Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 h!]A(T\J
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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 '& :"/4@)
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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 u&bU !ZI
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分页支持类: >S]')O$c
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java代码: Zv93cv
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package com.javaeye.common.util; @9a=D<'>
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import java.util.List; A@r,A?(
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publicclass PaginationSupport { ]={Hq9d@
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publicfinalstaticint PAGESIZE = 30; z(qz(`eGC&
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privateint pageSize = PAGESIZE; iI7~9SCE
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privateList items; 470Pig>I8
P $S P4F
privateint totalCount; IF1}}[Ht
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privateint[] indexes = newint[0]; "
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privateint startIndex = 0; jEI L(0_H
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public PaginationSupport(List items, int WTx;,TNG
@dNbL}qQ
totalCount){ ;*p}~#2
setPageSize(PAGESIZE); J)o%83//
setTotalCount(totalCount); ,?+yu6eLb
setItems(items); >rubMGb
setStartIndex(0); +l(}5(wc
} ><~hOK?v
I5]zOKlVR
public PaginationSupport(List items, int yk/XfwQ5
\\JXY*DA:+
totalCount, int startIndex){ +L6d$+
setPageSize(PAGESIZE); "?SnA +)
setTotalCount(totalCount); v},sWjv
setItems(items); WW=7QCi
setStartIndex(startIndex); @$]h[
} S8l+WF4q
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public PaginationSupport(List items, int /Y:Zqk3
HFOp4
totalCount, int pageSize, int startIndex){ p(Mv^ea
setPageSize(pageSize); l<+k[@Vox
setTotalCount(totalCount); ~4 ab\hq
setItems(items); c/RG1w
setStartIndex(startIndex); Y|F);XXIl
} rH,N.H#]
, utFCZW
publicList getItems(){ OgX."pK
return items; G)Y!aX
} _[W=1bGJ
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publicvoid setItems(List items){ )<d8y Lb
this.items = items; S5JnJkNn
} K9R[
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bu-
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publicint getPageSize(){ .@'Vz;&mQ
return pageSize; m\yO/9{h1
} rGs> {-T3
_PF><ODX2
publicvoid setPageSize(int pageSize){ V]2Q92
this.pageSize = pageSize; .;'xm_Gw<
} F+GQ l
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qbj;
publicint getTotalCount(){ b~}}{fm&f
return totalCount; M%/D:0
} Ts\7)6|F
!wgj$5Rw.
publicvoid setTotalCount(int totalCount){ )'JSu=Ej
if(totalCount > 0){ 6x 0>E^~
this.totalCount = totalCount; B}W^s;h
int count = totalCount / 1K>4i. X
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pageSize; 8'y|cF%U
if(totalCount % pageSize > 0) 8Bhng;jX
count++; u8*0r{kOH
indexes = newint[count]; r"+
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for(int i = 0; i < count; i++){ kcle|B
indexes = pageSize * ;1KhUf;&F
t%)L8%Jr
i; vzL>ZBeZ
} kQ +
}else{ <FP-]R)
this.totalCount = 0; Xp'KQ1w)
} f]Vz !hM~
} N|DY)W
x{rt\OT
publicint[] getIndexes(){ sb1/4u/W
return indexes; HwHI$IB
} vI-KH:r"{
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publicvoid setIndexes(int[] indexes){ U+KbvkX wj
this.indexes = indexes; $jHL8r\e7
} SNQ+ XtoO
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publicint getStartIndex(){ &+\wYa,
return startIndex; I
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} o}T]f(>}
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publicvoid setStartIndex(int startIndex){ .D :v0Zm}m
if(totalCount <= 0) tQ/U'Ap&
this.startIndex = 0; er53?z7zP.
elseif(startIndex >= totalCount) .}tL:^'~o
this.startIndex = indexes HV}NT~
Y !`H_Qo
[indexes.length - 1]; ;j$84o{
elseif(startIndex < 0) *q^'%'
this.startIndex = 0; !MbRI
else{ G
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this.startIndex = indexes _?{2{^v
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[startIndex / pageSize]; F?UL0Q|u v
} BjA|H
} !%Ak15o
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publicint getNextIndex(){ 7l?=$q>k"
int nextIndex = getStartIndex() + k=LY 6
HwDb &pP"
pageSize; +G?3j ,a\
if(nextIndex >= totalCount) )T>a|.
return getStartIndex(); eN/Jb;W
else @-hy:th#
return nextIndex; h.67]U7m
} 8'zwyd3
c6e?)(V>
publicint getPreviousIndex(){ X3nwA#If1
int previousIndex = getStartIndex() - U<*dDE~z
*@O;IiSE
pageSize; 0Vg8o @
if(previousIndex < 0) $lO\eQGxB
return0; z.QW*rW9
else }%VHBkuc
return previousIndex; 1Ao"DxZHy7
} 9<R:)Df
o:?IT/>
} 7QQnvoP
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抽象业务类 KVK@Snn
java代码: 6ds&n#n
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/** 5bgx;z9
* Created on 2005-7-12 Lg'z%pi
*/ Q 5Ln'La$
package com.javaeye.common.business; d~.#K S
A>X#[qx
import java.io.Serializable; EB)0 iQ
import java.util.List; p}C3<[Nk
RlpW)\{j?
