Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 t@#5
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 UE5,Ml~X
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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 _~CJitR3
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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 (t&`m[>K
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分页支持类: , vvfk=-
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java代码: wDoCc:
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package com.javaeye.common.util; zb[kRo&a0W
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import java.util.List; LzLJ6A>;R
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publicclass PaginationSupport { _nzq(m1@
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publicfinalstaticint PAGESIZE = 30; Z)~?foe'
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privateint pageSize = PAGESIZE; K\ B!tk
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privateList items; paN=I=:*M
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privateint totalCount; X1}M_h%
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privateint[] indexes = newint[0]; T>1#SWQ/9
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privateint startIndex = 0; 3j$,L(
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public PaginationSupport(List items, int ,3}+t6O"
+&f_k@+
totalCount){ ,Iz9!i
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setPageSize(PAGESIZE); Yyd}>+|<,
setTotalCount(totalCount); !~F oy F
setItems(items); Cpd>xXZz&S
setStartIndex(0); '
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} +ru `Zw5,
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public PaginationSupport(List items, int am.d^'
;}S_ PnwC@
totalCount, int startIndex){ 4mp)v*z
setPageSize(PAGESIZE); +RpCh!KP
setTotalCount(totalCount); zCA8}](C^
setItems(items); 3K~^H1l
setStartIndex(startIndex); D1>*ml
} @|ZUyat
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public PaginationSupport(List items, int bL0]Yuh
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totalCount, int pageSize, int startIndex){ IN1n^f$:
setPageSize(pageSize); #2Q%sE?
setTotalCount(totalCount); rs>,p)
setItems(items); g]44|9x(W
setStartIndex(startIndex); BDPE.8s
} pcscNUp
hB\BFVUSn/
publicList getItems(){ j+AZ!$E
return items; W6EEC<$JL
} r/ATZAgHP
<)O#Y76s
publicvoid setItems(List items){ q\!"FDOl4
this.items = items; n@bkZ/G
} +J| LfXgB
W}D[9zo/
publicint getPageSize(){ VY~*QF~P
return pageSize; c; .y
} ]CS
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publicvoid setPageSize(int pageSize){ fWfhs}_
this.pageSize = pageSize; k8}'@w
} $`0^E#Nl
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publicint getTotalCount(){ u\xrC\Ka
return totalCount; G5 )"%G.
} "k [$euV
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publicvoid setTotalCount(int totalCount){ fIx|0,D&7L
if(totalCount > 0){ IWN18aaL?
this.totalCount = totalCount; S$wC{7?f
int count = totalCount / 'i3-mZ/|8
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pageSize; KU+u.J
if(totalCount % pageSize > 0) +dq2}gM
count++; R"t2=3K
indexes = newint[count]; +ZE"pA^C
for(int i = 0; i < count; i++){ y\iECdPU
indexes = pageSize * u5U^}<}y}
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i; F)'_,.?0
} Bgsi$2hI
}else{ !VG
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this.totalCount = 0; =.m/X>
} srImk6YD
} #z_.!E
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publicint[] getIndexes(){ \:n<&<aVSr
return indexes; ZS_
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} T|YMU?4
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publicvoid setIndexes(int[] indexes){ 98zJ?NaD&
this.indexes = indexes; UNrO$aX!1'
} 9K&YHg:1
)r*F.m{&:
publicint getStartIndex(){ |N^8zo :
return startIndex; ;uZq_^?:9&
} rO1N@kd/
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publicvoid setStartIndex(int startIndex){ gK *=T
if(totalCount <= 0) 5X]f}6kT
this.startIndex = 0; XL1x8IB
elseif(startIndex >= totalCount) VeFfkg4
this.startIndex = indexes V5jy,Qi)
b|k(:b-G&.
[indexes.length - 1]; a[!:`o1U
elseif(startIndex < 0) V2 ;?
this.startIndex = 0; pnv)D}"
else{ ESS1 L$y
this.startIndex = indexes +H?
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##]
`
[startIndex / pageSize]; KmD#Ia
} 9I1`* 0A
} j{ri]?p
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publicint getNextIndex(){ Fb{HiU9<!
int nextIndex = getStartIndex() + 1[RI
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pageSize; kk
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if(nextIndex >= totalCount) [-)BI|S:
return getStartIndex(); ?%Pi#%P
else vhU
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return nextIndex; Q? Xqf7y
} -3y
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publicint getPreviousIndex(){ $ O;a~/T
int previousIndex = getStartIndex() - j3
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3?&P^{
pageSize; %~Wr/TOt+
if(previousIndex < 0) !i{5mc\
return0; @GQtyl;q
else ICWHEot
return previousIndex; V-dub{K
} Djp;\.$(
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} RS{E|
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抽象业务类 ]e?L,1-
java代码: ?Bd6<F-G
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/** [&p/7
* Created on 2005-7-12 |[/XG2S
*/ EhOB+Mc1
package com.javaeye.common.business; ch/DBu
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import java.io.Serializable; - l0X]&Ex
import java.util.List; <Um 5w1
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import org.hibernate.Criteria; #<w2xR]:
import org.hibernate.HibernateException; 8/|1FI
import org.hibernate.Session; 7 z+Ngt' !
