Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 :d=:>_[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @/W~lJ!e
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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 `'G1"CX
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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 $2w][ d1
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分页支持类: ]x5+v0
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java代码: /i)>|U
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package com.javaeye.common.util; XiO~^=J
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import java.util.List; {RC&Ub>
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publicclass PaginationSupport { e+<'=_x {
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publicfinalstaticint PAGESIZE = 30; a.2Xl}2o5
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privateint pageSize = PAGESIZE; Tfp^h~&u
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privateList items; %%sJ+)
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privateint totalCount; F R(k==pZ
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privateint[] indexes = newint[0]; y.$Ae1a=
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privateint startIndex = 0; C7FxV2
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public PaginationSupport(List items, int U:0Ma6<
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totalCount){ NwyNl
setPageSize(PAGESIZE); B \LmE+a>
setTotalCount(totalCount); <q&4Y+b
setItems(items); MdDL?ev
setStartIndex(0); ;EQ7kuJQ?
} X?U'GLm
GfV#^qi
public PaginationSupport(List items, int e'MW"uCP}
A(*c|Aj9
totalCount, int startIndex){ {H*
setPageSize(PAGESIZE); ?I$- im
setTotalCount(totalCount); bTt1y O
setItems(items); t:"3MiM=c
setStartIndex(startIndex); <$u\PJF7_^
} &z#`Qa3NI
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public PaginationSupport(List items, int qKrxln/T
)|/%]@` N
totalCount, int pageSize, int startIndex){ (K_{a+$[
setPageSize(pageSize); oFGWI#]ts>
setTotalCount(totalCount); O-huC:zZh
setItems(items); U C_$5~8p
setStartIndex(startIndex); A*g-pJh
} 2u$rloc$b
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publicList getItems(){ zdm2`D;~p
return items; 1|m%xX,[
} O7p=N8 V
y,/i3^y#_
publicvoid setItems(List items){ VeSQq
this.items = items; <_c8F!K)T
} fW[ .Q0
7Ie=(x8):
publicint getPageSize(){ c8T| o=`k6
return pageSize; O4Q"2
} 5YneoM]Q
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publicvoid setPageSize(int pageSize){ dyk(/#*7W
this.pageSize = pageSize; |s;']
} 2$ &B@\WY
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publicint getTotalCount(){ ITg<u?z_
return totalCount; ~Hu!iZ2]
} Xdwpn+7s
5 5m\,UG7
publicvoid setTotalCount(int totalCount){ 2WTOu x*
if(totalCount > 0){ LM+d3|gSV
this.totalCount = totalCount; Bhv$
int count = totalCount / R8_I ASs
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pageSize; [h8s0
if(totalCount % pageSize > 0) TDUY& 1[
count++; OQ-
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indexes = newint[count]; vP=68muD
for(int i = 0; i < count; i++){ '_^T]fr}
indexes = pageSize * i")0 3b
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i; 7YR|6{@
} 1`YU9?
}else{ *ziR &Fr!
this.totalCount = 0; /isalOT
} I/%v`[
} [:FiA?O]
#c5jCy}n
publicint[] getIndexes(){ .] sJl
return indexes; jj1\oyQ8
} nYFrp)DLK
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publicvoid setIndexes(int[] indexes){ NC#F:M;b
this.indexes = indexes; 0/b
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} u '7h(1@
t*=[RS*
publicint getStartIndex(){ UXs)$
return startIndex; xH xTL>,?
