Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 W0qR?jc
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 y>I2}P
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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 2Ez<Iw
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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 #[+# bw_6
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分页支持类: 3JnpI,By
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java代码: bJ~H
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package com.javaeye.common.util; sPH2KwEv
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import java.util.List; F-&tSU,
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publicclass PaginationSupport { u#0snw~)/
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publicfinalstaticint PAGESIZE = 30; V;M_Y$`Lh
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privateint pageSize = PAGESIZE; O'<V[Y}6
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privateList items; A_xC@$1e<
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privateint totalCount; 'p@f5[t
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privateint[] indexes = newint[0]; c_J9CKqc
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privateint startIndex = 0; 0=Z[6Q@:
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public PaginationSupport(List items, int >!963>D R
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totalCount){
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setPageSize(PAGESIZE); *dl hRa
setTotalCount(totalCount); Fr9/TI
setItems(items); w,UE0i9I
setStartIndex(0); J4Gzp~{
} *uvM6F$ut
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public PaginationSupport(List items, int bi<<z-q`wJ
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totalCount, int startIndex){ {,>G 1>Yv
setPageSize(PAGESIZE); 6u[fCGi%
setTotalCount(totalCount); 3I6ocj[,
setItems(items); $7x2TiAL
setStartIndex(startIndex); s8h*nZ)v
} +QChD*
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public PaginationSupport(List items, int F/5&:e?( )
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totalCount, int pageSize, int startIndex){ _$~>O7
setPageSize(pageSize); 8mI(0m'
setTotalCount(totalCount); 0At0`Q#
setItems(items); @8d 3
setStartIndex(startIndex); c6h?b[]
} inut'@=G/
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publicList getItems(){ KC/O
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return items; {6i|"5_j
} #;[G>-tC
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publicvoid setItems(List items){ oC0ndp~+&
this.items = items; 56V|=MzX]
} ;mQj2Bwr
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publicint getPageSize(){ fBS a8D3}`
return pageSize; at uqo3
} 4~fYG| a
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publicvoid setPageSize(int pageSize){ n`Q@<op
this.pageSize = pageSize; K;F1'5+=D
} .. `I<2
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publicint getTotalCount(){ SUS=sR/N
return totalCount; Z#[?~P
} D|uvgu2
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publicvoid setTotalCount(int totalCount){ c_8&4
if(totalCount > 0){ <WXVUEea
this.totalCount = totalCount; e~)[I! n
int count = totalCount / 3>O|i2U
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pageSize; F*72g)hVh
if(totalCount % pageSize > 0) ww2mL
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count++; ztp|FUi
indexes = newint[count]; e@D_0OZ
for(int i = 0; i < count; i++){ '|8dt "C
indexes = pageSize * <jh4P!\&j
: auR0FE
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} ;[ <(4v$
}else{ = oAS(7o
this.totalCount = 0; `YhGd?uu$
} T#!>mL|9|
} A3]A5s6
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publicint[] getIndexes(){ Xu$>$D#a
return indexes; b:==:d:0s
} z.Cj%N
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publicvoid setIndexes(int[] indexes){ PK|-2R"M
this.indexes = indexes; kx,.)qKk
} =p5DT
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publicint getStartIndex(){ mxNd_{n
return startIndex; K%q5:9m
} `/O`%6,f1!
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publicvoid setStartIndex(int startIndex){ QLqtE;;)JK
if(totalCount <= 0) S<Dbv?
