Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Geq]wv8
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1VJ${\H]
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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 $.`o
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 p'jc=bL E
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分页支持类: (D>_O$o
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java代码: {-Y;!
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package com.javaeye.common.util; ',EI[
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import java.util.List; ]oGd,v X
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publicclass PaginationSupport { :j&enP5R(q
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publicfinalstaticint PAGESIZE = 30; xUdF.c
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privateint pageSize = PAGESIZE; s$M(-"mg
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privateList items; (y9KO56.V&
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privateint totalCount; &n<YmW?"
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privateint[] indexes = newint[0]; 6`e{l+c=F
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privateint startIndex = 0; 6 >kU Lp
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public PaginationSupport(List items, int D+7xMT8pqH
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totalCount){ aXe&c^AR
setPageSize(PAGESIZE); NUsxMhP
setTotalCount(totalCount); :c*"Dx'D
setItems(items); tMl y*E
setStartIndex(0); e9LX0=
} ~`
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public PaginationSupport(List items, int i2<z"v63
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totalCount, int startIndex){ 5 ^{~xOM5
setPageSize(PAGESIZE); *Soi
setTotalCount(totalCount); Tz,-~ mc
setItems(items); `O\>vn
setStartIndex(startIndex); ;<+efYmyc
} zx#Gm=H4
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public PaginationSupport(List items, int 't<iB&wgF
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totalCount, int pageSize, int startIndex){ A]BeI
setPageSize(pageSize); Zl>SeTjB-
setTotalCount(totalCount); R~g|w4a@sC
setItems(items); ^+(5[z
setStartIndex(startIndex); Z ]A
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} Zmu
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publicList getItems(){ MzvhE0ab
return items; '{d_q6,%
} mb*Yw6q
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publicvoid setItems(List items){ o0r&w;!
this.items = items; k{*EoV[.$
} //8W"> u
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publicint getPageSize(){ u&~Xgq5[
return pageSize; J^+w]2`S
} F,_L}
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publicvoid setPageSize(int pageSize){ v47' dC
this.pageSize = pageSize; ".}R$W
} WuK<?1meN
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publicint getTotalCount(){ e:G~P
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return totalCount; ai 4 k?
} eT%x(P
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publicvoid setTotalCount(int totalCount){ k^7!iOK2
if(totalCount > 0){ W?Z>g"
this.totalCount = totalCount; ILuQ.VhBVN
int count = totalCount / (;fJXgj.
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pageSize; dDS{XR
if(totalCount % pageSize > 0) Xqf\}p n
count++; ANm@$xO*
indexes = newint[count]; yi8vD~aA[
for(int i = 0; i < count; i++){ QSaDa@OV
indexes = pageSize * b!H1|7>
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} \S h/<z
}else{ Tg)F.):
this.totalCount = 0; 2|k$Vfz
} {\>4)TA
} -VohU-6 |
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publicint[] getIndexes(){ ;0eVE
return indexes; &g?GF\Y
} g1t6XVS$9
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publicvoid setIndexes(int[] indexes){ ld(60?z>FH
this.indexes = indexes; i9 aR#
} I[E 6N2
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publicint getStartIndex(){ Ug*B[q/
return startIndex; Jxl'!8t
} WsbVO|C
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publicvoid setStartIndex(int startIndex){ ]t<=a6<P
if(totalCount <= 0) &A
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this.startIndex = 0; EC,,l'%a|/
elseif(startIndex >= totalCount) hk
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this.startIndex = indexes ;Tbo \Wp9
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[indexes.length - 1]; *k(FbZ
elseif(startIndex < 0) 4j3q69TZR
this.startIndex = 0; 59nRk}^$se
else{ jwwRejNV
this.startIndex = indexes Q7x[08TI
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[startIndex / pageSize]; kw59`z Es
} ]j0+4w
} {^oohW -
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publicint getNextIndex(){ ~2*LWH*@
int nextIndex = getStartIndex() + r
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pageSize; /J^dzvH
if(nextIndex >= totalCount) 23CvfP
return getStartIndex(); !WXV1S
else ,OlS>>,
return nextIndex; +VVn@=&?
