Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9Pob|UA
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 H`6Jq?\
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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 WlQ&Yau
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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 GaK_9Eg-2
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。 }PIGj} F/
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分页支持类: +} ! F(c
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java代码: dT@SO
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package com.javaeye.common.util; /DG`Hg
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import java.util.List; |7Xpb
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publicclass PaginationSupport { !qGx(D{\
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publicfinalstaticint PAGESIZE = 30; =|5bhwU]
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privateint pageSize = PAGESIZE; %J (
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privateList items; q(PT'z
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privateint totalCount; i!}nGJGg
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privateint[] indexes = newint[0]; +i_f.Ipp
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privateint startIndex = 0; ,a_{ Y+
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public PaginationSupport(List items, int ^s2-jkK
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totalCount){ -"dy z(
setPageSize(PAGESIZE); k$x
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setTotalCount(totalCount); Rb}&c)4
setItems(items); rB&j"p}Q
setStartIndex(0); _DvPF~
} GxBPEIim
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public PaginationSupport(List items, int
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totalCount, int startIndex){ mF:s-+
setPageSize(PAGESIZE); 2l/5i]Tq
setTotalCount(totalCount); K2o0L5Lke
setItems(items); y~ 4nF
setStartIndex(startIndex); bOIM0<(h
} O+Lb***b"
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public PaginationSupport(List items, int B';>Hk
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totalCount, int pageSize, int startIndex){ a;owG/\p
setPageSize(pageSize); ="[](X^ l
setTotalCount(totalCount); |afK"N
setItems(items); L.%~?T[F
setStartIndex(startIndex); w|FVqX
} ;Owu:}
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publicList getItems(){ p6l@O3
return items; YM*6W?
} <RVtLTd/
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publicvoid setItems(List items){ 12'(MAP
this.items = items; /F}\V
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} 7^TXlWn^G
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publicint getPageSize(){ $yqq.#1
return pageSize; 8+cpNX
} HV7(6VSJ+
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publicvoid setPageSize(int pageSize){ W3/Stt$D
this.pageSize = pageSize; gWH9=%!
} r<N*N,~
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publicint getTotalCount(){ M`fXH 3D
return totalCount; YaT+BRh?
} &b")`p&K
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publicvoid setTotalCount(int totalCount){ ]hVXFHrR
if(totalCount > 0){ yBh"qnOT
this.totalCount = totalCount; .eXA.9|jm
int count = totalCount / 3C[4!>|
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pageSize; i*w-Q=
if(totalCount % pageSize > 0) &B0&183
count++; Y]Vc}-a(h
indexes = newint[count]; J15T!_AW<
for(int i = 0; i < count; i++){ >Io7h#[u
indexes = pageSize * at]Q4
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} `0sk2fn
}else{ 2]*~1d
this.totalCount = 0; lj*913aFh
} CHP6H}#|g
} arL&^]JnZ,
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publicint[] getIndexes(){ ^uElQI
return indexes; gc)3
} 6WcbJ_"mq
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publicvoid setIndexes(int[] indexes){ >F_Ne)}qTQ
this.indexes = indexes; !Qa7-
} |o)
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publicint getStartIndex(){ +%9Y7qol
return startIndex; %,D%Q~
} =:8=5tj
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publicvoid setStartIndex(int startIndex){ }0),b ?*e
if(totalCount <= 0) gdNp2b
this.startIndex = 0; LfM(DK
elseif(startIndex >= totalCount) ;#yz i2f
this.startIndex = indexes ^:ngHue8~
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[indexes.length - 1]; mLA$F4/K
elseif(startIndex < 0) O G}&%NgH
this.startIndex = 0; u Aa>6R
else{ --)[>6)I
this.startIndex = indexes UF&Wgj [
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[startIndex / pageSize]; FuBRb(I
} {z_pL^S'52
} Te#[+B?
