Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 T^vhhfCUr
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 b0Dco0U(
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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 ?tA%A
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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 m`}mbm^
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分页支持类: E^A S65%bL
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java代码: 0TZB}c#qT
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package com.javaeye.common.util; FbRGfHL[
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import java.util.List; \&b 9
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publicclass PaginationSupport { o(4gh1b%
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publicfinalstaticint PAGESIZE = 30; f;AI4:#I
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privateint pageSize = PAGESIZE; Jy\0y[f*
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privateList items; u /]P
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privateint totalCount; sO}CXItC+j
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privateint[] indexes = newint[0]; i&?\Pp;5-j
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privateint startIndex = 0; <p}7T]a7
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public PaginationSupport(List items, int lX.-qCV"B
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totalCount){ NGJst_
setPageSize(PAGESIZE); {*P[dyu
setTotalCount(totalCount); (Ldvx_
setItems(items);
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setStartIndex(0); HNCu:$Wr@
} bN7m[GRO.
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public PaginationSupport(List items, int n_Qua|R
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totalCount, int startIndex){ ul#y'iY]
setPageSize(PAGESIZE); ]tf`[bINP
setTotalCount(totalCount); OGIv".~s4
setItems(items); x;<0Gg~jB
setStartIndex(startIndex); NyT%S?@y<
} @HPr;m!
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public PaginationSupport(List items, int IT{c:jo1{`
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totalCount, int pageSize, int startIndex){ 0|.jIix;
setPageSize(pageSize); ^b$_I31D
setTotalCount(totalCount); oyr b.lu/
setItems(items); Q4_r) &np
setStartIndex(startIndex); o$eCd{HuX
} @&Z^WN,x
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publicList getItems(){ _ xTpW
return items; qZ'2M.;
} /#
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publicvoid setItems(List items){ Hy1$Kvub
this.items = items; AH :uG#
} e4,SR(O>
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publicint getPageSize(){ Zp^O1&\SK?
return pageSize; )obgEJ7Y`l
} H`'a|Y
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publicvoid setPageSize(int pageSize){ T.3{}230<
this.pageSize = pageSize; tsL
; wT_
} 8["%e#%`$
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publicint getTotalCount(){ ]XbMqHGS
return totalCount; &R?`QB2/
} V:'F_/&X?
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publicvoid setTotalCount(int totalCount){ LXh}U>a9
if(totalCount > 0){ A&)2m
this.totalCount = totalCount; cM3B5Lp
int count = totalCount / Q"C*j'n
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pageSize; ]95VMyN
if(totalCount % pageSize > 0) `BK b60
count++; ;cvMNU$fN
indexes = newint[count]; | bRU=dg
for(int i = 0; i < count; i++){ [K$5Rm5
indexes = pageSize * $8rnf
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} bsDA&~)s
}else{ ((+XzV>
this.totalCount = 0; r'jUB^E
} n"T ^
} tp}/>gU!
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;
publicint[] getIndexes(){ 9Y'pT.Gyb
return indexes; Q5T3
} d\nXK#)Q
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publicvoid setIndexes(int[] indexes){ QMz =e
this.indexes = indexes; c0'ryS_Z9
} V~[b`&F
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publicint getStartIndex(){ 4r7F8*z
return startIndex; e)n ,Y
} y;Cs#eo
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publicvoid setStartIndex(int startIndex){ o=_7KWOA
if(totalCount <= 0) #p@GhI!6
this.startIndex = 0; '"E!av>
elseif(startIndex >= totalCount) OQ hQ!6
this.startIndex = indexes T2S_>
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[indexes.length - 1]; cJaA*sg
elseif(startIndex < 0) k:Y\i]#yP
this.startIndex = 0; $
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else{ U%s@np
this.startIndex = indexes !(F?`([A
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[startIndex / pageSize]; KCyV |,+n
} Z8ea)_{#
} DOJydYds
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publicint getNextIndex(){ dhob]8b
int nextIndex = getStartIndex() + IZj`*M%3
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pageSize; o& FOp'
if(nextIndex >= totalCount) rL1yq|]I
return getStartIndex(); a%B&F|u
else '~&W'='b;
return nextIndex; wpM2{NTP
} 6whPW
.