} ">T\]V$R
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publicint getPreviousIndex(){ IWYQ67Yj
int previousIndex = getStartIndex() - k*_Gg
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pageSize; O#.YTTj
if(previousIndex < 0) =?|$}vDO[
return0; pbKmFweq
else (pH)QG
return previousIndex; {n>.Y-=
} 8`S1E0s
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} @Yt394gA%\
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抽象业务类 ]6(%tU
java代码: yoGG[l2k>s
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/** $j,$O>V
* Created on 2005-7-12 f5//?ek
*/ a)lCp
package com.javaeye.common.business; 6}Y==GPt
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import java.io.Serializable; H%vgPQ8
import java.util.List; nU=
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import org.hibernate.Criteria; nHF66,7t
import org.hibernate.HibernateException; Gt{%O>P8t
import org.hibernate.Session; {_tq6ja-<
import org.hibernate.criterion.DetachedCriteria; 0J?443AY
import org.hibernate.criterion.Projections; @V>]95RX
import Yv=L'0K&
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org.springframework.orm.hibernate3.HibernateCallback; Qz=e'H
import 4wv0~T$;x
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org.springframework.orm.hibernate3.support.HibernateDaoS =zH)R0!eG
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upport; )z&C&Gqz
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import com.javaeye.common.util.PaginationSupport; 8'E7Uj
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public abstract class AbstractManager extends # [i3cn
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HibernateDaoSupport { - 5v{p
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privateboolean cacheQueries = false; R{[v#sF >#
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privateString queryCacheRegion; +PBl3
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publicvoid setCacheQueries(boolean S*n5d >;
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cacheQueries){ p%iZ6H>G
this.cacheQueries = cacheQueries; tVf):}<h
} x _kT
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publicvoid setQueryCacheRegion(String 7*K2zu3
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queryCacheRegion){ C/
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this.queryCacheRegion = Zk~Pq%u
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queryCacheRegion; % dtn*NU
} qOmL\'8
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publicvoid save(finalObject entity){ g?iZ RM
getHibernateTemplate().save(entity); Gv]94$'J9
} ]w,|WZm
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publicvoid persist(finalObject entity){ ;TC]<N.YJT
getHibernateTemplate().save(entity); cSv;HN:
} E3{kH
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publicvoid update(finalObject entity){ Hi2JG{i
getHibernateTemplate().update(entity); @/N]_2@8;
} &hZ.K"@7{
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publicvoid delete(finalObject entity){ #lik: ?
getHibernateTemplate().delete(entity); OW6dK#CFt
} _J2?B?S/j
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publicObject load(finalClass entity, %jx<<hW
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finalSerializable id){ >`[+24e
return getHibernateTemplate().load #zgO_H
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(entity, id); -ert42fN
} ,+Ocb-*
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publicObject get(finalClass entity, [uJS.`b
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finalSerializable id){ =/xx:D/
return getHibernateTemplate().get mm*nXJ
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(entity, id); 4Q1R:Ra
} X]2x0
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publicList findAll(finalClass entity){ kZ6:=l
return getHibernateTemplate().find("from iZ/iMDfC
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" + entity.getName()); UCj<FN `
} OrL4G
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publicList findByNamedQuery(finalString @o1#J`rv
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namedQuery){ gw">xt5
return getHibernateTemplate NBBR>3nt
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().findByNamedQuery(namedQuery); 4M0p:Ey '
} RkTYvAk|kY
![4_K':=
publicList findByNamedQuery(finalString query, OaT]2o
}fef* >>}
finalObject parameter){ X>pCkGE
return getHibernateTemplate "1>w\21
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().findByNamedQuery(query, parameter); =j20A6gND
} {~#PM>f
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publicList findByNamedQuery(finalString query, WAtv4
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finalObject[] parameters){ {wk#n.c
return getHibernateTemplate e\-,e+
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().findByNamedQuery(query, parameters); C%ZPWOc_8