import org.hibernate.criterion.DetachedCriteria; +DSZ(Zb4qY
import org.hibernate.criterion.Projections; @`SlOKz!=
import xwijCFI*
3`njQvI\
org.springframework.orm.hibernate3.HibernateCallback; [5P1 pkZ
import o~'UWU'#
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org.springframework.orm.hibernate3.support.HibernateDaoS h7}P5z0F
;'4Kg@/
upport; }~ga86:n0
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import com.javaeye.common.util.PaginationSupport; AT"!Ys|
jXyK[q&O&
public abstract class AbstractManager extends @l~MY*hp
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HibernateDaoSupport { -
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privateboolean cacheQueries = false; iB{l:
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privateString queryCacheRegion; "Qe2U(Un
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publicvoid setCacheQueries(boolean 3=^B
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cacheQueries){ 0&6(y*
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this.cacheQueries = cacheQueries; ru*}lDJ
} 04!akPP<
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publicvoid setQueryCacheRegion(String J['?ud}@
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queryCacheRegion){ hJoh5DIE95
this.queryCacheRegion = 4~0@(3
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queryCacheRegion; $4>x4*
} EvDg{M}
k=.pcDX
publicvoid save(finalObject entity){ 6p~8(-nG
getHibernateTemplate().save(entity); jbu+>
} :h<QM$P<
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publicvoid persist(finalObject entity){ 7p Zd?-6M^
getHibernateTemplate().save(entity); -+ Mh('K
} ;#dzw!+Y
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publicvoid update(finalObject entity){ ' n "n;
getHibernateTemplate().update(entity); \.MPjD
} >m`<AynJ
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publicvoid delete(finalObject entity){ $7&t`E)qY
getHibernateTemplate().delete(entity); WeS$$:ro
} P<R'S
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publicObject load(finalClass entity, @@+BPLl
)9V8&,
finalSerializable id){ #}nDX4jI
return getHibernateTemplate().load 8FT@TUFb
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(entity, id); bqm%@*fZo
} J]$]zD
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publicObject get(finalClass entity, ^$J.l+<hy
Ku] <$uo
finalSerializable id){ 95BRZ!ts
return getHibernateTemplate().get xayd_RB 9
s!j vBy
(entity, id); a^Lo;kHY
} [7=?I.\Cr7
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publicList findAll(finalClass entity){ N5@l[F7I
return getHibernateTemplate().find("from sFonc
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" + entity.getName()); (p}N
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} PQ4)kVT
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publicList findByNamedQuery(finalString Q`(h
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namedQuery){ FK`M+ j
return getHibernateTemplate +dF/$+t
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().findByNamedQuery(namedQuery); C_V5.6T!
} PRyzUG&
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publicList findByNamedQuery(finalString query, ?H(']3X5@
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finalObject parameter){ "A3V(~%!
return getHibernateTemplate |C.[eHe&D
"| KD$CY
().findByNamedQuery(query, parameter); DzG$\%G2R}
} \kVi&X=q:
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publicList findByNamedQuery(finalString query, 3v:c'R0
oh^QW`#(
finalObject[] parameters){ 1A;f[Rze
return getHibernateTemplate cR/z; *wr7
OE_A$8L
().findByNamedQuery(query, parameters); y>_*}>2 ,O
} $Rv(v%
.V\:)\<|
publicList find(finalString query){ Tq!.M1{&
return getHibernateTemplate().find s_Gf7uC
~ZZJ/Cu
(query); hYU4%"X
} Y|N.R(sAs&
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publicList find(finalString query, finalObject p& +w
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parameter){ nM6/c
return getHibernateTemplate().find ;\)N7SJ
) E(9
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(query, parameter); WeRX ~
} #tQ__V
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public PaginationSupport findPageByCriteria G}p*oz~
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(final DetachedCriteria detachedCriteria){ ?cD2EX%(
return findPageByCriteria >p@v'h/Cr
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); kESnlmy@J
} cr<ty"3\
! )PV-[2
public PaginationSupport findPageByCriteria AWn$od`#s
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(final DetachedCriteria detachedCriteria, finalint },(Ln%M
-mAi7[omh
startIndex){ N2Q%/}+,
return findPageByCriteria $g!~T!p=
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(detachedCriteria, PaginationSupport.PAGESIZE, i4^1bd
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startIndex); a C<
} <c$K3
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public PaginationSupport findPageByCriteria UfAN)SE"
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(final DetachedCriteria detachedCriteria, finalint ?PST.+l
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pageSize, h!h<!xaclW
finalint startIndex){ :~{x'`czJ
return(PaginationSupport) v'H\KR-;
55]E<2't
getHibernateTemplate().execute(new HibernateCallback(){ %_%/ym
publicObject doInHibernate a.!|A(zw
Y; OqdO
(Session session)throws HibernateException { P{_Xg,Z
Criteria criteria = BARs1^pR4
leomm+f^
detachedCriteria.getExecutableCriteria(session); ~k[q:$T
int totalCount = Ec;{N
ZVX!=3VT
((Integer) criteria.setProjection(Projections.rowCount 5zR9N>!c
f+iM_MI
()).uniqueResult()).intValue(); Vv3{jn6%
criteria.setProjection + U];
9 9S-P}xd
(null); `U[s d*C"
List items = ?ta(`+"
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criteria.setFirstResult(startIndex).setMaxResults ( 17=|s
{#X]D~;s+
(pageSize).list(); 8O0E;6b
PaginationSupport ps = -^+!:0';
NT}r6V(Aju
new PaginationSupport(items, totalCount, pageSize, [$[1|r
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startIndex); 3iC$ "9!p
return ps; I? o)X!