import org.hibernate.Criteria; ?A]:`l_"
import org.hibernate.HibernateException; aa$+(
import org.hibernate.Session; HbCM{A9
import org.hibernate.criterion.DetachedCriteria; Z{%h6""
import org.hibernate.criterion.Projections; |`,%%p|T%
import f9;M"Pd
A6-JV8^
org.springframework.orm.hibernate3.HibernateCallback; _v_ak4m>
import +|^rz#X
,UY],;ib
org.springframework.orm.hibernate3.support.HibernateDaoS ^G5_d"Gr
S]k<Ixvf
upport; ETYw
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import com.javaeye.common.util.PaginationSupport; *`|F?wF
).xQ~A\.
public abstract class AbstractManager extends v\Q${6kEtx
kGCd!$fsk
HibernateDaoSupport { ZU/6#pb
-(~CZ
privateboolean cacheQueries = false; $n!saPpxS
NCBS=L:
privateString queryCacheRegion; `ez_
{
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publicvoid setCacheQueries(boolean U ^[<G6<9]
7?e*b(vd
cacheQueries){ vWwp'q
this.cacheQueries = cacheQueries; e;!si>N
} g;vG6!;E\
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publicvoid setQueryCacheRegion(String =ejkE;
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queryCacheRegion){ ]r{y+g|
this.queryCacheRegion = 6!O~:\`DJ
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queryCacheRegion; !fjDO!,!
} Kh}#At^C8e
9>%ti&_-jt
publicvoid save(finalObject entity){ mZ'`XAS ~;
getHibernateTemplate().save(entity); *RivZ
c9;P
} ;i> |5tEy
*JUP~/Nr
publicvoid persist(finalObject entity){ Ac|IBXGa=
getHibernateTemplate().save(entity); ?(4=:o
} yY[N\*P
cd#@"&r
publicvoid update(finalObject entity){ o{lR_
getHibernateTemplate().update(entity); g7rn|<6FI
} hr(E,TAe
ma,H<0R
publicvoid delete(finalObject entity){ ;5?$q
getHibernateTemplate().delete(entity); +.:- :
} ):31!IC
#zyEN+
publicObject load(finalClass entity, )u`q41!
L
slI!.(
finalSerializable id){ :[?hU}9
return getHibernateTemplate().load Q!iM7C!8
iG^o@*}a
(entity, id); O'*KNJX
} e3}`]
qlNK }
publicObject get(finalClass entity, 2r]80sWY
l`M{Ravvn*
finalSerializable id){ fczId"
return getHibernateTemplate().get |gg6|,Bt4
tI ~.3+F
(entity, id); =`Pgo5A
} sEm-Td+A5
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publicList findAll(finalClass entity){ 1/:WA:]1,
return getHibernateTemplate().find("from ozy~`$;c
&A)AV<=>T
" + entity.getName()); Y/?V%X
} Bq3" l%hI
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publicList findByNamedQuery(finalString f.-b.nNf
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namedQuery){ >08'+\~:b
return getHibernateTemplate -<h4I
aM
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().findByNamedQuery(namedQuery); )!z<q}i5
} n** W
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publicList findByNamedQuery(finalString query, f~
kz=R=
h fZY5+Z<
finalObject parameter){ la+RK
return getHibernateTemplate F!(Vg
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().findByNamedQuery(query, parameter); H]As2$[
} F,5~a_GP?
3 }~.#`QeY
publicList findByNamedQuery(finalString query, )_BQ@5NK
(?4m0Sn>#h
finalObject[] parameters){ k+b!Lw!L
return getHibernateTemplate jwhc;y
jMr [UZ
().findByNamedQuery(query, parameters); |C"(K-do
} yK9:LXhf
e!k1GTH^
publicList find(finalString query){ RC?gozBFJ
return getHibernateTemplate().find >%LZ|*U
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(query); ynY(
} Vi1l^ Za
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publicList find(finalString query, finalObject tZ\e:AAi
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parameter){ c[VVCN8dA
return getHibernateTemplate().find b$FK}D5
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(query, parameter); eLF xGZ Z
} u|(;SY
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public PaginationSupport findPageByCriteria [~_)]"pU
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(final DetachedCriteria detachedCriteria){ 7]sRHX0o%
return findPageByCriteria JX!z,X?r4
&FrUj>i
(detachedCriteria, PaginationSupport.PAGESIZE, 0); HE!"3S2S&+
} 0MpZdJ
=)b!M^=X-a
public PaginationSupport findPageByCriteria @~7y\G
=1#obB
(final DetachedCriteria detachedCriteria, finalint m4\e`nl
D*=.;Rq
startIndex){ A4{14Y;?
return findPageByCriteria [/=Z2mtA
Yw(O}U 5e
(detachedCriteria, PaginationSupport.PAGESIZE, _p*a`,tK
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startIndex); l6_dVK;s
} iHa:6
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public PaginationSupport findPageByCriteria M:M"7>:
&c[ISc>N{
(final DetachedCriteria detachedCriteria, finalint Uv) B
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pageSize, Z1}@N/>>
finalint startIndex){ iWGn4p'
return(PaginationSupport) o[^nmHrM2
~V t?'v20@
getHibernateTemplate().execute(new HibernateCallback(){ %fuV]
publicObject doInHibernate 3QI. |;X
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(Session session)throws HibernateException { 'nIKkQ" N
Criteria criteria = 3-/F]}0y6
H|)F-aL[
detachedCriteria.getExecutableCriteria(session); pJdR`A-k|
int totalCount = I|x?