} CQmozh-
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publicList find(finalString query){ \J#&]o)Y
return getHibernateTemplate().find
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uvR l`"Y
(query); *c%{b3T_
} Hj `\Fm*A
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publicList find(finalString query, finalObject 9s7TLT k
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parameter){ e_l|32#/
return getHibernateTemplate().find (!efaj
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(query, parameter); 4MzPm~Ct
} }}rp/16
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public PaginationSupport findPageByCriteria tv~Y5e&8
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(final DetachedCriteria detachedCriteria){ t.\Pn4
return findPageByCriteria eR`Q7]j] -
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); c4Q9foE
} Eg}U.ss^
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public PaginationSupport findPageByCriteria 1*6xFn
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(final DetachedCriteria detachedCriteria, finalint H?ug-7k/
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startIndex){ pp{p4Z
return findPageByCriteria V[Sj+&e&
a2]ZYY`R7
(detachedCriteria, PaginationSupport.PAGESIZE, CY*GCkH
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startIndex); O.\\)8xA
} 4#:Eq=(W
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public PaginationSupport findPageByCriteria _ShWCU-~Z
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(final DetachedCriteria detachedCriteria, finalint @,2,(=l*C
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pageSize, 0%q H=do6
finalint startIndex){ @SaxM4
return(PaginationSupport) 9KJ}Ai
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getHibernateTemplate().execute(new HibernateCallback(){ Eht8~"fj
publicObject doInHibernate H;q[$EUNb
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(Session session)throws HibernateException { })?-)fFD
Criteria criteria = x;/dSfv_
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detachedCriteria.getExecutableCriteria(session); DWCf+4
int totalCount = suFk<^3
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((Integer) criteria.setProjection(Projections.rowCount tGbx/$Y
-okq=9
()).uniqueResult()).intValue(); [7LdTY"Tl
criteria.setProjection Fq
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(null); h^1!8oOYD
List items = Zu>-y#Bw
&RI;!qn6(
criteria.setFirstResult(startIndex).setMaxResults /;[x3}[
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(pageSize).list(); :)T*:51{#
PaginationSupport ps = ;mGPX~38
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new PaginationSupport(items, totalCount, pageSize, mI:^lp
{X_I>)Wg
startIndex); Qgv g*KX
return ps; j+q)
} xdz 6[8d8
}, true); Zg>]!^X8
} guf*>qNr
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public List findAllByCriteria(final xirq$sEl
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DetachedCriteria detachedCriteria){ $d4&H/u^
return(List) getHibernateTemplate h;y}g/HZ
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().execute(new HibernateCallback(){ ~F-lO1
publicObject doInHibernate s16, *;Z
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(Session session)throws HibernateException { @#-\BQ;
Criteria criteria = piuM#+Y\'S
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detachedCriteria.getExecutableCriteria(session); G!G:YVWXP
return criteria.list(); %B1)m A;
} _O11SiP]
}, true); )UTjP/\gN
} qbCU&G|)
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public int getCountByCriteria(final B9KBq$e
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DetachedCriteria detachedCriteria){ ^;9l3P{
Integer count = (Integer) ,oSn<$%/q
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getHibernateTemplate().execute(new HibernateCallback(){ %6Vb1?x
publicObject doInHibernate ^6F, lS _t
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(Session session)throws HibernateException { ?9!9lSH6%
Criteria criteria = I|>.&nb
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detachedCriteria.getExecutableCriteria(session); RP[`\
return eH!V%dX
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criteria.setProjection(Projections.rowCount J7%rPJ
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()).uniqueResult(); j6$@vA)
} #w \x-i|
}, true); t%5bDdo
return count.intValue(); *O @Zn
} =h
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} UJ%.KU%Q}
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用户在web层构造查询条件detachedCriteria,和可选的 CR2.kuM0~
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8'bZR]
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PaginationSupport的实例ps。 FwHqID_!:l
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ps.getItems()得到已分页好的结果集 PVdN)tG5
ps.getIndexes()得到分页索引的数组 9=/4}!.
