Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K/Y"oQ2
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 o-&0_Zq_
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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 r7V !M1
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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 GSSmlJ`
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分页支持类: &+k*+
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java代码: ^+d]'$
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package com.javaeye.common.util; LDU4 D
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import java.util.List; hg<[@Q%$o
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publicclass PaginationSupport { iyR"O1]
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publicfinalstaticint PAGESIZE = 30; pQc-}o"
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privateint pageSize = PAGESIZE; JJg;X :p
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privateList items; 6!itr"
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privateint totalCount; Ja&S_'P[
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privateint[] indexes = newint[0]; GB}=
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privateint startIndex = 0; sz/^Ie-~
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public PaginationSupport(List items, int (`#z@,1
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totalCount){ 9(!AKKrr;
setPageSize(PAGESIZE); ^[bFG KE
setTotalCount(totalCount); -O1$jBQS
setItems(items); ]n"RPktx
setStartIndex(0); [742s]j
} Nr*X1lJ6
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public PaginationSupport(List items, int 2v@B7r4}
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0
totalCount, int startIndex){ =w`uZ;l$Q
setPageSize(PAGESIZE); w 2U302TZ
setTotalCount(totalCount); Gl|n }wo$
setItems(items); B6Ajcfy
setStartIndex(startIndex); #l- 0$
} q o^mp
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public PaginationSupport(List items, int a%kvC#B
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totalCount, int pageSize, int startIndex){ Np$&8v+en
setPageSize(pageSize); o-l-Z|)7
setTotalCount(totalCount); FZ]+(Q"]:
setItems(items); H =~7g3
setStartIndex(startIndex); ,=G]tnsv^
} 88S:E7
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publicList getItems(){ )'RaMo` 4
return items; y4I Qa.F
} j6k"%QHf
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publicvoid setItems(List items){ 7hPwa3D^
this.items = items; UA~ 4O Q]
} aMHC+R1X
eYlI };
publicint getPageSize(){ +zLw%WD[l
return pageSize; lEHXh2
} 9v-Y*\!w.
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publicvoid setPageSize(int pageSize){ kkb+qo
this.pageSize = pageSize; J}8p}8eF,
} W|zPV`
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publicint getTotalCount(){ r1vS~
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return totalCount; |nLq4.
} Rmn{Vui9\
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publicvoid setTotalCount(int totalCount){ o37oR v]
if(totalCount > 0){ |7A}LA
this.totalCount = totalCount; {=Jo!t;f
int count = totalCount / 4<E <sD
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pageSize; ewdTsgt'
if(totalCount % pageSize > 0) L%\Wt1\[
count++; iOb7g@=
indexes = newint[count]; m2l9([u=^
for(int i = 0; i < count; i++){ )wD/<7;
indexes = pageSize * _
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} Kj3Gm>B<y
}else{ Ac|dmu
this.totalCount = 0; oUN\tOiS+
} "sDs[Lcq
} \~Z%}$ =
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publicint[] getIndexes(){ V'Kied+
return indexes; ZPb30M0
} q^zG+FN
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publicvoid setIndexes(int[] indexes){ ]sVWQj
this.indexes = indexes; I"lzOD; eI
} 8{i}^.p
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publicint getStartIndex(){ X?< L<:.
