Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 g'Ft5fQ"o/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6+IOJtj
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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 8E/$nRfOd
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 [8Ub#<]]
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分页支持类: >0+m
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java代码: 5<4njo?k
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package com.javaeye.common.util; L3nHvKA]
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import java.util.List; 8nES=<rz
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publicclass PaginationSupport { 0"u*K n
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publicfinalstaticint PAGESIZE = 30; ^]wm Y
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privateint pageSize = PAGESIZE; _@sqCf%|
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privateList items; 7r"!&P*,
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privateint totalCount; _w+sx5
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privateint[] indexes = newint[0]; VjYfnvE
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privateint startIndex = 0; :@_CQc*yB
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public PaginationSupport(List items, int BAmH2"
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totalCount){ 8XX,(k_b
setPageSize(PAGESIZE); 3KB)\nF#%
setTotalCount(totalCount); G7%Nwe~Y
setItems(items); 0g]ABzTn
setStartIndex(0); lDp5aT;DsM
} ?xK9
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public PaginationSupport(List items, int )^%,\l-!
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totalCount, int startIndex){ tDEpR
setPageSize(PAGESIZE); %~Nf,
setTotalCount(totalCount);
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setItems(items); o,bV.O.W
setStartIndex(startIndex); 7_#v_ A^
} 1P8$z:|~
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public PaginationSupport(List items, int 3zWY%(8t4?
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totalCount, int pageSize, int startIndex){ O|7q,bEm^
setPageSize(pageSize); Vize0fsD
setTotalCount(totalCount); uT]_pKm
setItems(items); 5?9}^s4
setStartIndex(startIndex); Vl^jTX5N
} 5I T'u3V
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publicList getItems(){ s}|IRDpp
return items; *i5&x/ds
} P|HY=RMa
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publicvoid setItems(List items){ + 6r@HK`,t
this.items = items; (O&~*7D*
} XFK$p^qu
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publicint getPageSize(){ woR((K] #G
return pageSize; .s7/bF
} ,vg8iRa
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publicvoid setPageSize(int pageSize){ Y ;&Cmi
this.pageSize = pageSize; Ks7s2 vK^
} vGm;en
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publicint getTotalCount(){ pVbX#3
return totalCount; h3@mN\=h'
} A|RAMO@le
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publicvoid setTotalCount(int totalCount){ kf "cd1
if(totalCount > 0){ A.WJ#1i}E
this.totalCount = totalCount; 1grrb&K
int count = totalCount / =N7N=xY
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pageSize; y"@~5e477$
if(totalCount % pageSize > 0) I|WBT
count++; ]BAF
indexes = newint[count]; / d6mlQS
for(int i = 0; i < count; i++){ ZP%^.wxC
indexes = pageSize * ;'gzRC
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} k(VA5upCs
}else{ zT_{M
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this.totalCount = 0; -pqShDar|
} 'Iu$4xo`[
} OkzfQ
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publicint[] getIndexes(){ #exE~@fy-
return indexes; {_(;&\5
} MIt\[EB
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publicvoid setIndexes(int[] indexes){ PjsQ+5[>
this.indexes = indexes; _V8pDcY
} 1L l@
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publicint getStartIndex(){ u{>5
return startIndex; ,T&B.'cq
} ?]3`WJOj
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publicvoid setStartIndex(int startIndex){ sBRw#xyS
if(totalCount <= 0) [%QJ6
this.startIndex = 0; +;cw<9%0
elseif(startIndex >= totalCount) xTAC&OCk^[
this.startIndex = indexes Q3oVl^q
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[indexes.length - 1]; U8<GD|
elseif(startIndex < 0) $orhY D3gv
this.startIndex = 0; vkBngsS
else{ O 6A:0yM4
this.startIndex = indexes /ebYk-c
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[startIndex / pageSize]; ]Ff&zBJ
} ~^VcTSY@<L
} ~9'VP}\
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publicint getNextIndex(){ Ko -<4wu
int nextIndex = getStartIndex() + T+2?u.{I
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pageSize; *AxKV5[H
if(nextIndex >= totalCount) q"]-CGAa
return getStartIndex(); @~a52'\
else pV>/"K
return nextIndex; o'D6lkf0
} M%B]f2C
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publicint getPreviousIndex(){ <'B`b
int previousIndex = getStartIndex() - wetkmd
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pageSize; 0 ]NsT0M
if(previousIndex < 0) [_H9l)
return0; +o_`k!
