Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 }S#.Pw%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根
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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 tH_#q"@)
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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 \W=
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分页支持类: WZm^:,
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java代码: HhqqJEp0
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package com.javaeye.common.util; ,7j`5iq[m
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import java.util.List; 3_h%g$04s
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publicclass PaginationSupport { *kKGsy
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publicfinalstaticint PAGESIZE = 30; E_H1X'|qS4
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privateint pageSize = PAGESIZE; l w%fY{
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privateList items; A%GJ|h,i
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privateint totalCount; )j9FB
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privateint[] indexes = newint[0]; %kc g#p+tE
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privateint startIndex = 0; qnA:[H;F
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public PaginationSupport(List items, int IK W!P1
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totalCount){ :EO}uP2
setPageSize(PAGESIZE); #ERn 8k
setTotalCount(totalCount); P\M+ZA ;
setItems(items); p0tv@8C>
setStartIndex(0); @i`gR%
} {$EXI]f
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public PaginationSupport(List items, int r]E$uq
bR
q@\_q!
totalCount, int startIndex){ JJ+<?CeHD
setPageSize(PAGESIZE); Y{O&-5H^|
setTotalCount(totalCount); g@U#Y#b@"
setItems(items); D3K`b4YV
setStartIndex(startIndex); <N*>9S,}
} >ciq4H43Q|
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public PaginationSupport(List items, int -m@s
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totalCount, int pageSize, int startIndex){ yp4G"\hN9
setPageSize(pageSize); ryT8*}o
setTotalCount(totalCount); ~H$XSNPi
setItems(items); x'KsQlI/
setStartIndex(startIndex); eeDhTw9
} 6,7omYof
roA1=G\Q
publicList getItems(){ U;nC)'~YW9
return items; &Ch)SD
} BmM,vllO
L!p|RKz9X
publicvoid setItems(List items){ |")x1'M
this.items = items; &-*nr/xT
} <2Q@^
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publicint getPageSize(){ gP<_DEd^`
return pageSize; saT9%?4-
} Cb6MD
[s/@z*,M1
publicvoid setPageSize(int pageSize){ r#Mx~Zg~
this.pageSize = pageSize; % n{W
} wI4;/w>
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publicint getTotalCount(){ Q*8-d9C
return totalCount; bxN;"{>Xz
} 3wE8y&
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publicvoid setTotalCount(int totalCount){ Z C93C7lJ
if(totalCount > 0){ .#@D n(
this.totalCount = totalCount; *I67SBt
int count = totalCount / nADd,|xD3
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pageSize;
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if(totalCount % pageSize > 0) ]cr;PRyv
count++; (HI%C@e9
indexes = newint[count]; k~#|8eLv
for(int i = 0; i < count; i++){ Dkb&/k:)
indexes = pageSize * @QG1\W'
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i; KV_Ga8hs
} }#8uXA
}else{ ?~.&Y
this.totalCount = 0; 9ojhI=:
} bY~ v0kg
} f>dkT'4
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publicint[] getIndexes(){ 1VFqT'
return indexes; |esjhf}H>v
} [QbXj0en$
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publicvoid setIndexes(int[] indexes){ r%pFq1/'!
this.indexes = indexes; $0}bi:7
} ^ kvH/ Y&
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publicint getStartIndex(){ h<;[P?z
return startIndex; sK0VT"7K
} ?MM3LA! <
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publicvoid setStartIndex(int startIndex){ SAh054/St
if(totalCount <= 0) L_"(A
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this.startIndex = 0; 3|Sy'J0'K
elseif(startIndex >= totalCount) lzG;F]
this.startIndex = indexes K<6x4ha
bU ]N^og^
[indexes.length - 1]; lmKq xs4
elseif(startIndex < 0) *"FLkC4
this.startIndex = 0; MuV0;K\
else{ b0Ov+ )7#
this.startIndex = indexes Us,[x Q
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[startIndex / pageSize]; G*i# \
} ,'CWt]OS'
} n/oipiYx
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publicint getNextIndex(){ _SC
int nextIndex = getStartIndex() + t!~YO'<dS
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pageSize; ](>7h_2B
if(nextIndex >= totalCount) )_*a7N!