return startIndex; Qyx~={.C~
} k_1@?&3
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publicvoid setStartIndex(int startIndex){ HOPy&Fp
if(totalCount <= 0) Nz`v+sp
this.startIndex = 0; r[;d.3jtP
elseif(startIndex >= totalCount) X;)/<:mX
this.startIndex = indexes ceCO *m~
qS!N\p~>
[indexes.length - 1]; Pz:,de~5Qm
elseif(startIndex < 0) =VZ_';b h
this.startIndex = 0; e?+-~]0
else{ tQNrDp+
this.startIndex = indexes 0}`-vOLd-
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[startIndex / pageSize]; Xa?igbgAwx
} em0Y' J
} W
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publicint getNextIndex(){ iZeq
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int nextIndex = getStartIndex() + W,CAg7:*
' F9gp!s8~
pageSize; &<uLr
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if(nextIndex >= totalCount) +YW;63"o
return getStartIndex(); iJ8Z^=>
else )mBYW}} T
return nextIndex; `G`R|B
} `W~
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publicint getPreviousIndex(){ ~ |A0*
int previousIndex = getStartIndex() - Xz)F-C27h
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pageSize; J+
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if(previousIndex < 0) rQ]JM
return0; F4z#u2~TC
else QQV8Vlv"
return previousIndex; =MJB:
} ~XuV:K3
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} M_ %-A
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抽象业务类 aHpZhR|f$
java代码: ZBY2,%nAo
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/** '=Lpch2J
* Created on 2005-7-12 *kqC^2t
*/ 'xkl|P>=],
package com.javaeye.common.business; /P TRe5-7
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import java.io.Serializable; sHk>ek]2I
import java.util.List; P3|s}&
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import org.hibernate.Criteria; a <?~1pWtc
import org.hibernate.HibernateException; ! {G0'
import org.hibernate.Session; l}VE8-XB
import org.hibernate.criterion.DetachedCriteria; jED.0,+K!
import org.hibernate.criterion.Projections; ;e5PoLc
import +D]raU
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org.springframework.orm.hibernate3.HibernateCallback; v7./u4S|V
import LFHJj-nk
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org.springframework.orm.hibernate3.support.HibernateDaoS Q#SQ@oUzD
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upport; !1=OaOT
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import com.javaeye.common.util.PaginationSupport; 2 Kjd!~Z$
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public abstract class AbstractManager extends breF,d$
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HibernateDaoSupport { t&{;6MiE
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privateboolean cacheQueries = false; 7(.Z8AO
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privateString queryCacheRegion; 8/dMvAB1So
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publicvoid setCacheQueries(boolean o&%v"#H2
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cacheQueries){ -#;xfJE
this.cacheQueries = cacheQueries; Z*mbhod
}
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publicvoid setQueryCacheRegion(String Hh=fv~X
|> ]@w\]
queryCacheRegion){ +c<iVc|
this.queryCacheRegion = r \ft{Z<P
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queryCacheRegion; QE[<Y3M
} .aY$-Y<
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publicvoid save(finalObject entity){ Y 2ANt w@
getHibernateTemplate().save(entity); pl&nr7\
} ur'<8pDb$
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publicvoid persist(finalObject entity){ #Iz)Mu
getHibernateTemplate().save(entity); S5 q1Mn
} lRg?||1ik
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publicvoid update(finalObject entity){ nD*iSb*
getHibernateTemplate().update(entity); t
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} z6E =%-`
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publicvoid delete(finalObject entity){ s~ 8g
getHibernateTemplate().delete(entity); 2Wluc37
} Vl5>o$G|<.
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publicObject load(finalClass entity, =+j3E<w
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finalSerializable id){ C&w0HoF
return getHibernateTemplate().load &F~d~;G"q
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(entity, id); \vT~2Y(K
} z&d.YO_W
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publicObject get(finalClass entity, xE?KJ
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finalSerializable id){ e3;D1@
return getHibernateTemplate().get \Yr*x7!
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(entity, id); B0Wf$
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} v~L\[&|_
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publicList findAll(finalClass entity){ lF}@@e)N
return getHibernateTemplate().find("from @L!^2v
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" + entity.getName()); cHF W"g78
} )>FAtE
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publicList findByNamedQuery(finalString o( zez
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namedQuery){ hTn"/|_SW
return getHibernateTemplate jerU[3
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().findByNamedQuery(namedQuery); bOr11?
