Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 0t7yK
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 s@o"V >t
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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 Y_PCL9G{p
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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 wr*A%:
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。 r3Z-mJ$:
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分页支持类: [.z1
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java代码: ZH:#~Zyj
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package com.javaeye.common.util; TQ@*eoJj
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import java.util.List; ]2zx}D4f
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publicclass PaginationSupport { *JO"8iLw
;
@Gm@d
publicfinalstaticint PAGESIZE = 30; jy@}$g{
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privateint pageSize = PAGESIZE; o?{VGJH<v
m!;mEBL{
privateList items; Y<#7E;aL
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privateint totalCount; V^L;Nw5h
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privateint[] indexes = newint[0]; m/Yi;>I(
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privateint startIndex = 0; !h9 An
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public PaginationSupport(List items, int C
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totalCount){ ,b{G(sF
setPageSize(PAGESIZE); 8n~@Rj5
setTotalCount(totalCount); , is
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setItems(items); 5Y9 j/wA
setStartIndex(0); `m'2RNSc+#
} *QLl
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public PaginationSupport(List items, int M;Vx[s,#,
2~]c`/M3
totalCount, int startIndex){ G2L7_?/m
setPageSize(PAGESIZE); ^Gs!" Y
setTotalCount(totalCount); +}9%Duim
setItems(items); uF(-h~
setStartIndex(startIndex); OgfQGGc
} \D}/tz5~B
u4+VG5.rhT
public PaginationSupport(List items, int `hH1rw@7<
tO~H/0
totalCount, int pageSize, int startIndex){ $ h_ @`j
setPageSize(pageSize); |y'q`cY
setTotalCount(totalCount); aUA+%
setItems(items); Q_uv.\*z_
setStartIndex(startIndex); C t SAo\F
} ?on3z
o)-Qd3d%S
publicList getItems(){ iwmXgsRa9}
return items; TD3R/NP
} UJ6WrO5#kB
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publicvoid setItems(List items){ [|F.*06SK
this.items = items; *4(.=k
} , H[o.r=
cIgFSwQ4
publicint getPageSize(){
,:z@Ji
return pageSize; :wn{ Vx#xq#wK
this.pageSize = pageSize; Pel3e ~?t
} %|,j'V$
o^AK@\e:^Z
publicint getTotalCount(){ ;2X1 qw>
return totalCount; zR`]8E]
} +w}5-8mH&>
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publicvoid setTotalCount(int totalCount){ DsFrA]
if(totalCount > 0){ @7BH`b$)!
this.totalCount = totalCount; bTn-Pg){
int count = totalCount / g\jdR_/
8} S|iM
pageSize; 7v\OS-
if(totalCount % pageSize > 0) #D}NT*w/
count++; 9h9Y:i*Gh5
indexes = newint[count]; Y*7.3 +#
for(int i = 0; i < count; i++){ kU#$
indexes = pageSize * WRo#ZVt9$
[(dAv7YbN
i; 5B@&]-'~
} l[h??C`
}else{ 9vVYZ}HC
this.totalCount = 0; 5qFqH
} t(s']r
} q|Ga
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publicint[] getIndexes(){ ,>e<mphM
return indexes; E7 7Au;TL
} t/y0gr tm6
3 i>uKU1
publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; 1s1$J2LX
} "S6d^
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publicint getStartIndex(){ )C <sj
return startIndex; %)]{*#N4
} 1tfm\/V}ho
AC
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publicvoid setStartIndex(int startIndex){ %"{SGp
if(totalCount <= 0) /pV^w
this.startIndex = 0; hGzj}t
W8d
elseif(startIndex >= totalCount) Wny{qj)=
this.startIndex = indexes UF0PWpuO
,Y}HP3
[indexes.length - 1]; Q?Q!D+~mND
elseif(startIndex < 0) _jP]ifu`
this.startIndex = 0; +AXui|mn
else{ "-\I?k
this.startIndex = indexes -k!UcMWP
3M/kfy
[startIndex / pageSize]; \vpUl
} $1/yc#w
u
} joYj`K
{QJJw}!#
publicint getNextIndex(){ n{=vP`V_
int nextIndex = getStartIndex() + kOeW,:&65
F d *p3a
pageSize; MT}9T
if(nextIndex >= totalCount) uBH4E;[f
return getStartIndex(); Pe~[qETv
else 8,=,'gFO
return nextIndex; 08cCrG
} eY;XF.mF
=J<3B
H^m
publicint getPreviousIndex(){ H
$XO]\
int previousIndex = getStartIndex() - G[ @RZ~o4
F7x]BeTM
pageSize; iTwb#Q=
if(previousIndex < 0) =g
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return0; 4*P#3 B'@V
else 2.qEy6
return previousIndex; o7;lR?