} 7
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publicint getPreviousIndex(){ 4F|79U #
int previousIndex = getStartIndex() - xj;:B( i
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pageSize; {73V?#P4
if(previousIndex < 0) F1stRZ1ZI
return0; {\D&*
else KJ'ID
return previousIndex; mG\QF0h
} 'G l~P><e
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} `^SRg_rH=`
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抽象业务类 g,._3.D
java代码: !92e$GJ} ;
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/** S4_/%~?
* Created on 2005-7-12 [[IMf-]
*/ Pl/ dUt_
package com.javaeye.common.business; =|z:wlOs
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import java.io.Serializable; hU""YP~y
import java.util.List; *uyP+f2O
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import org.hibernate.Criteria; ]qT&6:;-]
import org.hibernate.HibernateException; U<w8jVE
import org.hibernate.Session; H KrENk
import org.hibernate.criterion.DetachedCriteria; s;9Du|0f^
import org.hibernate.criterion.Projections; =4eJ@EVM
import 7yfh4-1M
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F
org.springframework.orm.hibernate3.HibernateCallback; Jx.fDVJ
import am]M2+,2Ip
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org.springframework.orm.hibernate3.support.HibernateDaoS nU>P%|loXx
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upport; eZPeyYX
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import com.javaeye.common.util.PaginationSupport; V+"%BrM
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public abstract class AbstractManager extends p3U)J&]c6
^ f! M"@
HibernateDaoSupport { 9-c3@>v
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privateboolean cacheQueries = false; .Z[4:TS
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privateString queryCacheRegion; +<1 |apS1
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publicvoid setCacheQueries(boolean e%JIqKS
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cacheQueries){ skcyLIb
this.cacheQueries = cacheQueries; 58s-RO6
} M4C8K{}
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publicvoid setQueryCacheRegion(String +-<G(^
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queryCacheRegion){ e3;&
this.queryCacheRegion = %v8&
}#ZRi}f2VJ
queryCacheRegion; ]#]Z]9w
} &|k=mxox\
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publicvoid save(finalObject entity){ >)ekb7
getHibernateTemplate().save(entity); V6][*.i!9
} [;z\bV<S
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publicvoid persist(finalObject entity){ Qfm$q~`D^W
getHibernateTemplate().save(entity); ^Lgvey%
} w{W+WJ
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publicvoid update(finalObject entity){ Czjb.c:a.Y
getHibernateTemplate().update(entity); L\2"1%8Wj
} ^w^e~0
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publicvoid delete(finalObject entity){ @Ul3J )=m
getHibernateTemplate().delete(entity); -O *_+8f
} 6j|Ncv
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publicObject load(finalClass entity,
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finalSerializable id){ ST?{H SCz
return getHibernateTemplate().load E#KZZ lbx
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(entity, id); 5b}w
} S&!(h
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publicObject get(finalClass entity, ?kO.>o
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finalSerializable id){ +LRKS
return getHibernateTemplate().get 0/)2RmF
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(entity, id); dC({B3#e{
} qf x*a88
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publicList findAll(finalClass entity){ PGP#$JC
return getHibernateTemplate().find("from O6G\0o
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" + entity.getName()); ~!Nj DDk
} fmuh9Z
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publicList findByNamedQuery(finalString 6'^E
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namedQuery){ n*7^lAa2
return getHibernateTemplate +c~&o83[
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().findByNamedQuery(namedQuery); x:FZEyalG
} 9w=7A>.U
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publicList findByNamedQuery(finalString query, 2GptK"MrD
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finalObject parameter){ >Q /;0>V
return getHibernateTemplate 1#=9DD$4
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().findByNamedQuery(query, parameter); /i,n75/y?