} a`w=0]1&*
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publicList findByNamedQuery(finalString query, KUZi3\p9W>
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finalObject parameter){ S#C-j D
return getHibernateTemplate ;`7~Q
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().findByNamedQuery(query, parameter); *%;A85V/
} 9S]pC?N]E
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publicList findByNamedQuery(finalString query, u?72]?SM
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finalObject[] parameters){ ^R@)CIQ
return getHibernateTemplate _D4qnb@
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().findByNamedQuery(query, parameters); .2@T|WD!Ah
} 49*f=gpGj2
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publicList find(finalString query){ |(%<FY$
return getHibernateTemplate().find t^":.}[Q
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(query); i;%G Z8
} !I?C8)
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publicList find(finalString query, finalObject j13-?fQ&
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parameter){ c.]QIIdK
return getHibernateTemplate().find A2ye
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(query, parameter); H I|a88
} aYa`ex
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public PaginationSupport findPageByCriteria F!#)l*OX;
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(final DetachedCriteria detachedCriteria){ Zt9G[[]
return findPageByCriteria R5=J :o
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3'.3RKV
} R&W%E%uj
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public PaginationSupport findPageByCriteria G]aey>)
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(final DetachedCriteria detachedCriteria, finalint 9]=J+ (M
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startIndex){ o
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return findPageByCriteria ),N,!15j,
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(detachedCriteria, PaginationSupport.PAGESIZE, q#AEu
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startIndex); 4Px|:7~wT8
} a+LK~mC*
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public PaginationSupport findPageByCriteria x] wi&
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, K]$PRg1|3
finalint startIndex){ ^O7sQ7V"f=
return(PaginationSupport) kBk>1jn"
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getHibernateTemplate().execute(new HibernateCallback(){ HQ"T>xb
publicObject doInHibernate h!SsIy(
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(Session session)throws HibernateException { 2EM6k|l5
Criteria criteria = bI0xI[#Q
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detachedCriteria.getExecutableCriteria(session); Ox J0."
int totalCount = m@kLZimD
"W+>?u )
((Integer) criteria.setProjection(Projections.rowCount `$jun
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()).uniqueResult()).intValue(); hev;M)t
criteria.setProjection $rW(*#C
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(null); bh5D}w
List items = =|AYT6z,
>+7{PF+sB
criteria.setFirstResult(startIndex).setMaxResults ]
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Mu/(Xp6 2
(pageSize).list(); :u9'ZHkZ
PaginationSupport ps = DQ+6VPc^o
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new PaginationSupport(items, totalCount, pageSize, *yT>
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startIndex); W6>t!1oO+
return ps; Ci-Ze j
} FLG"c690
}, true); tcoG;ir
} '9u?lA^9$
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public List findAllByCriteria(final h9 DUS,G9,
,(q]
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DetachedCriteria detachedCriteria){ grE(8M
return(List) getHibernateTemplate 4#>Z.sf
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().execute(new HibernateCallback(){ L~/,;PHN
publicObject doInHibernate f$:Y'$Z1
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(Session session)throws HibernateException { l9uocP:D
Criteria criteria = j17h_ a;
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detachedCriteria.getExecutableCriteria(session); !{+CzUo@
return criteria.list(); Z4Q]By:/L
} O'(Us!aq
}, true); ( gg )?
} ;8PO}{rD
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public int getCountByCriteria(final ,&@GxiU
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DetachedCriteria detachedCriteria){ 4F.,Y3
Integer count = (Integer) U)f('zD
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getHibernateTemplate().execute(new HibernateCallback(){ #b*4v&<
publicObject doInHibernate jC[_uG
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(Session session)throws HibernateException { :qxWANUa
Criteria criteria = cdkEK
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detachedCriteria.getExecutableCriteria(session); yfV]f
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return V/H+9+B7Im
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criteria.setProjection(Projections.rowCount 'dBe,@
^cw9Yjh6
()).uniqueResult(); Ojz'p5d`>
} 3m75mny
}, true); vrb@::sy0T
return count.intValue(); v\|jkzR5Y
} nZnqXclzxn
} TO89;O
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用户在web层构造查询条件detachedCriteria,和可选的 #z >I =gl
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *K_8=TIA*
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PaginationSupport的实例ps。 d6*84'|!
