Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 SA{5A 1
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b5W(}ka+
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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 } ^WmCX2a
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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 {Z#=ppvs
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分页支持类: O |*-J
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java代码: Tb!jIe
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package com.javaeye.common.util; 5RR4jX]
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import java.util.List; r tH
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publicclass PaginationSupport { ,OBJ>_5
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publicfinalstaticint PAGESIZE = 30; cg^=F_h
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privateint pageSize = PAGESIZE; @j=rSS
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privateList items; f}7/UGd
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privateint totalCount; T}K@ykT
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privateint[] indexes = newint[0]; VTK +aI
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privateint startIndex = 0; -GYJ)f
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public PaginationSupport(List items, int c N~F32<
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totalCount){ 15M!erT
setPageSize(PAGESIZE); b ; U
setTotalCount(totalCount); |};-.}u^`h
setItems(items); a'?V:3 ]
setStartIndex(0); !H~PF*,hY
} f*Yr*yC
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public PaginationSupport(List items, int "]U_o<V
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totalCount, int startIndex){ 4c@_u8
setPageSize(PAGESIZE); VCa`|S?2
setTotalCount(totalCount); YD] :3!MI
setItems(items); +$#ytvDy
setStartIndex(startIndex); "-g5$v$de
} ?7TuE!!M
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public PaginationSupport(List items, int E6fs&
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totalCount, int pageSize, int startIndex){ S.!K
setPageSize(pageSize); jz,Gj}3;
setTotalCount(totalCount); zh9B8r)C
setItems(items); SDko#
setStartIndex(startIndex);
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} a!\^O).pA
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publicList getItems(){ S+GW}?!
return items; /hAy1V6
} 3 V$
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publicvoid setItems(List items){ DtkOb,wY
this.items = items; hpo*5Va
} lA n^)EL
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publicint getPageSize(){ TbgIr
return pageSize; U+:Mu]97
} [E9)Da_)i
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publicvoid setPageSize(int pageSize){ #Ht;5p>5
this.pageSize = pageSize; NGmXF_kqN
} o':K4r;
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publicint getTotalCount(){ &<t`EI];)4
return totalCount; E6#")2C~
} lfqsoIn;
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publicvoid setTotalCount(int totalCount){ p%IVWeZnx
if(totalCount > 0){ 9b)'vr*Hy7
this.totalCount = totalCount; fk\hrVP
int count = totalCount / jRhRw;
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pageSize; ESni r6HoU
if(totalCount % pageSize > 0) Vn?|\3KY
count++; 69N8COLB
indexes = newint[count]; >Y;[+#H[
for(int i = 0; i < count; i++){ ~z7Fz"o<
indexes = pageSize * B
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i; -gpHg
} M\r=i>(cu
}else{ <=@6UPsn2
this.totalCount = 0; Xw&vi\*m
} QsyM[; \j:
} m.c2y6<=
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publicint[] getIndexes(){ :b<<
return indexes; yDAvl+
} 6NGQU%Hd
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publicvoid setIndexes(int[] indexes){ )TwA?kj
this.indexes = indexes; yXBWu=w3`O
} RSIhZYA
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publicint getStartIndex(){ $"fO/8Ex
return startIndex; j){0>O.V
} PKYm{wO-
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publicvoid setStartIndex(int startIndex){ fDwqu.K
if(totalCount <= 0) YZz8xtM<2
this.startIndex = 0; !jRs5{n^Ol
elseif(startIndex >= totalCount) [>|6qY$D
this.startIndex = indexes Zz! yv(e)H
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[indexes.length - 1]; 6&,9=(:J&R
elseif(startIndex < 0) ~>rnq7j
this.startIndex = 0; ;ApldoMi
else{ % E8s>D
this.startIndex = indexes V@\A<q%jTs
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[startIndex / pageSize]; Pl&x6\zL
} dl+:u}9M$
} #xt-65^
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publicint getNextIndex(){ *yN#q>1
int nextIndex = getStartIndex() + D9\ E kX
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pageSize; 8jz7t:0
if(nextIndex >= totalCount) 2E@g#:3
return getStartIndex(); A4Tjfc,rx9
else ?F9c6 $|
return nextIndex; OD).kP}s^
} EgTj
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publicint getPreviousIndex(){ QQQN}!xPj
int previousIndex = getStartIndex() - v[<;z(7Qk
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pageSize; !XT2'6nu
if(previousIndex < 0) B X Et]+Q
return0; )u.%ycfeV
else 2]+f<Z[/
return previousIndex; !~te&ccPE
} .{"wliC2
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} _o?[0E
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抽象业务类 5N$O
java代码: 4td9=dNA+l
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/** D4PjE@D"H
* Created on 2005-7-12 AIt;~x
*/ f#
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package com.javaeye.common.business; Ummoph7_@
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import java.io.Serializable; isor%R!
