Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F7<M{h5s
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 A@~9r9Uf
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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 cWnEp';.
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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 5dv|NLl
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分页支持类: k@fxs]Y_L
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java代码: 15_"U+O(/
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package com.javaeye.common.util; ,8DC9yM,
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import java.util.List; 0>m$e(Z
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publicclass PaginationSupport { v "2A?
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publicfinalstaticint PAGESIZE = 30; A
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privateint pageSize = PAGESIZE; 9/8+R%
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privateList items; ?ZTA3mV?+
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privateint totalCount; nd\$Y
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privateint[] indexes = newint[0]; (Qw >P42J
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privateint startIndex = 0; jKcl{',
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public PaginationSupport(List items, int @=g{4(zR^
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totalCount){ \|vo@E
setPageSize(PAGESIZE); p}~Sgi
setTotalCount(totalCount); V,zFHXO
setItems(items); ~9YEb
setStartIndex(0); ?pQ0*
O0
} 86KK Y2
%*q^i}5)E
public PaginationSupport(List items, int V9KRA 1
9Pvv6WyKy
totalCount, int startIndex){ yEB#*}K?
setPageSize(PAGESIZE); j<WsFVS
setTotalCount(totalCount); Md9y:)P@Y
setItems(items); pQZ`dS\
setStartIndex(startIndex); !`H!!Kg0L
} w}/+3z
p1GP@m,^n0
public PaginationSupport(List items, int `}ZtK574
18~jUYMV
totalCount, int pageSize, int startIndex){ Z9MU%*N
setPageSize(pageSize); Le-t<6i-V#
setTotalCount(totalCount); 'o=DGm2H
setItems(items); <QgpePyoN
setStartIndex(startIndex); sc-+?i
} !F?j'[s8]
<2O#!bX1
publicList getItems(){ y'6l fThT
return items; |d\1xTBLp
} 6[FXgCb
<D& Ep
publicvoid setItems(List items){ {qSMJja !t
this.items = items; s{c|J#s
} $? Z}hU
.LM|@OeaD!
publicint getPageSize(){ _`*G71PS
return pageSize; #xR=U"
} > B;YYj~f}
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publicvoid setPageSize(int pageSize){ Dm?:j9o]g
this.pageSize = pageSize; d=\TC'd"{
} lQgavP W!
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publicint getTotalCount(){ _iA oNT!
return totalCount; `uDOIl
} kTzO4s?
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publicvoid setTotalCount(int totalCount){ `S3)uV]I
if(totalCount > 0){ 0}`
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this.totalCount = totalCount; `Y!8,(5#
int count = totalCount / =(R3-['QIb
%b h:c5
pageSize; <Pf4[q&wM
if(totalCount % pageSize > 0) L*rCUv `
count++; [Tvdchl OC
indexes = newint[count]; nXuy&;5TL,
for(int i = 0; i < count; i++){ >,Zn~8&Z
indexes = pageSize * @5??`n
@ I&k|\
i; qm9=Ga5
} D#,A_GA{A
}else{ ([SJ6ff]&
this.totalCount = 0; vwAhNw2-
} s[7/w[&
} (B*,|D[J@i
;i [;%
publicint[] getIndexes(){ oFzmH!&ED
return indexes; @eESKg(,
} jW^]N$>
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publicvoid setIndexes(int[] indexes){ ,l,q;]C%
this.indexes = indexes; I4<_y5
} ZBH^0
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publicint getStartIndex(){ AnE]
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return startIndex; @d0~'_vtB
} 0a!|*Z
W8-vF++R
publicvoid setStartIndex(int startIndex){ t3v_o4`&
if(totalCount <= 0) X-CoC
this.startIndex = 0; |NTqJ j
elseif(startIndex >= totalCount) 8"[{[<-
this.startIndex = indexes ]XX>h~0
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[indexes.length - 1]; ^mut-@ N9
elseif(startIndex < 0) !F Zg'
9
this.startIndex = 0; C0^r]^$Z
else{ R%9,.g<
this.startIndex = indexes
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nb*`GE
[startIndex / pageSize]; '!MKZKer
} s gZlk9x!Q
} 3<1x>e2nT
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publicint getNextIndex(){ 05jjLM'e
int nextIndex = getStartIndex() + zG%'Cw)8
bx-:aC)]2
pageSize; ssH[\i
if(nextIndex >= totalCount) IO2@^jup
return getStartIndex(); oe=1[9T"
else o>]z~^c
return nextIndex; m*lcIa
} M D&7k,!