} YZMSiDv[e
4hz T4!15
} B/0Xqyu
,` 6O{Z~
m%]1~b}"
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抽象业务类 _Dr9 w&;<
java代码: kUGOkSP8[
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c#(Hh{0
/** -n FKP&P
* Created on 2005-7-12 xy))}c%
*/ FUzN}"\1
package com.javaeye.common.business; #9zpJ\E
:y'EIf
import java.io.Serializable; oq${}n <
import java.util.List; @<(4J
i'V("
import org.hibernate.Criteria; V^Y'!w\LGI
import org.hibernate.HibernateException; '.EO+1{a
import org.hibernate.Session; Kv0V`}<Yc
import org.hibernate.criterion.DetachedCriteria; ,_iq$I;
import org.hibernate.criterion.Projections; ~-R%m
import )G#mC0?PV
@@JyCUd
org.springframework.orm.hibernate3.HibernateCallback; .V4-
import 4>A|2+K\
>3ax `8
org.springframework.orm.hibernate3.support.HibernateDaoS A]Bf&+V
wXjidOd$
upport; w=pr?jt1:
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import com.javaeye.common.util.PaginationSupport; G/*;h,NbNr
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public abstract class AbstractManager extends jr,N+K(@T
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HibernateDaoSupport { _Jy7` 4B.
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privateboolean cacheQueries = false; pO_IUkt
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privateString queryCacheRegion; aaP_^m O
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publicvoid setCacheQueries(boolean 6<EGH*GQ$
rtS' 90`
cacheQueries){ D/?Ec\t
this.cacheQueries = cacheQueries; g5
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} T'9ZR,{F
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publicvoid setQueryCacheRegion(String vfc:ok 1
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queryCacheRegion){ w9{C"K?u=
this.queryCacheRegion = 2 /FQ;<L
+LF#XS@
queryCacheRegion; RN[I%^$"
} E7t;p)x
,$0-I@*V
publicvoid save(finalObject entity){ XEgJ7h_
getHibernateTemplate().save(entity); MfP)Pk5
} z@yTkH_
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publicvoid persist(finalObject entity){ *!%lBt{2
getHibernateTemplate().save(entity); Lm
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} CZ<T@k
{uj_4Ft
publicvoid update(finalObject entity){ H+4j.eVzZU
getHibernateTemplate().update(entity); ]3rVULU"K-
} ]1|P|Jp
8.i4QaU
publicvoid delete(finalObject entity){ !R=@Nr>
getHibernateTemplate().delete(entity); v1TFzcHl<
} Snx!^4+MF
TxX =(7V
publicObject load(finalClass entity, b6bs .
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finalSerializable id){ !cwZ*eM
return getHibernateTemplate().load +!/ATR%Uci
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(entity, id); zaqX};b
} BmG(+;;&
*'?7OL
publicObject get(finalClass entity, FEaT}/h;
*yu}e)(0
finalSerializable id){ WMSJU/-P
return getHibernateTemplate().get AcC &Q:g
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(entity, id); XBQt:7[<
} UEU/505
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publicList findAll(finalClass entity){ ,o&C"sb
return getHibernateTemplate().find("from 7?$?Yu
Y`;}w}EcgR
" + entity.getName()); c0qp-=^&.
} \^x{NV@v42
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publicList findByNamedQuery(finalString
=<HDek
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namedQuery){ WsI`!ez;D
return getHibernateTemplate WYw#mSp
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().findByNamedQuery(namedQuery); ~r1pO#r-
} |$RNY``J
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publicList findByNamedQuery(finalString query, A,}M ^$@
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finalObject parameter){ r|Ui1f5
return getHibernateTemplate TNX9Z)=>g
b;k+N`
().findByNamedQuery(query, parameter); ag-A}k>v
} H_+n_r*
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publicList findByNamedQuery(finalString query, v pI9TG
oBzl=N3<
finalObject[] parameters){ c8l>OS5i3_
return getHibernateTemplate d2rs+-
:|S zD4Ag
().findByNamedQuery(query, parameters); }9~^}99}
} XzUGlrp:Y#
~>2uRjvkwB
publicList find(finalString query){ AK:cDKBO
return getHibernateTemplate().find iOE. .xA:
z _!ut
(query); Cf{F"o
} rQ;w{8J\t
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publicList find(finalString query, finalObject k6G
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^h(wi`i
parameter){ QV;o9j
return getHibernateTemplate().find =2Y;)wrF
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(query, parameter); Dl,QCZeM
} ajYe?z
1b,a3w(:1
public PaginationSupport findPageByCriteria Q8p6n
6{Wo5O{!\
(final DetachedCriteria detachedCriteria){ dC11kqqj
return findPageByCriteria Dk1& <} I
G7Nw}cVJ)
(detachedCriteria, PaginationSupport.PAGESIZE, 0); b}e1JPk}!
} v2T2/y%
4aW@c<-r?
public PaginationSupport findPageByCriteria 20:F$d
oA1_W).wJ
(final DetachedCriteria detachedCriteria, finalint Kxe\H'rR
Y.:R-|W
startIndex){ 8tY>%A~^z
return findPageByCriteria q
z)2a2C
&2'-v@kK
(detachedCriteria, PaginationSupport.PAGESIZE, @[GV0*yz$
sNf& "C!;
startIndex); L/3A g*
]
} ;>6< u.N
UaT%tv>}8#
public PaginationSupport findPageByCriteria z;OYPGvkw
)SV.|
(final DetachedCriteria detachedCriteria, finalint "c^! LV
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pageSize, blO4)7m
finalint startIndex){ aSR-.r
return(PaginationSupport) m</m9h8
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getHibernateTemplate().execute(new HibernateCallback(){ )"?4d[ 5
publicObject doInHibernate m/HT3<F
3JazQU
(Session session)throws HibernateException { sp K8^sh
Criteria criteria = EF/d7
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detachedCriteria.getExecutableCriteria(session); ]a3$hAcj6"
int totalCount = $8EEtr,!