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((Integer) criteria.setProjection(Projections.rowCount Y6 <.]H
gWD46+A){
()).uniqueResult()).intValue(); ?ESsma6
criteria.setProjection 3d`u!i?/
v?Zo5uVoq
(null); DuQW?9^232
List items = {h*)|J
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criteria.setFirstResult(startIndex).setMaxResults g@zhhBtQ
Y{d-k1?s5
(pageSize).list(); J
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PaginationSupport ps = tdsfCvF=a
"IHFme@^
new PaginationSupport(items, totalCount, pageSize, H-,p.$3}
y[{}124
startIndex); 3ytlD '
return ps; Na>w~
} !aB~G}'
}, true); O70#lvsM;
} ;I9g;}
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public List findAllByCriteria(final s^> >]
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DetachedCriteria detachedCriteria){ 2kcDJ{(
return(List) getHibernateTemplate S2jn pf}
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().execute(new HibernateCallback(){ dsU'UG7L
publicObject doInHibernate 0`/CoP<U
Q{|_"sfJ
(Session session)throws HibernateException { `mthzc3W
Criteria criteria = wQ^RXbJI9
$[g#P^
detachedCriteria.getExecutableCriteria(session); Te%V+l
return criteria.list(); k4PXH
} _lDNYpv
}, true); |%oI,d=ycv
} B.C:06E5
d#HlO}
public int getCountByCriteria(final x1h&`QUP
pAws{3(Q
DetachedCriteria detachedCriteria){ 2w}l!'ue
Integer count = (Integer) 2>[xe
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getHibernateTemplate().execute(new HibernateCallback(){ 8<x&
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publicObject doInHibernate j&u/T
sXmP<c
(Session session)throws HibernateException { O"X:3srJ`
Criteria criteria = M._;3_)%/
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detachedCriteria.getExecutableCriteria(session); '#C5m#v
return ce[
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criteria.setProjection(Projections.rowCount v\@pZw=x
Jj/}GVNc7
()).uniqueResult(); (tyky&$!
} GExr] 2r
}, true); kl1/(
return count.intValue(); 34QW^{dgE
} I7W`\d)
} g[*"LOw
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用户在web层构造查询条件detachedCriteria,和可选的 {+]tx46$
W^7yh&@lU
startIndex,调用业务bean的相应findByCriteria方法,返回一个 jgiS/oW
\a4X},h\
PaginationSupport的实例ps。 $;&l{=e2)
AB{zkEuK
ps.getItems()得到已分页好的结果集 +cbF$,M4
ps.getIndexes()得到分页索引的数组 .C.b5x!
ps.getTotalCount()得到总结果数 _K&Hiz/'
ps.getStartIndex()当前分页索引 XG!6[o;
ps.getNextIndex()下一页索引 ]j!pK4
ps.getPreviousIndex()上一页索引 ;%Px~g
G3 |x%/Fbp
,!, tU7-H
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w+r).PS}C
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} '?qUy3x
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8A5/jqnqt
x4/{XRQ
,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 6{{<+
o
{kBsiSvsA;
一下代码重构了。 ]28j$)6
UCXRF
我把原本我的做法也提供出来供大家讨论吧: !^8X71W|
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首先,为了实现分页查询,我封装了一个Page类: hs5>Gx
java代码: *dxm|F98
%%/8B
1Q!kk5jE
/*Created on 2005-4-14*/ rB{w4
package org.flyware.util.page; &4+|{Zx0
7#W]Qj
/** ZyDNtX%
* @author Joa }n
"5r(*^@
* )t@9!V
*/ 7r50y>
publicclass Page { yj@k0TWT$
6)p8BUft
/** imply if the page has previous page */ S>>wf:\ c
privateboolean hasPrePage; wdAKU+tM
}O>4XFj
/** imply if the page has next page */ 4lWqQVx
privateboolean hasNextPage; VdGVEDwz
ya{`gjIlW
/** the number of every page */ ] jY^*o[
privateint everyPage; -8Hc M\b
z9g ++]rkJ
/** the total page number */ U[|5:qWs
privateint totalPage; 3tCTPZy
&F/-%l!
/** the number of current page */ Q"B8l[
privateint currentPage; 6^t#sEff]
6%h%h: e
/** the begin index of the records by the current O_7}H)
'l=>H#}<B
query */ $8i`h}AM
privateint beginIndex; R<Mc+{*>
%8D>aS U
g1|Pyt{
/** The default constructor */ t0jE\6r
public Page(){ IG# wY
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} }^0'IAXi
%#rtNDi
/** construct the page by everyPage 7K
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* @param everyPage [k>{q+MWK
* */ oe.Jm#?2.
public Page(int everyPage){ ZG2EOy
this.everyPage = everyPage; ?O+.
} &6C]|13;
tq~4W% p/
/** The whole constructor */ l^}u S|c(
public Page(boolean hasPrePage, boolean hasNextPage, )c&ya|h
6)ibXbH
6u #eLs
int everyPage, int totalPage, 1U#W=Fg'
int currentPage, int beginIndex){ _B#x{ii
this.hasPrePage = hasPrePage; -(F}=o'
this.hasNextPage = hasNextPage; B1J,4
this.everyPage = everyPage; yf0v,]v[
this.totalPage = totalPage; pi~5}bF!a
this.currentPage = currentPage; as]M%|/-I
this.beginIndex = beginIndex; Im\ ~x~{
} z,$uIv}'@
S6(48/
/** @--"u_[
* @return g-wE(L
* Returns the beginIndex. .%{B=_7
*/ D4@?>ek6U
publicint getBeginIndex(){ LdH1sHy*d`
return beginIndex; \1gAWUt('
} m3Wc};yE*Q
E
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/** p0 X%^A,4
* @param beginIndex O5vfcX4>
* The beginIndex to set. <uv`)Q 9
*/ %6 Av1cv
publicvoid setBeginIndex(int beginIndex){ ]T'8O`
this.beginIndex = beginIndex; G#e]J;
} \fEG5/s}T
kJJiDDL0;*
/** G-2~$ u
* @return q[VQ?b~9
* Returns the currentPage. l"E{ ?4
*/ }dzVwP=
publicint getCurrentPage(){ p?>J86%[
return currentPage; NZv 8#
} ~`&4?c3p
BHAFO E
/** |(*btdqy3
* @param currentPage I+;e#v,%U
* The currentPage to set. y>0 @.
