Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 9cz )f\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 )tvc/)&A}
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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 +[_gyLN<5b
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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 hg4J2m
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分页支持类: [NjajA~z>F
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java代码: w~]}acP
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package com.javaeye.common.util; QU,?}w'?d
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import java.util.List; 3}yraX6r!
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publicclass PaginationSupport { cmae&Atotw
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publicfinalstaticint PAGESIZE = 30; Q6xgLx[
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privateint pageSize = PAGESIZE; S`4e@Z$
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privateList items; 4">84,-N
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privateint totalCount; %$^$'6\77
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privateint[] indexes = newint[0]; 8XgVY9]Qm
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privateint startIndex = 0; R+C+$?4NG
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public PaginationSupport(List items, int E#m76]vkCU
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totalCount){ jjNxatAN
setPageSize(PAGESIZE); Fv<]mu
setTotalCount(totalCount); O$YJku
setItems(items); /\Jc:v#Q
setStartIndex(0); zC[i <'h!T
} *pmoLiuB>
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public PaginationSupport(List items, int RiwEuY
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totalCount, int startIndex){ k:@a[qnY
setPageSize(PAGESIZE); _ak.G=
setTotalCount(totalCount); X*(gT1"t
setItems(items); "~B~{ _<j
setStartIndex(startIndex); hn*}5!^
}
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public PaginationSupport(List items, int 9N`+ O
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totalCount, int pageSize, int startIndex){ 2&3eAJC
setPageSize(pageSize); 2X
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setTotalCount(totalCount); |E>v~qD8I
setItems(items); ot&j HS'
setStartIndex(startIndex); +ytT)S
} \k2C 5f
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publicList getItems(){ $fq-wl-=
return items; e)fJd*P
} [J[ysW})W
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publicvoid setItems(List items){ eUGmns
this.items = items; BZnp
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} b6rzHnl{
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publicint getPageSize(){ 2`q^Q
return pageSize; MZ >0K
} R(n0!h4
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publicvoid setPageSize(int pageSize){ ePIly)=X
this.pageSize = pageSize; N7Z(lI|a;
} S]#=ES'^/
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publicint getTotalCount(){ qW` XA
return totalCount; |yId6v
} A1=$kzw{UH
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publicvoid setTotalCount(int totalCount){ &})4?5
if(totalCount > 0){ ?$`1%Y9
this.totalCount = totalCount; ,&O:/|c E
int count = totalCount / lhW#IiX
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pageSize; |n-a\
if(totalCount % pageSize > 0) 9
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count++; %3@RZe
indexes = newint[count]; ?L~=Z\H
for(int i = 0; i < count; i++){ t0AqGrn
indexes = pageSize * =":V
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i; L;(3u'
} W0r5D9k
}else{ 6m;wO r
this.totalCount = 0; DlQ[}5STF
} ;MdK3c
} F6neG~Y
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publicint[] getIndexes(){ hnfrnYH
return indexes; RE*S7[ge
} L}sm R,
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publicvoid setIndexes(int[] indexes){ fAA@ziKg
this.indexes = indexes; q}76aa0e
} f^yLwRUD
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publicint getStartIndex(){ /EAQ.vxI
return startIndex; BOl$UJ|K
} S r#fyr
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publicvoid setStartIndex(int startIndex){ URzE+8m^
if(totalCount <= 0) hcqmjqJ
this.startIndex = 0; Zv7$epDUz
elseif(startIndex >= totalCount) 0_xcrM
this.startIndex = indexes 3E2.v5*
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[indexes.length - 1]; #p9z#kin
elseif(startIndex < 0) @BQBNGR 1
this.startIndex = 0; $!3t$-TSD
else{ ,9j:h)ks?
