Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^=`7]E [p
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mrWPTCD{
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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 {2 l35K=
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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 1c8Nr&Jl
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分页支持类: YbAa@Sq@
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java代码: Wd"<u2
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package com.javaeye.common.util; #$W02L8
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import java.util.List; BV)oF2b:
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publicclass PaginationSupport { y0s=yN_
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publicfinalstaticint PAGESIZE = 30; &JMp)zaI[
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privateint pageSize = PAGESIZE; 8LuM eGs
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privateList items; 3{c6)vR2
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privateint totalCount; =T"R_3[NC
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privateint[] indexes = newint[0]; wNc.z*+O"H
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privateint startIndex = 0; iWu
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public PaginationSupport(List items, int V'b$P2 ?^
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totalCount){ 5<64 C}fE3
setPageSize(PAGESIZE); w{F{7X$^
setTotalCount(totalCount); |ppG*ee
setItems(items); "06t"u<%
setStartIndex(0); I;xSd.-
} {:=sCY!
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public PaginationSupport(List items, int \dAs<${(
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totalCount, int startIndex){ )LC"rSNx%
setPageSize(PAGESIZE); /=5:@
setTotalCount(totalCount); ^]rPda#
setItems(items); |WP}y-Au
setStartIndex(startIndex); Xz,fjKUnN
} Lf0X(tC
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public PaginationSupport(List items, int jD}G9=[$1
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totalCount, int pageSize, int startIndex){ m3T=x =
setPageSize(pageSize); _c!$K#Yl{
setTotalCount(totalCount); xP{)+$n
setItems(items); t;HM
setStartIndex(startIndex); LNNwy:_ !
} XXDLbT'J
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publicList getItems(){ HQkK8'\LP
return items; nh
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} 7q%xF#mK=
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publicvoid setItems(List items){ 52,[dP,g
this.items = items; E.N@qMn~
} X+2uM+
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publicint getPageSize(){ &9Kni/
return pageSize; -UB XWl
} }INj~d<:
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publicvoid setPageSize(int pageSize){ gpw,bV
this.pageSize = pageSize; %6.WGuO
} rdH3!
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publicint getTotalCount(){ J?C#'2/
return totalCount; 6?(yMSKa
} 3N[Rrxe2
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publicvoid setTotalCount(int totalCount){ 8bJj3vr
if(totalCount > 0){ %*
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this.totalCount = totalCount; H\fsyxM7
int count = totalCount / +'|nsIx,
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pageSize; nEt{ltsS0
if(totalCount % pageSize > 0) ;Zm-B]\
count++; h6b(FTC^
indexes = newint[count]; H)k V8wU
for(int i = 0; i < count; i++){ QHXA?nBX
indexes = pageSize * d{J@A;da
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} "&:H }Jd
}else{ xx@[ecW
this.totalCount = 0; i!{A7mo
} ,njlKkFw^Z
} 9OYyR
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publicint[] getIndexes(){ l6*MiX]q
return indexes; ]ZnASlc)
} P$x9Z3d_
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publicvoid setIndexes(int[] indexes){ h% eGtd$n
this.indexes = indexes; I&U.5wf
} Zg%tN#6y
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publicint getStartIndex(){ @>,GCuPrm
return startIndex; VOJ/I Dl 4
} #;[0:jU0
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) 9}wI@
this.startIndex = 0; 43 vF(<r&f
elseif(startIndex >= totalCount) ..kFn!5(g
this.startIndex = indexes +MZI \>
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[indexes.length - 1]; ppo0DC\>
elseif(startIndex < 0) x2sKj"2?@
this.startIndex = 0; 5T%2al,F`
else{ !w}b}+]GB
this.startIndex = indexes ;W T<]
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[startIndex / pageSize]; ;F|#m,2Q-
} km*Y#`{
} hVz] wKP
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publicint getNextIndex(){ 182g6/,
int nextIndex = getStartIndex() + O/U? Wq
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pageSize; Z3yy(D>*
if(nextIndex >= totalCount) UEx13!iFo
return getStartIndex(); 1>uAVPa
else -g."{|
return nextIndex; TQu.jC
} 'ieTt_1.G
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publicint getPreviousIndex(){ cQ]c!G|a4
int previousIndex = getStartIndex() - k'_f?_PBu
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pageSize; aAbA)'G
if(previousIndex < 0) @ x .`z
return0; z4 <_>)p
else Oi'y0S~g
return previousIndex; ==
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} Xt:$H6
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} ?=LT
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抽象业务类 pSb tm74
java代码: 'pT13RFD
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/** =IW!ZN_
* Created on 2005-7-12 ^r-d.1
*/ QJj='+R>
package com.javaeye.common.business; G pI4QzR
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import java.io.Serializable; "P0!cY8r
import java.util.List; }S8aR:'
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import org.hibernate.Criteria; '#yqw%
import org.hibernate.HibernateException; >DUTmJxv
