Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 rhbz|Uq
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }+n|0xK
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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 up'`)s'
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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 __'4Qt
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分页支持类: ih".y3
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java代码: {\D&*
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package com.javaeye.common.util; iVn4eLK^v
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import java.util.List; ")Not$8
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publicclass PaginationSupport { 'JMW.;Lh?X
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publicfinalstaticint PAGESIZE = 30; =0d|F
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privateint pageSize = PAGESIZE; d j\Z}[
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privateList items; lf7bx}P*
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privateint totalCount; 9Vm1q!lE
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privateint[] indexes = newint[0]; 6XWNJb
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privateint startIndex = 0; b!@PS$BTxq
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public PaginationSupport(List items, int a{T.U-0
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totalCount){ ?"9h-g3`x}
setPageSize(PAGESIZE); TM(y%!\
setTotalCount(totalCount); *yRsFC{,
setItems(items); Dm)B? H"
setStartIndex(0); C12UZE;
} ae sk.
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public PaginationSupport(List items, int w li cuY?
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totalCount, int startIndex){ =NtHV4=b
setPageSize(PAGESIZE); JPqd}:u3
setTotalCount(totalCount); %,
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setItems(items); +-@n}xb@
setStartIndex(startIndex);
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} !#)t<9]fv
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public PaginationSupport(List items, int 1p.c6[9-
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totalCount, int pageSize, int startIndex){ 8D )nM|
setPageSize(pageSize); C>+n>bH]L
setTotalCount(totalCount); ,~d0R4)
setItems(items); jjV'`Vy)
setStartIndex(startIndex); \s*M5oN]]
} d. vNiq,`
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publicList getItems(){ %v8&
return items; v@Uk% O/
} }pMVl
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publicvoid setItems(List items){ .kBkYK8*t
this.items = items; <t"T'\3
} q~R8<G%YK
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publicint getPageSize(){ *<xu3){:c
return pageSize; uslu-|b!%
} "@nH;Xlq
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publicvoid setPageSize(int pageSize){ l/G+Xj4M
this.pageSize = pageSize; dxs5woP
} %VO+\L8Fs
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publicint getTotalCount(){ h:8P9WhWF
return totalCount; N5 5F5
} :VT%d{Vp_
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publicvoid setTotalCount(int totalCount){ !XtG6ON=
if(totalCount > 0){ r1r$y2v~
this.totalCount = totalCount; ?wB_fDb}
int count = totalCount / ~b~Tq
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pageSize; Uqel
UL}
if(totalCount % pageSize > 0) wb.yGfJ
count++; _aFe9+y
indexes = newint[count]; {cs>Sy
4
for(int i = 0; i < count; i++){ M~2Us{ `
indexes = pageSize * kg^0 %-F
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i; NuQ!huh
} s>J5.Z7"'j
}else{ F\DiT|?}
this.totalCount = 0; VP#KoX85
} C .S BJ
} d0 )725Ia
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publicint[] getIndexes(){ nc;eNB
return indexes; sv=U^xI
} |jiIx5qr
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publicvoid setIndexes(int[] indexes){ t.9s4 9P
this.indexes = indexes; XH?//.q
} unFRfec{
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publicint getStartIndex(){ s:tX3X
return startIndex; Z<.&fZ^jS
} \\dUp>1=
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publicvoid setStartIndex(int startIndex){ R0RxcBtG
if(totalCount <= 0) ]<^2B?}
this.startIndex = 0; zQyI4RHG[
elseif(startIndex >= totalCount) hBX*02p
this.startIndex = indexes M3jUnp&
_^BA;S@
[indexes.length - 1]; ^K<3_D>1>
elseif(startIndex < 0) "/zgh
this.startIndex = 0; b{<?E };%
else{ YCDH 0M
this.startIndex = indexes ZHNL~=r}
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[startIndex / pageSize]; , MXU]{
} T<B}Z11R
} o.ZR5 `.
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publicint getNextIndex(){ s/7Z.\
int nextIndex = getStartIndex() + =%m{|HQ`
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pageSize; ^bv^&V&IB
if(nextIndex >= totalCount) 3jAr"xc
return getStartIndex(); fxd+0R;f
else tB4mhX|\
return nextIndex; vxmX5.