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ps.getItems()得到已分页好的结果集 <eMqg u
ps.getIndexes()得到分页索引的数组 V-#JV@b
ps.getTotalCount()得到总结果数 >vo 6X]p~
ps.getStartIndex()当前分页索引 -){6ynqv
ps.getNextIndex()下一页索引 ,gZp/ yJ;
ps.getPreviousIndex()上一页索引 'gor*-o:wu
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]QR]#[Tn'
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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 xP~GpVhLF
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一下代码重构了。 \(
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我把原本我的做法也提供出来供大家讨论吧: ?xUl_
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首先,为了实现分页查询,我封装了一个Page类: U[3w9
java代码: =(hBgNH
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/*Created on 2005-4-14*/ :Ef!gpS}?R
package org.flyware.util.page; zqt<[=O
sE&nEc
/** #2i$:c~
* @author Joa iJhieNn
* e eN`T&cI
*/ kSEA
publicclass Page { N KgEs
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/** imply if the page has previous page */ e@VJ-s
privateboolean hasPrePage; X=-= z5
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/** imply if the page has next page */ XdDQ$'*X
privateboolean hasNextPage; <%3fJt-Ie
\?v&JmEU
/** the number of every page */ <2@t~9
privateint everyPage; MF.!D;s
IWi0? V
/** the total page number */ P=EZ6<c3&
privateint totalPage; Gi-pi=#&cs
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/** the number of current page */ < w}i
privateint currentPage; lwt,w<E$
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/** the begin index of the records by the current G3|23G.~)(
En7+fQ
query */ 0^Ldw)C"
privateint beginIndex; **__&Xp1
bj0HAgY@
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/** The default constructor */ ;DX{+Z[
public Page(){ Q(N'Oj:J
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} "24d:vf\
6[XaIco=C
/** construct the page by everyPage {BM:c$3@j
* @param everyPage VB |k
* */ Mz$qe
public Page(int everyPage){ b/\O;o}]
this.everyPage = everyPage; Z(RsB_u5
} )x[=}0C
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/** The whole constructor */ |mG;?>c)
public Page(boolean hasPrePage, boolean hasNextPage, 1f^oW[w&
,[p?u']yZz
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int everyPage, int totalPage, yg}L,JJU<
int currentPage, int beginIndex){ +e>G V61
this.hasPrePage = hasPrePage; >h2qam
this.hasNextPage = hasNextPage; "K>!+<
this.everyPage = everyPage; 9{nU\am!\
this.totalPage = totalPage; _6.@^\;
this.currentPage = currentPage; Bz,D4E$
this.beginIndex = beginIndex; p=[dt
} 7Y~5gn
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/** 7>7n|N
* @return g- #eMQ%J
* Returns the beginIndex. QP<P,Bi~
*/ moVf(7
publicint getBeginIndex(){ #|769=1
return beginIndex; ;w%g*S
} q{*[uJ}Xc"
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/** r{yIF~k@
* @param beginIndex "o;%em*Bc
* The beginIndex to set. J.2BBy
*/ Yy[=E\z
publicvoid setBeginIndex(int beginIndex){ ^+~$eg&js
this.beginIndex = beginIndex; uq:'`o-1
} uJ=&++[
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/** jc6~V$3
* @return nC/T$
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* Returns the currentPage. \K9Y@jnr
*/ coaJDg+
publicint getCurrentPage(){ '%Oo1:wJ
return currentPage; $?: -A
} RToX[R;1E
0=`aXb-
/** H!y@.W{_
* @param currentPage @AG=Eq9<o
* The currentPage to set. yF` (GU
*/ P'_ aNU
publicvoid setCurrentPage(int currentPage){ ?b^<Tny
this.currentPage = currentPage;
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} )CL/%I,^
3 5-FD{
/** cP/( h
* @return ZMyd+C_P2
* Returns the everyPage. c:z}$DK&'
*/ Y=pRenV'
publicint getEveryPage(){ qy\SOAh
return everyPage; Tig6<t+Q
} ,,9vk \
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/** QIN# \
* @param everyPage Grd9yLF
* The everyPage to set. 8v;T_VN
*/ n!b*GXb\
publicvoid setEveryPage(int everyPage){ $[=`*m
this.everyPage = everyPage; ?K}KSJ6_
} R<h0RKiM@
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/** I$i1o#H
* @return *OE>gg&?Nh
* Returns the hasNextPage. a~tBg y+9
*/ E\}Q9,Z$
publicboolean getHasNextPage(){ kr1^`>O5
return hasNextPage; 5o(=?dXm4
} p|*b] 36
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/** hU2N{Ac
* @param hasNextPage tK <)A)
* The hasNextPage to set. @D<Q'7mLh
*/ ~b4fk^u`+
publicvoid setHasNextPage(boolean hasNextPage){ x2f_>tu2
this.hasNextPage = hasNextPage; FUPJ&7+B
} T5U(B3j_
H
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/** }% |GV
* @return {24Pv#ZG#^
* Returns the hasPrePage. 'Uo:b<
*/ P#Ikj&l
publicboolean getHasPrePage(){ s3T 6"%S`
return hasPrePage; \@n/L{}(@
} e''Wm.>g(+
' :]w
/** w@f_TG"Vt
* @param hasPrePage zjJyc?
