Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 m.Ki4NUm
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 mZ~f?{
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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 HM &"2c
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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 @0-vf>e3-
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分页支持类: .qs5xGg#9
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java代码: f"t+r
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package com.javaeye.common.util; ^y[- e9O|
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import java.util.List; gjn1ha"h%.
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publicclass PaginationSupport { "x
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publicfinalstaticint PAGESIZE = 30; wicW9^ik
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privateint pageSize = PAGESIZE; -l?\hmDl
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privateList items; SE6c3
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privateint totalCount; ^/~C\
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privateint[] indexes = newint[0]; ]E^)d|_
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privateint startIndex = 0; r0q?e`nsA
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public PaginationSupport(List items, int iH8V] %
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totalCount){ ~L:H]_8F l
setPageSize(PAGESIZE); =s&ycc;-5}
setTotalCount(totalCount);
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setItems(items); RO[6PlrRN
setStartIndex(0); A=r8_.@2@
} ;cGY
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public PaginationSupport(List items, int yiMqe^zy
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totalCount, int startIndex){ KpT=twcK
setPageSize(PAGESIZE); rp=Y }
setTotalCount(totalCount); pj Md
setItems(items); f<M!L>+M6
setStartIndex(startIndex); r9n:[A&HE
} -Eoq#ULvR
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public PaginationSupport(List items, int eIQ@){lJ-]
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totalCount, int pageSize, int startIndex){ tgY/8&$M
setPageSize(pageSize);
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setTotalCount(totalCount); .mplML0oW
setItems(items); u{S"NEc
setStartIndex(startIndex); " -S@R=bi
} >65\
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publicList getItems(){ 9#
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return items; &Qq|
} 5,?^SK|'x
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publicvoid setItems(List items){ f o idneus
this.items = items; TQth"Cv2:
} 1p8hn!V
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publicint getPageSize(){ "b) hj?
return pageSize; OoQLR
} |)S*RQb\
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publicvoid setPageSize(int pageSize){ a\}`
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this.pageSize = pageSize; *Tr9pq%m
} L~C:1VG5
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publicint getTotalCount(){ <u/(7H
return totalCount; Cv[1HO<
} nPk&/H%5hn
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publicvoid setTotalCount(int totalCount){ &Tg~A9y\
if(totalCount > 0){ AWi+xo|
this.totalCount = totalCount; Kl<NAv%j
int count = totalCount / )KOIf{
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pageSize; nd&i9 l
if(totalCount % pageSize > 0) t9)S^: 0
count++; Nh\o39=
indexes = newint[count]; IyAD>Q^
for(int i = 0; i < count; i++){ =MT'e,T
indexes = pageSize * '$[%x
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} U+zntB
}else{ V[n,fEPBr
this.totalCount = 0; ja6V*CWb
} %M:$ML6b<
} fk!9` p'
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publicint[] getIndexes(){ ]E6r)C
return indexes; x"r,l/gzy
} =}YX I
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publicvoid setIndexes(int[] indexes){ y+KAL{AGK
this.indexes = indexes; uW2 q\
} yCN?kHG
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publicint getStartIndex(){ 1 J}ML}h)
return startIndex; i! gS]?*DH
} 5vJxhBm/
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) Wg2 0H23XW
this.startIndex = 0; '.C#"nY>1
elseif(startIndex >= totalCount) UuC-R)
this.startIndex = indexes VfUHqdg-
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[indexes.length - 1]; RC?vU
elseif(startIndex < 0) nLx|$=W
this.startIndex = 0; xsiJI1/68
else{ Z{gm4YV
this.startIndex = indexes E^$8nqCL:
=-,'LOE
[startIndex / pageSize]; =T\=,B
} wJ7^)tTRF
} ~@(C+ 3,
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publicint getNextIndex(){
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int nextIndex = getStartIndex() + $x,EPRNs
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pageSize; ,HI%ym
if(nextIndex >= totalCount) Io[NN aF|
return getStartIndex(); _3< P(w{
else qDU4W7|T`
return nextIndex; >|yP`m
} p_X{'=SQ1
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publicint getPreviousIndex(){ K/j u=>
int previousIndex = getStartIndex() - xaVn.&Wl
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pageSize; 1z4_QZZ.NG
if(previousIndex < 0) -y{(h%6
return0; pb)kN%
else PG}Roj
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return previousIndex; ~X3x-nAt
} v1Q78P
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} #<Lv&-U<KT
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抽象业务类 .FC+
java代码: V )1.)XC
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/** A^#\=ZBg1
* Created on 2005-7-12 h(<>s#=E
*/ {+nf&5E 6
package com.javaeye.common.business; '5LdiSk
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import java.io.Serializable; 79D~Mau#
import java.util.List; t
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import org.hibernate.Criteria; x\(#
