Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Z fd `Fu
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s=Xg6 D
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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 @+sYwlA~
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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 ;P^}2i[q>[
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分页支持类: jEm=A8q
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java代码: sC_doh_M
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package com.javaeye.common.util; B.}j1Bb
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import java.util.List; x,c\q$8yH
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publicclass PaginationSupport { 2BO"mc<#$
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publicfinalstaticint PAGESIZE = 30; 1aezlDc*
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privateint pageSize = PAGESIZE; v7<r-<I[
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privateList items; bp'\nso/
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privateint totalCount; 'M
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privateint[] indexes = newint[0]; 9O\yIL
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privateint startIndex = 0; @&GY5<&b
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public PaginationSupport(List items, int TVK*l*
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totalCount){ QG5c>Q
setPageSize(PAGESIZE); ,7;euV5X
setTotalCount(totalCount); "Mh}n-oju
setItems(items); vofBS
setStartIndex(0); :H/Rhx=
} $PMD $c
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public PaginationSupport(List items, int =<Ss&p>
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totalCount, int startIndex){ q&esI
setPageSize(PAGESIZE); a``Q}.ST
setTotalCount(totalCount); VqS1n
setItems(items); VP^{-mDph
setStartIndex(startIndex); awSi0*d~
} vb$i00?
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public PaginationSupport(List items, int 7b(r'b@N
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totalCount, int pageSize, int startIndex){ @eP(j@(^
setPageSize(pageSize); {m"I-VF
setTotalCount(totalCount); w}?,N
setItems(items); < fYcON
setStartIndex(startIndex); fz rH}^
} :MGIp%3
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publicList getItems(){ ;oOv~YB7H
return items; 0+k=gO
} )Mh5q&ow
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publicvoid setItems(List items){ ]:Pkh./
this.items = items; 7TA&u'
} 6>[J^k%~w)
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publicint getPageSize(){ .]/k#Hv
return pageSize; ?}No'E1!I
} uCj)7>}v{M
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publicvoid setPageSize(int pageSize){ *Tq7[v{0*|
this.pageSize = pageSize; `eKFs0M.
} '&Tz8.jp~
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publicint getTotalCount(){ 7lAn GP.;
return totalCount; q5.5%W
} \7Fp@ .S3
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publicvoid setTotalCount(int totalCount){ "F?p Y@4
if(totalCount > 0){ |al'_s}I
this.totalCount = totalCount; :!fU+2$`^(
int count = totalCount / W\O.[7JP
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pageSize; 6G:7r [
if(totalCount % pageSize > 0) ;JX2ebx
count++; X + B=?|M
indexes = newint[count]; 2lxA/.f
for(int i = 0; i < count; i++){ Pk^V6-
indexes = pageSize * 3#idXc
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} T8Ye+eP}
}else{ @Z89cTO
this.totalCount = 0; o3.b='HAm
} 87hU#nVYh
} -_f-j
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publicint[] getIndexes(){ G.qjw]Llf
return indexes; J:\O .F#Fi
} 7/bF04~%
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publicvoid setIndexes(int[] indexes){ !~]'&9
this.indexes = indexes; _J0(GuG=~
} ^NrC8,p
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publicint getStartIndex(){ ($[@'?Z1
return startIndex; XZxzw*Y1J
} Wbi12{C
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publicvoid setStartIndex(int startIndex){ <#lNi.?.
if(totalCount <= 0) 6^TWY[z2%
this.startIndex = 0; 6W)#FO`
elseif(startIndex >= totalCount) tA-p!#V<k1
this.startIndex = indexes K?=g
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[indexes.length - 1]; ?IR+OCAA
elseif(startIndex < 0) LP}j0)n
this.startIndex = 0; /[|A(,N}{
else{ ?aU-Y_pMe
this.startIndex = indexes =@.5J'!
