Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )I{41/_YA
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @jO3+
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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 d/Xbk%`p
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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 2V_C_5)1
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分页支持类: ]K0<DO9
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java代码: V0z.w:-
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package com.javaeye.common.util; B:)9hF?o@
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import java.util.List; \%=\_"^?
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publicclass PaginationSupport { 8s pGDg\g
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publicfinalstaticint PAGESIZE = 30; :}TT1@
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privateint pageSize = PAGESIZE;
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privateList items; KOGbC`TN<
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privateint totalCount; 5#s?rA%u
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privateint[] indexes = newint[0]; Rv
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privateint startIndex = 0; g
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public PaginationSupport(List items, int G`PSb<h\oc
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totalCount){ `o
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setPageSize(PAGESIZE); X{\>TOk
setTotalCount(totalCount); ~PP*k QZlJ
setItems(items); T{d7,.:
setStartIndex(0); $-YS\R\9x
} FiJJe
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public PaginationSupport(List items, int pa Uh+"y>
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totalCount, int startIndex){ B;Ab`UX#t
setPageSize(PAGESIZE); k1i*1Tc
setTotalCount(totalCount); pbKDtqSnz
setItems(items); lb5Y$ZC
setStartIndex(startIndex); |[(4h
} =\`g<0
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public PaginationSupport(List items, int ?Q;8D@
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totalCount, int pageSize, int startIndex){ G*2bYsnhX
setPageSize(pageSize); YOwo\'|=
setTotalCount(totalCount); (o)nN8
setItems(items); .]0B=w* Z
setStartIndex(startIndex); .5|AX6p+^
} q PuxYU
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publicList getItems(){ ]H0BUg
return items; oQI3Yz
} B5*{85p(u
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publicvoid setItems(List items){ [tym~ZZ]_m
this.items = items; OJ\IdUZ
} J!O5`k*.C
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publicint getPageSize(){ v' .:?9
return pageSize; _%w-y(Sqn
} Xg?hh 0s
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publicvoid setPageSize(int pageSize){ k-xh-&
this.pageSize = pageSize; frbKi _1
} ZXljCiNn+\
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publicint getTotalCount(){ GLQ1rT
return totalCount; JDfkm+}uY
} G$XvxJ
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publicvoid setTotalCount(int totalCount){ %s P C3L
if(totalCount > 0){ )+RTA
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this.totalCount = totalCount; 1O*5>dkX;%
int count = totalCount / $wH{snX
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pageSize; ^'!]|^
if(totalCount % pageSize > 0) "8%B
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count++; hH[UIe
indexes = newint[count]; xK 9"t;!C&
for(int i = 0; i < count; i++){ 5s_7P"&H
indexes = pageSize * F2]v]]F!
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} 7SLJLn3d
}else{ Ac'[(
this.totalCount = 0; I8@NQ=UV0
} &1YqPk
} PN[
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publicint[] getIndexes(){ U:m[*
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return indexes; fs+l
}
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publicvoid setIndexes(int[] indexes){ wx nD3
this.indexes = indexes; ^5j|
} /"+YE&>\
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publicint getStartIndex(){ ne] |\]
return startIndex; }GJIM|7^
} Ls )y.u
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publicvoid setStartIndex(int startIndex){ I1yZ7QY
if(totalCount <= 0) LvgNdVJDP|
this.startIndex = 0; [>QV^2'Z
elseif(startIndex >= totalCount) W&ya_iP~C
this.startIndex = indexes ."Wdpf`~
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[indexes.length - 1]; G[n^SEY!
elseif(startIndex < 0) 0"7xCx
this.startIndex = 0; "-GjwB
else{ exrsYo!%
this.startIndex = indexes -FV$Sne
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[startIndex / pageSize]; tp<uN~rTgh
} 3?SofPtc/
} *#-X0}'s
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publicint getNextIndex(){ 4V9DPBh
int nextIndex = getStartIndex() + WL$Ee=
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pageSize; 8rwkux >
if(nextIndex >= totalCount) =G3O7\KmH
return getStartIndex(); x4fl=
else ,o7aIg&_H
return nextIndex; tgK$}#.*
} 9~98v;Z1
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publicint getPreviousIndex(){ <-62m8N|
int previousIndex = getStartIndex() - &S}%)g%Iv9
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pageSize; rTYDa3
if(previousIndex < 0) sc'QNhrW
return0; *t J+!1
else Wc [@,
return previousIndex; a)=WDRk
} Ac;rMwXk#
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} rStfluPL
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抽象业务类 rU<NHFGj4
java代码: s''?:
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/** g\;AU2?p7
* Created on 2005-7-12 3kFSu
*/ <6^MVaD
package com.javaeye.common.business; {WUW.(^]G
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import java.io.Serializable; >FED*C4
import java.util.List; ?#?[6t
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import org.hibernate.Criteria; ktLXL;~X
import org.hibernate.HibernateException; LW6&^S?4{
import org.hibernate.Session; RB<LZHZI
import org.hibernate.criterion.DetachedCriteria; | n5F_RL
import org.hibernate.criterion.Projections; @Aa$k:_
import !]1X0wo\
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org.springframework.orm.hibernate3.HibernateCallback; #R$d6N[H
import k%-_z}:3V
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org.springframework.orm.hibernate3.support.HibernateDaoS _h>S7-X
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upport; uU(G &:@
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import com.javaeye.common.util.PaginationSupport; 6Ug(J$Ouh
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public abstract class AbstractManager extends Li~(kw3
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HibernateDaoSupport { aiVd^(
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privateboolean cacheQueries = false; N1$lG?
