Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mkuK$Mj
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 K:q|M?_
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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
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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^^WViVX
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分页支持类: $!7$0WbC
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java代码: S1a6uE
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package com.javaeye.common.util; jK\AVjn
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import java.util.List; Cg3 d
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publicclass PaginationSupport { N
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publicfinalstaticint PAGESIZE = 30; s<{) X$
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privateint pageSize = PAGESIZE; DCKH^J
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privateList items; w5`EJp8MC
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privateint totalCount; x7!gmbMfK'
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privateint[] indexes = newint[0]; 9`td_qh
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privateint startIndex = 0; r2m&z%N&
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public PaginationSupport(List items, int \Vx_$E
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totalCount){ r"!xI
setPageSize(PAGESIZE); dy]ZS<Hz8G
setTotalCount(totalCount); elz0t<V
setItems(items); e2kW,JV/<$
setStartIndex(0); qIwsK\^p
} >%LY0(hY3
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public PaginationSupport(List items, int YySo%\d
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totalCount, int startIndex){ uM,R +)3
setPageSize(PAGESIZE); D2I|Z
setTotalCount(totalCount); 3F32 /_`
setItems(items); ?\$6"c<G
setStartIndex(startIndex); bnZ H
} kS4YxtvB
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public PaginationSupport(List items, int aKintb}n
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totalCount, int pageSize, int startIndex){ L_q3m-x0h
setPageSize(pageSize); &WZ&Tt/)/
setTotalCount(totalCount); 1#9PE(!2
setItems(items); Py#TXzEcC
setStartIndex(startIndex); }#S1!TU
} 4 %V9
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publicList getItems(){ w?Pex]i{
return items; \1hQ7:f;\
} @VQ<X4Za
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publicvoid setItems(List items){ "^)GnK +-
this.items = items; t N4-<6
} k*D8IB
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publicint getPageSize(){ Zv(6VVj
return pageSize; Dus!Ki~8(t
} A0OA7m:~4
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publicvoid setPageSize(int pageSize){ \/b[V3<"
this.pageSize = pageSize; L1f=90
} 33&l.[A"!}
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publicint getTotalCount(){ K0D|p$v
return totalCount; N6`U)=2o>h
} 5H1N]v+
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publicvoid setTotalCount(int totalCount){ w|Ry)[
if(totalCount > 0){ &TL"Hd
this.totalCount = totalCount; HD& Cp
int count = totalCount / C_JO:$\rE
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pageSize; -9;?k{{[T
if(totalCount % pageSize > 0) !2>@:CKX
count++; I9m9`4BK
indexes = newint[count]; 'Lw8l `7
for(int i = 0; i < count; i++){ d]:G#<.
indexes = pageSize * 62MQ+H
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} 9C=*>I27?
}else{ kKjcW` [
this.totalCount = 0; g*`xEb='
} sT "q]
} '$eJATtC
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publicint[] getIndexes(){ Gs,e8ri!