import java.util.List; E$s?)
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import org.hibernate.Criteria; >44,Dp]
import org.hibernate.HibernateException; <O4W!UVg
import org.hibernate.Session; a+P^?N
import org.hibernate.criterion.DetachedCriteria; !z"nJC
import org.hibernate.criterion.Projections; Kk 6i
import Sw~L
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org.springframework.orm.hibernate3.HibernateCallback; y#-~L-J_R
import HA3d9`
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org.springframework.orm.hibernate3.support.HibernateDaoS 6yedl0@wa!
C ,[q#D4
upport; B\6%.R
ejlau#8"
import com.javaeye.common.util.PaginationSupport; aThvq%;
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public abstract class AbstractManager extends =90)=Pxd
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HibernateDaoSupport { +/!y#&C&*
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privateboolean cacheQueries = false; k;!}nQ&
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privateString queryCacheRegion; Sv[$.^mb
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publicvoid setCacheQueries(boolean )X'ln
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cacheQueries){ q;9OqArq
this.cacheQueries = cacheQueries; m" c6^)U
} h[r)HX0hA
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publicvoid setQueryCacheRegion(String P7
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queryCacheRegion){ $im6v
this.queryCacheRegion = $(&+NJ$U$
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queryCacheRegion; :\"g}AX
} R|R3Ob.e
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publicvoid save(finalObject entity){ tW"s^r=95
getHibernateTemplate().save(entity); ? io,8
} "rR$2`v"
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publicvoid persist(finalObject entity){ >o!5)\F
getHibernateTemplate().save(entity);
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} ad`=A V ]
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publicvoid update(finalObject entity){ D<(VP{,G
getHibernateTemplate().update(entity); xZ>@wBQ
} JeU1r-i
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publicvoid delete(finalObject entity){ :0(:}V3 z\
getHibernateTemplate().delete(entity); \vp^[,SI
} y.?Q
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publicObject load(finalClass entity, Z]=9=S|
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finalSerializable id){ js)I%Z
return getHibernateTemplate().load 8t1,_,2'
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(entity, id); {#H'K*j{
} ;#S4$wISw`
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publicObject get(finalClass entity, ~0Xx]
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finalSerializable id){ onF?;>[
return getHibernateTemplate().get KAm$^N5
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(entity, id); uG7ll5Yy
} 'cvc\=p
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publicList findAll(finalClass entity){ ~A-VgBbU>_
return getHibernateTemplate().find("from o3>D~9
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" + entity.getName()); 6cbIs_g
} a~O](/+p;
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publicList findByNamedQuery(finalString fg~9{1B
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namedQuery){ X1\ao[t<;c
return getHibernateTemplate GM>Ms!Y
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().findByNamedQuery(namedQuery); HD9+4~8
} i0*6o3h
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publicList findByNamedQuery(finalString query, >y^zagC*
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finalObject parameter){ BZ>,Qh!J
return getHibernateTemplate >}>cJh6
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().findByNamedQuery(query, parameter); ,: 4+hJ<q
} $_b^p=
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publicList findByNamedQuery(finalString query, 0vi\o`**Mj
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finalObject[] parameters){ =%$BFg1a(
return getHibernateTemplate 50^T\u
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().findByNamedQuery(query, parameters); `=rDB7!$yL
} %2`geN<
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publicList find(finalString query){ %[7<GcWl
return getHibernateTemplate().find CHNIL^B
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(query); `]\:%+-
} sH{4 .tw
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publicList find(finalString query, finalObject pG9qD2Cf
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parameter){ /\|AHM
return getHibernateTemplate().find EHY}gG)
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(query, parameter); 3tIno!|
} [^GXHE=
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public PaginationSupport findPageByCriteria )k'4]=d
