Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .0>2j(
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &I$MV5)u
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 WD7IF+v
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 >FabmIcC
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。 Q-}yZ
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分页支持类: Th6xwMq
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java代码: %Z=%E!*
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package com.javaeye.common.util; a.yCd/
@Js^=G2
import java.util.List; af<R.
2\p8U#""
publicclass PaginationSupport { 9zKrFqhNo
r2]KP(T8|
publicfinalstaticint PAGESIZE = 30; EBX+fzjQo
>qBQfz:U>
privateint pageSize = PAGESIZE; hY@rt,! 8
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privateList items; M_wj>NXZ
#DI%l`B
privateint totalCount; yIL6Sb
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privateint[] indexes = newint[0]; l$~3_3+
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privateint startIndex = 0; eI7FbOze
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public PaginationSupport(List items, int uwcm%N;I"
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totalCount){ 8AK=FX&@&
setPageSize(PAGESIZE); 0Y81B;/F
setTotalCount(totalCount); }9GD'N?4
setItems(items); |ZAR!u&0
setStartIndex(0); 5DEK`#*
} 0 xUw}T6
O#g'4 S
public PaginationSupport(List items, int U$fh ~w<[
q`l%NE
totalCount, int startIndex){ dp3>G2Yq
setPageSize(PAGESIZE); ?W*{%my
setTotalCount(totalCount); ;|.^_Xs
setItems(items); J.r^"K\
setStartIndex(startIndex); -r6cK,WVU
} t0 1@h_WS
NT6OGBl&
public PaginationSupport(List items, int 1gwnG&
"+g9}g
totalCount, int pageSize, int startIndex){ 3:Mq40]x
setPageSize(pageSize); O#,Uz2
setTotalCount(totalCount); _bi]Bpxf
setItems(items); %8_bh8g-
setStartIndex(startIndex); qW1d;pt
} arR9uxP
D+Ke)-/
publicList getItems(){ 6fozc2h@x%
return items; }Ss]/_t
} ;wi}6rF%[i
zq=X;}qYj
publicvoid setItems(List items){ a5/6DK>
this.items = items; b1(7<o
} 3 %ppvvQ
F3XB};
publicint getPageSize(){ LyaFWx
return pageSize; aL9yNj}2
} /A8ua=Kn
(aAv7kB&
publicvoid setPageSize(int pageSize){ {{G`0i2KV
this.pageSize = pageSize; B^;P:S<yG
} G234UjN%
M7O5uW`
publicint getTotalCount(){ ^usZ&9"@P
return totalCount; J4yL"iMt
} Ry@QJn I<
UE-<
publicvoid setTotalCount(int totalCount){ kK27hfsw
if(totalCount > 0){ h%9>js^~
this.totalCount = totalCount; ;"}yVV/4
int count = totalCount / >tUi ;!cQ
F3-<F_4.w
pageSize; \(ygdZ{R
if(totalCount % pageSize > 0) S_E-H.d"
count++; 0Jz5i4B
indexes = newint[count]; *Kpk1
for(int i = 0; i < count; i++){ KW* 2'C&
indexes = pageSize * {`FkiB` i
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i; yqEX0|V%
} X"4 :#s
}else{ B-oQ 9[~
this.totalCount = 0; rd*`8B
} 8T7ex(w
} )w?DB@Tx
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publicint[] getIndexes(){ 2
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return indexes; n(i Uc1Y
} 'jw?XtG
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publicvoid setIndexes(int[] indexes){ }?KvT$s
this.indexes = indexes; lO
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} $pKlF0 .
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publicint getStartIndex(){ +-DF3(
return startIndex; OcA_m.
} |WiE`&?xP
hA6
publicvoid setStartIndex(int startIndex){ z%)~s/2Rs
if(totalCount <= 0) 1JRM@ !x
this.startIndex = 0; rq>}]
U
elseif(startIndex >= totalCount) }ZQ)]Mr
this.startIndex = indexes YUzx,Y>k
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[indexes.length - 1]; mH1T|UI
elseif(startIndex < 0) N\,[(LbA&
this.startIndex = 0; P3Wnso
else{ PykVXZ7j;
this.startIndex = indexes ;6 ?a8t@
@q98ac*{
[startIndex / pageSize]; o1kTB&E4B
} IhIz 7.|
} %DK0s(*w0
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publicint getNextIndex(){ S!Alno
int nextIndex = getStartIndex() + q 9e(YX>
&d%\&fCm(
pageSize; *^ZJ&.
if(nextIndex >= totalCount) KKBrw+)AJ
return getStartIndex(); B(pxyv)
else &z;bX-"E
return nextIndex; TANv)&,|9
} i;flK*HOZ9
ww}4
publicint getPreviousIndex(){ r}**^"mFy
int previousIndex = getStartIndex() - Qe[ejj1o:
&RJ*DAmL
pageSize; B\73Vf
if(previousIndex < 0) kB)u@`</mV
return0; R@X65o
else ?*zDsQ
return previousIndex; l&/V4V-
} GM~Ek]9C%
t3qPocYQ
} Silh[8
X[ 6#J
OH\(;RN*
vGCvJ*4!