else y< 146
return previousIndex; q+LjWZ+O
} p]pFZ";70
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} Vwv O@G7A
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抽象业务类 h!)(R<
java代码: R$w=+%F
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/** JDMaLo
* Created on 2005-7-12 v_G4:tY
*/ F]YPq
package com.javaeye.common.business; z2,rnm)Q
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import java.io.Serializable; 1lx\Pz@ol
import java.util.List; FiFZM
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import org.hibernate.Criteria; -98bX]8
import org.hibernate.HibernateException; 5Pv>`E2^
import org.hibernate.Session; ~%sDQt\S
import org.hibernate.criterion.DetachedCriteria; 12k)Ek9
import org.hibernate.criterion.Projections; Ya,>E@oc
import \w`Il"}V
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org.springframework.orm.hibernate3.HibernateCallback; Lp{l&-uQ
import =>BT]WK>
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org.springframework.orm.hibernate3.support.HibernateDaoS 4\-kzGgmo
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upport; &Cdd
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import com.javaeye.common.util.PaginationSupport; uRUysLIw
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public abstract class AbstractManager extends Lx(Y=
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HibernateDaoSupport { |@Z
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privateboolean cacheQueries = false; Bv/v4(G5g
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privateString queryCacheRegion; dyg1.n#M}
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publicvoid setCacheQueries(boolean k deJB-
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cacheQueries){ {L.0jAwB
this.cacheQueries = cacheQueries; HW{+THNj
} BeP0lZ
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publicvoid setQueryCacheRegion(String o<%Sr*
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queryCacheRegion){ F5EKWP
this.queryCacheRegion = b/2t@VlL
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queryCacheRegion; ~Uga=&
} vbh\uv&
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publicvoid save(finalObject entity){ !o>/gI`
getHibernateTemplate().save(entity); o'Po<I
} 4UG7{[!+
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publicvoid persist(finalObject entity){ wn|Sdp
getHibernateTemplate().save(entity); XB^z' P{-Y
} \}G/F!
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publicvoid update(finalObject entity){ 4.R
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getHibernateTemplate().update(entity); LVO`+:
} .7cQKdvcC
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publicvoid delete(finalObject entity){ _H@S(!
getHibernateTemplate().delete(entity); Jf4D">h
} >'E'Mp.
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publicObject load(finalClass entity, +dIg&}Tr
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finalSerializable id){ qI KVu_
return getHibernateTemplate().load P62g7>B5^
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(entity, id); i!sKL%z}
} L?<V KT
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publicObject get(finalClass entity, bi[vs|
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finalSerializable id){ YV 2T$#7u
return getHibernateTemplate().get 6YYZ S2
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(entity, id); 7$}lkL
} 53@*GXzE
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publicList findAll(finalClass entity){ AfFFu\
return getHibernateTemplate().find("from D+#QQH
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" + entity.getName()); [y64%|m
} qeHb0G
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publicList findByNamedQuery(finalString x>Q\j>^
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namedQuery){ T"XZ[q
return getHibernateTemplate -7$7TD`'7
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().findByNamedQuery(namedQuery); QUwSnotgU
} sHmzwvpLA
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publicList findByNamedQuery(finalString query, +{4ziqYj
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finalObject parameter){ pma'C\b>
return getHibernateTemplate DF P0WXbOE
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().findByNamedQuery(query, parameter); #-Ehg4W
} 3g^_Fq'
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publicList findByNamedQuery(finalString query, ENr\+{{%
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finalObject[] parameters){ Pur~Rz\\
return getHibernateTemplate /*B-y$WQk
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().findByNamedQuery(query, parameters); v&(PM{3o
} v#8{pr
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publicList find(finalString query){ QcU&G*
return getHibernateTemplate().find !Z3iu
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(query); 1 }%vZE2
} >\+c@o[
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publicList find(finalString query, finalObject G0Eqo$W)S
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parameter){ /5b,&
return getHibernateTemplate().find k2(B{x}L
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(query, parameter); ('hr;s=
} k?zw4S
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public PaginationSupport findPageByCriteria Oi+9kk
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(final DetachedCriteria detachedCriteria){ F%Oy4*4
return findPageByCriteria __dSEOGoe
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); `@!4#3H
} U$-Gc[=|
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public PaginationSupport findPageByCriteria >1q
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(final DetachedCriteria detachedCriteria, finalint =BW;n]ls
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startIndex){ P_6JweN
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, vo<'7,
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startIndex); ' b1k0 9'
}
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public PaginationSupport findPageByCriteria Ns
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(final DetachedCriteria detachedCriteria, finalint jMFLd
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pageSize, p8gm=
finalint startIndex){ nD#QC=}
return(PaginationSupport) ,cj531.