} X}Oe 'y
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publicList findByNamedQuery(finalString query, H'k}/<%Q
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finalObject[] parameters){ VCWW(Y1Fd
return getHibernateTemplate I<#X#_YP
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().findByNamedQuery(query, parameters); 712nD ?>
} G`FYEmD
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publicList find(finalString query){ BY~Tc5
return getHibernateTemplate().find vIRT$W' O}
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(query); qofAA!3z
} Z5vdH5?!r
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publicList find(finalString query, finalObject -0^]:
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parameter){ t+U.4mS-
return getHibernateTemplate().find KZ%i&w#<
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(query, parameter); T01Iu
} OIPY,cj~
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public PaginationSupport findPageByCriteria FoetP`
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(final DetachedCriteria detachedCriteria){ MDlH[PJ@i
return findPageByCriteria M.Yp'Av
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); zr|DC] 3
} I>;{BYPV
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public PaginationSupport findPageByCriteria 3=d%WPgQ
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(final DetachedCriteria detachedCriteria, finalint !mxH/{+|n
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startIndex){ hWy@?r.
return findPageByCriteria +cH>'OXoB
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(detachedCriteria, PaginationSupport.PAGESIZE, <L]Gk]k_R
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startIndex); TaRPMKk
} VW\S>=O99
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public PaginationSupport findPageByCriteria bA)nWWSg=
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(final DetachedCriteria detachedCriteria, finalint e{E\YEc
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pageSize, 86=W}eV1r
finalint startIndex){ f8;?WSGyD2
return(PaginationSupport) }<^mUG
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getHibernateTemplate().execute(new HibernateCallback(){ tu}!:5xi
publicObject doInHibernate #^L&H
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(Session session)throws HibernateException { k;^$Pd?t
Criteria criteria = Uoe{,4T
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detachedCriteria.getExecutableCriteria(session); _{jC?rzb
int totalCount = Q$U5[TZm
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((Integer) criteria.setProjection(Projections.rowCount \ivxi<SR
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()).uniqueResult()).intValue(); v Z9OJrF
criteria.setProjection +;~N; BT
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}
(null); (vG*)a
List items = Dz0D ^(;V
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criteria.setFirstResult(startIndex).setMaxResults 5!?5S$>
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(pageSize).list(); "B{3q`(
PaginationSupport ps = Onq^|r's&
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new PaginationSupport(items, totalCount, pageSize, DO(};R%=
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startIndex); A;L
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return ps; tY;<S}[@7w
} 0I.KHIBk
}, true); %j\&}>P4$
} t)&U'^
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public List findAllByCriteria(final o4" [{LyT
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DetachedCriteria detachedCriteria){ <mFDC?j
return(List) getHibernateTemplate m+!.H\
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().execute(new HibernateCallback(){ DT`HS/~fH
publicObject doInHibernate ;}SGJ7
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(Session session)throws HibernateException { q? ">
Criteria criteria = q5_zsUR=
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detachedCriteria.getExecutableCriteria(session); Es+I]o0K
return criteria.list(); qj;i03 +@
} =_`q;Tu=
}, true); X\m\yv}}
} /F;2wT;
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public int getCountByCriteria(final ,Wd=!if
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DetachedCriteria detachedCriteria){ AAQ!8!
Integer count = (Integer) ee?
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}!_z\'u
getHibernateTemplate().execute(new HibernateCallback(){ NfClR HpVc
publicObject doInHibernate !\7M7
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(Session session)throws HibernateException { kf'(u..G
Criteria criteria = mFTuqujO
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detachedCriteria.getExecutableCriteria(session); ?xqS#^Z
return $l*?Ce:
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criteria.setProjection(Projections.rowCount HTYyX(ya
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()).uniqueResult(); 5a/A?9?,
} HDV-qYD|O~
}, true); U3N
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return count.intValue(); )pl5nu#<
} y7>3hfn~w
} >1`4]%
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用户在web层构造查询条件detachedCriteria,和可选的 (e'8>Pv
_ \4#I(
startIndex,调用业务bean的相应findByCriteria方法,返回一个 :2KHiT5
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PaginationSupport的实例ps。 le \f:
, ~
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ps.getItems()得到已分页好的结果集 O5r8Ghf)
ps.getIndexes()得到分页索引的数组 [
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ps.getTotalCount()得到总结果数
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ps.getStartIndex()当前分页索引 inU5eronuj
ps.getNextIndex()下一页索引 8e-nzc,]
ps.getPreviousIndex()上一页索引 A8.noV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 u~OlJ1V
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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:x|{%
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一下代码重构了。 j;.P
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我把原本我的做法也提供出来供大家讨论吧: |aLK_]!