} Dlq!:dF{&
#<S*MGp!=
publicvoid setStartIndex(int startIndex){ aPVzOBp
if(totalCount <= 0) #3QPcoxa
this.startIndex = 0; 0z8?6~M;<
elseif(startIndex >= totalCount) 68Gywk3]=u
this.startIndex = indexes -}9^$}PR
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[indexes.length - 1]; ^>?=L\[
elseif(startIndex < 0) +yp:douERi
this.startIndex = 0; ?B1Zfu0
else{ \3$!) z
this.startIndex = indexes l! F$V;R
`oJQA$UD
[startIndex / pageSize]; yGdX>h
} +cfEyiub
} s*ZE`/SM3
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publicint getNextIndex(){ yQiY:SH
int nextIndex = getStartIndex() + m$fEk,d
@PEFl"
pageSize; sD:o
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if(nextIndex >= totalCount) |oi+|r
return getStartIndex(); #$I@V4O;#
else _x!idf
return nextIndex; `m7<_#Y
} STp9Gh-
q(?+01
publicint getPreviousIndex(){ H#~gx_^U
int previousIndex = getStartIndex() - SM2Lbfp!u
x
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pageSize; 7nek,8b
if(previousIndex < 0) fQJ`&9m*BF
return0; ^#HaH
else H<(F$7Q!\
return previousIndex; D\acA?d`
} \c<
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} RbAl_xKI
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抽象业务类 )`DVPudiy
java代码: /4G1,T_,
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/** CS7b3p!I
* Created on 2005-7-12 ?veeW6E(
*/ 5/=$p:E>
package com.javaeye.common.business; o,*m,Qc
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import java.io.Serializable; )A8#cY!<
import java.util.List; 0D(8-H
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import org.hibernate.Criteria; xMJ-=
import org.hibernate.HibernateException; 6}^x#9\
import org.hibernate.Session; J,=K1>8s
import org.hibernate.criterion.DetachedCriteria; 74Jx \(d
import org.hibernate.criterion.Projections; _3`GZeGV
import &}"kF\
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org.springframework.orm.hibernate3.HibernateCallback; h4hAzFQ.s
import SZWNN#w60?
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org.springframework.orm.hibernate3.support.HibernateDaoS Y&6jFT_
[vi
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upport; w
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import com.javaeye.common.util.PaginationSupport; REh"/d
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public abstract class AbstractManager extends |
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HibernateDaoSupport { 3r~8:F"g
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privateboolean cacheQueries = false; mB`HPT
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privateString queryCacheRegion; jJ2rfdfj
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publicvoid setCacheQueries(boolean {]IY;cL
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cacheQueries){ LQF;T7VKS)
this.cacheQueries = cacheQueries; Es[3Ppz
} D1RQkAZS
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publicvoid setQueryCacheRegion(String E2zL-ft.
}9ulHiR
queryCacheRegion){ (#dR\Di
this.queryCacheRegion = 0*MUe1{
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queryCacheRegion; {L$$"r,
} (cVIjo+::
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publicvoid save(finalObject entity){ |E6Thvl$
getHibernateTemplate().save(entity); 5YrzOqg=
} LuRCkKJ
61_PSScSY
publicvoid persist(finalObject entity){ s(X\7Hz_nC
getHibernateTemplate().save(entity); TFHYB9vV
} ^2dQVV.
