Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 gs 8w/
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 :N^1T6v
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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 bv0B
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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 N+l~r]: &
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分页支持类: X`]-)(UX
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java代码: BDxrS q,H
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package com.javaeye.common.util; ;_K+b,
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import java.util.List; GmtMA|
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publicclass PaginationSupport { 8,YF>O&
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publicfinalstaticint PAGESIZE = 30; &T]+g8 ''
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privateint pageSize = PAGESIZE; zy4AFW
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privateList items; IGT~@);
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privateint totalCount; F}0QocD
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gbj;
privateint[] indexes = newint[0]; *jGB/ y
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privateint startIndex = 0; KoiU\r
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public PaginationSupport(List items, int B P"PUl:
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totalCount){ |`s}PcV
setPageSize(PAGESIZE); 66D<Up'K
setTotalCount(totalCount); wc)[r~On(5
setItems(items); Di9yd
setStartIndex(0); D/V.o}X$
} *)ed( +b
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public PaginationSupport(List items, int hiaj!&+Q
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totalCount, int startIndex){ 0ang~_
setPageSize(PAGESIZE); V-A^9AAPm
setTotalCount(totalCount); qh0)~JL4
setItems(items); &o^ wgmS
setStartIndex(startIndex); /`\-.S9
} vPmP<c)cb
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public PaginationSupport(List items, int dVVeH\o
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totalCount, int pageSize, int startIndex){ oHI~-{m3)
setPageSize(pageSize); XZcsx
setTotalCount(totalCount); uA
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setItems(items); h\'GL(?DBI
setStartIndex(startIndex); Yp 6;Y7^
} ,p1 (0i
& /-@R|
publicList getItems(){ .`Z{ptt>
return items; k}ps-w6:
} }yx{13:[
cLr? B;FS
publicvoid setItems(List items){ <Ml,H%F
this.items = items; T_Z@uZom.
} _I~TpH^1K
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publicint getPageSize(){ ;DC0LJ
return pageSize; au"HIyi?k
} X$/3
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publicvoid setPageSize(int pageSize){
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this.pageSize = pageSize; }S*6+4
} FPaj
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publicint getTotalCount(){ *^Zt5 zk
return totalCount; t8i"f L
} gywI@QD%#
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publicvoid setTotalCount(int totalCount){ hNDhee`%6
if(totalCount > 0){ [.6>%G1C
this.totalCount = totalCount; mI9h| n
int count = totalCount / :m#vvH
wrqdQ}@(
pageSize; &@dMk4BH<
if(totalCount % pageSize > 0) ,Lv}Xku
count++; c::x.B"w
indexes = newint[count]; Lom%eoH)
for(int i = 0; i < count; i++){ nyQFS
indexes = pageSize * b8b-M]P-=
eVU:.fx
i; 6sP;O,UX
} &tWWb`
}else{ JTx}{kVO
this.totalCount = 0; fEVuH]
} 0p2 0Rt
} QMtt:f]?i
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publicint[] getIndexes(){ 'Dat.@j
return indexes; LWVO%@)w
} ^]U2Jd
bx6@FKns}
publicvoid setIndexes(int[] indexes){ 7[D0n7B@
this.indexes = indexes; C{!Czz.N
} ykM#EyN
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publicint getStartIndex(){ _'I9rGlx3
return startIndex; '')G6-c/