EAC I>
publicint getPreviousIndex(){ F0kAQgUv
int previousIndex = getStartIndex() - W]>%*n
(*T$:/zIS
pageSize; 2P=~6(
if(previousIndex < 0) L{XW2c$h
return0; Vhe$vH
else u3Zu ~C
return previousIndex; X<v1ES$
} P*ZMbAf.
=L?2[a$2;
} /*"pylm
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抽象业务类 PH^Gjm
java代码: (bB"6
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/** #D ]CuSi
* Created on 2005-7-12 ,.|/B^jV
*/ {lppv(U
package com.javaeye.common.business; U+["b-c
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import java.io.Serializable; h$6~3^g:P
import java.util.List; lO 0}
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import org.hibernate.Criteria; e:rbyzf#
import org.hibernate.HibernateException; ;Z`R!
import org.hibernate.Session; b0x%#trA{
import org.hibernate.criterion.DetachedCriteria; R.
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import org.hibernate.criterion.Projections; /wP2Wnq$
import Qf'g2
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org.springframework.orm.hibernate3.HibernateCallback; z'"Y+EWN
import [1z.JfC :S
:"@-Bcln
org.springframework.orm.hibernate3.support.HibernateDaoS bg)}-]u]
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upport; zXbA$c
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import com.javaeye.common.util.PaginationSupport; *=T(ncR['
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public abstract class AbstractManager extends 9E[==2TO
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HibernateDaoSupport { K7nyQGS
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privateboolean cacheQueries = false; _]eyt_
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privateString queryCacheRegion; ',rK\&lL6
S a}P
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publicvoid setCacheQueries(boolean {:Kr't<XzF
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cacheQueries){ B`jq"[w]-
this.cacheQueries = cacheQueries; [r'A8!/|[
} ki1j~q
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publicvoid setQueryCacheRegion(String aEVy20wd
} .<(L
queryCacheRegion){ Ji6.-[:
this.queryCacheRegion = #~.RJ%
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queryCacheRegion;
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} dT (i*E\j
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publicvoid save(finalObject entity){ MpIiHKQ
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getHibernateTemplate().save(entity); lXzm)
} !aL=R)G&e
_c5*9')-)
publicvoid persist(finalObject entity){ 4:/^ .:
getHibernateTemplate().save(entity); Wu8^Z Z{
} ]e+&Pxw]e
$q.}eb0
publicvoid update(finalObject entity){ QBN\wL8g
getHibernateTemplate().update(entity); v53|)]V
} pUW7p
#l7v|)9v
publicvoid delete(finalObject entity){ B<a` o&?