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privateString queryCacheRegion; #PUvrA2Zl
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publicvoid setCacheQueries(boolean }R-eQT
= !7k/n';
cacheQueries){ p48M7OV
this.cacheQueries = cacheQueries; !9=hUpRN
} f1MKYM%^x
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publicvoid setQueryCacheRegion(String "3o{@TdU
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queryCacheRegion){ N^7Qn*qt[
this.queryCacheRegion = &No6k~T0:b
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queryCacheRegion; N%N%
} H&jK|]UXoO
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publicvoid save(finalObject entity){ T|^rFaA
getHibernateTemplate().save(entity); jqq96hP,
} 4zuM?Dp
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publicvoid persist(finalObject entity){ lJ.:5$2H
getHibernateTemplate().save(entity); ETvn$ Jdp
} %,f|H :+>u
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publicvoid update(finalObject entity){ h(]aP<49L
getHibernateTemplate().update(entity); Dyv 6K_,
} v}p'vh^8B
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publicvoid delete(finalObject entity){ yO Ed8
getHibernateTemplate().delete(entity); MGpP'G:v
} D /ysS$!{
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publicObject load(finalClass entity, yf`Nh
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finalSerializable id){ {<0=y#@u
return getHibernateTemplate().load i5wXT
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(entity, id); .),ql_sXr
} 19-|.9m(
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publicObject get(finalClass entity, S@i*+&Ot
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finalSerializable id){ =au7'i |6
return getHibernateTemplate().get kBolDPvBG
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(entity, id); x'Pp!
} eh_{-
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publicList findAll(finalClass entity){ ,]HH%/h
return getHibernateTemplate().find("from DM"nxTVre
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" + entity.getName()); tDj~+lmdN
} 1{@f:~ v?
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publicList findByNamedQuery(finalString !K a!f1
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namedQuery){ q\wT[W31@
return getHibernateTemplate t.wB\Kmt\
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().findByNamedQuery(namedQuery); ph\KTLU
} 0>hV?A
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publicList findByNamedQuery(finalString query, $s$j</.q
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finalObject parameter){ d]Y-^&]{]
return getHibernateTemplate 5bU[uT,`6
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().findByNamedQuery(query, parameter); Yw7+wc8R
} ^Wb|Pl
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publicList findByNamedQuery(finalString query, N-*
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finalObject[] parameters){ gBM6{48GF
return getHibernateTemplate dXr=&@1
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().findByNamedQuery(query, parameters); M$&aNt;
} =xwA'D9]
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publicList find(finalString query){ s))L^|6
return getHibernateTemplate().find U~!yGj F
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(query); cHN
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} >C,=elM
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publicList find(finalString query, finalObject hAx#5@*5
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parameter){ +$Q.N{LV
return getHibernateTemplate().find !GJnYDN
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(query, parameter); \-(.cj)?
} ')C%CAYW
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public PaginationSupport findPageByCriteria cRYnQ{$'
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(final DetachedCriteria detachedCriteria){ \hGoD
return findPageByCriteria ^rF{%1 DT
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); MbY?4i00%h
} . ]
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public PaginationSupport findPageByCriteria i=b<Mz7|
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(final DetachedCriteria detachedCriteria, finalint AKWM7fI
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startIndex){ 2c?-_OCy;
return findPageByCriteria jSMvZJX3n
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(detachedCriteria, PaginationSupport.PAGESIZE, +E.}k!y
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startIndex); pfd||Z
} #1-y[w/
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public PaginationSupport findPageByCriteria 5Fh?YS =
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(final DetachedCriteria detachedCriteria, finalint 1&{]jG{#
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pageSize, E]G#"EV!Y
finalint startIndex){ ~!o\uTVr
return(PaginationSupport) ^kg[n908Nw
#H]cb#
getHibernateTemplate().execute(new HibernateCallback(){ cYBv}ylw}R
publicObject doInHibernate 4
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(Session session)throws HibernateException { xw?Mc{w
Criteria criteria = __x2xtrH
q,b6).