return getStartIndex(); eM=) >zl
else =+}}Sv2
return nextIndex; D4Y!,7WEVt
} RyOT[J
nP\V1pgA
publicint getPreviousIndex(){ (GEi<\16[
int previousIndex = getStartIndex() - yC0f/O
%}MA5 t]o
pageSize; e9@fQ
if(previousIndex < 0) OZ!$%.?l
return0; `bZU&A(`Be
else ;q,)NAr&
return previousIndex; ccn`f]5w
} ;5Vk01R
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} i\Pr3
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抽象业务类 Uty(sDtu
java代码: vbA7I<;
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/** J`+`Kq1T
* Created on 2005-7-12 K rr?`n
*/ n`m_S
package com.javaeye.common.business; adO!Gs9f?
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import java.io.Serializable; tC?Aso
import java.util.List; Lk`k>Nn)
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import org.hibernate.Criteria; VX!Y`y^a
import org.hibernate.HibernateException; )-.Cne;n
import org.hibernate.Session; 3j+=3n,
import org.hibernate.criterion.DetachedCriteria; <RoX| zJw
import org.hibernate.criterion.Projections; ^3WIl]
import :!I)r$
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org.springframework.orm.hibernate3.HibernateCallback; =nvAOvP{?
import Q.9Ph
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org.springframework.orm.hibernate3.support.HibernateDaoS x0u?*5-t
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upport; ^p"4)6p-W
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import com.javaeye.common.util.PaginationSupport; jMf 7J
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public abstract class AbstractManager extends A]Q1&qM%
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HibernateDaoSupport { .*EOVo9S
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privateboolean cacheQueries = false; ^_*jp[!`b$
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privateString queryCacheRegion; 2vqmsl?
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publicvoid setCacheQueries(boolean CJMaltPp&
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cacheQueries){ Z:_m}Ya|
this.cacheQueries = cacheQueries; (30<oE{
} >/TB_ykb
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publicvoid setQueryCacheRegion(String r@*=|0(OrK
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queryCacheRegion){ wJ80};!
this.queryCacheRegion = ]z-']R;
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queryCacheRegion; vp\PYg;x
} 1DEO3p
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publicvoid save(finalObject entity){ Sni&?tcY
getHibernateTemplate().save(entity); ";wyNpb(
} G 2%
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publicvoid persist(finalObject entity){ v}7@CP]nV
getHibernateTemplate().save(entity); P$p@5 hl
} TK;\_yN
jd ["eI
publicvoid update(finalObject entity){ \We"?1^
getHibernateTemplate().update(entity); V/aQ*V{
} 0s860Kn
*'Z-OY<V
publicvoid delete(finalObject entity){ G_V.H\w
getHibernateTemplate().delete(entity); !"g=&Uy&
} E4Y"X
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publicObject load(finalClass entity, n_<mPU
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finalSerializable id){ y._'K+nl
return getHibernateTemplate().load \Os:6U=X-
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(entity, id); ^Vag1(hdq
} |.1qy,|!X
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publicObject get(finalClass entity, 0(wf{5
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finalSerializable id){ (FM4 ^#6
return getHibernateTemplate().get %/P=m-K
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(entity, id); M[A-1]'
} ;!'qtw"CB
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publicList findAll(finalClass entity){ 1+R:3(AC
return getHibernateTemplate().find("from 'KSa8;:=C
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" + entity.getName()); 8|w-XR
} %>i@F=O2<
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publicList findByNamedQuery(finalString e[s5N:IUd3
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namedQuery){ W3^.5I
return getHibernateTemplate ]K7`-p~T
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().findByNamedQuery(namedQuery); p:B
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} m)r]F#@/
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publicList findByNamedQuery(finalString query, ` "B^{o
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finalObject parameter){ RYt6=R+f
return getHibernateTemplate }f0u5:;Zth
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().findByNamedQuery(query, parameter); =Ci13< KQ
} )i @1XH"D
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publicList findByNamedQuery(finalString query, 9/G!0uE
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finalObject[] parameters){ NS Np
return getHibernateTemplate `0?^[;[u[
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().findByNamedQuery(query, parameters); E[UO5X
} mk\i}U>`
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publicList find(finalString query){ JPsSw
return getHibernateTemplate().find ^T{8uJ'kn
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(query); [7RheXO<
} QhCY}Q?X
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publicList find(finalString query, finalObject FOSbe]
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parameter){ rCE;'? Y
return getHibernateTemplate().find -1CEr_(P^
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(query, parameter); YN^T$,*
} \e|U9;Mf
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public PaginationSupport findPageByCriteria 9^!wUwB
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(final DetachedCriteria detachedCriteria){ s@s/'^`
return findPageByCriteria T/5"}P`
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); sQtf,e|p
} 5qRc4d'
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public PaginationSupport findPageByCriteria yb?{LL-uy
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(final DetachedCriteria detachedCriteria, finalint -;>#3O-
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startIndex){ .'/l'>
return findPageByCriteria `L\)ahM
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(detachedCriteria, PaginationSupport.PAGESIZE, 7]s%rya
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startIndex); V&[eSVY?