&DW !$b
publicvoid update(finalObject entity){ =bp'5h8_
getHibernateTemplate().update(entity); l9QI lTc7
} O
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publicvoid delete(finalObject entity){ O}C*weU
getHibernateTemplate().delete(entity); F*G]Na@6D
} whN<{AG
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publicObject load(finalClass entity, \6AM?}v
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finalSerializable id){ <mJ8~
return getHibernateTemplate().load q>+!Ete1p
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(entity, id); /{j._4c
} l>|scs;TI
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publicObject get(finalClass entity, kh}h(z^
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finalSerializable id){ -V2f.QE%
return getHibernateTemplate().get JV,h1/a("
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(entity, id); fNda&
} md bi@ms@
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publicList findAll(finalClass entity){ C6g p}%
return getHibernateTemplate().find("from Jr'a_(~
X#by Dg
" + entity.getName()); 8@doKOA~T
}
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publicList findByNamedQuery(finalString pq_U?_5Z'r
bp" @p:
namedQuery){ u[SqZftmO
return getHibernateTemplate u-jV@Tz
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().findByNamedQuery(namedQuery); "([gN:
} `
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publicList findByNamedQuery(finalString query, .p Mwa
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finalObject parameter){ 8,F|*YA
return getHibernateTemplate #""T>+
$KT)Kz8tF
().findByNamedQuery(query, parameter); \FX"A#
} z&c}
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publicList findByNamedQuery(finalString query, mcidA%
.*n*eeD,
finalObject[] parameters){ V$FZVG/@#
return getHibernateTemplate >\~Er@
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().findByNamedQuery(query, parameters); kVCWyZh4
} unqUs08
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publicList find(finalString query){ M/lC&F(
return getHibernateTemplate().find 3(t3r::&
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(query); +84
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} .x] pJ9
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publicList find(finalString query, finalObject t_16icF9U
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parameter){ b>i5r$S8G
return getHibernateTemplate().find R
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(query, parameter); a[z$ae7
} EbX!;z
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public PaginationSupport findPageByCriteria N(yd<Mw
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(final DetachedCriteria detachedCriteria){ g]N'6La
return findPageByCriteria lIx./Nf
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); IC8%E3
} Dm}M8`|X
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public PaginationSupport findPageByCriteria _Yp~Oj
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(final DetachedCriteria detachedCriteria, finalint .p o,.}
u)r:0;5
startIndex){ Jd v;+HN[
return findPageByCriteria I
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@OFxnF`
(detachedCriteria, PaginationSupport.PAGESIZE, RjgJIVm(
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startIndex); H[OgnnM
} TXyiCS3
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public PaginationSupport findPageByCriteria lsOfpJ
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(final DetachedCriteria detachedCriteria, finalint VlL%dN;
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pageSize, 1kvs2
finalint startIndex){ y5O &9Ckw
return(PaginationSupport) ; Ad5Jk
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getHibernateTemplate().execute(new HibernateCallback(){ N]|>\
publicObject doInHibernate H|wP8uQC
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(Session session)throws HibernateException { <;~u@^>
Criteria criteria = s/C'f4
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detachedCriteria.getExecutableCriteria(session); hLk6Hqr7
int totalCount = XGC\6?L~
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((Integer) criteria.setProjection(Projections.rowCount $7g+/3Fu^
BbCO K
()).uniqueResult()).intValue(); x{<l8vL=-c
criteria.setProjection k1zK3I&c_
7 [u>#8
(null); IOuqC.RJ}o
List items = XM`
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criteria.setFirstResult(startIndex).setMaxResults 4G&dBH
zUv#%Q8vw
(pageSize).list(); btq4diW
PaginationSupport ps = fHH
Bi :!"Nw[X
new PaginationSupport(items, totalCount, pageSize, ^IIy>
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startIndex); uZ-ZZE C
return ps; C}Kl!
