Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *y[PNqyd
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }]P4-KqI
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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 5__+_hO
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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 +~Cy$MCX
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。 e59dVFug.U
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分页支持类: t-%Q`V=[
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java代码: ^S)TO}e
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package com.javaeye.common.util; BF|(!8S$U
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import java.util.List; {-zMHVw=}
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publicclass PaginationSupport { }`_@'4:t
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publicfinalstaticint PAGESIZE = 30; iyx>q!P
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privateint pageSize = PAGESIZE; ;bu#8,
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privateList items; W\*-xf|"d
sE(HZR1
privateint totalCount; 8Ad606
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privateint[] indexes = newint[0]; Q<tu) Qo
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privateint startIndex = 0; Z*{]
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public PaginationSupport(List items, int Ru!He,k7
@pV5}N[]
totalCount){ z(RL<N%
setPageSize(PAGESIZE); ~K_Uq*dCE
setTotalCount(totalCount); <{(/E0~V/<
setItems(items); &6 -k#r
setStartIndex(0); 4tA_YIv
} Die-@z|Y
W><Zn=G4)b
public PaginationSupport(List items, int tEd.'D8 s
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totalCount, int startIndex){ k4J8O3E
setPageSize(PAGESIZE); 5R$G(Ap_
setTotalCount(totalCount); i yYJR
setItems(items); mbl]>JsQD
setStartIndex(startIndex); F#|O@.tDG
} 1xyU
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0
public PaginationSupport(List items, int $L4/I !Yf
5vzceQE}
totalCount, int pageSize, int startIndex){ E&$_`m;
setPageSize(pageSize); v'2[[u{7*
setTotalCount(totalCount); 4\t1mocCSN
setItems(items); W~T}@T:EN
setStartIndex(startIndex); #PvB/3
} AZ |yX
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publicList getItems(){ &>WWzikB*
return items; 2Tav;LKX
} pVp:@0h
`i~ Y Fr
publicvoid setItems(List items){ .@ C{3$,VG
this.items = items; UUo;`rkT
} Cm$1$?J
+#@"*yj3
publicint getPageSize(){ }0hL~i
return pageSize; N<|$h5isq
} 2g{)AtK$#
@*N)i?>
publicvoid setPageSize(int pageSize){ ]Hj<IvG
this.pageSize = pageSize; oz'\q0
} Gnm4gF!BI
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publicint getTotalCount(){ BDY}*cX
return totalCount; >Y 1{rSk
} iJFs0?*
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publicvoid setTotalCount(int totalCount){ yj6@7@l>A
if(totalCount > 0){ X#a`K]!B
this.totalCount = totalCount; 57{oh")
int count = totalCount / ^62|d
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pageSize; (oK^c-x
if(totalCount % pageSize > 0) iyZZ}M
count++; r9 y.i(j
indexes = newint[count]; kyh_9K1
for(int i = 0; i < count; i++){ u
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indexes = pageSize * TfxwVPX
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i; .N4
} .UCt|> $
}else{ ER2GjZa\z
this.totalCount = 0; O[17";P
} s}&bJ"!Z
} RIM`omM
g o5]<4`r
publicint[] getIndexes(){ F-(dRSDNM
return indexes; T`/IO.2
} SDG-~(Y
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publicvoid setIndexes(int[] indexes){ Uv_N x10
this.indexes = indexes; PMs z`
} \ A1uhHP!
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publicint getStartIndex(){ 6}~pq1IF{
return startIndex; >e5 *prx+
} !U_K&f
-
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publicvoid setStartIndex(int startIndex){ gMWBu~;!
if(totalCount <= 0) .o%^'m"=D[
this.startIndex = 0; )o1eWL}
elseif(startIndex >= totalCount) j83? m
this.startIndex = indexes {eJt,[Y *
a~h:qpgc
[indexes.length - 1]; bo"%0?3n
elseif(startIndex < 0) 5\mTr)\R
this.startIndex = 0; n;HHogA
else{ r,SnXjp@
this.startIndex = indexes wCMQPt)VS
+`mGK:>
[startIndex / pageSize]; ymY1o$qWB}
} =+5,B\~q@C
} ,?UM;^
75!9FqMZ}
publicint getNextIndex(){ -${DW^txMZ
int nextIndex = getStartIndex() + 6[qA`x#
1L7{p>;-dO
pageSize; C<^YVeG
if(nextIndex >= totalCount) D\~zS`}
return getStartIndex(); -kz4FS
else EO|:FcW
return nextIndex; =*BIB5
} PW(\4Q\
0oA{Jix
publicint getPreviousIndex(){ qM4c]YIaSl
int previousIndex = getStartIndex() - S|V4[ssB
[./6At&|
pageSize; }/dRU${!
if(previousIndex < 0) ubsSa}$q
return0; #BVtL :x@
else $aCd/&
return previousIndex; 3H\w2V
} p1pQU={<
@K223?c8l
} [$(%dV6O
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抽象业务类 !"Yj|Nu6
java代码: |!|^ v
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/** k;PAh>8
* Created on 2005-7-12 2A`A\19t
*/ ^Jp&H\gI.