8}/DD^M
((Integer) criteria.setProjection(Projections.rowCount s!6lZ mPM
{Jr1K,
()).uniqueResult()).intValue(); K_Y-N!h
criteria.setProjection 7h'
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bM W|:rn
(null); oFk2y ^>u
List items = C6+ 5G-Z
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criteria.setFirstResult(startIndex).setMaxResults _3IT3mb2n
,EqQU|
(pageSize).list(); 4.A^5J'W
PaginationSupport ps = B|`?hw@g+
/2^L;#
new PaginationSupport(items, totalCount, pageSize, ew;;e|24
Iix,}kzss
startIndex); Bk8}K=%w
return ps; }D1x%L
} q~{)
{t;
}, true); Iu'9yb
} 7UTfafOGX
c~|(j \FI
public List findAllByCriteria(final p.8 bX
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DetachedCriteria detachedCriteria){ UB~K/r`.|
return(List) getHibernateTemplate HZrA}|:h
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().execute(new HibernateCallback(){ S!K<kn`E3
publicObject doInHibernate O]: 9va
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(Session session)throws HibernateException { c!w[)>v
Criteria criteria = VoCg,gow
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detachedCriteria.getExecutableCriteria(session); w4
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2
return criteria.list(); #N{]
} G1|1Z5r
}, true); Va!G4_OT
} qI'pjTMDY
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public int getCountByCriteria(final <Bo\a3Z
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DetachedCriteria detachedCriteria){ t{;2$z 0
Integer count = (Integer) .Ys
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5(~Lr3v0
getHibernateTemplate().execute(new HibernateCallback(){ hcVu`B n
publicObject doInHibernate Y9BQLu4F
[;m@A\F
(Session session)throws HibernateException { he|Q(?
Criteria criteria = LhG\)>Y%
z ]f(lwo{
detachedCriteria.getExecutableCriteria(session); S1|5+PPs
return bQD8#Ml1
*eg0^ByeD
criteria.setProjection(Projections.rowCount ):N#X<b':
81nD:]7
()).uniqueResult(); loA/d
} y;o - @]
}, true); AojL4H|
return count.intValue(); $yU
5WEX
} >/ _#+,
} Z/,R{Jgt"
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Y"
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b}TvQ+W]2
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YCRE- 5!
用户在web层构造查询条件detachedCriteria,和可选的 2]kGDeSr
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 eipg,EI
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PaginationSupport的实例ps。 ;_\yg)X,
;PaU"z+Je~
ps.getItems()得到已分页好的结果集 0SvPr[ >
ps.getIndexes()得到分页索引的数组 ]RAh['u|
ps.getTotalCount()得到总结果数 k, N{
ps.getStartIndex()当前分页索引 I^EZ s6~
ps.getNextIndex()下一页索引 0
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ps.getPreviousIndex()上一页索引 fTXip)n!r
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 .@fA_8
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 Sm<*TH!\n_
?j8!3NCl}
一下代码重构了。 T1q27I
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我把原本我的做法也提供出来供大家讨论吧: 56JQ h
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首先,为了实现分页查询,我封装了一个Page类: ^?RH<z
java代码: ,KJHY m=Q
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/*Created on 2005-4-14*/ |\dv$`_T
package org.flyware.util.page; vyDxX
^vMlRt;
/** HL&HY)W1gf
* @author Joa V?dwTc
* yZ{yzv'D&
*/ 6 eryf?
publicclass Page { ]+Lr'HF
,r*Kxy
/** imply if the page has previous page */ IDn<5#
privateboolean hasPrePage; 1q(Qr
h
N `:MF 9
/** imply if the page has next page */ C W#:'
privateboolean hasNextPage; v4hrS\M
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/** the number of every page */ *-PjcF}Y
privateint everyPage; Jy/<
{7j
1iY4|j;ahV
/** the total page number */ xI{fd1
privateint totalPage; FWJ**J
\_O#M
/** the number of current page */ f|VCi bI
privateint currentPage; keLeD1
!*Is0``
/** the begin index of the records by the current =V|jd'iwx
p#jAEY p
query */ F}{%*EJ
privateint beginIndex; <c[\\
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dJ
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/** The default constructor */ Qu[QcB{ro-
public Page(){ ;+XrCy!.)L
pk9Ics;y
} s>o#Ob@4'
2|^@=.4\
/** construct the page by everyPage \1G'{#Q
* @param everyPage 0Qa0
* */ FA*$ dwp
public Page(int everyPage){ F8Ety^9>9
this.everyPage = everyPage; r|UJJ9i
} NH|I>vyN
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/** The whole constructor */ k5E2{&wZ
public Page(boolean hasPrePage, boolean hasNextPage, xx!8cvD4?
=(
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int everyPage, int totalPage, =xm7i#1
int currentPage, int beginIndex){ +Mq\3
this.hasPrePage = hasPrePage; TiI /I`A
this.hasNextPage = hasNextPage; IMwV9rF
this.everyPage = everyPage; 3`yO&upk
this.totalPage = totalPage; ?)-6~p 4N
this.currentPage = currentPage; 73rme,
this.beginIndex = beginIndex; eZOR{|z
} DWOf\[
`B@eeXa;u
/** 5(ZOm|3ix
* @return :|s;2Y
* Returns the beginIndex. 7he,(V
*/ ybiTWM
publicint getBeginIndex(){ Zq8 5q
return beginIndex; 4Y?2u
} nrKAK^
;/$pxD
/** GKIzU^f
* @param beginIndex vU,7Y|t`
* The beginIndex to set. yS~Y"#F!.