} 7y[B[$P
_Fz)2h,3
publicvoid setStartIndex(int startIndex){ Ku&(+e
if(totalCount <= 0) ,1~Zqprn
this.startIndex = 0; +B8Ut{l
elseif(startIndex >= totalCount) 2$\f !6p
this.startIndex = indexes s|,]Nb=z/
ZM|>Va/X
[indexes.length - 1]; b%oma{I=.c
elseif(startIndex < 0) G x,D'H'
this.startIndex = 0; 1c}'o*K_%
else{ nn=JM7e\9
this.startIndex = indexes 1Rczf (,aT
fLD9RZ8_
[startIndex / pageSize]; _eO] awsA
} [w{ZP4d>
} M2s
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publicint getNextIndex(){ Ey6K@@%
int nextIndex = getStartIndex() + %1=W#jz
ux=a9
pageSize; yBl<E$=
if(nextIndex >= totalCount) 8vT:icl
return getStartIndex(); 2sU"p5 j
else }s)Z:6;(,q
return nextIndex; 92SB'T>
} ;JZXSM-3
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publicint getPreviousIndex(){ Q1jyetk~I
int previousIndex = getStartIndex() - s]I],>}RU
F;b|A`M
pageSize; mdZELRu
if(previousIndex < 0) qnA:[H;F
return0; <5X@r#Lz
else ;8T<L[ ^U
return previousIndex; .1pEq~>
} zu^ AkMc
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} "|Pl(HX
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a 6 ]!4
抽象业务类 NNfCJ|
java代码: nuC K7X
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/** uZYeru"w
* Created on 2005-7-12 `773& \PK
*/ z)0VP QMT
package com.javaeye.common.business; c3}}cFe
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import java.io.Serializable; )R|7> 97
import java.util.List; [-CG&l2?L
-0]aOT--
import org.hibernate.Criteria; NRl"!FSD;"
import org.hibernate.HibernateException; zJsoenU
import org.hibernate.Session; r zvX~B6
import org.hibernate.criterion.DetachedCriteria; 2Z97Tq
import org.hibernate.criterion.Projections; $?s^HKF~
import s{IoL_PJP
aQG#bh [
org.springframework.orm.hibernate3.HibernateCallback; srSTQ\l4
import T9$U./69-L
<VBw1|)$@
org.springframework.orm.hibernate3.support.HibernateDaoS : 1{j&$
"/"qg
upport; ;CvGIp&y
4ku /3/6
import com.javaeye.common.util.PaginationSupport; ex=~l O
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public abstract class AbstractManager extends eeDhTw9
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HibernateDaoSupport { SH(kUL5
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privateboolean cacheQueries = false; D#$gdjZ
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privateString queryCacheRegion; UQ8x#(`ak
NV gLq@F
publicvoid setCacheQueries(boolean ~mp$P+M(%p
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cacheQueries){ iWCV(!
this.cacheQueries = cacheQueries; Z-<u?f8{*
} joA+
##5/%#eZ
publicvoid setQueryCacheRegion(String YNXk32@j@e
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queryCacheRegion){ 6a@~;!GlI
this.queryCacheRegion = BNy"YK$
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queryCacheRegion; O<3,n;56Z
} wY95|QS
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publicvoid save(finalObject entity){ 47 RY pd
getHibernateTemplate().save(entity); zb" hy"hKw
} Qx6/QaS?
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publicvoid persist(finalObject entity){ ]/bE${W*]
getHibernateTemplate().save(entity); wgyO%
} V4-=Ni]k
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publicvoid update(finalObject entity){ TH|hrL;:8
getHibernateTemplate().update(entity); e!yw"Cf*
} AH`15k_i
</X"*G't
publicvoid delete(finalObject entity){ $imx-H`|
getHibernateTemplate().delete(entity); c{Kl?0#[
} _E;Y
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publicObject load(finalClass entity, `@M4THt
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finalSerializable id){ ]'Yw#YB
return getHibernateTemplate().load 2X*<Fma3C
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(entity, id); @r ?`:&m0
} kut|A
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publicObject get(finalClass entity, ?a%i|Z7!