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(final DetachedCriteria detachedCriteria){ p:9^46N@
return findPageByCriteria qGPIKu
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ;fnE"}
} \" W_\&X
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public PaginationSupport findPageByCriteria p^ojhrr
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(final DetachedCriteria detachedCriteria, finalint )>~d`_$dt
( [m[<
startIndex){ )/2J|LxS
return findPageByCriteria 2or!v^^u
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(detachedCriteria, PaginationSupport.PAGESIZE, bTN0 n
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startIndex); TB
} /WX
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public PaginationSupport findPageByCriteria BavGirCp
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(final DetachedCriteria detachedCriteria, finalint Gv uX"J
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pageSize, fPLi8`r
finalint startIndex){ v<wR`7xG
return(PaginationSupport) (fJ.o-LQ
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getHibernateTemplate().execute(new HibernateCallback(){ =$t
publicObject doInHibernate ;$= GrR
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(Session session)throws HibernateException { +f- E8q
Criteria criteria = Zc Y* TGx
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detachedCriteria.getExecutableCriteria(session); WOaj_o
int totalCount = ahJu+y
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((Integer) criteria.setProjection(Projections.rowCount -WX{y Ci
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()).uniqueResult()).intValue(); `LID*uD;_
criteria.setProjection yA#-}Y|]b
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(null); 6q!smM
List items = qr~=S
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criteria.setFirstResult(startIndex).setMaxResults &InMI#0mV
d].(x)|st
(pageSize).list(); 8aSH0dX
PaginationSupport ps = (VxWa#P
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new PaginationSupport(items, totalCount, pageSize, xep!.k x
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startIndex); 9J!@,Zsh
return ps; itg
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} <&$:$_ah
}, true); HAi'0%"
} uWSfr(loX
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public List findAllByCriteria(final [H!8m7i;
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DetachedCriteria detachedCriteria){ bz=B&YR
return(List) getHibernateTemplate l]GUQcN=
nd 5w|83
().execute(new HibernateCallback(){ @zHTKi`
publicObject doInHibernate pxs#OP
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(Session session)throws HibernateException { F5#P{zk|
Criteria criteria = ?oc#$fcQ~
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detachedCriteria.getExecutableCriteria(session); V+M=@Pvp9
return criteria.list(); _qPd)V6yb
} QE.a2
}
}, true); \Q5Jg
} }4; \sY
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public int getCountByCriteria(final ?1f(@
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DetachedCriteria detachedCriteria){ *)2&gQ&%+
Integer count = (Integer) #hOAG_a,
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getHibernateTemplate().execute(new HibernateCallback(){ m),3J4(q
publicObject doInHibernate `qjiC>9
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(Session session)throws HibernateException { dh~+0FZ{A
Criteria criteria = <R6$ kom`
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detachedCriteria.getExecutableCriteria(session); %Q}T9%Mtj
return {hr+ENgV
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criteria.setProjection(Projections.rowCount .[Z<r>
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()).uniqueResult(); o771q}?&`
} \9*,[mvC
}, true); @y (9LSs
return count.intValue(); >l\?K8jL9
} >lo,0oG
} \&&jzU2
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用户在web层构造查询条件detachedCriteria,和可选的 f$lf(brQ:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;xnJ+$//U
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PaginationSupport的实例ps。 L{hP&8$k
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ps.getItems()得到已分页好的结果集 6$}hb|j
ps.getIndexes()得到分页索引的数组 *Ge2P3
ps.getTotalCount()得到总结果数 @
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ps.getStartIndex()当前分页索引 %|l^oC+E
ps.getNextIndex()下一页索引 -?A,N,nnX
ps.getPreviousIndex()上一页索引 UIUCj8QJg
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 SBBDlr^P
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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 IK%fX/tDyc
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一下代码重构了。 QRs!B!Fn0
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我把原本我的做法也提供出来供大家讨论吧: uTNmt]
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首先,为了实现分页查询,我封装了一个Page类: gDP\u<2!