} -0^]:
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publicint getPreviousIndex(){ t+U.4mS-
int previousIndex = getStartIndex() - KZ%i&w#<
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pageSize; T01Iu
if(previousIndex < 0) { U;yW)
return0; x-[ItJ% l
else hS,&Nj+
return previousIndex; 1sHjM%
} mXz*Gi
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} uHKEt[PS$
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抽象业务类 #s{^fUN6
java代码: '{ _ X1
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/** F@?-^ E@
* Created on 2005-7-12 inaO{ny y
*/ Rf!v{\
package com.javaeye.common.business; yh
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import java.io.Serializable; N6._Jb
import java.util.List; %+l95Dv1
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import org.hibernate.Criteria;
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import org.hibernate.HibernateException; q\@Zf}
import org.hibernate.Session; ]VjvG};
import org.hibernate.criterion.DetachedCriteria; `E$vWZq}
import org.hibernate.criterion.Projections; dx@dnWRT,
import &G"s!:
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org.springframework.orm.hibernate3.HibernateCallback; 3Q$4`p;
import ;5ki$)v"
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org.springframework.orm.hibernate3.support.HibernateDaoS Tdcc<T
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upport; ,'0#q
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import com.javaeye.common.util.PaginationSupport; B$g\;$G
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public abstract class AbstractManager extends 8m{e,o2.
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HibernateDaoSupport { ~]-n%J$q
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privateboolean cacheQueries = false; U
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privateString queryCacheRegion; v Z9OJrF
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publicvoid setCacheQueries(boolean G?}?>O
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cacheQueries){ dy_Uh)$$|g
this.cacheQueries = cacheQueries; ;O}%SCF7
} f]i"tqoI
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publicvoid setQueryCacheRegion(String I,hw0e
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queryCacheRegion){ 5f7id7SI
this.queryCacheRegion = ^t})T*hM0
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queryCacheRegion; M[`[+5v
} A&M_ J
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publicvoid save(finalObject entity){ A1prYD
getHibernateTemplate().save(entity); "kP,v&n
} a>OYJe
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publicvoid persist(finalObject entity){ 1O`V_d)
getHibernateTemplate().save(entity);
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} YD[HBF)~j
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publicvoid update(finalObject entity){ 7GO9z<m)
getHibernateTemplate().update(entity); _|u}^MLO
} vi}16V84l
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publicvoid delete(finalObject entity){ $rXCNew(
getHibernateTemplate().delete(entity); +KbkdYZ
} b,^ "-r
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;
publicObject load(finalClass entity, yn\c;Z
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finalSerializable id){ _-C/sp^
return getHibernateTemplate().load G*4I;'6
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(entity, id); *F1TZ_GS
} OWibmX
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publicObject get(finalClass entity, }*(_JR4G
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finalSerializable id){ 0;l~B
return getHibernateTemplate().get h}a}HabA
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(entity, id); i F+:j8
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} g8.z?Ia#5Z
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publicList findAll(finalClass entity){ /ugWl99.W
return getHibernateTemplate().find("from %e]G]B%
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" + entity.getName()); ~2k.x*$
} )xy>:2!#Y
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publicList findByNamedQuery(finalString \(pwHNSafk
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namedQuery){ ];k!*lR)
return getHibernateTemplate ![%wM Pp
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().findByNamedQuery(namedQuery); {Phq39g
} 2VY7?1Ab(@
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publicList findByNamedQuery(finalString query, v's1&%sM
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finalObject parameter){ /''=V.-N
return getHibernateTemplate !Wr<T!T
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().findByNamedQuery(query, parameter); 4m<]qw
} OM1Z}%J
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publicList findByNamedQuery(finalString query, JlnmG<WLT
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finalObject[] parameters){ 5! );4+
return getHibernateTemplate =;-C;gn:w
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().findByNamedQuery(query, parameters); d'W2I*Zc<
} y>=Y MD
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publicList find(finalString query){ `+n0a@BVB
return getHibernateTemplate().find &j:e<{@
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(query); / ]8e[t>!f
} ?TpjU*Cxy
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publicList find(finalString query, finalObject F2
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parameter){ ~+1mH
return getHibernateTemplate().find KfjWZ4{v
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(query, parameter); =J1V?x=l@
} pK-tj
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public PaginationSupport findPageByCriteria x[lIib1s
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(final DetachedCriteria detachedCriteria){ ?w(hPUd!2
return findPageByCriteria `n>|rd
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); HK :K~h
} lPR^~&/
