Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 );zLgNx,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3
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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 )Dp0swJ
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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 q
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分页支持类: ? G`6}NP
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java代码: _X|prIOb=
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package com.javaeye.common.util; {_mVfFG
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import java.util.List; e#)NYcr6
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publicclass PaginationSupport { d
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publicfinalstaticint PAGESIZE = 30; W4,'?o
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privateint pageSize = PAGESIZE; CBv0fQtL
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privateList items; Ze[,0Y!u&
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privateint totalCount; HB{'MBs
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privateint[] indexes = newint[0]; !,dp/5
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privateint startIndex = 0; O}w%$ mq
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public PaginationSupport(List items, int YS#*#!ZMn?
)Gm9x]SVl
totalCount){ yM `u]p1
setPageSize(PAGESIZE); rvlvk"
setTotalCount(totalCount); '$c9 S[
setItems(items); `yP`5a/
setStartIndex(0); g60k R7;\
} l2kGFgc
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public PaginationSupport(List items, int h!ogH >S~
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totalCount, int startIndex){ |j-ng;
setPageSize(PAGESIZE); Jt[,V*:#
setTotalCount(totalCount); LRg]'?
setItems(items); v3aPHf
setStartIndex(startIndex); B]H8^
} @({=~
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public PaginationSupport(List items, int @gfW*PNjlP
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totalCount, int pageSize, int startIndex){ ,zdGY]$
setPageSize(pageSize); i!RfUod
setTotalCount(totalCount); lm
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setItems(items); =@0J:"c
setStartIndex(startIndex); YVwpqOE.=
} Xl<iR]lda
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publicList getItems(){ 3C<G8*4);/
return items; BM/o7%]n
} l=b!O
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publicvoid setItems(List items){ <gFa@at
this.items = items; vc&v+5Y
} pY@QR?F\
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publicint getPageSize(){ 1f<R,>
return pageSize; J_h.7V
} ol*,&C:{
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publicvoid setPageSize(int pageSize){ F3EAjO)ch
this.pageSize = pageSize; Uns%6o
} :09NZ
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publicint getTotalCount(){ 0F@ ~[W|2
return totalCount; a_V\[V{R=
} _FYA? d}
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publicvoid setTotalCount(int totalCount){ e`s1z|h
if(totalCount > 0){ '9Z`y_~)G
this.totalCount = totalCount; cZQ8[I
int count = totalCount / W~0rSVD$<z
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pageSize; aZ4?!JW .
if(totalCount % pageSize > 0) kqm(D#
count++; O7Jux-E1C
indexes = newint[count]; =`QYy-b X
for(int i = 0; i < count; i++){ uQKQC?w
indexes = pageSize * OemY'M?ZQ
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} V:GypY)
}else{ A4!X{qUT-
this.totalCount = 0; 6{buel(|e
} Wu^Rv- xA
} )gEE7Ex?
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publicint[] getIndexes(){ ?a3wBy
return indexes; aL4^ po
} rP3tFvOH
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publicvoid setIndexes(int[] indexes){ 88~Nrl=co
this.indexes = indexes; ;ND$4$
} X7huc*
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publicint getStartIndex(){ }[;ZZm?
return startIndex; ?E"192,z@
} D[/fs`XES
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publicvoid setStartIndex(int startIndex){ 6X*vCylI
if(totalCount <= 0) s|e.mZk/
this.startIndex = 0; ud r\\5
elseif(startIndex >= totalCount) Yi%lWbr
this.startIndex = indexes (|K+1R
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[indexes.length - 1]; B=TUZ)
elseif(startIndex < 0) oI{.{]
this.startIndex = 0; XnZ$%?$
else{ x<gmDy*
this.startIndex = indexes yws'}{8
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[startIndex / pageSize]; ZKXE7p
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} P!W%KobZ7|
} 7P+1W
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publicint getNextIndex(){ Y7.+
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int nextIndex = getStartIndex() + `s}L3bR]
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pageSize; N!(mM;1X)
if(nextIndex >= totalCount) o>r
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return getStartIndex(); &T,|?0>~=J
else ZOEe -XW
return nextIndex; E+lR&~mK=
} &SE}5ddC7
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publicint getPreviousIndex(){ KVa{;zBwl
int previousIndex = getStartIndex() - E2'Wzrovlo
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pageSize; 1 %P-X!
if(previousIndex < 0) (N9-YP?qm
return0; H54RA6$>
else x#EE_i/W
return previousIndex; KSPa2>lz?
