Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 mHEf-6|C`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Dp*$GQ
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 _7#tgZyv
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 CSL{Q
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。 oCKM5AVWsv
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分页支持类: jfY{z=*]u
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java代码: ytve1<.Ff
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package com.javaeye.common.util; .FKJyzL
.i+* #djx
import java.util.List; U$A7EFK'
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publicclass PaginationSupport { ;>Ca(Y2M
7SK3
publicfinalstaticint PAGESIZE = 30; Aa`MK$29F
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privateint pageSize = PAGESIZE; !b7'>b'J<1
~n/Aq*
privateList items; 2>$F0
M
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privateint totalCount; ^S#\O>GHP
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privateint[] indexes = newint[0]; e?!L}^f6X
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privateint startIndex = 0; _V& !4Zd9:
p?V?nCv1O
public PaginationSupport(List items, int feI./E
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,{ _
totalCount){ TX23D)CX
setPageSize(PAGESIZE); }Kj Ju;
setTotalCount(totalCount); m
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setItems(items); ;}/U+`=D?
setStartIndex(0); AfRW=&xdT
} *K(k Kph
x6^l6 N
public PaginationSupport(List items, int <&5m N
X(k{-|9]
totalCount, int startIndex){ )N"Ew0U
setPageSize(PAGESIZE); U@6jOZ
setTotalCount(totalCount); fB~O
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setItems(items); bVoU|`c
setStartIndex(startIndex); %9C`
} S]&8St
jt{9e:2%
public PaginationSupport(List items, int |h&<_9
qoj^_s6
totalCount, int pageSize, int startIndex){ -<qxO
setPageSize(pageSize); 7]Al*)
setTotalCount(totalCount); p%q.*trUb9
setItems(items); x\hWyY6J[
setStartIndex(startIndex); 7} be>(
} AF^T~?t
.'|mY$U~]
publicList getItems(){ KRYcCn
return items; yu)q4C7ek
} Ji;SY{~kv
?Z q_9T7
publicvoid setItems(List items){ Sd},_Kh
this.items = items; q|5Q?t:,r
} *>jjMy n
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publicint getPageSize(){ "EoDQT"0
return pageSize; k$h [8l(<
} H@{Objh1
'\`6ot8
publicvoid setPageSize(int pageSize){ !(Krf
this.pageSize = pageSize; !
ja[4.
} /aZE,IeEz
Sp:l;SGd
publicint getTotalCount(){ v*SAI]{#~
return totalCount; jM~Bu.7 i6
} rH&G<o&,
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publicvoid setTotalCount(int totalCount){ Py|;kF~! [
if(totalCount > 0){ 845
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this.totalCount = totalCount; ,CciTXf
int count = totalCount / ?aBj#
%}q.cV
pageSize; xCWz\-;
if(totalCount % pageSize > 0) m9$ a"$c
count++; x4m 5JDC
indexes = newint[count]; fc@'9-pt
for(int i = 0; i < count; i++){ M;+IZr Wkl
indexes = pageSize * ju|]Qlek
c%z'xM
i; 22
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} s)zJT
}else{ a(;!O}3_)(
this.totalCount = 0; TBCp
L]QT
} lCJ6Ur;
} zI^]esX!2_
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publicint[] getIndexes(){ F; 8*H1
return indexes; h7]EB!D\A
} @PI%FV z~p
v4rW2F:X
publicvoid setIndexes(int[] indexes){ 5G[x }4U
this.indexes = indexes; dRW$T5dac
} +5!&E7bcd
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publicint getStartIndex(){ fE]XWA4U
return startIndex; Vi?q>:E:
} Es!Q8.
KkcXNjPVS
publicvoid setStartIndex(int startIndex){ /vxm"CJR
if(totalCount <= 0) r^0F"9eOL
this.startIndex = 0; k7@t{Cu0D&
elseif(startIndex >= totalCount) ]y#3@
this.startIndex = indexes /( hUfYm0
t~``md4
[indexes.length - 1]; t$J.+} }I
elseif(startIndex < 0) OhVs#^
this.startIndex = 0; %eg+F
else{ c9wfsapJ
this.startIndex = indexes .ubE2X[ ][
0hY{<^"Y
[startIndex / pageSize]; 15U (={
} s58C2
} Ts.wh>`
ea'&xs#GK
publicint getNextIndex(){ aNxAZMg
int nextIndex = getStartIndex() + <\ `$Jx#
pav'1d%
pageSize; PPkx4S_>
if(nextIndex >= totalCount) z^<L(/rg9"
return getStartIndex(); /w (e
else :,B7-kBw
return nextIndex; s{0aBeq
} -fS.9+k0/
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publicint getPreviousIndex(){ vi.w8>CE
int previousIndex = getStartIndex() - ;&V s4
ntFT>g{B
pageSize; /D!;u]
if(previousIndex < 0) ZJPmR/OV_
return0; ]:>,A@7
else d?wc*N3
return previousIndex; f| _u7"OX
} d.UQW
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} =X\^J
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抽象业务类 ?;[w" `"
java代码: ktIi$v
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/** }\J2?Et{
* Created on 2005-7-12 ^8.]d~j
*/ /xtq_*I1S
package com.javaeye.common.business; q$I:`&
1-lu\"H`
import java.io.Serializable; Pj}66.
import java.util.List; ,]bB9tid
{~Rk2:gx
import org.hibernate.Criteria; ~e6Brq
import org.hibernate.HibernateException; h1'\:N`
import org.hibernate.Session; '!/<P"5t
import org.hibernate.criterion.DetachedCriteria; 6DH~dL_",%
import org.hibernate.criterion.Projections; d3=KTTi\
import %CK^Si%+
u\C
lP#
org.springframework.orm.hibernate3.HibernateCallback; feQ **wI
import PLK3v4kVM!