26/<\{q~
首先,为了实现分页查询,我封装了一个Page类: a"-uJn
java代码: `"65 _?B i
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/*Created on 2005-4-14*/ w=XIpWl
package org.flyware.util.page; !M8_PC*a
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/** {LjzkXs
* @author Joa {Lal5E4-
* ;<0vvP|
*/ D\5+2 G
publicclass Page { 7R6B}B?/
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/** imply if the page has previous page */ R*pPUw\yn
privateboolean hasPrePage; KS8@A/f
@K!JE w\
/** imply if the page has next page */ pG"wQ
privateboolean hasNextPage; ]AA|BeL?|
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/** the number of every page */ >0@w"aKn
privateint everyPage; ;)h?P.]
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/** the total page number */ :oy2mi;
privateint totalPage; {xg=Ym)
*KNfPh#wi}
/** the number of current page */ 9~`#aQG T
privateint currentPage; xwo*kFg
bhpaC8|
/** the begin index of the records by the current iN8[^,2H|
9_wDh0b~p
query */ O^!ds
privateint beginIndex; C:No ^nH>
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/** The default constructor */ WA2NjxYz
public Page(){ [q%`q`EG
\2;!}
} N4;g"k b
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/** construct the page by everyPage O>~@>/#
* @param everyPage |aenQA#
* */ JYWoQ[ZO#>
public Page(int everyPage){ )A*53>JV
this.everyPage = everyPage; c<Cf|W
} Z e>R@rK
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/** The whole constructor */ zwC ,,U
public Page(boolean hasPrePage, boolean hasNextPage, 5{(4%
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int everyPage, int totalPage, fNi&r0/-t
int currentPage, int beginIndex){ ,ASNa^7/>
this.hasPrePage = hasPrePage; v76P?[
this.hasNextPage = hasNextPage; gw"SKp!]
this.everyPage = everyPage; IT:WiMDQ}
this.totalPage = totalPage; odca?
this.currentPage = currentPage; Ud+,/pE>FA
this.beginIndex = beginIndex; /1Gmga5
} #W8F_/!n|
oH17!$Fly
/** d:iJUVpr
* @return w/
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* Returns the beginIndex. I`oJOLV
*/ d1_kw
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publicint getBeginIndex(){ MJX4;nbl
return beginIndex; ??aO3Vm{
} A-L1vu;
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/** 9b >+ehj B
* @param beginIndex 4z P"h0
* The beginIndex to set. 3r#['UmT
*/ W*s=No3C
publicvoid setBeginIndex(int beginIndex){ P7W|e~]Yq
this.beginIndex = beginIndex; ?,7!kTRH
} cZ)JvU9]
d#+Nef5
/** \(7A7~
* @return vTFG*\Cq
* Returns the currentPage. 3.Mpd
*/ s@$0!8sxm
publicint getCurrentPage(){ D(Rr<-(
return currentPage; V+D5<nICr
} >'Lkn2WI
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/** f_PH?
* @param currentPage ;{0alhMZ
* The currentPage to set. 5cf?u3r!qJ
*/ 5\zR>Tg".
publicvoid setCurrentPage(int currentPage){ (M|DNDM'd
this.currentPage = currentPage; Q?T+^J
} zd 2_k 9
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/** *=B<S/0
* @return e.L&A|
* Returns the everyPage. 8F<|.V;
*/ .?CaU
publicint getEveryPage(){ IT= y+
return everyPage; /"="y'Wx
} % S"z9@
n;.