this.startIndex = indexes W&re;?Z{ke
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[startIndex / pageSize]; R"kE5:
} l$_+WC*wp
} 2n+XML
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publicint getNextIndex(){ Dp |FyP_w
int nextIndex = getStartIndex() + OU3+SYM
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pageSize; 2]3Jb{8FI>
if(nextIndex >= totalCount) BNm va
return getStartIndex(); GpQF* x
else 9PfU'm|h
return nextIndex; %IXW|mi
} A-`J!xj#/
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publicint getPreviousIndex(){ h}<ZZ
int previousIndex = getStartIndex() - KIl.?_61O
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pageSize; Y_YIJ@
if(previousIndex < 0) c89vx 9
return0; +rO<'H:umJ
else SpiC0
return previousIndex; ~TR|Pv
} oi4Wxcj
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} &_hCsTkt
import java.io.Serializable; %"fKZ
import java.util.List; ^{bEq\5&
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import org.hibernate.Criteria; Sylsp%A
import org.hibernate.HibernateException; ebK
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import org.hibernate.Session; hkI);M+@6
import org.hibernate.criterion.DetachedCriteria; CxQ,yd;>
import org.hibernate.criterion.Projections; 6^u(PzlA|~
import BQg]$Tr?
8QBL:7<
org.springframework.orm.hibernate3.HibernateCallback; )KQum`pO
import X6 cb#s0|
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org.springframework.orm.hibernate3.support.HibernateDaoS ^`?>
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upport; 1`\kXaG
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import com.javaeye.common.util.PaginationSupport; )zV5KC{{
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public abstract class AbstractManager extends 5C?1`-&65V
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HibernateDaoSupport { W7"sWaOhW
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privateboolean cacheQueries = false; [G/X
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privateString queryCacheRegion; ]Jqe)o
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publicvoid setCacheQueries(boolean TD7ONa-,
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cacheQueries){ `<d>C}9
this.cacheQueries = cacheQueries; ic#drpl,
} VRt*!v<")
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publicvoid setQueryCacheRegion(String JK`P
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queryCacheRegion){ m
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this.queryCacheRegion = cpV i9]
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queryCacheRegion; =
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} u'p J9>sC
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publicvoid save(finalObject entity){ 4{KsCd)
getHibernateTemplate().save(entity); lOui{QU
} }d(6N&;"zN
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publicvoid persist(finalObject entity){ =qRVKz
getHibernateTemplate().save(entity); Xc^~|%+
} i}19$x.D`
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publicvoid update(finalObject entity){ xjN~Y D:
getHibernateTemplate().update(entity); |.A>0-']M
} hj4Rr(T
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publicvoid delete(finalObject entity){ C0RwW??t
getHibernateTemplate().delete(entity); >. Y~F(
} 5z_)
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publicObject load(finalClass entity, %#,BvQz~
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finalSerializable id){ )zN
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return getHibernateTemplate().load |zMQe}R@%
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(entity, id); 'SmdU1]4BD
} 5IMH G%W7
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publicObject get(finalClass entity, AZa3!e/1
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finalSerializable id){ JI&>w-~D
return getHibernateTemplate().get KJd;c.
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(entity, id); -n9e-0
} VV
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publicList findAll(finalClass entity){ {x8`gP\H
return getHibernateTemplate().find("from j!s&yHE1
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" + entity.getName()); t`AD9
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} '.=Z2O3p
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publicList findByNamedQuery(finalString &[YG\8sxWa
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namedQuery){ \;3r
return getHibernateTemplate c|7Pnx%gT
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().findByNamedQuery(namedQuery); ?o4&cCFOE
} & zG=
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publicList findByNamedQuery(finalString query, oVu>jO:.