抽象业务类 0P5s'2w
java代码: )>=!</@
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/** 9-W3}4'e
* Created on 2005-7-12 R_4eME2LB
*/ O
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package com.javaeye.common.business; ]\C wa9
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import java.io.Serializable; [u $X.=(
import java.util.List; dwpE(G y6c
RoFOjCc>D.
import org.hibernate.Criteria; WYUel4Z
import org.hibernate.HibernateException; ( GW"iL#.
import org.hibernate.Session; [HEljEv
import org.hibernate.criterion.DetachedCriteria; /E39Z*
import org.hibernate.criterion.Projections; y}F;~H~P
import ? K ,d
;!+-fn4C
org.springframework.orm.hibernate3.HibernateCallback;
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import
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3'7] jj
org.springframework.orm.hibernate3.support.HibernateDaoS 8.!+Hm4
Ud_7>P$a
upport; I}jem
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import com.javaeye.common.util.PaginationSupport; kSpy-bVn
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public abstract class AbstractManager extends *)(S}D\94
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HibernateDaoSupport { \8Hs[H!
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privateboolean cacheQueries = false; S}b^_+UbP
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privateString queryCacheRegion; kaT
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publicvoid setCacheQueries(boolean kz*6%Cg*~
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cacheQueries){ 2oF1do;
this.cacheQueries = cacheQueries; Dr)jB*yK
} .OpG2P
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publicvoid setQueryCacheRegion(String s&4&\Aq}x#
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queryCacheRegion){ nWes,K6T
this.queryCacheRegion = iYf)FPET
8og8;#mnyr
queryCacheRegion; fm^J-
} B'e@RhU;
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publicvoid save(finalObject entity){ ;:,U]@
getHibernateTemplate().save(entity); bt};Pn{3
} SsEpuEn
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publicvoid persist(finalObject entity){ }BUm}.-{u,
getHibernateTemplate().save(entity); RW<10:
} 4?fpk9c{2
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publicvoid update(finalObject entity){ sU+8'&vBp
getHibernateTemplate().update(entity); 0v,fY2$c
} ([dwZ6$/J
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publicvoid delete(finalObject entity){ AQ?;UDqU
getHibernateTemplate().delete(entity); t#VX#dJ
} 5WA:gy gB&
/9A6"Z
publicObject load(finalClass entity, 5\EnD,y
b BiTAP
finalSerializable id){ r8tW)"?
return getHibernateTemplate().load 4T TrHs
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(entity, id); ^`[<%.
} (5;nA'
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publicObject get(finalClass entity, 2^=8~I!n&
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finalSerializable id){ NM9,AG
return getHibernateTemplate().get njZJp|y6
\:g\?[
(entity, id); 0CvGpM,
} 01&@8z'E
2acTw#
publicList findAll(finalClass entity){ 'd|!Hr<2
return getHibernateTemplate().find("from BaWU[*
*8_Dn}u?Jx
" + entity.getName()); |@~_&g
} )Ii`/I^
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publicList findByNamedQuery(finalString 73B[|J*
}d>Xh8:%)
namedQuery){ %JH/|mA&|
return getHibernateTemplate lcLDCt?
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().findByNamedQuery(namedQuery); E+ |K3EJ
} DgK*>A
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publicList findByNamedQuery(finalString query, >9mj/P D
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finalObject parameter){ d'&OEGb<
return getHibernateTemplate jhPbh5E
teI?.M9r
().findByNamedQuery(query, parameter); xC9{hXg!
} vS"h`pL
X- X`Z`o
publicList findByNamedQuery(finalString query, =1k%T {>
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finalObject[] parameters){ }]#z0'Aqsu
return getHibernateTemplate en/ h`h]h
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().findByNamedQuery(query, parameters); /CH]'u^j
} a0+q^*\d\R
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publicList find(finalString query){ o>nw~_ H\
return getHibernateTemplate().find IN@o9pUjV
h-|IZ}F7
(query); v%c/eAF
} .vctuy&
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publicList find(finalString query, finalObject mr/?w0(C
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parameter){ *N4/M%1P
return getHibernateTemplate().find 5|~nX8>
6K )K%a,9
(query, parameter); B=;kC#Emtf
} H2H[ DVKv
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public PaginationSupport findPageByCriteria d=meh4Y
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(final DetachedCriteria detachedCriteria){ rM^2yr7H
return findPageByCriteria 9-V'U\}L
t#@z_Mn\
(detachedCriteria, PaginationSupport.PAGESIZE, 0); sp:4b$zX
} :<bhQY
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public PaginationSupport findPageByCriteria $./aKJ1B
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(final DetachedCriteria detachedCriteria, finalint *r[V[9+y-D
kX+9U"`
C
startIndex){ 0;@>jo6,!
return findPageByCriteria d/jP2uuA
`A%WCd60Tc
(detachedCriteria, PaginationSupport.PAGESIZE, vb?.`B_>&
9od*N$
startIndex); c_S~{a44Ud
} #;~HoOK*#
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public PaginationSupport findPageByCriteria XVqkw@Ia4!