ps.getTotalCount()得到总结果数 ) R5j?6}xF
ps.getStartIndex()当前分页索引 c93 Ok |
ps.getNextIndex()下一页索引 l,(:~KH|
ps.getPreviousIndex()上一页索引 u*uHdV5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 I*(kv7(c0
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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 >hq{:m
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一下代码重构了。 C2=PGq
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我把原本我的做法也提供出来供大家讨论吧: *<SXzJ(
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首先,为了实现分页查询,我封装了一个Page类: :"Tkl$@,
java代码: O7LJ-M
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/*Created on 2005-4-14*/ +t&)Z
package org.flyware.util.page; _LfbEv<,T
{%^4%Eco
/**
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* @author Joa m?Cb^WgcF
* J&JZYuuf
*/ (e!Yu#-
publicclass Page { 9kqR-T|Q
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/** imply if the page has previous page */ `U\l: ~]e
privateboolean hasPrePage; 5[)#3vY
i!3*)-a\~`
/** imply if the page has next page */ H_x}-
privateboolean hasNextPage; ./0wt+
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/** the number of every page */ Ars*H,9>e
privateint everyPage; QkHG`yW
+|pYu<OY
/** the total page number */ P0hr=/h4
privateint totalPage; ~!7x45(1#
'o0o.&/=
/** the number of current page */ ~dLbhjden
privateint currentPage; M}CxCEdDB]
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/** the begin index of the records by the current g=qaq
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query */ <Uf`'X\e6
privateint beginIndex; cT/mi":8{
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/** The default constructor */ k2,`W2]^E
public Page(){ 0nB[Udk?
}-XZ1qr
} O#O"]A
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/** construct the page by everyPage CRNi*u
* @param everyPage (RG "2I3
* */ )flm3G2u
public Page(int everyPage){ 8d Fqwpw8
this.everyPage = everyPage; P7bb2"_9
} Ct~j/.
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/** The whole constructor */ X%(NI(+x,
public Page(boolean hasPrePage, boolean hasNextPage, Y{#*;p*I
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int everyPage, int totalPage, K`<HZK
int currentPage, int beginIndex){ >BK/HuS
this.hasPrePage = hasPrePage; _FcTY5."S
this.hasNextPage = hasNextPage; }YM\IPsPu
this.everyPage = everyPage; `{
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this.totalPage = totalPage; S+-$Ih`[
this.currentPage = currentPage; W+U0Y,N6
this.beginIndex = beginIndex; s3Zt)xQ3
} e"bzZ!c&~V
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/** *_#2|96)
* @return 2]5Li/
* Returns the beginIndex. l Ib
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*/ <%m1+%mA.
publicint getBeginIndex(){ }BL7P-km
return beginIndex; f>4|>kS
} %0/qb0N&
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/** 2QAP$f0Ln
* @param beginIndex p8@&(+z
* The beginIndex to set. M<NY`7$^
*/ _-543B}
publicvoid setBeginIndex(int beginIndex){ xfI0P0+
this.beginIndex = beginIndex; Umz b
} UA2KY}pz5
*V\.6,^v
/** (U#
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* @return Mlo,F1'?>
* Returns the currentPage. .`*]nN{
*/ xf,A<j(o
publicint getCurrentPage(){ `aG_ m/7|
return currentPage; !QbuOvw
} ]d7A|)q
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/** `sso Wn4
* @param currentPage e`LkCy[_
* The currentPage to set. _Y]Oloo('
*/ Cojs;`3iF:
publicvoid setCurrentPage(int currentPage){ L97 ~ma
this.currentPage = currentPage; T`Up%5Dk
} BN%cX2j
%*npLDi
/** p}pd&ut1
* @return wuYak"KX
* Returns the everyPage. YG:^gi
*/ _6r[msH"
publicint getEveryPage(){ tD}-&"REP
return everyPage; 6B7*|R>
} NQZ /E )f
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/** 8OV=;aM?{
* @param everyPage G6W|l2P!