} gB'ajX=OA/
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} ;
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抽象业务类 vTK%4=|1}!
java代码: }ssV"5M
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/** LL#REK|lm8
* Created on 2005-7-12 &u2;S?7m
*/ ,p d-hu
package com.javaeye.common.business; GQtNk<?$I
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import java.io.Serializable; T)\}V#iA*
import java.util.List; UH!(`Z\C
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import org.hibernate.Criteria; W#F9Qw
import org.hibernate.HibernateException; Hh1_zd|
import org.hibernate.Session; XGB\rfvS
import org.hibernate.criterion.DetachedCriteria; @ b!]Jw
import org.hibernate.criterion.Projections; e_=K0fFz
import @wR3L:@
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org.springframework.orm.hibernate3.HibernateCallback; ab2FK
import ]bY|>q
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org.springframework.orm.hibernate3.support.HibernateDaoS MT-Tt
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upport; iwK.*07+
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import com.javaeye.common.util.PaginationSupport; (bb!VVA
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public abstract class AbstractManager extends 7[1Lh'u
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HibernateDaoSupport { /}m)FaAi
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privateboolean cacheQueries = false; 0SI@`C*1o
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privateString queryCacheRegion; L
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publicvoid setCacheQueries(boolean JY"jj}H]|
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cacheQueries){ 2<@2_wSJ
this.cacheQueries = cacheQueries; f;{Q ~
} 1CB&z@
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publicvoid setQueryCacheRegion(String J# (AX6
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queryCacheRegion){ `MU~N_
this.queryCacheRegion = $,}jz.R@
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queryCacheRegion; p / ITg
} "#~>q(4^
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publicvoid save(finalObject entity){ z5jw\jBD
getHibernateTemplate().save(entity); TPN+jK
} bXs=<`>
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publicvoid persist(finalObject entity){ }^&S^N7
getHibernateTemplate().save(entity); ~&<#H+O
} 4CM'I~
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publicvoid update(finalObject entity){ )pHtsd. eP
getHibernateTemplate().update(entity); 1{a%V$S[
} DG;7+2U
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publicvoid delete(finalObject entity){ <w9~T TS
getHibernateTemplate().delete(entity); |oPRP1F-;e
} N9w"Lb
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publicObject load(finalClass entity, (uC8M,I\
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finalSerializable id){ q/ljH_-
return getHibernateTemplate().load ]}v]j`9m%
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(entity, id); p[Po*c.b
} hP"2X"kz&
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publicObject get(finalClass entity, q}LDFsU
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finalSerializable id){ >bW=oTFz
return getHibernateTemplate().get 4mvR]:G
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(entity, id); &r1(1<
} ,CqWm9
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publicList findAll(finalClass entity){ a}UmD
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return getHibernateTemplate().find("from Jy(G
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" + entity.getName()); {+J{t\`
} 1=)M15
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publicList findByNamedQuery(finalString tpJA~!mG3
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namedQuery){ {'IO
return getHibernateTemplate 11oNlgY&
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().findByNamedQuery(namedQuery); _*o<<C\E
} Xz^nm\
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publicList findByNamedQuery(finalString query, .a@12J(I
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finalObject parameter){ KsKE#])&l
return getHibernateTemplate r9ulTv}X
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().findByNamedQuery(query, parameter); Vm%G
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} ~F,~^r!Jtu
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ \;&;K'
return getHibernateTemplate &E&~9"^hQL
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().findByNamedQuery(query, parameters); od)TQSo
} &s".hP6
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publicList find(finalString query){ cUR :a@
return getHibernateTemplate().find ~(R=3
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(query); So1TH%
} `58% &3lp
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publicList find(finalString query, finalObject z8X7Y
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parameter){ n6oOknCna
return getHibernateTemplate().find PBn7{( x
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(query, parameter); h*fN]k6
} M/W"M9u
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public PaginationSupport findPageByCriteria =o9s?vOJ
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(final DetachedCriteria detachedCriteria){ =Kkqk