getHibernateTemplate().delete(entity); eg1F[~YL/
} ,(f W0d#
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publicObject load(finalClass entity, uv^x
<$otBC/%
finalSerializable id){ Htln <N
return getHibernateTemplate().load &
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4%I[.dBnM
(entity, id); SQ/HZ
} }6=)w@v
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publicObject get(finalClass entity, MX.?tN#F|H
D_)/.m
finalSerializable id){ 1X9s\JKQ
return getHibernateTemplate().get g#cet{>
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(entity, id); {Qn{w%!|
} LhM$!o?W
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publicList findAll(finalClass entity){ s{j A!T}
return getHibernateTemplate().find("from 7q5*grm
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" + entity.getName()); mVh;=>8K
} y~VI,82*
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publicList findByNamedQuery(finalString ='m%Iq7X
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namedQuery){ ,CuWQ'H
return getHibernateTemplate \k{[HfVvn
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().findByNamedQuery(namedQuery); PL3hrI 5
} 4z9lk^#"X
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publicList findByNamedQuery(finalString query, ^H{YLO
=Vazxt@[
finalObject parameter){ '
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return getHibernateTemplate {8`$~c
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().findByNamedQuery(query, parameter); P8ZmrtQm
} Y:, rN
sf# px|~9
publicList findByNamedQuery(finalString query, ffBd
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finalObject[] parameters){ 4l68+
return getHibernateTemplate 7mMMVz2
cO5zg<wF
().findByNamedQuery(query, parameters); c %Cbq0+2
} qMA-#
*f`P7q*
publicList find(finalString query){ S6a\KtVa
return getHibernateTemplate().find (Cfb8\~
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(query); PLMC<4$s
} Ki7t?4YE
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publicList find(finalString query, finalObject U V*Ruy-
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parameter){ 6)P.wW
return getHibernateTemplate().find CH
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(query, parameter); rjO{B`sV*
} w>=N~0@t
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public PaginationSupport findPageByCriteria 7v)p\#-
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(final DetachedCriteria detachedCriteria){ oOU_
Nay
return findPageByCriteria f.+1Ubq!5
}2Euz.0
(detachedCriteria, PaginationSupport.PAGESIZE, 0); \=bKuP(it
} tp>YsQy]8
19#>\9*
public PaginationSupport findPageByCriteria #Lp}j?Y
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(final DetachedCriteria detachedCriteria, finalint 4OpzGZ4+
*X2PT(e[
startIndex){ MGt>:&s(]
return findPageByCriteria #
#2'QNN
$T^q>v2u
(detachedCriteria, PaginationSupport.PAGESIZE, &ah%^Z4um
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startIndex); wK#*|
} yb?Pyq.D
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public PaginationSupport findPageByCriteria V|$PO
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p?,<{mAe
(final DetachedCriteria detachedCriteria, finalint wCruj`$
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pageSize, ^jwzCo-
finalint startIndex){ |%v:>XEO
return(PaginationSupport) G2)F<Y
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getHibernateTemplate().execute(new HibernateCallback(){ ,aC}0t
publicObject doInHibernate :TG;W,`.V
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(Session session)throws HibernateException { 40h$-
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Criteria criteria = fs&$?mHL){
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detachedCriteria.getExecutableCriteria(session); Q47R`"
int totalCount = J
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((Integer) criteria.setProjection(Projections.rowCount _lwKa,}
a*U[;(
()).uniqueResult()).intValue(); e'G=.:
criteria.setProjection Y$A2{RjRq
ng!cK<p
(null); Kq-1 b
List items = n9}BT^4 v
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criteria.setFirstResult(startIndex).setMaxResults ]h(Iun
Td'(RV
(pageSize).list(); /}8Au$nA
PaginationSupport ps = ,.cR @5qI
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new PaginationSupport(items, totalCount, pageSize, a(]&H
"
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startIndex); ~1wt=Ln>
return ps; 4A6Y
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} sA|SOAn
}, true); o&Xp%}TI
} =-fM2oiI:
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public List findAllByCriteria(final aH'fAX0bF
9]oT/ooM
DetachedCriteria detachedCriteria){ x"e;T,c
return(List) getHibernateTemplate IONo&~-l
`v``}8tm