return indexes; ,p /{!BX
} nA{yH}D4
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publicvoid setIndexes(int[] indexes){ 8!HB$vdw7
this.indexes = indexes; Od^Sr4C
} qozvNJm)
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publicint getStartIndex(){ jVZ<i}h0B
return startIndex; @rAV;D%
} r;MFVj{
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publicvoid setStartIndex(int startIndex){ }}ic{931
if(totalCount <= 0) bo(w$&
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this.startIndex = 0; #
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elseif(startIndex >= totalCount) T,jb%uPcE
this.startIndex = indexes tbiM>qxB
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[indexes.length - 1]; I8`$a
elseif(startIndex < 0) XogCq?_m
this.startIndex = 0; &:IcwD&
else{ V0#Ocq,
this.startIndex = indexes So8
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[startIndex / pageSize]; Xx%<rsA>F
} `CC=?E
} yP>025o't
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publicint getNextIndex(){ zH6@v+gb
int nextIndex = getStartIndex() + iP;"-Mj
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pageSize; bk;uKV+<
if(nextIndex >= totalCount) XPD1HN!,LT
return getStartIndex(); y+w,j]
else tl\<:8pI"
return nextIndex; 2<y9xvp
} "}`)s_rt
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publicint getPreviousIndex(){ MpGG}J[y
int previousIndex = getStartIndex() - EG|dN(qh
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pageSize; FKu8R%9xn%
if(previousIndex < 0) YURMXbj
return0; i}P{{kMJ
else <F;+A{M)
return previousIndex; ..+#~3es#y
} KR%WBvv
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} |:JT+a1
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抽象业务类 fFqYRK
java代码: DyiJ4m}kh
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/** <Nqbp
* Created on 2005-7-12
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*/ ;l0dx$w
package com.javaeye.common.business; :op_J!;
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import java.io.Serializable; ]VLseF
import java.util.List; .6azUD4
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import org.hibernate.Criteria; SeDk/}/~e
import org.hibernate.HibernateException; S#y[_C?H
import org.hibernate.Session; 4fC:8\A
import org.hibernate.criterion.DetachedCriteria; T-6<qh
import org.hibernate.criterion.Projections; 9g5h~Ma
import `(0B09~7
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org.springframework.orm.hibernate3.HibernateCallback; &k%>u[Bo
import !p/?IW+
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org.springframework.orm.hibernate3.support.HibernateDaoS ZDbe]9#Xh
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upport; ^zQI_ydG
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import com.javaeye.common.util.PaginationSupport; ~8u *sy
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public abstract class AbstractManager extends ~<n.5q%Z
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HibernateDaoSupport { ; s/<wx-C
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privateboolean cacheQueries = false; > ]^'h
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privateString queryCacheRegion; 71{jedT
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publicvoid setCacheQueries(boolean X$ZVY2
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cacheQueries){ u6ULk<<\
this.cacheQueries = cacheQueries; 0>N6.itOz
} >9dD7FH
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publicvoid setQueryCacheRegion(String \xCCJWek
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queryCacheRegion){ 2.Qz"YDh
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this.queryCacheRegion = '6 F-%
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queryCacheRegion; L!If~6oD(
} nm,LKS7
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publicvoid save(finalObject entity){ _Ns EeKU
getHibernateTemplate().save(entity); jfY7ich
} 5o dT\>Sn
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publicvoid persist(finalObject entity){ Szgo@x$^
getHibernateTemplate().save(entity); M}V!;o<t^
} Mz(Vf1pi%
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publicvoid update(finalObject entity){ ZP<<cyY
getHibernateTemplate().update(entity); LZRg%3.E
} 4V')FGB$
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publicvoid delete(finalObject entity){ DVL-qt\;n
getHibernateTemplate().delete(entity); KkA)p/
} \xkKgI/
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publicObject load(finalClass entity, 56 3mz-
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finalSerializable id){ rGyAzL]
return getHibernateTemplate().load N7+L@CC6T
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(entity, id); YNEwX$)M,B
} v _MQ]X
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publicObject get(finalClass entity, KhHFJo[8sf
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finalSerializable id){ FmL]|~
return getHibernateTemplate().get Pb#M7=J/
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(entity, id); KUAzJ[>
} 69g{oo
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publicList findAll(finalClass entity){ l#'V
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return getHibernateTemplate().find("from HeRi67
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" + entity.getName()); a#YK1n[!
