@fq
* @param currentPage iYw1{U
* The currentPage to set. O*]}0*CT
*/ 0(Z:QqpU$
publicvoid setCurrentPage(int currentPage){ 'gD./|Z0
this.currentPage = currentPage; QK #qW-49O
} I3sfOU
+u5xK
/** 4k<U5J
* @return #SI]^T|
* Returns the everyPage. E&Lml?@
*/ HB*BL+S06
publicint getEveryPage(){ 'Ce?!UO
return everyPage; #}~?8/h!
} 5
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z.2UZ%:
/** rxJl;!7G
* @param everyPage S+mBVk"-~S
* The everyPage to set. I1dOMu9
*/ Q[H4l({E
publicvoid setEveryPage(int everyPage){ g1 y@z8Z{
this.everyPage = everyPage; O ]-8 %
} K *1]P ar;
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/** --c)!Vxzx
* @return LL+_zBP.
* Returns the hasNextPage. J_|%8N{[x
*/ };Df ><
publicboolean getHasNextPage(){ 7`)RBhGB
return hasNextPage; gA1j'!\6l9
} \S?-[v*{
fT?m~W^
/** > hGB
o
* @param hasNextPage _Vt9ckaA
* The hasNextPage to set. + ~,q"6
*/ gOE?
publicvoid setHasNextPage(boolean hasNextPage){ i/!KUbt
this.hasNextPage = hasNextPage; WHLTJ]OB
} d#ab"&$bv
"Z&_*F.[O
/** P+_1*lOG
* @return "^
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* Returns the hasPrePage. ^ AZv4H*~
*/ P-yVc2YH
publicboolean getHasPrePage(){ C+t|fSJ
return hasPrePage; Z3u6m0!
} '%TD#!a
dPV<:uO
/** 5*90t{#
* @param hasPrePage mT|r:Yr:
* The hasPrePage to set. el<[Ng[
*/ [{vX*q
3B
publicvoid setHasPrePage(boolean hasPrePage){ =W"T=p*j
this.hasPrePage = hasPrePage; !kh: zTP
} <9$Pl%:
+I*a=qjq
/** u'T>Y1I
* @return Returns the totalPage. 8W7ET@`
* dg+"G|nr
*/ X%;4G^%ZI
publicint getTotalPage(){ dEX67rUj;
return totalPage; 5dX0C
} 8 QI+O`
dV*9bDkM/
/** ]a*26AbU+
* @param totalPage 20Jlf?
* The totalPage to set. L$, Kdpj
*/ cmd7-2
publicvoid setTotalPage(int totalPage){ "s`#`'
this.totalPage = totalPage; *kj+6`:CPs
} ox";%|PP1
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} LJ z6)kz
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rV-Xsf7Z
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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 6aWnj*dF
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个PageUtil,负责对Page对象进行构造: ,Vz-w;oDn
java代码: "N}MhcdS
DwTVoCC
4JH^R^O<n
/*Created on 2005-4-14*/ U:PtRSdn!b
package org.flyware.util.page; _tQM<~Y]u\
l Yj$3
import org.apache.commons.logging.Log; o nv0gb/J
import org.apache.commons.logging.LogFactory; V-63
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/** O[|X=ZwR:l
* @author Joa HA&hu/mw_
* s4=EyBI
*/ =#{q#COK$
publicclass PageUtil { :#N]s
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privatestaticfinal Log logger = LogFactory.getLog dn_l#$ U
q+?q[:nR-
(PageUtil.class); Y%zWaH
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/** }%y5<n*v\
* Use the origin page to create a new page ScT{Tb]9bt
* @param page @j(2tJ,w
* @param totalRecords 6"r _Y7%
* @return :/>Zky8,k
*/ {aU|BdATI
publicstatic Page createPage(Page page, int {817Svp@
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totalRecords){ :j32 :/u