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publicint getNextIndex(){ XX6)(
int nextIndex = getStartIndex() + Ve)
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pageSize; R~-q!nC
if(nextIndex >= totalCount) iO`f{?b
return getStartIndex(); CFxs`C^
else q)zvePO#
return nextIndex; n//a;m
} epm|pA*
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publicint getPreviousIndex(){ q[K)bg{HB
int previousIndex = getStartIndex() - Fj4:_(%nG
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pageSize; W#\4"'=I
if(previousIndex < 0) ]F!h~>
return0; ,fFJSY^
else $y}Tbm
return previousIndex; zv@o-R$l
} IYN`q'%|
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} kfV}w,
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抽象业务类 v<4zcMv
java代码: a3[aXe
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/** lom4z\6
* Created on 2005-7-12 YQJ_t@0C
*/ c\opPhJ!0
package com.javaeye.common.business; LBR_Q0EP
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import java.io.Serializable; 0)#I5tEre
import java.util.List; seim?LK
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; RIlPH~
import org.hibernate.Session; U*t`hn-xs
import org.hibernate.criterion.DetachedCriteria; GS@ wG
import org.hibernate.criterion.Projections; "]%
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import #'T@mA
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org.springframework.orm.hibernate3.HibernateCallback; p/:L;5F
import 5k @k
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org.springframework.orm.hibernate3.support.HibernateDaoS .KV?;{~q@
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upport; 4Q.70
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import com.javaeye.common.util.PaginationSupport; :iJ= 9
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public abstract class AbstractManager extends SVJ3!1B,
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HibernateDaoSupport { Sc(2c.HO*
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privateboolean cacheQueries = false; i^( 0,L
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privateString queryCacheRegion; h&XyMm9C
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publicvoid setCacheQueries(boolean "dt3peH
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cacheQueries){ ,}[,]-nVx
this.cacheQueries = cacheQueries; 0&Qn7L
} 6sntwT"?
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publicvoid setQueryCacheRegion(String b`IC)xN$
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queryCacheRegion){ * fx<>aK
this.queryCacheRegion = M@.1P<:h
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queryCacheRegion; mu(S9
} <I}k%q'
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publicvoid save(finalObject entity){ j1g^Q$B>m
getHibernateTemplate().save(entity); :f`1
} PR Y)hb;1
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publicvoid persist(finalObject entity){ sI`Lsd'V
getHibernateTemplate().save(entity); (FBKP#x)^
} Fw=-gb_.
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publicvoid update(finalObject entity){ 3ZC[H'|
getHibernateTemplate().update(entity); O,7P6
} 4Vt YR
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publicvoid delete(finalObject entity){ 0L|A
getHibernateTemplate().delete(entity); .
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} idV4hMF9
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publicObject load(finalClass entity, pbu 8Ib8z
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finalSerializable id){ ,]>Eg6B,u
return getHibernateTemplate().load =3sBWDB[
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(entity, id); ms<?BgCSz
} kz+P?mopm
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publicObject get(finalClass entity, ^oj)#(3C
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finalSerializable id){ `_<K#AG Ai
return getHibernateTemplate().get c8#A^q}
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(entity, id); ;A1pqHr
} D guAeK
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publicList findAll(finalClass entity){ ><dSwwu
return getHibernateTemplate().find("from Q4C28-#
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" + entity.getName()); [|e7oNT(Q
} F+|zCEc
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publicList findByNamedQuery(finalString Rm{S,
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namedQuery){ rm<(6zY
return getHibernateTemplate UuW"
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().findByNamedQuery(namedQuery); #"=_GA^.{
} ZEp UHdin
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publicList findByNamedQuery(finalString query, L+bU~N,+A
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finalObject parameter){ fHdPav f,S
return getHibernateTemplate ]HCu tq
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().findByNamedQuery(query, parameter); =EgiV<6vcH
} F`r=M%yh
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publicList findByNamedQuery(finalString query, ?dY}xE
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finalObject[] parameters){ e}D#vPaSY
return getHibernateTemplate vE^Hk!^
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().findByNamedQuery(query, parameters); ^W{+?q'
} x!"S`AM
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publicList find(finalString query){ 1$]4g/":o
return getHibernateTemplate().find q4C$-W%rj
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(query); !7]4sXL{
} WgF
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publicList find(finalString query, finalObject ^(r?k_i/
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parameter){ OB
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return getHibernateTemplate().find VQI
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(query, parameter); ov.7FZ+
} x >hnH{~w
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public PaginationSupport findPageByCriteria icLf;@
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(final DetachedCriteria detachedCriteria){ ),1MR=
return findPageByCriteria df; -E
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Y;JV9{j
} f^\qDvPur
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public PaginationSupport findPageByCriteria M[Lj N
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(final DetachedCriteria detachedCriteria, finalint H48`z'o
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startIndex){ Au(zvgP
return findPageByCriteria }c?/-ab>
*(5y;1KU
(detachedCriteria, PaginationSupport.PAGESIZE, {fW(e?8)
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startIndex); pVbgjJI
} s_xWvx8?4.