return findPageByCriteria y RxrfAdS
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); a
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} V}s/knd
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public PaginationSupport findPageByCriteria :BPgDLL,
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(final DetachedCriteria detachedCriteria, finalint (%B{=w}8
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startIndex){
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return findPageByCriteria NTu|cX\R
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(detachedCriteria, PaginationSupport.PAGESIZE, .aNh>`OT'
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startIndex); F=qILwd
} #Pg#\v|7#>
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public PaginationSupport findPageByCriteria 6BV 6<PHJ
@\g}I`_M
(final DetachedCriteria detachedCriteria, finalint UVw^t+n
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pageSize, B=cA$620
finalint startIndex){ 0
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return(PaginationSupport) dEk#"cvg
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getHibernateTemplate().execute(new HibernateCallback(){ @6"MhF
publicObject doInHibernate liS'
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(Session session)throws HibernateException { !P{ /;Q
Criteria criteria = '/I`dj
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detachedCriteria.getExecutableCriteria(session); NZ1B#PG,c
int totalCount = {bXN[=j
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((Integer) criteria.setProjection(Projections.rowCount T~xVHk1
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()).uniqueResult()).intValue(); a[K&;)
criteria.setProjection qraXAQ
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(null); Ir JSU_
List items = g4^-B
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criteria.setFirstResult(startIndex).setMaxResults GN|"RuQ
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(pageSize).list(); |.c4y*
PaginationSupport ps = %NkiY iA
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new PaginationSupport(items, totalCount, pageSize, nuq@m0t\#
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startIndex); h ;uzbu
return ps; YhH3f VM
} zbFy3-R P
}, true); k1z`92"
} hF-QbO
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public List findAllByCriteria(final 4 ?BQ&d
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DetachedCriteria detachedCriteria){ "_UnN}Uk
return(List) getHibernateTemplate j/TnKO
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().execute(new HibernateCallback(){
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publicObject doInHibernate x@Gg fH<l
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(Session session)throws HibernateException { ]+e
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Criteria criteria = (3N/DY1/
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detachedCriteria.getExecutableCriteria(session); .f$2-5q
return criteria.list(); XuP%/\
} 3N > V
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}, true); W"%n5)
} . gy:Pl]w
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public int getCountByCriteria(final @]Vcl"t
sO) H#G
DetachedCriteria detachedCriteria){ |}d^lQ9
Integer count = (Integer) B*G]Dr)e
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getHibernateTemplate().execute(new HibernateCallback(){ 9po=[{Bp
publicObject doInHibernate QP(d77n
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(Session session)throws HibernateException { Pjh;;k|V
Criteria criteria = BZ\="N#f
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detachedCriteria.getExecutableCriteria(session); ]ttF''lH
return g}`g>&l5
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criteria.setProjection(Projections.rowCount gbMA-r:IC
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()).uniqueResult(); ?J$k
5;
} #_ulmB;
}, true); Ho(MO!(
return count.intValue(); mZU
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} #eYYu2ND
} 6KGT?d
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用户在web层构造查询条件detachedCriteria,和可选的 OX.5olb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 | K|AUI
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PaginationSupport的实例ps。 nOyG7:
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ps.getItems()得到已分页好的结果集 t!wbT79/
ps.getIndexes()得到分页索引的数组 pOK=o$1V8
ps.getTotalCount()得到总结果数 X(Af`KOg[
ps.getStartIndex()当前分页索引 6Zpa[,gm
ps.getNextIndex()下一页索引 ot7f?tF2<J
ps.getPreviousIndex()上一页索引 to13&#o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 <nJGJ5JJ
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 dZ"}wKbO
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一下代码重构了。 4r;le5@
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我把原本我的做法也提供出来供大家讨论吧: "u^2!d
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首先,为了实现分页查询,我封装了一个Page类: >CG;df<~
java代码: >#dLT~[\a
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/*Created on 2005-4-14*/ #}.{|'L
package org.flyware.util.page; k4&adX@Y
lYe2;bu
/** @}jg5}
* @author Joa &pl)E$Y
* <.g)?nj1
*/ <Y /3U
publicclass Page { DaH4 Br.2
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/** imply if the page has previous page */ MuO(%.H
privateboolean hasPrePage; j^/<:e c.