} pWJEFm
}, true); wB \`3u4
} p&]V!O
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public List findAllByCriteria(final |3@DCbT
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DetachedCriteria detachedCriteria){ flFdoEV.U)
return(List) getHibernateTemplate tB,(12@W
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().execute(new HibernateCallback(){ B#SVN Lv
publicObject doInHibernate y5m2u8+
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(Session session)throws HibernateException { bD:0k.`
Criteria criteria = z"UC$
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detachedCriteria.getExecutableCriteria(session); 0C/ZcfFU~
return criteria.list(); oYStf5
} RK|*yt"f"
}, true); p.=9[`
} }>0>OqvF
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public int getCountByCriteria(final CYW@Km{e
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DetachedCriteria detachedCriteria){ NSB6 2
Integer count = (Integer) t n5
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getHibernateTemplate().execute(new HibernateCallback(){ p#ar`-vQ
publicObject doInHibernate A:r?#7 Ma
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(Session session)throws HibernateException { 6-
i.*!I 8
Criteria criteria = e;6KxvX~
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detachedCriteria.getExecutableCriteria(session); 3Hom0g,V4
return D'#Q`H
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criteria.setProjection(Projections.rowCount vv @m{,7#Y
E
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()).uniqueResult(); : OY~Q3
@
} Pj-INc96
}, true); ilL0=[2
return count.intValue(); k k3^m1
} D%YgS$p[M$
} fo@^=-4A-
}#O!GG{
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用户在web层构造查询条件detachedCriteria,和可选的 6@J=n@J$p
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 my.EvN
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PaginationSupport的实例ps。 $E\|\g
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ps.getItems()得到已分页好的结果集 ' [
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ps.getIndexes()得到分页索引的数组 g\JJkXjD#
ps.getTotalCount()得到总结果数 H$(bSw$
ps.getStartIndex()当前分页索引 ~f1g"
ps.getNextIndex()下一页索引 9B: 3Ha=
ps.getPreviousIndex()上一页索引 18>cfDh;N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 5AYOM=O]t
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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 ]k0
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一下代码重构了。 <>cS@V5j
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我把原本我的做法也提供出来供大家讨论吧: uepyH
d8j1L/e
首先,为了实现分页查询,我封装了一个Page类: g`7XE
java代码: `Lf'/q
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/*Created on 2005-4-14*/ WSkGVQu
package org.flyware.util.page; nM
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/** _'u]{X\k{J
* @author Joa 4q$~3C[
* ^QB[;g.O
*/ a V3:{oL
publicclass Page { }'X=&3m
\oQ]=dDCd%
/** imply if the page has previous page */ ie}OZM
privateboolean hasPrePage; aER|5!7(2\
I5$P9UE+^9
/** imply if the page has next page */ <AHpk5Sn{
privateboolean hasNextPage; %\As
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/** the number of every page */ v<qh;2
privateint everyPage; Lpchla$
d"$8-_K
/** the total page number */ =8kmFXo
privateint totalPage; h6
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)
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/** the number of current page */ ]Z JoC!u
privateint currentPage; Q=\
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/** the begin index of the records by the current ,b+NhxdZ
o_b[ *
query */ }2A6W%^>]
privateint beginIndex; 15$xa_w}L
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/** The default constructor */ # kI>
public Page(){ o9?@jjqH
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} $|4C]Me (
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/** construct the page by everyPage 8OfQ :
* @param everyPage (z?HyxRT
* */ 1C[9}}
public Page(int everyPage){ rCyb3,W
this.everyPage = everyPage; fGgt[f[
}
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k1 5vs
/** The whole constructor */ JuRoeq.
public Page(boolean hasPrePage, boolean hasNextPage, mgxIxusR
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int everyPage, int totalPage, ~m%[d.
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int currentPage, int beginIndex){ ,N/@=As9$
this.hasPrePage = hasPrePage; k<1yv$/mW
this.hasNextPage = hasNextPage; ,m=F
H?5
this.everyPage = everyPage; Ku;fZN[g
this.totalPage = totalPage; ?-??>& z
this.currentPage = currentPage; myx/ |-V"F
this.beginIndex = beginIndex; 7AG|'s['=
} ]{-.?W*$
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/** T.q2tC[bR
* @return a|ft l&uk
* Returns the beginIndex. J5@08bZm
*/ 91
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publicint getBeginIndex(){ <+8'H:wz
return beginIndex; }v1wpv/b(
} 5Iu5N0cn
CB7dr&>
/** ?7{U=1gb$
* @param beginIndex *0WVrM06?