@8>bp#x/1
(final DetachedCriteria detachedCriteria, finalint 7M4J{}9
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pageSize, akNqSZwj
finalint startIndex){ r180vbN$
return(PaginationSupport) hSw=Oq82
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getHibernateTemplate().execute(new HibernateCallback(){ 9Q}g
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publicObject doInHibernate I<CrEL<5}~
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(Session session)throws HibernateException { 8C8S)
;
Criteria criteria = yyljyE
A.("jb@I
detachedCriteria.getExecutableCriteria(session); ye=4<b_
int totalCount = A-:k4] {%P
KpYezdPF)
((Integer) criteria.setProjection(Projections.rowCount @XolFOL"f"
&z1U0uk
()).uniqueResult()).intValue(); pZlsDM/=
criteria.setProjection $A9Pi"/*z
=k.%#h{
(null); aQ$sn<-l
List items = xSd&xwP
BCe'J!
criteria.setFirstResult(startIndex).setMaxResults ^Z#G_%\Y:
+|d]\WlJ
(pageSize).list(); [.fh2XrVM
PaginationSupport ps = "Kp#Lx
@L~erg>8=
new PaginationSupport(items, totalCount, pageSize, ]"HaE-`%
!CX WoM
startIndex); OqIXFX"
return ps; VqV [ @[P
} hXth\e\[{`
}, true); jzJTV4&zjs
} mN}szW,
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public List findAllByCriteria(final ws5Ue4g|
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DetachedCriteria detachedCriteria){ WYTqQqQk
return(List) getHibernateTemplate #f) TAA
K&%CeUa
().execute(new HibernateCallback(){ ~qeFSU(
publicObject doInHibernate tF}^
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(Session session)throws HibernateException { FMeBsI9pL
Criteria criteria = p>+9pxx~U
"}qs+
detachedCriteria.getExecutableCriteria(session); G2kU_
return criteria.list(); CA0XcLiFt
} [ ,Go*r
}, true); |mQ Fi\
} $~.YB\3
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public int getCountByCriteria(final i cTpx#|=
N$]er'`
DetachedCriteria detachedCriteria){ 8]&:'
Integer count = (Integer) |A'I!Jm
jW`JThoq
getHibernateTemplate().execute(new HibernateCallback(){ B ??07j
publicObject doInHibernate j8&NscK)
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(Session session)throws HibernateException { WV$CZgL
Criteria criteria = ;C$+8%P4
|{YN3"qN
detachedCriteria.getExecutableCriteria(session); A,DBq9Z+4R
return e9h@G#
s/IsrcfM
criteria.setProjection(Projections.rowCount $!.>)n
'^_u5Y]
()).uniqueResult(); Tl2t\z+ps
} )/::i
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}, true); `2s@O>RV
return count.intValue(); F,p0OL.
} 6I@j$edZ
} 43AzNXWF8
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X"r)zCP+t
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用户在web层构造查询条件detachedCriteria,和可选的 [UzD3VPg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *pJGp:{6V?
^)gyKl:E'
PaginationSupport的实例ps。 8mreHa
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ps.getItems()得到已分页好的结果集 Bxm,?=h
ps.getIndexes()得到分页索引的数组 2P"9m
ps.getTotalCount()得到总结果数 <(lA
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ps.getStartIndex()当前分页索引 =WY'n
l'
ps.getNextIndex()下一页索引 1z-.e$&z
ps.getPreviousIndex()上一页索引 o?Hfxp0}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 13!@LbC
}~I!'J#)
,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 luf5-XT
g^]Iw~T6$
一下代码重构了。 XX~vg>3_
':wf%_Iw
我把原本我的做法也提供出来供大家讨论吧: c
3QgX4vq
VyxYv-$Y
首先,为了实现分页查询,我封装了一个Page类: 1XSnnkJm
java代码: s7 "xDDV
x"12$ 79=
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/*Created on 2005-4-14*/ sW]^YT>?
package org.flyware.util.page; -XV,r<''
q`<:CfCt
/** P9cx&Hk9
* @author Joa 2^WJ1: A
* d+JK")$9C
*/ o]e,5]
publicclass Page { lnZ{Ryo(
5.~Je6K U
/** imply if the page has previous page */ jfxNV2[
privateboolean hasPrePage; wX"hUu
i?6&4
/** imply if the page has next page */ =:WZV8@%
privateboolean hasNextPage; 8v"rM
>[
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/** the number of every page */ EU?qLj':
privateint everyPage; {[oNUzcd
ff#7}9_mh
/** the total page number */ \Z]+j@9
privateint totalPage; X8|H5Y:
pr0X7 #_E5
/** the number of current page */ .{1$;K @
privateint currentPage; H`JFXMa<
b' o]Y
/** the begin index of the records by the current xo"GNFh!
cfLLFPhv)
query */ XNYA\%:5S
privateint beginIndex; Hy.u6Jt*/
A5XMA|2_
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/** The default constructor */ }\"EI<$s
public Page(){ 3Zb%-_%j
,"%C.9a
} Z,).)y#B
Ma^jy.
/** construct the page by everyPage _\WR3Q!V
* @param everyPage Dh
I{&$O/
* */ .G8`Ut Z
public Page(int everyPage){ a1cX+{W
this.everyPage = everyPage; |`T(:ZKXZ2
} CY1WT
+Iyyk02V
/** The whole constructor */ R}&?9tVRR
public Page(boolean hasPrePage, boolean hasNextPage, HGQ</5Z
sfM"!{7
9p{4-]
int everyPage, int totalPage, #t+?eye~
int currentPage, int beginIndex){ :5t4KcQ
this.hasPrePage = hasPrePage; -/Q5?0z
this.hasNextPage = hasNextPage; pHeG{<^
this.everyPage = everyPage; F5o8@ Ib]:
this.totalPage = totalPage; L<F8+a7i
this.currentPage = currentPage; E'AR.!
this.beginIndex = beginIndex; 7H6Ts8^S
}
\]ib%,:YU
2.q Zs8&
/** hY"eGaoF"
* @return Ni_H1G
* Returns the beginIndex. @ st>#]i4
*/ [?]N
GTr#
publicint getBeginIndex(){ 7H7
Xbi@
return beginIndex; 6$`< Y?