/~zai}
org.springframework.orm.hibernate3.support.HibernateDaoS J0@X<Lt U
oYukLr
upport; 8F'x=lIO
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import com.javaeye.common.util.PaginationSupport; ."9];)2rx
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public abstract class AbstractManager extends Ytl4kaYS
V$ps>
HibernateDaoSupport { .ev?"!Vpp9
V,%=AR5
privateboolean cacheQueries = false; r-Pkfy(
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privateString queryCacheRegion; RJd(~1
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publicvoid setCacheQueries(boolean abyo4i5T
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cacheQueries){ A<??T[
this.cacheQueries = cacheQueries; "hsb8-
} Fvbh\m
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publicvoid setQueryCacheRegion(String t+!$[K0/
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queryCacheRegion){ EwvoQ$#jv
this.queryCacheRegion = 9po3m]|zy
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queryCacheRegion; uC(V
} )8$=C#qC[
gcl5jB5)>
publicvoid save(finalObject entity){ OWg(#pZk
getHibernateTemplate().save(entity); &7K?w~
} 2QyV%wz
A;]}m8(*
publicvoid persist(finalObject entity){ nH[yJGZYSA
getHibernateTemplate().save(entity); h eV=)8
} -C(crn
:%,:"
publicvoid update(finalObject entity){ ?iWi
getHibernateTemplate().update(entity); 0"28'
} ).`1+b
3 cK I
publicvoid delete(finalObject entity){ n'E(y)9|
getHibernateTemplate().delete(entity); s;01u_
} EVsC >rz
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publicObject load(finalClass entity, ix)M`F%P3
q_MG?re
finalSerializable id){ kuszb~`zPY
return getHibernateTemplate().load P2#XKG
uxvqMgR
(entity, id); QI'Oz{vE
} $5aV:Z3P
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publicObject get(finalClass entity, qNB<T('
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finalSerializable id){ FWrX3i
return getHibernateTemplate().get n|9-KTe7|*
a|t$l=|DD
(entity, id); sBvzAVBL
} Vc&!OE
f
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publicList findAll(finalClass entity){ u8&Z!p\
return getHibernateTemplate().find("from i&bA2p3+d
fg_4zUGM+g
" + entity.getName()); %Nlt H/I
} GfoLae
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publicList findByNamedQuery(finalString x<tb
+Vb.lH[av
namedQuery){ PUT=C1,OFR
return getHibernateTemplate %g{X ?
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().findByNamedQuery(namedQuery); #L=x%8B
} >JHryS.j$4
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publicList findByNamedQuery(finalString query, %(3|R@G.
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finalObject parameter){ ?uzRhC_)!
return getHibernateTemplate 36}?dRw#p
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().findByNamedQuery(query, parameter); 'f!8DGix
} (-UYB9s
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publicList findByNamedQuery(finalString query, MU@UfB|;u
n\Z!ff/
finalObject[] parameters){ ! `
return getHibernateTemplate h5*JkRm
lk/n}bx
().findByNamedQuery(query, parameters); 0fb2;&pUa
} W#9BNKL
+nrbShV
publicList find(finalString query){ g0xuxK;9c
return getHibernateTemplate().find l%k\JY-
{j.bC@hWw
(query); cM(:xv
} >,V9H$n
? &o2st
publicList find(finalString query, finalObject ~Z\8UsVN
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parameter){ LM:vsG
return getHibernateTemplate().find ~^NtO
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(query, parameter); ~8'sBT
} dN$0OS`s[
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public PaginationSupport findPageByCriteria Go5J%&E9
Q- cFtu-w
(final DetachedCriteria detachedCriteria){ {{$Nqn,pH
return findPageByCriteria -o^7r@6
l.67++_
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8zZvht*
} du<tGsy
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public PaginationSupport findPageByCriteria .p<:II:6
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(final DetachedCriteria detachedCriteria, finalint %|s; C
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startIndex){ Ot4 Z{mA
return findPageByCriteria u0JB\)(-/h
P{8iJ`rBG
(detachedCriteria, PaginationSupport.PAGESIZE, |UkR'Ma
3atBX5
startIndex); Kr?TxhUHd
} Zd3S:),&
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public PaginationSupport findPageByCriteria 'j`=if
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(final DetachedCriteria detachedCriteria, finalint e),q0%5
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pageSize, 4V{:uuI;f
finalint startIndex){ ty8q11[8
return(PaginationSupport) 216 RiSr*
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getHibernateTemplate().execute(new HibernateCallback(){ mUNn%E:7@{
publicObject doInHibernate +jAGGv^)
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(Session session)throws HibernateException { Q7HRzA^-
Criteria criteria = ST|x23|O]
R}-(cc%5
detachedCriteria.getExecutableCriteria(session); %41m~Wh2
int totalCount = >"??!|XG^
>Rl"
((Integer) criteria.setProjection(Projections.rowCount 0.\/\V:H6
h\$$JeSV]
()).uniqueResult()).intValue(); ?fQ'^agq
criteria.setProjection &u]8IEv}u
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(null); )cW#Rwu_A4
List items = qFicBpB
XD!W: uvb
criteria.setFirstResult(startIndex).setMaxResults 034iK[ib"
Wvq27YK'
(pageSize).list(); )Oq|amvC
PaginationSupport ps = S){)Z
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new PaginationSupport(items, totalCount, pageSize, s,"]aew
]V[q(-Jk
startIndex); l^!