} q@kOTkHv)
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public PaginationSupport findPageByCriteria l{5O5%\,
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(final DetachedCriteria detachedCriteria, finalint %`+'v_iu
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pageSize, 8*s7m
finalint startIndex){ 5m7b\Mak
return(PaginationSupport) DjwQ`MA
*b"CPg/\
getHibernateTemplate().execute(new HibernateCallback(){ 6IP$n($2
publicObject doInHibernate CZ3].DA|z
IqUp4}
(Session session)throws HibernateException {
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Criteria criteria = rY,PSK/j
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detachedCriteria.getExecutableCriteria(session); ZXt?[Ll
int totalCount = v"RiPHLT
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((Integer) criteria.setProjection(Projections.rowCount :<GfET Is
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()).uniqueResult()).intValue(); ,[`$JNc
criteria.setProjection <'&F;5F3V
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(null); -;pOh;WG
List items = 0pN{y}x,
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criteria.setFirstResult(startIndex).setMaxResults (A{NF(
i8~$o:&HT
(pageSize).list(); OOB^gf}$'
PaginationSupport ps = >SDpuG&>
PLdn#S}.
new PaginationSupport(items, totalCount, pageSize, l>&sIX
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startIndex); <9ifPSvJ
return ps; qC@Ar)T
} EGS%C%>l/o
}, true); S|K}k:v8
} maC>LBa2/
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public List findAllByCriteria(final f=`33m5
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DetachedCriteria detachedCriteria){ vM4<d>
return(List) getHibernateTemplate d?hz LX
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().execute(new HibernateCallback(){ 3KcaT5(&
publicObject doInHibernate 3t(c_:[%
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(Session session)throws HibernateException { X:=c5*0e
Criteria criteria = B QjGv?p0s
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detachedCriteria.getExecutableCriteria(session); 7=k^M, a
return criteria.list(); 'UfeluMd
} S "
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}, true); -9o{vmB{
} ]ii+S"U3
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public int getCountByCriteria(final >ttuum12w
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DetachedCriteria detachedCriteria){ 1`-r#-MGG
Integer count = (Integer) 9%!dNnUk
js <Ww$zFW
getHibernateTemplate().execute(new HibernateCallback(){ SUE
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publicObject doInHibernate w> 979g
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(Session session)throws HibernateException { 6E^~n
Criteria criteria = y=H@6$2EQ
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detachedCriteria.getExecutableCriteria(session); keCRvl Z4
return DWf$X1M
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criteria.setProjection(Projections.rowCount S>f&6ZDNY(
>Ko[Xb-8^_
()).uniqueResult(); 9_huI'"p
} |y1;&<
}, true); g7V_[R(6
return count.intValue(); bQQVj?8jp
} 'HaD~pa
} ~&g a1r2v?