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/** imply if the page has next page */ y-@`3hYM@
privateboolean hasNextPage; ^Zpz@T>m
$lB!Q8a$
/** the number of every page */ mr[ 1F]G
privateint everyPage; VB^1wm
4Tuh]5
/** the total page number */ rG-x 3>b
privateint totalPage; bPV}T`
e8SAjl"}
/** the number of current page */ Q$Qr)mcC
privateint currentPage; x15&U\U
"@ZwDg`
/** the begin index of the records by the current k FRVW+
/hg^hF
query */ Q_/UC#I8
privateint beginIndex; Oc~<`C~
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/** The default constructor */ \xOYa
public Page(){ 4EeVO5
aa]|
} /"!ck2d&1
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/** construct the page by everyPage M$v\7vBgO!
* @param everyPage Ai%Wt-
* */ !
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public Page(int everyPage){ H5vg s2R
this.everyPage = everyPage; *` -
} q%s<y+
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/** The whole constructor */ `j2|aX
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public Page(boolean hasPrePage, boolean hasNextPage, `,FA3boE
(<`>B
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int everyPage, int totalPage, )fuAdG
int currentPage, int beginIndex){ }uD*\.
this.hasPrePage = hasPrePage; ZDK+>^A)
this.hasNextPage = hasNextPage; FKtCUq,:
this.everyPage = everyPage; CW@EQ3y0
this.totalPage = totalPage; ;[C_ho
this.currentPage = currentPage; yqb$,$
this.beginIndex = beginIndex; c]ll89`||
} gW G>}M@
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/** x;JC{d#
* @return x'i~o'
* Returns the beginIndex. aE]RVyG@L
*/ t:'^pYN:g
publicint getBeginIndex(){ HlxgJw~<
return beginIndex; lE bV)&'
} tTq2AR|
+s+E!= s
/** d<_IC7$u>
* @param beginIndex F6{Q1DqI
* The beginIndex to set. 93)1
*/ >U:.5Tch'V
publicvoid setBeginIndex(int beginIndex){ bT:;^eG"
this.beginIndex = beginIndex; c~Y g(
} KWVl7Kw#e
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/** K?S5C8
* @return /u'V>=D;f
* Returns the currentPage. {f6~Vwf
*/ gE&83i"
publicint getCurrentPage(){ 1A7(s0J8 :
return currentPage; !&G&
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} %Bn n\{Az
0#sf,ja>
/** bhjJH,%_>
* @param currentPage r*Z p-}
* The currentPage to set. x50ZwV&j
*/ +o6"Z)
publicvoid setCurrentPage(int currentPage){ I&&[ ':
this.currentPage = currentPage; |3EKK:RE
} uw&p)
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/** C%P"\>5@
* @return x*_'uP oS
* Returns the everyPage. &K"qnng/y
*/ lt C
publicint getEveryPage(){ >{h/4T@
return everyPage; >
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} a[BIY&/Q
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/** %vWh1-
* @param everyPage #"JtH"pF
* The everyPage to set. !y;xt?
*/ vcp[$-$QGJ
publicvoid setEveryPage(int everyPage){ G$iC@,/
this.everyPage = everyPage; V(!-xu1,
} /pgn?e'lk
yMe;
/**
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* @return ,h9N,bIQg
* Returns the hasNextPage. )O6_9f_
*/ eBlB0P
publicboolean getHasNextPage(){ LyT[
return hasNextPage; Q[% +y.
} J+nUxF;EE
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/** /80RO:'7
* @param hasNextPage ,6T3:qkkvF
* The hasNextPage to set. VL@eR9}9K
*/ X_J(P?
publicvoid setHasNextPage(boolean hasNextPage){ $-BM`Zt0;
this.hasNextPage = hasNextPage; [G}l;
} k%sh;1.
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/** ujoJ6UOG
* @return F@@6D0\X?
* Returns the hasPrePage. @O&; %IZMY
*/ G+W0X
publicboolean getHasPrePage(){ "D/\&1.&
return hasPrePage; sxn^1|O;m
} qa)Qf,`
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e/\
/** l 1Ns~
* @param hasPrePage !Im{-t
* The hasPrePage to set. Ub*O*nre
*/ CW;=q[+w
publicvoid setHasPrePage(boolean hasPrePage){ hT$/ B|
this.hasPrePage = hasPrePage; CoQ<Ky}*
} .hytn`+9
b#{[Pk,w9
/** ]@mV9:n{
* @return Returns the totalPage. #BwkbOgr
* eQ eucmQd{
*/ aiwKkf`\
publicint getTotalPage(){ J4^aD;j
return totalPage; ]w9\q*S]
} 8al%F_r]
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/** q5ja \
* @param totalPage QMWDII&t
* The totalPage to set. 4A~1Z,"%v(
*/ DH{^9HK
publicvoid setTotalPage(int totalPage){ ycSC'R
this.totalPage = totalPage; g/e2t=qP
} |$.`4h?