} (#`1[n+b`x
}, true); v?en-,{A
} r^,XpRe&M
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public List findAllByCriteria(final +IpC
+{F2hEYP
DetachedCriteria detachedCriteria){ 3
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return(List) getHibernateTemplate mzkv/
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().execute(new HibernateCallback(){ <>tQa5;
publicObject doInHibernate NiCB.a
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(Session session)throws HibernateException { ~gAp`Q
Criteria criteria = q!+&|F
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detachedCriteria.getExecutableCriteria(session); <5wk~|@t
return criteria.list();
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} =Pu;wx9
}, true); 9;*-y$@
} &>]c"?C*
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public int getCountByCriteria(final FhkS"y
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DetachedCriteria detachedCriteria){ ,m)k;co^
Integer count = (Integer) [hl8LP+~
sKK*{+,kh;
getHibernateTemplate().execute(new HibernateCallback(){ =T0;F0@#4
publicObject doInHibernate R&`; C<6}D
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(Session session)throws HibernateException { 6~@S,i1
Criteria criteria = _'"whZ)2
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detachedCriteria.getExecutableCriteria(session); /\0rRT
return ,fa'
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criteria.setProjection(Projections.rowCount }KZt7)
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()).uniqueResult(); ^[]@dk9
} c4'k-\JvT
}, true); f1_b``M
return count.intValue(); #OT8_D
} {r,MRZaa
} !lk
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用户在web层构造查询条件detachedCriteria,和可选的 C=&rPUX{
UHh7x%$n
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ipThwp9
BS_ 3|
PaginationSupport的实例ps。 AJ0
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ps.getItems()得到已分页好的结果集 ]?#E5(V@x
ps.getIndexes()得到分页索引的数组 % >\v6ea
ps.getTotalCount()得到总结果数 >&z=ktB
ps.getStartIndex()当前分页索引 sG6ts,={
ps.getNextIndex()下一页索引 t(RJc
ps.getPreviousIndex()上一页索引 \69h>h
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 'wg>=|Q5
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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 FZ0wtS2
ruKm_j#J
一下代码重构了。 +=:*[JEK,U
pp2,d`01[L
我把原本我的做法也提供出来供大家讨论吧: RiPxz=kr
Sl!#!FGI
首先,为了实现分页查询,我封装了一个Page类: /YLHg5n8+
java代码: R|&Rq(ow"
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/*Created on 2005-4-14*/ o;zU;pkB
package org.flyware.util.page; @|jLw($Ly
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/** a
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* @author Joa )#H&lH
* L^{1dVGWNa
*/ e@ mjh,
publicclass Page { *:+&SxL
X^td`}F/=V
/** imply if the page has previous page */ djk?;^8
privateboolean hasPrePage; Jx jP'8
T{"[Ih3Mbl
/** imply if the page has next page */ KqD]GS#(
privateboolean hasNextPage; Oe/&Ryj=mm
g"dq;H
/** the number of every page */ <*/IV<
privateint everyPage; %wDE+&M
EDA%qNd]j
/** the total page number */ 5p}ri,Y<
privateint totalPage; zJ=lNb?q
NR6wNz&81
/** the number of current page */ +&*D7A>~p
privateint currentPage; VbG#)>"F
S <RbC
/** the begin index of the records by the current n?[JPG2X
Mxmo}tt
query */ ev'` K=n8
privateint beginIndex; V 4`
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/** The default constructor */ x* 9 Xu"?
public Page(){ J\@W+/#dF
^vHh*Ub
} MP3Vo|}3
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/** construct the page by everyPage )/y7Fh
* @param everyPage $0mR_pA\fW
* */ .DX-biX,
public Page(int everyPage){ x@)G@'vV|
this.everyPage = everyPage; JH|]B|3
} s;ivoGe}
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/** The whole constructor */ _ g8CvH)?!