} _{*} )&!M
ZbFD |~[ V
/** 'oa.-g 5
* @param beginIndex o=m5AUe?J
* The beginIndex to set. 7)rQf{q7
*/ {?qfH>oFA
publicvoid setBeginIndex(int beginIndex){ }a]`"_i;[
this.beginIndex = beginIndex;
|Xso}Y{
} /vQ)$;xf#
V}E['fzBFV
/** o0H^J,6gV
* @return `Y&`2WZ ~
* Returns the currentPage. $S6(V}yh
*/ Rh'z;Gyr
publicint getCurrentPage(){ >q}3#TvP@
return currentPage; 0Wr<l%M)+
} ~;"eNg{T
(}A$4?
/** ,1]UOQ>AP
* @param currentPage '}OdF*L
* The currentPage to set. W{,fpm
*/ Hv/C40uM-
publicvoid setCurrentPage(int currentPage){ eR!#1ar
this.currentPage = currentPage; JYdb^j2c
} FnGKt\
odP<S.
/** o@Ye_aM~?Y
* @return 1[egCC\Mo_
* Returns the everyPage. dwA"QVp{
*/ ,ri&zbB
publicint getEveryPage(){ RD`|Z~:q:K
return everyPage; )vtbA=RH?
} i~!g9o(
yFE0a"0y
/** </I%VHP,[f
* @param everyPage > X~\(|EM
* The everyPage to set. uLdHE5vr
*/ 5wK==hZ
publicvoid setEveryPage(int everyPage){ vl (``5{
this.everyPage = everyPage; zteu{0
} ]3,'U(!+
d6i}xnmC
/** EjPR+m
* @return ][
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* Returns the hasNextPage. S>lP?2J
*/ *l7 `C)
publicboolean getHasNextPage(){ P]+B}))
return hasNextPage; X@~/.H5
} pSx5ume95"
lxn/97rA
/** 1hbQ30
* @param hasNextPage a~2Jf @I3
* The hasNextPage to set. 4 H 6t" X
*/ h,[L6-n
publicvoid setHasNextPage(boolean hasNextPage){ z %}"=
this.hasNextPage = hasNextPage; |!o C7!+0^
} PMQTcQ^
g`y9UYeh
/** <@J$hs9s
* @return V9[_aP;
* Returns the hasPrePage. jOhAXe;~X{
*/ `
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publicboolean getHasPrePage(){ )!(gS,
return hasPrePage; ra~=i|s
} 4"?`p;{Z
Lg\3DzM
/** w1<pQ[A
* @param hasPrePage <:-4GJH=
* The hasPrePage to set. )Kx.v'
*/ 8GkWo8rPk
publicvoid setHasPrePage(boolean hasPrePage){ {aE[h[=r
this.hasPrePage = hasPrePage; u6C_*i{2
} fw %p_Cm
C:1(<1K
/** a`Bp^(f}
* @return Returns the totalPage. L,zx\cj?z
* or-k~1D
*/ $HwF:L)*
publicint getTotalPage(){ ]ZLF=
return totalPage; O72g'qFPE
} +v/y{8Fu
DN^+"_:TB
/** =p|IWn{P
* @param totalPage 3[#^$_96b
* The totalPage to set. :[a*I6/^
*/ \d:Q%S
publicvoid setTotalPage(int totalPage){ .#y#u={{l
this.totalPage = totalPage; C
b'|
} 1F.._5_"]
05F/&+V
} c:Czu
gV)/lDEM5
B1X&O d
%)i&|AV"
m03dL^(
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 aPJTH0u
zd_N' :6
个PageUtil,负责对Page对象进行构造: Ry[7PLn]
java代码: #>yOp *
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i~x]!!
/*Created on 2005-4-14*/ 6$#,$a O
package org.flyware.util.page; Kmx4bp4
5kqI
import org.apache.commons.logging.Log; G5hRx@vfrL
import org.apache.commons.logging.LogFactory; `K VSYC
@zGF9O<3,@
/** ~{DJ,(N"n
* @author Joa {"jtR<{)
* tnpEfi-
*/ IV~)BW leT
publicclass PageUtil { C32*RNG?U
f)vnm*&-
privatestaticfinal Log logger = LogFactory.getLog xS,F
DPA
#Q2s3"X[
(PageUtil.class); .LAB8bg
i:Y5aZc/Ds
/** t7-r YY(
* Use the origin page to create a new page ~_BjcY
* @param page 8Z}%,G*n
* @param totalRecords 3]S_w[Q4
* @return / 8O=3
*/ )h ,v(Rxa
publicstatic Page createPage(Page page, int OGEe8Z9Jt
<uU<qO;6
totalRecords){ ="G2I\
return createPage(page.getEveryPage(), 7j|CWurvq
i&(1<S>P
page.getCurrentPage(), totalRecords); L0VZ>!*o
} H8g6ZCU~
.Z]hS7t
/** ;u`8pF!_eE
* the basic page utils not including exception !,$K;L
Bor_(eL^
handler .{eMN[ n@
* @param everyPage ]@y%j'e
* @param currentPage 3L2NenJB
* @param totalRecords r5[pT(XT]
* @return page ftmPdha%+
*/ bOU"s>?