* The hasPrePage to set. WUi7~Ei}
*/ %}&9[#
publicvoid setHasPrePage(boolean hasPrePage){ z<P#djx
this.hasPrePage = hasPrePage; xhMdn3~U
} 2I39fZa
?Z7C0u#wd
/** 8c$IsvJg
* @return Returns the totalPage. 54LCoG/
* 9zd)[4%=
*/ (C QgT3V
publicint getTotalPage(){ J.`.lQ$z
return totalPage; 55N/[{[
} a. 5`Q2
~JT{!wcE}o
/** !*#=7^#
* @param totalPage ;6)|'3.B9
* The totalPage to set. CnA*o 8w
*/ zKWi9
publicvoid setTotalPage(int totalPage){ XJOo.Y
this.totalPage = totalPage; anV)$PT=
} /ci.IT$Q^
g-(xuR^*
} !p9F'7;Y<
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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 s^v,i
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"|&*MjwN6
个PageUtil,负责对Page对象进行构造: p0YTZS ]h
java代码: ,>jm|BTD {
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/*Created on 2005-4-14*/ cE]kI,Fw,M
package org.flyware.util.page; FRF}V@~
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import org.apache.commons.logging.Log; `") I[h
import org.apache.commons.logging.LogFactory; 6<~y!\4;F
,zyrBO0 Eq
/** _bz,G"w+:
* @author Joa bo"I:)n;
* Tp6ysjao
*/ },L[bDOV07
publicclass PageUtil { f!Ie
r#~6FpFVK^
privatestaticfinal Log logger = LogFactory.getLog G`W+m*[U+M
vA{[F7
(PageUtil.class); u1kbWbHu(
hP#&]W3:
/** Mo<p+*8u:
* Use the origin page to create a new page %`\{Nxk
* @param page gR>#LM&dG
* @param totalRecords 6%xl}z]o
* @return C]XDDr
*/ ~gDtj&F
publicstatic Page createPage(Page page, int Bms?`7}N
,?f(~<Aj
totalRecords){ sR0nY8@F
return createPage(page.getEveryPage(), WL~`L!_. A
K=>/(sWiq
page.getCurrentPage(), totalRecords); U5PCj ]-Xt
} lqs_7HhvRS
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/** ;g*6NzdA
* the basic page utils not including exception (^4%Fk&I-
7> Qt O
handler 32Z4&~I
* @param everyPage dA~6{*)
* @param currentPage h 2zCX
* @param totalRecords y%y#Pb|
* @return page q.t5L=l^
r
*/ mB~&nDU
publicstatic Page createPage(int everyPage, int PrcM'Q
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currentPage, int totalRecords){ {Q"<q`c
everyPage = getEveryPage(everyPage); tpD?-`9o
currentPage = getCurrentPage(currentPage); StVv"YY
int beginIndex = getBeginIndex(everyPage, b6(yyYdF
BkF[nL*|
currentPage); 5*r6#[S\
int totalPage = getTotalPage(everyPage, ~eP2PG
;D7jE+
totalRecords); A!~o?ej
boolean hasNextPage = hasNextPage(currentPage, ^pP
14y*go
@wPmx*SF
totalPage); zkOgL9
(_8
boolean hasPrePage = hasPrePage(currentPage); 73.b9mF
m~K]|]iqQ
returnnew Page(hasPrePage, hasNextPage, zl[JnVF\6
everyPage, totalPage, {mQJ6
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currentPage, #@fypCc
gr=`_k4~1
beginIndex); XTJ>y@
} vX\e*
v
m @%|Q;
privatestaticint getEveryPage(int everyPage){ wMoAvA_oS
return everyPage == 0 ? 10 : everyPage; @!da1jN
} +9J>'oe'D
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u
privatestaticint getCurrentPage(int currentPage){ >>r:L3 <!