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return ps; D.r<QO~6B
} fnpYT:%fG
}, true); |O{m2Fi
} _jvxc'6
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public List findAllByCriteria(final '@a}H9>}
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DetachedCriteria detachedCriteria){ Bm:98? [
return(List) getHibernateTemplate dhC$W!N7!
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().execute(new HibernateCallback(){ Vouvr<43o
publicObject doInHibernate v>6"j1Z
jqz ux[6{
(Session session)throws HibernateException { bYcV$KJk
Criteria criteria = bc7/V#W
3>3 Kwc~E
detachedCriteria.getExecutableCriteria(session); |sa]F5
return criteria.list(); kF3k7,.8&
} ,xw#NG6
}, true); Mhm@R@
} ;p.v]0]is
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public int getCountByCriteria(final vXev$x=w-
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q\p
DetachedCriteria detachedCriteria){ k}S :RK
Integer count = (Integer) >|J`s~?
j SHk{T!J
getHibernateTemplate().execute(new HibernateCallback(){ 2_)\a(.Qu
publicObject doInHibernate Ah1]Y}sy
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(Session session)throws HibernateException { BfXgh'Z~
Criteria criteria = {5A2&
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detachedCriteria.getExecutableCriteria(session); yyR0]NzYUD
return ;^+\K-O]c
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criteria.setProjection(Projections.rowCount 6S},(=
}?lrU.@zg
()).uniqueResult(); 1kz\IQ{
} %J#YM'g
}, true); ;$HftG>B
return count.intValue(); ;:iY) }
} } j<)L,
} 4d"r^y'
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用户在web层构造查询条件detachedCriteria,和可选的 *F WMn.
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9y6-/H
,
q$p%ZefZ
PaginationSupport的实例ps。 [<7@{;r
FSP+?((
ps.getItems()得到已分页好的结果集 #:jHp44J
ps.getIndexes()得到分页索引的数组 A_V]yP
ps.getTotalCount()得到总结果数 DP[IZC
ps.getStartIndex()当前分页索引 <5d~P/,
ps.getNextIndex()下一页索引 ksc;X$f&4
ps.getPreviousIndex()上一页索引 ?U%QG5/>
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 +j#+8Ze
.rO]M:UY
,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 .RE:;<|w
\?w2a$?6w
一下代码重构了。 %]Fd[pzF
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我把原本我的做法也提供出来供大家讨论吧: &[_g6OL
Z.c'Hs+;
首先,为了实现分页查询,我封装了一个Page类: f6EZ(
v
java代码: yu;+o3WlK
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bhID#&
/*Created on 2005-4-14*/ +Um( h-;
package org.flyware.util.page; >x/z7v?^I
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/** 9l|@v=gw.
* @author Joa |)nZ^Cc
* D~biKrg?=
*/ *Tas`WA
publicclass Page { >5_2_Y$"
+vvv[
/** imply if the page has previous page */ KmMzH`t}`
privateboolean hasPrePage; 0f~C#/[t7
%9w::hav
/** imply if the page has next page */ b+,';bW
privateboolean hasNextPage; f) zn TJL
VkvB<3
/** the number of every page */ 9Kpa><
privateint everyPage; PbW(%7o(t
(XeE2l2M
/** the total page number */
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privateint totalPage; n\QgOSr<
GU4'&#
/** the number of current page */ ~KHVY)@P
privateint currentPage; Hx#;Z
S)lkz'tdk
/** the begin index of the records by the current %4ePc-
H!?c\7adX
query */ 5XO;N s
privateint beginIndex; lU@]@_<
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D6%J\C13`
/** The default constructor */ 0>C T=(A
public Page(){ p qfUW+>
<PapskO>
} ;hYS6
j2ve^F:Q
/** construct the page by everyPage >{N9kWY
* @param everyPage 6""G,"B
* */ cJN7bA{
public Page(int everyPage){ %JXE5l+pJ
this.everyPage = everyPage; QOjqQfmM;
} { D^{[I
^oVs+ vC
/** The whole constructor */ " 7!;KHc
public Page(boolean hasPrePage, boolean hasNextPage, )T';qm0w
cVubb}ou
aEM %R<e
int everyPage, int totalPage, iJ~Zkd
int currentPage, int beginIndex){ +g` 'J$
this.hasPrePage = hasPrePage; WP?TX b`5
this.hasNextPage = hasNextPage; uv=.2U46
this.everyPage = everyPage; #1`-*.u
this.totalPage = totalPage; "{tg8-a4)
this.currentPage = currentPage; TatpXN\
this.beginIndex = beginIndex; f47Od-\-
} OZx
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IOb*GTb
/** ,RJtm%w
* @return T,]7ICF#
* Returns the beginIndex.