return createPage(page.getEveryPage(), f]Rh<N$
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page.getCurrentPage(), totalRecords); 3A! |M5
} xxC2 h3
p@@*F+
/** \34:]NM
* the basic page utils not including exception YYe=E,q
-V'Y^Df
handler |#(y?! A^
* @param everyPage cCG!X%9
* @param currentPage
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* @param totalRecords 6_;n bqY&
* @return page [mG!-.ll
*/ 'PTQ
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publicstatic Page createPage(int everyPage, int 1V,DcolRY
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currentPage, int totalRecords){ b
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everyPage = getEveryPage(everyPage); rWN%j)#+
currentPage = getCurrentPage(currentPage); VwLo
int beginIndex = getBeginIndex(everyPage, )3 '8T>^<K
-O $!sFmY
currentPage); *3fhVl=8^*
int totalPage = getTotalPage(everyPage, CX]L'
gL7rX a j
totalRecords); 7oCY@>(f
boolean hasNextPage = hasNextPage(currentPage, z)u\(W*\iA
8rLhOA
totalPage); 6R#igLm
boolean hasPrePage = hasPrePage(currentPage); [z'jL'\4
rX?%{M,xFw
returnnew Page(hasPrePage, hasNextPage, 8/"C0I (G
everyPage, totalPage, qtz~Y~h|>
currentPage, q0nIJ(
UhU"[^YO
beginIndex); $OzVo&P;
} R)=){SI:1)
/:C<{m.[}
privatestaticint getEveryPage(int everyPage){ o"p['m*g
return everyPage == 0 ? 10 : everyPage; nIfp0U*
} Jpn= ^f[rm
8RcLs1n/
privatestaticint getCurrentPage(int currentPage){ L=I;0Ip9y
return currentPage == 0 ? 1 : currentPage; 2~yj
=D27Z
} P<LmCYm
CFu^i|7o
privatestaticint getBeginIndex(int everyPage, int $qR@;=
}>b@=5O
currentPage){ NE|Q0g
return(currentPage - 1) * everyPage; }V 4u`=
} 5>VX]nE3!
Z4sS;k]}
privatestaticint getTotalPage(int everyPage, int G#1W":|`
"EZpTy}Ee
totalRecords){ BxaGBK<k
int totalPage = 0; 4K|O?MUNS
\GZ|fmYn
if(totalRecords % everyPage == 0) \0FwxsL
totalPage = totalRecords / everyPage; tF.N
else >Udq{<]#r
totalPage = totalRecords / everyPage + 1 ; s#Xfu\CP
C;_0 0EQ=
return totalPage; UMK9[Iy$<M
} -U|Z9sia
nx%eq,Pq
privatestaticboolean hasPrePage(int currentPage){ Ou+b ce
return currentPage == 1 ? false : true; i*T
-9IP
} AN)r(86L
u>*qDr*d
privatestaticboolean hasNextPage(int currentPage, ^AoX|R[1%
eZ
7Atuv
int totalPage){ #9{2aRCJ
return currentPage == totalPage || totalPage == b&RsxW7
9!ARr@ ;
0 ? false : true; )&%Y{a#
} hd`jf97*
7/)0{B4U'
$h5QLN
} J.]`l\
%Nx,ZD@
7t/Y5Qf
h\+8eeIl
Y3SV6""y/
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 28 zZ3|Z3
#] ;ulDq
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Af}o/g
|<uBJ-5
做法如下: g@Rs.Zq
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7JBr{3;eS
v<mSd2B*
的信息,和一个结果集List: /L./-92NH4
java代码: #8y"1I=i&
wn\R|'Rdz
v4Kf{9q#
/*Created on 2005-6-13*/ ]2A2<Q_,
package com.adt.bo; ?6h~P:n.
n3$u9!|P
import java.util.List; 3#eAXIW[
3EE_"}H>
import org.flyware.util.page.Page; t[MM=6|Wb
imB/P M
/** alBnN<UM
* @author Joa 3 Zwhv+CP[
*/ Q% ^_<u
publicclass Result { Hoi~(Vc.