* The everyPage to set. PLz+%L;{
*/ K\fD';
publicvoid setEveryPage(int everyPage){ Y%0rji
this.everyPage = everyPage; ")vtS}Ekt
} 2YY4 XHQS
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/** :Rv+Bm
* @return h^Yh~84T
* Returns the hasNextPage. {6RA~
*/ KU
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publicboolean getHasNextPage(){ zx2`0%Q
return hasNextPage; >4kQ9lXL
} D86F5HT}}
4^:dmeMZ`
/** 7 L,`7k|
* @param hasNextPage >Ovz;
* The hasNextPage to set. pt3)yj&XE
*/ f"*4R
kG
publicvoid setHasNextPage(boolean hasNextPage){ 6|f8DX%3V
this.hasNextPage = hasNextPage; y }R2ZO
} t1mG]
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/** *WJK&
* @return - ry
* Returns the hasPrePage. w42{)S"
*/ u?MhK#Mr
publicboolean getHasPrePage(){ MmvOyKNZF
return hasPrePage; *!BQ1] G
} Ank_;jo
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/** dnwzf=+>e
* @param hasPrePage ^b|? ?9&
* The hasPrePage to set. qk3~]</
*/ K8BlEF`
publicvoid setHasPrePage(boolean hasPrePage){ #4LTUVH
this.hasPrePage = hasPrePage; -]u>kjiIT
} <zvtQ^{]
}93FWo.
/** 6]<yR>
'
* @return Returns the totalPage. |4j6}g\
* 7p':a)
*/ G,Eh8HboK
publicint getTotalPage(){ *)^ZUk
return totalPage; ^z,B}Nz
} 0k?]~f
)c9Xp:
/** pG)dF@
* @param totalPage :]Om4Q\-#
* The totalPage to set. GtIAsC03
*/ s Iaehe'B
publicvoid setTotalPage(int totalPage){ yW7>5r
this.totalPage = totalPage; w?nSQBz$
} qyKR]%yzi
$[MAm)c:]{
} [`tNa Vg
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+=|%9%
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m
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 Y|hd!C-x
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个PageUtil,负责对Page对象进行构造: T<Zi67QC@
java代码: 7MJ\*+T|03
+CSR!
j%]sym
/*Created on 2005-4-14*/ wEI?
9
package org.flyware.util.page; u=~`5vA
E1Q#@*rX>
import org.apache.commons.logging.Log; XA. 1Y)
import org.apache.commons.logging.LogFactory; DXO'MZon3
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/** *L*{FnsV
* @author Joa })(robBkA
* KXcRm)
*/ f qWme:x
publicclass PageUtil { mO TA
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privatestaticfinal Log logger = LogFactory.getLog F,pKt.x
la 0:jO5
(PageUtil.class); IFa~`Gf [
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/** wzoT!-_X
* Use the origin page to create a new page PX/^*
* @param page K~3Y8ca
* @param totalRecords pg_H' 0R
* @return unz~vG1Tn
*/ e8(Qx3T?b
publicstatic Page createPage(Page page, int 6jm/y@|F!
P;'ZdZ(SLu
totalRecords){ /!p}H'jl
return createPage(page.getEveryPage(), |_+l D|'
9}fez)m:g0
page.getCurrentPage(), totalRecords); b^}U^2S%
} Q:y'G9b
j:2F97
/** ICe;p
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* the basic page utils not including exception ]8Xip/uE
:+
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handler @g" vuaG}
* @param everyPage mWn0"1C
* @param currentPage eC6wrpZO
* @param totalRecords 7<B-2g
* @return page @*=5a(#
*/ ,69547#o
publicstatic Page createPage(int everyPage, int $2}%3{<j
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currentPage, int totalRecords){ vO/ 3bu}
everyPage = getEveryPage(everyPage); V 7ZGT
currentPage = getCurrentPage(currentPage); ?FR-aXx
int beginIndex = getBeginIndex(everyPage, D$NpyF.87
"oF)u1_?
currentPage); x_C0=Q|K3
int totalPage = getTotalPage(everyPage, {5d 5Y%&
1_Av_X
totalRecords); zf^|H%
~^
boolean hasNextPage = hasNextPage(currentPage, KU]o=\ak%
yg~@}_C2_
totalPage); tp&|*M3
boolean hasPrePage = hasPrePage(currentPage); |z:4T%ES
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returnnew Page(hasPrePage, hasNextPage, G\V*j$}!