package com.javaeye.common.business; (;x3} ]
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import java.io.Serializable; MvLs%GE%
import java.util.List; t9
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import org.hibernate.Criteria; =.<@`1
import org.hibernate.HibernateException; WS-dS6Q}
import org.hibernate.Session; 0|xIBg)
import org.hibernate.criterion.DetachedCriteria; p?[Tm*r
import org.hibernate.criterion.Projections; (GnuWc\p
import `J<*9dq%
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org.springframework.orm.hibernate3.HibernateCallback; 2I3h
MD0
import \?>Hu
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org.springframework.orm.hibernate3.support.HibernateDaoS 'X).y1'
0<"k8
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upport; <tpmUA[]
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import com.javaeye.common.util.PaginationSupport; c5q9LQ/
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public abstract class AbstractManager extends yw[ #
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HibernateDaoSupport { :a8 YV!X
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privateboolean cacheQueries = false; t-
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privateString queryCacheRegion; H~eRT1
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publicvoid setCacheQueries(boolean o56`
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cacheQueries){ -50HB`t
this.cacheQueries = cacheQueries; *D4hq=
} V6$xcAE"</
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publicvoid setQueryCacheRegion(String m42T9wSsx
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queryCacheRegion){ iUMY!eqp
this.queryCacheRegion = K/m3
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queryCacheRegion; ?7:KphFX)
} mS>xGtD&K
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publicvoid save(finalObject entity){ :.(;<b<\
getHibernateTemplate().save(entity); OJT1d-5p
} YzosZ! L!<
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publicvoid persist(finalObject entity){ { pu85'DV
getHibernateTemplate().save(entity); ERwHLA
} V^y^
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publicvoid update(finalObject entity){ g71[6<D
getHibernateTemplate().update(entity); ~/NKw:
} ZZQG?("S'
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publicvoid delete(finalObject entity){ hLJM%on
getHibernateTemplate().delete(entity); _AV1WS;^^8
} 4?N8R$
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publicObject load(finalClass entity, !-s!f&_
,1'4o3
finalSerializable id){ pZ`|iLNl-
return getHibernateTemplate().load jF`BjxrG
h%WE=\,Qp
(entity, id); VxP&j0M>
} %0#1t 5g
gOgps:
publicObject get(finalClass entity, `[o)<<}
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finalSerializable id){ Z,BC*
return getHibernateTemplate().get Ehzo05/!
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(entity, id); pEECHk
} (R`B'OtGg
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publicList findAll(finalClass entity){ 9a'-Y
return getHibernateTemplate().find("from '`'GK&)
=b;>?dP
" + entity.getName()); \~P=U;l=pO
} Lb LiB*D#s
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publicList findByNamedQuery(finalString e1//4H::t
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namedQuery){ |t$Ma'P
return getHibernateTemplate !4] 9!<.k
kyR*D1N&)
().findByNamedQuery(namedQuery); jYNrD"n
} CctJFcEZ
kw2T>
publicList findByNamedQuery(finalString query, &A#~)i5gF
BL@:!t
finalObject parameter){ T843":
return getHibernateTemplate F~ Lx|)0M
Em[DHfu1Q
().findByNamedQuery(query, parameter); t6v/sZ{F
} QMv@:Eo
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publicList findByNamedQuery(finalString query, Uye|9/w8 !
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finalObject[] parameters){ z;@*r}H
return getHibernateTemplate 9Fn\FYUq
!8`3GX:B_
().findByNamedQuery(query, parameters); SkU9ON
} V I%
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publicList find(finalString query){ vn/.}GkpU
return getHibernateTemplate().find H@]MXP[_
mf'V)
(query); :[;hu}!&
} [w ;kkMJAy
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publicList find(finalString query, finalObject -G6U$
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parameter){ g^zs,4pPU<
return getHibernateTemplate().find fhB}9i^]tg
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(query, parameter); yDNOt C|
} HSq}7S&U
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public PaginationSupport findPageByCriteria Cu6%h>@K$
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(final DetachedCriteria detachedCriteria){ vv26I
return findPageByCriteria "Ks,kSEzu
:1Sl"?xU
(detachedCriteria, PaginationSupport.PAGESIZE, 0); ON+J>$[[
} jt+iv*2N>
uslQ*7S[^
public PaginationSupport findPageByCriteria +}jJ&Z9)
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(final DetachedCriteria detachedCriteria, finalint 1?Z4K/
;;&}5jcV
startIndex){ hlt[\LP=$
return findPageByCriteria n_'{^6*O
S6fb f>[
(detachedCriteria, PaginationSupport.PAGESIZE, cu+FM
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startIndex); I!^O)4QRx
} fFQ|T:vm
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public PaginationSupport findPageByCriteria 6AocmR0D'
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(final DetachedCriteria detachedCriteria, finalint =*Bl|;>6
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pageSize, w6j/ Dq!
finalint startIndex){ %D * OO{
return(PaginationSupport) Dd`Mv$*d8
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getHibernateTemplate().execute(new HibernateCallback(){ /Z7iLq~t"G
publicObject doInHibernate ;J7F J3n
o=`C<}
(Session session)throws HibernateException { jlxpt)0i
Criteria criteria = Y".RPiTL
* RtgC/
detachedCriteria.getExecutableCriteria(session); *?MGMhE
int totalCount = fDLG>rXPT
=FD;~
((Integer) criteria.setProjection(Projections.rowCount B5$kHM%p
itMg|%B%
()).uniqueResult()).intValue(); D_Bb?o5
criteria.setProjection g:EVhuK
1@$Ko5
(null); tsk)zP,<
List items = n'emNRa
0V?F'<qy
criteria.setFirstResult(startIndex).setMaxResults 8g7<KKw
K<>sOWZ'S
(pageSize).list(); Vx-7\NB
PaginationSupport ps = NF?