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/** Q3& ?28
* @param everyPage /,uxj5_cT
* The everyPage to set. _;^x^
*/ Oto8?4[n
publicvoid setEveryPage(int everyPage){ $X;OK
this.everyPage = everyPage; vh&~Y].W Y
} nLAwo3
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/** 2k=|p@V n~
* @return %pWJ2J@
* Returns the hasNextPage. }R}M>^(R4
*/ >0:3CpO*
publicboolean getHasNextPage(){ O[$X36z
return hasNextPage; ?glx8@
} N:Q.6_%^
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/** "LDNkw'
* @param hasNextPage :j3^p8]
* The hasNextPage to set. J
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*/ > .}G[C
publicvoid setHasNextPage(boolean hasNextPage){ X}
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this.hasNextPage = hasNextPage; ~0024B[G
} Q'cWqr
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/** GGwwdB\x'
* @return Yur}<>`(
* Returns the hasPrePage. D@sMCR
*/ n%\\1
publicboolean getHasPrePage(){ $#/8l58
return hasPrePage; Fv,c8f
} E$ 8-8[
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/** dk1q9Tx
* @param hasPrePage d<
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* The hasPrePage to set. .$d:c61X
*/ +KExK2=
publicvoid setHasPrePage(boolean hasPrePage){ 3,i`FqQa
this.hasPrePage = hasPrePage; Y:+:>[F
} %r6_['T
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/** fh_:ung
* @return Returns the totalPage. jX' pUO
* @|<nDd{2
*/ %vf;qVoA~
publicint getTotalPage(){ Dz.kJ_"Ro
return totalPage; s$9ow<oi]
} sX>|Y3S\U
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/** K; hP0J
* @param totalPage }Dcpe M?
* The totalPage to set. OmK0-fa/
*/ O*/Utl
publicvoid setTotalPage(int totalPage){ 2y$DTMu
this.totalPage = totalPage; uU$/4{
} ](-[
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} nx`W!|g$`
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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 Lrx"Hn{
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个PageUtil,负责对Page对象进行构造: 7~MWp4.
java代码: zhRF>Y`
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/*Created on 2005-4-14*/ T8T,G4Q
package org.flyware.util.page; _mQ~[}y+?
k
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import org.apache.commons.logging.Log; bDw\;bnG
import org.apache.commons.logging.LogFactory; b1e)w?n
:SF8t` 4`
/** R*dXbI&,e
* @author Joa Ax!@vL&@
* TxkvHiq2
*/ I[ZWOi\-
;
publicclass PageUtil { I.6#>=
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privatestaticfinal Log logger = LogFactory.getLog aQ 6T2bQ
hA~5,K0b
(PageUtil.class); aC'#H8e|j
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/** .d)H2X
* Use the origin page to create a new page wE <PXBl\b
* @param page M@.?l=1X
* @param totalRecords :e_yOT}}
* @return lQ.3_{"s
*/ |>I4(''}
publicstatic Page createPage(Page page, int kP~ ;dJD
9fSX=PVRmQ
totalRecords){ uTrGb:^
return createPage(page.getEveryPage(), rPW9lG
%%O_:@9x,
page.getCurrentPage(), totalRecords); c$hoqi |tD
} y3V47J2o
t&bE/i_T
/** .|kp`-F51
* the basic page utils not including exception =6w(9O
t9
id^
handler W9SEYkg
* @param everyPage
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* @param currentPage DGAg#jh
* @param totalRecords ORV'dr
* @return page 37,)/8]lG
*/ /z,+W9`
publicstatic Page createPage(int everyPage, int xaSiG