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2 ZG@!Y|
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用户在web层构造查询条件detachedCriteria,和可选的 !B^K[2`)N
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f!
startIndex,调用业务bean的相应findByCriteria方法,返回一个 YQVcECj
-=5)NH
t
PaginationSupport的实例ps。 8^ #mvHah
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ps.getItems()得到已分页好的结果集 `X8@/wf#
ps.getIndexes()得到分页索引的数组 DW2>&|
ps.getTotalCount()得到总结果数 ! OE*z $\
ps.getStartIndex()当前分页索引 fx?$9(r,
ps.getNextIndex()下一页索引 )=_ycf^MC
ps.getPreviousIndex()上一页索引 M-MKk:o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ;l!`C' :'
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 J YmAn?o-
o"q+,"QL
一下代码重构了。 +^ yq;z
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我把原本我的做法也提供出来供大家讨论吧: 3V;gW%>
.+.j*>q>u
首先,为了实现分页查询,我封装了一个Page类: 4Z5#F]OA7
java代码: R7_VXvm>z
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/*Created on 2005-4-14*/ reiU%C
package org.flyware.util.page; k`VM2+9h'^
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/** %oof}=MxCL
* @author Joa `f`TS#V
* q``wt
*/ l] !B#{
publicclass Page { lU.Kc
bB6[Xj{
/** imply if the page has previous page */ V3s L;
privateboolean hasPrePage; ,sQ93(Vo
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/** imply if the page has next page */ 7y<1LQ;}
privateboolean hasNextPage; K4%/!`
Poy^RpnX
/** the number of every page */ Zi
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privateint everyPage; 2F+gF~znQ
@,OT/egF4:
/** the total page number */ SW 8x]B
privateint totalPage; ]r/^9XaqtA
W!la -n
/** the number of current page */ <+U|dX
privateint currentPage; ^DAu5 |--R
q mQfLz7&x
/** the begin index of the records by the current m&Y i!7@(
WlVl[/qt
query */ p{tK_ZBy]c
privateint beginIndex; ocQWQ
.#w6%c@
1{PG>W
/** The default constructor */ vmZ"o9-{#X
public Page(){ !iu5OX7K|
-j`LhS~|
} _elX<o4
_GA$6#]
/** construct the page by everyPage Akk
3 Qx
* @param everyPage M0'v&g
* */ ZFn(x*L
public Page(int everyPage){ = !2NU
this.everyPage = everyPage; PlxIfL
} :8f[|XR4\N
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/** The whole constructor */ Jfhk@27T
public Page(boolean hasPrePage, boolean hasNextPage, 4_=Ja2v8;`
&"E
lm
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int everyPage, int totalPage, >FF5x#^&c
int currentPage, int beginIndex){ "VUYh$=[
this.hasPrePage = hasPrePage; w4};q%OBj
this.hasNextPage = hasNextPage; dF@)M
this.everyPage = everyPage; YZwaD b
this.totalPage = totalPage; [
!%R#+o=F
this.currentPage = currentPage; Ib`-pRU;
this.beginIndex = beginIndex; }VCI=?-
} pmc=NTr&<
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/**
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* @return (/{aJV
* Returns the beginIndex. 6^F'|Wh
*/ xTV{^=\rS
publicint getBeginIndex(){ '+y_\
return beginIndex; <=um1P3X
} zc+@lJy
Mt>oI SN&d
/** yW7'?
* @param beginIndex J./d!an
* The beginIndex to set. 2.I^Xf2
*/ }F=^O[
publicvoid setBeginIndex(int beginIndex){ PX
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this.beginIndex = beginIndex; a:rX9-**
} @tT-JwU
%:9oDK
/** ^rAa"p 9
* @return &l2TeC@;
* Returns the currentPage. U>qHn'M
*/ tD=@ SX'Y
publicint getCurrentPage(){ mLbN/M
return currentPage; `#s#it'y
} #@.-B,]
:' #\
/** nhT(P`6
* @param currentPage m?CZQq,
* The currentPage to set. P Ru&3BP
*/ : 3ZYJW1
publicvoid setCurrentPage(int currentPage){ wTq{ sW&
this.currentPage = currentPage; " {dek
} Gpj* V|J
[:;# ]?
/** ;@mRo`D`
* @return Zk-~ar
* Returns the everyPage. (U1]:tZ<.
*/ - xm{&0e)
publicint getEveryPage(){ :%rS
=f
return everyPage; cWAtju?L;
} S7iDTG_@t
C}}/)BYi
/** ,T{<vRj7_
* @param everyPage wVl+]zB
* The everyPage to set. a>mMvc"
*/ U7$WiPTNL9
publicvoid setEveryPage(int everyPage){ x i~uv?f
this.everyPage = everyPage; -b;|q.!