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*/ %1H[Wh(U
publicint getBeginIndex(){ q<\,
return beginIndex; /e7O$L)
} ~KW,kyXBnD
;ado0-VQi'
/** `&KwtvkdI
* @param beginIndex X}tVmO?
* The beginIndex to set. e?opkq\f
*/ `wus\&!W
publicvoid setBeginIndex(int beginIndex){ F{EnOr`,m=
this.beginIndex = beginIndex; OlAs'TE^
} U 'R)x";=
KHgBo}6
/** >}!mQ pAO
* @return 0o+6Q8q
* Returns the currentPage. 29!q!g |
*/ @c<3b2
publicint getCurrentPage(){ RnhL<
Ywu
return currentPage; +)j$|x~(A
} Rn{iaM2Y<
sA'6ty
/** )6+eNsxMlC
* @param currentPage 11<Qxu$rL
* The currentPage to set. #Yr9AVr}K
*/ .Jt[(;
publicvoid setCurrentPage(int currentPage){ R$[#+X!
this.currentPage = currentPage; mMb'@
} P5
K' p5}#
Ys,{8Y,7
/** KcK>%%
* @return #bl6sa{E
* Returns the everyPage. )=AHf?hn
*/ GFel(cx:K
publicint getEveryPage(){ }RHn)}+
return everyPage; `FYv3w2
} } p&&_?
blTo5NLX
/** NR -!VJQ
* @param everyPage 7N:Y?Hi\
* The everyPage to set. F8;dKyT?q
*/ SzUpWy&
publicvoid setEveryPage(int everyPage){ 7b<je=G6PA
this.everyPage = everyPage; <Wp
QbQM
} gF$V$cU
WAn~+=Ax
/** =0G!f$7^i
* @return du)~kU>l
* Returns the hasNextPage. yil[gPy4B
*/ _T2=J+"-Kp
publicboolean getHasNextPage(){ 'bo~%WA]n
return hasNextPage; Kj<^zo%w
} 1RK=,Wx
sFQ^2PwbS
/** -5T=:2M
* @param hasNextPage )hk
* The hasNextPage to set. B<~ NS)w
*/ Q8DQlqHm
publicvoid setHasNextPage(boolean hasNextPage){ qUxRM_7U
this.hasNextPage = hasNextPage; co9 .wB@
} 9nH?l{As
#Sa27$&.>
/** !zPa_`P
* @return .!G94b
* Returns the hasPrePage. )l!3(
*/ (HSgEs1d
publicboolean getHasPrePage(){
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return hasPrePage; # g_Bx
} !OT-b>*w
ap{2$k ,
/** '3<fsK=
* @param hasPrePage v>Mnl
* The hasPrePage to set. z,VD=Hnz
*/ u-tQ9ioKC
publicvoid setHasPrePage(boolean hasPrePage){ 4E+hRKuo,
this.hasPrePage = hasPrePage; ^`G`phd$
} Tp0bS
] Puy!Q
/** i:Zm*+Gi
* @return Returns the totalPage. Fr%d}g
* :"l-KQ0
*/ ND5`Q"k
publicint getTotalPage(){ vmLxkjUm#
return totalPage; y|Ir._bt
} mWyqG*-Hb
;>AL`M+
/** #hlCs
* @param totalPage ^qC;Nh4F
* The totalPage to set. *bxzCI7b
*/ Dc+'<"
publicvoid setTotalPage(int totalPage){ HU9Sl*/
this.totalPage = totalPage; JXw^/Y$
} 3LfC{ER
o ,xxh
} 9
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s
bcAvM;
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6:]*c[7
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 e#B#B
9{$'S4
个PageUtil,负责对Page对象进行构造: B}eA\O4}I
java代码: /'hC i]b@v
m~>Y{F2
b]7GmRekl
/*Created on 2005-4-14*/ $z$u{
package org.flyware.util.page; @rHK(25+d
t!2(7=P30(
import org.apache.commons.logging.Log; >+mD$:L
import org.apache.commons.logging.LogFactory; Qjnd6uv{I
k2xHH$+{#=
/** 'oN\hy($,h
* @author Joa >5wx+n)/)
* RID]pek
*/ IQ!\w-
publicclass PageUtil { .c#y%S
]7Fs$y.
privatestaticfinal Log logger = LogFactory.getLog } %'bullT
c,Euv>*`
(PageUtil.class); o0ZM[0@j
=0-
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/** unJ R=~E
* Use the origin page to create a new page UYA_jpI P
* @param page 1.D-FPK
* @param totalRecords 4G@nZn
* @return c!hwmy;
*/ {ls+dx/
publicstatic Page createPage(Page page, int IG?'zppjd6
yIb,,!y9{
totalRecords){ +f0~D(d!_
return createPage(page.getEveryPage(), 5[{*{^F4
7n o5b]
\
page.getCurrentPage(), totalRecords); ^>?CMcN4*
} S?{/hy
=H8 xSJLh
/** L'i-fM[#
* the basic page utils not including exception IZ3{>NV
dx,=Rd5'
handler `O^G5 0
* @param everyPage XCsiEKZ_i
* @param currentPage O g%U
* @param totalRecords Sb".]>^
* @return page jxgj,h"}9`
*/ zNSu
publicstatic Page createPage(int everyPage, int %~NH0oFO
Zc"B0_&?:7
currentPage, int totalRecords){ K~RoUE<3[
everyPage = getEveryPage(everyPage); QHBtWQgS
currentPage = getCurrentPage(currentPage); OndhLLz
int beginIndex = getBeginIndex(everyPage, k#}g,0@
x\s,= n3z
currentPage); hIJ)MZU|
int totalPage = getTotalPage(everyPage, iv(5&'[p
'z=:[#b
totalRecords); ]+DI.%
boolean hasNextPage = hasNextPage(currentPage, ExHAY|UA
=\,
qP
totalPage); vQ@2FZzu>
boolean hasPrePage = hasPrePage(currentPage); s,*c@1f?