*/ "lu^
publicvoid setCurrentPage(int currentPage){ y\;oZ]J
this.currentPage = currentPage; ^i#0aq2}
} #*qV kPX
6Aqv*<1=62
/** -XL?n/M
* @return =23B9WT
* Returns the everyPage. KTT!P 4
*/ BM:p)%Pv#P
publicint getEveryPage(){ Y\_mqd
return everyPage; l![79eFp
} F/lL1nTdK
CHv
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/** FT~c|ep.
* @param everyPage {$[0YRNk
u
* The everyPage to set. mfI[9G
*/ Bf00&PE;
publicvoid setEveryPage(int everyPage){ 2= ;ZJ
this.everyPage = everyPage; hfLe<,
} sj&(O@~R
r+[g.`
/** nbP}a?XC
* @return :KvZP:T
* Returns the hasNextPage. &$CyT6mb^
*/ ~s4JGV~R
publicboolean getHasNextPage(){ EH2):
return hasNextPage; @q<h.#9
} !gLJBp
}0E@eL
/** D[@-`F
* @param hasNextPage ,B/TqPP
* The hasNextPage to set. /G7^ l>pa
*/
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publicvoid setHasNextPage(boolean hasNextPage){ c/bT5TIEWs
this.hasNextPage = hasNextPage; C $])q`9
} (AZneK
:*
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/** / zNVJhC
* @return :/=P6b;
* Returns the hasPrePage. 4IfkYM
*/ w/o8R3F
publicboolean getHasPrePage(){ 9m>L\&\_e
return hasPrePage; Th%w-19,8
} lmoYQFkYP
|AvsT{2
/** ~!TrC<ft
* @param hasPrePage l>`S<rGe
* The hasPrePage to set. 8b,Z)"(U3
*/ >^9j>< Z
publicvoid setHasPrePage(boolean hasPrePage){ !lEV^SQJs
this.hasPrePage = hasPrePage; }.|a0N 5
} ZUB]qzmK
?UflK
/** !$iwU3~<
* @return Returns the totalPage. Z%.Ld2Q{
* x?{l<mc
*/ lxXF8c>U
publicint getTotalPage(){ 5C`Vno~v
return totalPage; H/x9w[\+[
} QrmGrRH
lp$,`Uz`
/** 6tVp%@
* @param totalPage e
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* The totalPage to set. DPnrzV)
*/ 0[ n;ZL~
publicvoid setTotalPage(int totalPage){ *yI( (G/
this.totalPage = totalPage; _%rkN0-(a
} E?K(MT&@
tx1TtWo
} _pS)bxw
d<\X)-"
+BI%.A`2
5 YIk
<Vyl*a{%
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 /*S6 /#
p0Ij4
个PageUtil,负责对Page对象进行构造: '#lEUlB
java代码: 3WkrG.$[b
Pvkr$ou
m7>)p]]
/*Created on 2005-4-14*/ 78Zb IL
package org.flyware.util.page; V^G+_#@,,
2+(SR.oGq
import org.apache.commons.logging.Log; "el3mloR8
import org.apache.commons.logging.LogFactory; %kBrxf
+@Kq
/** ]a~gnz&1
* @author Joa >]\oVG
* QE;,mC>
*/ Tt0]G_
publicclass PageUtil { SV2\vby}C
~ebm,3?
privatestaticfinal Log logger = LogFactory.getLog czo*_q%
/4*>.Nmb,f
(PageUtil.class); =cR=E{20
0F 4%Xz
/** A:sP%c;
* Use the origin page to create a new page v'y<}U
* @param page zq^eL=%:
* @param totalRecords OOus*ooo2
* @return !Cm9DzG
*/ .#e?[xxk
publicstatic Page createPage(Page page, int ug`Jn&x!
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totalRecords){ jA%R8hdr_
return createPage(page.getEveryPage(), .YS48 c
8`b_,(\ N
page.getCurrentPage(), totalRecords); _ =O;Lz$x
} :bp8S@
>Cr'dKZ}
/** ve/|"RB
* the basic page utils not including exception Z=s]@r
#k)J);&ZA
handler 8g_GXtn(z
* @param everyPage /Q9iO&Vu
* @param currentPage +r =p,leb
* @param totalRecords g9gyx/'*
* @return page Bd13p_V"6
*/ j =b-Y
publicstatic Page createPage(int everyPage, int ?0+J"FH# W
?B4X&xf.D
currentPage, int totalRecords){ Fmrl*tr
everyPage = getEveryPage(everyPage); :?gk=JH:
currentPage = getCurrentPage(currentPage); Q;p%
VQ
int beginIndex = getBeginIndex(everyPage, CM%;r5
+u7nx
currentPage); ^w}BXVn
int totalPage = getTotalPage(everyPage, %LdFS~
yD&UH_ 1g
totalRecords); AUkePp78
boolean hasNextPage = hasNextPage(currentPage, ,?!4P+ob
G-T2b,J
[
totalPage); uchz<z1
boolean hasPrePage = hasPrePage(currentPage); .sPa${
:+S~N)0j^
returnnew Page(hasPrePage, hasNextPage,
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everyPage, totalPage, -f[95Z3}
currentPage, M}F)
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#>\8m+h 9
beginIndex); I9r> 3?