*/ 'Hx#DhiFz
publicvoid setBeginIndex(int beginIndex){ U\lbh;9G
this.beginIndex = beginIndex; w>j5oz}
} jdG2u
p
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/** 2*V%S/cck
* @return wA$7SWC
* Returns the currentPage. ?I^$35
*/ .zZfP+Q]8
publicint getCurrentPage(){ I%r7L
return currentPage; Ld*Ds!*'/
} o4p5`jOG@
;>Z+b#C[
/** M
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* @param currentPage 9ia&/BT7"z
* The currentPage to set. B0b|+5WhR
*/ !O"2)RU1
publicvoid setCurrentPage(int currentPage){ A x8 >
this.currentPage = currentPage; I*TTD]e'X
} aQmS'{d?^
@@\qso
/** 9e`};DE
* @return *Hn=)q
* Returns the everyPage. m#BXxS#B<_
*/ x~}&t+FK
publicint getEveryPage(){ gH(#<f@ZI
return everyPage; uB"B{:Kz
} ~s&r.6DW
v+x<X5u
/** m&=Dy5
* @param everyPage EgG3XhfS
* The everyPage to set. 4Mg%}/cC
*/ vGsAM*vw6
publicvoid setEveryPage(int everyPage){ f`ibP6%
this.everyPage = everyPage; -_9*BvS]R
} tb?TPd-OY
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/** D6lzcf
* @return AB%i|t
* Returns the hasNextPage. 40=u/\/K
*/ jjH2!R]^>
publicboolean getHasNextPage(){ ih)\P0wed
return hasNextPage; 3 8&K"
} }f;TG:6
g
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/** J;XO1}9
* @param hasNextPage nnhI]#,a{
* The hasNextPage to set. U^[AW$WzU
*/ E2}X[EoBF
publicvoid setHasNextPage(boolean hasNextPage){ U4dfO=
this.hasNextPage = hasNextPage; 9+*{3 t
} OD[=fR|cp
T] H'l
/** mW)kWuOO
* @return [H!do$[>
* Returns the hasPrePage. %ho?KU2j
*/ *lZ V3F
publicboolean getHasPrePage(){ GNHXtu6
return hasPrePage; _0
43,
} IX
6 jb"
0ie)$fi
/** ,e 7
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* @param hasPrePage ,b^jAzow
* The hasPrePage to set. B:i$
*/ 9`qw,X&AK_
publicvoid setHasPrePage(boolean hasPrePage){ PY4">~6\i
this.hasPrePage = hasPrePage; \COoU("
} ' p!&&.%
JI-.SR
/** 3r^||(_u
* @return Returns the totalPage. k=d_{2 ~
* -{A64gfFxT
*/ .+8#&Uy
publicint getTotalPage(){ m_ wvi
return totalPage; 3&[ d.,/
} XpKeN2=p
xzx~H>M
/** Mf5*Wjz.Mc
* @param totalPage H_8PK$c;
* The totalPage to set. ZBK)rmhMx
*/ vfDX~_N
publicvoid setTotalPage(int totalPage){ V@G|2ZI
this.totalPage = totalPage; p+nB@fN/
} o@$pyU8
OWr\$lm@z$
} B&!>& Rbx
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q2Sc{E>[
M_$;"NS+}
1,P2}mYv
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 ?:vB_@
iH)vLD
个PageUtil,负责对Page对象进行构造: rV%;d[LB
java代码: w2!5TKZ`
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l,QO+
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/*Created on 2005-4-14*/ PEtr8J$uB
package org.flyware.util.page; bV)h\:oC
W-1Ub |8C
import org.apache.commons.logging.Log; LmR OG-9
import org.apache.commons.logging.LogFactory; n#P?JyGm1g
8"wavh|g4
/** V22Br#+
* @author Joa J
rYL8 1
* S6yLq|W0
*/ ~^~+p
publicclass PageUtil { DQN"85AIZ
1$yS Ii
privatestaticfinal Log logger = LogFactory.getLog !*k'3rKOW
tD,~i"0;
(PageUtil.class); S:
g 2V
RL"hAUs_1
/** :WSszak
* Use the origin page to create a new page tF!C']
* @param page j{%'A
* @param totalRecords 2+\@0j[q
* @return f1Gyl
*/ M1Th~W9l
publicstatic Page createPage(Page page, int w4uY/!~k
c#[d7t8ONe
totalRecords){ rY=dNK]d
return createPage(page.getEveryPage(), <qx qlEQT
4':U rJ+
page.getCurrentPage(), totalRecords); Bp=BRl
} HqA~q
Zdu8axK:
/** 6~8X/
-02
* the basic page utils not including exception 5[$Tpn#K7
\v.YP19
handler ='.G,aJ9
* @param everyPage 5AAPtZ\lH
* @param currentPage 1GgG9I
* @param totalRecords upF^k%<y:
* @return page uI&<H T?