this.startIndex = 0; ;V,L_"/X
elseif(startIndex >= totalCount) eL3 _Lz
this.startIndex = indexes zxR]+9Zh
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[indexes.length - 1]; ;aQ``B
elseif(startIndex < 0) _ *f>UW*,
this.startIndex = 0; omE- c
else{ KC;cu%H
this.startIndex = indexes I&-r^6Yx
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[startIndex / pageSize]; 3^8Cc(bk
} 4]o+)d.`(
} Y'U1=w~E
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publicint getNextIndex(){ D<WnPLA$g
int nextIndex = getStartIndex() + :[0 R F^2}
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pageSize; F0$w9p
if(nextIndex >= totalCount) M(X
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return getStartIndex(); wQ33Gc
else ] Q5:JV
return nextIndex; .psb#4
} ,`geOJn'
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publicint getPreviousIndex(){ ;Y7'U rn
int previousIndex = getStartIndex() - #Y7jNrxE
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pageSize; V}y]<
if(previousIndex < 0) sT^R0Q'>
return0; MK1\
else J[ZHAnmPH
return previousIndex; :nx+(xgw
} L
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} ~$J;yo~
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抽象业务类 $Q*R/MY
java代码: ,rMf;/[
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/** ,,Qg"C
* Created on 2005-7-12 s= %3`3Fo
*/ #^}H)>jWy
package com.javaeye.common.business; oU\]#e^
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import java.io.Serializable; xfRp_;l+R
import java.util.List; C19N0=
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import org.hibernate.Criteria; wgFX')l:
import org.hibernate.HibernateException;
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import org.hibernate.Session; )7 57
import org.hibernate.criterion.DetachedCriteria; j_<qnBeQ
import org.hibernate.criterion.Projections; DTO_IP
import |=0vgwd"S
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org.springframework.orm.hibernate3.HibernateCallback; ]0UYxv%]
import IxbQ6
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org.springframework.orm.hibernate3.support.HibernateDaoS $;^|]/-
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upport; s#^0[ Rt
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import com.javaeye.common.util.PaginationSupport; i-|N6J
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public abstract class AbstractManager extends z~t0l
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HibernateDaoSupport { z/\OtYz
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privateboolean cacheQueries = false; /43l}6I
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privateString queryCacheRegion; Ph^1Ko"2
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publicvoid setCacheQueries(boolean $gr>Y2i
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cacheQueries){ ,C,nNaW
this.cacheQueries = cacheQueries; NK0'\~7&
} 7r;16"
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publicvoid setQueryCacheRegion(String 'V]C.`9c
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queryCacheRegion){ {Z2nc)|7C
this.queryCacheRegion = k'8tcXs
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queryCacheRegion; 8UU
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} +jhzE%
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publicvoid save(finalObject entity){ 9J/[7TzSZ
getHibernateTemplate().save(entity); YE`Y t
} 7qqzL_d>
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publicvoid persist(finalObject entity){ Y%;J/4dd
getHibernateTemplate().save(entity); .Y6v#VI
} S<7!<]F-
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publicvoid update(finalObject entity){ [xiqlb,8
getHibernateTemplate().update(entity); ,#2~<
} 3)WfBvG
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publicvoid delete(finalObject entity){ S%- kN;
getHibernateTemplate().delete(entity); xX-r<:'tmi
}
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publicObject load(finalClass entity, /B t!xSI
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finalSerializable id){ !7DDPJ~
return getHibernateTemplate().load CHGa_
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(entity, id); p3vf7 eqn
} W5Jw^,iPd
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publicObject get(finalClass entity, x+cL(R
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finalSerializable id){ j""ZFh04
return getHibernateTemplate().get $
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(entity, id); m ""+$
} x=cucZ
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publicList findAll(finalClass entity){ ]In7%Qb
return getHibernateTemplate().find("from V8/4:Va7s
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" + entity.getName()); z%
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} jJIP $
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publicList findByNamedQuery(finalString v,iZnANZ&P
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namedQuery){ S]fu
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return getHibernateTemplate 5,
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().findByNamedQuery(namedQuery); JlYZ\
} Q0(6n8i
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publicList findByNamedQuery(finalString query, Po58@g
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finalObject parameter){ 6FzB-],
return getHibernateTemplate nG<oae6z"
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().findByNamedQuery(query, parameter); SOI=~BGd)
} ?Kgb-bXB
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publicList findByNamedQuery(finalString query, u@dvFzc
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finalObject[] parameters){ 'S3<' X
return getHibernateTemplate 0g[ %)C
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().findByNamedQuery(query, parameters); y@!M<#SEzG
} jRjeL'"G
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publicList find(finalString query){ >OaD7
return getHibernateTemplate().find d@ K-ZMq
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(query); 5TJd9:\Af
} bY#BK_8 :
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publicList find(finalString query, finalObject MS\vrq'_
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parameter){ 4`i8m
return getHibernateTemplate().find 41<~_+-@
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(query, parameter); +vy fhw4
} FGi7KV=N
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public PaginationSupport findPageByCriteria Rq}lW.<r
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(final DetachedCriteria detachedCriteria){ XHU$&t`7>g
return findPageByCriteria vu0Ue
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); <-k!