p$` ^A
private Page page; $9u:Ox
2
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private List content; J|VDZ# c7
Y' 5X4Ks|
/** >~tx8aI{
* The default constructor n'%cO]nSx
*/ dV-6 l6
public Result(){ T&}KUX~Q/
super(); b~(S;1NS'
} 5Fbb5`(
FtlJ3fB@
/** b;NV vc(
* The constructor using fields LLbI}:
* D}UgC\u
* @param page 1K'cT\aFm
* @param content "~Zdv}^xS
*/ md|I?vk
public Result(Page page, List content){ }vg|05L
this.page = page; uO1^nK
this.content = content; 7p>T6jK)
} r>.l^U9hJ
Qh*}v!3Jo
/**
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* @return Returns the content. Mky^X,r
*/ 5'%O]~
publicList getContent(){ J/PK#<
return content; Hr T@Df
} u`Kc\BSn
ft0tRv(s:
/** 12Fnv/[n'K
* @return Returns the page. I*/:rb
*/ !)05,6WQ
public Page getPage(){ C:f^&4
3
return page; q;_?e_
} 'Zqt~5=5
&v Q5+
/** 5glEV`.je
* @param content ch0cFF^]
* The content to set. `S4G+j>u6
*/ 3K/]{ dkD
public void setContent(List content){ vG=Pi'4XXo
this.content = content; =\\rk,F
} fgHsg@33N
Cv
p#=x0
/** #Yy5@A}`o
* @param page 3_T'0x\FP
* The page to set. u=E &jL5U
*/ Ec }9R3 m
publicvoid setPage(Page page){ qoW$Iw*q)B
this.page = page; A;f)`i0l,
} %CgmZTz~<
} p:ZQ*Ue
A5[kYD,_
Y^|15ek
Yk*_u}?#
V9%9nR!'
2. 编写业务逻辑接口,并实现它(UserManager, L:Faq1MG
P$3!4D[
UserManagerImpl) L3j
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java代码: 0
t/mLw&
!"aGo1$$
T8x /&g''
/*Created on 2005-7-15*/ @Y+kg
package com.adt.service; [FBc&HN
9_Z_5w;h
import net.sf.hibernate.HibernateException; #W8c)gkG9
%{me<\(
import org.flyware.util.page.Page; f/Z-dM\e
vq@"y%C4
import com.adt.bo.Result; "u{ymJ]t
;2^zkmDM
/** 0/cgOP!^
* @author Joa PE[5oH
*/ )ub!tm
publicinterface UserManager { mXsSOAD<
5bol)Z9BO
public Result listUser(Page page)throws YeB C6`7y
{yi!vw
HibernateException; #kJ8 qN
O.aAa5^uh
} '8I=Tn
7dlMDHp\Y
rERtOgi
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Qb;]4[3
java代码: |@?='E?h
kpk ^Uw%f
FtWO[*#
/*Created on 2005-7-15*/ `eGp.[ffT
package com.adt.service.impl; DnN+W
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import java.util.List; j}8^gz]
}Fu2%L>
import net.sf.hibernate.HibernateException; t=[/L]!
QEmktc1 7
import org.flyware.util.page.Page; E#kH>q@K`$
import org.flyware.util.page.PageUtil; 5F:\U
U)z1RHP|z
import com.adt.bo.Result; dO-Zj#%7z8
import com.adt.dao.UserDAO; dtXtZ!g2
import com.adt.exception.ObjectNotFoundException; s GrI%3[e"
import com.adt.service.UserManager; %H}M[_f
2 m72PU<.
/** dE(d'*+a
* @author Joa C ?\HB#41
*/ 9g$fFO
publicclass UserManagerImpl implements UserManager { g](&H$g
Af^9WJ
private UserDAO userDAO; >q&e.-qL
h@s i)5"
/** J,=^'K(
* @param userDAO The userDAO to set. +ERuZc$3,
*/ paxZlA
o
publicvoid setUserDAO(UserDAO userDAO){ 'qeUI}[
this.userDAO = userDAO; Y2+YmP*z`
} va.Ve# N
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/* (non-Javadoc) [c99m:*+
* @see com.adt.service.UserManager#listUser sr:hRQ27
\ow(4O#
(org.flyware.util.page.Page) q?f-h<yRQ
*/ -BsZw.