} &]nx^C8V;
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publicList findByNamedQuery(finalString =*2,^j
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namedQuery){ @NiuT%#c
return getHibernateTemplate .-KI,IU
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().findByNamedQuery(namedQuery); -K64J5|b7
} h:
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publicList findByNamedQuery(finalString query, 3e_tT8
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finalObject parameter){ k?+ 7%A]
return getHibernateTemplate [n2B6Px
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().findByNamedQuery(query, parameter); uE-(^u
} D|:'|7l W
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publicList findByNamedQuery(finalString query, #De>EQ%
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finalObject[] parameters){ Joow{75K
return getHibernateTemplate $%y q[$^
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().findByNamedQuery(query, parameters); {q-&!l|
} M.W
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publicList find(finalString query){ _f1o!4ocx
return getHibernateTemplate().find |R`"Zu`
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(query); NJUKH1lIhR
} i}-uK,^
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publicList find(finalString query, finalObject Npp YUY
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parameter){ l5[5Y6c>
return getHibernateTemplate().find Qs6<(zaqkt
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(query, parameter);
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} u,^CFws_
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public PaginationSupport findPageByCriteria +jm,nM9
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(final DetachedCriteria detachedCriteria){ _D '(R
return findPageByCriteria U0x
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); V;M_Y$`Lh
} spEdq}
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public PaginationSupport findPageByCriteria VD;*UkapZx
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(final DetachedCriteria detachedCriteria, finalint :
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startIndex){ 6m?<"y8]
return findPageByCriteria ~4~r
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(detachedCriteria, PaginationSupport.PAGESIZE, 5oG~ Fc
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startIndex); htbE
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} bSw^a{~)
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public PaginationSupport findPageByCriteria [>v1JN
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(final DetachedCriteria detachedCriteria, finalint &/UfXKr
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pageSize, A*DN/lG
finalint startIndex){ 2ul8]=
return(PaginationSupport) aC}\`.Kb
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getHibernateTemplate().execute(new HibernateCallback(){ d?X,od6
publicObject doInHibernate [voZ=+/
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(Session session)throws HibernateException { q~> +x?30
Criteria criteria = k( 0; >)<i
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detachedCriteria.getExecutableCriteria(session); 3zh:~w_
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount =i vlS
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()).uniqueResult()).intValue(); ~!Sd|e:4
criteria.setProjection ZXs,TaU
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(null); D'!JV1Q
List items = 7<WUjK|
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criteria.setFirstResult(startIndex).setMaxResults 3H!]X M
}o:LwxNO
(pageSize).list(); AI3x,rk#
PaginationSupport ps = FUL3@Gb$UV
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new PaginationSupport(items, totalCount, pageSize, *l`yxz@U
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startIndex); g "Du]_,
return ps; L~PiDQr?r
} yJ!26
}, true); #$W5)6ch
} 4eB'mPor
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public List findAllByCriteria(final +H&/C1u
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DetachedCriteria detachedCriteria){ 3?j:M]fR
return(List) getHibernateTemplate -KC@M
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().execute(new HibernateCallback(){ k5K5OpY
publicObject doInHibernate qZ!kVrmg&
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(Session session)throws HibernateException { v CsE|eMP
Criteria criteria = ;N.dzH2yA
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detachedCriteria.getExecutableCriteria(session); =b*GV6b
return criteria.list(); J=Kv-@I>E
} Io<T'K
}, true); pBe1:
} fUf1G{4
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public int getCountByCriteria(final 5)Z=FUupA~
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DetachedCriteria detachedCriteria){
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Integer count = (Integer) !EKt$8W
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate Vp; `!+z"
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(Session session)throws HibernateException { `EgX#
Criteria criteria = #tg\
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detachedCriteria.getExecutableCriteria(session); e=h-}XRC
return ;/V])4=
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criteria.setProjection(Projections.rowCount (t3gNin
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()).uniqueResult(); r{?qvl!q
} ]0<K^OIY
}, true); xKBi".wA
return count.intValue(); `vzMuL;
} A?04,l]y
} PdVY tK%
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用户在web层构造查询条件detachedCriteria,和可选的 XBX`L"0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 bHm/Z Zx
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PaginationSupport的实例ps。 -wH0g^Ed
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ps.getItems()得到已分页好的结果集 lGK7XAx,
ps.getIndexes()得到分页索引的数组 LtwfL^ #
ps.getTotalCount()得到总结果数 C8v
ps.getStartIndex()当前分页索引 zk3\v
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ps.getNextIndex()下一页索引 O0r vr$.
ps.getPreviousIndex()上一页索引 ~Fo2M wE2~
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 pk'd&.