*/ cD4H@!=a
publicstatic Page createPage(int everyPage, int 8:Jc2K
x4S0C[k
currentPage, int totalRecords){ zJtB?<
everyPage = getEveryPage(everyPage); X7 fJ+Cn
currentPage = getCurrentPage(currentPage); vM/D7YS:
int beginIndex = getBeginIndex(everyPage, k3B]u.Lo
U3ao:2zP
currentPage); $x1PU67
int totalPage = getTotalPage(everyPage, ew6\Z$1c~
9|LV
x3]
totalRecords); zF=E5TL-,4
boolean hasNextPage = hasNextPage(currentPage, 8G
p%Q
=5X(RGK
totalPage); ' +[fJ> Le
boolean hasPrePage = hasPrePage(currentPage); &H@OLyC
/M8&`
returnnew Page(hasPrePage, hasNextPage, D|R,$v:
everyPage, totalPage, G~Mxh,aD$>
currentPage, LIDYKKDJ^
ZzV%+n7<Vx
beginIndex); G8voqP
} i\u m;\
h"+|)'*n
privatestaticint getEveryPage(int everyPage){ $X:r&7t+Q[
return everyPage == 0 ? 10 : everyPage; zkRL'-
} } h0
)
(# ;<iu}
privatestaticint getCurrentPage(int currentPage){ `(7HFq<N
return currentPage == 0 ? 1 : currentPage; WAt | J2
} A#B6]j)
/iekww^54
privatestaticint getBeginIndex(int everyPage, int G_UxR9Qo
$f^ \fa[
currentPage){ Kn<z<>vO
return(currentPage - 1) * everyPage; 89{@ 2TXR
} }vLK-Vv
'v*Y7zZ#K
privatestaticint getTotalPage(int everyPage, int >B9|;,a
?3
l4U
totalRecords){ g0BJj=
int totalPage = 0; K 6Gri>Um
'cx&:s
if(totalRecords % everyPage == 0) d;D8$q)8Q
totalPage = totalRecords / everyPage; * -Kf
else AK*F,H9
totalPage = totalRecords / everyPage + 1 ; S4?N_"m9
!@x'?+
return totalPage; m
pWmExQ
} hh!^^emo
Iq-+X3i
privatestaticboolean hasPrePage(int currentPage){ ,\BGxGNAmV
return currentPage == 1 ? false : true; Uxq9H
} G=lket6
i$A0_ZJKjZ
privatestaticboolean hasNextPage(int currentPage, W1
qE,%cx
)"IBw0]
int totalPage){ n^Qt !~
return currentPage == totalPage || totalPage == <d\Lvo[
Gn*vVZ@`x
0 ? false : true; d|9B3I*I
} Q( C\X
4ISZyO=
%y/8i%@6
} >~kSe=Hsb4
q>T7};5m2
Ifm|_
0!c^pOq6
cj:!uhZp7
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。 Q_bF^4gt
eJB !|
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 {:VUu?5-t;
v}v! hs Q
做法如下: 2sJj -3J
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]Y'oxh
Khbkv
的信息,和一个结果集List: =U6%Wdth
java代码: s:j"8ZH
t$sL6|Ww}o
>4A~?=
/*Created on 2005-6-13*/ / ;U
package com.adt.bo; yB&+2
vxxa,KR/y
import java.util.List; asDq(J`sQ
Xj/U~
import org.flyware.util.page.Page; o5(p&:1M
eGZX6Q7m
/** kMGK8y
* @author Joa :HrD[KT
*/ ps#+i
publicclass Result { 'sCj\N
YlW~
private Page page; F)we^'X
G:f\wK[
private List content; 'E2\e!U/
AnV\{A^
/** Z&hzsJK{m$
* The default constructor pSQ)DqW
*/ 78v4cQ Y
public Result(){ WxE4r
super(); <_HK@E<_HO
} 3"O)"/"Q.
#On EQ:
/** Vy-EY*r|
* The constructor using fields &TqY\l
* ;\@co5.=
* @param page ~c~$2Xo
* @param content PiD%PBmUl
*/ HH>"J/;c,
public Result(Page page, List content){ cTO\Vhg
this.page = page; 8Wn;U!qT
this.content = content; wN [mU
} ;2||g8'
-c-#1_X5
/** C WJGr:}&
* @return Returns the content. {Mc^[}9
*/ :` >|N|i
publicList getContent(){ V[<]BOM\v
return content; s)#8>s -
} {{b&l!
RbUhLcG5
/** 0n25{N
* @return Returns the page. 0f.rjd
*/ d\Xi1&&
public Page getPage(){ 9$&+0
return page; xtef1 8i>
} 1Ih.?7}
I\JJ7/S`t
/** 5!2^|y4r
* @param content *Mf;
* The content to set. oVPtA@
*/ <eU28M?\
public void setContent(List content){ FNpMu3Q
this.content = content; +@]b}W
} t:tT Zh
=%,;=4w
/** ITj0u&H:
* @param page c[:OK9TH
* The page to set. SG1o<#>
*/ $dAQ'\f7
publicvoid setPage(Page page){ HC0q_%j
this.page = page; aa8xo5tIp
} gxEa?QH
} -!uut7Z|
YNc]x>
P+iZ5S\kL=
6LUO
c}iVBN6~.<
2. 编写业务逻辑接口,并实现它(UserManager, yc.Vm[!