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finalSerializable id){ Q.1ohj0)
return getHibernateTemplate().get zl\#n:|
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(entity, id); H1nQ.P]_
} 0vp I#q
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publicList findAll(finalClass entity){ ak>NKK8P
return getHibernateTemplate().find("from 1 =<|h
,*[LnR
" + entity.getName()); Z-|C{1}A
} \DqxS=o;
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publicList findByNamedQuery(finalString p]&Q`oh
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namedQuery){ ?6d4T
return getHibernateTemplate _|ib@Xbin
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().findByNamedQuery(namedQuery); / yi :Q0
} a1SOC=.M;
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publicList findByNamedQuery(finalString query, $0}bi:7
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finalObject parameter){ 'cN#rHPB6
return getHibernateTemplate qJU)d
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().findByNamedQuery(query, parameter); # &83;uys
} sK0VT"7K
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publicList findByNamedQuery(finalString query, g i'agB^
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finalObject[] parameters){ Qiw4'xQm
return getHibernateTemplate q}$=bR1+
9D{).f0
().findByNamedQuery(query, parameters); f9UaAdJ(
} gF6j6
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publicList find(finalString query){ i@5%d!J
return getHibernateTemplate().find /\cu!yiX
]Cn*C{
(query); [IFRwQ^%_O
} ;Ia1L{472m
jHH
publicList find(finalString query, finalObject O/9%"m:i
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parameter){ ]t)M}^w
return getHibernateTemplate().find * g4Cy8$
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(query, parameter); ^YJA\d@
} WWW#s gM%
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public PaginationSupport findPageByCriteria +esNwz_
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(final DetachedCriteria detachedCriteria){ Ln2C#Uf
return findPageByCriteria Dh No +"!z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5`'=Ko,N
} >B /&V|E
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public PaginationSupport findPageByCriteria IXvz&4VD
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(final DetachedCriteria detachedCriteria, finalint ASZ5;N4u
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startIndex){ ef}E.Bl
return findPageByCriteria 3
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(detachedCriteria, PaginationSupport.PAGESIZE, lzs(i2pA
'$h@
startIndex); 0j!ke1C&C
} $Cd ;0gdv
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public PaginationSupport findPageByCriteria -*hb^MvP
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(final DetachedCriteria detachedCriteria, finalint `JWYPsWk
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pageSize, xSDE6]
finalint startIndex){ x*&&?nV Iz
return(PaginationSupport) #VdI{IbW
E)Qh]:<2v
getHibernateTemplate().execute(new HibernateCallback(){ PR@4' r|a
publicObject doInHibernate 7s8<FyFsjd
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(Session session)throws HibernateException { .\~P -{Hd
Criteria criteria = w$lfR,
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detachedCriteria.getExecutableCriteria(session); $wYuH9(
int totalCount = )yNw2+ ~5
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((Integer) criteria.setProjection(Projections.rowCount ~"q,<t
c >
mu)('U
()).uniqueResult()).intValue(); cxD}t'T
criteria.setProjection Md>f
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(null); a|P~LMPM
List items = B2G5hbaA
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criteria.setFirstResult(startIndex).setMaxResults +# RlX3P
cl8_rt
(pageSize).list(); oBj>9I;
PaginationSupport ps = a\&(Ua
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new PaginationSupport(items, totalCount, pageSize, Ztyv@z'/Z
qBBYckS.
startIndex); }^pQbFku
return ps; n-y^7'v
} #'4<> G]
}, true); pcuMGo-#
} yF/< :
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public List findAllByCriteria(final s0)qlm*
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DetachedCriteria detachedCriteria){ O,=Q1*c,&
return(List) getHibernateTemplate =tS[&6/
DO1 JPeIi
().execute(new HibernateCallback(){ xMSNrOc
publicObject doInHibernate yL;o{
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(Session session)throws HibernateException { Q.9Ph
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Criteria criteria = ]@/^_f>D
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detachedCriteria.getExecutableCriteria(session); x0u?*5-t
return criteria.list(); of+phMev
} })zB".