publicstatic Page createPage(int everyPage, int Sa)sDf1+`
aid1eF
currentPage, int totalRecords){ AyUw
everyPage = getEveryPage(everyPage); NPv.7,
currentPage = getCurrentPage(currentPage); w\[l4|g`
int beginIndex = getBeginIndex(everyPage, ?9?A)?O<j~
7oZ Pb
currentPage); z\FBN=54z
int totalPage = getTotalPage(everyPage, 4'3;{k$z
{1=|H$wKg
totalRecords); %4`
U' j
boolean hasNextPage = hasNextPage(currentPage, O\uIIuy
{tYY
_BI<
totalPage); $S>bcsAy
boolean hasPrePage = hasPrePage(currentPage); ;k0Jl0[}
.~
uKr^%
returnnew Page(hasPrePage, hasNextPage, (z;lNl(*C
everyPage, totalPage, R68:=E4
currentPage, W3ms8=z
s;Bh69
beginIndex); ]' n4e*
} YeT{<9p
K%`]HW@I{
privatestaticint getEveryPage(int everyPage){ h+Lpj^<2a
return everyPage == 0 ? 10 : everyPage; {tOf0W|
} Px-VRANZt
34CcZEQQ
privatestaticint getCurrentPage(int currentPage){ 7f3,czW
return currentPage == 0 ? 1 : currentPage; 4n.JRR&;
} Kt qOA[6
iM7^
privatestaticint getBeginIndex(int everyPage, int t+d7{&B
|d~'X%b%
currentPage){ ho6hjhS|u
return(currentPage - 1) * everyPage; QSzht$8
} 3st?6?7|
A*:|d~
privatestaticint getTotalPage(int everyPage, int ;`xCfOY(
e[Vk+Te7
totalRecords){ gT+wn-3
int totalPage = 0; 0datzEns`
"{+2Q
if(totalRecords % everyPage == 0) y(iq
totalPage = totalRecords / everyPage; ->OVNmCB`+
else nT01B1/<]
totalPage = totalRecords / everyPage + 1 ; %hmRh~/&
&=S:I!9;;
return totalPage; `, ]ui*
} 1D)0\#><
hMz)l\0
privatestaticboolean hasPrePage(int currentPage){ &2.DZ),L
return currentPage == 1 ? false : true; y4@gw.pt
} IP{$lC
>h:'Z*9
privatestaticboolean hasNextPage(int currentPage, ^uG^>Om*
]Ue
aXwaU
int totalPage){ IDf\!QGx
return currentPage == totalPage || totalPage == l -nH
9%SC#V'
0 ? false : true; 569p/?
} `<~=6H
~}{_/8'5
PP\ bDEPy
} -Op^3WWyY
jPo,mz&^
ZXo;E
~s-gnp
tBJ4lb
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。 RcJtVOrd
a {x3FQ
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 ?zC{T*a
,)dlL tUm
做法如下: /zXOtaG
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 nC[aEZ7
/9gn)q2f(
的信息,和一个结果集List: 8PVjNS/
java代码: \}4*}Lr
\ `z%5/@f;
9MO=f^f-
/*Created on 2005-6-13*/ )\D{5j
package com.adt.bo; 2[(~_VJ
WK?5`|1l:x
import java.util.List; 3O-vO=D
xR
kw+
import org.flyware.util.page.Page; j
`!Ge
nhMxw@ Z\
/** xDl;
tFI
* @author Joa &uc`w{,Zs
*/ N.q*jY=X|
publicclass Result { k18v{)i~
JF~9efWe>
private Page page; 6jBi?>[I
o
o'7
private List content; |/xx**?
uh.;Jj;
/** U/AiI;Ne
* The default constructor 'ZI8nMY
*/ _x""-X~OL
public Result(){ sG_/E-%5'
super(); EN[T3 Y
} Ua:@,};
}.'rhR+
/** %x{kd8>u!
* The constructor using fields KiI+ V;o
* <"K*O9nst
* @param page z7sDaZL?_
* @param content z k}AGw
*/ j%y{d(Q4
public Result(Page page, List content){ g"|>^90
this.page = page; "@hd\w{.
this.content = content; rOE:
ap|KL
} ff R%@
6@8t>"}
/** O<V 4j,
* @return Returns the content. %1jcY0zEQ
*/ >P@VD"U
publicList getContent(){ T^`; wD
return content; [PUu9rz#
} lqMr@
:t
6i+,/vr
/** (57!{[J
* @return Returns the page. o<3$|`S&
*/ .1;UEb|T
public Page getPage(){ ;>5`Y8s6
return page;
LFW`ISY{
} N%Ta.`r
d,l?{Ln
/** *5k40?w
* @param content *-5N0K<kQ
* The content to set. Q0K$ZWM`7
*/ .?QYqGcG
public void setContent(List content){ N2'aC}
I
this.content = content; %>=6v}f,+
} 8Vj'&UY
7p2xst
/** I_z(ft.