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currentPage, int totalRecords){ N
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everyPage = getEveryPage(everyPage); 0ipYXbC
currentPage = getCurrentPage(currentPage); <_Po/a!c3
int beginIndex = getBeginIndex(everyPage, W.b?~
U./1OZ&
currentPage); %eqL)pC]
int totalPage = getTotalPage(everyPage, z?_5fte`
.Wci@5:3
totalRecords); kObgoMT<[
boolean hasNextPage = hasNextPage(currentPage, b9Ix*!Y
5adB5)`
totalPage); 1Yv#4t
boolean hasPrePage = hasPrePage(currentPage); [SLBA_d
I03
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returnnew Page(hasPrePage, hasNextPage, [Hp"a^~r|
everyPage, totalPage, 3D7phq>.q
currentPage, F
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Uw_z9ZL
beginIndex); /`VtW$9-
} .mS'c#~5Y
#T)gKp
privatestaticint getEveryPage(int everyPage){ i_;]UvP
return everyPage == 0 ? 10 : everyPage; *8QGv6*vQ
} 8[z& g%u
9ev"BO
privatestaticint getCurrentPage(int currentPage){ d `+cNKf
return currentPage == 0 ? 1 : currentPage; MU&P+Wr
} F_Mi/pB^`9
G@n%P~
privatestaticint getBeginIndex(int everyPage, int 3UX} )mW
=G2A Ufn
currentPage){ =}AwA5G
return(currentPage - 1) * everyPage; A|U_$!cLZ
} D3%`vqu&
vo DTU]pf
privatestaticint getTotalPage(int everyPage, int 'roZ:NE
x-{awP
totalRecords){
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int totalPage = 0; lF LiW
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if(totalRecords % everyPage == 0) ,
totalPage = totalRecords / everyPage; XmoS$/#"
else %sLij*
totalPage = totalRecords / everyPage + 1 ; ]LhNP}c
A,qWg0A]nt
return totalPage; FVcooV
} 3$`qy|=zO
M e
privatestaticboolean hasPrePage(int currentPage){ V qW(S1w
return currentPage == 1 ? false : true; GzUgzj|BN~
} 3l@={Ts
0zAj.iG
privatestaticboolean hasNextPage(int currentPage, Ge;plD-f
U= PG0
int totalPage){ VFMg$qv|_
return currentPage == totalPage || totalPage == cx8H.L
WNPdy m
0 ? false : true; "8"7AoE
} ^*]0quu=z
:bgi*pR{
UI 7JMeV
} yVM
1W"Q
29#;;n}p
ewtoAru
?9801Da#/
`jb?6;15
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 |EaEdA@T
=e,2/Ep{i
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8Mq]
V
v
U:`g12
做法如下: HJ*W3Mg
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 a[GlqaQy+-
b='YCa
的信息,和一个结果集List: "+ji`{
java代码: #9Z*.
3y?ig2
pr[[)[]/
/*Created on 2005-6-13*/ T(^<sjOs
package com.adt.bo; &4yI]
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import java.util.List; <c6C+OWT,
k]"Rg2>%
import org.flyware.util.page.Page; <5~} !N X`
Ee##:I[z
/** X] /r'Tz
* @author Joa s Hu~;)
*/ 4PEJ}BW
publicclass Result { 7oDr`=q1]r
e}e\*BL
private Page page; HzT"{N9
-)aBS3
private List content; :r[`bqC;\*
*~|xj,md
/** QP?Z+P<
* The default constructor .Tdl'y:..
*/ y@G5I>v
public Result(){ ,bCPO`45
super(); mMw&{7b:
} U&/Jh^Yy
9\i,3:Qc
/** Tc`LY/%Od
* The constructor using fields w8(qiU
* _~DFZt@T
* @param page y?M99Vo4?
* @param content 'wX'}3_/g
*/ h2u>CXD
public Result(Page page, List content){ rj*4ZA?
this.page = page; !\8j[QS!
this.content = content; 8+uwzBNZ:
} \,E;b{PQo6
"@E1^
/** W]n%$a
* @return Returns the content. ewk62{
*/ H>`?S{J
publicList getContent(){ }{S W~yW
return content; Mx-,:a9}
} Vcl"qz@Fj
-[x^z5Ee`
/** _'dsEF
* @return Returns the page. ){")RrD(
*/ y8wOJZ<K
public Page getPage(){ ^Yn{Vi2.