vg/{
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new PaginationSupport(items, totalCount, pageSize, &iV{:)L
dUsxvho
startIndex); --DoB=5%8
return ps; ,cqF3
} Q$fmD
}, true); A@Dw<.&_I
} sq'Pyz[[
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public List findAllByCriteria(final VH:]@x//{
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DetachedCriteria detachedCriteria){ #^]n0!
return(List) getHibernateTemplate mml
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x,'!eCKN
().execute(new HibernateCallback(){ z<5m
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publicObject doInHibernate =Qn ;_+Ct
$.bBFWk
(Session session)throws HibernateException { 9H%X2#:fH
Criteria criteria = h;0S%ZC
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detachedCriteria.getExecutableCriteria(session); #BSTlz
return criteria.list(); D|.ic!w'
} twx[s$O'b
}, true); E6 WA}_
} wm^J;<T[
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public int getCountByCriteria(final 2;?I>~
)YqXRm
DetachedCriteria detachedCriteria){ T'~!9Q
Integer count = (Integer) )l#E}Uz
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getHibernateTemplate().execute(new HibernateCallback(){ !* OJ.W&
publicObject doInHibernate .(WQYOMl0
iya"ky~H
(Session session)throws HibernateException { *<!oHEwkN
Criteria criteria = !Xph_SQ!B=
dc rSz4E|>
detachedCriteria.getExecutableCriteria(session); )Qvk*9OS
return -!
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criteria.setProjection(Projections.rowCount [0D
Et
_(KbiEB{
()).uniqueResult(); !e?.6% %
} R,Vd.-5M
}, true); c?@T1h4
return count.intValue(); OiP!vn}k
} n-@j5w+k4
} +U3m#Y )k
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用户在web层构造查询条件detachedCriteria,和可选的 (V HL{rj
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )=etG
6w@ Ii;
PaginationSupport的实例ps。 Y(d$
n9xAPB }
ps.getItems()得到已分页好的结果集 tmtT(
ps.getIndexes()得到分页索引的数组 ::/j$bL
ps.getTotalCount()得到总结果数 9U%N@Dq`Z
ps.getStartIndex()当前分页索引 0MdDXG-7
ps.getNextIndex()下一页索引 .?hP7;hhI
ps.getPreviousIndex()上一页索引 1&U>,;]*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 LoGVwRmoC
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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 W}]%X4<#rN
aT$9;
一下代码重构了。 Xqm::1(-(
.>IhN 5
我把原本我的做法也提供出来供大家讨论吧: MHC^8VL
wg]j+r@
首先,为了实现分页查询,我封装了一个Page类: yYH 0v7vx+
java代码: |x-S&-
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/*Created on 2005-4-14*/ fwRZ5`v<
package org.flyware.util.page; }7.PH'.8
;y2/-tL?
/** d:U9pC$
* @author Joa [`):s= FC
* #gcF"L||
*/ =Yt
R`
publicclass Page { #*(td<Cp
5EebPXBzB
/** imply if the page has previous page */ v3jg~"!
privateboolean hasPrePage; $"H{4x`-
bG(3^"dS
/** imply if the page has next page */ AlIpsJ[UU
privateboolean hasNextPage; ut I"\1hQ
Aj4T"^fv
/** the number of every page */ UTH_^HAN#G
privateint everyPage; Sh8"F@P8
"
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/** the total page number */ ;hjwD
privateint totalPage; CtS l
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/** the number of current page */ LmnymcH
privateint currentPage; i0$kit
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/** the begin index of the records by the current #: [<iSk
*9{Z$IA9w
query */ 7F{3*`/6
privateint beginIndex; '5|h)Q5
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/** The default constructor */ ]f({`&K5
public Page(){ ]&pds\
M!XsJ<jN/
} ikSt"}/hd
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/** construct the page by everyPage nPy$D-L,
* @param everyPage G8Y<1%`<
* */ % V8U(z
public Page(int everyPage){ #Ibp(
this.everyPage = everyPage; 2P@sn!*{1
} Cy=Hy@C
rMhB9zB1
/** The whole constructor */ pxh"B\"4*
public Page(boolean hasPrePage, boolean hasNextPage, bq:(u4 3
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cbT7CG
int everyPage, int totalPage, #a8B/-
int currentPage, int beginIndex){
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this.hasPrePage = hasPrePage; @-!}BUs?