}, true); K=m9H=IX~T
} J-, H6u
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public int getCountByCriteria(final m]0^
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DetachedCriteria detachedCriteria){ piYws<Q
Integer count = (Integer) Bbl)3$`,
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getHibernateTemplate().execute(new HibernateCallback(){ 'YZI>V*
publicObject doInHibernate vZ[$H
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(Session session)throws HibernateException { QN5yBa!Wz
Criteria criteria = Q{qj
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detachedCriteria.getExecutableCriteria(session); P~Te+ -jX}
return *xX(!t'
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criteria.setProjection(Projections.rowCount [GR]!\!%~
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()).uniqueResult(); hl6,#2$
} Y7*(_P3/
}, true); 6(N.T+;]
return count.intValue(); Gd30Be2gd
} ?418*tXd
} C.yY8?|
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用户在web层构造查询条件detachedCriteria,和可选的 a%7"_{s1
1<LC8?wt
startIndex,调用业务bean的相应findByCriteria方法,返回一个 %_B:EMPd
, @%C8Z
PaginationSupport的实例ps。 s{(ehP.Dd
c
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ps.getItems()得到已分页好的结果集 IWjR0
ps.getIndexes()得到分页索引的数组 6}VUD
-}B
ps.getTotalCount()得到总结果数 oupJJDpP
ps.getStartIndex()当前分页索引 =cf{f]N
ps.getNextIndex()下一页索引 LPEjRG,
ps.getPreviousIndex()上一页索引 T&9`?QD
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jd ["eI
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 %B#hb<7}
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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 &mh Ln4^
d^KBIz8$5l
一下代码重构了。 ]s*5[=uc2
3C277nx
我把原本我的做法也提供出来供大家讨论吧: KqN!?anPr
5a=nF9/
首先,为了实现分页查询,我封装了一个Page类: .cw!ls7d
java代码: kRmj"9oA
25x cD1*
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/*Created on 2005-4-14*/ HA$Y1}
package org.flyware.util.page; r#LnDseW
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/** sW;7m[o
* @author Joa rs[?v*R74
* @4;HC=~
*/ _FL<egK
publicclass Page { Q/9a,85
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/** imply if the page has previous page */ /VRUz++K
privateboolean hasPrePage; ^4+r*YvcM
J1.qhy>
/** imply if the page has next page */ *Y8XP8u/
privateboolean hasNextPage; jMK3T
CXBzX:T?#
/** the number of every page */ fucUwf\_
privateint everyPage; {UP'tXah
j._G7z/LJ
/** the total page number */ ;5<P|:^
privateint totalPage; 0r1g$mKb
-Bj.hx*
/** the number of current page */ f.@Xjf
privateint currentPage; BRe{1i 6
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/** the begin index of the records by the current hO#HvW
LRWOBD
query */ 5!<o-{J[(=
privateint beginIndex; #-,g&)`]
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/** The default constructor */ >W'j9+Va
public Page(){ YZ0en1ly
*yrnK3
} y
$:yz;
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/** construct the page by everyPage pP3U,n
* @param everyPage iu+3,]7Fm
* */ !;i*\
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public Page(int everyPage){ USprsaj
this.everyPage = everyPage; FS8S68
} 6{Ks`Af
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/** The whole constructor */ Gi*<~`Gr
public Page(boolean hasPrePage, boolean hasNextPage, P2Onkl
|H:<:*=6c
s,w YlVYf!
int everyPage, int totalPage, 9GThyY
int currentPage, int beginIndex){ 0Su_#".-*
this.hasPrePage = hasPrePage; N3ZiGD
this.hasNextPage = hasNextPage; \4aKLr
this.everyPage = everyPage; Y:wF5pp;
this.totalPage = totalPage; !#. \QU|
this.currentPage = currentPage; sv'
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this.beginIndex = beginIndex; i!L;? `F{
} e|VJ9|;3
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/** d4J<,
* @return tR<L`?4
* Returns the beginIndex. |-n
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*/ e[}],W
publicint getBeginIndex(){ t~ -J %$
return beginIndex; y5_XHi@u~o
} E[UO5X
>&1um5K
/** R3?:\d{
* @param beginIndex )i0 $j)R
* The beginIndex to set. ?NlSeh
*/ :Dayv6g
publicvoid setBeginIndex(int beginIndex){ Ih()/(
this.beginIndex = beginIndex; Yq
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} [.a;L">
R>*g\}9Zh3
/** &
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* @return V/ +Jc(N
* Returns the currentPage. Evkt_vvf
*/ PRwu
publicint getCurrentPage(){ Q3,=~}ZNK
return currentPage; 8[M*
x3
} `dO}L
".E5t@ }?m
/** ywEDy|Wn$~
* @param currentPage QF.3c6O@
* The currentPage to set. ;b1wk^,Hw~
*/ o!utZmk$
publicvoid setCurrentPage(int currentPage){ 6|^0_6_
this.currentPage = currentPage; odpUM@OAW
} |Ytg
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/** C3)|<E
* @return /VO^5Dnb
* Returns the everyPage. *> KHRR<N
*/ gQ>2!Qc a-
publicint getEveryPage(){ tOM(U-7Z&
return everyPage; JpmB;aL#%
} |!Fk2Je,
&n|*uLn
/** ZBJ3 VK
* @param everyPage -w ~(3(
* The everyPage to set. Q&PB]D{
*/ b_=8!Q.:
publicvoid setEveryPage(int everyPage){ 2e.N"eLNt
this.everyPage = everyPage; IA2GUnUhu
} b=1%pX_
O3Uh+gKQ
/** 1ef'7a7e8
* @return w;+ br
* Returns the hasNextPage. AW/wI6[T
*/ (Y2mmd
publicboolean getHasNextPage(){ .T$D^?G!D
return hasNextPage; 13a(FG
} [4XC#OgA
@KA1"Wb_
/** sa9fK Z'q
* @param hasNextPage O:^'x*}
* The hasNextPage to set. j#VIHCzlr
*/ wbi3lH:;
publicvoid setHasNextPage(boolean hasNextPage){ qo_]ZKL44
this.hasNextPage = hasNextPage; e\9g->DUs
} _!!}'fMC
M6Pw/S!