return page; e4ajT
} @B~/0
9
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/** |9!3{3
* @param content <Dt,FWWkv'
* The content to set. s0.yPA
*/ ^ow[XEB%
public void setContent(List content){ X{ZBS^M
this.content = content; QKbX^C
} )D@1V=9,
>)U 7$<&b
/** v/Z}|dT"
* @param page NwuME/C7#
* The page to set. $d!Sl
a
*/ 7Z"mVh}
publicvoid setPage(Page page){ Lqbu]
this.page = page; W9Bl'e
} oyJ/Oe
{
} <<w $Ur
t[F tIj6
vBQ5-00YY=
2,;+)
EH] 5ZZ[Z
2. 编写业务逻辑接口,并实现它(UserManager, p H?VM&x
RWXj)H)w
UserManagerImpl) F1)Q#ThF\
java代码: ,$sq]_t
Sy'/%[+goJ
l8%x(N4
/*Created on 2005-7-15*/ iH(
K[F /
package com.adt.service; WUdKj
*6q8kQsz^1
import net.sf.hibernate.HibernateException; \y:
0+s/
.F?yt5{5No
import org.flyware.util.page.Page; Yq#I#
2RD
y^hpmTB3"
import com.adt.bo.Result; lVXgp'!#j
J~DP*}~XK
/** 7~eo^/PbS
* @author Joa -^$CGRE6A
*/ n@5pS3qZ
publicinterface UserManager { brNe13d3~"
V@84Cb
public Result listUser(Page page)throws usR19 _E-
JXGIVH?Rpu
HibernateException; av gGz8
V_~}7~
I
} bUAjt>+
"(/|[7D)
l?a(=
,<|EoravH
u|WX?@\
java代码: &EmxSYL>
]NuY{T&:
FI*.2rdSR
/*Created on 2005-7-15*/ g84~d(\?
package com.adt.service.impl; o]MQ)\r
S]9:3~
import java.util.List; phbdV8$L
t_3)}
import net.sf.hibernate.HibernateException; 8S@ ~^D
@+Berb
import org.flyware.util.page.Page; Otn,(j;u
import org.flyware.util.page.PageUtil; k^]+I%?Q
Fmt5"3B
import com.adt.bo.Result; _xAdvr' W
import com.adt.dao.UserDAO; @p|[7'
import com.adt.exception.ObjectNotFoundException; l8GziM{lp
import com.adt.service.UserManager; \?GUGs
`\q4z-<-
/** j"_V+)SD
* @author Joa p."pI Bd
*/ Zj~tUCc
publicclass UserManagerImpl implements UserManager { T
{(6*^g<B
w^p
'D{{
private UserDAO userDAO; 0d`s(b54;O
"KW\:uc /
/** =NF},j"
* @param userDAO The userDAO to set. 05DK-Wh?
*/ >Bskw2
publicvoid setUserDAO(UserDAO userDAO){ '8i
np[_
this.userDAO = userDAO; \0(QO8.
} mV`Z]-$$i
# u^F B
/* (non-Javadoc) *ta|,
* @see com.adt.service.UserManager#listUser sTeL4g|%{
cm-cwPAh
(org.flyware.util.page.Page) Si6%6rAhj
*/ -Qiay/tlu
public Result listUser(Page page)throws kd|@.