public Page(boolean hasPrePage, boolean hasNextPage, E-`3}"{
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vmj'X>Q
int everyPage, int totalPage, li37*
int currentPage, int beginIndex){ [pRRBMho
this.hasPrePage = hasPrePage; 1`Ig A0V`"
this.hasNextPage = hasNextPage; Ct<]('Hm(
this.everyPage = everyPage; KL<,avC/
this.totalPage = totalPage; Ym8
V)
this.currentPage = currentPage; D^Gs_z$['
this.beginIndex = beginIndex;
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} :u9OD` D
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/** gJZH??b
* @return LsI8T
uv
* Returns the beginIndex. $ o
}
*/ MtD0e@
publicint getBeginIndex(){ Mp7X+o/
return beginIndex; }`~n$OVx
} _yRD*2 !;
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/** DP8%/CV!*
* @param beginIndex 6KRC_-
* The beginIndex to set.
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*/ WqJrDj~
publicvoid setBeginIndex(int beginIndex){ jl"su:y
this.beginIndex = beginIndex; ! }>CEE
}
I !J'
jf^BEz5
/** EvKzpxCh
* @return X=KC+1e
* Returns the currentPage. OfK>-8
*/ idNra#
publicint getCurrentPage(){ Rz#q68
return currentPage; k.ttrKy<q/
} Q@
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/** srQGqE~
* @param currentPage %xv*#.<Vj
* The currentPage to set. eev-";c
*/ B2,c_[UZ.
publicvoid setCurrentPage(int currentPage){ q|g>;_
this.currentPage = currentPage; 8CUlE-R5
} 3oOr*N3R
6E#znRi6IE
/** dSI<s^n
* @return we/sv9v}n
* Returns the everyPage. cSTF$62E
*/ RG.wu6Av
publicint getEveryPage(){ v{X<6^g
return everyPage; .%EYof
} NZ"nG<;5
r])V6 ^U
/** 82M`sk3.
* @param everyPage U0;pl2
* The everyPage to set. VTa%
*/ cN-$;Ent
publicvoid setEveryPage(int everyPage){ jVPX]8
this.everyPage = everyPage; SJ2l6
} al" =ld(
f~10 iD
/** [jv+Of
IZ
* @return kMx)G]
* Returns the hasNextPage. }/lyrjV
*/ tv_&PIu]L
publicboolean getHasNextPage(){ @'9m()%-]g
return hasNextPage; ?C`r3
} *XOLuPL>6)
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/** 8'"=y}]H~
* @param hasNextPage tZG l^mA"g
* The hasNextPage to set. N%F4ug@i
*/ P1R5}i
publicvoid setHasNextPage(boolean hasNextPage){ 2){O&8 A
this.hasNextPage = hasNextPage; PJYUD5
} wF9L<<&B
O6ph_$nt.
/** [MuZ^'dR
* @return ?t5<S]'r$
* Returns the hasPrePage.
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*/ /i~x.i3
publicboolean getHasPrePage(){ zI0d
return hasPrePage; }xry
} NBL%5!'
H:)_;k
/** @^Rl{p
* @param hasPrePage UM/!dt}DnF
* The hasPrePage to set. y 2)W"PuG
*/ 6e8 gFQ"w2
publicvoid setHasPrePage(boolean hasPrePage){ .DI?-=p|_#
this.hasPrePage = hasPrePage; osl\j]U8
} 2qot(Zs1i
,+5:}hR+
/** d'"|Qg_'
* @return Returns the totalPage. wX5q=I
* $A`m8?bY
*/ dVUe!S`
publicint getTotalPage(){ W4,'?o
return totalPage; ('{aOiSH
} _, E/HAX
Cs(sar:7
/** >(-A"jf
* @param totalPage ?;y-skh
* The totalPage to set. >C19Kie72
*/ ]}kw'&
publicvoid setTotalPage(int totalPage){ ap8q`a{j^
this.totalPage = totalPage; 4l7
Ny\J
} K iEmvC
d@p#{ -
} ZS%W/.?
;{aGEOP'U
`U=Jbdc l3
Af\
Vm[F~2+HX
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 *NG\3%}%|@
b50mMWtG
个PageUtil,负责对Page对象进行构造: OIJT~Z}
java代码: zO---}[9a
h5rR44
BN `2UVH
/*Created on 2005-4-14*/ :G6aO
package org.flyware.util.page; 1yZA_x15:
L$i:~6
import org.apache.commons.logging.Log; *:Rs\QH
import org.apache.commons.logging.LogFactory; [}M!ez
q-+:1E
/** $4^SWT.