* @param page TbNH{w|p
* The page to set. MaHP):~
*/ MomHSv Q\
publicvoid setPage(Page page){ 7p Y :.iVO
this.page = page; hPNMp@Nm6
} #I453
} n }A!aC
Mhti
300w\9fn&
4L8hn4F
R^/SBrWve
2. 编写业务逻辑接口,并实现它(UserManager, 0stc$~~v
HrsG^x
UserManagerImpl) 4RtAwB
java代码: 7LrmI~P
b \`S[
rq8 d}wj
/*Created on 2005-7-15*/ lcm[l
package com.adt.service; ^O+ (eA7E
[F-GaaM
import net.sf.hibernate.HibernateException; ;TWLo_
3rKJ<(-2/
import org.flyware.util.page.Page; ]'(D*4
%2zmc%]r
import com.adt.bo.Result; &LAXNk2
=8?Kn@nMN
/** zX&SnT1~
* @author Joa -g2l-N{&
*/ \_8wU'7
publicinterface UserManager { xxu
]1<GZ`
public Result listUser(Page page)throws v}Ju2 }IK
rjK`t_(=
HibernateException; pCh v;
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} s b;q)Rh
\$wkr
P7.bn
&R%'s1]o
,?|$D Y+=
java代码: OA[e}Vn
]c7X~y
MqAi}z%
/*Created on 2005-7-15*/ vW=L{8zu
package com.adt.service.impl; 2Ckx.m &
HTOr
import java.util.List; m<-ShRr*b
I}
jgz
import net.sf.hibernate.HibernateException; 3@gsKtA&H4
Ck
Nl;g l
import org.flyware.util.page.Page; }<0N)dpT
import org.flyware.util.page.PageUtil; A<X?1$
:h{uZ,#Gi
import com.adt.bo.Result; rKrHd
import com.adt.dao.UserDAO; f
5v&4
import com.adt.exception.ObjectNotFoundException; k9;^|Cm
k
import com.adt.service.UserManager; c;$4}U4
aZWj52
/** cQK-Euum
* @author Joa _VKI@
*/ CP~ZIIip"
publicclass UserManagerImpl implements UserManager { HYfGu1j?X
{p84fR1P
private UserDAO userDAO; @vt.Db
9RJF
/** h)HEexyRg
* @param userDAO The userDAO to set. Kgu8E:nL
*/ H&)}Z6C"
publicvoid setUserDAO(UserDAO userDAO){ -^xbd_'
this.userDAO = userDAO; }xk(aM_
} kyJbV[o<#
oBkhb
/* (non-Javadoc) sE pI)9
* @see com.adt.service.UserManager#listUser .$18%jH#
q<dG}aj
(org.flyware.util.page.Page) *5%vU|9b
*/ nF,F#V8l
public Result listUser(Page page)throws $eYL|?P50h
KC6Cg?y^
HibernateException, ObjectNotFoundException { lvO6&sF1
int totalRecords = userDAO.getUserCount(); e7RgA1
if(totalRecords == 0) ITn%
throw new ObjectNotFoundException K oJ=0jM#
ec&/a2M
("userNotExist"); $a M5jH<
page = PageUtil.createPage(page, totalRecords); 4E39]vb
List users = userDAO.getUserByPage(page); :RIz6Tz
returnnew Result(page, users);
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}
p{g4`o
??,[-Oi
} C`[<6>&y
8:,($a/KF
kFn/dQ4|
V*giF`gq
s?w2^<P
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 1xB}Ed*k
[eX]x
询,接下来编写UserDAO的代码: 94"+l@K
3. UserDAO 和 UserDAOImpl: .AfZ5s]/F
java代码: 7Y5 r3a}%
[.gk{> #
vd%g'fTy9
/*Created on 2005-7-15*/ n)e2?
package com.adt.dao; LhJUoX
srGOIK.
import java.util.List; (pxH<k=Ah
.kT]^rv
;
import org.flyware.util.page.Page; yLnQ9BXB&
t6DSZ^Zq
import net.sf.hibernate.HibernateException; 3uLG$`N
q+?<cjVg
/** VdlT+'HF
* @author Joa DB/~Z
*/ mmTpF]t
?`
publicinterface UserDAO extends BaseDAO { 4q}+8F`0F
@J[@Pu O
publicList getUserByName(String name)throws X1Yw=t~a
ldA_mj{
HibernateException; hd3
x-BU$bx5
publicint getUserCount()throws HibernateException; I/O3OD
FK _ ZE>
publicList getUserByPage(Page page)throws *w+'I*QSt~
+\eJxyO
HibernateException; M3tl4%j
a:BW*Hy{\
} )1s5vNVa
)?F&`+
e\%,\uV}
VOEV[?>ss
K./qu^+k
java代码: ;TAj;Tf]H
|N)Ik8
$*#a;w7\C
/*Created on 2005-7-15*/ %HUex
6!
package com.adt.dao.impl; aAg Qv*
Ykxk`SJ
import java.util.List; &jE\D^>ko
I!lDKS,b
import org.flyware.util.page.Page; Cv**iW
g)Lf^
import net.sf.hibernate.HibernateException; BEDkyz;:
import net.sf.hibernate.Query; yf&g\ke
O^L]2BVC
import com.adt.dao.UserDAO; i2=- su
W/Dd7G#IC
/** L@N%S Sf
* @author Joa &6eo;8
`U
*/ 2W,9HSu8
public class UserDAOImpl extends BaseDAOHibernateImpl vV,TT%J8D
y]db]pP5
implements UserDAO { FZ"n6hWA
l_g$6\&|
/* (non-Javadoc) q$:1Xkl
* @see com.adt.dao.UserDAO#getUserByName RkYdK$|K
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(java.lang.String) `"5Ub,~
*/ +A}t_u3<
publicList getUserByName(String name)throws fap`;AuwK
r w?wi}}gn
HibernateException { 6jq*lnA%
String querySentence = "FROM user in class aU!}j'5Q
^ZwZze:2
com.adt.po.User WHERE user.name=:name"; I\l&'Q^0@
Query query = getSession().createQuery V*vQNPey
-S sgW
(querySentence);
r h*F
query.setParameter("name", name); Qi18q|l8v
return query.list(); ]
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} 7^eyO&4z
JipNI8\r
/* (non-Javadoc) %3z[;&*3O
* @see com.adt.dao.UserDAO#getUserCount() ^ja]e%w#
*/ yXNr[7
publicint getUserCount()throws HibernateException { Q]WBH_j
int count = 0; :?M_U;;z2+
String querySentence = "SELECT count(*) FROM DQG%`-J
GcV/_Y
user in class com.adt.po.User"; btW#ebm
Query query = getSession().createQuery PmuG(qg
20c5U%
(querySentence); @:N8V[*u
count = ((Integer)query.iterate().next PCT&d)}
Mu3G/|t(
()).intValue(); , $ 7-SN
return count; 'O<b'}-A
} q[s,q3n~
\{h_i
FU!