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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 }+S~Ah?(
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一下代码重构了。 BE&8E\w
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我把原本我的做法也提供出来供大家讨论吧: 3&E@#I^],
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首先,为了实现分页查询,我封装了一个Page类: LZG(T$dI
java代码: n(LO`{
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/*Created on 2005-4-14*/ ;H8`^;
package org.flyware.util.page; FeZW S>N
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/** XmwR^
* @author Joa `'r~3kP*NT
* uF3{FYM{I
*/ HnFH|H<Uf
publicclass Page { "g"%7jK
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/** imply if the page has previous page */ h(~of(
privateboolean hasPrePage; o*d (;
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/** imply if the page has next page */ |FaK=e
privateboolean hasNextPage; "5$p=|
3 %r*~#nz
/** the number of every page */ o&k,aCQC
privateint everyPage; Rq",;,0ZJ
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/** the total page number */ Yc)Dx3
privateint totalPage; e50xcf1u
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/** the number of current page */ tqB6:p-%
privateint currentPage; h?ijZHG $
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/** the begin index of the records by the current wUg=jnY
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query */ [*C~BM
privateint beginIndex; |_s,]:
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/** The default constructor */ \ ux{J
public Page(){ XfIsf9
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} l]R7A_|
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/** construct the page by everyPage *[jq&
* @param everyPage 0Nk!.gY
* */ By*YBZ
public Page(int everyPage){ *cXi*7|=
this.everyPage = everyPage; u,=?|M\
} 0,#n_"
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/** The whole constructor */ ;3Z?MQe"NQ
public Page(boolean hasPrePage, boolean hasNextPage, l\m7~
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int everyPage, int totalPage, YoQQ ,
int currentPage, int beginIndex){ r M}o)
this.hasPrePage = hasPrePage; 931GJA~g
this.hasNextPage = hasNextPage; @o<B>$tbu4
this.everyPage = everyPage; PCH$)F4^
this.totalPage = totalPage; (A?w|/bZd
this.currentPage = currentPage; 9*!*n ~
this.beginIndex = beginIndex; O
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} iK5[P
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/** S%G&{5
* @return j(pe6
* Returns the beginIndex. %82:?fq
*/ 0uGTc[^^M
publicint getBeginIndex(){ k
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return beginIndex; #>z !ns
} 4^ 0CHy
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/** ! bwy/A
* @param beginIndex i8*(J-M
* The beginIndex to set. L?Ih;
*/ ?2gXF0+~Y2
publicvoid setBeginIndex(int beginIndex){ SHnMqaq
this.beginIndex = beginIndex; hfvC-f97L
}
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/** @RdNAP_6
* @return 3@0!]z^W
* Returns the currentPage. u0Z MrIJ
*/ w H`GzB"
publicint getCurrentPage(){ p~-)6)We?
return currentPage; Uw)B(;Hy?
} }n,LvA@[0
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/** 6>'>BamX
* @param currentPage TyR@3H
* The currentPage to set. zTn.#-7y
*/
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publicvoid setCurrentPage(int currentPage){ {3Dm/u%=9|
this.currentPage = currentPage; `0 u)/s$
} A`I1G9s
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/** BY$L[U;@T
* @return c'bh`H4
* Returns the everyPage. sei%QE]!/
*/ ?uF3Q)rCk
publicint getEveryPage(){ l5enlYH
return everyPage; !Okl3
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} C5X!H_p
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/** ciCQe]fS
* @param everyPage ~UwqQD1p
* The everyPage to set. NMN&mJsmh
*/ , LqfwA|
publicvoid setEveryPage(int everyPage){ 9G[t
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this.everyPage = everyPage; 8b25D|8l
} 6x16?x
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/** E8aD[j[w
* @return fz+dOIU3\L
* Returns the hasNextPage. C&.Q|S2_
*/ {C%f~j
publicboolean getHasNextPage(){ tR?)C=4,
return hasNextPage; K[q-[q#yc
} \.=,}sV2Z
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/** Et&PzDvU
* @param hasNextPage ;F/w&u.n
* The hasNextPage to set. Z..s /K{
*/ q9nQ/]rkHF
publicvoid setHasNextPage(boolean hasNextPage){ &