java代码: Zh?1+Sz&
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/*Created on 2005-4-14*/ Sri,sZv
package org.flyware.util.page; A^PCI*SN[
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/** zG_e=
* @author Joa ,LjB%f[
* l4oI5)w
*/ J1I"H<}-6
publicclass Page { |Uz?i7z
g{&a|NU^
/** imply if the page has previous page */ ,nqG*
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privateboolean hasPrePage; &j}\ZD
VmLV:"P}^
/** imply if the page has next page */ JO:40V?op
privateboolean hasNextPage; Q ^%+r"h
krkRP%jy
/** the number of every page */ _ukKzY
privateint everyPage; sy+o{] N
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/** the total page number */ z= pb<Y@X
privateint totalPage; ' bio:1
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/** the number of current page */ 4ed+'-"m
privateint currentPage; eR.ucTji
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/** the begin index of the records by the current K8y/U(@|D
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query */ S_cba(0-|\
privateint beginIndex; 4C2J yP3
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/** The default constructor */ S/CT;M@W
public Page(){ B@ZedXi
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} {.tUn`j6V
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/** construct the page by everyPage L 0kK' n?
* @param everyPage `INcZr"
* */ Hw8`/'M=%5
public Page(int everyPage){ Wd'wL"6De
this.everyPage = everyPage; -fu=RR
} 2`,{IHu*!
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/** The whole constructor */ P`wp`HI
public Page(boolean hasPrePage, boolean hasNextPage, /C29^ P
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int everyPage, int totalPage, RO,
int currentPage, int beginIndex){ UX=JWb_uGm
this.hasPrePage = hasPrePage; ;3NA,JA#Y
this.hasNextPage = hasNextPage; N ?0T3-/K
this.everyPage = everyPage; M
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this.totalPage = totalPage; DWDL|4
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this.currentPage = currentPage; .Rxz;-VA
this.beginIndex = beginIndex; <N^2|*3
} 31-%IkX+k
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/** :WejY`}H%
* @return ='<0z?Af
* Returns the beginIndex. *,!6#Z7
*/ gl-O"%rMcL
publicint getBeginIndex(){ jLc4D'
return beginIndex; 8E1swH5z
} U}(*}Ut
nE)?P*$3 Z
/** tn201TDZ]=
* @param beginIndex :a(er'A
* The beginIndex to set. Yd:8iJA
*/ 4)ez0[i$X
publicvoid setBeginIndex(int beginIndex){ * 3mF.^
this.beginIndex = beginIndex; 62Yi1<kV@
} rWEJCFa
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/** Kf
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* @return LDHuf<`
* Returns the currentPage. n%? bMDS
*/ -4{sr|
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publicint getCurrentPage(){ ZFh2v]|!
return currentPage; S1NM9xHJ
} lpLjfHr
'+^HeM^;
/** ,
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* @param currentPage OF'y]W&
* The currentPage to set. (gZKR2hO
*/ w N9I )hB
publicvoid setCurrentPage(int currentPage){ V9f$zjpw
this.currentPage = currentPage; Va>~7
} u{maE ,
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/** ]Sg4>tp
* @return EOWLGleD1
* Returns the everyPage. ZG>I[V'p=
*/ 8V@ /h6-e,
publicint getEveryPage(){ -bT1Qh
X
return everyPage; < I[ Vv'x
} 0@[]l{N
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/** y}dop1zp
* @param everyPage \?A 7{IY
* The everyPage to set. aaW(S K
*/ Ub!MyXd{q
publicvoid setEveryPage(int everyPage){ EEmYfP[3
this.everyPage = everyPage; CL oc
} f]N2(eM
)OxcJPo
/** uc4#giCD
* @return v {E~R
* Returns the hasNextPage. ;2-%IA,
*/ R@Ch3l@
publicboolean getHasNextPage(){ 7xidBVx
return hasNextPage; ^6tGj+D9
} ew8f7S[
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/** `) s]T.-
* @param hasNextPage jt5en;AA[
* The hasNextPage to set. ,tBb$T)7<
*/ K1]m:Y<
publicvoid setHasNextPage(boolean hasNextPage){ HC4qP9Gs
this.hasNextPage = hasNextPage; i|A0G%m] $
} V4kt&61
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/** jt9fcw
* @return HAJK%zLc
* Returns the hasPrePage. 5{?J5
*/ .