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public PaginationSupport findPageByCriteria SY5}Bu#
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(final DetachedCriteria detachedCriteria, finalint pG"wQ
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startIndex){ eHvUgDt
return findPageByCriteria l 8?C[,K%
:jv(-RTI
(detachedCriteria, PaginationSupport.PAGESIZE, C"kfxpCi
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startIndex); s/hgWW$
} #~'d
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public PaginationSupport findPageByCriteria d(|?gN^
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(final DetachedCriteria detachedCriteria, finalint [KR%8[e
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pageSize, 2n3&uvf'TL
finalint startIndex){ f5F-h0HF`[
return(PaginationSupport) bz>\n"'
B0yJ9U= Fj
getHibernateTemplate().execute(new HibernateCallback(){ C5^WJx[
publicObject doInHibernate 8TpYt)]S
((`\i=-o5
(Session session)throws HibernateException { Z&>Cdgt*
Criteria criteria = ?jz\[0)s
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detachedCriteria.getExecutableCriteria(session); atpHv**D<i
int totalCount = T/ ECW
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((Integer) criteria.setProjection(Projections.rowCount FiMM-c|
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()).uniqueResult()).intValue(); gd
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criteria.setProjection Rw
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[{2v}
(null); mTsyVji8
List items = k~AtnI
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criteria.setFirstResult(startIndex).setMaxResults Vj4 h#NN$
564L.^$@|
(pageSize).list(); Jf4`
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PaginationSupport ps = q`PA~C];
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new PaginationSupport(items, totalCount, pageSize, 445JOP
_*UI}JtlS
startIndex); :q3w;B~
return ps; B`)sc ~u
} !2Ompcr1
}, true); 1\,k^Je7
} H0&wn#);6R
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public List findAllByCriteria(final =c\(]xX
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate J>#hu3&UOQ
^ U,iDK_
().execute(new HibernateCallback(){ @8{8|P
publicObject doInHibernate o5J6Xi0+
i. )^}id
(Session session)throws HibernateException { tJu:N'=Dy
Criteria criteria = m7NWgXJ
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detachedCriteria.getExecutableCriteria(session); S -mpob)
return criteria.list(); H.|I|XRG/
} BegO\0%+
}, true); vTFG*\Cq
} F&uiI;+zJ
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public int getCountByCriteria(final YGPb8!
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DetachedCriteria detachedCriteria){ <w}^Z}fpk&
Integer count = (Integer) xO:h[
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getHibernateTemplate().execute(new HibernateCallback(){ 4u*n7di$9d
publicObject doInHibernate !pU^?Hy=
l[_antokn
(Session session)throws HibernateException { >Z*b0j
Criteria criteria = ZDaHR-%Y
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detachedCriteria.getExecutableCriteria(session); ]e-QNI
return s%y<FXUj
[)}P{y
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criteria.setProjection(Projections.rowCount jA {BG_
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()).uniqueResult(); TU)Pi.Aa
} kF'9@*?J
}, true); qbSI98rw
return count.intValue(); g$C]ln>"9m
} 3pML+Y|ij
} p=UW ^95
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用户在web层构造查询条件detachedCriteria,和可选的 l'[;q '
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~pp<
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PaginationSupport的实例ps。 i[LnU#+
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ps.getItems()得到已分页好的结果集 4y}z+4
ps.getIndexes()得到分页索引的数组 [ <d~b*/
ps.getTotalCount()得到总结果数 =e
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ps.getStartIndex()当前分页索引 ea @
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ps.getNextIndex()下一页索引 7;@YR
ps.getPreviousIndex()上一页索引 Q)4[zStR#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 > .}G[C
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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 B>'J5bZsw
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一下代码重构了。 e`][zx
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我把原本我的做法也提供出来供大家讨论吧: s\3]0n9
/|NyO+Io
首先,为了实现分页查询,我封装了一个Page类: c99|+i50
java代码: gO*Gf2AG
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/*Created on 2005-4-14*/ ]3|h6KWq
package org.flyware.util.page; Pl|I{l*o(`
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/** SF:{PgGMi
* @author Joa w<!&%
* SkipPEhA
*/ COWlsca
publicclass Page { OY|9V
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/** imply if the page has previous page */ IeChz d
privateboolean hasPrePage; ,1|=_M31
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/** imply if the page has next page */ n&]J-^Tx
privateboolean hasNextPage; t:lDFv4s
B
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/** the number of every page */ hC{2LLu;n
privateint everyPage; q4@+Pi)
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/** the total page number */ -$%~EY}
privateint totalPage; 9\Rk(dd
wrCV&2CG
/** the number of current page */ 7 v3%dCvf
privateint currentPage; aB G*
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/** the begin index of the records by the current b;;y|H
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query */ S=<
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privateint beginIndex; #0*I|gfV
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/** The default constructor */ V^.Z&7+E`_
public Page(){ LM"b%
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} |C+
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/** construct the page by everyPage %^I 7=
* @param everyPage R. ryy
* */ P:'y}a-
public Page(int everyPage){ <;b
this.everyPage = everyPage; 7~MWp4.