().execute(new HibernateCallback(){ 8VMA~7^
publicObject doInHibernate
r+E!V'{C
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(Session session)throws HibernateException { WF~BCP$OR
Criteria criteria = z}u`45W+
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detachedCriteria.getExecutableCriteria(session); 8^y=YUT
return criteria.list(); s_IFl5D]
} _Fa\y ZX
}, true); Jj>Rzj!m
} iIX%%r+
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public int getCountByCriteria(final jc9C|r
Xpg-rxX
DetachedCriteria detachedCriteria){ :p/=KI_
Integer count = (Integer) )LFbz#;Y
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getHibernateTemplate().execute(new HibernateCallback(){ M*gvYo
publicObject doInHibernate _.; PLq~0
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(Session session)throws HibernateException { Yu_*P-Ja6
Criteria criteria = <1*.:CL"s
\#:
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detachedCriteria.getExecutableCriteria(session); ;7:} iKU
return 7CH&n4v
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criteria.setProjection(Projections.rowCount }'eef"DJ9
>ceC8"}J5M
()).uniqueResult(); C`i#7zsH
} '2lzMc>wvP
}, true); M11\Di1
return count.intValue(); @e3+Gs
} {L7Pha
} q<q IT
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用户在web层构造查询条件detachedCriteria,和可选的 ~O\A 0e
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 uE')<fVX(
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PaginationSupport的实例ps。 p]RQ-0
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ps.getItems()得到已分页好的结果集 ';FJs&=I
ps.getIndexes()得到分页索引的数组 >o1dc*
ps.getTotalCount()得到总结果数 @`L;_S+
ps.getStartIndex()当前分页索引 :VlA2Ih&q
ps.getNextIndex()下一页索引 q"2APvsvp
ps.getPreviousIndex()上一页索引 I~n4}}9M
. J O3#
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 9
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 >va_,Y}
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一下代码重构了。 1}wDc$O
9lYfII}4(
我把原本我的做法也提供出来供大家讨论吧: 0"OEOYs}
Qpmq@iL
首先,为了实现分页查询,我封装了一个Page类: 0o>C,
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java代码: {FvFah
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/*Created on 2005-4-14*/ HfSx*@\s
package org.flyware.util.page; b=lJ`|
59)w+AW
/** R*:$^v@4
* @author Joa no<$=(11i
* NRtH?&7
*/ r=n{3o+
publicclass Page { gd0)s1{9
9$HKP9G
/** imply if the page has previous page */ h<%$?h+}
privateboolean hasPrePage; 4u}Cki,vOK
=_-u;w1D
/** imply if the page has next page */ 2QaE&8vW
privateboolean hasNextPage; bp9RF
d{
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/** the number of every page */ 6a,8t
privateint everyPage; n%F _3`
,K,st+s|
/** the total page number */ h}SZ+G/L
privateint totalPage; jXA/G%:[
uluAqDz`
/** the number of current page */ pCIS82L
privateint currentPage; 0R)x"4Ww
Yg.[R]
UC
/** the begin index of the records by the current HZ'rM5Kq
F@Sk=l(
query */ z<5 5[~3
privateint beginIndex; TbD
=8 @DYz'
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/** The default constructor */ 0C :8X
public Page(){ j_g(6uZhz3
j ^j"w(a
} ly`
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{V>F69IU
/** construct the page by everyPage |-V:#1wR.]
* @param everyPage &233QRYM
* */ M6p\QKi
public Page(int everyPage){ 9 o,`peH
this.everyPage = everyPage; o+.L@3RT4
} bI
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/** The whole constructor */ &'fER-
public Page(boolean hasPrePage, boolean hasNextPage, pSlc (M>
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`r SOt*<
int everyPage, int totalPage, yq;[1O_9C
int currentPage, int beginIndex){ VrRF2(Kn?
this.hasPrePage = hasPrePage; L/rf5||@
this.hasNextPage = hasNextPage; JY CMW!~
this.everyPage = everyPage; 2om:S+3)2
this.totalPage = totalPage; 4ekwmw(ox
this.currentPage = currentPage; Cl&mz1Y;]1
this.beginIndex = beginIndex; 4E.9CjN1>
} ^(:~8 h
%l!A%fn(
/** 'EIe5Op
* @return ra'/~^9
* Returns the beginIndex. /HRKw
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*/ EFC+7 L(j
publicint getBeginIndex(){ Ni>Ns=n
return beginIndex; 60%nQhb
} n8Qv8
op`9(=DJ]
/** %}TJr]'F
* @param beginIndex "B:FSWM_-
* The beginIndex to set. E&cC2(w
*/ rEWJ3*Hb
publicvoid setBeginIndex(int beginIndex){ "yQBHYP
this.beginIndex = beginIndex; [mv? \HDa~
}
]+Whv%M
~!Sd|e:4
/** F3(SbM-
* @return )
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* Returns the currentPage. EmT_T3v
*/ Rr
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publicint getCurrentPage(){ YtvDayR>
return currentPage; r =x"E$
} yP3I^>AZ3
Ua
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/** $CMye; yL
* @param currentPage WOj}+?/3 R
* The currentPage to set. } +Sp7F1q
*/ Zy7kPL;b
publicvoid setCurrentPage(int currentPage){ "T=j\/Q
this.currentPage = currentPage; FUL3@Gb$UV
} $[A^8[//
+&7V@
/** DRm`y>.