UGuEZ-r
UserManagerImpl) V[f-Nj Kf
java代码: Ue:'55
7^|oO~x6
<3dmY=
/*Created on 2005-7-15*/ i6R2R8
package com.adt.service; e0O2>w
Z%3]
import net.sf.hibernate.HibernateException; Ekx3GM_]
o]0v#2l'
import org.flyware.util.page.Page; 2@``=0z
K31G>k@
import com.adt.bo.Result; p[BF4h{E
LG6VeYe|\X
/** 6QsH?!bu
* @author Joa 3L$_OXx
*/ -%]O-'
publicinterface UserManager { %(a<(3r
a!MhxM5
public Result listUser(Page page)throws L8K=Q
5y7rY!]Bf
HibernateException; #3@ Du(_n
2j_YHv$I
} ahi lp$v
;SAurG$
uU v yZ
&fJ92v?%^S
Fy|tKMhnc
java代码: T9r"vw
:[:5^R
6e,|HV
/*Created on 2005-7-15*/ y9d[-j
;w
package com.adt.service.impl; mA|&K8H
y:Xs/RS
import java.util.List; L/1zG/@
l2uh"!
import net.sf.hibernate.HibernateException; (vm&&a@
fMe "r*SU
import org.flyware.util.page.Page; ugexkdgM
import org.flyware.util.page.PageUtil; Xg:w;#r,
*<k8H5z8]
import com.adt.bo.Result; ;K<e]RI;?
import com.adt.dao.UserDAO; F&US-ce:M
import com.adt.exception.ObjectNotFoundException; fUQuEh5_
import com.adt.service.UserManager; q[4{Xh
\F]X!#&+
/** )(~s-x^\z@
* @author Joa oJC-?
*/ OgJd^
publicclass UserManagerImpl implements UserManager { su]CaHU
lqFDX
d
private UserDAO userDAO; ;cQhs7m(9
NpV#zzE
/** (Fq|hgOA>M
* @param userDAO The userDAO to set. s(*LV2fa
*/ :5!>h8p;
publicvoid setUserDAO(UserDAO userDAO){ Jlw<%}r
this.userDAO = userDAO; 9{{QdN8
} 2N_8ahc
=}N&c4I[j
/* (non-Javadoc) Gt4| ]
* @see com.adt.service.UserManager#listUser {~.~ b+v
"&jA
CI
(org.flyware.util.page.Page) )%rGD
=2~
*/ QC7Ceeh]4
public Result listUser(Page page)throws R;,&s!\<
n4Fh*d ixg
HibernateException, ObjectNotFoundException { 8A/;a{
int totalRecords = userDAO.getUserCount(); Wyu$J
if(totalRecords == 0) R?"sM<3`e
throw new ObjectNotFoundException P7GuFn/p~2
zbH Nj(~
("userNotExist"); q)%F#g
page = PageUtil.createPage(page, totalRecords); "Y(stRa
List users = userDAO.getUserByPage(page); yl|?+
returnnew Result(page, users); MhMY"bx8
} )cA#2mlS'1
Jy&O4g/'5
} [{.e1s<EK
Q 6djfEN>
OiI[w8
#<ppiu$
r|$@Wsb?#
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ~(E.$y7P
}{>)2S
询,接下来编写UserDAO的代码: tL0<xGI5^
3. UserDAO 和 UserDAOImpl: qfp,5@p
java代码: b&:>v9U
+a$'<GvP
#/fh_S'Z
/*Created on 2005-7-15*/ O~t]:p9_
package com.adt.dao; 4]L5%=atn
N@D]Q&;+(T
import java.util.List; 8S2sNpLi-g
*`~
woF
import org.flyware.util.page.Page; dQUZ11
^z&eD,
import net.sf.hibernate.HibernateException; -2NXQ+m ;
{)j~5m.,/o
/** Oax*3TD
* @author Joa #+)AIf
*/ I&9_F%rX
publicinterface UserDAO extends BaseDAO { "YU<CO;4VV
}SL&Y `Y]
publicList getUserByName(String name)throws hV5Aw;7C
3vx5dUgl,
HibernateException; 6H+'ezM
r!H'8O!
publicint getUserCount()throws HibernateException; (,Zy2wr=
+/u)/ey
publicList getUserByPage(Page page)throws `Y HnL4
<a9<rF =r
HibernateException; ?f@g1jJP
>b2j j+8
} |C:^BWrU*
-$W#bqvz^
V_b"^911r
>*DR>U
Hh^EMQk
java代码: }xZR`xP(
wOW#A}m'vj
JbT+w\o
/*Created on 2005-7-15*/ Ul"9zTH
package com.adt.dao.impl; U^qQ((ek
=Uy;8et
import java.util.List; r6
k/QZT
,4kly_$BH
import org.flyware.util.page.Page; ?`9XFE~a!
[bE-Uu7q5P
import net.sf.hibernate.HibernateException; [k1N-';;;
import net.sf.hibernate.Query; JQ5E; 8J>
?D 8<}~Do
import com.adt.dao.UserDAO; 9f UD68Nob
MNC=r?