} /#LW"4;*
]c)_&{:V
/** pV[''
* @return Td\o9
* Returns the hasNextPage. {d3<W N
*/ 0$ .m_0H
publicboolean getHasNextPage(){ -1|iz2^N
return hasNextPage; AIijCL
} N5U)*U'-u
-~f511<
/** ?*"srE,#JX
* @param hasNextPage G'z{b$?/[
* The hasNextPage to set. i{c@S:&@^
*/ m6mwyom.
publicvoid setHasNextPage(boolean hasNextPage){ _D7 ]-3uC!
this.hasNextPage = hasNextPage; px''.8
} ]88];?KS}
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/** Q%S9fq,q
* @return ksR1kvTm
* Returns the hasPrePage. *>8ce-PV
*/ ?DV5y|}pj
publicboolean getHasPrePage(){ RIn9(r
return hasPrePage; Ard]147
} Y4.Eq+$gh
[/M^[p
/** E ]9\R
* @param hasPrePage ow'Vz
Ay-
* The hasPrePage to set. 'T=~jA7SkT
*/ }R4c
publicvoid setHasPrePage(boolean hasPrePage){ AV8T
this.hasPrePage = hasPrePage; a,t``'c;
} nKr9#JebRC
nz.{P@[Qk
/** Q _iO(qu
6
* @return Returns the totalPage. UYP9c}_,4
* Q^Ql\
*/ J8a*s`ik
publicint getTotalPage(){ az;Q"V'6
return totalPage; -f1k0QwL
} T'-FV
1nknSw#
/** SlLw{Yb7\.
* @param totalPage g9fq5E<G
* The totalPage to set. 4\ c,)U}
*/ t>)45<PEw
publicvoid setTotalPage(int totalPage){ b,TiMf9},h
this.totalPage = totalPage; )jrT6x^IB
} YV4#%I!<
Uh1NO&i.W
} 3oZ=k]\
.9[45][FK
T^<>Xiam
m(iR|Zx
FXdD4 X)
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 xda;
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个PageUtil,负责对Page对象进行构造: RZpcXv
java代码: cXMhq<GkAA
rx"s!y{!-
;^Sr"v6r>u
/*Created on 2005-4-14*/ ,B<l
package org.flyware.util.page; Qcjc,
-m=
8&B
import org.apache.commons.logging.Log; HBE.F&C88
import org.apache.commons.logging.LogFactory; }V;+l8
"&Dx=Yf
/** B\*@krI@
* @author Joa
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* ]&~]#vB#
*/ e,_-Je
publicclass PageUtil { x_!0.SU
/%aiEhL
privatestaticfinal Log logger = LogFactory.getLog { x0 t
3=Ec"
(PageUtil.class); ; |/leu8
V(MFna)
/** ^taBG3P
* Use the origin page to create a new page w6dFb6~R
* @param page |]Z:&[D]i
* @param totalRecords FOwDp0
* @return )Rat0$6
*/ %n%xR%|
publicstatic Page createPage(Page page, int 8mLP5s!7
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totalRecords){ -V"22sR]
return createPage(page.getEveryPage(), -7uwOr
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page.getCurrentPage(), totalRecords); lDC$F N
} I|-p3g8\
BG^C9*ZuP
/** C'=k<-
* the basic page utils not including exception j6~nE'sQ
p47S^gW
handler !J*,)kRN
* @param everyPage qrvsjYi*w
* @param currentPage -5>-%13
* @param totalRecords '/Bidb?