} ByWad@-6i
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/** The whole constructor */ yYk?K<ou
public Page(boolean hasPrePage, boolean hasNextPage, T8T,G4Q
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k
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int everyPage, int totalPage, bDw\;bnG
int currentPage, int beginIndex){ b1e)w?n
this.hasPrePage = hasPrePage; :SF8t` 4`
this.hasNextPage = hasNextPage; R*dXbI&,e
this.everyPage = everyPage; Ax!@vL&@
this.totalPage = totalPage; ^CDh! )
this.currentPage = currentPage; Bt\V1 )
this.beginIndex = beginIndex; I.6#>=
} =`(\]t"I
aQ 6T2bQ
/** /xA`VyHO
* @return h*[sV
* Returns the beginIndex. W89J]#v)k
*/ .d)H2X
publicint getBeginIndex(){ wE <PXBl\b
return beginIndex; {2|sk9?W
} jI}{0LW&F&
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/** #zd}xla0]
* @param beginIndex @yPI$"Ma
* The beginIndex to set. V3pn@'pr
*/ =8qhK=&]
publicvoid setBeginIndex(int beginIndex){ Mr K?,7*Xi
this.beginIndex = beginIndex; {\!@k\__
} \w{fq+G
$/JnYkL{m
/** oB}rd9
* @return 8=sMmpB 7u
* Returns the currentPage. g'eJN
*/ 4~:D7",Jn
publicint getCurrentPage(){ s.}:!fBk
return currentPage; ~]K<Vh`
} 7XIG ne%v
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/** 8\Z/mU*4
* @param currentPage g5&,l
* The currentPage to set. 0jefV*3qpB
*/ '-X913eG!
publicvoid setCurrentPage(int currentPage){ j7&0ckN&G
this.currentPage = currentPage; MdNV3:[ \
} oxqD/fY
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/** 5HbPS%^.
* @return Vuo 8[h>
* Returns the everyPage. n)teX.ck)
*/ A832z`
publicint getEveryPage(){ pK2n'4
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return everyPage; _UeIzdV9
} 0l %|2}a
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/** w~9=6|_
* @param everyPage {I_I$x_
* The everyPage to set. m`ab5<%Gn
*/ (V~PYf%
publicvoid setEveryPage(int everyPage){ |a Ht6F
this.everyPage = everyPage; Wr;?t!
} p>]2o\["
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/** o[eIwGxZ
* @return j]_"MMwk$<
* Returns the hasNextPage.
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*/ bPdbKi{j@
publicboolean getHasNextPage(){ ut^^,w{o>
return hasNextPage; 3UX} )mW
} =G2A Ufn
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/** Bx&wS|-) D
* @param hasNextPage D3%`vqu&
* The hasNextPage to set. vo DTU]pf
*/ 'roZ:NE
publicvoid setHasNextPage(boolean hasNextPage){ x-{awP
this.hasNextPage = hasNextPage;
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} ((%g\&D
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/** M%2F7 FY
* @return .@ElfPP(L
* Returns the hasPrePage. #G ZGk?