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finalObject parameter){ Rww KPE
return getHibernateTemplate /EC m
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().findByNamedQuery(query, parameter); eN$~@'w
} IOA{lN6
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publicList findByNamedQuery(finalString query, ecHy. 7H
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finalObject[] parameters){ Bq!P.%6p4
return getHibernateTemplate 65AOFH
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().findByNamedQuery(query, parameters); tly:$;K
} Xbz}pAnj
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publicList find(finalString query){ $]Q_x?
return getHibernateTemplate().find os2yiF",
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(query); JK1b68n
} vH?/YhH|
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publicList find(finalString query, finalObject 5'o.v^l
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parameter){ sOHh&e
return getHibernateTemplate().find B^6P6,
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(query, parameter); 9`b*Y*d
} [X-Q{c4
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public PaginationSupport findPageByCriteria Kkd7D_bZ*
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(final DetachedCriteria detachedCriteria){ /aK },+
return findPageByCriteria >LW9$[H
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]$z~;\ T
} sG\=_-"v(
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public PaginationSupport findPageByCriteria :cOwTW?Fj
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(final DetachedCriteria detachedCriteria, finalint 5Wn6a$^
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startIndex){ Tp9LBF
return findPageByCriteria {2V=BDS|?K
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(detachedCriteria, PaginationSupport.PAGESIZE, :}E*u^v K
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startIndex); $+?6U
} 1z8.wdWJ}
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public PaginationSupport findPageByCriteria K<V(h#(.@
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(final DetachedCriteria detachedCriteria, finalint P{);$e+b~
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pageSize, 0ai4%=d-
finalint startIndex){ ,@<-h* m
return(PaginationSupport) Tvk= NJ
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getHibernateTemplate().execute(new HibernateCallback(){ hR. EZ|.
publicObject doInHibernate \ 0:ITz
t);5Cw_
(Session session)throws HibernateException { Z-:$)0f
Criteria criteria = A@`C<O ^
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detachedCriteria.getExecutableCriteria(session); dkCSqNFL)
int totalCount = (spX3n%p
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((Integer) criteria.setProjection(Projections.rowCount uD. 0?*_
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()).uniqueResult()).intValue(); <nIU]}q
criteria.setProjection n+xM))
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(null); J\2F%kBej?
List items = |z5olu$gVc
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criteria.setFirstResult(startIndex).setMaxResults +LrW#K;
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(pageSize).list(); ib&
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PaginationSupport ps = )m6=_q5@o
}
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new PaginationSupport(items, totalCount, pageSize, hI/p9
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startIndex); Xst&QKU
return ps; 3fBq~ Q
} J,jl(=G
}, true); S$V'_
} :<nL9y jt
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public List findAllByCriteria(final I|BLAm6j
)Q9J,
DetachedCriteria detachedCriteria){ KxiZx I
return(List) getHibernateTemplate qf
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().execute(new HibernateCallback(){ A(<-
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publicObject doInHibernate &4DvZq=
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(Session session)throws HibernateException { n)
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Criteria criteria = J&h 3,
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detachedCriteria.getExecutableCriteria(session); +>/Q+nh
return criteria.list(); y*_g1q$
} EMJ}tvL0Tp
}, true); _pk=IHGsB
} 1eKJ46W
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public int getCountByCriteria(final J2yq|n?2gq
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DetachedCriteria detachedCriteria){ e3',? 5j
Integer count = (Integer) NW^}u~-f
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getHibernateTemplate().execute(new HibernateCallback(){ E-n!3RQ(w
publicObject doInHibernate cj5pI?@e)
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(Session session)throws HibernateException { %K?~$;Z.