* @return lU!_V%n
* Returns the everyPage. `_cv& "K9f
*/ -crMO57/
publicint getEveryPage(){ 3r+c&^
return everyPage; /b>xQ.G
} z` 6$p1U
PpFQoY7M
/** 'sIne>
* @param everyPage 2?7ID~\
* The everyPage to set. PsUO8g'\
*/ 82,^Pu
publicvoid setEveryPage(int everyPage){ RTlC]`IGT
this.everyPage = everyPage; 9 RDs`>v
} {v'eP[
?{ '_4n3O
/** T`@brL
* @return #+D][LH4
* Returns the hasNextPage. XFoSGqD
*/ J\+fkN<.
publicboolean getHasNextPage(){ yFk|8d-|
return hasNextPage; _k]R6V:
} R5e[cC8o.
<VD7(j]'^
/** C<teZz8/w
* @param hasNextPage fSd|6iFH
* The hasNextPage to set. \h'7[vkr
*/ <b"^\]l
publicvoid setHasNextPage(boolean hasNextPage){ jo&j<3i
this.hasNextPage = hasNextPage; &v0]{)PO
} <xeB9
)T9Cv8
/** ~/A2:}Cp=
* @return NpGi3>5
* Returns the hasPrePage. 8B-PsS|'
*/ EE]xZz>o
publicboolean getHasPrePage(){ ?<.a>"!
return hasPrePage; $s=` {v v
} h{7>>
`\(co;:
/** EXeV@kg
* @param hasPrePage %|x9C,0p#
* The hasPrePage to set. JJ1>)S}X-
*/ rPy,PQG2w
publicvoid setHasPrePage(boolean hasPrePage){ 6t7FklM%
this.hasPrePage = hasPrePage; L
*\[;.mk
} H2|'JA#v
<EqS
,cO^
/** Dn<3#V
* @return Returns the totalPage. )6%*=-
* e=h-}XRC
*/ !D1#3?L
publicint getTotalPage(){ LodP,\T
return totalPage; e%pohHI
} 7l-MVn_8
=U~53Tg
/** hwUb(pZ
* @param totalPage ,k_ b-/
* The totalPage to set. |in>`:qk
*/ e}5x6t
publicvoid setTotalPage(int totalPage){ ~*3Si(4l/
this.totalPage = totalPage; ~Qif-|[V
} Z0H_l/g
VXZYRr3F
} bx2<WdLyT
bn|HvLQ"1
%cDGs^lgA
Ndl{f=sjX-
!L;_f'\)6
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 vG6*[c8
i{N?Y0YQs0
个PageUtil,负责对Page对象进行构造: A-B>VX
java代码: Ln6emXqw
Xk!{UxQKQ
0x5\{f
/*Created on 2005-4-14*/ <WWZb\"{
package org.flyware.util.page; 4/{pz$
OH`zeI,[*
import org.apache.commons.logging.Log; VFawASwQ
import org.apache.commons.logging.LogFactory; S=S/]]e
!W,LG$=/
/** -wH0g^Ed
* @author Joa R#Yj%$E1
* 61QA<Wb
*/ A#']e 8
publicclass PageUtil { ,)U%6=o#}
eQyc<
privatestaticfinal Log logger = LogFactory.getLog SN")u
}9U_4k
(PageUtil.class); \c{sG\ >
?#<'w(^%#
/** \H>Psv{
* Use the origin page to create a new page MV3K'<Y
* @param page kz}Bc
F
* @param totalRecords )$1j"mV
* @return s+_8U}R
*/ J*K=tA
publicstatic Page createPage(Page page, int qYVeFSS
lmUCrs37
totalRecords){ 5`&@3
m9/
return createPage(page.getEveryPage(), 4`o0?_.'