* @return page rdnno
*/ 6J~12TU,
publicstatic Page createPage(int everyPage, int Ko&hj XHx
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currentPage, int totalRecords){ m+{K^kr[
everyPage = getEveryPage(everyPage); &AuF]VT
currentPage = getCurrentPage(currentPage); ~m1P_`T
int beginIndex = getBeginIndex(everyPage, DcIvhB p
t#nn@Yf
currentPage); &bqT/H18
int totalPage = getTotalPage(everyPage, 2>-S-;i
f\;65k_jq
totalRecords); $wYtyN[
boolean hasNextPage = hasNextPage(currentPage, ]Q
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totalPage); _UE)*l m+
boolean hasPrePage = hasPrePage(currentPage); %;D+k
$qF0ltUQ
returnnew Page(hasPrePage, hasNextPage, 0w'j+
everyPage, totalPage, Iu~\L0R427
currentPage, Sx*oo{Kk%
%xlqF<
beginIndex); G5dO 3lwq
} $rXh0g
b,P ]9$Ut
privatestaticint getEveryPage(int everyPage){ s%iOUL2/
return everyPage == 0 ? 10 : everyPage; '`Bm'Dd
} SxyONp.$\
,U *)2`[
privatestaticint getCurrentPage(int currentPage){ 4RKW
return currentPage == 0 ? 1 : currentPage; ;)Kh;;e
} N3t0-6$_
PqNFyQkl
privatestaticint getBeginIndex(int everyPage, int +,:^5{9{
iFSJL,QZ3
currentPage){ ^1:U'jIXO
return(currentPage - 1) * everyPage; %puLr'Y
} jUj<~:Q}3o
D3Jr3
%>
privatestaticint getTotalPage(int everyPage, int A392=:N+Q
UV}73Sp
totalRecords){ at!Y3VywG
int totalPage = 0; }],Z;:
d;Hn#2C
if(totalRecords % everyPage == 0) lcON+j
totalPage = totalRecords / everyPage; 9 7%0;a8
else UE _fpq
totalPage = totalRecords / everyPage + 1 ; oRN-xng
!>x|7
return totalPage; `=#01YX[0
} +u@aJ_^
2:}fe}
privatestaticboolean hasPrePage(int currentPage){ NT%W;)6m9
return currentPage == 1 ? false : true; QU{Ech'
} 6*9}4`
Z'pQ^MO
privatestaticboolean hasNextPage(int currentPage, Xf=XBoN|
"O+5R(XT
int totalPage){ PIA)d-Z
return currentPage == totalPage || totalPage == O#nR>1h
&m3.h!dq
0 ? false : true; )T907I|
} *fO3]+)d+
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QYXx:nIrg
} RO\gax
C8@TZ[w
QVZD/shq
Uu6L~iB
_|<d5TI
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。 M_B:{%4
(VyNvB
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 2^~<("+w
t<uYM
做法如下: x+? 9C
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ci,+Bjc
[\)oo
的信息,和一个结果集List: q<e&0u4
java代码: rh2LGuo4m
@#+jMV$g
9L%I<5i
/*Created on 2005-6-13*/ {s,+^7
package com.adt.bo; -0o[f53}p
F9c`({6k
import java.util.List; /4=-b_2Y~
"re-@Baw
import org.flyware.util.page.Page; PDx)S7+w[
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/** C>^D*C(
* @author Joa P#kGX(G9!
*/ X{Yw+F,j
publicclass Result { NX* O_/
t$&Qv)
private Page page; kg5ev8
Itm8b4e9;
private List content; <Pqv;WI|R
5`^o1nGO'
/** 7&}P{<}o^
* The default constructor !}TMiCK
*/ HCA{pR`
public Result(){ p?(L'q"WK
super(); }pNX@C#De
} Ftb%{[0}u3
Dkw%`(Oh/,
/** hPm>tV2X
* The constructor using fields 2)iD4G`
* *xRc *
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* @param page jX=lAs~6
* @param content *ck}|RhR
*/ =Cf]
public Result(Page page, List content){ `%K`gYhG1
this.page = page; qX:B4,|ck
this.content = content; U SOKDDm
} 2f, B$-#
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/** MlO-+}`_+
* @return Returns the content. ;uI~BV*3
*/ uPyVF-i
publicList getContent(){ A//?6OJx?
return content; N?r>%4
} _v5t<_^N
q1Qje%9@t
/** ,+/zH'U}
* @return Returns the page. n"{X!(RIcx
*/ U)jUq_LX
public Page getPage(){ >O{7/)gS^
return page; 8m=Z|"H@
} F%.xuL W
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/** ND]S(C"?