]>i~6!@
returnnew Page(hasPrePage, hasNextPage,
,%#
everyPage, totalPage, >i,iOx|E-
currentPage, !.5),2
4\
/*jA
beginIndex); Cup@TET35
} ?lCd{14Mkh
|4Ck;gg!j
privatestaticint getEveryPage(int everyPage){ (y4#.vZh:
return everyPage == 0 ? 10 : everyPage; Fs/?
} o[6y+ <'o
R@T6U:1
privatestaticint getCurrentPage(int currentPage){ J?:[$ C5
return currentPage == 0 ? 1 : currentPage; L$v^afP?
} `BZ&~vJ_
9vGs;
privatestaticint getBeginIndex(int everyPage, int K7vw3UwGN
H ;@!?I
currentPage){ nw'-`*'rj
return(currentPage - 1) * everyPage; u~ F;xQ
} ek-!b!iI
D>T],3U(H
privatestaticint getTotalPage(int everyPage, int nX%AeDBAT
P]<= ! F
totalRecords){ 9 |:^k.
int totalPage = 0; 2O""4_G
%I4zQiJ%
if(totalRecords % everyPage == 0) d}0qJoH4
totalPage = totalRecords / everyPage; W 5DbFSgB
else (
76{2
totalPage = totalRecords / everyPage + 1 ; Aa(<L$e!`
*crw^e
return totalPage; d;suACW
} ]YD(`42 x
M StX*Zw
privatestaticboolean hasPrePage(int currentPage){ M?6;|-HH
return currentPage == 1 ? false : true; X}JWf<=q
} D,W\ gP/h%
L=1~ f-
privatestaticboolean hasNextPage(int currentPage, c]m! G'L_/
.;Y
x*]
int totalPage){ j]> uZalr
return currentPage == totalPage || totalPage == #Q6w+"
fNhT;Bux
0 ? false : true; I"Q<n[g0'
} 03E3cp"
xUj2]Q>R+
DzDj)7
} ; h+ q
}$)&{d G
lCFU1 GHH
dK# h<q1
<?|6*2_=
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 R7aXR\ R
ep?:;98|t
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8W{~wg`
|zMqJ.qu
做法如下: NNX%Bq
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 swZpWC
UH40~LxIma
的信息,和一个结果集List: o>u!CL<
java代码: ?M"HXu
9t}xXk
SI_?~Pf3k
/*Created on 2005-6-13*/ v72,h
package com.adt.bo; (5(fd.m+_
|Y{PO&-?r
import java.util.List; +u#Sl)F
33M}>$ZH
import org.flyware.util.page.Page; 2?1}ZXr
@W)/\AZ3
/** RUc \u93n
* @author Joa PN9^[X
*/ ohTd'+Lm
publicclass Result { >nNl^ yqW
ylim/`u}6
private Page page; {kG;."S+K
!&0a<~Wi
private List content; 4(sttd_
#XL`S
/** %(NN*o9"q
* The default constructor LH.%\TMN$
*/ %%x0w^
public Result(){ '{W3j^m7
super(); L`pY27|
} b\M b*o
j #es2;
/** Nc"NObe
* The constructor using fields
I9Om#m
* T8mY#^sW_
* @param page :4] J2U\@
* @param content Wa{%0inZ
*/ W%H]Uyt
public Result(Page page, List content){
BUV/twU)
this.page = page; 6*V8k%H
this.content = content; >OTl2F}4 !
} .CvFE~
Bj+wayMi
/** ac3_L$X[
* @return Returns the content. ofl'G] /$+
*/ mMslWe
publicList getContent(){ Djyp3uUA/
return content; 0hb/`[Q
} M(NH9EE
e-jw^
/** 6VGo>b;
* @return Returns the page. c0SX]4}
G
*/ k5g@myb-
public Page getPage(){ z=[l.Af_
return page; WySNL#>a
} +!G4tA$g
Qz# 3p3N?
/** 2>ys2:z
* @param content -#daBx
?