} p8u-3
cf1GA
privatestaticint getEveryPage(int everyPage){ jJY!;f
return everyPage == 0 ? 10 : everyPage; a
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} W\yaovAt
=_dqoAF
privatestaticint getCurrentPage(int currentPage){ %MUwd@,
return currentPage == 0 ? 1 : currentPage; <~!R|5sK
} !Ry4w|w
*[['X%f
privatestaticint getBeginIndex(int everyPage, int }#f~"-O
baM@HpMhM
currentPage){ /3v`2=b
return(currentPage - 1) * everyPage; L[:b\O/p,
} 3/((7O[
< G:G/
privatestaticint getTotalPage(int everyPage, int ob.=QQQs
w!^{Q'/,Q
totalRecords){
PP)-g0^@
int totalPage = 0; iYxpIqWw
5PCKBevV
if(totalRecords % everyPage == 0) +q3E>K9a
totalPage = totalRecords / everyPage; Wd_KZ}lX
else lAPvphO
totalPage = totalRecords / everyPage + 1 ; L9)nRV8
vb Mv8Nk
return totalPage; ];o[Yn'>o
} ~~'UQnUN4
onAC;<w
privatestaticboolean hasPrePage(int currentPage){ Vnq&lz%QqC
return currentPage == 1 ? false : true; 8L*P!j9`EY
} CR<Nau>
_!*??B6u
privatestaticboolean hasNextPage(int currentPage, [8Zvs=1
ep2#a#&'
int totalPage){ #\fxU:z~r
return currentPage == totalPage || totalPage == VZArdXTP
f'<MDLl
0 ? false : true; hzjEO2
} I=I'O?w
k9<P]%
sC.aT(meJ
} ,s,VOyr @F
.-g++f(_i
#{kwl|c
|H'4];>R?
)tyhf(p6
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 IaLCWvHX
#A2)]XvY
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 jQiKof>
do1aH$Iw
做法如下: 2=6}! Y
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 IA XoEBlMs
80M"`6
的信息,和一个结果集List: eD4o8[s
java代码: *h>KeIB;
]D;X"2I2'b
P+~{q.|._c
/*Created on 2005-6-13*/ vA*Ud;%R
package com.adt.bo; MZX-<p+
}G#TYF}
import java.util.List; VSlIeZ
#JH#Qg
import org.flyware.util.page.Page; 26,!HmtC
&O5W
/** @sAT#[j
* @author Joa crt
)}L8-
*/ +JMB98+l
publicclass Result { ?m?DAd~ZY
02_%a1g
private Page page; #FBq8iJ
[BpIzhy&}
private List content; L+&eY?A
OXs-gC{b
/** c.u$NnDU6
* The default constructor wYrb P11
*/ m|)Mc VV
public Result(){ C[ ehw
super(); I'h6!N"
} t@TBx=16
'@ym-\,
/** w7?&eF(w(
* The constructor using fields R)3P"sGuN
* ^nYS@
* @param page ",c(cYVW
* @param content cboue
LEt
*/ H\\0V.}!
public Result(Page page, List content){ 8()L }@y
this.page = page; hDp
-,ag{
this.content = content; JwNG`MGc
} K>2mm!{
<303PPX^6
/** d+_wN2
* @return Returns the content. ,{ C
*/ "-'w,g
publicList getContent(){ LP8Stj JP
return content; #[^?f[9r
} v(?^#C>6W
)2|'`
/** aD aQ7i
* @return Returns the page. 0B^0,d(s
*/ CF`tNA3fxm
public Page getPage(){ ik@g; >pQD
return page; MVW2%6
} ]OE{qXr{
0jsU^m<g
/** 9OeY59
:
* @param content J
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* The content to set. >;N0( xB
*/ 3le/(=&1
public void setContent(List content){ H B+\2jEE
this.content = content; +)C?v&N
} QfuKpcT&
d~](S<k
/** @aU%1h5W;l
* @param page -'FzH?q:
* The page to set. .u3!%{/v(c
*/ wz-9+VN6
publicvoid setPage(Page page){ 0f).F
this.page = page; @;iW)a_M
} 6% @@~"
} }+KSZ,
n{dl-P
fLj#+h-!
t{\FV@R
TbqED\5@9w
2. 编写业务逻辑接口,并实现它(UserManager, bDa(@QJ-
#{)=%5=c
UserManagerImpl) =}Np0UP
java代码: )1%l$W
>5{Z'UWxh
Y%v?ROql
/*Created on 2005-7-15*/ `)`J
package com.adt.service; =.9L/74@
B w1ir
import net.sf.hibernate.HibernateException; Om%{fq&
LXr
yv;H
import org.flyware.util.page.Page; b
!FX]d1~k
`A8nAgbe
import com.adt.bo.Result; a"^0;a
*/iD68r|-
/** 1$Rua
* @author Joa =W(mZ#*vdY
*/ HS"E3s8
publicinterface UserManager { d'~
k f#
0z@KkU{Z
public Result listUser(Page page)throws a%"mgCB
'!*,JG5_
HibernateException; .lVC>UT
gWm
-}Nb4
} i1]*5;q
$Q,Fr;
B
} 5~|h%
`9a %vN
Fp>iwdjFg
java代码: h}&WBN
\F;V69'
,bh OIuep3
/*Created on 2005-7-15*/ fZK&h.
package com.adt.service.impl; ezRhSN?