Criteria criteria = \5X34'7
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detachedCriteria.getExecutableCriteria(session); :90DS_4
return iSHNt0Nl
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criteria.setProjection(Projections.rowCount }|Cw]GW
Jtc?p{
()).uniqueResult(); `[Kh[|
} h&[!CtPm
}, true); >}_c<`:
return count.intValue(); #& Rx(
} ^Fy)
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} <@e6zQG
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用户在web层构造查询条件detachedCriteria,和可选的 # P18vK5
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Hm1C|Qb
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PaginationSupport的实例ps。 u=k\]W-
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ps.getItems()得到已分页好的结果集 C6Dq7~{B
ps.getIndexes()得到分页索引的数组 7ug mZO}lL
ps.getTotalCount()得到总结果数 UV@<55)K
ps.getStartIndex()当前分页索引 ,_P(!7Z8
ps.getNextIndex()下一页索引 }evc]?1(
ps.getPreviousIndex()上一页索引 cb|`)"<HN
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ff%m.A8d,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 &Lk@Xq1
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一下代码重构了。 )bPwB.} kq
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我把原本我的做法也提供出来供大家讨论吧: <f8@Qij
.#rI9op
首先,为了实现分页查询,我封装了一个Page类: ||9f@9
java代码: LP#CA^*S
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/*Created on 2005-4-14*/ 75I*&Wl
package org.flyware.util.page; ~O|j*T
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/** |'Ve75 W6u
* @author Joa lT1*e(I
* e>sr)M
*/ WNlWigwYl
publicclass Page { qd!$ nr
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/** imply if the page has previous page */ LTBqXh
privateboolean hasPrePage; k&yy_r
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/** imply if the page has next page */ 9FH=Jp
privateboolean hasNextPage; j%~UU0(J
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/** the number of every page */ /rKrnxw
privateint everyPage; {lx^57v
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/** the total page number */ `'+[Y;s_
privateint totalPage; ;l}TUo
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/** the number of current page */ u+XZdV
privateint currentPage; /!jn$4fd:
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/** the begin index of the records by the current Tet,mzVuu
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query */ cnhYrX^
privateint beginIndex; G)'cd D1
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/** The default constructor */ A%%WPBk{O
public Page(){ Wa,[#H
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} 4*F+-fu
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/** construct the page by everyPage LD]XN'?"W
* @param everyPage jNrGsIY$
* */ AGPZd9
public Page(int everyPage){ o`h F1*yp
this.everyPage = everyPage; =(.HO:#
} 6
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/** The whole constructor */ fu\M2"e
public Page(boolean hasPrePage, boolean hasNextPage, .i@e6JE~;
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int everyPage, int totalPage, S : 9zz
int currentPage, int beginIndex){ 6W#M[0
this.hasPrePage = hasPrePage; 5
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this.hasNextPage = hasNextPage; 4}fG{Bk
this.everyPage = everyPage; ks
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this.totalPage = totalPage; o!\Vk~Vi&
this.currentPage = currentPage; sq-[<ryk
this.beginIndex = beginIndex; <Cn-MOoM
} a&wl-
dhsQfWg#}
/** <E!M<!h
* @return @<AyCaU`.
* Returns the beginIndex. 5A:b
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*/ ^Shz[=fd
publicint getBeginIndex(){ !);'Bk9o
return beginIndex; q\[f$==p
} |V%Qp5 XJ
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/** +hV7o!WxC
* @param beginIndex |4ONGU*`E
* The beginIndex to set. 5Y_)%u
*/ YYZE-{ %
publicvoid setBeginIndex(int beginIndex){ 7p@qzE
this.beginIndex = beginIndex; :a[L-lr`e
} ;~#rdL
f9X*bEl9;`
/** Z&/bp 1
* @return \ C~Y
* Returns the currentPage. %Nzg~ZPbmT
*/ 8u!!a^F
publicint getCurrentPage(){ ,*}SfCon
return currentPage; AQQeLdTq
} W;eHDQ|
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/** _<yJQ|[z~i
* @param currentPage Qt+ K,LY
* The currentPage to set. Z Z\,iT
*/ |!aMj8i2
publicvoid setCurrentPage(int currentPage){ q1.w8$
this.currentPage = currentPage; K8ecSs}}J
} D42Bm&JocO
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/** &C`t(e
* @return 27<~m=`}d
* Returns the everyPage. ,mx>)}l95
*/ #9F=+[L
publicint getEveryPage(){ 4ac2^`
return everyPage; soRt<