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[startIndex / pageSize]; mnM$#%q;%
} =Ct$!uun
} 2XV3f$, H
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publicint getNextIndex(){ VpB+|%@p
int nextIndex = getStartIndex() + *4g:V;L
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pageSize; k'K 1zUBj
if(nextIndex >= totalCount) }Q_ }c9?
return getStartIndex(); ;uqi
else #a!qJeWm0
return nextIndex; K}Lu1:~
} Sp@{5
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publicint getPreviousIndex(){ /?:q9Wy
int previousIndex = getStartIndex() - NJ(H$tB@
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pageSize; CjU?3Ag
if(previousIndex < 0) gm}zF%B"
return0; 6"V86b0)h}
else z_87;y;=
return previousIndex; Uy$?B"Z
} 0lpUn74F
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} yu=(m~KX
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抽象业务类 bYy7Ul6]
java代码: p;LF-R
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/** @;{iCVW
* Created on 2005-7-12 g;!,2,De}
*/ L_fiE3G|>
package com.javaeye.common.business; jn>RE
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import java.io.Serializable; _Zbgmasb
import java.util.List; ]]|vQA^
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import org.hibernate.Criteria; tN&X1
import org.hibernate.HibernateException; ;h7O_|<%
import org.hibernate.Session; <*DP G\6Ma
import org.hibernate.criterion.DetachedCriteria; !{ /AJb
import org.hibernate.criterion.Projections; G4)X~.Fy
import +<n8O~h
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org.springframework.orm.hibernate3.HibernateCallback; P>ZIP*
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import >Q|S#(c
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org.springframework.orm.hibernate3.support.HibernateDaoS ]D|Hq4ug
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upport; 3 ~\S]
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import com.javaeye.common.util.PaginationSupport; (?~*.g!
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public abstract class AbstractManager extends jLreN#:9
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HibernateDaoSupport { _~uYNvmg
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privateboolean cacheQueries = false; G1/
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privateString queryCacheRegion; }G1hB#j
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publicvoid setCacheQueries(boolean j'|`:^
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cacheQueries){ 4AuJ1Z
this.cacheQueries = cacheQueries; C9E@$4*
} Ozs&YZ
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publicvoid setQueryCacheRegion(String R?+:Js/
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queryCacheRegion){ r#/Bz5Jb*
this.queryCacheRegion = C07 U.nzh
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queryCacheRegion; (Kaunp5_`
} B e2yS]U
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publicvoid save(finalObject entity){ IP l]$j>N
getHibernateTemplate().save(entity); VHTr;(]hk
} [7gwJiK
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publicvoid persist(finalObject entity){ Bhw|!Y&%
getHibernateTemplate().save(entity); w1
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} 2^=.jML[
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publicvoid update(finalObject entity){ ]LZ,>v
getHibernateTemplate().update(entity); 1U~yu&
} ~QE- $;
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publicvoid delete(finalObject entity){ ob"yz }
getHibernateTemplate().delete(entity); _hs\"W
} {Aq:Kh`&
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publicObject load(finalClass entity, ,5t h D
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finalSerializable id){ +
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return getHibernateTemplate().load P(Ve'
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(entity, id); xzTF| Z\
} qn|~z@"
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publicObject get(finalClass entity, rty&\u@}
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finalSerializable id){ 41jlfKiOm
return getHibernateTemplate().get 2K$#U|Qi
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(entity, id); APT/z0X>
} :Y2J7p[+
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publicList findAll(finalClass entity){ "N*i!h
return getHibernateTemplate().find("from ad[oor/7|
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" + entity.getName()); c9)5G+
} ,Frdi>7 ~
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publicList findByNamedQuery(finalString "=\@
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namedQuery){ D!CuE7}
return getHibernateTemplate 1rQKHC:|
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().findByNamedQuery(namedQuery); w0 0Ba^W
} !`EhVV8u-_
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publicList findByNamedQuery(finalString query, caC(KK#<
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finalObject parameter){ SHT ^Etri
return getHibernateTemplate <P4*7:jX