(H/JB\~r
import java.util.List; pi)7R:i
w%jc' ;|
import net.sf.hibernate.HibernateException; %N#8D<ULd
lP*_dt9
import org.flyware.util.page.Page; Y4cIYUSc
import org.flyware.util.page.PageUtil; x8I=I"Sp
4LqJ4jo
import com.adt.bo.Result; ?-CZJr
import com.adt.dao.UserDAO; {-*+G]
import com.adt.exception.ObjectNotFoundException; (Zi(6 T\z
import com.adt.service.UserManager; SoZ$1$o2
Mg?^ 5`*
/** cn&\q.!fh
* @author Joa ]~g6#@l
*/ !+tz<9BBY
publicclass UserManagerImpl implements UserManager { m\>531&
U)~?/s{v
private UserDAO userDAO; zPWX%1Qr
C$o#zu q-
/** ydo"H9NOS
* @param userDAO The userDAO to set. qgd#BJ=
*/ u_[^gS7
publicvoid setUserDAO(UserDAO userDAO){ /QDlm>FM4
this.userDAO = userDAO; 5$o]D
} }oHA@o5
'@)47]~
/* (non-Javadoc) <11pk
* @see com.adt.service.UserManager#listUser UxI0Of&:
[MfKBlA
(org.flyware.util.page.Page) ,7:_M>-3g
*/ qkB)CY7
public Result listUser(Page page)throws PjriAlxD
ea-NqdGs;m
HibernateException, ObjectNotFoundException { @vWf-\
int totalRecords = userDAO.getUserCount(); ?0_Bs4O\
if(totalRecords == 0) mo1(dyjx
throw new ObjectNotFoundException } LLnJl~Z
B. Rc s
("userNotExist"); p!^.;c
page = PageUtil.createPage(page, totalRecords); 2 2K:[K
List users = userDAO.getUserByPage(page); DJ?kQ
returnnew Result(page, users); 8s6~l.v
} r8\"'4B1
`9QvokD
} ad^7t<a}<
\a]JH\T)Q
bl. y4
eekp&H$'s
rb_ cm
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 CAg\-*P|
l]Ozy@
Ib
询,接下来编写UserDAO的代码: =KfV;.&
3. UserDAO 和 UserDAOImpl: m1DzUq;
java代码: :A%|'HxH3
vJ96qX
|0 #J=am
/*Created on 2005-7-15*/ [iE% P^
package com.adt.dao; !~5;Jb>s[/
&6%%_Lw$
import java.util.List; 1 FTxbw@
-QR&]U+
import org.flyware.util.page.Page; _^cDB1I?
49b#$Xq
import net.sf.hibernate.HibernateException; &|( 'z\k
6u>${}
/** bQG2tDvu[
* @author Joa D 3m4:z
*/ \tf \fa
publicinterface UserDAO extends BaseDAO { &oJ=
KKm&~^c
publicList getUserByName(String name)throws wYnsd7@I
4$Oakl*l
HibernateException; m89-rR:Kc
uJ jm50R<
publicint getUserCount()throws HibernateException;
nb}* IExd
+*"u(7AV
publicList getUserByPage(Page page)throws .6Jo1$+
V_pWf5F
HibernateException; 3vx*gfr3
^CZ!rOSv
} (jYHaTL6Y'
28qTC?
@,
v'V!
(`+%K_
II$B"-
java代码: #({0HFSC:j
ZuIr=`"j
Vae}:8'}
/*Created on 2005-7-15*/ 8>" vAEf
package com.adt.dao.impl; X`kTbIZ|
3|4jS"t{f
import java.util.List; ta`}}I
0M^7#),
import org.flyware.util.page.Page; _[ml<HW]
f0rM 4"1
import net.sf.hibernate.HibernateException; ^_FB .y%
import net.sf.hibernate.Query; {+~}iF<%
;Z]i$Vi_r
import com.adt.dao.UserDAO; TVVL1wZ
9\9:)q
/** w"Gci~]bXU
* @author Joa tU2 8l.
*/ /wplP+w2
public class UserDAOImpl extends BaseDAOHibernateImpl G gmv(!