tFYod#
} Kv>P+I'|r
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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 Ny)N
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个PageUtil,负责对Page对象进行构造: G[z4 $0f
java代码: nEboet-#D0
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/*Created on 2005-4-14*/ OykYXFv*
package org.flyware.util.page; ^+'\
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import org.apache.commons.logging.Log; ,5HC&@
import org.apache.commons.logging.LogFactory; 1wM~),B8
E)utrO R
/** a+ lGN
* @author Joa _h8|shyP
* ]Geg;[t
*/ @Xj6h!"R
publicclass PageUtil { ;dE'# Kb
;ax%H @o
privatestaticfinal Log logger = LogFactory.getLog z)U/bjf
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(PageUtil.class); wDz}32wB
! 4{T<s;q
/** ftwn<B
* Use the origin page to create a new page ,f?+QV\T.
* @param page f{eMh47 NC
* @param totalRecords U
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* @return k86j&
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*/ 55#s/`gd)^
publicstatic Page createPage(Page page, int B~t[Gy
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totalRecords){ lzup! `g
return createPage(page.getEveryPage(), &'d3Yt
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page.getCurrentPage(), totalRecords); E-J<%+
} pu?D^h9/
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/** '\I!RAZ
* the basic page utils not including exception urA
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handler &R;Cm]jt
* @param everyPage j$jgEtPK9=
* @param currentPage (nLT8{>0
* @param totalRecords `M.\ D
* @return page t,vj)|:
*/ Y+0HC2(o
publicstatic Page createPage(int everyPage, int <9jN4hV
1xzOD@=dI
currentPage, int totalRecords){ n/jZi54gO
everyPage = getEveryPage(everyPage); yITL;dBy
currentPage = getCurrentPage(currentPage); U9eb&nd
int beginIndex = getBeginIndex(everyPage, aokV'6
&yN/AY`U
currentPage); HH3Ln+AWg_
int totalPage = getTotalPage(everyPage, 7ajkp+E6
WG=~GDS>
totalRecords); Vp
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boolean hasNextPage = hasNextPage(currentPage, A4`3yy{0-
z)&ZoSXWc
totalPage); ^7>k:|7-t
boolean hasPrePage = hasPrePage(currentPage); IMtfi(Y%F
"D1u2>(
returnnew Page(hasPrePage, hasNextPage, i]M:ntB"
everyPage, totalPage, *
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currentPage, 99tKs
na,i(m?l
beginIndex); 1]% ]"JbV
} (Ceq@eAlT
rVF7!|&
privatestaticint getEveryPage(int everyPage){ %kSpMj|
return everyPage == 0 ? 10 : everyPage; ipdGAG
} C|hD^m
L92vb zP
privatestaticint getCurrentPage(int currentPage){ D3xyJ
return currentPage == 0 ? 1 : currentPage; Q@w=Jt<
} Tj
v)jD
]mSkjKw
privatestaticint getBeginIndex(int everyPage, int b]cnTR2E
Z/~7N9?m(
currentPage){ cH>3|B*y
return(currentPage - 1) * everyPage; YR/%0^M'0
} 6h%_\I.Z[[
/_.1f|{B
privatestaticint getTotalPage(int everyPage, int ?f'iS#XL
mX&!/U
totalRecords){
I("lGY
int totalPage = 0; g;To}0H
q@0g KC&U
if(totalRecords % everyPage == 0) (>a8h~Na
totalPage = totalRecords / everyPage; FQW{c3%qZ
else *p Q'w
totalPage = totalRecords / everyPage + 1 ; Vnvfu!>(
yirQ
return totalPage; 9w:9XziT
} bj$VYS"kY
1Q>D^yPI[
privatestaticboolean hasPrePage(int currentPage){ Y `ySNC
return currentPage == 1 ? false : true; E@%9u#
} Tw+V$:$$
tX@G`Mr(
privatestaticboolean hasNextPage(int currentPage, R7Z7o4jg
"B3&v%b
int totalPage){ \~~y1.,U.
return currentPage == totalPage || totalPage == sm9/sX!