*/ APksY!
publicboolean getHasPrePage(){ &ExYul
return hasPrePage; _7zER6#}
} d6k`=Hlg
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/** G" Fd]'
* @param hasPrePage ]jS+ItL@
* The hasPrePage to set. k/#& ]8(
*/ m<;&B
publicvoid setHasPrePage(boolean hasPrePage){ sf5koe
this.hasPrePage = hasPrePage; IZ6[|Ach6
} +H
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/** .ZrQ{~t
* @return Returns the totalPage. ^dR5fAS
* &H{KXX"X
*/ d98ZC+q
publicint getTotalPage(){ }A"%YDrNbG
return totalPage; LJMw-#61sj
} s],+]<qX
k w!1]N
/** 0: (@Y
* @param totalPage Q
pY: L
* The totalPage to set. $fY4amX6Z
*/ rX#}2
publicvoid setTotalPage(int totalPage){ 5sq#bvfJ o
this.totalPage = totalPage; LPk85E
} @`ttyI^1f
*5#Y[c
} ZIx,?E+eJ
_6
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vxo iPqo
/*lSpsBn
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Ui46p
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个PageUtil,负责对Page对象进行构造: |!)3[<.
java代码: {=><@]N
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/*Created on 2005-4-14*/ V4!RUqK
package org.flyware.util.page; fD<3Tl8U0
}IGr%C(3%
import org.apache.commons.logging.Log; kN>AY'1
import org.apache.commons.logging.LogFactory; G?MNM -2
j%KLp4J/e
/** W<3nF5!
* @author Joa Ov)rsi
* A|YqBl
*/ vF;%#P
publicclass PageUtil { 4y+]V~p
7@m
privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); h"')D
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/** c;ELAns>
* Use the origin page to create a new page >b0e"eGt
* @param page ^6ZA2-f/<8
* @param totalRecords v>$GVCY
* @return EpCUL@+
*/ Mnaoh:z
publicstatic Page createPage(Page page, int SN'LUwaMp!
2`l$uEI3oJ
totalRecords){ F#Oqa^$(
return createPage(page.getEveryPage(), Eq.?Ga
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page.getCurrentPage(), totalRecords); 5_nkN`x
} b'^-$
g R(*lXm5w
/** M,PZ|=V6a
* the basic page utils not including exception BjJ$I^
t.>vLzrU
handler >b |l6#%
* @param everyPage yKa}U!$
* @param currentPage lBL;aTzo
* @param totalRecords ^ ;$f-e
* @return page ]5'
*/
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publicstatic Page createPage(int everyPage, int 9QI\[lT&
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~
currentPage, int totalRecords){ <Dt,FWWkv'
everyPage = getEveryPage(everyPage); s0.yPA
currentPage = getCurrentPage(currentPage); Hi9 ;i/
int beginIndex = getBeginIndex(everyPage, RIM"MR9qe=
|]]Xee]
currentPage); Zi2NgVF
int totalPage = getTotalPage(everyPage, C 9,p-
vu YH+
totalRecords); t4UKG&[a
boolean hasNextPage = hasNextPage(currentPage, iR(A^
{`~{%2ayq7
totalPage); NJ7N*
boolean hasPrePage = hasPrePage(currentPage); ^gh/$my;
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returnnew Page(hasPrePage, hasNextPage, wI}5[m
everyPage, totalPage, E'&UWDh
currentPage, 'e\m6~u\hm
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beginIndex); oWo"`"P
} VA)3=82n
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privatestaticint getEveryPage(int everyPage){ |z|5j!Nfh
return everyPage == 0 ? 10 : everyPage; l0u6nGkh
} _4rb7"b1
L;5jhVy
privatestaticint getCurrentPage(int currentPage){ co<){5zOT
return currentPage == 0 ? 1 : currentPage; 7vcYI#(2
Y
} klKAwC Q,
@
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privatestaticint getBeginIndex(int everyPage, int )-[ 2vhXz
]ODC+q1
currentPage){ fh
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return(currentPage - 1) * everyPage; IJo`O
} ?a~=CC@
PQXyu1
privatestaticint getTotalPage(int everyPage, int [FC7+
Ey^
0: h;ots'
totalRecords){ RoLUPy9U
int totalPage = 0; ]^&DEj{
<{YP=WYW
if(totalRecords % everyPage == 0) hn.9j"
totalPage = totalRecords / everyPage; |RwD]2H
else ,u{d@U^)3@
totalPage = totalRecords / everyPage + 1 ; bu%@1:l
)Bl% {C
return totalPage; pt(GpbtWK
} zV4%F"-
[t<^WmgtxL
privatestaticboolean hasPrePage(int currentPage){ #'^p-Jdm
return currentPage == 1 ? false : true; IL}pVa00{n
} Q9 kKk
A`=ESz
privatestaticboolean hasNextPage(int currentPage, 27E6S)zv