return currentPage == 0 ? 1 : currentPage; *Y ZLQT
} P.:T
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privatestaticint getBeginIndex(int everyPage, int mI%/k7:sf
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currentPage){ QFYy$T+W
return(currentPage - 1) * everyPage; a6d KQ3D
} ._Xtb,p{
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privatestaticint getTotalPage(int everyPage, int :S12=sFl$
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totalRecords){ 7fqYSMHR
int totalPage = 0; rWXW}Yg
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if(totalRecords % everyPage == 0) O)R0,OPb
totalPage = totalRecords / everyPage; B .mV\W
else M}Mzm2d#`
totalPage = totalRecords / everyPage + 1 ; 4;||g@f'[
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return totalPage; JPG!cX%
} 4/?Zp4g
fna>>
privatestaticboolean hasPrePage(int currentPage){ gOM`I+CwT
return currentPage == 1 ? false : true; $ Zr,-
} ise}> A!t
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privatestaticboolean hasNextPage(int currentPage, MVdx5,t
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int totalPage){
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return currentPage == totalPage || totalPage == cG:`Zj~4
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0 ? false : true; )[*O^bPowI
} pt#[.n#f
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} xF;v 6d
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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。 a7G2C oM8
di2=P)3
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 /g''-yT7#
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做法如下: Zd ,=
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 V bOLTc
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的信息,和一个结果集List: 9AzGk=^
java代码: j:3Hm0W3
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/*Created on 2005-6-13*/ o q)"1
package com.adt.bo; V&v~kzLr+
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import java.util.List; gq3OCA!cX
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import org.flyware.util.page.Page; wtLMc
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/** e622{dfVS
* @author Joa :OaQq@V
*/ 1o 78e2B
publicclass Result { :0/o?'s
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private Page page; 4CT9-2UC
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private List content; .6o y>4
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/** $4JX#lkt
* The default constructor }tO<_f))
*/ PM!t"[@&
public Result(){ yuDd%
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super(); q.Z#7~6`3
} v=1S
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/** BrMp_M
* The constructor using fields | V,jd
* ~j#6 goKn
* @param page 8k?L{hF|nW
* @param content }AZx/[k
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*/ *[:CbFE0y
public Result(Page page, List content){ Yka&Kkw
this.page = page; kTc5KHJ7
this.content = content; F{~r7y;0
} @ ]wem
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/** {0WIDD
* @return Returns the content. s^'#"`!v=
*/ M`pTT5r
publicList getContent(){ oHd0
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return content; +gCy@_2;
} l!V| T?
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/** i}F;fWZ`
* @return Returns the page. )h_7 2
*/ ]{+M>i[
public Page getPage(){ [k7N+W8
return page; fUKdC\WL
} LY:?OGh
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/** qS}RFM5|
* @param content BBE1}V!u
* The content to set. ^^3va)1{!
*/ x][9ptrh
public void setContent(List content){ ^1yTL5#:Vw
this.content = content; <&EO=A
} 3nC#$L-
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/** pjs9b%.
* @param page c0Ro3j\p
* The page to set. q=%
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*/ &\lS
publicvoid setPage(Page page){ [piF MxZP
this.page = page; hIo S#]
} `e'o~oSu
} )F#<)Evw
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2. 编写业务逻辑接口,并实现它(UserManager, {G1aAM\Hz
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UserManagerImpl) \g:qQ*.
java代码: fy=C!N&/
p2c=;5|/Q
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/*Created on 2005-7-15*/ +;wqX]SD &
package com.adt.service; ""v`0OP&J
vWi.[]
import net.sf.hibernate.HibernateException; s.I1L?s1w?