HGqT"NJr
implements UserDAO { R;+vE'&CO
??&Q"6Oe
/* (non-Javadoc) &2-dZK
* @see com.adt.dao.UserDAO#getUserByName P]]re,&R
jOL $kiW0
(java.lang.String) aO:wedfl
*/ +3]1AJa
publicList getUserByName(String name)throws H_gY)m
MVdX
HibernateException { $X1T!i[.X
String querySentence = "FROM user in class 8Jnb/A}
x6Q,$B
com.adt.po.User WHERE user.name=:name"; r;}%} /IX
Query query = getSession().createQuery LIfQh
Ne7HPSWiOP
(querySentence); =7{n 2
query.setParameter("name", name); WGwpryaya
return query.list(); v x qsK
} eXo7_#
d:08@~#
/* (non-Javadoc) ]PWK^-4P
* @see com.adt.dao.UserDAO#getUserCount() F+yu[Dh:
*/ DC?U+
publicint getUserCount()throws HibernateException { u#9 H
int count = 0; tkT:5O6
String querySentence = "SELECT count(*) FROM zN2CI6
~qFuS933
user in class com.adt.po.User"; gaFOm9y.e
Query query = getSession().createQuery ?N*m2rv
E=
3Ui
(querySentence); BYj Eo
count = ((Integer)query.iterate().next | Q0Wv8/
qffVF|7
()).intValue(); 3 !W
M'i
return count; CK4C:`YG
} TmI~P+5w
FbH
1yz
/* (non-Javadoc) VK>ZH^-
* @see com.adt.dao.UserDAO#getUserByPage QD6<sw@]P
~z;G$jd
(org.flyware.util.page.Page) h-)tWJ c
*/ 'ii5pxeNI
publicList getUserByPage(Page page)throws S\$=b_.
x-0O3IIE
HibernateException { tzH~[n,
String querySentence = "FROM user in class pC=kv ve
WC2sRv4]3
com.adt.po.User"; yU ?TdM\
Query query = getSession().createQuery hnOo T? V
0\W6X;?
(querySentence); A7U]wW9
query.setFirstResult(page.getBeginIndex())
g!/O)X3
.setMaxResults(page.getEveryPage()); Ife/:v
return query.list(); >@Vap
} =i'APeNaQ
o$PY0~#
} Sfl. &A(
>;wh0dBe
o:oQF[TcFO
*@;Pns]L-
lVb{bO9-O
至此,一个完整的分页程序完成。前台的只需要调用 {tE9m@[AF
CKB~&>xx
userManager.listUser(page)即可得到一个Page对象和结果集对象 &E&_Z6#
[g<rzhC~=
的综合体,而传入的参数page对象则可以由前台传入,如果用 }
O:Y?Wq^
ks3ydHe`
webwork,甚至可以直接在配置文件中指定。 B!J~ t8
3^!Y9$y1
下面给出一个webwork调用示例: '! \t!@I$
java代码: tk]>\}%
1}=@';cK*
x-E@[=
/*Created on 2005-6-17*/ 4$~A%JN3
package com.adt.action.user; m$XMq
TwdY6E3`
import java.util.List; Hl"^E*9x
)4O>V?B
import org.apache.commons.logging.Log; W}6OMAbsE;
import org.apache.commons.logging.LogFactory; (U`<r-n\n
import org.flyware.util.page.Page; j Wpm"C
Vt4KG+zm
import com.adt.bo.Result; G;jX@XqZ
import com.adt.service.UserService; ;T-`~
import com.opensymphony.xwork.Action; i#4}xvi
l% \p
/** $I*<gn9
* @author Joa w20)~&LE-
*/ $?Dcp^
publicclass ListUser implementsAction{ J 2H$ALl
rt8"U<~
privatestaticfinal Log logger = LogFactory.getLog NuEcTww
uT#4"G9A[
(ListUser.class); y=HM]EH>
%]"eN{Uvn
private UserService userService; n{*A<-vL
{JGXdp:SB
private Page page; #[odjSb
$j(laD#AR
privateList users; }.L:(z^L,Y
m#Y[EPF=|
/* WALK@0E
* (non-Javadoc) '&LH9r
* >~}}*yp
* @see com.opensymphony.xwork.Action#execute() u2o196,Ut
*/ TxA%{0
publicString execute()throwsException{ ;{j@ia
Result result = userService.listUser(page); DeK&_)g| Z
page = result.getPage(); OCN:{
users = result.getContent(); r]3v.GZy
return SUCCESS; "wi}/,)
} prw% )#,
,DIr&5>p2
/** 'hNRIM1
* @return Returns the page. V*,6_-^l
*/ nN'>>'@>
public Page getPage(){ p3Z[-2I
return page; O-uf^S4
} #&sw%CD
boeIO\2}P0
/** kN g{
* @return Returns the users. INNTp[
*/ WQ1K8B4
publicList getUsers(){ bMGU9~CeJ
return users; 6[T)Q ^0`
} Ue&I]/?;$
|Duf
3u
/** EUmbNV0u
* @param page %) /Bl.{}<
* The page to set. 70F(`;
*/ ?
4v"y@v
publicvoid setPage(Page page){ __Egr@
this.page = page; gg?O0W{
} GswV/V+u
p?,T%G+gqO
/** N"Cd{3
* @param users $wm8N.I3I
* The users to set. K<vb4!9Z9
*/ LTZ~Id-)P
publicvoid setUsers(List users){ j&l2n2z
this.users = users; )Im3';qt
} _edT+r>+
2#_i_j
/** q^Ui2
* @param userService g{e@I;F
* The userService to set. %df[8eX{
*/ >>.4@
publicvoid setUserService(UserService userService){ #gSIa6z1W
this.userService = userService; F* _ytL
} >jRH<|Az
} f^[u70c82
A3A"^f$$
rrrn8b6
#@Rtb\9
'/GZ/$a_l
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, 0czEA
ia*Bcx_RW+
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 h,x'-]q
=SK{|fBB
么只需要: *kq>Z 06'i
java代码: ' p!\[*e
W@WKdaJ
Ey]P
>J
<?xml version="1.0"?> i{MzQE+_^
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork pIgjo>K
f}:W1&LhI?