import org.hibernate.Session; n
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import org.hibernate.criterion.DetachedCriteria; 0TaI"/ai
import org.hibernate.criterion.Projections; _
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import n807?FORB
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org.springframework.orm.hibernate3.HibernateCallback; KJV8y"^=Q
import 2F>Y{3&
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org.springframework.orm.hibernate3.support.HibernateDaoS ]\KVA)\
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upport; g5y`XFY
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import com.javaeye.common.util.PaginationSupport; 5q*s_acQ
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public abstract class AbstractManager extends Yb^e7Eug
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HibernateDaoSupport { u178vby;l
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privateboolean cacheQueries = false; i%!<6K6UT
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privateString queryCacheRegion; -yB}(69
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publicvoid setCacheQueries(boolean y%ij)vQY
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cacheQueries){ &BLCP d
this.cacheQueries = cacheQueries; J}&U[ds p
} y~\ujp_5w
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publicvoid setQueryCacheRegion(String {ibu0
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queryCacheRegion){ ; ?f+
this.queryCacheRegion = F$DA/ {.D
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queryCacheRegion; X5YOxMq
} t$(#$Z,RS
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publicvoid save(finalObject entity){ |,p"<a!+{w
getHibernateTemplate().save(entity); W M` 3QJb
} m=sEB8P
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publicvoid persist(finalObject entity){ 2zqaR[C
getHibernateTemplate().save(entity); >STthPO
} 1R3,Z8j'
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publicvoid update(finalObject entity){ #<< el;n
getHibernateTemplate().update(entity); L&DjNu`!9
} 9:4S[mz/hD
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publicvoid delete(finalObject entity){ $*942. =Q
getHibernateTemplate().delete(entity); pdRM%ug
} ?/OF=C#
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publicObject load(finalClass entity, 0t?o6e
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finalSerializable id){ )`rD]0ua;
return getHibernateTemplate().load I4G0!"T+
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(entity, id); 5aizWz
} T8a' 6otc
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publicObject get(finalClass entity, Rb L?(
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finalSerializable id){ r@3-vLI!u
return getHibernateTemplate().get U}5fjY
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(entity, id); Cu8mN B{H
} T4]2R
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publicList findAll(finalClass entity){ B^/MwD>%
return getHibernateTemplate().find("from #zTy7ZS,0
):'wxIVGI
" + entity.getName()); 86OrJdD8
} -y-}g[`
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publicList findByNamedQuery(finalString gZ4'
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namedQuery){ 7S}0Kuk)
return getHibernateTemplate VkFh(Br<{
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().findByNamedQuery(namedQuery); ;&&<zWq3h
} KM wV;r
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publicList findByNamedQuery(finalString query, D+3?p
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finalObject parameter){ U0_)J1Yp
return getHibernateTemplate D_d>A+
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().findByNamedQuery(query, parameter); (U.Go/A#wE
} K>DN6{hnV;
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publicList findByNamedQuery(finalString query, vHf)gi}O|
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finalObject[] parameters){ #"4ioTL2
return getHibernateTemplate -5b|nQuY
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().findByNamedQuery(query, parameters); D6Ad"|Z
} )k=KLQ\b
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publicList find(finalString query){ p-}X=O$
return getHibernateTemplate().find oh8:1E,I
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(query); Ei_~K';
} Qb^G1#r@C
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publicList find(finalString query, finalObject D`JBK?~
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parameter){ MM@,J<
return getHibernateTemplate().find Z6zV 9hn
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(query, parameter); XL n9NBT4K
} !d N[9}
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public PaginationSupport findPageByCriteria /xk7Z
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(final DetachedCriteria detachedCriteria){ "#iJ/vy
return findPageByCriteria _p*9LsN$L
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); mITB\,,G
} @PvO;]]%
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public PaginationSupport findPageByCriteria 'GJB9i+a^
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(final DetachedCriteria detachedCriteria, finalint XYo,5-
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startIndex){ EbILAJ
return findPageByCriteria E%`J=C}
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(detachedCriteria, PaginationSupport.PAGESIZE, 5*%Gh&)
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startIndex); ln82pQD2Y~
} ,0! 2x"Q=
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public PaginationSupport findPageByCriteria cj[b ^Wv:
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(final DetachedCriteria detachedCriteria, finalint `*8}q!.