+fRABY5C
0 ? false : true; Wi%e9r{hU
} rS&"UH?c7
`m7w%J.> n
|(77ao3
} Iq["(!7E5
SL ) ope
i4s_:%+
eb#p-=^KP
yh:Wg$qx
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 SQ0?M\D7
}K'gjs/N;
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 A8oTcX_
o<Y[GW1pg
做法如下: :HW\awv
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 PPMAj@B}V
Wkj0z]]?
的信息,和一个结果集List: x?rn<=
java代码: 3<R8_p
lGZf_X)gA^
V(c>1xLlz
/*Created on 2005-6-13*/ 4Mck/i2
package com.adt.bo; t$zeBOI)
c%x9.s<+1
import java.util.List; 1];OGJuJ2
/(jG9RM
import org.flyware.util.page.Page; 6i`Y]\X~#
>Sc/E}3
/** tQ7:4._
* @author Joa )~2~q7
*/ tB)nQw7
publicclass Result { Xdl7'~k
?4%@"49n X
private Page page; ]TX"BH"2
3)0z( 30
private List content; wS+ekt5
pgipT#_K
/** ?(R!BB
* The default constructor A!uO7".E
*/ VqL#w<A%
public Result(){ "J"RH:$v
super(); H9%[!
RF
} cf+EQY
P1qQ)-J
/** aGbHDo
* The constructor using fields !))!!{
* Ls6C*<8
* @param page ;>*Pwz`~jT
* @param content ,Z$!:U
*/ Y5z5LG4
public Result(Page page, List content){ /mG-g%gE
this.page = page; u?7^+z
this.content = content; G<M9 6V
} u8r<B4k
F_.1^XM
/** des.TSZ
* @return Returns the content. 9!?Ywc>0#
*/ 7xh91EU:4
publicList getContent(){ U%r|hn3
return content; \]|(w*C
} 0`KR8# A@
)o`[wq
/** ~i
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* @return Returns the page. UZRN4tru6
*/ z2~\
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public Page getPage(){ ?<efKs
return page; -Dy":/Bk
} +F]=Z
>qS2ha
/** Plj >+XRO
* @param content )<(3 .M
* The content to set. p)Fi{%bc
*/ 'y&DOy/|
public void setContent(List content){ ~c`%k>$
this.content = content; eZ8DW6 l*
} ^TEFKx}PX
szUJh9-
/** * -X`^R
* @param page ;pt.)5
* The page to set. hV}C.- 6h
*/ zK>}x=
publicvoid setPage(Page page){ h@CP
this.page = page; aIo%~w
} +FH@|~^O
} V='A;gs
#`@5`;U>#
ov\+&=IRG
]ONBr(M\
F60?%gg
2. 编写业务逻辑接口,并实现它(UserManager, C;0VR
kgP6'`}E[
UserManagerImpl) Y?AvcY.
java代码: \ 0/m$V.
3?Fe(!@
-unQ4G
/*Created on 2005-7-15*/ %m##i
package com.adt.service; $6]1T>
_0o65?F
import net.sf.hibernate.HibernateException;
[L=M=;{4
@k9n 0Qe|F
import org.flyware.util.page.Page; z:oi@q
n{(,r'
import com.adt.bo.Result; ^G14Z5.
<9]J/w+
/** R>hL.+l.
* @author Joa ^B$cfs@*
*/ &2r[4
publicinterface UserManager { 2oo\ SmO]
J\hqK*/8
public Result listUser(Page page)throws Ze?n Q-
?{%"v\w
HibernateException; 'HJ<"<
0IyT(1hS
} 3QCCX$,
qNWSDZQ
y#FFxSH>
%-<6Z9otc
rP IAu[],g
java代码: Kf# iF*
xy-Vw"I[bh
Q%W>m0%
/*Created on 2005-7-15*/ ]F3fO5Z
package com.adt.service.impl; %awr3h>$
5[]Yx l
import java.util.List; 5!BW!-q
l[^0Ik-G
import net.sf.hibernate.HibernateException; Q_`EKz;N{
:}CcWfbT
import org.flyware.util.page.Page; T%aM~dp
import org.flyware.util.page.PageUtil; [e o=
UAGh2?q2
import com.adt.bo.Result; gOr%N!5
import com.adt.dao.UserDAO; M7{_"9X{
import com.adt.exception.ObjectNotFoundException; 8On MtP
import com.adt.service.UserManager; ?8FJMFv;4%
fo~>y
/** '4}8WYKQ
* @author Joa +1^L35\@
*/ y?Pw6;e.
publicclass UserManagerImpl implements UserManager { {a]u
O7m-_#/\
private UserDAO userDAO; EFv^uve
y"k%Wa`*
/** yIg^iZD
* @param userDAO The userDAO to set. G +AP."M?