/** 8;#AO8+U7)
* @return [@3SfQ
* Returns the hasPrePage. "OL~ul5
*/ X>t3|h
publicboolean getHasPrePage(){ 9P.(^SD][z
return hasPrePage; Z>2]Xx%
\
} HabzCH
@Tr&`Hi
/** M3(k'q7&:
* @param hasPrePage T4r5s
* The hasPrePage to set. NR4Jn?l{
*/ 6^E`Sa!s
publicvoid setHasPrePage(boolean hasPrePage){ o@/xPo|
this.hasPrePage = hasPrePage; w<t,j~ Pr#
} qVBL>9O*.
*Hs*,}MS
/** %8w9E=
* @return Returns the totalPage. 3wC
R|ab}
* M&y5AB0
*/ 2*u.3,aW
publicint getTotalPage(){ hD
q2-X}
return totalPage; -eml
} .X'<
D*
}fA;7GW+9
/** ?z=\Ye5x
* @param totalPage U=cWmH
* The totalPage to set. 3SNL5
*/ a2yE:16o6
publicvoid setTotalPage(int totalPage){ eN/G i<
this.totalPage = totalPage; OVR?*"N_
} 73
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-@M3Dwsi3
} >uy%-aXiVa
P`TIaP9%E
+xj "hX>3
mp\%M
1<
c+2%rh1
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 %idk@~H Cg
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个PageUtil,负责对Page对象进行构造: hz\WZ^
java代码: /\E [
t1ze-Ht;
T?npQA07=
/*Created on 2005-4-14*/ /IR#A%U
package org.flyware.util.page; +\`rmI
_%Z P{5D>
import org.apache.commons.logging.Log; V1utUGJV
import org.apache.commons.logging.LogFactory; 2dbRE:v5
6I |A-h
/** J%Mnjk^_\S
* @author Joa B~TN/sd
* @6&JR<g*t
*/ ;h~er6&
publicclass PageUtil { V1<`%=%_W
r]LCvsVa
privatestaticfinal Log logger = LogFactory.getLog %8FN0
ut&/\k=N
(PageUtil.class); mhzYz;}
"&QH6B1U6H
/** c2<,|D|
* Use the origin page to create a new page k^An97J
* @param page saW!9HQj
* @param totalRecords SW9fE:v
* @return ?)i1b\4Go
*/ it1/3y
=]
publicstatic Page createPage(Page page, int {1~T]5
Do*n#=
totalRecords){ \##5O7/1
return createPage(page.getEveryPage(), &[j]Bp?
*YvRNHP
page.getCurrentPage(), totalRecords); pn\V+Rg'
} n%$ &=-Fk
[ee30ELn
/** mX\
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* the basic page utils not including exception B9M>e'H%<
nPA@h
handler ]b}B2F'n
* @param everyPage &erm`Ho
* @param currentPage DDw''
* @param totalRecords (-"`,8K 2}
* @return page YBjdp=als
*/ tu}>:mk
publicstatic Page createPage(int everyPage, int Rs7|}Dl}
!buz<h
currentPage, int totalRecords){ N.hzKq][
everyPage = getEveryPage(everyPage); W3JF5*
currentPage = getCurrentPage(currentPage); {exrwnIZj
int beginIndex = getBeginIndex(everyPage, *<