import org.hibernate.HibernateException; ENIg_s4
import org.hibernate.Session; q4&! mDU
import org.hibernate.criterion.DetachedCriteria; A[ncwJ
import org.hibernate.criterion.Projections; ()bQmNqmO=
import u~ipB*Zf
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org.springframework.orm.hibernate3.HibernateCallback; , ?U)mYhI
import NsP=l]
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org.springframework.orm.hibernate3.support.HibernateDaoS PJ0~ymE1~G
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upport; FHw%ynC
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import com.javaeye.common.util.PaginationSupport; yn_f%^!G
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public abstract class AbstractManager extends -grmmE]/
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HibernateDaoSupport { r KUtTj
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privateboolean cacheQueries = false; z k/`Uz
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privateString queryCacheRegion; W"\}##
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publicvoid setCacheQueries(boolean k6&~)7 -f
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cacheQueries){ ]vvA]e
this.cacheQueries = cacheQueries; Sx'oa$J
} Eu'E;*-f
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publicvoid setQueryCacheRegion(String WoN},oT[i
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queryCacheRegion){ `G1"&q,i
this.queryCacheRegion = 8wvHg_U6W
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queryCacheRegion; M,@M5o2u
} m+;U,[%[*E
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publicvoid save(finalObject entity){ ''@Tke3IG6
getHibernateTemplate().save(entity); T` h%=u|D
} &)tiO>B^6
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publicvoid persist(finalObject entity){ 1F,U^O
getHibernateTemplate().save(entity); oo\^}jb
} %%}l[W
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publicvoid update(finalObject entity){ BInSS*L
getHibernateTemplate().update(entity); Y3DqsZ@
} t!Cz;ajNi
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publicvoid delete(finalObject entity){ 4X]/8%]V
getHibernateTemplate().delete(entity); Ja:4EU$Lu
} QUn!&55
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publicObject load(finalClass entity, m;l[flQ~
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finalSerializable id){ npltsK):
return getHibernateTemplate().load 4 H0rS'5d
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(entity, id); 7>y]uT@ar
} v4s4D1}
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publicObject get(finalClass entity, W,6q1
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finalSerializable id){ f&4+-w.:V|
return getHibernateTemplate().get f}(4v1T
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(entity, id); IC'+{3.m8
} Ft11?D
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publicList findAll(finalClass entity){ dY&v(~&;]
return getHibernateTemplate().find("from #~nXAs]Q
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" + entity.getName()); "$farDDoF
} hGY-d}npAJ
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publicList findByNamedQuery(finalString _ikKOU^8
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namedQuery){ ]NTQF/
return getHibernateTemplate !AE;s}v)0{
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().findByNamedQuery(namedQuery); JseKqJ?g
} Jw}t~m3
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publicList findByNamedQuery(finalString query, fVgK6?<8^
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finalObject parameter){ Db|JR
return getHibernateTemplate WUie`p
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().findByNamedQuery(query, parameter); sx=1pnP9`
} 2[`n<R\
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publicList findByNamedQuery(finalString query, 0vfMJzk
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finalObject[] parameters){ ;%2+Tc-7I
return getHibernateTemplate f\=
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().findByNamedQuery(query, parameters); lhYJectJa
} Al*=%nY
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publicList find(finalString query){ '6qH@r4Z<
return getHibernateTemplate().find U.SC,;N^
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(query); )uHat#
} [>?|wQy >=
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publicList find(finalString query, finalObject rhPv{6Z|7
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parameter){ 9)vU/fJ|
return getHibernateTemplate().find 6/L[`n"G
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(query, parameter); Z72%Bv
} c!6v-2ykv
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public PaginationSupport findPageByCriteria 7=fNvES2
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(final DetachedCriteria detachedCriteria){ TDR|*Cs
return findPageByCriteria Q3l>xh
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Z1q<) O1QX
} !%t@wQ]\hG
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public PaginationSupport findPageByCriteria nw/g[/<;
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(final DetachedCriteria detachedCriteria, finalint vo
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startIndex){ .jP|b~
return findPageByCriteria P??P"^hU
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(detachedCriteria, PaginationSupport.PAGESIZE, }|Q\@3&
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startIndex); <(Ar[Rp
} 2
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public PaginationSupport findPageByCriteria ],!}|
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(final DetachedCriteria detachedCriteria, finalint ZKt{3P