* The beginIndex to set. (1/Sf&2i
*/ 8K8u|]i
publicvoid setBeginIndex(int beginIndex){ 3)OZf{D[
this.beginIndex = beginIndex; EIi<g2pM(
} gv!8' DKn
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/** !3Dq)ebBz
* @return $Dg-;I
* Returns the currentPage. $CcjuPsK
*/ u ExLj6
publicint getCurrentPage(){ $+eeE
return currentPage; <y 4(!z"
} Xz]l#w4Pp
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/** ktu?-?#0,
* @param currentPage >OG189O
* The currentPage to set. B`pBIUu
*/
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publicvoid setCurrentPage(int currentPage){ :4AQhn^;"
this.currentPage = currentPage; 09Hrn
} o'Bd. B
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/** 2g(_Kdj*{
* @return "tEp8m
* Returns the everyPage. ?pL|eS7
*/ ulR yt^bx|
publicint getEveryPage(){ eAHY/Y!
return everyPage; dT`nR"
} ~Nh6po{
O{ :{P5
/** |$.?(FZYu
* @param everyPage 8lQ/cGAc
* The everyPage to set. b,~'wm8:A
*/ |N,^*xP(6
publicvoid setEveryPage(int everyPage){ !G%!zNA S
this.everyPage = everyPage; v gW(l2,@
} ]dycesc'
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/** 3}L3n*Ft#.
* @return Ff<cY%t
* Returns the hasNextPage. ]0i[=
*/ mR}8} K]L
publicboolean getHasNextPage(){ 5 nt3gVy
return hasNextPage; l|g*E.:4
} /%YW[oY{V
E2hsSqsu=
/** ~B<\#oO
* @param hasNextPage 0+&WIs
* The hasNextPage to set. &Vj@){
*/ sbvP1|P8%
publicvoid setHasNextPage(boolean hasNextPage){ ueg%yvO
this.hasNextPage = hasNextPage; r$<!?Z
} 6O4*OR<&
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/** piIZ*@'
* @return Q}#4Qz~n
* Returns the hasPrePage. :GvC#2p
*/ COi15( G2
publicboolean getHasPrePage(){ c<13 r=+
return hasPrePage; j)ic7b
} %/eG{oh-
?M90K)&g{
/** 2_$8Ga
* @param hasPrePage \:'GAByy
* The hasPrePage to set. nS#F*)
*/ \t{iyUxY
publicvoid setHasPrePage(boolean hasPrePage){ #kQ! GMZH
this.hasPrePage = hasPrePage; l@4pZkdq
} U" @5R[=F-
s.(.OXD&
/** E2Sj IR}
* @return Returns the totalPage. clDn=k<
* m.P
F'_)/
*/ \]Y<d
publicint getTotalPage(){ ]xf89[;0
return totalPage; Y1o[|ytW
} mI2Gs)SO
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/** ,WdSJ BK'a
* @param totalPage =Vh]{y~$
* The totalPage to set. LBio$67F
*/ CCpRQKb=
publicvoid setTotalPage(int totalPage){ xpZ@DK;
this.totalPage = totalPage; }[%F
} YBY;$&9
52^3N>X4X
} ?Gf'G{^}
xb7!!PR
!/`AM<`o
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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 &tkPZ*}#1
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个PageUtil,负责对Page对象进行构造: iMry0z
java代码: lBn<\Y!^
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Ym%#"
/*Created on 2005-4-14*/ oe6Ex5h
package org.flyware.util.page; !}A`6z
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import org.apache.commons.logging.Log; [:,|g;=Y}
import org.apache.commons.logging.LogFactory; "=s dn
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/** 'Q'-7z-6
* @author Joa **AJFc
* qPN
*/ 5m;pHgkb
publicclass PageUtil { Jbima>
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privatestaticfinal Log logger = LogFactory.getLog c5CxR#O
v&sp;%I6=
(PageUtil.class); u 'ng'j'
\#h=pz+jb
/** |rpMwkR
* Use the origin page to create a new page HVC|0}
* @param page %[,^2s
* @param totalRecords Q1h v2*/U
* @return Pi&\GMzd
*/ !/F-EJOH6C
publicstatic Page createPage(Page page, int B_r:da CS:
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totalRecords){ 4!glgEE*
return createPage(page.getEveryPage(), <^Q`
y
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page.getCurrentPage(), totalRecords); rI:]''PR
} I1ibrn
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/** )P/~{Ci:T&
* the basic page utils not including exception
*!EHs04
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handler oRn 5blj
* @param everyPage IetV ]Ff6
* @param currentPage qyzeAK\Ia
* @param totalRecords (w 'k\y
* @return page <RkJ7Z^
*/ Io;26F""
publicstatic Page createPage(int everyPage, int lce~6}
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currentPage, int totalRecords){ *u<@_Oa
everyPage = getEveryPage(everyPage); MU_
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currentPage = getCurrentPage(currentPage); A`1/g{Ha
int beginIndex = getBeginIndex(everyPage, 0xutG/-&N
`^E(P1oJ3
currentPage); )3_g&&
int totalPage = getTotalPage(everyPage, Z Q9's
`=foB-(zt
totalRecords); pQxi0/d p
boolean hasNextPage = hasNextPage(currentPage, qoD
M!~
!FnH;
totalPage); X"G3lG
boolean hasPrePage = hasPrePage(currentPage); yIThzyS
hta$k%2
returnnew Page(hasPrePage, hasNextPage, kA:cz$)
everyPage, totalPage, 8<ri"m,
currentPage, QO~TuC
>^Z!