* The content to set. vD_u[j]
*/ c'xUJhEL
public void setContent(List content){ # UjEY9"M
this.content = content; Q^vGj</u
} Pb3EnNqYbM
TdNsyr}JG
/** -S`TEX
* @param page U>bP}[&S
* The page to set. J&'>IA
*/ iY}QgB< M
publicvoid setPage(Page page){ h<GyplG
this.page = page; FF8WTuzB+
} ?{?Vy9'B
} QXsfp
_d/GdeLs
Ia=&.,xub
*m iONc
,zc"udpKF
2. 编写业务逻辑接口,并实现它(UserManager, y Y'gx|\
$ #TID=
UserManagerImpl) -6(h@F%E
java代码: 3&O% &
*X%?3"WH8
vM5k4%D
/*Created on 2005-7-15*/ /DK*yS
package com.adt.service; =;kRk.qzy
Rd`{qW
import net.sf.hibernate.HibernateException; WW)_Wh
e6Wl7&@6
import org.flyware.util.page.Page; ?SHc}iaU#
w2.qT+;v
import com.adt.bo.Result; IiG4ib>)W
pHq{S;R2G
/** GjG{qR
* @author Joa >ly&+3S
*/ J,CJPUf&
publicinterface UserManager { Y+|L3'H
n P0Ziu'{
public Result listUser(Page page)throws jI@bTS o
%Y#[%~|(
HibernateException; >^M!@=/?J
MBnK&GS
} .%-6&%1
J[I"/sdk-
oVKsic?
9\\@I
=;
f(EYx)gZ
java代码: m0dFA<5-
{s9y@c*15.
"~.8eKRQ
/*Created on 2005-7-15*/ g?k#wj1uH
package com.adt.service.impl; 6)tB{:h&~0
Enq6K1@%G
import java.util.List; wz*)L
(pP
dVY(V&p
import net.sf.hibernate.HibernateException; #n6FQ$l8m
f(w#LuW<
import org.flyware.util.page.Page; "<g?x`iz
import org.flyware.util.page.PageUtil; G}Qk!r
KT]J,b
import com.adt.bo.Result; mR!&.R?
import com.adt.dao.UserDAO; -Z[R S{#+T
import com.adt.exception.ObjectNotFoundException; ifgr<QlG
import com.adt.service.UserManager; mmpr]cT@'k
_Ex*%Qf.
/** ba1$kU
* @author Joa 'p|Iwtjn>
*/ RGx]DP$5G
publicclass UserManagerImpl implements UserManager { .f?qUg
aHVdClD2o
private UserDAO userDAO; m=("N
#NVF\
/** >yPFL'
* @param userDAO The userDAO to set. 8VAYIxRv
*/ h1G*y
publicvoid setUserDAO(UserDAO userDAO){ ]IbPWBX
this.userDAO = userDAO; `K@df<}%*,
} J;Z>fAE7
Jfixm=.6
/* (non-Javadoc) b0zxT9
* @see com.adt.service.UserManager#listUser +cE tm
>TQBRA;'
(org.flyware.util.page.Page) 3_jCsX
*/ vS24;:f
public Result listUser(Page page)throws nDoiG#N0
s&QBFyKtJ
HibernateException, ObjectNotFoundException { ]L%R[Z!3
int totalRecords = userDAO.getUserCount(); q|]0on~]
if(totalRecords == 0) +ia(%[
throw new ObjectNotFoundException aJa^~*N/Aa
;([tf;
("userNotExist"); Kt!IyIa;Ht
page = PageUtil.createPage(page, totalRecords); kUaGok?
List users = userDAO.getUserByPage(page); A 4W
returnnew Result(page, users); tci%=3,)
} EV?47\~
u8k{N
} s2kZZP8-
:(?hLH.W[
~&j`9jdOj
&8_#hne_
7)(`
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 cf[u%{
6Y
{i%xs#0h
询,接下来编写UserDAO的代码: ]Re~V{uh
3. UserDAO 和 UserDAOImpl: ap$tu3j
java代码: ]htZ!; 8J
=`\,2Nb
:!iPn%
/*Created on 2005-7-15*/ Dy{`">a
package com.adt.dao; z)Q^j>%
y!6:
import java.util.List; 8$<AxNR
MkNURy>n&
import org.flyware.util.page.Page; ,<P[CUD&&
%d[xr h
import net.sf.hibernate.HibernateException; ,I&0#+}n
EAd:`X,Y
/** =u3@ Dhw
* @author Joa IL6f~!
*/ R,5$ 0_]|+
publicinterface UserDAO extends BaseDAO { %`\_l
!|:q@|-
%@
publicList getUserByName(String name)throws SX=0f^
BQ}.+T\
HibernateException; &<P^Tvqq&
`w=H'"Zv
publicint getUserCount()throws HibernateException; `Ig2f$}
eeJt4DV8v
publicList getUserByPage(Page page)throws b;{"lJ:+Z
;7n*PBUJJ
HibernateException; |^k1hX2?W
G*~*2>~
} AB&wn>q
^RyTK|SQ
;1g-z]
.yfqS|(
'/Cz{<,
java代码: qddT9U|8~
Fx99"3`3
07"Oj9NlA
/*Created on 2005-7-15*/ %3+hz$E
package com.adt.dao.impl; !@Vp Bl
V1 #aDfiW
import java.util.List; ftU5A@(T
hG;=ci3EE
import org.flyware.util.page.Page; /^eemx
t{s*3k/
import net.sf.hibernate.HibernateException; VrE5^\k<a
import net.sf.hibernate.Query; .d!*<`S|
v_h*:c
import com.adt.dao.UserDAO; 9w<Bm"G
jsaCnm>&
/** UR2)e{RXg
* @author Joa Uu:v4a
*/ HgATH
public class UserDAOImpl extends BaseDAOHibernateImpl 5t#]lg[06'
N&h!14]{Z
implements UserDAO { Ib8{+j
RZh)0S>J
/* (non-Javadoc) ?[B[ F
* @see com.adt.dao.UserDAO#getUserByName O Lup`~
6:tr8 X_
(java.lang.String) Jv.R?1;8i
*/ ({nSs5)$
publicList getUserByName(String name)throws O:p649A
fToI,FA
HibernateException { U*:'/.