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().findByNamedQuery(query, parameter); Qv>rww]
} IYk^eG:;
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publicList findByNamedQuery(finalString query, ;IX*4E'4s
Z* L{;
finalObject[] parameters){ H{nYZOf/
return getHibernateTemplate UAq%Y8KA
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().findByNamedQuery(query, parameters); H.8Vm[W
} 58H%#3Fy
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publicList find(finalString query){ +qzCy/_gd
return getHibernateTemplate().find Yl$Cj>FG
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(query); t?:Q
} V_-{TGKX
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publicList find(finalString query, finalObject 7f\@3r
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parameter){ #cD20t
return getHibernateTemplate().find gaXKP1m^
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(query, parameter); O FCA~sR
} #J<IHNRt
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public PaginationSupport findPageByCriteria &\/b(|>
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(final DetachedCriteria detachedCriteria){ {IpIQ-@l
return findPageByCriteria e=%6\&q
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }./_fFN@
}
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public PaginationSupport findPageByCriteria +|=5zWI/
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(final DetachedCriteria detachedCriteria, finalint wu2C!gyBo
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startIndex){ Vdz(\-}ao
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, U\\nSU
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startIndex); xFY<
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} ~1yMw.04V
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public PaginationSupport findPageByCriteria q4rDAQyPO
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(final DetachedCriteria detachedCriteria, finalint r!7e:p JLO
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pageSize, [Ifhh2
finalint startIndex){ 8xEOR!\!`k
return(PaginationSupport) ;y{VdT
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getHibernateTemplate().execute(new HibernateCallback(){ -=A W. Zo
publicObject doInHibernate ;dh8|ujh
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(Session session)throws HibernateException { "<J%@
Criteria criteria = 0u"/7OU
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detachedCriteria.getExecutableCriteria(session); ]O;Hlty(g
int totalCount = 8{GRrwQ>
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((Integer) criteria.setProjection(Projections.rowCount .V\M/q\Tv
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()).uniqueResult()).intValue(); Hw "UJP
criteria.setProjection H~P"uYKIZ
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(null); Kx;DmwX-
List items = OJ'x>kE
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criteria.setFirstResult(startIndex).setMaxResults h1 D#,
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(pageSize).list(); gAY%VFBP0
PaginationSupport ps = dTV:/QM
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new PaginationSupport(items, totalCount, pageSize, joN}N }U
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startIndex); |= frsf~?
return ps; R;XR?59:.
} dLSnhZ
}, true); B
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} s\`Vr;R:|
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public List findAllByCriteria(final _0rHxh7}q
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DetachedCriteria detachedCriteria){ P9p{j1*;
return(List) getHibernateTemplate g1uqsqYt
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().execute(new HibernateCallback(){ ; YaR|)B
publicObject doInHibernate }bv0~}G4
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(Session session)throws HibernateException { ~Lc>~!!t
Criteria criteria = wnE
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detachedCriteria.getExecutableCriteria(session); 0)8QOTeT
return criteria.list(); ItTIU
} JL9d&7-
}, true); J9LS6~
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} h]94\XQ>$
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public int getCountByCriteria(final k"P2J}4eO
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DetachedCriteria detachedCriteria){ Z w5\{Z0
Integer count = (Integer) Or9@ X=C
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getHibernateTemplate().execute(new HibernateCallback(){ ?CS
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publicObject doInHibernate n/"T7Y\2
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(Session session)throws HibernateException { wE75HE`gW
Criteria criteria = v`hv5wQ
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detachedCriteria.getExecutableCriteria(session); Gc9^Z=
return ~^.&nph
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criteria.setProjection(Projections.rowCount g)'tr
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()).uniqueResult(); Siw9_c
} r2T?LO0N{
}, true); LoG@(g&)
return count.intValue(); Yi[dS`,d
} t.pg;#
} Uc0AsUu}?