* @author Joa %ioVNbrR7
* S@Rd>4
*/ 0QT:@v2R
publicclass PageUtil { Fuzb4Df
ALy7D*Z]w
privatestaticfinal Log logger = LogFactory.getLog /`l;u7RD
}W'4(V;:
(PageUtil.class); ,<* I5:
n0!2-Q5U)h
/** f@$W5*j
* Use the origin page to create a new page +ZwoA_k{
* @param page !:m.-TE
* @param totalRecords 2Kf/I d1
* @return ^;'8yE/
*/ &y}7AV
publicstatic Page createPage(Page page, int ,:e~aG,B
@ ?M\[qeF@
totalRecords){ Q#G xo
return createPage(page.getEveryPage(), i6KB\W2
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page.getCurrentPage(), totalRecords); @,n)1*{P
} I8YUq
&
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/** *g,ls(r\[
* the basic page utils not including exception +8C}%6aX
Z[OX{_2]K
handler n."n?C'{
* @param everyPage L2,2Sn*4i
* @param currentPage rHTZM,zM=H
* @param totalRecords !8[T*'LJ-
* @return page 4`,7tj
*/ `hZh}K^
publicstatic Page createPage(int everyPage, int 9xO@_pkX
K^U="
currentPage, int totalRecords){ A1INaL
everyPage = getEveryPage(everyPage); = V2Rq(jH
currentPage = getCurrentPage(currentPage); O-X(8<~H=
int beginIndex = getBeginIndex(everyPage, Xg96I:r'p
:Y\ ~[Y
currentPage); 0M"n
int totalPage = getTotalPage(everyPage, W`_JERo
1,%`vlYv
totalRecords); F5qA!jZ1]
boolean hasNextPage = hasNextPage(currentPage, \1jThJn
yAryw{(
totalPage); H oABo:
boolean hasPrePage = hasPrePage(currentPage); ?UAuUFueA
dI
,A;.
returnnew Page(hasPrePage, hasNextPage, @k&6\1/U
everyPage, totalPage, Vf&U`K
currentPage, D9[19,2r`
1oej<67PdJ
beginIndex); I09 W=
} O{_t*sO9q*
vt{[_L(h
privatestaticint getEveryPage(int everyPage){ 8Y.qP"s
return everyPage == 0 ? 10 : everyPage; v*?8 :>:}
} JFVx&
6[3Xe_
privatestaticint getCurrentPage(int currentPage){ /iFn=pk1?
return currentPage == 0 ? 1 : currentPage; ANFes*8j
} IQ@9S
S>0%jCjW
privatestaticint getBeginIndex(int everyPage, int `P;r[j"
Q?i_Nl/|
currentPage){ Qdq;C,}Ai.
return(currentPage - 1) * everyPage; !iKW1ks
} ID2->J
~tA ^[tK
privatestaticint getTotalPage(int everyPage, int FC] *^B
%-blx)Pc
totalRecords){ N:)x67,
int totalPage = 0; Y2x|6{ #
Gu*y7I8
if(totalRecords % everyPage == 0) 2L~Vr4eHG
totalPage = totalRecords / everyPage; {6v.(Zlh$
else xrPZy*Y,
totalPage = totalRecords / everyPage + 1 ; e'.BTt58Y
-/pz3n
return totalPage; pPBXUu'
} |CDM(g>%
V|MHDMD=
privatestaticboolean hasPrePage(int currentPage){
p>7qyZ8
return currentPage == 1 ? false : true; X$>F78e*
} \R<MQ#
x
#{}?=/nJ~-
privatestaticboolean hasNextPage(int currentPage, (<eLj Q
N l@G\_
int totalPage){ ;_I>`h"r
return currentPage == totalPage || totalPage == ]&%KU)i?
{Nl?
0 ? false : true; [t?tLUg|6
} "Xv} l@
S&`6pN
6kH6"
} jg710.v:
ayA;6Qt
w0_P9g:
V1]GOmXz
r >'tE7W9
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。 Zo<)r2|O.