7P
public Result listUser(Page page)throws hiWs:Yq
ZjnWbnW
HibernateException, ObjectNotFoundException { Z,F1n/7
int totalRecords = userDAO.getUserCount(); r&XxF>
if(totalRecords == 0) :vC+}.{p
throw new ObjectNotFoundException MOIVt) ZY
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("userNotExist"); ;uuBX0B
page = PageUtil.createPage(page, totalRecords); \i)@"}
List users = userDAO.getUserByPage(page); <(us(zbk]
returnnew Result(page, users); \/r]Ra
} b_@bS<wsF}
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} t9_&n.z
C Y)[{r
EhN@;D+
L_IvR 4:j~
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 X`I=Z ysB
|@)jS.Bn
询,接下来编写UserDAO的代码: {_4zm&
3. UserDAO 和 UserDAOImpl:
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java代码: `1R[J4e
+ZRm1q
o:Tpd 0F
/*Created on 2005-7-15*/ _^^5
package com.adt.dao; /{Z<!7u;U
2{L[D9c/6
import java.util.List; QmsS,Zljo
jgw+c3^R_
import org.flyware.util.page.Page; k6_OP]
ITjg]taD
import net.sf.hibernate.HibernateException; "%=K_WJ?
4o@^._-R
/** yLt>OA<X
* @author Joa VO*fC
*/ ]Vf2Mn=]"
publicinterface UserDAO extends BaseDAO { AE%zqvp>
' PmBNT
publicList getUserByName(String name)throws ~hU^5R-%
'W[Nr
HibernateException; CWnRRZ}r
JZD&u6tB
publicint getUserCount()throws HibernateException; c$)!02
zM'2opiUY
publicList getUserByPage(Page page)throws gac/%_-HH7
'Ub\8<HfJU
HibernateException; E^m2:J]G
(DTkK5/%
} IPnx5#eB
Ly6) ,[q~
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0O?!fd n
iP?=5j=4
java代码: p2m`pT
Wt!NLlN8
E%)3{#.z
/*Created on 2005-7-15*/ vLM-v
package com.adt.dao.impl; diF2:80o
5%R$7>`Z
import java.util.List; *&W1|Qkg_
BctU`.
import org.flyware.util.page.Page; zMAlZ[DN
|JCn=v@
import net.sf.hibernate.HibernateException; P/dT;YhL
import net.sf.hibernate.Query; "J3n_3+
RSf*[2
import com.adt.dao.UserDAO; l' a<k"
~ponYc.Y
/** b_oUG_B3]
* @author Joa z)pp{
*/ rh(77x1|(G
public class UserDAOImpl extends BaseDAOHibernateImpl ZRoOdo94
M{U7yE6*j*
implements UserDAO { MY>o8A
u-~?ylh
/* (non-Javadoc) J<7nOB}OD
* @see com.adt.dao.UserDAO#getUserByName
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(java.lang.String) B_|jDH#RyJ
*/ x^6sjfAW
publicList getUserByName(String name)throws \jByJCN
dn=g!=
HibernateException { QgW4jIbx
String querySentence = "FROM user in class iYzm<3n?
^2!l/(?