String querySentence = "FROM user in class SfL`JNi)
l'%R^
com.adt.po.User WHERE user.name=:name"; 3(*s|V"
Query query = getSession().createQuery ,4W((OQ^
",V5*1w
(querySentence); 5m?$\h
query.setParameter("name", name); }V;]c~Q/H
return query.list(); yZ0ZP
} *Y0,d`
r+pjv_R
/* (non-Javadoc) 2vQ^519
* @see com.adt.dao.UserDAO#getUserCount() Qb{5*>
*/ yP4.Z9
publicint getUserCount()throws HibernateException { I'b]s~u
int count = 0; jUSr t)o03
String querySentence = "SELECT count(*) FROM Z`c{LYP,y"
<XrGr5=BV
user in class com.adt.po.User"; \%Q
rN+WQ
Query query = getSession().createQuery rXPx*/C
#e>MNc
'z
(querySentence); dKpa5f7
count = ((Integer)query.iterate().next 't.F.t
a\_,_psK
()).intValue(); 1tz .e\
return count; >v,j;[(
} oz@6%3+
7!nAWlQ&-E
/* (non-Javadoc) Hvo27THLo
* @see com.adt.dao.UserDAO#getUserByPage XO~^*[K
++"PPbOe&D
(org.flyware.util.page.Page) K({,]<l5
*/ $Xc<K_Z
publicList getUserByPage(Page page)throws ITlkw~'G
j!7Uj]
HibernateException { ;}'<`(f&nX
String querySentence = "FROM user in class -V<"Ay
j)qh>y)
com.adt.po.User"; {U-EBXV
Query query = getSession().createQuery `_^=OOn
VW`=9T5%@
(querySentence); *G41%uz
query.setFirstResult(page.getBeginIndex()) ,`@|C
Z-4A
.setMaxResults(page.getEveryPage()); ~U+'3.Wo
return query.list(); 0|;=mYa4M
} rNyK*Wjt
MV\zwH
} U~t(YT
cpnwx1q@
]bweQw@i
c%.&F
nB0ol-<
至此,一个完整的分页程序完成。前台的只需要调用 'Sh5W%NM
We?:DM
[
userManager.listUser(page)即可得到一个Page对象和结果集对象 G3?z.5,Q
#sZes
的综合体,而传入的参数page对象则可以由前台传入,如果用 oyw1N;K
&[5az/Hj*
webwork,甚至可以直接在配置文件中指定。 ),,vu
5-^twXC&
下面给出一个webwork调用示例: +KNr1rG
java代码: c
@fc7
j]&{ @Y
G].KJ5,y
/*Created on 2005-6-17*/ 'VEpVo/
package com.adt.action.user; e*H$c?7NL
Din)5CxFX
import java.util.List; K^\9R
'DQyB`V2y
import org.apache.commons.logging.Log; pASVnXJZ
import org.apache.commons.logging.LogFactory; n\Ixv
import org.flyware.util.page.Page; S
&u94hlC
||aU>Wj4
import com.adt.bo.Result; >,3
3Jx
import com.adt.service.UserService; 9lV'3UG-?
import com.opensymphony.xwork.Action; 4PQWdPv;
7!%"8Rl-
/** Q@n k T1o
* @author Joa "g-NUl`'
*/ !&[4T#c
publicclass ListUser implementsAction{ N<99K!
Z]BRMx
privatestaticfinal Log logger = LogFactory.getLog gBu4`M
e.V){}{V
(ListUser.class); |e&Kg~~C
aK'r=NU
private UserService userService; 9MxGyGz$
hgGcUpJy?
private Page page; mGvP9E"&
vNGvEJ`qn
privateList users; ( Iew%U
W:\VFPf2
/* 7ow1=%Q
* (non-Javadoc) +E4_^
* 6! 'Xo:p
* @see com.opensymphony.xwork.Action#execute() fZ$2bI=
*/ E"=$p$k
publicString execute()throwsException{ _8
J(;7
Result result = userService.listUser(page); }q9f,mz
page = result.getPage(); <lR8MqjM_
users = result.getContent(); Hr$5B2'
return SUCCESS; I2'?~Lt
} $hio(
mz1g8M`@[D
/** o1\8>Ew
* @return Returns the page. &bQ^J%\
*/ 9"S3A EI
public Page getPage(){ Xl;N=fc
return page; UB}mI0/w
} u:ISwAp
{y'kwU
/** X!Q"p$D4(
* @return Returns the users. h 8s*FI
*/ 2dfA}i>k
publicList getUsers(){ h%%'{^>~
return users; D#0}/
} xXZN<<f59
X*KT=q^?n
/** |4vk@0L
* @param page }_ E
* The page to set. ]7;;uhn`
*/ ']Z8C)tK
publicvoid setPage(Page page){ G1rgp>m
this.page = page; dkjL;1
} Jp- hFD
}R^{<{KVJ
/** {`VQL 6(i
* @param users h.nz kp5
* The users to set. !?{5ET,gtN
*/ I8y\D,
publicvoid setUsers(List users){ \GWC5R7Q0j
this.users = users; +\4=G@P.J
} DcS~@ ;
Yh=Zn[U
/** \T0`GpE
* @param userService BeQJ/`
* The userService to set. eW/Hn
*/ Ax
^9J)C
publicvoid setUserService(UserService userService){ Eq
t61O$x
this.userService = userService; dSbV{*B;>
} -t]0DsPg
} i|*:gH
<3HJkcYGz
u|e2T@t=
Oaui@q
c!zu0\[Id
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, W8)GT`\
f&:g{K
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 qpZ".