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用户在web层构造查询条件detachedCriteria,和可选的 | 4I x2GD
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 S'-<p<;D\B
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PaginationSupport的实例ps。
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ps.getItems()得到已分页好的结果集 +29;T0>a
ps.getIndexes()得到分页索引的数组 Ut-6!kAm
ps.getTotalCount()得到总结果数 >B~jPU
ps.getStartIndex()当前分页索引 *:.0c
ps.getNextIndex()下一页索引 i,")U)b
ps.getPreviousIndex()上一页索引 K23_1-mbe
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 |->y'V
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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 M{kPEl&Z
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一下代码重构了。 F'CUkVC0~P
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我把原本我的做法也提供出来供大家讨论吧: f9- |!]s
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首先,为了实现分页查询,我封装了一个Page类: hqD;<:.
java代码: lO $M6l
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/*Created on 2005-4-14*/ 5,AQ~_,'\
package org.flyware.util.page; ,f?#i%EF&
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/** z3*G(,
* @author Joa =w A< F
* 0v7;ZxD
*/ 2K*-uT#$~
publicclass Page { nv $
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/** imply if the page has previous page */ 9jPb-I-
privateboolean hasPrePage; 2Bjp{)*
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/** imply if the page has next page */ a3c4#'c|D
privateboolean hasNextPage; nnGA_7-t
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/** the number of every page */ u}%&LI`.
privateint everyPage; yL
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/** the total page number */ hTG
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privateint totalPage; pO+1?c43
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/** the number of current page */ h5F'eur
privateint currentPage; }ZmdX^xB
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/** the begin index of the records by the current 1M;)$m:
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query */ ONjc},_
privateint beginIndex; O[L8(+Sn
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/** The default constructor */ c&Zm>Qo[
public Page(){ g?$9~/h :;
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} Ro1' L1:
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/** construct the page by everyPage FoG<$9
* @param everyPage =h_gj >
* */ &\X;t|
public Page(int everyPage){ {H+?DMh
this.everyPage = everyPage; BkZ%0rw%
} KncoIw
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/** The whole constructor */ D1Sl+NOV
public Page(boolean hasPrePage, boolean hasNextPage, 'j3'n0o
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int everyPage, int totalPage, bp$jD
int currentPage, int beginIndex){ O(~Vvoq
this.hasPrePage = hasPrePage; ;:e,C@Fm
this.hasNextPage = hasNextPage; g^C6"rsnl
this.everyPage = everyPage;
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this.totalPage = totalPage; OXacI~C
this.currentPage = currentPage; *(scSC>
this.beginIndex = beginIndex; ]Cz16e&=2
} aBI]' D;
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/** 2>!ykUw^O
* @return XGoy#h
* Returns the beginIndex. zc1Zuco|
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*/ 6+u'Tcb
publicint getBeginIndex(){ d$TW](Bby
return beginIndex; ~JNuy"8
} `?@7 KEl>
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/** Ax^'unfQ:
* @param beginIndex Ji!-G4.n"
* The beginIndex to set. #CS>A#Lk
*/ lX4p'R-h
publicvoid setBeginIndex(int beginIndex){ 2bJFlxEU
this.beginIndex = beginIndex; c'B"Onu@m*
} "n6Y^
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/** 9A_7:V]_
* @return /)I9+s#q9o
* Returns the currentPage. vvM)Rb,
*/ hjG1fgEj
publicint getCurrentPage(){ ,![=_ d
return currentPage; mCGcM^21-x
} uf^:3{1
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/** ?},ItJ#>)q
* @param currentPage uJOW%|ZN`
* The currentPage to set. VL{#.;QQa
*/ `aUp&8{
publicvoid setCurrentPage(int currentPage){ @,MdvR+a
this.currentPage = currentPage; /(V=Um^0
} vOK;l0%
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/** S2R[vB4).
* @return <n\.S
* Returns the everyPage. `g1Oon_
*/ ]1&9~TL
publicint getEveryPage(){ ~{+{p cO}
return everyPage; h2%:;phH
} >.iw8#l
/=@vG Vp6
/** %&Cl@6
* @param everyPage QVW6SY
* The everyPage to set. jEsTw_
*/ MQ*#oVqv
publicvoid setEveryPage(int everyPage){ DH
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this.everyPage = everyPage; S
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} 0'hx w3#
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/** >y9o&D