<a"(B*bBd
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 U3{<+vSR`
Z<i}XCE
做法如下: v0\l~_|H
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 l<+[l$0#
]eKuR"ob0
的信息,和一个结果集List: CM_hN>%w[
java代码: 4=^_VDlpd
]o<]A[<
Kz"3ba}KH
/*Created on 2005-6-13*/ idYB.]Y(
package com.adt.bo; ?:\/-y)Sp
,ErfTg&^
import java.util.List; zWEPwOlI1P
nqo{]fn
import org.flyware.util.page.Page; -Q n-w3~&
^v;)6a2
/** ( V4Ppg
* @author Joa dipfsH]p
*/ %]4Tff
publicclass Result { ,m=G9QcN
EB[T 5{
private Page page; N(7 XILC
Z\nDR|3
private List content; pN[WYM?[
vha9,5_
/** xsH1)
* The default constructor M@cFcykK
*/ 1C<cwd;9
public Result(){ CeYhn\m5K0
super(); 4-yK!LR
} CVfV
x(Bt[=,K3
/** ZM.'W}J{*
* The constructor using fields Z=]SAK`
* zKd@Ab
* @param page sUG!dwqqd
* @param content 3(WijtH
*/ +HS]kF H
public Result(Page page, List content){ FgH7YkKrD
this.page = page; {XOl &
this.content = content; i1B!oZ3q
} t1?aw<
Z mJ<h&
/** n~ *|JJ*`
* @return Returns the content. 7 9tE
*/ ?8-Am[xH
publicList getContent(){ ;M3%t=KV
return content; ]>X_E%`G<b
} _9h$8(wjn
.TGw+E1k
/** (DiduSJ
* @return Returns the page. ?@'&<o0p#
*/ aD: #AmbJ
public Page getPage(){ >&(#p@#
return page; )pHtsd. eP
} 1{a%V$S[
4qid+ [B
/** Wlc&QOfF
* @param content <w9~T TS
* The content to set. cXb*d|-|N
*/ 36=aahXd\
public void setContent(List content){ +u$l]~St\
this.content = content; #LasTN9
} ]}v]j`9m%
@ZJL]TO
/** ?4b0\ -
* @param page -Uo11'{
* The page to set. FP=B/!g
*/ ,#)d
publicvoid setPage(Page page){ Lk(ESV;r
this.page = page; 8c9HJ9vk
} ~+Gh{,f
} oqJYbim
EOB8|:*
b >D
uVEJV |^/
%B$ftsYXmu
2. 编写业务逻辑接口,并实现它(UserManager, RIMSXue*Ha
I8bM-k):9R
UserManagerImpl) XFS~
java代码: (tg.]q_=u
l)NkTZ<]
+M-tYE
5n
/*Created on 2005-7-15*/ `\UY5n72
package com.adt.service; &e^;;<*w
=%W:N|k
import net.sf.hibernate.HibernateException; &aRL}#U
0ID9=:J
import org.flyware.util.page.Page; Z*k(Q5&U
'I$FOH
import com.adt.bo.Result; J0!V (
1B;2 ~2X
/** p>tkRA?lk
* @author Joa A*OqUq/H`;
*/ .iy4
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publicinterface UserManager { H,(vTthd
#~
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public Result listUser(Page page)throws `p()ko
c1Ks{%iA
HibernateException; Q!+AiSTU
/yI4;:/
} A6]:BuP;c
EZ<:>V-_D
P73GH
qX@e+&4P0
/PwiZA3sA
java代码: %/A>'p,~
KfiSQ!{
O(-p
md,
/*Created on 2005-7-15*/ le/j!
package com.adt.service.impl; ve
d]X!
Q a (Sb
import java.util.List; JQ%hh&M\0
cACIy yQ
import net.sf.hibernate.HibernateException; KL_/f
!yd B,S
import org.flyware.util.page.Page; R #wZW&N
import org.flyware.util.page.PageUtil; ,j_js8r
lx|Aw@C3~
import com.adt.bo.Result; R%jOgZG
import com.adt.dao.UserDAO; z x-[@G
import com.adt.exception.ObjectNotFoundException; j}u L
import com.adt.service.UserManager; I-R7+o
-qP)L;n
/** 0"R>:f}
* @author Joa DsMo_m/"1
*/ JR]2Ray
publicclass UserManagerImpl implements UserManager { aF
2vgE\
/WnCAdDgZ
private UserDAO userDAO; F*KQhH7Gf
FSM M
/** 7fR5V
* @param userDAO The userDAO to set. HA0!>_I dC
*/ :Qge1/
publicvoid setUserDAO(UserDAO userDAO){ FOG{dio
this.userDAO = userDAO; x$d[Ovw-
} \foThLx
bN_e~ z
/* (non-Javadoc) )k(K/m
* @see com.adt.service.UserManager#listUser X~r9yl>
LA Crg
(org.flyware.util.page.Page) )-4c@
*/ Xe_ <]|
public Result listUser(Page page)throws D)PX |xrn
E*YmHJ:k
HibernateException, ObjectNotFoundException { )E.AY
int totalRecords = userDAO.getUserCount(); }+!"mJx@
if(totalRecords == 0) in1rDN%Vi
throw new ObjectNotFoundException D)-LZbPa
HgY@M
("userNotExist"); "&={E{pQ
page = PageUtil.createPage(page, totalRecords); 4;YP\{u
List users = userDAO.getUserByPage(page); QGpj$ _b
returnnew Result(page, users); N?qETp -:
} 2_wpj;E
*HD(\;i-$
} M`&t=0D
ZN}`A7
Z,)H f
+v
B}E
2'fd4rE5
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 |XB<vj07G
ql@2<V{
询,接下来编写UserDAO的代码: d#T5=5#
3. UserDAO 和 UserDAOImpl: J,W$\V]p
java代码: $+WXM$N
^&<M""Z
s&E,$|80
/*Created on 2005-7-15*/ }uIQ@f`
package com.adt.dao; ?2"g*Bak
jemb/:E
import java.util.List; 5ngs1ZF@
.eN"s'
import org.flyware.util.page.Page; #mU\8M,
AW r2Bv
import net.sf.hibernate.HibernateException; |5vJ:'` I
hrKeOwKHU
/** 8]#FvgX
* @author Joa }n&nuaj
*/ "bej#'M#
publicinterface UserDAO extends BaseDAO { +<\LY(o
8[@,i|kgg0
publicList getUserByName(String name)throws +'m9b7+v
11l=zv
HibernateException; ->I.D?p
FsqH:I4O
publicint getUserCount()throws HibernateException; 5X^\AW
oZ2:%
publicList getUserByPage(Page page)throws NV./p`k
(A?>U_@
HibernateException; YW7w>}aW
%f;v$rsZ
} HB )+.e
"[
S[vkI
x;W!sO@$
qXtC7uNj$
CNRSc4Le
java代码: XgxO:"B
W<q<}RSn
%i?