dj?.Hc7od
int totalPage){ /!JpmI
return currentPage == totalPage || totalPage == M[R, m_p
S]9:3~
0 ? false : true; phbdV8$L
} Zx55mSfx:
8S@ ~^D
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} EFf<|v
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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。 |vTirZP
5D-xm$8C
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 K,|Gtaa~
s3_i5,y
做法如下: Z=R>7~H
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 (~}yt .7K
=d7 lrx+z
的信息,和一个结果集List: zBB4lC{q
java代码: "KW\:uc /
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u
/%Rz`}
/*Created on 2005-6-13*/ g*-
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package com.adt.bo; i <bFF03*S
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import java.util.List; &]pW##
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import org.flyware.util.page.Page; A:p7\Kp;5}
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/** z6|P]u
* @author Joa E} Uy-
*/ }/(fe`7:
publicclass Result { ?*4&Z.~J
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private Page page; 8\. #
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private List content; o*f7/ZP1o
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/** /r[0Dw
* The default constructor 'e7<&wm ia
*/ 8Th|'
public Result(){ A37Z;/H~k
super(); 3,oFT
} 1-r1hZ-
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/** zJ3{!E}`v
* The constructor using fields &Zd{ElM
* "p#mNc
* @param page hKQT,
* @param content Z)62/`C)
*/ C%}FVO\c
public Result(Page page, List content){ ;|soc:aH
this.page = page; o8
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this.content = content; :~zK0v"
} 9i yNR!
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/** 7AV !v`
* @return Returns the content. u{ JAC!
*/ ud'r?QDM
publicList getContent(){ f/*Xw {s#
return content; NLoJmOi;L7
} rm+|xvZ4
9N5&N3
/** `cy_@Z5A
* @return Returns the page. +7^%fX;3pW
*/ =MB[v/M59w
public Page getPage(){ mAk)9`f/
return page; |"5NI'X?
} eDX{}Dq(
6n
/** y''`73U"
* @param content p8%x@%k
* The content to set. FGzB7w#
*/ $MfHA~^
public void setContent(List content){ `L]cJ0tAs
this.content = content; rzLpVpTaz
} Y71io^td~j
*]W{83rXQ
/** w/~,mzM"
* @param page #If}P$!
* The page to set. dF5EIPl;J
*/ 9p+DAs{i
publicvoid setPage(Page page){ CbS- Rz:
this.page = page; D;.-e
} n0>#?ek12
} 9y>dDNM\<
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s34{\/'D+
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S'9T>&<Kn
2. 编写业务逻辑接口,并实现它(UserManager, / /3iai
FU;Tv).
UserManagerImpl) r_@;eh
java代码: M//q7SHh
,=Xr'7w,
rs]%`"&=
/*Created on 2005-7-15*/ g&`e2|[7
package com.adt.service; !X`
5
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import net.sf.hibernate.HibernateException; (5cc{zKtR
8jMw7ti
import org.flyware.util.page.Page; %qV=PC
4sP0oe[h
import com.adt.bo.Result; Xg^`fRg =T
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/** X#Y0g`muW
* @author Joa 8uP,#D<wZ
*/ GXr9J rs.e
publicinterface UserManager { K#%L6=t$<
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public Result listUser(Page page)throws W.r0W2))(
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HibernateException; V\W?@V9g-
d/v{I
} SGXXv
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X#EMmB!
ONH!ms(kb
java代码: AME3hA
s{(aW5$!s
cV\(Z6u
/*Created on 2005-7-15*/ xdFm-_\-
package com.adt.service.impl; |F=!0Id<
YiJnh47
import java.util.List; }%c2u/PQ
^
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import net.sf.hibernate.HibernateException; O:IU|INq8
ai)S:2
import org.flyware.util.page.Page; f*,jhJ_I
import org.flyware.util.page.PageUtil; j1Fy'os"!
uUB,OmLN
import com.adt.bo.Result; v*Ds:1"H-I
import com.adt.dao.UserDAO; 4w\
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`@
import com.adt.exception.ObjectNotFoundException; )a
AKO`
import com.adt.service.UserManager; -*~= 4m<
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/** ]P;uQ!