beginIndex); `S7${0e
} cE=v566
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privatestaticint getEveryPage(int everyPage){ >&9Iy"
return everyPage == 0 ? 10 : everyPage; {z%%(,I
}
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privatestaticint getCurrentPage(int currentPage){
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return currentPage == 0 ? 1 : currentPage; ~F]- +|
} Om2
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privatestaticint getBeginIndex(int everyPage, int eqeVz`
4LBjqv,P
currentPage){ Pl1:d{"d
return(currentPage - 1) * everyPage; T%P0M*
} y::KjB 0
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h
privatestaticint getTotalPage(int everyPage, int @sfV hWG
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totalRecords){ 7:x.08
int totalPage = 0; \hi{r@k>}
v#-%_V>ph
if(totalRecords % everyPage == 0) =b`>ggw#
totalPage = totalRecords / everyPage; 3XL0Pm
else R0. `2=
totalPage = totalRecords / everyPage + 1 ; *ArzXhs[
mXhr: e
return totalPage; ,{'~J @
} 1-w1k^e
guwnYS
privatestaticboolean hasPrePage(int currentPage){ j{p0yuZ)<
return currentPage == 1 ? false : true; ? _HTOOa
} W!IK>IW"
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privatestaticboolean hasNextPage(int currentPage,
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K<s\:$VVh
int totalPage){ oWXvkDN
return currentPage == totalPage || totalPage == WqYl=%x"{V
cG"jrQ
0 ? false : true; /eIwv31
} )}paQmy#
c:=Z<0S;
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} l8^^ O
=FwFqjvl
RCxqqUS\C
|$1j;#h
VLQfuh;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 !_x-aro3<
T \0e8"iZ
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 DK4V/>@8
{{2ZWK 6|
做法如下: 4[Oy3.-c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Q%t8cJL
Q^mJ _~
的信息,和一个结果集List: ?+5K2Zk
java代码: 8(g:i#~
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/*Created on 2005-6-13*/ bZtjg
package com.adt.bo; t3bN
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import java.util.List; {H0B"i
M?F({#]
import org.flyware.util.page.Page; 6J&L5E
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/** ,&l>^w/
* @author Joa T_B$
*/ e%UFY-2
publicclass Result { lT$A;7[
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private Page page; hg\$>W~2
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private List content; u1>| 2D
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/** 5ue{&z
@T
* The default constructor N^`F_R1Z
*/ V1"+4&R^T_
public Result(){ ]1p&*xX:Bj
super(); [qid4S~r,&
} ]LP&v3
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/** KeXQ'.x5O
* The constructor using fields >B~p[wh0
* .\1XR
* @param page QEtZ]p1H@
* @param content 1Rwk}wL
*/ bh_i*DJ]
public Result(Page page, List content){ o1kLT@VCl
this.page = page; )7J@A%u
this.content = content; _=,[5"
} %iF<
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@^%zh
/** N5oao'7|A
* @return Returns the content. .eJ4F-V
*/ HM--`RJ
publicList getContent(){ 6K*7%8Y/G
return content; WO_cT26Y
} =|uX?
c< \:lhl
/** n; !t?jnf.