this.hasNextPage = hasNextPage; suzZdkMA
this.everyPage = everyPage; 65aK2MS@
this.totalPage = totalPage; !74S
this.currentPage = currentPage; W|g4z7Pb
this.beginIndex = beginIndex; 7M<'/s
} F6{bjv2A
/Id%_,}Kb
/** [.uG5%fa
* @return K8UP,f2
* Returns the beginIndex. %*0^0wz
*/ 8Y7Q+p|O
publicint getBeginIndex(){ 0p}D(m2B
return beginIndex; 2
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} YLzx<~E4a
=t H:,SH
/** 5?F__Hx*2
* @param beginIndex Z*= $8e@
* The beginIndex to set. x?2@9u8Yb
*/ R&BTA
publicvoid setBeginIndex(int beginIndex){ ~3WF,mW
this.beginIndex = beginIndex; V^Q#:@0
} yU-e3O7L
sWc*5Rt
/** [VsKa\9u
* @return HTS%^<u
* Returns the currentPage. E4~<V=2l
*/ l^pA2yh|
publicint getCurrentPage(){ L"4mL,
return currentPage; ^5h]Y;tx
} ;E3>ay6m8
<?riU\-]y
/** ='s(|
* @param currentPage C8V/UbA
/
* The currentPage to set. 6MT1$7|P&x
*/ Z:sg}
publicvoid setCurrentPage(int currentPage){ <YhB8W9 P
this.currentPage = currentPage; ZL&g_jC
} W;!}#o|%s
%R}.#,Suo
/** JSCZ{vJ$
* @return P;qN(2L/=<
* Returns the everyPage. q#,f 4P
*/ 7G}2,ueI
publicint getEveryPage(){ Y6zbo
return everyPage; 'kL#]
} <~n"m
@oV9)
/** <FcG
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* @param everyPage e}
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* The everyPage to set. "J[K 3
*/ a!"$~y$*
publicvoid setEveryPage(int everyPage){ 3W3ZjdV+
this.everyPage = everyPage; ?"i}^B`*
} g" .are'7
o4K ~
/** e
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* @return WSp
* Returns the hasNextPage. O$&mFL[`
*/ ,}ECF>
publicboolean getHasNextPage(){ &3J_^210
return hasNextPage; uao0_swW5
} S~;4*7+?:
1^7hf;|#g
/** w&o&jAb-M
* @param hasNextPage $Bs {u=+w
* The hasNextPage to set. )ttUWy$w
*/ ,+meT`'vn
publicvoid setHasNextPage(boolean hasNextPage){ 7Z\--=;|[:
this.hasNextPage = hasNextPage; -- %N8L;e
} kt["m.
jY%na
HaI
/** K1\a#w
* @return @Z\,q's
* Returns the hasPrePage. ][9%Kl*%@p
*/ DRp~jW(\y
publicboolean getHasPrePage(){ 1DE<rKI
return hasPrePage; 2.l Z:VLN
} ^Eb.:}!D6
$o0iLFIX/
/** J;{N72
* @param hasPrePage ]|zp0d=&o
* The hasPrePage to set. :y%/u%L
*/ *n 6s.$p)%
publicvoid setHasPrePage(boolean hasPrePage){ &eCa0s?mI
this.hasPrePage = hasPrePage; )4<__|52"1
} W&&;:Fr
vd
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/** <`B,R*H{
* @return Returns the totalPage. :D%"EJ
* Lvq>v0|
*/ GT }F9F~
publicint getTotalPage(){ jV>raCK_
return totalPage; B8V>NvE~o
} 4E]l{"k<
aWWU4xe
/** mKL<<L[
* @param totalPage Li/O
* The totalPage to set. rV R1wsaL
*/
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publicvoid setTotalPage(int totalPage){ 5Iy;oZ
this.totalPage = totalPage; K]s[5
} C":32_q
Gb#Cm]
} >L;eO'D
}z _
"$ Y_UJT7
jkiFLtB@V
bx{$Y_L+p
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 w)kNkD
@eD):Y
个PageUtil,负责对Page对象进行构造: tD(7^GuR
java代码: +cgSC5nR
RrX[|GLSJ
2ORNi,_I
/*Created on 2005-4-14*/ \ 3wfwu.q
package org.flyware.util.page; j9?}j#@
EQb7-vhg
import org.apache.commons.logging.Log; 3DiLk=\~
import org.apache.commons.logging.LogFactory; \W1,F6&j
u frW\X
/** i'H/ZwU
* @author Joa B_nVP
* JJ}0gZ
*/ 8/i!' 0r\
publicclass PageUtil { M=FxB;v
m?pstuUK(
privatestaticfinal Log logger = LogFactory.getLog "HElB9
lef2 X1w}!
(PageUtil.class); (l-tvk4Ln
M)'HCnvs'
/** )6,de2Pb
* Use the origin page to create a new page iop2L51eJ
* @param page C([phT;
* @param totalRecords 3L833zL
* @return e+$p9k~
*/ z=rT%lz6
publicstatic Page createPage(Page page, int # {w9s0:
ZHU5SXu
totalRecords){ <tF9V Jq
return createPage(page.getEveryPage(), J
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96 q_K84K
page.getCurrentPage(), totalRecords); 0E,8R{e
} 0fF(Z0R,
R:e<W/P"
/** r=5{o1"
* the basic page utils not including exception PD&\LbuG
u<3HQ.:;
handler OMWbZ>jB
* @param everyPage WG N=Y~E
* @param currentPage d
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* @param totalRecords Cdas P9"1
* @return page P<l&0dPO8
*/ t]y
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publicstatic Page createPage(int everyPage, int {5%5}[/x
L\)ZC
currentPage, int totalRecords){ -yE/f2PgQ
everyPage = getEveryPage(everyPage); QrB@cK]
currentPage = getCurrentPage(currentPage); KM}f:_J*lg
int beginIndex = getBeginIndex(everyPage, r"``QmM
%X4xv_o`f
currentPage); WF1px %
int totalPage = getTotalPage(everyPage, 9K5pwC\$%
),U X4%K=
totalRecords); Gb8D[1=u=
boolean hasNextPage = hasNextPage(currentPage, ,4zmb`dP<
U]^HjfX\
totalPage); 8TGOx%}i
boolean hasPrePage = hasPrePage(currentPage); O4r0R1VQM
NLUT#!Gr
returnnew Page(hasPrePage, hasNextPage, P|.] DJ
everyPage, totalPage, 5b!vgm#])
currentPage, ;i
Fz?d3;
!lf|7
beginIndex); ap&?r`Tu
} i=i(%yQ%
v@Gl|29_
privatestaticint getEveryPage(int everyPage){ W%T>SpFl
return everyPage == 0 ? 10 : everyPage; 73V|6tmgY
} q}~3C1
?&|5=>u2}$
privatestaticint getCurrentPage(int currentPage){ \R|4( +]x
return currentPage == 0 ? 1 : currentPage; HG+%HUO$
} ]bj&bk#
.q
`Hjmg<
privatestaticint getBeginIndex(int everyPage, int gCioq.