/T {R\
page.getCurrentPage(), totalRecords); ~C>;0a;<:
} `K@N\VM
' xaPahx;
/** IAUc.VH
* the basic page utils not including exception wAu]U6!
M`Wk@t6>
handler q},,[t
* @param everyPage T1RY1hb|g>
* @param currentPage 9MJ:]F5+
* @param totalRecords h8M_Uk
* @return page 9
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*/ 1NZpd'$c
publicstatic Page createPage(int everyPage, int mHW%^R=
x]hG2on!
currentPage, int totalRecords){ 0n4( Rj|}2
everyPage = getEveryPage(everyPage); qmPu D/c
currentPage = getCurrentPage(currentPage); )gU:Up24|"
int beginIndex = getBeginIndex(everyPage,
)bYOy+2g
SJc*Rl>
currentPage); fUis_?!
int totalPage = getTotalPage(everyPage, %*<Wf4P"
CUc ,
totalRecords); RWu<
dY#ym
boolean hasNextPage = hasNextPage(currentPage, $L|+Z>x
w AdaP9h
totalPage); N`,,sw
boolean hasPrePage = hasPrePage(currentPage); w(S&X"~
`'r~3kP*NT
returnnew Page(hasPrePage, hasNextPage, 7)O+s/.P)
everyPage, totalPage, p]~PyzG!
currentPage, Hsov0
KCbOO8cQS
beginIndex); ('uUf!h?\
} `tT7&*Os
l{?9R.L
privatestaticint getEveryPage(int everyPage){ 5i{J0/'Xu)
return everyPage == 0 ? 10 : everyPage; O1X)
} wj'fdrY5h
X-bM`7'H
privatestaticint getCurrentPage(int currentPage){ bs%
RWwn
return currentPage == 0 ? 1 : currentPage; #/9Y}2G|]
} ? YIe<
bx6=LK
privatestaticint getBeginIndex(int everyPage, int 6W]C`
A=ez,87
currentPage){ #ax% n
return(currentPage - 1) * everyPage; )eSQce7H
} dci,[TEGu
hWn-[w/l_
privatestaticint getTotalPage(int everyPage, int =<#++;!I
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totalRecords){ 6v}q @z
int totalPage = 0; T8*;?j*@
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if(totalRecords % everyPage == 0) xrNe:Aj
totalPage = totalRecords / everyPage; &F;bg
else n^55G>"0|
totalPage = totalRecords / everyPage + 1 ;
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return totalPage; @kT@IQkri
} i-WP#\s
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privatestaticboolean hasPrePage(int currentPage){ |yj0Rv
return currentPage == 1 ? false : true; wwR}h I(
} ]<%NX
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privatestaticboolean hasNextPage(int currentPage, /-^{$$eu
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int totalPage){ F$|d#ny
return currentPage == totalPage || totalPage == KdTWi;mV2-
l]R7A_|
0 ? false : true; !xg10N}I
} wLfH/J
!w!k0z]
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} _D+J3d(Pjk
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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。 D#Mz#\4o
<O-R
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 Sy*p6DP
j,i)ecZ>
做法如下: .UN?Ak*R
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Gp?pSI,b.t
B'y)bY'_dS
的信息,和一个结果集List: :UKc:JVNM
java代码: gHXvmR"
)*.rl
YoQQ ,
/*Created on 2005-6-13*/ z-]ND
package com.adt.bo; hVZS6gU,x
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import java.util.List; nI73E
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import org.flyware.util.page.Page; pma=*
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/** Q!AGalP z
* @author Joa (v0Q.Q@<
*/ ]-+l.gVFW
publicclass Result { HYJEz2RF
/;y`6WG%2
private Page page; NOAz"m+o