detachedCriteria.getExecutableCriteria(session); K9JW&5Q
int totalCount = w!$|IC
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((Integer) criteria.setProjection(Projections.rowCount h\+U+?u
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()).uniqueResult()).intValue(); py9zDWk~
criteria.setProjection k-;%/:Om
qJq49}2
(null); 63hOK
List items = z#qlu=
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criteria.setFirstResult(startIndex).setMaxResults &(H;Bin'
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(pageSize).list(); sTu6KMn
PaginationSupport ps = tvNh@it:F
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new PaginationSupport(items, totalCount, pageSize, wps`2`z
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startIndex); T
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return ps; \@yx;}bdI
} *=]hc@
}, true); 1~!
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} 2&*r1NXBE
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public List findAllByCriteria(final S}=d74(/n
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DetachedCriteria detachedCriteria){ pk&kJ307
return(List) getHibernateTemplate dP8b\H
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().execute(new HibernateCallback(){ ~*-(_<FH
publicObject doInHibernate i:ar{ q
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(Session session)throws HibernateException { XA8{N
Criteria criteria = bZ!*s
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detachedCriteria.getExecutableCriteria(session); 9f
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return criteria.list(); ;XFo:?
} 4k9O6
}, true); f.?p"~!
} o(~QuHOp8>
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public int getCountByCriteria(final %'2DEt??
j{)_&|^{
DetachedCriteria detachedCriteria){ #X&`gDW
Integer count = (Integer) I!IWmU6FN
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getHibernateTemplate().execute(new HibernateCallback(){ gXtyl]K:
publicObject doInHibernate asT*Z"/Q!
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(Session session)throws HibernateException { 9}e`_z
Criteria criteria = rUC@Bf
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detachedCriteria.getExecutableCriteria(session); YGy.39@31
return 7P}&<;5zD
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criteria.setProjection(Projections.rowCount Ns.b8Y
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()).uniqueResult(); EsA)o
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} N(<4nAE
}, true); fVCpG~&t
return count.intValue(); w_-v!s2
} y8T%g(
} m`(5B
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用户在web层构造查询条件detachedCriteria,和可选的 jkd'2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 v=4,kG
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PaginationSupport的实例ps。 zUg-M
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ps.getItems()得到已分页好的结果集 2/.Euf
ps.getIndexes()得到分页索引的数组 =,B44:`r
ps.getTotalCount()得到总结果数 gC-3ghmgS
ps.getStartIndex()当前分页索引 6onFf* m!x
ps.getNextIndex()下一页索引 BbA7X
ps.getPreviousIndex()上一页索引 B%95M|
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 _~f&wkc
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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 3D3/\E#'o
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一下代码重构了。 yyZV/
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我把原本我的做法也提供出来供大家讨论吧: -e H5s3:A
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首先,为了实现分页查询,我封装了一个Page类: OZ2gIK
java代码: 5[Sa7Mk
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/*Created on 2005-4-14*/ HIUB:
package org.flyware.util.page; {ETuaFDM
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/** gkDyWZG B
* @author Joa qx3@]9
* $[5S M>e]
*/ b,]QfC
publicclass Page { 2y/|/IW=
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/** imply if the page has previous page */ V gLnpPOQ
privateboolean hasPrePage; #.|efdsG
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/** imply if the page has next page */ 0fhz7\a^_<
privateboolean hasNextPage; E<u6 js,
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/** the number of every page */ Gh3b*O_,
privateint everyPage; y; LL^:rq
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/** the total page number */ APydZ
privateint totalPage; +C4UM9
.(T*mk*>
/** the number of current page */ #l kv&.)x
privateint currentPage; dQSX&.<c,
b}DxD1*nsI
/** the begin index of the records by the current 4-RzWSFbo`
@J"Gn-f~
query */ 1n+C'P"
privateint beginIndex;
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/** The default constructor */ d~NvS-u7
public Page(){ @edx]H1~^
{C6,h#|pg
} E1 )7gio
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/** construct the page by everyPage L1'R6W~%dN
* @param everyPage M`6rI
* */ ~I'1\1
public Page(int everyPage){ <