/* (non-Javadoc) Zbczbnj
* @see com.adt.dao.UserDAO#getUserByPage &g:( I
kWr1>})'
(org.flyware.util.page.Page) U0&myj 8L
*/ _Ewh:IM-
publicList getUserByPage(Page page)throws %' DOFiU
R"cQyG4
HibernateException { iOiFkka
String querySentence = "FROM user in class 6n9/`D!
kV'zAF
v
com.adt.po.User"; t&?jJ7 (&8
Query query = getSession().createQuery "f91YX_)
Fb,*;M1'
(querySentence); #}7T$Va
query.setFirstResult(page.getBeginIndex()) HPtMp#`T
.setMaxResults(page.getEveryPage()); W@R7CQE@
return query.list(); Rw+r1vW:A
} )tlj{ 7p
iv*RE9?^
} pwo$qs(p
"6U0
!.ro@
d"|_NG` vr
PQaTS*0SXJ
dz^HN`AlzC
至此,一个完整的分页程序完成。前台的只需要调用 }qWnn>h9xv
KI9Pw]]{-
userManager.listUser(page)即可得到一个Page对象和结果集对象 9PB%v.t5y
9vRLM*9|
的综合体,而传入的参数page对象则可以由前台传入,如果用 t0e6iof^o
VY6G{f
webwork,甚至可以直接在配置文件中指定。 [UwQi!^-O
u62H+'k}F
下面给出一个webwork调用示例: -Q? i16pM
java代码: [n"eD4 )K|
Xt$qjtVM
@qNY"c%HV
/*Created on 2005-6-17*/ wDvu2iC=
package com.adt.action.user; u!X~!h-6~
+$C9@CZM9
import java.util.List; %R GZu\p
o*K7(yUL4
import org.apache.commons.logging.Log; aE0R{yup Z
import org.apache.commons.logging.LogFactory; m*
3ipI{h
import org.flyware.util.page.Page; ?d Jd7+A
S)hDsf.I
import com.adt.bo.Result; 6FDj :~
import com.adt.service.UserService; `:&RB4Z
import com.opensymphony.xwork.Action; N82 6xvA
lf"w/pb'
/** EjfQF C
* @author Joa EV6R[2kl
*/ B Ewa QvQ!
publicclass ListUser implementsAction{ 7;Ze>"W>
+3o
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privatestaticfinal Log logger = LogFactory.getLog 2/3yW.C
>/-H!jUF]
(ListUser.class); $}vk+.!*1
tav@a)
private UserService userService; Q0xGd(\
JV_`E_!
private Page page; O
_9r-Zt^
"rMfe>;FJ
privateList users; p&I>xu8fl
A.b^?k%I
/* )j2#5`?"j
* (non-Javadoc) B
W*8
* & %/p;::A
* @see com.opensymphony.xwork.Action#execute() K~#?Y,}O
*/ e6p3!)@P1
publicString execute()throwsException{ sqhMnDn[
Result result = userService.listUser(page); M"*NV(".g
page = result.getPage(); d'(n/9K
users = result.getContent(); h] ho? K
return SUCCESS; qt9jZtx
} =|J*9z;
c&PsT4Wh
/** )q{qWobS0
* @return Returns the page. +mjwX?yF
*/ A\?t^T
public Page getPage(){ T"99m^y
return page; Tu-lc)
} g7323m1=
0j8fU7~6S
/** +788aK,{#
* @return Returns the users. ~Bl,_?CBr
*/ g@ J F
publicList getUsers(){ dF `7]
return users; ,q%X`F
rc
} 0WzoI2Q
8b0j rt
/** ?5't1219
* @param page d"5_x]Z;
* The page to set.
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*/ Ch{6=k bK
publicvoid setPage(Page page){ Lu^uY7
?}
this.page = page; <k[_AlCmsg
} u$tst_y-
gZ&4b'XS,
/** ^0"^
* @param users `IlhLv
* The users to set. +76'(@(1Y
*/ {
1~]}K2
publicvoid setUsers(List users){ 1D[V{)#
this.users = users; 'bRf>=
} G1it
3^*$
iJdJP)!tz6
/** `'|6b5`2j
* @param userService <Z t ]V`-
* The userService to set. bq5ySy{8
*/ (~Bm\ Jn
publicvoid setUserService(UserService userService){ 1<~n2}
this.userService = userService; <mP_K^9c
} j&dCP@G
} ()j)}F#Z`
,X|FyO(p
@[joM*U
Zz (qc5o,F
_*=4xmB.=
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, Ng<ic
-N/n|{+F
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 \RDqW+,
?VxQ&^|
么只需要: g_ep
5#\D
java代码: 7V^j9TC
_"F=4`lJ
ug{sQyLN
<?xml version="1.0"?> |:SV=T:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1c/<2 xO~
e+#Oj
1.0//EN" "http://www.opensymphony.com/xwork/xwork- GZ<@#~1%\
iuqJPW^}
1.0.dtd"> C%z9Q
ZwxEcs+UM
<xwork> .z$UNB(!M
U(+QrC:
<package name="user" extends="webwork- ph)=:*A6&
!1S!)#
interceptors"> Y#): 1C1
})!-
<!-- The default interceptor stack name n9
bp0#K
G~_eBy
--> ;[lLFI
<default-interceptor-ref >g+Y//Z
ej7N5~!,s
name="myDefaultWebStack"/> 6}@T^?