~Rk6@&ZS}
HibernateException, ObjectNotFoundException {
HHWB_QaL
int totalRecords = userDAO.getUserCount(); ;'}1
if(totalRecords == 0) 3UD_2[aqN(
throw new ObjectNotFoundException e0j*e7$
k-Jj k3
("userNotExist"); <|hvH
page = PageUtil.createPage(page, totalRecords); BA A)IQF
List users = userDAO.getUserByPage(page); }n:'@}
returnnew Result(page, users); UG&/0{j5XV
} G}BO!Z6
Tp)-L0kD_k
}
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2ztP'
bzk@6jR1
1xL2f&bG
RQ9fA1YP
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 JT[|l-\zo
%Ni)^
询,接下来编写UserDAO的代码: i?qS8h{
3. UserDAO 和 UserDAOImpl: 9d#-;qV
java代码: 2P!Pbl<
f/*Xw {s#
_D$|lk-
/*Created on 2005-7-15*/ Ga.a"\F.V
package com.adt.dao; 9N5&N3
!j%v Ue;t
import java.util.List; @,i:fY
MHI0>QsI
import org.flyware.util.page.Page; mAk)9`f/
>e=tem~/
import net.sf.hibernate.HibernateException; 6Nj\N oS
iKLN !QR
/** UXDd8OJL
* @author Joa (t>BO`,
*/ jNaK]
publicinterface UserDAO extends BaseDAO { rVt6tx
db@i*Bf
publicList getUserByName(String name)throws 8nt:peJ$+
#)GL%{Oa
HibernateException; -+Kx^V#'R
8"N<g'Yl,
publicint getUserCount()throws HibernateException; TW{.qed8^
CbS- Rz:
publicList getUserByPage(Page page)throws D;.-e
[Sg1\UTl
HibernateException; i0v;mc
X4Q?]{
} ] 8+!
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HP:ee+n
1bYc^(z0
]
RN&s
java代码: iNe;h|
^0pd- n@pn
VI74{='=
/*Created on 2005-7-15*/ aVNRhnM
package com.adt.dao.impl; *q=pv8&*s
|k^'}n
import java.util.List; $!G7u<`na
J LT10c3
import org.flyware.util.page.Page; r.lH@}i%n
p3&/F=T;)
import net.sf.hibernate.HibernateException; 58DkVQ 6
import net.sf.hibernate.Query; Zz!XH8sH
}JeGjpAcV
import com.adt.dao.UserDAO; ]e$mTRi*
M/EEoK^K@
/** )iNMjg
* @author Joa 9s>q4_D
*/ WldlN?[j
public class UserDAOImpl extends BaseDAOHibernateImpl }rj.N98
B:\\aOEj
implements UserDAO { =3]}87
"_eHK#)
/* (non-Javadoc) E/v.+m
* @see com.adt.dao.UserDAO#getUserByName <4ccT l
` .|JTm[
(java.lang.String) "9'~6b
*/
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publicList getUserByName(String name)throws
0w>V![
NoTEbFrV
HibernateException { Se.\wkl#Y
String querySentence = "FROM user in class #k&"Rv;,
VCSHq&p8
com.adt.po.User WHERE user.name=:name"; =
NHuj.
Query query = getSession().createQuery 5%BexIk
[fx1H~T<
(querySentence); }TY}sr
query.setParameter("name", name); b#`XmB
return query.list(); VkTdpeBV
} *1"xvle
ZJ}9g(X..g
/* (non-Javadoc) S96H`kedZo
* @see com.adt.dao.UserDAO#getUserCount() mFfw*,M
*/ N[~{'i
publicint getUserCount()throws HibernateException { Xb?:dlu3
int count = 0; tS!FnQg4
String querySentence = "SELECT count(*) FROM Veo*-sl
_0N=~`'
user in class com.adt.po.User"; 0zQ"5e?qy
Query query = getSession().createQuery -sO[,
sU! h^N$
(querySentence); 7#d>a=$h
count = ((Integer)query.iterate().next cyrVz4_a
me:~q#k
()).intValue(); Q&+Jeji
return count; F*m^AFjs
} QK% Nt
5$f
vI#NO<
/* (non-Javadoc) ,I6jfXI4
* @see com.adt.dao.UserDAO#getUserByPage -FQ!
)[fjZG[
(org.flyware.util.page.Page) 'NJGez'b,
*/ j5Kw0Wy7
publicList getUserByPage(Page page)throws ZByxC*Cz
Geyy!sr``
HibernateException { g_X-.3=2K
String querySentence = "FROM user in class [.J&@96,b
wpgO09
com.adt.po.User"; 1(%9)).K
Query query = getSession().createQuery p]h;M
i7$4i|
(querySentence); 9{[I|
query.setFirstResult(page.getBeginIndex()) TL&