1.0//EN" "http://www.opensymphony.com/xwork/xwork- W~?mr!`
Stk'|-z
1.0.dtd"> zuYz"-(L
x}7` Q:k=
<xwork> - -ZSl
87OX:6
<package name="user" extends="webwork- 2X`5YN;
nD!5I@D
interceptors"> te
b/
e$4$G<8;y
<!-- The default interceptor stack name ~IS3i'bh
;hkzL_' E)
--> ;#n+$Q#:
<default-interceptor-ref L=)Arj@q
X0BBJ( e
name="myDefaultWebStack"/> R zn%!d^$>
Pi'[d7o
<action name="listUser" Sz0CP1WB
c n^z=?
class="com.adt.action.user.ListUser"> u= ydX
<param o0FVVS l
u;H5p\zAzz
name="page.everyPage">10</param> :eL
ja*
<result +*Pj,+;W
5tcJTz
name="success">/user/user_list.jsp</result> >OW>^%\!1
</action> .WpvDDUK3
Y5\=5r/
</package> 0RkiD8U5
=Y<RG"]a&J
</xwork> nhI1`l&
7gP8K`w?[
t(\P8J
3vRBK?Q.y
t'DYT"3
)/4U]c{-
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 wf/DLAC
g/jlG%kI}
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。 '/Ag3R
]?n~?dD{]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 j[&C6l+wH
=7 ${bp!
p'YNj3&u
zH1:kko
IWP[?U=
我写的一个用于分页的类,用了泛型了,hoho =J827c{.
Y]9C 8c)
java代码: 50Y^##]&
\"AzT{l!;
)d"s6i
package com.intokr.util; ` EgO&;1D)
`ILO]+`5
import java.util.List; :yE7jXB
}@NT#hD
/** MP%pEUomev
* 用于分页的类<br> 07qL@![!
* 可以用于传递查询的结果也可以用于传送查询的参数<br> W6L}T,epX
* $+Zj)V(
* @version 0.01 N83g=[
* @author cheng -A;4""
*/ '(&,i/O
public class Paginator<E> { 2:Rxyg@'
privateint count = 0; // 总记录数 }q<%![%
privateint p = 1; // 页编号 0\Ga&Q0-(O
privateint num = 20; // 每页的记录数 <O30X
!QuK
privateList<E> results = null; // 结果 E@D}Sqt
q3$;lLsb;j
/** q? 2kD"%$
* 结果总数 @Yy']!Ju
*/ ["
nDw<U
publicint getCount(){ ?R\:6x<
return count; ]Q*eCt;l"K
} Sp^jC
Xu
&~a/Upz0]_
publicvoid setCount(int count){ 6/&aBE=
this.count = count; Ialbz\;F2%
} )R]gJ_,c
_.G p}0a
/** q+}Er*r
* 本结果所在的页码,从1开始 BHEZ<K[U
* o7WK"E!pF'
* @return Returns the pageNo. b.sRB1
*/ bsgr g
publicint getP(){ p@bcf5'
return p; #+6t|
} T!pjv8y@R
{ 0vHgi
/** eE-c40Bae
* if(p<=0) p=1 (v$$`zh
* 1pHt3Vc(G
* @param p h!UB#-
*/ /ng+IC3
publicvoid setP(int p){ u=9)A9
if(p <= 0) _Vf0MU;3f+
p = 1; bRb+3au_x
this.p = p; ~f:jI1(}
} .*+KQA8
=x3ZQA
/** E#A}J:
* 每页记录数量 #(Ah>y
*/ |"XxM(Dm
publicint getNum(){ E2a00i/9Y
return num; 1X$hwkof
} _;yi/)-2
cp\A
xWtUZ
/** 2h^9lrQcQG
* if(num<1) num=1 H&3i[D!p
*/ {9yW8&m
publicvoid setNum(int num){ Z2wgfP`
if(num < 1) A3=$I&!%
num = 1; t:<dirw,o
this.num = num; f*Dy>sw
} |)\{Rufb
4_B1qN
/** &*r'Sx)V
* 获得总页数 b&~s}IX
*/ T6=q[LpsKN
publicint getPageNum(){ P-~kxb9aa
return(count - 1) / num + 1; Lm}J&^>
} eFiUB
&@anv.D
/** G,6Zy-Y9
* 获得本页的开始编号,为 (p-1)*num+1 O.g!k"nas&
*/ -F+dmI,1$
publicint getStart(){ 7TW</g(
return(p - 1) * num + 1; 3(/J(8
} Hjtn*^fo^
,F)9{ <r]
/** t)hAD_sf
* @return Returns the results. :Kt'Fm,s?
*/ hB:}0@l6p=
publicList<E> getResults(){ 9V5d=^
return results; K)d]3V!
} <R>%DD=v^
rBY{&JhS
public void setResults(List<E> results){ 2UGnRZ8:1Y
this.results = results; uqMe%
} 5Sm)+FC:
zjVQ \L
public String toString(){ !04zWYHo
StringBuilder buff = new StringBuilder !<P|:Oo*Dl
E6FT*}Q
();
mtQlm5l
buff.append("{"); = g[Cs*
buff.append("count:").append(count); bEz1@"~
p
buff.append(",p:").append(p); c7fQ{"f 3B
buff.append(",nump:").append(num); <.lT.>'?
buff.append(",results:").append <#r/4a"V
[V-OYjPAx
(results); ao(lj
buff.append("}"); |{G GATni
return buff.toString(); }F~4+4B^
} mm,be.
ZXR#t?D
} `43X? yQ
lIlmXjL0
R^*h|7)E