* @return Returns the page. =;c? 6{<1
*/ kGX`y.-[
public Page getPage(){ #9p{Y}2#
return page; gxL5%:@
} '<8ewU
1LcQ*d
/** SOeL@!_
* @param content *gZ4Ub|O
* The content to set. qTiX;e\W
*/ m"@M~~bh
public void setContent(List content){ ,/JrQWgD
this.content = content; {w{|y[[d~
} zneK)C8&q3
`@=}5 9+|
/** }%_x T
* @param page G4AX8@;U
* The page to set. /koNcpJ
*/ jskATA
/
publicvoid setPage(Page page){ bxEb2D
this.page = page; ZK_IK)g
} vNi7=3
} TZPWMCN4
pD.7ib^
D='/-3f!F]
!^G+@~U
<@5#
2. 编写业务逻辑接口,并实现它(UserManager, s`GSc)AI
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UserManagerImpl) ){R_o5
java代码: uXu'I
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;
7P:0XML}
/*Created on 2005-7-15*/ wdoA>a?q
package com.adt.service; OFCkQEG=y>
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import net.sf.hibernate.HibernateException; |~rDEv3
t`H^!
b
import org.flyware.util.page.Page; 6Z|/M6f
(/Z~0hA[Q
import com.adt.bo.Result; %+FM$xyJ
o<@2zhuhrx
/** )v8;\1`s:
* @author Joa )^g}'V=vIr
*/ tkV:kh< L~
publicinterface UserManager { M)Tv(7
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public Result listUser(Page page)throws rm(<?w%'?
#qm<4]91
HibernateException; aztP`S$h
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} Af
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(= uwx#
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t<}'/
)
java代码: DV*8Mkzg
dFo9O!YX[f
pRUN[[L
/*Created on 2005-7-15*/ "`C|;\w
package com.adt.service.impl; -(Taj[;[
xgsD<3
import java.util.List; G\Toi98d*
dq"b_pr;
import net.sf.hibernate.HibernateException; )0fQ(3oOg
0MrtJNF]_O
import org.flyware.util.page.Page; p^ 9QYR
import org.flyware.util.page.PageUtil; REnRpp$
qC.jXU?rO
import com.adt.bo.Result; L.l%EcW=,
import com.adt.dao.UserDAO; ?ti7iBz?
import com.adt.exception.ObjectNotFoundException; HBo^8wN
import com.adt.service.UserManager; .;iXe
Ai(M06P:h
/** Q*( ]&qr"E
* @author Joa .eK1xwhJ
*/ `k^
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publicclass UserManagerImpl implements UserManager { G/2@Mn-
hLYSYMUb
private UserDAO userDAO; ,'={/)c<
[$8*(d"F'
/** 8T$:^HW
* @param userDAO The userDAO to set. `lN1u'(:
*/ 6(DK\58
publicvoid setUserDAO(UserDAO userDAO){ g^}X3NUn
this.userDAO = userDAO; 2s?j5 Sd
} <uu1e@P
yY[[)
/* (non-Javadoc) Drk9F"J
* @see com.adt.service.UserManager#listUser F@"Xd9q?