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publicboolean getHasPrePage(){ X}Heaqn
return hasPrePage; HX\^ecZ#E
} i!5zHn
3Q'Q %2
/** ^i>Tm9vM
* @param hasPrePage q5<'pi
* The hasPrePage to set. ?86q8E3;&
*/ }U-h^x'
publicvoid setHasPrePage(boolean hasPrePage){ tB-0wD=PR
this.hasPrePage = hasPrePage; @,btQ_'X
} M:&g5y&
:5`=9_|
/** a'3|EWS
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* @return Returns the totalPage. Yn!)('FdT!
* 90ZMO7_
*/ ,ru2C_LQ
publicint getTotalPage(){ _`'VOY`o
return totalPage; wB%:RI,
} PL*Mz(&bf
3.[ fTrzJ
/** |ipL.<v7
* @param totalPage !$}:4}56F
* The totalPage to set. ']]Czze
*/ 1<
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publicvoid setTotalPage(int totalPage){ 0^?:Zds
this.totalPage = totalPage; 8n_!WDD
} > J4Tk1//b
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} ~<
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 J3
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个PageUtil,负责对Page对象进行构造: Xaz`L
java代码: "$@>n(w
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/*Created on 2005-4-14*/ j.}@ 9
package org.flyware.util.page; 0#$<2
3
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import org.apache.commons.logging.Log; b-'T>1V
import org.apache.commons.logging.LogFactory; cJp:0'd
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/** pv
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* @author Joa E[IjeJB5
* )uG7 DR
*/ H YA<
publicclass PageUtil { U;PGBoe
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privatestaticfinal Log logger = LogFactory.getLog Oq[2<ept
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(PageUtil.class); Nj p?/r
"xr=:[n[
/** '3<AzR2
* Use the origin page to create a new page F=T};b
* @param page D]P_tJI
* @param totalRecords %1\MW+
* @return QGC%, F"+
*/ S)n+E\c
publicstatic Page createPage(Page page, int =qg;K'M5
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totalRecords){ 1o
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return createPage(page.getEveryPage(), c3L)!]kB
%I`%N2ss
page.getCurrentPage(), totalRecords); sYMgi D
} qD]&&"B
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/** zyHHz\{
* the basic page utils not including exception p-qt?A
!0}SZ
handler 5LYzX+a)
* @param everyPage "t
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* @param currentPage ,NA _pvH)
* @param totalRecords u#Z#NP ~F0
* @return page 9 SBVp6'
*/ UN8]>#\"`
publicstatic Page createPage(int everyPage, int t[|aM-F&>
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currentPage, int totalRecords){ >Q-"-X1
everyPage = getEveryPage(everyPage); u]<_6;_
currentPage = getCurrentPage(currentPage); A0A]#=S
int beginIndex = getBeginIndex(everyPage, ~LG<Uu
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currentPage); mne?r3d
int totalPage = getTotalPage(everyPage, dEvjB"x
NB.s2I7
totalRecords); a3wk#mH
boolean hasNextPage = hasNextPage(currentPage, x^959QO~
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totalPage); YqEB%Y~N+
boolean hasPrePage = hasPrePage(currentPage); Mr}K-C?ge
F, 39'<N[
returnnew Page(hasPrePage, hasNextPage, "<Q,|Md
everyPage, totalPage, vIQu"J&fE
currentPage, Ia%S=xU{=
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beginIndex); {kdS t1
} fgW>~m.W
1:j[p=Q&
privatestaticint getEveryPage(int everyPage){ +>BD^[^^
return everyPage == 0 ? 10 : everyPage; 5<RZht$i
} cxB{EH,2Um
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privatestaticint getCurrentPage(int currentPage){ :H8`z8=0f{
return currentPage == 0 ? 1 : currentPage; vdFP ^06
} wticA#mb
p
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privatestaticint getBeginIndex(int everyPage, int T:|PSJc0
g?1! /+
currentPage){ RbN# dI'
return(currentPage - 1) * everyPage; *,y .%`o
} ^ - H
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privatestaticint getTotalPage(int everyPage, int d#Xt2
tGVC"a
totalRecords){ 3j}@}2D
int totalPage = 0; _I<LB0kgf.