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pageSize, G}pFy0W\S
finalint startIndex){ {U=J>#@G
return(PaginationSupport) Wzl/ @CPM
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getHibernateTemplate().execute(new HibernateCallback(){ #3rS{4[
publicObject doInHibernate V9oBSP'kt
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(Session session)throws HibernateException { RM|J |R
Criteria criteria = tY)L^.* 7
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detachedCriteria.getExecutableCriteria(session); C^)Imr
int totalCount = z By%=)`
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((Integer) criteria.setProjection(Projections.rowCount w jkh*Y
<<>+z5D+
()).uniqueResult()).intValue(); aRMlE*yW
criteria.setProjection ~ n]5iGz
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(null); *?X&Y8Kf
List items = 9z#8K
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criteria.setFirstResult(startIndex).setMaxResults FHOw ]"#
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(pageSize).list(); dOeM0_o
PaginationSupport ps = >G5aFk
,{0Y:/T'
new PaginationSupport(items, totalCount, pageSize, K3!3[dR*
@Go_5X(
startIndex); juHL$SGC
return ps; Ms!EK
} ws0qwv#
}, true); ?6:qAFw
} sq'm)g
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public List findAllByCriteria(final I0}.!
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DetachedCriteria detachedCriteria){ U<j5s\Y,
return(List) getHibernateTemplate lCU clD
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().execute(new HibernateCallback(){ 6(8F4[D
publicObject doInHibernate SxRJ{m~
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(Session session)throws HibernateException { kk=n&M
Criteria criteria = ZsP ^<
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detachedCriteria.getExecutableCriteria(session); HgQjw!
return criteria.list(); !eyLh&]5
} ;73S;IPR
}, true); FSEf0@O:
} W> pe-
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public int getCountByCriteria(final rRe5Q
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DetachedCriteria detachedCriteria){ +VUkV-kP
Integer count = (Integer) {lds?AuK
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getHibernateTemplate().execute(new HibernateCallback(){ #kW=|8X
publicObject doInHibernate +M=h+3hw](
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(Session session)throws HibernateException { {"wF;*U.V
Criteria criteria = ZG=]b%
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detachedCriteria.getExecutableCriteria(session); SP%X@~d
return :xsZz$
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criteria.setProjection(Projections.rowCount i-CJ{l
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()).uniqueResult(); `LkrG9KV{
} Dmh$@Uu#F
}, true); 1mmL`M1
return count.intValue(); -gs
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} o-8{C0>:
} gNZwD6GMe?
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用户在web层构造查询条件detachedCriteria,和可选的 a OmG, +o
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Al
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PaginationSupport的实例ps。 Gld~GyB\k
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ps.getItems()得到已分页好的结果集 ko}& X=
ps.getIndexes()得到分页索引的数组 ;<FAcR
ps.getTotalCount()得到总结果数 %j&vV>2
ps.getStartIndex()当前分页索引 +-!3ruwSn
ps.getNextIndex()下一页索引 d*6f,z2=
ps.getPreviousIndex()上一页索引 :BxO6@>Xc
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 VD.TosVeWo
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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 g(&cq
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一下代码重构了。 t=7Gfv
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我把原本我的做法也提供出来供大家讨论吧: .<t {saToU
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首先,为了实现分页查询,我封装了一个Page类: ?i<l7
java代码: }%XB*pzQ
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/*Created on 2005-4-14*/ "r6qFxY
package org.flyware.util.page; ]>~.U~
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/** j([b)k=
* @author Joa 5]i#l3")
* !>Nlp,r&~
*/ 'fn}I0Vc
publicclass Page { @*hv|zjs
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/** imply if the page has previous page */ (%R%UkwP9
privateboolean hasPrePage; $j- Fm:ZIA
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/** imply if the page has next page */ P"7` :a
privateboolean hasNextPage; x)?V{YAL
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/** the number of every page */ />xEpR3_A
privateint everyPage; a@? $#>
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/** the total page number */ 8fQ~UcT$
privateint totalPage; O+-+=W
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/** the number of current page */ ](oeMl18R
privateint currentPage; <~|n}&
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/** the begin index of the records by the current *$7^.eHfdd
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query */ Z*Ffdh>*:&
privateint beginIndex; :+YHj)mN
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/** The default constructor */ /,I?"&FWc
public Page(){ u4lM>(3Y}
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} .yF-<Y
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/** construct the page by everyPage MO~T_6
* @param everyPage ywm"{ U?8
* */ 7UBW3{d/u5
public Page(int everyPage){ -F`gRAr-
this.everyPage = everyPage; .x$V~t
} L@MCB-@V
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/** The whole constructor */ uhq6dhhR
public Page(boolean hasPrePage, boolean hasNextPage, t_^cqEr
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int everyPage, int totalPage, -AnJLFY
int currentPage, int beginIndex){ ~%\vX
this.hasPrePage = hasPrePage; ;R
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this.hasNextPage = hasNextPage; tLJ 7tnB
this.everyPage = everyPage; M]V
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this.totalPage = totalPage; @{V`g8P>
this.currentPage = currentPage; 4=q4_ \_T
this.beginIndex = beginIndex; ->|eMV'd
} C^C'!
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/** p!DdX
* @return ~RLjL"
* Returns the beginIndex. pe[huYE
*/ {{A=^rr%C
publicint getBeginIndex(){ nkq{_;xp
return beginIndex; $I`,nN
} (6[<