/** jb0wP01R
* @author Joa 9;W2zcN
*/ WBb@\|V|
public class UserDAOImpl extends BaseDAOHibernateImpl 91I6-7# Xt
;Fo%R$y
implements UserDAO { .bdp=vbA
\"]KF8c^_
/* (non-Javadoc) %"<|u)E
* @see com.adt.dao.UserDAO#getUserByName 7rIz
++9?LH4S4
(java.lang.String) }%8 :8_Ke
*/ L{pz)')I
publicList getUserByName(String name)throws #@pgB:~lB
QoLp$1O(y
HibernateException { ?<F=*eS
String querySentence = "FROM user in class [j3-a4Wu
_#\e5bE=Z
com.adt.po.User WHERE user.name=:name"; I |PEC-(
Query query = getSession().createQuery + 6noQYe
RB\
Hl
(querySentence); ppm=o4`s[
query.setParameter("name", name); <bSG|VqnH
return query.list(); lw\+!}8(
} X| !VjUH
8k( zU>^
/* (non-Javadoc) LiG!xs
* @see com.adt.dao.UserDAO#getUserCount() [c^!;YBp)
*/ G_m $?0\
publicint getUserCount()throws HibernateException { kC,=E9)O
int count = 0; v9,<2
String querySentence = "SELECT count(*) FROM x5w5xw
|mM K9OEu
user in class com.adt.po.User"; ;\]&k
Query query = getSession().createQuery *&vlfH
f: 9bq}vH
(querySentence); 6N49q-.Lg
count = ((Integer)query.iterate().next TdU'L:<4l
c>|1%}"?
()).intValue(); cp:U@Nh(
return count; 40e(p/Qka
} bmOK8
\DiAfx<Ub
/* (non-Javadoc) }s7@0#j@a
* @see com.adt.dao.UserDAO#getUserByPage OXxgnn>W'
FNN7[ku!
(org.flyware.util.page.Page) +TZVx(Z&A
*/ Af"p:;^z
publicList getUserByPage(Page page)throws \?D~&d,a=
oW5Ov
HibernateException { 70GwTK.{~
String querySentence = "FROM user in class =.`:jZG
|Q(3rcOrV"
com.adt.po.User"; pqCp>BO?O
Query query = getSession().createQuery C3K":JB
!V'~<&
(querySentence); }ed{8"bj
query.setFirstResult(page.getBeginIndex()) .9u0WP95
.setMaxResults(page.getEveryPage()); 2M+}o"g
return query.list(); lC=-1*WH
} 9bQD"%ha=d
<e?1&5 6
} 4<j7F4
*V`E)maU
;b5^)S
M=M~M$K
s||c#+j"8
至此,一个完整的分页程序完成。前台的只需要调用 >"q?P^f/
eP|_
userManager.listUser(page)即可得到一个Page对象和结果集对象 yMz dM&a!*
}Ug O$1
的综合体,而传入的参数page对象则可以由前台传入,如果用 Q\nIU7:bZ
@CtnV|
webwork,甚至可以直接在配置文件中指定。 Akdx1h,
u}">b+{!
下面给出一个webwork调用示例: H %Dcp#k
java代码: [$DI!%e|
zNO,vR[\
x
MFo
/*Created on 2005-6-17*/ U>i}C_7g
package com.adt.action.user; /u&7!>,
0;L.h|R T(
import java.util.List; 6J]8BHJn+
?$ Dc>
import org.apache.commons.logging.Log; jK]An;l{Z
import org.apache.commons.logging.LogFactory; p[K!.vOt+
import org.flyware.util.page.Page; tZ.hSDH
=E$B0^_2RC
import com.adt.bo.Result; NY
GWA4L
import com.adt.service.UserService; m;JB=MZ=m
import com.opensymphony.xwork.Action; X%98k'h.y
?orLc,pU^
/** b&*)C#7/T
* @author Joa ;d.gVR_V
*/ V2SHF
publicclass ListUser implementsAction{ Q-?6o
m@y<wk(
privatestaticfinal Log logger = LogFactory.getLog ;lQ>>[*
!{?<(6;t
(ListUser.class); +,_%9v?3
K,o&gY
private UserService userService; KTE X]
V6bjVd9|Z
private Page page; )*L=$0R
O'{g{
privateList users; J)EL<K$Z[
YmwXA e:
/* :CsrcT=
* (non-Javadoc) 6IJH%qUx'
* ]P96-x
* @see com.opensymphony.xwork.Action#execute() wu. >'v?y
*/ z+K1[1SM
publicString execute()throwsException{ \iA.{,VX
Result result = userService.listUser(page); 9DmFa5E
page = result.getPage(); Yw6uh4
users = result.getContent(); [NK&s:wMk
return SUCCESS; 0}"'A[xE
} Db*&'32W
I uC7Hx`z
/** cR=o!2O
* @return Returns the page. tZY6{,K%4
*/ ;YZ'd"0v
public Page getPage(){ )~CNh5z6Y
return page;
(F&o!W
} P
@~) 9W
MnP+L'|
/** T930tX6"h
* @return Returns the users. 6lL^/$]
*/ Js&.p9S2
publicList getUsers(){ `<6FCn4{X
return users; VsDY,=Ww
} 0$_WIk
h!7Lvh`o
/** hGcu(kAC,
* @param page 9TZ 6c
* The page to set. eVzZfB-=4}
*/ r%9=75HA
publicvoid setPage(Page page){ Wjli(sT#-
this.page = page; $|N\(}R
} {TvB3QOsj
ovZ!}
/** )|GYxG;8C
* @param users {mB!mbr
* The users to set. Y(Y#H$w
*/ ]QQeUxi
publicvoid setUsers(List users){ FzAzAl5
this.users = users; ,F n-SrB:
} ?aguAqG$
;?y~ h$
/** #itZ~tol
* @param userService =imJ0V~RW
* The userService to set. /i{V21(%
*/ ^mouWw)a_
publicvoid setUserService(UserService userService){ TPYh<p#
this.userService = userService; >2ha6A[
} iqFC~].)