uC 5mxZ
(org.flyware.util.page.Page) (}gF{@sn
*/ (gl CTF9v
public Result listUser(Page page)throws K34ca-~
tojJQ6;J
HibernateException, ObjectNotFoundException { _
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int totalRecords = userDAO.getUserCount(); 3`SLMPI
if(totalRecords == 0) g]X4)e]
throw new ObjectNotFoundException T/)$}#w0i
W{1=O)w
("userNotExist"); JEU?@J71O
page = PageUtil.createPage(page, totalRecords); b0riiF
List users = userDAO.getUserByPage(page); -58r*[=8
returnnew Result(page, users); wf6ZzG:
} V6BCW;
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} b0m1O.&I_
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tG^Oj:
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pFGdm3pV
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 J@(*(oQb
VskyRxfdW3
询,接下来编写UserDAO的代码: 67/hhO
3. UserDAO 和 UserDAOImpl: |~8iNcIS
java代码: XHlPjw
7I(Sa?D:
+3]@0VM26;
/*Created on 2005-7-15*/ +%UXI$v
package com.adt.dao; /D 2v1
9.#\GI ;
import java.util.List; + 5sTGNG
n#,AZ&
import org.flyware.util.page.Page; )I.[@#-
Z-Bw?_e_K
import net.sf.hibernate.HibernateException; z=n"cE[KtB
6>Lr
/** n&FN?"I/]
* @author Joa ^[\F uSL
*/ -Ww'wH'2
publicinterface UserDAO extends BaseDAO { 4K[U*-\"
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publicList getUserByName(String name)throws ~?[%uGI0h
oKA8)~Xqou
HibernateException; 5<,}^4wWZ
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publicint getUserCount()throws HibernateException; c<pr1g
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publicList getUserByPage(Page page)throws 2[qO;js
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HibernateException; LPO3B W
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} HMrS::
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[=S@lURzm@
java代码: M:Xswwq
!yG{`#NZZ
Y.[^3
/*Created on 2005-7-15*/ r,L#JR w#-
package com.adt.dao.impl; EAj2uV
z"=#<C
import java.util.List; ,]y)Dy
efl6U/'Ij
import org.flyware.util.page.Page; 7W5FHZd'
l?pZdAE
import net.sf.hibernate.HibernateException; H2E!A2\m
import net.sf.hibernate.Query; wu/]M~XwI
Z+(V'e;
import com.adt.dao.UserDAO; [@uL)*o_#
j'X]bd'
/** kNd[M =%
* @author Joa #- f7hg*
*/ mI@E>VCV[
public class UserDAOImpl extends BaseDAOHibernateImpl aq oT
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implements UserDAO { CP]BSyim'
vd9l1"S
/* (non-Javadoc) 2|qE|3&{'
* @see com.adt.dao.UserDAO#getUserByName
[^8*9?i4
FxTOc@<
(java.lang.String) YB*ZYpRVl
*/ a4 O
publicList getUserByName(String name)throws (C!u3ke2D
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h(
HibernateException { r*p<7
String querySentence = "FROM user in class [NQ`S
~_:
: \:jIP
com.adt.po.User WHERE user.name=:name"; 5owUQg,W
Query query = getSession().createQuery <6Y o%xt
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(querySentence); PHyS^J`
query.setParameter("name", name); v,KH2 (N
return query.list(); ?Q]&d!UCs
} #hH "g
A@?2qX^4
/* (non-Javadoc) u f.Zg;Vc
* @see com.adt.dao.UserDAO#getUserCount() =L
7scv%i
*/ ]O,!B''8k
publicint getUserCount()throws HibernateException { A%"mySW
int count = 0; HZ>Xm6DnC5
String querySentence = "SELECT count(*) FROM CTD{!I(
kgEGL]G>
user in class com.adt.po.User"; s4@AK48
Query query = getSession().createQuery xzyV|(
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(querySentence); W&A22jO.1
count = ((Integer)query.iterate().next (fUXJ$
V/.Y]dN5
()).intValue(); #W @6@Mv
return count; @-NdgM<
} x&8HBF'
9} :n
/* (non-Javadoc) d?$FAy'o5
* @see com.adt.dao.UserDAO#getUserByPage |p4F^!9
`9(TqcE
(org.flyware.util.page.Page) Co4QWyt:
*/ 2ZNTj u7h
publicList getUserByPage(Page page)throws xm6=l".%z
^.&