} C7S\4rDJ
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public PaginationSupport findPageByCriteria '?Dxe
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(final DetachedCriteria detachedCriteria, finalint f(pq`v^-n
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startIndex){ #VrIU8Q7'
return findPageByCriteria l^	d
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(detachedCriteria, PaginationSupport.PAGESIZE, t}eyfflZ
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startIndex); K ~mUO
} aG]>{(~cL
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public PaginationSupport findPageByCriteria rD=D.1_
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(final DetachedCriteria detachedCriteria, finalint +7b8 ye
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pageSize, Mq$K[]F
finalint startIndex){ ULAr!
return(PaginationSupport) jn5xYKv
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getHibernateTemplate().execute(new HibernateCallback(){ U|3!ixk>>w
publicObject doInHibernate Nhs!_-_I
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(Session session)throws HibernateException { C=+9XfP 0
Criteria criteria = ]zlA<w8
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detachedCriteria.getExecutableCriteria(session); ^;_~mq.
int totalCount = ~snj92K
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((Integer) criteria.setProjection(Projections.rowCount 0<%$lr
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()).uniqueResult()).intValue(); ^0.8-RT
criteria.setProjection 7Jlkn=9e:
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(null); F_*']:p
List items = W q<t+E[
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criteria.setFirstResult(startIndex).setMaxResults Iuxf`sd
CI{2(.n4
(pageSize).list(); -!XG>Z
PaginationSupport ps = ]B3](TH"
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new PaginationSupport(items, totalCount, pageSize, <(KCiM=E$
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startIndex); wGti|7Tu*
return ps; vntJe^IaFd
} &DMC\R* j
}, true); S=k!8]/d|
} Y$L`
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public List findAllByCriteria(final (%fQhQ
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DetachedCriteria detachedCriteria){ {\(G^B*\
return(List) getHibernateTemplate C*2%Ix18+N
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().execute(new HibernateCallback(){ !Axe}RD'
publicObject doInHibernate !}!KT(%%
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(Session session)throws HibernateException { D
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Criteria criteria = i%9vZ
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detachedCriteria.getExecutableCriteria(session); \( s `=(t
return criteria.list(); Y_Gd_+oJ
} WkuCnT
}, true); jOV6%
} @SD XJJh
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public int getCountByCriteria(final 1)=
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DetachedCriteria detachedCriteria){ iW6O9~
Integer count = (Integer) B!Wp=9)G
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getHibernateTemplate().execute(new HibernateCallback(){ r^
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publicObject doInHibernate sg,\!'
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(Session session)throws HibernateException { ,w~3K%B4
Criteria criteria = 50MM05aC
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detachedCriteria.getExecutableCriteria(session); rT `sY
return xq;>||B
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criteria.setProjection(Projections.rowCount FXr^ 4B}
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()).uniqueResult(); 9Vm
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} L~5f*LE$1
}, true); 3g;Y
return count.intValue(); pl>b 6 |
} {O>Td9
} 7SHllZ
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用户在web层构造查询条件detachedCriteria,和可选的 us.[wp'Sh
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @S3 L%lOH
) 'xyK
PaginationSupport的实例ps。 *R+M#l9D`
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ps.getItems()得到已分页好的结果集 -dovk?'Gj
ps.getIndexes()得到分页索引的数组 y7pBcyWTE=
ps.getTotalCount()得到总结果数 gqv+|:#
ps.getStartIndex()当前分页索引 IER;d\_V<
ps.getNextIndex()下一页索引 ;cVK2'
ps.getPreviousIndex()上一页索引 RP2$(%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 e r_6PV
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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 }m<+tn3m
sFZdj0tQ4
一下代码重构了。 p8 S~`fjV
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我把原本我的做法也提供出来供大家讨论吧: Dl.<(/
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首先,为了实现分页查询,我封装了一个Page类: /HUT6B
java代码: 2(!W
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/*Created on 2005-4-14*/ %S^ke`MhF
package org.flyware.util.page; EJ
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/** U`)
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* @author Joa s>L-0vG
* d1#lC*.Sg
*/ cWnEp';.