lzYEx
currentPage){ o_@4Sl8
return(currentPage - 1) * everyPage; n#q<`}u,
} K8>zF/# +
BybW)+~
privatestaticint getTotalPage(int everyPage, int 85n1eE
D}dn.$
totalRecords){ f0X_fm_q
int totalPage = 0; bn^{c
PV9pa/`@
if(totalRecords % everyPage == 0) `S6x<J&T\/
totalPage = totalRecords / everyPage; BFL`!^
else uT}' Y)m
totalPage = totalRecords / everyPage + 1 ; 5]n[]FW
V}dJ.I /#
return totalPage; J4Nln
} AtdlZ
2] zq#6ix
privatestaticboolean hasPrePage(int currentPage){ A D1=[I3
return currentPage == 1 ? false : true; (iL|Sq&}b
} f!s=(H;
ny`#%Vs
privatestaticboolean hasNextPage(int currentPage, N F+iza;DP
2^^`n1?'
int totalPage){ 9?0^ap,T
return currentPage == totalPage || totalPage == vg3=8>#
_9=Yvc=
0 ? false : true; =bHD#o|R
} `glBV`?^
^:#D0[
A9wh(P0\
} !q9+9 *6
2
dAB-d:k
~kZ G{
zx-81fx+k
\De{9v
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。 c- }X_)U }
vU767/
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 95YL]3V
%]>KvoA
做法如下: +n#V[~~8AI
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :a$\/E =
~nrK>%
的信息,和一个结果集List: 0URji~?|x
java代码: c&AygqN
4WJ.^ (
cFeXpj?GV
/*Created on 2005-6-13*/
yls
^ cyX
package com.adt.bo; v#.r.{t
ig/%zA*Bo
import java.util.List; .Yf:[`Q6g
VxVE
import org.flyware.util.page.Page; dYL"h.x
(+B5|_xQu
/** =>M^02"
* @author Joa r7b1-
*/ 5*1D$mxD"
publicclass Result { fZ*+2T>
vJ'2@f$
private Page page; s;3= {e.
M7@2^G]p
private List content; ;\=M;Zt
[N/"5
[
/** h&--,A >
* The default constructor /(iFcMT
*/ =zKhz8B(
public Result(){ ApAO/q
super(); :E:38q,hG
} (H
->IV
PK0%g$0
/** *XT/KxLa7
* The constructor using fields FQqI<6;
* D^=J|7e
* @param page Pmh8sw
* @param content wS%Q<uK
*/ e A#;AQm
public Result(Page page, List content){ T3k#VNH
this.page = page; -(f)6a+H
this.content = content; MP!d4
} PX<J&rx
vTJ}8
/** %k'!Iq+
* @return Returns the content. c.>oe*+
*/ :TJv=T'p'
publicList getContent(){ jO!y_Y]B
return content; O"F_*
} k3)dEH1z
mg*qiScfW
/** Hm%;=`:'
* @return Returns the page. rvnT6Ve
*/ A^)?Wt%*
public Page getPage(){ 0V'nK V"|
return page; Mf&{7%
} (]Y 5eM
m<j8cJ(
/** m^GJuPLW
* @param content Si6al78
* The content to set. LIZRoG8
*/ ha(Z<
public void setContent(List content){ .y@oz7T5
this.content = content; ]
:BX!<
} sB c
(gr
Q\
U:~g3
/** iZaI_\"__
* @param page !f&Kf,#b`
* The page to set. :=wTvz
*/ }j*KcB_
publicvoid setPage(Page page){ N6 (
this.page = page; qoj$]
} B[Zjfc
} XT@-$%u
li0i"
]>~)<
M;p
em<
IHJ=i-
2. 编写业务逻辑接口,并实现它(UserManager, Q4f/Z
Hhari!RXC
UserManagerImpl) 2@%$;.