* @author Joa z#ab
V1
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*/ i ?&t@"'
publicclass UserManagerImpl implements UserManager { twv|,kM
48hu=,)81*
private UserDAO userDAO; =iW!Mq
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/** $N'AZY]4]
* @param userDAO The userDAO to set. ]-QY,
k
*/ ,pM~Phmp
publicvoid setUserDAO(UserDAO userDAO){ Zyt,D|eWj
this.userDAO = userDAO; HY0q!.qog
} hiq7e*Nsb
DDxbIkt
/* (non-Javadoc)
Yz(k4K
L
* @see com.adt.service.UserManager#listUser M<s16
4[m})X2(
(org.flyware.util.page.Page) /j/,@,lw7z
*/ 7?!A~Seo|
public Result listUser(Page page)throws F0:|uC4
$\M<gW6
HibernateException, ObjectNotFoundException {
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int totalRecords = userDAO.getUserCount(); 6_]-&&Nr
if(totalRecords == 0) 4Vl_vTz{i
throw new ObjectNotFoundException FJXYKpY[r
I
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("userNotExist"); @32~#0a
page = PageUtil.createPage(page, totalRecords); I,TJV)B
List users = userDAO.getUserByPage(page); ,cZhkXd
returnnew Result(page, users); l/1u>'
} GKT2x '(e
Fa<>2KkOr
} W!vN(1:(
wNo2$>*
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/kV3[Rw+
Zk,`
Iq
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 kt`_n+G
BIGln`;,f
询,接下来编写UserDAO的代码: wJyrF
3. UserDAO 和 UserDAOImpl: tpu2e*n-|
java代码: |osu4=s|
XJg8-)T#
rPhx^
QKH2
/*Created on 2005-7-15*/ PD #9Z=Hj
package com.adt.dao; Dl=9<:6FW
=og>& K
import java.util.List; KaVNRS
DJ_[{WAV
import org.flyware.util.page.Page; wcr3ugvT
s%M#
import net.sf.hibernate.HibernateException; W*J_PL9j
PLD&/SgP*
/** kw)("SQ
* @author Joa bfo..f-0/Y
*/ v.iHgh
publicinterface UserDAO extends BaseDAO { kN7JZ12
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publicList getUserByName(String name)throws SeuC7!q{
+cH,2 ^&
HibernateException; di.yh3N$
-R%T Dx
publicint getUserCount()throws HibernateException; (~>uFH
=MR.*m{
publicList getUserByPage(Page page)throws MoAie|MKe
jr/
HibernateException; #(@!:f1
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cK>@l
} y;Ez|MS
@*?)S{8
/my5s\;s|z
')R+Z/hG.
w8=&rzr8
java代码: Vn&{yCm3
cp1-eR_&
/80H.|8O
/*Created on 2005-7-15*/ ]MD,{T9l\>
package com.adt.dao.impl; zM+4<k_dH]
LZ#=Ks
import java.util.List; pbCj
^
{ 6
#Qm7s-
import org.flyware.util.page.Page; -VZn`6%s
DWv(|gO
import net.sf.hibernate.HibernateException; Lql2ry$Wa
import net.sf.hibernate.Query; ^aG$9N<\
e
p jb
import com.adt.dao.UserDAO; 7e NLs
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/** [^Z)f<l
* @author Joa 2[!3!@.
*/ u+/Uc:XK)
public class UserDAOImpl extends BaseDAOHibernateImpl {c
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implements UserDAO { J\@|c.ws
[}Q_T.4)E
/* (non-Javadoc) p9>{X\eT:
* @see com.adt.dao.UserDAO#getUserByName ^fiJxU
GLO%>&
(java.lang.String) y+\kZIqX
*/
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publicList getUserByName(String name)throws 8H'ybfed
DCsamOA~
HibernateException { *S xDwN
String querySentence = "FROM user in class awXK9}.
+3yG8
com.adt.po.User WHERE user.name=:name"; L@5sY0 M
Query query = getSession().createQuery }SfS\b{|~
noNJ+0S
(querySentence); M)F_$
ICE-
query.setParameter("name", name); c,2OICj
return query.list(); tJG+k)EE
} g6
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mjQZ"h0
/* (non-Javadoc) 3S 5`I9I
* @see com.adt.dao.UserDAO#getUserCount() ! k[JP+;
*/ *{_N*p\{
publicint getUserCount()throws HibernateException { ^h$^j
int count = 0; [vGkr" =
String querySentence = "SELECT count(*) FROM
O~Jm<