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import org.flyware.util.page.Page; 5az
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. (*kgv@3x
import com.adt.bo.Result; H^PqYLjN
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/** {F6dSF`
* @author Joa :n>ccZeMv
*/ *[1u[H9Cv
publicinterface UserManager { +=*m! 7Mr
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public Result listUser(Page page)throws P2Qyz}!wo
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HibernateException; 0.BUfuuh
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} &c<}++'h
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java代码: 4lh
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/*Created on 2005-7-15*/ 'f?&EsIV?
package com.adt.service.impl; eFj6p<
mQ^@ \s
import java.util.List; o&XMgY~
w^'?4M!
import net.sf.hibernate.HibernateException; .xLF}{u
,7fc41O3V
import org.flyware.util.page.Page; '=Kof1
import org.flyware.util.page.PageUtil; 0nD=|W\@{
[#>$k
6F*
import com.adt.bo.Result; ZP63Alt
import com.adt.dao.UserDAO; )_c=mT
import com.adt.exception.ObjectNotFoundException; EB29vHAt~
import com.adt.service.UserManager; dp[w?AMhM9
B/sBYVU
/** [*?_
* @author Joa rxy{a
*/ |:e|~sism
publicclass UserManagerImpl implements UserManager { H?`)[#
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private UserDAO userDAO; 3?*M{Y|
s*)41\V0
/** NHFEr
* @param userDAO The userDAO to set. Bd[L6J)
*/ a:-)+sgHw
publicvoid setUserDAO(UserDAO userDAO){ aZawBU.:
this.userDAO = userDAO; yA?ENAM
} e\A(#l@g
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/* (non-Javadoc) GIRSoRVsh
* @see com.adt.service.UserManager#listUser /J[H5uA
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(org.flyware.util.page.Page) iO9nvM<
*/ KYkS6|A
public Result listUser(Page page)throws L*UV
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HibernateException, ObjectNotFoundException { :zj9%4A
int totalRecords = userDAO.getUserCount(); 2-$bh
if(totalRecords == 0) [j=,g-EOA
throw new ObjectNotFoundException \=w'HZH#+
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("userNotExist"); V{T{0b"\U
page = PageUtil.createPage(page, totalRecords); c>R`jb@$N
List users = userDAO.getUserByPage(page); `
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returnnew Result(page, users); { p!_-sL
} "^9[OgE:
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} B|Fl,55
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Q;$
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s;fVnaqG:
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查
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询,接下来编写UserDAO的代码: JcTp(fnW.~
3. UserDAO 和 UserDAOImpl: IPl@ DH
java代码: $nB-ADRu@
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/*Created on 2005-7-15*/ $?FS00p*|X
package com.adt.dao; 7$!`p,@we/
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import java.util.List; ="uKWt6n'
V I6\
import org.flyware.util.page.Page; M"=8O>NZ2
CY*ngi &
import net.sf.hibernate.HibernateException; EKZ$Q4YE
s<A*[
/** Q~fwWp-J
* @author Joa hq/J6 M
*/ )t|^Nuj8
publicinterface UserDAO extends BaseDAO { )n\*ht7
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publicList getUserByName(String name)throws i(Ip(n
JN9^fR09G
HibernateException; XzlKP;r0
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publicint getUserCount()throws HibernateException; `IEq@Wr#$!
79)A%@YHQQ
publicList getUserByPage(Page page)throws B0f_kH~p~
"'['(e+7
HibernateException; =2^Vgc
}qc#lz
} `S"W8_m
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java代码: [NYj.#,oR
IE&_!ce
JXpoCCe
/*Created on 2005-7-15*/ >|wKXz
package com.adt.dao.impl; - #3{{
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import java.util.List; ?n!lUr$:y
4\p$4Hs}
import org.flyware.util.page.Page; \% }raI;Y@
!G7h9CF|{
import net.sf.hibernate.HibernateException; Y4QLs^IdB
import net.sf.hibernate.Query; >@^<S_KVh
RnHQq'J|\
import com.adt.dao.UserDAO; as>:\hjP##
d
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/** 9160L qY
* @author Joa b.QpHrnhtK
*/ vFTXTbt'h
public class UserDAOImpl extends BaseDAOHibernateImpl A2Q[%A
:~yzDk\I"-
implements UserDAO { CE)*qFs
:`D'jF^S
/* (non-Javadoc) L>SZgmV+
* @see com.adt.dao.UserDAO#getUserByName 5v"Y\k+1
_-n Y2)
(java.lang.String) Z;hyi'rPJ
*/ d-~vR(tU
publicList getUserByName(String name)throws F&