/*Created on 2005-7-15*/ Py*WHHO
package com.adt.dao.impl; ,It0brF
j*QdD\)
import java.util.List; ZW;Ec+n_K
Qy9_tvq
X
import org.flyware.util.page.Page; :0@0muo
_EMXx4J
import net.sf.hibernate.HibernateException; 4]1/{</B|
import net.sf.hibernate.Query; 6?,qysm06
xtGit}
import com.adt.dao.UserDAO; J;>;K6pW
q!W,2xqZoq
/** gbMA-r:IC
* @author Joa Vn_&q6Pa
*/ ?J$k
5;
public class UserDAOImpl extends BaseDAOHibernateImpl #_ulmB;
Ho(MO!(
implements UserDAO { \L>XF'o
#eYYu2ND
/* (non-Javadoc) (g;O,`|c,
* @see com.adt.dao.UserDAO#getUserByName -|'@:cIZ
-Jd7
(java.lang.String) Z+V%~C1
*/ W)1nc"WqY
publicList getUserByName(String name)throws H^Pq[3NQ
OX.5olb
HibernateException { kVLZdXn,q2
String querySentence = "FROM user in class | K|AUI
y3j$?oM
com.adt.po.User WHERE user.name=:name"; Jm ,:6T
Query query = getSession().createQuery FTUfJIVN(
t!wbT79/
(querySentence); pOK=o$1V8
query.setParameter("name", name); ;ZB=@@l(
return query.list(); "6]oi*_8
} {#+K+!SvDX
G9xl-ag+z
/* (non-Javadoc) MY{Kq;FvRP
* @see com.adt.dao.UserDAO#getUserCount() "`K_5"F
*/ JRBz/ j
publicint getUserCount()throws HibernateException { +_ehzo97
int count = 0; 12i`82>;
String querySentence = "SELECT count(*) FROM k|x mZA*
Dz hLb8k
user in class com.adt.po.User"; T}\>8EEG
Query query = getSession().createQuery !=30s;-
~98q1HgS]D
(querySentence); #U0| j?!D
count = ((Integer)query.iterate().next BUZ74
[e,xC!2
()).intValue(); YQ+8lANC
return count; X%-"b`
} jA8Bmwt;w
H`<u2fo|p
/* (non-Javadoc) 1<h@^s ;
* @see com.adt.dao.UserDAO#getUserByPage ~~Cd9Hzi
+Q"s!\5
(org.flyware.util.page.Page) fV9+FOZn
*/ 2KXFXR
publicList getUserByPage(Page page)throws &2:WezDF
!rgXB(
HibernateException { gD%o0jt"
String querySentence = "FROM user in class .z
CkB86
^Zs^
com.adt.po.User"; =l2 @'Y Q
Query query = getSession().createQuery dw#pObH|`
HziQ%QR
(querySentence); YeJTB}
query.setFirstResult(page.getBeginIndex()) `!N.1RP _
.setMaxResults(page.getEveryPage()); Wv5=$y
return query.list(); Y<^Or
} Up-^km
yo5-x"ze
} /p;OZf]
4Tuh]5
k'.cl^6Z8
bPV}T`
e8SAjl"}
至此,一个完整的分页程序完成。前台的只需要调用 tZ) ,Z<
DFfh!KKR$
userManager.listUser(page)即可得到一个Page对象和结果集对象 x15&U\U
%eF=;q
的综合体,而传入的参数page对象则可以由前台传入,如果用 c&#Q`m
GwgY{-|`
webwork,甚至可以直接在配置文件中指定。 /hg^hF
0XE6Hw
下面给出一个webwork调用示例: JWu0VLo
java代码: ixy:S1pI
o7tlkSZ
@0:Eg 1-
/*Created on 2005-6-17*/ C^JtJv
package com.adt.action.user; /"!ck2d&1
WO69Wo\C
import java.util.List; fZs}u<3Q)
!j6CvclT
import org.apache.commons.logging.Log; FBi&MZ`
import org.apache.commons.logging.LogFactory; 4J9Y
import org.flyware.util.page.Page; >]Mhkf/=)
9R+ qw
import com.adt.bo.Result; varaBFD
import com.adt.service.UserService; ,o2x,I
import com.opensymphony.xwork.Action; G"J
8i|~
<YG 42,N
/** 6 X2w)cO
* @author Joa SP=8v0
*/ 5[6{o$I
publicclass ListUser implementsAction{ 4M$"0}O;[h
Hm 0;[i
privatestaticfinal Log logger = LogFactory.getLog K_j*9@
L.9@rwfI
(ListUser.class); (=%0x"'
s7`2ky()kz
private UserService userService; Nc EPPl0I
zcV~)go6
private Page page; 7Or?$
GOCe&?