UCmJQJc
<action name="listUser" B4*,]lS?
Ts, U T L
class="com.adt.action.user.ListUser"> 0n X5Vo
<param 6qV1_M#
~K)FuL[*
name="page.everyPage">10</param> 6_8y Q
<result N1E9w:T`
i< imE#
name="success">/user/user_list.jsp</result> #6y fIvap
</action> {?w*n_T.
Ac*)z#H
</package> Grw[h
2fayQY
xD
</xwork> %26HB
w=JF
/ E!6]b/
Z@m5hx&
V/\`:
l YdATM(h
8%; .H-
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 Ozulp(8*
3?gfDJfE
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。 |J-tU)|1vl
B}y#AVSA
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ]We0 RD"+
t
~]'
{[F
$Y$s*h_-/<
nJgN2Z
j$u
我写的一个用于分页的类,用了泛型了,hoho N>s3tGh
\(?d2$0m
java代码: L`:V]p
>)[W7h
3<Z@!ft8
package com.intokr.util; 0aGauG[
HWL? doM
import java.util.List; 0|hOoO]?q&
_=[pW2p
/** D!)h92CIDm
* 用于分页的类<br> P$O@G$n
* 可以用于传递查询的结果也可以用于传送查询的参数<br> =L"I[
* e'v_eD T^
* @version 0.01 /lHs]) ,
* @author cheng <g&GIFE,
*/ 8SiWAOQAL
public class Paginator<E> { 5M>SrZH
privateint count = 0; // 总记录数 oY\;KPz
privateint p = 1; // 页编号 -G1R><8[
privateint num = 20; // 每页的记录数 Uu`}| &@i
privateList<E> results = null; // 结果 !}eq~3
M.$=tuUL
/** 925T#%y
* 结果总数 5}]gL
*/ DM,;W`|6%
publicint getCount(){ *rm[\
return count; |jWA >S
} 2fm6G).m
ZTGsZ}{5
publicvoid setCount(int count){ tQMz1$
this.count = count; I$TD[W
} sWq}/!@&
d)%l-jj9,
/** Me+)2S 9
* 本结果所在的页码,从1开始 /PBK:B
* a5]]AkvA
* @return Returns the pageNo. !$-QWKD4
*/
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publicint getP(){ pL.~z
return p; v`jFWq8I,
} WK SWOSJ
VM3)L>x]/
/** *:chN' <
* if(p<=0) p=1 >LU !Z
* xLbF9ASim
* @param p CS xB)-
*/ MA mjoH
publicvoid setP(int p){ V2 }.X+u&<
if(p <= 0) _2})URU<S
p = 1; ka8=`cn
this.p = p; >BMtR0
} ~c=*Y=)LG
bOlb
/** XOZ@ek)LY
* 每页记录数量 \7(OFT\u:
*/ tgrZs8?
publicint getNum(){ !6+V
return num; /jU4mPb;\D
} - :x6X$=
;4vx+> -
/** ?l
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* if(num<1) num=1 Nu; 9
*/ oFu( J
publicvoid setNum(int num){ ub{Yg5{3S\
if(num < 1) _lOyT$DN
num = 1; %G] W Oq=q
this.num = num; `]2y=f<{X
} x1`Jlzrp,
LC/%AbM
/** C:}"?tri
* 获得总页数 .18MMzdN
*/ ];Bk|xJ/>
publicint getPageNum(){ qS[nf>"
return(count - 1) / num + 1; ,5|@vW2@u
} 8rjiW#
gM
v0[~;u
/** p:4oA<V
* 获得本页的开始编号,为 (p-1)*num+1 \//{\d
*/ Znh<r[p<
publicint getStart(){ #|} EPD9$
return(p - 1) * num + 1; {,o 0N\(
} ,NU`aG-
bO gVCg
/** rge/qUr/^
* @return Returns the results. :LR>U;2
*/ )G|'PXI@,
publicList<E> getResults(){ (DKQHL;
return results; iC<qWq|S_m
} !*-|s}e
vj<JjGP
public void setResults(List<E> results){ NFb<fD[C
this.results = results; 0a's[>-'A
} Dn.%+im-u
E"Y[k8-:2/
public String toString(){ Ivc/g,
StringBuilder buff = new StringBuilder sMWNzt
?xCWg.#l4V
(); #6Fc-ysk:
buff.append("{"); 140_WV?7
buff.append("count:").append(count); ~0gHh
buff.append(",p:").append(p); e:WKb9nT
buff.append(",nump:").append(num); Ne2eBmY}(
buff.append(",results:").append kCU(Hi`Q
:.fm LL
(results); xAAwH@ +
buff.append("}"); 5+iXOs<
return buff.toString(); UJQGwTA W
} ft4(^|~
*Ag,/Cm]
} p#AQXIF0
kR;Hb3hb
QpMi+q
Y