publicclass Page { y3(~8n
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/** imply if the page has previous page */ "zw{m+7f,
privateboolean hasPrePage; ]iTP5~8U
O)^F z:
/** imply if the page has next page */ kR1
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privateboolean hasNextPage; ]foS.D,
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/** the number of every page */ c
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privateint everyPage; )PR`irw
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/** the total page number */ yUcU-pQ
privateint totalPage;
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/** the number of current page */ uLv
privateint currentPage; .&5 3sJ0{
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/** the begin index of the records by the current %l%ad-V
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query */ sz%]rN6$
privateint beginIndex; }qGd*k0F0
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/** The default constructor */ xX%{i0E
public Page(){ [2Y@O7;nI
@sa_/LH!K
} TyO]|Q5
y z3=#
/** construct the page by everyPage ^VzhjKSu
* @param everyPage w?_'sP{pd
* */ fvta<
public Page(int everyPage){ }x6)}sz7
this.everyPage = everyPage; "w 4^i!\
} LTx,oa:ma
@}^VA9ULK
/** The whole constructor */ ~2[kCuu
public Page(boolean hasPrePage, boolean hasNextPage, T
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int everyPage, int totalPage, GS>YfJ&DZ
int currentPage, int beginIndex){ .5SYN-@
this.hasPrePage = hasPrePage; @(6P L^I
this.hasNextPage = hasNextPage; iqoMQ7%
this.everyPage = everyPage; v"Bm4+c&0
this.totalPage = totalPage; gr!!pp;
this.currentPage = currentPage; uu-M7>+
this.beginIndex = beginIndex; 0WZd $
} ^[I>#U
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/** 1.,KN:qe
* @return \0i0#Dt9
* Returns the beginIndex. ;fQIaE&H
*/ "\lOOp^-
publicint getBeginIndex(){ *k&V;?x|wt
return beginIndex; 6[FXgCb
} Lf.Ia*R:
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/** s{c|J#s
* @param beginIndex %IIFLlD
* The beginIndex to set. iig4JP'h
*/ x*j
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publicvoid setBeginIndex(int beginIndex){ c8zok `\P_
this.beginIndex = beginIndex; `"V}Wq ?I
} -j Nnx*
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/** _b)Ie`a.H
* @return |A|K);
* Returns the currentPage. Y HgNL LZ?
*/ u!HbS*jqq
publicint getCurrentPage(){ Ke[`zui@?
return currentPage; h0x'QiCc
} Jz0AYiCq
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/** 3k8nWT:wT
* @param currentPage <h|&7
* The currentPage to set. %"#ydOy
*/ Y#P!<Q>}
publicvoid setCurrentPage(int currentPage){ P=P']\`p+
this.currentPage = currentPage; =~,2E;#X
} ES(qu]CjI
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/** Wj)v,v2&
* @return (bpxj3@R
* Returns the everyPage. 19[.&-u"
*/ JS?%zj&@
publicint getEveryPage(){ C!1)3w|
return everyPage; 5|}u25J
} +~==qLsU
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/** =pj3G?F#
* @param everyPage zII^Ny8D
* The everyPage to set. rNm_w>bq
*/ ;S&anC#E
publicvoid setEveryPage(int everyPage){ 2H] 7 =j
this.everyPage = everyPage; FUL'=Xo
} ^P.U_2&
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/** 1(i%nX<U
* @return *6}'bdQbNP
* Returns the hasNextPage. fG8^ |:
*/ S s+
publicboolean getHasNextPage(){ t,A=B(W
return hasNextPage; g^#,!e
} J_<6;#
X_3hh} =
/** oZL# *Z(h
* @param hasNextPage l%u8Lq
* The hasNextPage to set. cUw$F{|W
*/ )RWY("SUy1
publicvoid setHasNextPage(boolean hasNextPage){ %Yg|QBm|
this.hasNextPage = hasNextPage; Y!ypG-
} 2PNe~9)*#
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/** y\:Ma7V
* @return ^FTS'/Q
* Returns the hasPrePage. >C5u>@%9O
*/ k|jr+hmn":
publicboolean getHasPrePage(){ tQ.H/;
return hasPrePage; kf95 )iLo
} ExFz@6@
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/** T;,,!