java代码: <iH`rP#
^OstR`U3
K)Q]a30
/*Created on 2005-7-15*/ <xgTS[k
package com.adt.service; PzA|t;*
L"{JRbh[
import net.sf.hibernate.HibernateException; ;)!Sp:mHX
]8f ms(
import org.flyware.util.page.Page; +(C6#R<LI
B,TB3
{
import com.adt.bo.Result; WXmn1^"kK}
vfq%H(
/** HA2k[F@3^
* @author Joa ,]+z)
*/ \hM|(*DL
publicinterface UserManager { Bc6|n :;u
}RwSp!}C
public Result listUser(Page page)throws q.2ykL
3>R#zJf
HibernateException; %=/)
~Uxsn@nLr
} uoXAQ6k
L7VG`h;
\>7^f
3m
O }(VlR2
^V#@QPK9
java代码: lsy?Ac
GQ9\'z#+
7D!u1?]d{
/*Created on 2005-7-15*/ KN7n@$8YM
package com.adt.service.impl; %oq[,h
<X
1. rj'
import java.util.List; L(khAmm
l PK
+$f$
import net.sf.hibernate.HibernateException; ,=|ZB4HA
+ j W1V}h
import org.flyware.util.page.Page; w0C~*fn3l
import org.flyware.util.page.PageUtil; unBy&?&p
*7h!w!LN~
import com.adt.bo.Result; Up,vD)tG
import com.adt.dao.UserDAO; D,g1<:<
import com.adt.exception.ObjectNotFoundException; hNd}Y'%V
import com.adt.service.UserManager; lhw()u
wAxrc+
/** T`Mf]s)*
* @author Joa k&.Jk
B"
*/ US%^#D q
publicclass UserManagerImpl implements UserManager { DXa-rk8
Hrz f'a|^
private UserDAO userDAO; >&p0d0
t$A%*JBKm
/** %"af748!+D
* @param userDAO The userDAO to set. IjR'Qou5
*/ RW }"2
publicvoid setUserDAO(UserDAO userDAO){ yRiP{$E
this.userDAO = userDAO; -tyK~aasQ
} 4=Krq6{
H8`(O"V
/* (non-Javadoc) iTV) NsC}
* @see com.adt.service.UserManager#listUser $pFo Rv
Q~j`YmR|
(org.flyware.util.page.Page) XLH+C ]pfr
*/ vsr[ur[eP
public Result listUser(Page page)throws cg*)0U-_(
a(v>Q*zNP
HibernateException, ObjectNotFoundException { .?!N^_ Ez3
int totalRecords = userDAO.getUserCount(); V`7FKL@"
if(totalRecords == 0) ^pe{b9c
throw new ObjectNotFoundException +{L<? "
YBP:q2H
("userNotExist"); K!] 1oy'V
page = PageUtil.createPage(page, totalRecords); M>>qn_yq4
List users = userDAO.getUserByPage(page); ,i,q!M{-
returnnew Result(page, users); ,$
^C4I
} aN $}?
YI.w-K\
} i7utKj*57
bLd#xXl
X0M1(BJgGo
SJ};TEA
qg}O/K
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 "eWYv3z~-
&_gTD
询,接下来编写UserDAO的代码: @;H,gEH^
3. UserDAO 和 UserDAOImpl: p$x{yz3
java代码: " $ew~;z
Iz{R}#8CZ
sPb=82~z
/*Created on 2005-7-15*/ =T7A]U]
package com.adt.dao; yT#{UA^
9gEssTkts
import java.util.List; Myq5b`z
o, !T2&}
import org.flyware.util.page.Page; eU N"w,@y
C$@yG)Pj
import net.sf.hibernate.HibernateException; p!<$vE
{M?vBgR\B
/** yGsz2T;w
* @author Joa B-T/V-c7
*/ _"#!e{N|
publicinterface UserDAO extends BaseDAO { n]u<!.X
yH<$k^0r*
publicList getUserByName(String name)throws E gDQ+(
-
H=\!2XS
HibernateException; )5.C]4jol
L:k9#6
publicint getUserCount()throws HibernateException; %O<%UmR
8B#GbS
K
publicList getUserByPage(Page page)throws M!tXN&V]
A?oXqb
HibernateException; !Y:0c#MPH
-Z?Vd!H:
} bQZ*r{g
QZ?=M@|f
W(Uu@^
4#'("#R
*k1<:
@%e
java代码: X K5<Tg
6Kj'ZyVL
rX; Ys2vQ*
/*Created on 2005-7-15*/ \^V`ds*.
package com.adt.dao.impl; !2|=PB' M
[M%9_CfZOy
import java.util.List; p*8-W(u)
\6 93kQ
import org.flyware.util.page.Page; ee/&/Gt
W},b{NT
import net.sf.hibernate.HibernateException; ejO}t:}P
import net.sf.hibernate.Query; zP;cTF(C
R i'L
import com.adt.dao.UserDAO; $DP&a1'g
Na\WZSu'"
/** atW'
* @author Joa Go&D[#
*/ @y/wEBb
public class UserDAOImpl extends BaseDAOHibernateImpl _HA$
j2
Jy
aag-
implements UserDAO { x+@&(NMP5
`+/H^
/* (non-Javadoc) wO>L#"X^v
* @see com.adt.dao.UserDAO#getUserByName :SsUdIX;P
7E @+
(java.lang.String) 4A3nO<oMF
*/ }I!hOD>]O
publicList getUserByName(String name)throws P N*JR
olW|$?