qP4vH]
if(totalRecords % everyPage == 0) %VsIg
totalPage = totalRecords / everyPage; 0~GtK8^B
else IM 8lA
totalPage = totalRecords / everyPage + 1 ; Re]7G.y
FJH'!P\
return totalPage; rL3 f%L
} 7]pi .1i
cwC-)#R']
privatestaticboolean hasPrePage(int currentPage){ SMIr@*R
return currentPage == 1 ? false : true; 3{ FUFx
} )2dTgvy
uNXKUJ V0
privatestaticboolean hasNextPage(int currentPage, q-5U,!!W/
=ec"G2$?"
int totalPage){ 6ntduXeNVh
return currentPage == totalPage || totalPage == m0[JiwPI
IWs)n1D*]
0 ? false : true; 4O1[D?)`x
} (I0QwB
y{O817 \
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} T/Fj0'
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j _p|>f<}
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 *wNO3tP't
S*9qpes-m|
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 KXvBJA$
PH6NU&H
做法如下: /KLs+^c5
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 45H(.}&f
w$j!89@)
的信息,和一个结果集List: DVLF8]5
java代码: 3V)NM%Aw
l?J|Ip2W
b@?pofZ`k
/*Created on 2005-6-13*/ KDEcR
package com.adt.bo; N}5'Hk4+
`S+B-I0
import java.util.List; pon0!\ZT=
JVawWw0q
import org.flyware.util.page.Page; 4 /Q4sE~<
29~Bu5
/** rUOl+p_47
* @author Joa W &HF*Aw
*/ jt,dr3|/n
publicclass Result { LktH*ePO
;[R#:Rk
private Page page; 7,:$, bL
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private List content; lOJ3_8
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/** Ir\f_>7
* The default constructor 4ht+u
*/ #Rx|oSc}
public Result(){ JK_(!
super(); GRq0nhJ
} ?X5Y8n]y\h
_oBJ'8R\
/** d@aPhzLu
* The constructor using fields C]'ru
* p81Vt
* @param page `Eq~W@';Q0
* @param content Kg>ehn4S@
*/ =/zb$d cz
public Result(Page page, List content){ wM
aqR"%
this.page = page; G>>TB{}
this.content = content; zvAUF8'_
} r>Rm=eKJ
G>f2E49BXt
/** C0v1x=(xiM
* @return Returns the content. }{#ty uzAo
*/ +2?=W1`
publicList getContent(){ JT(6Uf
return content; Z?"f#
} `j)S7KN
/t"FZ#
/** U?.cbB,
* @return Returns the page. yNU.<d 5
*/ 3I):W9$Qp
public Page getPage(){ PT/TQW
return page; yDe6f(D
} 8DLj?M>N
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/**
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* @param content mJN*DP{
* The content to set. NcMohpkq
*/ ;:DDz
public void setContent(List content){ J,SP1-L
this.content = content; ;%W]b
} IMcuoQ5
'^10sf`"
/** qr<RMs
* @param page ]/ffA|"U`
* The page to set. 9S_PZH
*/ 1XXuFa&
publicvoid setPage(Page page){ T0TgV
this.page = page; 7H!/et?S,
} l.nd Wv
} w 8BSY
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z&KrG
1Xn:B_pP
^Iy'G44
2. 编写业务逻辑接口,并实现它(UserManager, scQnL'\
``:+*4e9
UserManagerImpl) 6m$lK%P{1
java代码: L'L[Vpx
j[Q9_0R~lR
KBOp}MEz
/*Created on 2005-7-15*/ D8 BmC
package com.adt.service; r7^oqEp@B
)eD9H*mq
import net.sf.hibernate.HibernateException; OaeX:r+&Q
Q&]f9j_
import org.flyware.util.page.Page; i@m@]-2
"K c/Cs2[
import com.adt.bo.Result; c4V%>A
xQ,My
/** F87/p
* @author Joa U[EZ,7n8
*/ lG5KZ[/Or
publicinterface UserManager { 5=_bK^Am
]{|
wU.