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getHibernateTemplate().execute(new HibernateCallback(){ fib#)KE
publicObject doInHibernate d!>.$|b
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(Session session)throws HibernateException { T'C^,,if
Criteria criteria = 'Z;8-1M?O
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detachedCriteria.getExecutableCriteria(session); X0\O3l*j
int totalCount = LKC^Y)6o
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((Integer) criteria.setProjection(Projections.rowCount }KFf
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()).uniqueResult()).intValue(); *n]f) Jc
criteria.setProjection #POVu|Y;h
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List items = kz=Ql|@
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criteria.setFirstResult(startIndex).setMaxResults )(CZK&<
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(pageSize).list(); t_ju[xL5B
PaginationSupport ps = kn5X:@{
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new PaginationSupport(items, totalCount, pageSize, #LU<v
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startIndex); cJ^{iOQ+
return ps; FUTD/y]Lu
} u([|^~H]
}, true); tRC*@>I$
} Dt]N&E#\D
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public List findAllByCriteria(final |J:|56kVZq
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DetachedCriteria detachedCriteria){ r%=} e++^%
return(List) getHibernateTemplate T5<851rH
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().execute(new HibernateCallback(){ PAYS~MnV@3
publicObject doInHibernate ctk~}(1#
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(Session session)throws HibernateException { ]0dj##5tJ
Criteria criteria = ]wxjd
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detachedCriteria.getExecutableCriteria(session); >(.GIR
return criteria.list(); AX{X:L8Ut2
} f\+ E&p.
}, true); .m gm1zz
} 70Z#Ej
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public int getCountByCriteria(final fex<9'e
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DetachedCriteria detachedCriteria){ y]U]b G{
Integer count = (Integer) _A/q bm
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getHibernateTemplate().execute(new HibernateCallback(){ _/c1b>kcso
publicObject doInHibernate kN~:Bh$
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(Session session)throws HibernateException { <6rc8jYz
Criteria criteria = [aS<u`/g|
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detachedCriteria.getExecutableCriteria(session); fFe{oR
return (,`R >Dk
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criteria.setProjection(Projections.rowCount y&&%%3
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()).uniqueResult(); u5Tu~
} T9'd?nw9
}, true); nDU=B.?E{O
return count.intValue(); w\}@+w3b~
} UURYK~$K:
} ,wYA_1$$H
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用户在web层构造查询条件detachedCriteria,和可选的 +Y!
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 VFI\2n`
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PaginationSupport的实例ps。 MBn ZO
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ps.getItems()得到已分页好的结果集 , G2(l
ps.getIndexes()得到分页索引的数组 :9~LYJ
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ps.getTotalCount()得到总结果数 }.k*4Vw#Wt
ps.getStartIndex()当前分页索引 )R^&u`k
ps.getNextIndex()下一页索引 g-LMct8$
ps.getPreviousIndex()上一页索引 UFzC8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .%G>z"Xx
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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 6Z#$(oC
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一下代码重构了。 6o)RsxN eu
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我把原本我的做法也提供出来供大家讨论吧: M(U<H;Csk
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首先,为了实现分页查询,我封装了一个Page类: D k<NlH zp
java代码: 0dW*].Gi:
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/*Created on 2005-4-14*/ "F:V$,mJ
package org.flyware.util.page; (Xl+Zi>\{
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/** 7{lWg x
* @author Joa ?*^HZ~O1
* 8o i{%C&-
*/ VHm.uL_UW
publicclass Page { &3$FkU^F6
* hmoi
/** imply if the page has previous page */ 4Opf[3]
privateboolean hasPrePage; \0n<6^y
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/** imply if the page has next page */ Vg~10Q
privateboolean hasNextPage; H X{K5 +
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/** the number of every page */ ?vP6~$*B
privateint everyPage; "*LQr~k~}
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/** the total page number */ ws<pBC,m
privateint totalPage; .*B@1q
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/** the number of current page */ wGw<z[:f
privateint currentPage; 'Q"Mu
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/** the begin index of the records by the current !u;gGgQF
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query */ T"3:dkQw
privateint beginIndex; !0_/=mA^
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/** The default constructor */ AC*SmQ\>!
public Page(){ PqMu2 e
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} ~^PNMZk
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/** construct the page by everyPage 8g {;o7
* @param everyPage t?H
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* */ mNlbiB
public Page(int everyPage){ TBZhL
this.everyPage = everyPage; 3hVuC1;"
} CfT(a!;Eox
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/** The whole constructor */ i|rC Ga0}
public Page(boolean hasPrePage, boolean hasNextPage, \D1@UyE
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