everyPage, totalPage, Jo~fri([%Q
currentPage, .|s,':hA
~gNFcJuy
beginIndex); ?~yJ7~3TS<
} E\;%,19Ob
'!,(G3
privatestaticint getEveryPage(int everyPage){ Z{yH:{Vk
return everyPage == 0 ? 10 : everyPage; HSAr6h
} WBm)Q#1:
ae]6F_Qtc*
privatestaticint getCurrentPage(int currentPage){ jh`[Y7RJO
return currentPage == 0 ? 1 : currentPage; 4i+%~X@p
} 0 ]L
i27)c)\BM
privatestaticint getBeginIndex(int everyPage, int Qh-:P`CN
tAI
v+L
currentPage){ 6DgdS5GhT_
return(currentPage - 1) * everyPage; j:/Z_v'
} Qf}.= (
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privatestaticint getTotalPage(int everyPage, int :Q@/F;Z?
Pt/]Z<VL
totalRecords){ }^p<Y5{b
int totalPage = 0; c-n/E. E
(j??
if(totalRecords % everyPage == 0) 5$cjCjY
totalPage = totalRecords / everyPage; R*6B@<p,i
else z0SF2L H
totalPage = totalRecords / everyPage + 1 ; ^m&P0
hh*('n>[
return totalPage; v}d)uPl};
} kV4Oq.E
GdVF;
privatestaticboolean hasPrePage(int currentPage){ N~l*//Ep
return currentPage == 1 ? false : true; ^+CHp(X
} ka8Y+Gs
BK6
X)1R
privatestaticboolean hasNextPage(int currentPage, 0BhcXHt
Ef28
int totalPage){ Yv@n$W`:
return currentPage == totalPage || totalPage == bE'{zU}o
i$PO#}
0 ? false : true; ?6`B;_m
} hd~#I<8;2
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-eyF9++`
} 2Ki_d
X~D[CwA|`
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LSJ.pBl\X
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。 c$7~EP
7H< IO`
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 'o#oRK{#
/]!2k9u\
做法如下: T>rmm7F
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 /3~L#jS
Wtcib-
的信息,和一个结果集List: m x |V)
java代码: bHv"!
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A?!RF7v
/*Created on 2005-6-13*/ 7KhS{w6
package com.adt.bo; DlE, aYB
<a @7's
import java.util.List; .G!xcQ`?
4hwb]
Yz
import org.flyware.util.page.Page; {eaR,d~X
[=q/f2_1.
/** j0; ~2W#G*
* @author Joa jL"V0M]c
*/ hDJG.,r
publicclass Result { 8e*skL
kP&I}RY
private Page page; %(/E
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private List content; xBTx`+%WS
w>^(w<~Y
/** (is' ,4^b
* The default constructor O?Bf (y
*/ fOHbgnL>
public Result(){ '@.6Rd 8
super(); bt) C+|i
} I$t8Ko._"
`5Kg[nB:
/** d/Q#Z
* The constructor using fields Zpkd8@g@
* Nt@|l7Xl*
* @param page SZ9Oz-?
* @param content vF$(
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*/ lfHN_fE>Mq
public Result(Page page, List content){ ?uSoJM`wa!