* @param content x2wg^$F*oO
* The content to set. 6k0^ x Q
*/ /"AvOh*
public void setContent(List content){ Y)HbxFF`/
this.content = content; '8Wv.X0`
} <HoAj"xf
i s"vekC
/** eMMx8E)B
* @param page Rq)BssdF
* The page to set. cf8-]G?tK
*/ q=c/B(II!
publicvoid setPage(Page page){ O&?.&h
this.page = page; gp
} lglYJ,
} 9BON.` |_
\P?ToTTV
hb^!LtF#Y
?X_V#8JK
# mT]j""
2. 编写业务逻辑接口,并实现它(UserManager, 1M5 -pZ[D
1p\Ak
UserManagerImpl) UVX"fZ)
java代码: SE `l(-tL
Q7Ij4
Wc'Ehyi;
/*Created on 2005-7-15*/ :$H!@n*/R
package com.adt.service; #s"B-sWE
S ~|.&0"\
import net.sf.hibernate.HibernateException; !oMt_k X
gbGTG(:1S
import org.flyware.util.page.Page; b~Z=:'m8
} p'8w\C$
import com.adt.bo.Result; ,b'4CF
"bX4Q4Dq
/** <MZi<Z`
* @author Joa b7$}JCn
*/ %g^"]
publicinterface UserManager { h5onRa*7
{+=i?
public Result listUser(Page page)throws ROoE%%8I
*SZ>upg
HibernateException; a-PGW2G
"{F;M{h$},
} &BgU:R,
\Hum }0[
YNM\pX'
9~Xg#{
?)cJZ>$!w
java代码: 2V$9ei6
JuJ5qIal
|R~;&x:
/*Created on 2005-7-15*/ *Q/E~4AW|t
package com.adt.service.impl; hEOJb
@:R
Nmf#`+7gCI
import java.util.List; jOl 1_
4A~)b"j5
import net.sf.hibernate.HibernateException; 6y@<?08Q
b\L)m (
import org.flyware.util.page.Page; @,vv\M0)p
import org.flyware.util.page.PageUtil; &7F&}7*c
E& ]_U$
import com.adt.bo.Result; Gg+YfY_
import com.adt.dao.UserDAO; liG~y|
import com.adt.exception.ObjectNotFoundException; Qa?QbHc
import com.adt.service.UserManager; -s~p}CQ.
M9g1d7%
/** }85#[~m'
* @author Joa a}D&$yz2
*/ KgU[
publicclass UserManagerImpl implements UserManager { `q1}6U/k
mt .,4
private UserDAO userDAO; riEqW}{
Ja=N@&Z#
/** %0(>!SY
* @param userDAO The userDAO to set. !L$oAqW
*/ *<3iEeO/R
publicvoid setUserDAO(UserDAO userDAO){ EQ~I'#m7
this.userDAO = userDAO; 1
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} A'v[SUW'm
|vN$"mp^a
/* (non-Javadoc) Sh47c4{
* @see com.adt.service.UserManager#listUser A>y#}^l]
@f'AWeJ2
(org.flyware.util.page.Page) OAyE/Q|
*/ JgZdS-~
public Result listUser(Page page)throws %,E7vYjT%
v_.j/2U
HibernateException, ObjectNotFoundException { zN/Gy}
int totalRecords = userDAO.getUserCount(); #|D:f~"d3
if(totalRecords == 0) w5=EtKTi
throw new ObjectNotFoundException KKMWD\
],#ZPUn
("userNotExist"); ri;r7Y9V9`
page = PageUtil.createPage(page, totalRecords); QD6Z=>?S
List users = userDAO.getUserByPage(page); ~l@%=/m
returnnew Result(page, users); $o::PDQ?