} KV! (
Q\}Ck+d`a
=y=MljEX
&(m01
Hp*N%
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, -@XOe&q
AwZz}J+
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 Ph)>;jU
S~>R}=
么只需要: J06D_'{
java代码: $EL:Jx2<
!;Ke# E_d
hrGX65>
<?xml version="1.0"?> %/d1x
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork s{*bFA Z1F
Z)f?X
1.0//EN" "http://www.opensymphony.com/xwork/xwork- {&a6<y#-
^b4i9n,t1
1.0.dtd"> m
?*h\NaB
5?0~7^de
<xwork> 211V'|a_>
{q^UWv?1
<package name="user" extends="webwork- 4(,M&NC
xW7[ VTXc^
interceptors"> [c
XSk
j<k-w
<!-- The default interceptor stack name [
P,gEYk
y#= j{
--> FV{XPr%
<default-interceptor-ref "ji+~%`^[t
L#%)@
name="myDefaultWebStack"/> Cu_-QE
n(i/jW~0w
<action name="listUser" rM?
J40&.
M@Ti$=
class="com.adt.action.user.ListUser"> v57<b&p26
<param F3tIJz>3
Qkw?QV-`k
name="page.everyPage">10</param> k9;t3-P
<result %j2$ ezud
3#Iq5vT
name="success">/user/user_list.jsp</result> YABi`;R]'
</action> de;CEm<n
Vt,P.CfdC
</package> zZP/C
5#y_EpL"
</xwork> Zy.3yQM9i
B*9?mcP\
aj/+#G2
d%RH]j4
9aX!<Z
#$]8WSl
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ou{V/?rb
:,
3S5!(y
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 :^-\KE`3
<\eRa{ef
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 { `xC~B h
[KCR@__
)[u'LgVN/L
~Orz<%k.
X4+H8],)
我写的一个用于分页的类,用了泛型了,hoho R&$fWV;'
Xoha.6$l5
java代码: !R@jbM
,9MNB3
oS}fr?
package com.intokr.util; 5"(FilM
abCxB^5VL
import java.util.List; CNhLp#
G(ZEP.h`u
/** FGhnK'
* 用于分页的类<br> A~^x*#q{4
* 可以用于传递查询的结果也可以用于传送查询的参数<br> NNwGRoDco
* 4TYtgP1
* @version 0.01 j WMTQLE.
* @author cheng *Vg) E*s
*/ :DeJnE
public class Paginator<E> { eNO[ikm
privateint count = 0; // 总记录数 +1@'2w{
privateint p = 1; // 页编号 ;.b^&h
privateint num = 20; // 每页的记录数 &aa3BgxyE
privateList<E> results = null; // 结果 -%Rbd0gVH\
awjAv8tPO!
/**
}Oqt=Wm
* 结果总数 kB%.i%9\\
*/ }8s&~fH
publicint getCount(){ _g-0"a{-
return count; _^`V0>Mh:
} &0H_W xKeB
Z3=N= xY]
publicvoid setCount(int count){ V-E 77u6{0
this.count = count; S<-5<Pg
} 9}L2$^#,NA
3}fhU{-c
/** G}LV"0?
* 本结果所在的页码,从1开始 b|;h$otC
* NqveL<r`
* @return Returns the pageNo. {wgq>cb
*/ JT~Dr KI_
publicint getP(){ jQ7-M4qO/
return p; ==oJhB
} fL("MDt
cd=K=P}p
/** rq Uk_|Xa
* if(p<=0) p=1 /0$405
* 8TK*VOf`
* @param p gv D*^
*/ kP5G}Bp
publicvoid setP(int p){ EziGkbpd@
if(p <= 0) I Gi9YpI&K
p = 1; -@Urq>^v T
this.p = p; Qpj[]c5
} ReL+V
*B84Y.d f
/** M*C1QQf\N
* 每页记录数量 MmePhHf
*/ a.RYRq4o
publicint getNum(){ &49WfctT
return num; $DtUTh3)
} z@V9%xF-3
t* p%!xsH
/** /Ahh6=qQY
* if(num<1) num=1 #&fu"W+D96
*/ nR w f;K
publicvoid setNum(int num){ Aa]3jev
if(num < 1) Q1x15pVku/
num = 1; D;jbZ9
this.num = num; s:(z;cj/
} 'KT(;Vof
_OS,zZ0
/** [7g-M/jvY
* 获得总页数 FC||6vJth
*/ N9y+Psh
publicint getPageNum(){ W-Vc6cq
return(count - 1) / num + 1; K5t.OAA:
} Fs(S!;
"dE[X`
}=
/** )qOcx
I
* 获得本页的开始编号,为 (p-1)*num+1 H
SGz-
*/ ,A)Z.OWOq
publicint getStart(){ ET 0(/Zz
return(p - 1) * num + 1; -YmIRocx
} 2JcP4!RD
3 `mtc@*
/** >,I'S2_Zl
* @return Returns the results. #6l(2d
*/ O6ugN-d>
publicList<E> getResults(){ M%W#0
return results; 7s!rer>
} AT1{D!b
;:+2.//
public void setResults(List<E> results){ n}fV$qu
this.results = results; yy&L&