fOfp.`n
么只需要: FwyPmtBj
java代码: ]l`DR4
=
|c)#zSv
ec|IT0;
<?xml version="1.0"?> {PZe!EQ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork N}\i!YUD
NJ.kT uk
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <T['J]k%
Ks4TBi&J
1.0.dtd"> m35G;
ZP1EO Z
<xwork> ws=y*7$y
@B+];lr/-
<package name="user" extends="webwork- rVLA"x 9u
E)Dik`Ccl
interceptors">
m{~r6@
YV+e];s
<!-- The default interceptor stack name B6BOy~B0
QFMS]
--> b+kb7
<default-interceptor-ref X:YxsZQ5Y
Z=#!FZ{
name="myDefaultWebStack"/> q;rU}hAzG0
^VA)vLj@
<action name="listUser" _Q QO&0Z
c8(.bmvF
class="com.adt.action.user.ListUser"> %BL +'&q
<param 4WLB,<b}
/SyiJCx0
name="page.everyPage">10</param> %lujme
<result @^%# ]x,:
_b+3;Dy
name="success">/user/user_list.jsp</result> Q,scjt[
</action> k
v b"n}
akR*|iK#b
</package> 1Z`zdZs
,\VNs'j
</xwork> 3 Tt8#B
k7j;'6
'{),gV.
Xs4`bbap
IlH*s/
.69{GM?
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 &`@K/Nf$9
U@H SU%H
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 E]bjI$j
>scEdeM
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ]1X];x&e
V4|pZ]
oC[$PPqX#
@hk~8y]rz
g1Aq;Ah /
我写的一个用于分页的类,用了泛型了,hoho ;:v:pg8qc
<MoWS9s!yb
java代码: |',Gy\Sj
B7cXbUAQs
WO|#`HM2
package com.intokr.util; a4c~ThbI
l/Sb JrM*
import java.util.List; Kpg]b"9.R
nP] ~8ViS
/** 'En 6h" {
* 用于分页的类<br> t'^/}=c-
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1D 6iJ
* Z O&5C6qa
* @version 0.01 =YR/|9(
* @author cheng 9\V^q9l
*/ }yUZ(k#
public class Paginator<E> { b*7OIN5h
privateint count = 0; // 总记录数 =^NR(:SaaU
privateint p = 1; // 页编号 M5wj79'l"
privateint num = 20; // 每页的记录数 O0e6I&u:
privateList<E> results = null; // 结果 SwLul4V
h&&ufF]D
/**
TwY]c<t
* 结果总数 4~D?F'o
*/ d&F8nBIM5
publicint getCount(){ ~i(X{^,3
return count; ~qs97'
} TC'tui
Q1g@FsW&U
publicvoid setCount(int count){ M*|x,K= U
this.count = count; Ue!
&Vm
}
'RXhE
9|fg\C
/** .^ soX}
* 本结果所在的页码,从1开始 =}F &jl
* sT| 8a
* @return Returns the pageNo. K%.\@l2Cp
*/ ]JbGP{UiN
publicint getP(){ 9%pq+?u9
return p; c5pF?kFaD
} &;|/I`+
Fc{hzqaP8
/** XB
zcbS+
* if(p<=0) p=1 .cjSgK1
* z.--"cF
* @param p Ov h[qm?Z
*/ \IIR2Xf,K
publicvoid setP(int p){ fQM:NI?9?
if(p <= 0) '`I&g8I\
p = 1; x8w455
this.p = p; CM_FF:<tn
} ;mu^WIj
^ 14U]<
/** o/
ozX4C
* 每页记录数量 ,!Gw40t
*/ abp]qvCV
publicint getNum(){ GG-7YJ
return num; Ru`&>E
} >:WnCkbp
ycTX\.KV
/** > X<pzD3u
* if(num<1) num=1 rLtB^?A z
*/ ,E<(K8
publicvoid setNum(int num){ R_`i=>Z-
if(num < 1) :2vk
vLM
num = 1; zuwlVn
this.num = num; F|Pf-.r`t
} akoK4!z
+iY .Y V
/** |wZcVct~
* 获得总页数 Kf/1;:^
*/ fYBmW')
publicint getPageNum(){ KEEHb2q
return(count - 1) / num + 1; &Ba` 3V\M
} f%<kcM2
Cz` !j
/** p3`ND;KQ
* 获得本页的开始编号,为 (p-1)*num+1 2r4owB?
*/ h\k@7wgu
publicint getStart(){ c 2t<WRG
return(p - 1) * num + 1; @9Rgg9r
} }rRf4te
@i U@JE`C
/** ?RNm8,M
* @return Returns the results.
&NM.}f
*/ DryN}EMOKD
publicList<E> getResults(){ p~Di\AQ/
return results; j51Wod<[
} >+Z BQ]~
FxeDjAP
public void setResults(List<E> results){ "^Y)&