} ,P1G?,y
"N]WL5$i
} _4A&%>
C(ZcR_+r$,
lHRK'?Q
9Z}S]-u/
nFSG<#x\
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %hrsE5k^,
HJ(=?TU
询,接下来编写UserDAO的代码: ;vZ*,q6
3. UserDAO 和 UserDAOImpl: $Jt8d|UP
java代码: (rMTW+,
7jD@Gp`" 3
gS0,')w
/*Created on 2005-7-15*/ H==X0
package com.adt.dao; 9 ?[4i'
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import java.util.List; (p'/p
[ )B@
import org.flyware.util.page.Page; 7Co3P@@
AZ]Z,s6
import net.sf.hibernate.HibernateException; P'KY.TjWb
an #jZ[
/** p PU 2ar
* @author Joa
}qTv&Z3$
*/ U5T^S
publicinterface UserDAO extends BaseDAO { sT@u3^>
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publicList getUserByName(String name)throws *
N2#{eF&]
&FT5w T
HibernateException; zV9
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publicint getUserCount()throws HibernateException; $v2S;UB v*
pU[a[
publicList getUserByPage(Page page)throws 6uv'r;U]
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HibernateException; w/)e2CH
jauc*347
} UzP@{?
+;{rU&
f[wjur
AqTR.}H
;5zjd,
java代码: F=P+;%.
:K
a^
W\ZV0T;<]
/*Created on 2005-7-15*/ il 8A&`%
package com.adt.dao.impl; E0WrpGZ
bUEt0wRR
import java.util.List; w%!k?t,*]
@8}-0c
import org.flyware.util.page.Page; U/v"?pg[
5G
dY7t_1
import net.sf.hibernate.HibernateException; OdtbVF~
import net.sf.hibernate.Query; bF8xQ<i~Y
4 @ydK
import com.adt.dao.UserDAO; &z1|
4OB~h]Vc
/** N69eIdl
* @author Joa c+YYM
:S
*/ g6k&c"%IQ(
public class UserDAOImpl extends BaseDAOHibernateImpl N23+1 h
Gh chfI.
implements UserDAO { Dg];(c+/
-O5(%
/* (non-Javadoc) /I`!iK
* @see com.adt.dao.UserDAO#getUserByName %s&E-*X
8/kx 3
(java.lang.String) %^)Ja EUC
*/ l%Fse&4\
publicList getUserByName(String name)throws u:qD*zOq
;^*+:e
HibernateException { r5fz6"
String querySentence = "FROM user in class AU${0#WV_
]CtoK%k
com.adt.po.User WHERE user.name=:name"; bl+@}+A
Query query = getSession().createQuery Q'%5"&XFD
,EGD8$RA]
(querySentence); /d]V{I~6
query.setParameter("name", name); 5;i!PuL
return query.list(); u3v6$CD?
} ytcG6WN3
6{,K7FL
/* (non-Javadoc) 6@Z'fT4
* @see com.adt.dao.UserDAO#getUserCount() h(N9RJ}
*/ JWm^RQ
publicint getUserCount()throws HibernateException { Rs(CrB/M
int count = 0; o\:f9JL
String querySentence = "SELECT count(*) FROM O+UV\
TG%hy"k
user in class com.adt.po.User"; Osvz 3UMY3
Query query = getSession().createQuery gPhw.e""
)su
<Ji*
(querySentence); "8iyMP%8
count = ((Integer)query.iterate().next &s}@7htE
(8eNZ*+mO
()).intValue(); ^J}$y7
return count; XCi]()TZ_
} ~)_ ?:.Da
nAba
=iW
/* (non-Javadoc) '|A5a+[
* @see com.adt.dao.UserDAO#getUserByPage y:6'&`L
1j)!d$8
(org.flyware.util.page.Page) ;h(;(
*/ -L4G WJ~.-
publicList getUserByPage(Page page)throws 6x zR*~7
TWR#MVMI
HibernateException { my #u^O;
String querySentence = "FROM user in class SAo\H
R_*D7|v
com.adt.po.User"; 2;(iTPz +
Query query = getSession().createQuery uW--
nXMs
sq6% =(q(?
(querySentence); m+8b2H:V
query.setFirstResult(page.getBeginIndex()) MHT,rqG
.setMaxResults(page.getEveryPage()); Kac j
return query.list(); )PoI~km
} SUi1*S
SlJ/OcAf#
} %LZM5Z^
V-U
^O45
f;XsShxr
;gu>;_
[W|7r
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至此,一个完整的分页程序完成。前台的只需要调用 ?;#3U5$v
J]^gF|
userManager.listUser(page)即可得到一个Page对象和结果集对象 }br<2?y,
3%4Mq6Q`
的综合体,而传入的参数page对象则可以由前台传入,如果用 e]B<