* @param hasPrePage c:B` <
* The hasPrePage to set. I,Jb_)H&t
*/ r0pwKRE~t
publicvoid setHasPrePage(boolean hasPrePage){ 0hXx31JN N
this.hasPrePage = hasPrePage; >I;.q|T
} SC3_S.
d<m.5ECC}
/** yKz%-6cpSl
* @return Returns the totalPage. YPKB4p#
* <1QXZfQ"
*/ ,nV4%Aa
publicint getTotalPage(){ G2sj<F=AV
return totalPage; z$ {[Z=
} Le/}xST@
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/** \zDs3Hp
* @param totalPage 5Z:qU{[
* The totalPage to set. _ib
@<%
*/ AW!A+?F6
publicvoid setTotalPage(int totalPage){ iG=Di)O
this.totalPage = totalPage; }{&;\^i
} CHCT
e
[;~"ctf{
} <33,0."K
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/*M3Ns1@2
E},zB*5TH
]9W7]$
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 5e?<x>e
tCwB7c-
个PageUtil,负责对Page对象进行构造: 7y.iXe!P
java代码: ao|n<*}
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Nz;\PS
/*Created on 2005-4-14*/ z"Cyjmg"
package org.flyware.util.page; O{U j
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Ut
import org.apache.commons.logging.Log; @a
7U0$,O#
import org.apache.commons.logging.LogFactory; Y|tK19
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/** {&6i$4T
* @author Joa pEW~zl
* NQvI=R-g
*/ DhsvN&yNM
publicclass PageUtil { )ac!@slb^7
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privatestaticfinal Log logger = LogFactory.getLog |TR
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@:>gRD
(PageUtil.class); ~zWLqnS}
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/** MGre_=Dm_
* Use the origin page to create a new page uW!saT5o
* @param page #k)t.P
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* @param totalRecords k;qWiYMV
* @return 3 4&xh1=3
*/ ~sq@^<M)s
publicstatic Page createPage(Page page, int ?a1pO#{Dg
6)20%*[
totalRecords){ +m/n~-6q
return createPage(page.getEveryPage(), 7QoMroR
\F""G,AWq{
page.getCurrentPage(), totalRecords); U;!J(Us
} R-wz+j#
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/** !?+q7U
* the basic page utils not including exception k*Aee7
lWT`y
handler G!h75G20
* @param everyPage l/\D0\x2
* @param currentPage AD@ {7
* @param totalRecords g=,}j]tl
* @return page TNK1E
*/ 3=*ur( Qy
publicstatic Page createPage(int everyPage, int N0JdU4'
`46.!
currentPage, int totalRecords){ GJs~aRiz
everyPage = getEveryPage(everyPage); (vvD<S*
currentPage = getCurrentPage(currentPage); @X560_x[q
int beginIndex = getBeginIndex(everyPage, ;P/ 4.|<
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currentPage); 9jM7z/Ff
int totalPage = getTotalPage(everyPage, @7V~CNB+
>VX'`5r>uw
totalRecords); n+i=Ff
boolean hasNextPage = hasNextPage(currentPage, KD H<T4#x
:F@goiuC
totalPage); A
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boolean hasPrePage = hasPrePage(currentPage); =q`T|9v
Gzg3{fXl
returnnew Page(hasPrePage, hasNextPage, !ab ef.%:
everyPage, totalPage, )}t't"
currentPage, L'
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beginIndex); Zj1bG{G=i
} 5Z6MQ`(k
YhqMTOw
privatestaticint getEveryPage(int everyPage){ gx?r8
return everyPage == 0 ? 10 : everyPage; NK(_ &.F
} M CP GDr
y\Utm$)j
privatestaticint getCurrentPage(int currentPage){ ()F{kM8
return currentPage == 0 ? 1 : currentPage; 1xkrhqq
} ZmNNR 1%/
p(8 @
privatestaticint getBeginIndex(int everyPage, int *c&|2EsZ
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currentPage){ 2A:h&t/|C
return(currentPage - 1) * everyPage; \xv(&94U
} G.v(2~QFd
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privatestaticint getTotalPage(int everyPage, int
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aql8Or1[
totalRecords){ Y:, rN
int totalPage = 0; <gfRAeXA
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if(totalRecords % everyPage == 0) A^A)arJS
totalPage = totalRecords / everyPage; N;6o=^ic
else Pz\K3-
totalPage = totalRecords / everyPage + 1 ; $CX3P)%
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return totalPage; !\9^|Ef?