public Result listUser(Page page)throws SA?lDRF
Ggk#>O G
HibernateException; +L|x^B3
74r$)\q
} 3O*^[$vM
p""\uG'
bH.SUd)
B~B, L*kC2
Y'<wE2ZL)
java代码: />n!2'!
q|V|Jl
21O@yNpS$
/*Created on 2005-7-15*/ : T{VCw:*
package com.adt.service.impl; OS-k_l L
,FwpHs $A
import java.util.List; =QK ucLo
:{
iK 5
import net.sf.hibernate.HibernateException; ,xg-H6Xfa{
6l:uQz9
import org.flyware.util.page.Page; $*`E;}S0
import org.flyware.util.page.PageUtil; 85e*um^
aJ@lT&.
import com.adt.bo.Result; k
t'[
import com.adt.dao.UserDAO; }@"v7X $
import com.adt.exception.ObjectNotFoundException; ;d<O/y,:4
import com.adt.service.UserManager; -<L5;
*mH&Gn1
/** :}2T of2
* @author Joa P%ThW9^vnj
*/ yuC|_nL
publicclass UserManagerImpl implements UserManager { Ii#+JY0k
-/
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private UserDAO userDAO; p2U6B
w/:ibG@
/** \r9E6LLX'
* @param userDAO The userDAO to set. ~k%XW$cV
*/ na*Z0y
publicvoid setUserDAO(UserDAO userDAO){ 6q8PLyIp
this.userDAO = userDAO; M)U)Sc zHO
} u1gD*4+
AQ0zsy
/* (non-Javadoc) OsW*@v(
* @see com.adt.service.UserManager#listUser I2krxLPd
ZvLI~ul(zT
(org.flyware.util.page.Page) 8)MWC:
*/ qA[cF$CIl)
public Result listUser(Page page)throws 7{l~\]6d
'MW O3
HibernateException, ObjectNotFoundException { 24
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int totalRecords = userDAO.getUserCount(); ^x$1Nf
if(totalRecords == 0) k)[c!\a[i
throw new ObjectNotFoundException acgx')!c
]omBq<ox'Y
("userNotExist"); *yY\d.6(
page = PageUtil.createPage(page, totalRecords); 52NI{"
List users = userDAO.getUserByPage(page); g7lPQ_A*
returnnew Result(page, users); cnRgzj<ek
} pe>?m ^gz[
X 4!Jj*
} |qwx3 hQ?
FUZuS!sJ
ZD7qw*3+
P!IXcPKW53
mxu !$wx
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 keG\-f
d{7)_Sbky
询,接下来编写UserDAO的代码:
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3. UserDAO 和 UserDAOImpl: i) Q
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java代码: .,U4 ATO
Rlm28
!qHB?]
/*Created on 2005-7-15*/ fU\;\
package com.adt.dao; A0,e3gb
]m7x&N2
import java.util.List; VR%*8=
+?[s"(
import org.flyware.util.page.Page; =fdW H4
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import net.sf.hibernate.HibernateException; Y"^.6
:XoR~syT
/** )O$S3ojZ
* @author Joa =P_*.SgR
*/ !4<A|$mQ
publicinterface UserDAO extends BaseDAO { Y7 K2@257
%o0 H#7'
publicList getUserByName(String name)throws 9 g- 8u+&
B@*!>R
HibernateException; ep Dp*
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publicint getUserCount()throws HibernateException; yD`pUE$
AxF$7J(
publicList getUserByPage(Page page)throws SQ]M"&\{y
84i0h$ZZo
HibernateException; Fg}t{e]3a
h|ib*%P_
} TDWD8??e
+"JWsD(C(
\OWxf[
&OEBAtc/
3H4T*&9;n
java代码: %da-/[
zy8+~\a+Y&
tK'9%yA\
/*Created on 2005-7-15*/ Z:V<