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pageSize, -V2`[k
finalint startIndex){ .{t5_,P
return(PaginationSupport) \\R<HuTY
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getHibernateTemplate().execute(new HibernateCallback(){ _X?_|!;J
publicObject doInHibernate [^a7l$fmi
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(Session session)throws HibernateException { k8n9zJ8
Criteria criteria = ECL{`m(#n
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detachedCriteria.getExecutableCriteria(session); 30I-E._F
int totalCount = uYlyU~M:D
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((Integer) criteria.setProjection(Projections.rowCount !sI^Lh,Y
jt6_1^
()).uniqueResult()).intValue(); s~(`~Y4
criteria.setProjection )Az0.}
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(null); Es}`SIe/
List items = H'$H@Kn]-
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criteria.setFirstResult(startIndex).setMaxResults t;3).F
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(pageSize).list(); GE]
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PaginationSupport ps = N\]-/$ z
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new PaginationSupport(items, totalCount, pageSize, <6.`(isph
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startIndex); f\$_^dV
return ps; cY!Pv
} 6:QlHuy0nH
}, true); t; #@t/`
} WS4DzuZZ
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public List findAllByCriteria(final *=O3kUoL
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DetachedCriteria detachedCriteria){ >u0XV "g$
return(List) getHibernateTemplate 4yTgH0(T
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().execute(new HibernateCallback(){ Zonn
publicObject doInHibernate PL31(!`@d
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(Session session)throws HibernateException { H^o_B1
Criteria criteria = #$U/*~m $
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detachedCriteria.getExecutableCriteria(session); W"\`UzOLQ
return criteria.list(); T%"wz3~
} 5sEk rT '
}, true); .*"KCQGOgM
} Z-}A"n
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public int getCountByCriteria(final W4P\HM>2
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DetachedCriteria detachedCriteria){ FD%OG6db];
Integer count = (Integer) 'bH~KK5
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getHibernateTemplate().execute(new HibernateCallback(){ TntTR"6aD
publicObject doInHibernate ZjY?T)WE9
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(Session session)throws HibernateException { u!+;Iy7
Criteria criteria = o)b-fAd@$
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detachedCriteria.getExecutableCriteria(session); V#Y"0l+~
return @|w/`!}9q
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criteria.setProjection(Projections.rowCount
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()).uniqueResult(); H;AMRL o4z
} ]d{lS&PRlg
}, true); `25<;@
return count.intValue(); )3|a_
} LtUw
} q!><:"#[G
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用户在web层构造查询条件detachedCriteria,和可选的 +_*iF5\
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 vq3:N'
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PaginationSupport的实例ps。 QAl4w)F
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ps.getItems()得到已分页好的结果集 kQ2WdpZ/
ps.getIndexes()得到分页索引的数组 <dXeP/1w`
ps.getTotalCount()得到总结果数 I+3=|Vef
ps.getStartIndex()当前分页索引 fX\y/C
ps.getNextIndex()下一页索引 qv:DpK
ps.getPreviousIndex()上一页索引 o1{3[=G
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Ui1s]R
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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 /#t::b+>x
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一下代码重构了。 /&czaAR-
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我把原本我的做法也提供出来供大家讨论吧: >-3>Rjo>
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首先,为了实现分页查询,我封装了一个Page类: sC2NFb-+&
java代码: Pv)^L
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/*Created on 2005-4-14*/ nLANWQk9
package org.flyware.util.page; w|0:0Rc~u
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/** !`W0;0'Zg
* @author Joa c|k(_#\B
* Ff
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*/ LU@1Gol
publicclass Page { f+)LVT8p
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/** imply if the page has previous page */ =E(ed,gH8
privateboolean hasPrePage; oS Ybx:2wo
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/** imply if the page has next page */ zyP/'X_~:
privateboolean hasNextPage; 7.)_H
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/** the number of every page */ *p\fb7Pu_3
privateint everyPage; !4Sd ^"
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/** the total page number */ /Ah'KN|EN
privateint totalPage; %z.d;[Hs
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/** the number of current page */ sint":1FC
privateint currentPage; 'w<^4/L Q
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R
/** the begin index of the records by the current 3Tw9Uc\vT
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query */ O69TU[Vn
privateint beginIndex; ~*^o[~x]\
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/** The default constructor */ z/p^C~|}
public Page(){ Y;E'gP-J
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} i],~tT|P
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/** construct the page by everyPage \F+".X#jh
* @param everyPage Ul 85-p
* */ /L|x3RHs
public Page(int everyPage){ TT#V'r\
this.everyPage = everyPage; 376z~
} lh XD9ed
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/** The whole constructor */ &%(SkL_]
public Page(boolean hasPrePage, boolean hasNextPage, ~,8#\]xR
q @wX=
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int everyPage, int totalPage, &t