} P=\{
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privatestaticboolean hasPrePage(int currentPage){ 4v3gpLH
return currentPage == 1 ? false : true; ;ko6igx)+
} )5gj0#|CG@
7')W+`o8eL
privatestaticboolean hasNextPage(int currentPage, ,]W|"NUI
8N?D1;F;
int totalPage){ ' VKD$q
return currentPage == totalPage || totalPage == :."oWqb)
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0 ? false : true; />/e
} wJCw6&D,/
( N};.DB1Y
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} '%XYJr:H[
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N' R^gL
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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。 n-yUt72
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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 19#>\9*
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做法如下: 0<NS1y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 4OpzGZ4+
*X2PT(e[
的信息,和一个结果集List: %A=/(%T>
java代码: #
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c@3 5\!9
/*Created on 2005-6-13*/ oW6Hufu+o
package com.adt.bo; b/]4#?g
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import java.util.List; 3?I!
31a lQ\TH
import org.flyware.util.page.Page; bvB',yBZ
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/** z+{qQ!
* @author Joa ,f$P[c
*/ k:R\;l5
publicclass Result { ] \_tO
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private Page page; H@?} !@
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private List content; _#6Qf
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/** ,)#rD9ZnC
* The default constructor )`f-qTe
*/ ~ILv*v@m
public Result(){ e'G=.:
super(); NimgU Fa
} 9n{Y6I
x:
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/** ;M4[Liw~O
* The constructor using fields ,v>;/qm
* pTwzVz~
* @param page Pd"c*n&9
* @param content <TtPwUX
*/ zdRVAcrwQ
public Result(Page page, List content){ tJrGRlB>
this.page = page; 4=Ru{ewRV
this.content = content; xL"J?Gy
} XxS#~J?:_
%bN{FKNN
/** LkS tU)
* @return Returns the content. vu\W5M
*/ ?%hd3zc+f
publicList getContent(){ ^]R_t@
return content; VPYLDg.'
} *m+FMyr
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/** bHnKtaK4c
* @return Returns the page. <m`CLVx8m
*/ B #%QY\<X
public Page getPage(){ yj4"eDg]
return page; N{HAWB{
} i~]60M>
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/** >*ls}
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* @param content w+
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* The content to set. 1Ys=KA-!_x
*/ yV:8>9wE8
public void setContent(List content){ (l{8Ixs
this.content = content; ;P)oKx
} GEc-<`-
fGlvum
/** v9:J 55x
* @param page 2[+.*Ef
* The page to set. !<:Cd(bM
*/ XKky-LeJ
publicvoid setPage(Page page){ <$z[pw<
this.page = page; #C&';HB;y
} s_NY#MPz[
} X1.-C@o
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2. 编写业务逻辑接口,并实现它(UserManager, #RR;?`,L}
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UserManagerImpl) 4uOR=+/l
java代码: 2{b/*w
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/*Created on 2005-7-15*/ %"mI["{
package com.adt.service; ojnO69v
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import net.sf.hibernate.HibernateException; ]j>xQm\
YFm%W@
import org.flyware.util.page.Page; oqF?9<Vgc,
% akW43cE
import com.adt.bo.Result; GuR^L@+ -.