privateList users; k:U%#rb;
pcQzvLk
/* ;Uypv|xX
* (non-Javadoc) fsKZ
* ;x)f;!e+
* @see com.opensymphony.xwork.Action#execute() 9D5v0Qi
*/ +s+E!= s
publicString execute()throwsException{ d<_IC7$u>
Result result = userService.listUser(page); %Q93n {?
page = result.getPage(); ,=u!hg
users = result.getContent(); 93)1
return SUCCESS; VyIM ,glu
} /z1-4:^`A[
:y~l?0b&8
/** nqYarHi
* @return Returns the page. jTsQsHq
*/ Urm(A9|N
public Page getPage(){ FYaBP;@J%
return page; KjV1->r#
} '8^>Z.~V
,PWMl[X
/** CrGDo9JdvT
* @return Returns the users. *%]&5
*/ EzU=q
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publicList getUsers(){ x50ZwV&j
return users; @oRo6Y<-
} ,Igd<A=
z}$!B.)
/** 4n\O6$&.x
* @param page
?D@WXE0a
* The page to set. cS|W&IH1
*/ %&$s0=+
publicvoid setPage(Page page){ eeUEqM$7EX
this.page = page; :N=S nyz
} "V4ru&a
y $>U[^G[
/** 5F5)Bh
* @param users 8 }OII\
* The users to set. [@/x
*/ =eeZtj.
publicvoid setUsers(List users){ 4^w`]m
this.users = users; QL@}hw.F
} T;Ra/H
enQev?8%
/** ?Hf8<C} 3
* @param userService @3Mp>u/
* The userService to set. \BdQ(rm
*/ /s`8=+\9
publicvoid setUserService(UserService userService){ ~hQTxLp
this.userService = userService; Q[% +y.
} ^' b[#DG>F
} =@ed{~
$@ZrGT
3B ;aoejHm
sTzt
";/,FUJJ
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, k
3oR:
;LFs.Jc<
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 &_<!zJ;Hn
k%sh;1.
么只需要: uRRp8hht
java代码: #7,;/rtO7
8CGjI?j
F@@6D0\X?
<?xml version="1.0"?> IaYy5Rw
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 2u^/yl
/-C6I:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /: }"Z b
FP h1 }qS
1.0.dtd"> wb (quu
kiR+ Dsl
<xwork> aL0,=g%
`BKV/Xl
<package name="user" extends="webwork- p>0n~e
y(Ck j"
interceptors"> $r/tVu2!W
+J(@.
<!-- The default interceptor stack name t8z=R6zX
(Q][d+} /
--> 6nHyd<o
<default-interceptor-ref *gL-v]V
`RLn)a
name="myDefaultWebStack"/> Ab)X/g-I@
Hyz:i)2
<action name="listUser" + Awo\;@,
U=\!`_f':
class="com.adt.action.user.ListUser"> kmF@u@5M
<param (GDW9:
YhFd0A?]
name="page.everyPage">10</param> 0%GQXiy
<result LHgEb9\Q
nv2p&-e+
name="success">/user/user_list.jsp</result> Y.v. EZ
</action> D eM/B5qw
%Ig3udcY?
</package> IO]%AL(.;
+OX:T) 4h6
</xwork> z !:%Hbh=
m?pm)w
<aGfQg|554
rIZ^ix-N
dhmZ3 ~cW>
-jQMh
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 72{Ce7J4
V/,F6
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 N3QDPQ
f"g-Hbl5
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 t7qY!S (
|$a!Zx94^
UU"'
d{G*1l(X
1;N5@0%p
我写的一个用于分页的类,用了泛型了,hoho E [b6k&A
1|/]bffg!c
java代码: iF'qaqHWY4
tw%z!u[a
tg'2v/
package com.intokr.util; S{F'k;x/5
uQ'Izdm
import java.util.List; )xj!7:n)
]pP:
/** )r.4`5Rc
* 用于分页的类<br> QO(P_az3mg
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5Cjh%rj(jl
* >7I"_#x1:
* @version 0.01 k86j&
.m_
* @author cheng 55#s/`gd)^
*/ y?@(%PTp
public class Paginator<E> { ?0k4l8R
privateint count = 0; // 总记录数 brt1Kvu8(
privateint p = 1; // 页编号 TuX9:Q
privateint num = 20; // 每页的记录数 BEnIyVU;L
privateList<E> results = null; // 结果 k9vzxZ%s:
bAZx*qE=
/** Cqc5jx0)
* 结果总数 0mD=Rjb*a
*/ N=@Nn)
publicint getCount(){ 97SOa.@
return count; q}0xQjpo
} Q/<