this.page = page; *HR
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this.content = content; .t1:;H b
} ;^xM"
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/** %@Gy<t,
* @return Returns the content. B.r^'>jQ
*/ D wJ^ W&*
publicList getContent(){ .8|wc
return content; :lB`K>)iB}
} x*vD^1"'P
i|1*bZ6'
/** c1k[)O~
* @return Returns the page. a*5KUj6/TL
*/ (& SU)Uvu
public Page getPage(){ S=r0tao,!v
return page; -13}]Gls7Q
} `#ruZM066
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/** w&L~+Z<
* @param content Ih:Q}V#6
* The content to set. \PxT47[@e
*/ 2V)+ba|+
public void setContent(List content){ 61H_o7XXk
this.content = content; DSwb8q
} y{@\8B]
5K1cPU~o_b
/** 5FR#CQ
* @param page ;|vP|Xi
* The page to set. We{@0K/O
*/ zE/l
publicvoid setPage(Page page){ .m]}Ba}J$
this.page = page; > mO*.' Gm
} \+V"JIStUj
} v`,!wS
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:+/8n+@#
2. 编写业务逻辑接口,并实现它(UserManager, V,rc&97
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UserManagerImpl) ,5$G0
java代码: <Ja&z M
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,7j8+p|},
/*Created on 2005-7-15*/ a5#G48'X
package com.adt.service; lq:q0>vyI
h]s6)tII
import net.sf.hibernate.HibernateException; >}* W$i
/.0K#J:
import org.flyware.util.page.Page; i-wRwl4aEF
o5s6$\"
import com.adt.bo.Result; our
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f`Fj-<v
/** P6GTgQ<'BA
* @author Joa `'s_5Ek
*/ i) e6U(H
publicinterface UserManager { ~k&b
yb',nGl~
public Result listUser(Page page)throws [`GSc6j
}oZ8esZU2
HibernateException; v,}C~L3
W5Z-s.o
} xK6`|/e
E'\gd7t ;
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3
(@}^ 3jpT
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java代码: G06;x
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/*Created on 2005-7-15*/ b~&cYk'
package com.adt.service.impl; D
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import java.util.List; sX6\AYF1M
{oY"CZ2
import net.sf.hibernate.HibernateException; '|]}f }Go
R8[VD iM6E
import org.flyware.util.page.Page; 0 8L;u7u
import org.flyware.util.page.PageUtil; tkV[^OeU>
#D_Ti%.^}
import com.adt.bo.Result; K{_~W yRF
import com.adt.dao.UserDAO; liYsUmjZ=
import com.adt.exception.ObjectNotFoundException; Vw w 211
import com.adt.service.UserManager; Kq")|9=d
sP^:*B0
/** \9,lMK[b
* @author Joa OulRqbL2
*/ 2T*kmDp
publicclass UserManagerImpl implements UserManager { "*#f^/LS
--y,ky#
private UserDAO userDAO; Pa{DB?P
LIG@`
/** 4-[U[JJc
* @param userDAO The userDAO to set. 5P<"I["
*/ &]a(5
publicvoid setUserDAO(UserDAO userDAO){ 8US35t:M
this.userDAO = userDAO; Gs"lmX-{$j
} FMCA~N
W2XWb<QSEV
/* (non-Javadoc) :a Cf@:']
* @see com.adt.service.UserManager#listUser 9K}DmS
TkTGYh
(org.flyware.util.page.Page) fASklcQ
*/ !KXcg9e
public Result listUser(Page page)throws kq=Htbv7
Q#yHH]U)X
HibernateException, ObjectNotFoundException { mH;t)dT
int totalRecords = userDAO.getUserCount(); N_:!uR
if(totalRecords == 0) Lfx a^0
throw new ObjectNotFoundException I`B ZZ-
W=
NX$=il
("userNotExist"); EUt2S_2P
page = PageUtil.createPage(page, totalRecords); G$YF0Nc
List users = userDAO.getUserByPage(page); \68bXY.
returnnew Result(page, users); DOtz
} 2A
LT{g^g
} =UO7!vr;[
]z7pa^
){/n7*#Th%
o&q:b9T
Kc]
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fR;[??NH
Se??E+aX
询,接下来编写UserDAO的代码: Jyd[Sc)
3. UserDAO 和 UserDAOImpl: -"Kjn`8
java代码: Zu#^a|PE*
pPs TgGai
0p3) t
/*Created on 2005-7-15*/ E\4ZUGy0
package com.adt.dao; Q%'4jn?H
BpFXe7
import java.util.List; 4UL"f<7 T
l-IA Q!d
import org.flyware.util.page.Page; Tw/7P~*
} 5"Rj<
import net.sf.hibernate.HibernateException; ]\ZJaU80I~
q=cnY+p>
/** toG- Dz&