com.adt.po.User WHERE user.name=:name"; l":Z. J
Query query = getSession().createQuery ;S^7Q5-
pkEqd"G
(querySentence); &V7{J9
query.setParameter("name", name); / 9soUt
return query.list(); _cXLQ)-
} w]VdIS
z
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/* (non-Javadoc) ngQ]
* @see com.adt.dao.UserDAO#getUserCount() !4!Y~7sI"\
*/ \Y}nehxG@
publicint getUserCount()throws HibernateException { /g]m,Y{OI
int count = 0; o_ SR
String querySentence = "SELECT count(*) FROM npdpKd+*K"
{!7 ^w
user in class com.adt.po.User"; k/}E(_e
Query query = getSession().createQuery (8OaXif
-OV!56&
(querySentence); hKYA 5]
count = ((Integer)query.iterate().next JGKiVBN
IH0qx_;P&
()).intValue(); )]C7+{ImC
return count; I:%O`F
} >gTrui{,
mkOj&Q
/* (non-Javadoc) 9DP6g<>B
* @see com.adt.dao.UserDAO#getUserByPage ,Q8)r0 c
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(org.flyware.util.page.Page) m\xE8D(,
*/ <xQHb^:
publicList getUserByPage(Page page)throws fo30f=^Gi
`l8^n0-
HibernateException { Up kw.`D`
String querySentence = "FROM user in class jB!Q8#&Q
Z&R{jQ,
com.adt.po.User"; :3Hr:~
Query query = getSession().createQuery wWR9dsB.;
AT4G]pT
(querySentence); `FL!L59nz
query.setFirstResult(page.getBeginIndex()) RtVG6'Y
.setMaxResults(page.getEveryPage()); hZ@Wl6FG;
return query.list(); Fi^Q]9.@{
} 3mnq=.<(w
?1u2P$d
} ]MXeWS(
Z6I^HG{:
~&Gw[Nd1
ngoAFb
o {bwWk7v6
至此,一个完整的分页程序完成。前台的只需要调用 Q(Dp116
gLef6q{}
userManager.listUser(page)即可得到一个Page对象和结果集对象 { f@k2^
s'/ g:aJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 'rwnAr
sOBy)vq?\
webwork,甚至可以直接在配置文件中指定。 (PmaVwF
"e\:Cq>\
下面给出一个webwork调用示例: ,#PeK(
java代码: f._FwD
Z
^tF
} 1> i
/*Created on 2005-6-17*/ YI*Av+Z)
package com.adt.action.user; h)qapC5z,
sKT GZA
import java.util.List; g&30@D"
mw1|>*X&R
import org.apache.commons.logging.Log; kU5chltGF
import org.apache.commons.logging.LogFactory; <ZV !fn
import org.flyware.util.page.Page; si nnHQ
\)pT+QxZ
import com.adt.bo.Result; H1FSN6'
import com.adt.service.UserService; v<z%\`y
import com.opensymphony.xwork.Action; A9[ELD>p
W c"f
/** 'bpx
* @author Joa M#Vl{ b
*/ 9_mys}+
publicclass ListUser implementsAction{ QDg\GA8|
\y9( b
privatestaticfinal Log logger = LogFactory.getLog @,RrAL}|
?6gC;B
(ListUser.class); N!}r(Dd*
9?M><bBX
private UserService userService; \i-HECc"U
4epE!`z_&
private Page page; i(XcNnn6
*LbRLwt
privateList users; 5X5 &(S\
8uR4ZE*
/* `eat7O
* (non-Javadoc) Vb`m3
* }-:s9Lt
* @see com.opensymphony.xwork.Action#execute() OA??fb,b
*/ BiQ7r=Dd.
publicString execute()throwsException{ MXbt`]`_
Result result = userService.listUser(page);
9I:H=5c
page = result.getPage(); {U&*8Q(/
users = result.getContent(); ?th`5K30
return SUCCESS; c:Tw.WA
} FbVdqO
_-^Lr
/`G!
/** $~<);dYu0
* @return Returns the page. at@B>Rb
*/ 1YmB2h[Z
public Page getPage(){ 0^Vc,\P?
return page; %Bo/vB'
} 6^pddGIG
777N0,o(
/** =X?jId{
* @return Returns the users. s5X .(;+
*/ \7QAk4I~
publicList getUsers(){ R <+K&_
return users; ]:B|_|H
} jOppru5U
wD-(3ZVd4
/** aO9a G*9T
* @param page @3/.W +
* The page to set. 6@TGa%:G
*/ GVT+c@Gx
publicvoid setPage(Page page){ *%^Vq
this.page = page; iol.RszlZ|
} &y?L^Aq
;Zb+WGyj
/** D&f(h][hH?
* @param users )E<<