HibernateException { 6ITLGA
String querySentence = "FROM user in class *E~VKx1
5eA8niq#
com.adt.po.User WHERE user.name=:name"; u<n`x6gL
Query query = getSession().createQuery JNFIT;L
BvU"4d;x
(querySentence); j2Pn<0U
query.setParameter("name", name); 1'4J[S\cM
return query.list(); =5sF"L;b
} %G@5!|J
6st^4S5
/* (non-Javadoc) $^tv45
* @see com.adt.dao.UserDAO#getUserCount() |Cdvfk
*/ Kwhdu<6
publicint getUserCount()throws HibernateException { {R^'=(YFy
int count = 0; sgr=w+",Q
String querySentence = "SELECT count(*) FROM %ObD2)s6:^
3[XQR8o
user in class com.adt.po.User"; h)v^q: ='
Query query = getSession().createQuery Oc&),ru2l
v[lnw} =m9
(querySentence); &-1./?
count = ((Integer)query.iterate().next @wq#>bm
?'r9"M>
()).intValue(); ?Mp1~{8
return count; s(_+!d6
} z\/53Sy<
6TH!vuQ1(
/* (non-Javadoc) ~^vC,]hU
* @see com.adt.dao.UserDAO#getUserByPage C#w]4 $/
jvVi%k
(org.flyware.util.page.Page) b8f+,2Tk
*/ htPqT,L
publicList getUserByPage(Page page)throws ^I]{7$6^
L"<B;u5pM
HibernateException { f'6|OsVQ
String querySentence = "FROM user in class somfv$'B
)uLr?$qe
com.adt.po.User"; 9B+wYJp
Query query = getSession().createQuery +/?iCmW
+^6}
(querySentence); n$2 RCQ
query.setFirstResult(page.getBeginIndex()) \nqo%5XL
.setMaxResults(page.getEveryPage()); &gc`<kLu
return query.list(); hFvi5I-b
} @rb l^
\Z/k;=Sla
} ZB5?!.ND
MF[z-7
jK8'T_Pah
P.sgRsL
k:#6^!b1
至此,一个完整的分页程序完成。前台的只需要调用 l
oqvi
Gowp
<9 F
userManager.listUser(page)即可得到一个Page对象和结果集对象 a-n4:QT
iS@\ =CK
的综合体,而传入的参数page对象则可以由前台传入,如果用 |)W!jC&k
Ak~4|w-
webwork,甚至可以直接在配置文件中指定。 FyG6!t%
0>!/rR7
下面给出一个webwork调用示例: WP-jtZ?!"
java代码: A6ewdT?>,
Qrz4}0
#X.+
/*Created on 2005-6-17*/ ~DLIz g7p!
package com.adt.action.user; 'Zk<l#"}
eSl-9
^
import java.util.List; 3z{S}~
4x'AC%&Qi
import org.apache.commons.logging.Log; M+sj}
import org.apache.commons.logging.LogFactory; bO49GEUT _
import org.flyware.util.page.Page; ~_ !ts{[E
Xz;b,C&*t
import com.adt.bo.Result; .F0]6#(
import com.adt.service.UserService; #B\=Aa`*
import com.opensymphony.xwork.Action; JatHSW7j9
fo\\o4Qyh
/** r3I,11B
* @author Joa 4Y
tk!oS`
*/ ~hURs;Sb
publicclass ListUser implementsAction{ ${U6=
oVZ4bRl
privatestaticfinal Log logger = LogFactory.getLog nR8]@c C
LD+f'^>>Z
(ListUser.class); gZ(O)uzv
'=} Y2?(
private UserService userService; pH9HK
h'^FrWaU/
private Page page; N"DY?6
a]1i/3/
privateList users; F>:%Cyo0!
ID8k/t!
/* B[NJ^b|
* (non-Javadoc) 1&|Dsrj
* 2
X<nn
* @see com.opensymphony.xwork.Action#execute() \Tq"mw9P
*/ Xyv8LB
publicString execute()throwsException{ K="I<bK
Result result = userService.listUser(page); '7nJb6V,0l
page = result.getPage(); i+~QDo(Pi
users = result.getContent(); vmKTF!;
return SUCCESS; T2bnzIi
} ) Ypz!
ItK
/** X*Z5 P
* @return Returns the page. o_yRn16
*/ xQz#i-v
public Page getPage(){ ^now}u9S6
return page; NyJnOw(
} 4/L>&%8V
?~qC,N [
/** L_*L`!vQA"
* @return Returns the users. \o9@[t>&2
*/ 6H;kJHn
publicList getUsers(){ $T*KaX\{B
return users; E:Y:X~vy
} II#
/8p&Qf>lJ1
/**
f-vK}'Z`,
* @param page 1PU*:58[
* The page to set. C
MqM;1
*/ }Z6nN)[|0Y
publicvoid setPage(Page page){ , ;'SVe%
this.page = page; ct\<;I(H
} 0=m&^Jpp
fI[dhd6
/** A*Q[k 9B
* @param users
-HT L5
* The users to set. 4GTrI@}3
*/ u'@Ely
publicvoid setUsers(List users){ 9}whWh
this.users = users; &5/JfNe3
} wU0K3qZL
Ak|b0l>^
/** UQdyv(jXq
* @param userService Bi_J5 If
* The userService to set. 9&(.x8d,a
*/ 3^H/LWx`{]
publicvoid setUserService(UserService userService){ ,%= '>A
this.userService = userService; c+;S<g0
} jmPp-}tS7
} S%V%!803!