04Uyr;y
private List content; S,Qa\\~z
qsQTJlq)
/** ][ 8`}ki 1
* The default constructor VhnIr#L+
*/ {?cF2K#
public Result(){ x'Nc}
super(); Z;dR:|%)
} 0d0ga^O
anKflt3
/** ?ZhBS3L
* The constructor using fields TOvsW<cM
* nF,zWr[x
* @param page \ZSq ZDq
* @param content :"i2`y;u
*/ i8*(J-M
public Result(Page page, List content){ \2Q#'
this.page = page; B'PS-Jr
this.content = content; T#H-GOY:
} Wrm3U/>e
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/** OSh'b$Z
* @return Returns the content. v>j<ky
*/ 0@
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publicList getContent(){ ! bX
return content; &pv*TL8
} \SJX;7ST
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/** w H`GzB"
* @return Returns the page. Ty;^3
*/ kH[thRk}
public Page getPage(){ $P #KL//
return page; ZxCXru1
} ]4FAbY2'h
|uM=pm;H
/** #~r+Z[(,p
* @param content F}B2nL&
* The content to set. {XnBj}C
*/ <#./q LSR
public void setContent(List content){ 3CSwcD
this.content = content; A(+V{1L'
} \~C/
Ga
<=Di):
/** ;hd%wmE
* @param page !xU\s'I+#
* The page to set. #=F{G4d)!=
*/ 8SupoS
publicvoid setPage(Page page){ T.WN9=N
this.page = page; \MAv's4b@
} BY$L[U;@T
} I5Rd~-="G
6>b#nFVJ
sei%QE]!/
qE6D"+1y7
Z|3[Y@c\
2. 编写业务逻辑接口,并实现它(UserManager, {{ 1qkG9$
oRmA\R*
UserManagerImpl) YTfi g{a
java代码: 2H~E~6G
#1'p?%K.
5VGZ5,+<<
/*Created on 2005-7-15*/ 7e)j|a-!<
package com.adt.service; EgOiJH
~UwqQD1p
import net.sf.hibernate.HibernateException; \`*]}48Z
h~=~csya:
import org.flyware.util.page.Page; :p$Q3
{J;(K~>?m
import com.adt.bo.Result; F]RZP/D`
AbX#wpp!
/**
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* @author Joa +4[Je$qYa
*/ DeQZDY //
publicinterface UserManager { J[\8:qE
E8aD[j[w
public Result listUser(Page page)throws V#~.n;d
&i*e&{L7
HibernateException; B\~(:(OPM]
#Xi9O.
} 0"mr*hyj
@8cn<+"b
i06|P I
T4;gF6(0]
78IY&q:v&0
java代码: U6YQ*%mZ_
\.=,}sV2Z
L~Xzo
/*Created on 2005-7-15*/ "~08<+
package com.adt.service.impl; c$;Cpt@-j
byk9"QeY\
import java.util.List; Se!B,'C%
0.^67'
import net.sf.hibernate.HibernateException; aOmQ<N]a
%^iBTfq2hc
import org.flyware.util.page.Page; aM\Ph&c7e'
import org.flyware.util.page.PageUtil; |O*?[|`H
5^N`~
import com.adt.bo.Result; WG&WPV/p
import com.adt.dao.UserDAO; u)Vn7zh
import com.adt.exception.ObjectNotFoundException; X/D%
cQ6
import com.adt.service.UserManager; NLev(B:OQH
t2FA|UF
/** *3y_FTh8ra
* @author Joa H<l0]-S{
*/ <07~EP
publicclass UserManagerImpl implements UserManager { 0)9n${P7d
$$T a
private UserDAO userDAO; tG0
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S6{y%K2y&
/** LiJ. /
* @param userDAO The userDAO to set. 'D^@e0.3
*/ a.XMeB
publicvoid setUserDAO(UserDAO userDAO){ jq(rnbV
this.userDAO = userDAO; u/`
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} ~AcjB(
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/* (non-Javadoc) D\z`+TyJ
* @see com.adt.service.UserManager#listUser pH396GFIW
4BJ w+EV8
(org.flyware.util.page.Page) r3~YGY
*/ ,d8*7my
public Result listUser(Page page)throws z[]8"C=
2))pB/
HibernateException, ObjectNotFoundException { n-CFB:L
int totalRecords = userDAO.getUserCount(); OlX
otp8
if(totalRecords == 0) stq%Eg?