*/ 4m6/ba
publicvoid setUserDAO(UserDAO userDAO){ =s9*=5r 8
this.userDAO = userDAO; sF3@7~m4
} e.W <pI,
,[<$X{9
/* (non-Javadoc) thz[h5C?C
* @see com.adt.service.UserManager#listUser Zr(eH2}0D
eQ*zi9na
(org.flyware.util.page.Page) gHFQs](G.
*/ 3R%yKa#
public Result listUser(Page page)throws i:Gyi([C
~=9S AJr]
HibernateException, ObjectNotFoundException { Qe_C^(P
int totalRecords = userDAO.getUserCount(); rONz*ly|i
if(totalRecords == 0) WLiF D.
throw new ObjectNotFoundException N*+WGsxl$z
|Xt6`~iC
("userNotExist"); _na/&J6
page = PageUtil.createPage(page, totalRecords); |l@z7R+4*
List users = userDAO.getUserByPage(page); WM7LCP
returnnew Result(page, users); *JAC+<~d
} ^oR
qu
4'td6F
} &Zjs
'K\H$<CJ
g_rk_4]
(\nEU! Y
OIkjO}/7
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 K"ly\$F
@>&b&uj7T
询,接下来编写UserDAO的代码: x~F YG
3. UserDAO 和 UserDAOImpl: 7a=ul:
java代码: O:ACp<@
"{kE#`c6<n
"{Hl! Zq/
/*Created on 2005-7-15*/ pu_?)U
package com.adt.dao; ]x(6^:D5
Dl,sl>{
import java.util.List; Sjo-Xf}
lMcO2006L
import org.flyware.util.page.Page; +S'm<}"1
8_pyfb
import net.sf.hibernate.HibernateException; nJ$2RN
TpI8mDO\W
/** FL4BdJ\
* @author Joa '6\ZgOO9
*/ p+0gE5
publicinterface UserDAO extends BaseDAO { vy`
lfbX@
"H=N>=g0E
publicList getUserByName(String name)throws ^XG$?2<U
E!uQ>'iq.
HibernateException; D&i,`j
U.h2 (-p
publicint getUserCount()throws HibernateException; =uEpeL~d;+
2vhP'?;K
publicList getUserByPage(Page page)throws HD3WsIim*
Z!*6;[]SfG
HibernateException; ~NLthZ(O
?zfm"o
} y:_>R=sw
%gj7KF
[WV&Y,E
aX*9T8H/
@pH6FXVGzt
java代码: ]z#)XW3#i
=)Fb&h]G^
5z\,]
/*Created on 2005-7-15*/ F_I!qcEQ
package com.adt.dao.impl; \<dg
"zkQu
import java.util.List; YV} "#
r4<As` &
import org.flyware.util.page.Page; M8$eMS1
4*IXBi7%
import net.sf.hibernate.HibernateException; h<bhH=6~
import net.sf.hibernate.Query; ~gHn>]S0
P 00%EB
import com.adt.dao.UserDAO; Z9|A"[b
s0:M'wA
/** 9JX@ck
* @author Joa {:3:GdM6
*/ %3AE2"
public class UserDAOImpl extends BaseDAOHibernateImpl pvb&vtp
l<+PA$+}}
implements UserDAO { %nG>3.%
^Wn+G8n
/* (non-Javadoc) jatlv/,
* @see com.adt.dao.UserDAO#getUserByName )y i~p
LbYIRX
(java.lang.String) [9V}>kS)
*/ B#+n$5#FK
publicList getUserByName(String name)throws z30 mk
EUVD)+it
HibernateException { :U/]*0b
String querySentence = "FROM user in class #Ma:Av/
)
!0P:G#o-$
com.adt.po.User WHERE user.name=:name"; w%..*+P
Query query = getSession().createQuery JYmYX-
'.<c[Mp
(querySentence); cd=|P?Bi
query.setParameter("name", name); g'{?j~g
return query.list(); Ryh 0r
} (:O6sTx-hE
<&g