nB}e1
/_y
/a%KS3>V*
9<qx!-s2rr
ZX]A )5G
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, -$tCF >,
tnRJ#[Io
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ' WnpwY
O<iI
么只需要: 3AP YO
java代码: 6+#,=!hF{
(6[Wr}SW5
(\q[gyR
<?xml version="1.0"?> jQIV2TY[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [5pn@o
4`G=q^GL,
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /^QFqM;
iXnx1w
1.0.dtd"> i\Q":4
PE7t_iSV
<xwork> >!G5]?taa
E$&;]a
<package name="user" extends="webwork- .)nCOwR6p
;l#?SYY
interceptors"> U*xxrt/On/
,"C&v~
<!-- The default interceptor stack name ^B6`e^<
6fQ*X~| p
--> Q^kMCrp
<default-interceptor-ref k#-[ M.i
p|;o5j{
name="myDefaultWebStack"/> SOYDp;j
Vg) ^|
<action name="listUser" 6<Be#Y]b
h?3f5G*&H
class="com.adt.action.user.ListUser"> t.u{.P\Md\
<param x6~Fb~aP
# m_\1&g
name="page.everyPage">10</param> t3M0La&
<result 2PI #ie4
b__n~\q_
name="success">/user/user_list.jsp</result> PKATw>zg<
</action> ~EPjZ3 ?
s!=!A
</package> }K+\8em
~JT lPU'
</xwork> H|'$dO)W
q2D`1nT
;?#i]Bh>S
aeQ{_SK
{bxhH)a'
UFJEs[?+Te
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 _4g}kL02.
hkLw&;WJr
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6l=M;B7:i
W|FNDP0
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ud!r*E
&8.z$}m
kv[OW"8t
Psg +\ 14
N/`g?B[
我写的一个用于分页的类,用了泛型了,hoho o(BYT9|.kw
WJP`0f3
java代码: `~sf}S
:
KF*B
]IL3 $eR
package com.intokr.util; "P9wT)J_
<`^>bv9
import java.util.List; )vxVg*.Ee
30e(4@!4vW
/** vBV"i9n
* 用于分页的类<br> mq>*W'M
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 6k@[O@)
* YL_!#<k@
* @version 0.01 5Xla_@WLW
* @author cheng oM m/!Dc
*/ ]ZBgE\[
public class Paginator<E> { Ebmqq#SHjX
privateint count = 0; // 总记录数 InTKdr^ P
privateint p = 1; // 页编号 6S` ,j
privateint num = 20; // 每页的记录数 HP1X\h!Ke
privateList<E> results = null; // 结果 h%4~0
=r=^bNO
/** hnlU,p&y3
* 结果总数 "Vs
Nyy
*/ |J@|
publicint getCount(){ )3d:S*ly
return count; _AA`R`p;
} bi,rMgW
c'>8pd
publicvoid setCount(int count){ 0^_)OsFA
this.count = count; a .B\=3xn
} PLlx~A
#nt<j2}m
/** <L[ *hp
* 本结果所在的页码,从1开始 ZzwZ,(
* m|g$'vjk
* @return Returns the pageNo. %DHP
*/ $Ykp8u,(
publicint getP(){ 4p0IBfVG
return p; D<$j`r
} LKoM\g(
K'ed5J
/** u^;sx/
* if(p<=0) p=1 %6vMpB`g
* EC:x,i
* @param p _~(MA-l
*/ y^vfgP<@
publicvoid setP(int p){ S<)RVm,!e
if(p <= 0) 6-Vl#Lyb
p = 1; Ra*k
this.p = p; INeWi= 1
} %u<&^8EL+#
AX^3uRQJ
/** xf{C'uF/
* 每页记录数量
$Adp
*/ M?:f^
publicint getNum(){ vs)HbQ
return num; (>kBmK1Aj
} '3Y0D1`v
\^^hG5f
/** 4%Z\G@0<'
* if(num<1) num=1 P,+0
*/ 2t~7eI%d
publicvoid setNum(int num){ O=9V X
if(num < 1) p>w~T#17
num = 1; WL*W=(
this.num = num; $e^ :d
} }r\SP3
,T1XX2?:
/** ~P_d0A~T
* 获得总页数 /(z0I.yE
*/ [0%Gu5_\
publicint getPageNum(){ p'9
V._h
return(count - 1) / num + 1; @O*ev|o@x
} 8P'En+uE1|
FK/ro91L
/** vX!dMJa0
* 获得本页的开始编号,为 (p-1)*num+1 1Tts3O.
*/ U_=wL
publicint getStart(){ CgPZvB[
return(p - 1) * num + 1; S{r)/~/
} 9-e[S3ziM
[b\lcQ8O
/** hr
6LB&d_
* @return Returns the results. bx%hizb
*/ `U?H^,FVA
publicList<E> getResults(){ LQ&d|giA
return results; 5)o-]S>
} 9lazo
V.G9J!?<P
public void setResults(List<E> results){ MX< ($M
this.results = results; *j|Tm7C
} 8-l)TTP&.
`Mh<S+/
public String toString(){ Wcay'#K,
StringBuilder buff = new StringBuilder $dWl A<u
0e5-\a
(); >t6'8g"T
buff.append("{"); 7;#dX~>@{
buff.append("count:").append(count); OYRR'X.E
buff.append(",p:").append(p); lCs8`bYU
buff.append(",nump:").append(num); ."#jN><t
buff.append(",results:").append h0EGhJs
m6ZbYF-7W
(results); ZJJl944
buff.append("}"); ,uD*FSp>
return buff.toString(); G5e Ls
} v!v0,?b*
B}xo|:f!zj
} {Z{NH:^
qh'f,#dI}
7{/:,