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public PaginationSupport findPageByCriteria ]Ng K(IU
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(final DetachedCriteria detachedCriteria, finalint qP@d)XRQ
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pageSize, 7.@$D;L9
finalint startIndex){ hqOy*!8'@
return(PaginationSupport) SUwSZ@l^|
$ J}d6%
getHibernateTemplate().execute(new HibernateCallback(){ BBnW0vAZ*
publicObject doInHibernate 4Rj;lAlwB
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(Session session)throws HibernateException { %6r MS}
Criteria criteria = F/GfEMSE
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detachedCriteria.getExecutableCriteria(session); X-,scm
int totalCount = `@?f@p$(B
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((Integer) criteria.setProjection(Projections.rowCount el
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()).uniqueResult()).intValue(); a![x^@nF
criteria.setProjection g%z'#E97
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(null); /Xa_Xg7
List items = Zqwxi1
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criteria.setFirstResult(startIndex).setMaxResults 4wfT8CL
=fk+"!-i%"
(pageSize).list(); : V16bRpjL
PaginationSupport ps = LS1r}cl
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new PaginationSupport(items, totalCount, pageSize, !J<}=G5
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startIndex); m=;0NLs4
return ps; l"9.zPvT<
} R7axm<PR=
}, true); 9e^HTUFbG
} 8z,i/:
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public List findAllByCriteria(final (Uk1Rt*h
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DetachedCriteria detachedCriteria){ |M&i#g<A;
return(List) getHibernateTemplate N~I2~f
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().execute(new HibernateCallback(){ *5KV DOd
publicObject doInHibernate F!v`._]
="%nW3e@
(Session session)throws HibernateException { #'"zyidu
Criteria criteria = :|%dV}j
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detachedCriteria.getExecutableCriteria(session); E+XpgR5
return criteria.list(); `LD#fg*
} m(Hb! RT
}, true); \)H}
} kaSi sjd
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public int getCountByCriteria(final CE :x;!}cd
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DetachedCriteria detachedCriteria){ a%3V<
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Integer count = (Integer) J
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getHibernateTemplate().execute(new HibernateCallback(){ f"^G\
publicObject doInHibernate ^a9v5hu
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(Session session)throws HibernateException { Vs>/q:I
Criteria criteria = ]-
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detachedCriteria.getExecutableCriteria(session); %onUCN<O`
return {/f\lS.5g
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criteria.setProjection(Projections.rowCount B o@B9/ABv
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R`5
()).uniqueResult(); JzhbuWwF-
} K \?b6;ea
}, true); fC!]M hA"i
return count.intValue(); QBi&Q%p iy
} XhF7%KR
} "2cJ'n/L
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用户在web层构造查询条件detachedCriteria,和可选的 L0j&p[(r
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7nh,j <~;2
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PaginationSupport的实例ps。 q%HT)^F9oO
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ps.getItems()得到已分页好的结果集 |T53m;D
ps.getIndexes()得到分页索引的数组 ~b}@*fq
ps.getTotalCount()得到总结果数 ]6wo]nV[P
ps.getStartIndex()当前分页索引 &"bcI7uGT
ps.getNextIndex()下一页索引 'B;aXy/JC
ps.getPreviousIndex()上一页索引 CTu#KJ?j
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?A|8J5EV
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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 79:Wo>C3-
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一下代码重构了。 L,Jl#
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我把原本我的做法也提供出来供大家讨论吧: (<?6X9F:N
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首先,为了实现分页查询,我封装了一个Page类: 5@3[t`n'
java代码: =3rPE"@,[
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/*Created on 2005-4-14*/ pDr%uL
package org.flyware.util.page; r&AX
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/** r3X|*/
* @author Joa G5y>v^&H
* SJY<#_b
*/ %-? :'F!1
publicclass Page { )zK`*Fa
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/** imply if the page has previous page */ <b74L
privateboolean hasPrePage; \VmqK&9
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/** imply if the page has next page */ h>v;1QO9D
privateboolean hasNextPage; 8>.l4:`
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/** the number of every page */ eto3dJ!R
privateint everyPage; y(&JE^GfX
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/** the total page number */ %OW LM
privateint totalPage; ~2xC.DF_N
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/** the number of current page */ +pU\;x
privateint currentPage; a' "4:(L
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/** the begin index of the records by the current YH33E~f
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query */ |ubDudzp
privateint beginIndex; &wR