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/** {TNORbZz
* @author Joa _`?cBu`
*/ (yP1}?
publicinterface UserManager { |hika`35K
aH1CX<3)~
public Result listUser(Page page)throws z)C/U
md+pS"8o;
HibernateException; yor'"6)i
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} QNx]8r
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java代码: &wK:R,~x6
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r
1r@TG\
/*Created on 2005-7-15*/ h^=;\ng1l
package com.adt.service.impl; hE(R[hc
g}<jn'@{
import java.util.List; C`;igg$t_
0(-4"u>?
import net.sf.hibernate.HibernateException; )^o.H~Pv
?m *e$!M0
import org.flyware.util.page.Page; NuR7pjNMZ
import org.flyware.util.page.PageUtil; :38{YCN
d|RUxNjM-J
import com.adt.bo.Result; *xNc^&.
import com.adt.dao.UserDAO; $f3 IO#N
import com.adt.exception.ObjectNotFoundException; <)T| HKx
import com.adt.service.UserManager; ?3BcjD0
o@L0ET
/** ?P0b/g
* @author Joa #b;?:.m\=
*/ zz
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publicclass UserManagerImpl implements UserManager { gP
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private UserDAO userDAO; T)I)r239h
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/** %evb.h)
* @param userDAO The userDAO to set. aNu.4c/5
*/ I^k&v V
publicvoid setUserDAO(UserDAO userDAO){ @)h>vg
this.userDAO = userDAO; 06Wqfzceb
} $4g{4-)
o^2MfFS
/* (non-Javadoc) ZXb|3|D
* @see com.adt.service.UserManager#listUser TbD
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(org.flyware.util.page.Page) N[W#wYbH
*/ 0C :8X
public Result listUser(Page page)throws =|i_T%a
%htI!b+"@
HibernateException, ObjectNotFoundException { 3*</vo#`
int totalRecords = userDAO.getUserCount(); C+**!uYIB
if(totalRecords == 0) ]F+|C
throw new ObjectNotFoundException i,;JI>U
qa^cJ1@
("userNotExist"); Kc\8GkdB
page = PageUtil.createPage(page, totalRecords); nIg 88*6b,
List users = userDAO.getUserByPage(page); +w]#26`d
returnnew Result(page, users); Cik1~5iF
} As46:<!2
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} D{JjSky
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 _$AM=?P&
q{&c?l*2
询,接下来编写UserDAO的代码: oH=?1~e
3. UserDAO 和 UserDAOImpl: ,]1f)>
java代码: .*`^dt
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/*Created on 2005-7-15*/ bss2<mqlH
package com.adt.dao; Xsa8YP9
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import java.util.List; =OFhM7
'/xynk%)xw
import org.flyware.util.page.Page; 4\-11!'08
f\oW<2k]~
import net.sf.hibernate.HibernateException; m:)&:Y0 (a
W|8VE,"7
/** Q8`V0E\~
* @author Joa 7vZO;FGtG
*/ F 6sQeU
publicinterface UserDAO extends BaseDAO { y\_+,G0
FcM)v"bF&]
publicList getUserByName(String name)throws TQck$&
n}a`|Nbk
HibernateException; @Pcgm"H<
!+3&%vQ)
publicint getUserCount()throws HibernateException; U3&GRY|##
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publicList getUserByPage(Page page)throws d\>XfS
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HibernateException; sf2%WPK
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} m
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WOj}+?/3 R
} +Sp7F1q
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java代码: hiVa\s
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]^"Lc~w8&
/*Created on 2005-7-15*/ `l]Lvk8O
package com.adt.dao.impl; 0qNk.1pv
M#4;y,n<k
import java.util.List; w ?_8OJ
w =F9>
import org.flyware.util.page.Page; o;6~pw%
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import net.sf.hibernate.HibernateException; C0f%~UMwd
import net.sf.hibernate.Query; me2vR#
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import com.adt.dao.UserDAO; 4)e1K/PJ)
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/**
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* @author Joa 6Tmz!E0
*/ 9 RDs`>v
public class UserDAOImpl extends BaseDAOHibernateImpl {v'eP[
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