throw new ObjectNotFoundException o^x,JT
PC& (1kJ
("userNotExist"); KWn.
page = PageUtil.createPage(page, totalRecords); :?\Je+iA
List users = userDAO.getUserByPage(page); a=*JyZ.2
returnnew Result(page, users); KtaoU2s
} F7`[r9 $
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} PLK;y
GO6uQ};
s 5F?m
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9@YhAj
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 xepp."O
SB^xq
询,接下来编写UserDAO的代码: +QEiY~i
3. UserDAO 和 UserDAOImpl: YvFt*t
java代码: }J_#N.y
#$u7:p
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/*Created on 2005-7-15*/ (q=),3/<pU
package com.adt.dao; P?<G:]W
E7@m& R
import java.util.List; B\quXE)
H) q_9<;
import org.flyware.util.page.Page; uL=FK
k}e~xbh-y
import net.sf.hibernate.HibernateException; sE\Cv2Gx
Tuy5h5
/** t0)XdIl8
* @author Joa 6FEIQ#`{
*/ {\n?IGP?wd
publicinterface UserDAO extends BaseDAO { uiaZ@
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publicList getUserByName(String name)throws N[sJ5oF
R rp-SR?O
HibernateException; #9q
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] U.*KkQ
publicint getUserCount()throws HibernateException; 1m<8M[6u
JQA]O/|N
publicList getUserByPage(Page page)throws 2h`Tn{&1/
--F6n/>
HibernateException; ZP"Xn/L
qyR}|<F8*
} J|DY
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nRheByYm
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java代码: $u::(s}
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mN1n/LNi
'~AR|8q?
/*Created on 2005-7-15*/ hfRxZ>O2
package com.adt.dao.impl; 0!q@b
yjIA`5^
import java.util.List; IkgRZ{Y
x\K,@
import org.flyware.util.page.Page; |6b&khAM
Ko %e#q-
import net.sf.hibernate.HibernateException; S i-Q'*Y=
import net.sf.hibernate.Query; 4.q^r]m*
*+j r? |
import com.adt.dao.UserDAO; MD[;Ha
;AJ6I*O@+
/** >ui;B$=
* @author Joa 4ms"mIt
*/ o}y(T07n
public class UserDAOImpl extends BaseDAOHibernateImpl oGz5ZDa#
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implements UserDAO { .hK:-q,
|}wT/3>\
/* (non-Javadoc) @8lT*O2j
* @see com.adt.dao.UserDAO#getUserByName F_nXsKem
1n~^@f#`
(java.lang.String) E[c6*I
*/ Dh)(?"^9A
publicList getUserByName(String name)throws REJHh\:.77
#bGYd}BfD
HibernateException { WUGFo$xA
String querySentence = "FROM user in class %8?XOkH)
b-YmS=*
com.adt.po.User WHERE user.name=:name"; gm7 [m}
Query query = getSession().createQuery $dF$-y<[0
Z~ u3{
(querySentence); R#HX}[Hb
query.setParameter("name", name); cs*"9nKl
return query.list(); c2:oM<6|
} +w8$-eFY
n {..Q,z
/* (non-Javadoc) G@scz!Nt
* @see com.adt.dao.UserDAO#getUserCount() FM<`\d'
*/ ?{wD%58^oG
publicint getUserCount()throws HibernateException { ?vmoRX
int count = 0; ;1q|SmF
String querySentence = "SELECT count(*) FROM YZ6"
s-
5>aK4: S/
user in class com.adt.po.User"; deCi\n
Query query = getSession().createQuery EAK[2?CY
zB'_YwW
(querySentence); Koc5~qUY]
count = ((Integer)query.iterate().next $
U-#woXa
5'n$aFqI
()).intValue(); VI?kbqjo
return count; 4X5KrecNr
} nRs:^Q~o
M[ ON2P;
/* (non-Javadoc) ^S W0+O
* @see com.adt.dao.UserDAO#getUserByPage B{>x
q$'[&&