Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 OnNWci|7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 (=v :@\r
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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 @ ;%+Ms
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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 nXgnlb=
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分页支持类: 'j^A87\M_
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java代码: uFseO9F.2
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package com.javaeye.common.util; gyqM&5b
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import java.util.List; kA`Z#yu
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publicclass PaginationSupport { V$y6=Q<c
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@
publicfinalstaticint PAGESIZE = 30; v-zi ,]W
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privateint pageSize = PAGESIZE; P`/;3u/P
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privateList items; ?LJDBN
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privateint totalCount; ,EkzBVgo
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privateint[] indexes = newint[0]; S6k
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privateint startIndex = 0; gZa/?[+
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public PaginationSupport(List items, int NSQ}:m
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totalCount){ iD*%' #u
setPageSize(PAGESIZE); l;*/F`>c
setTotalCount(totalCount); PI
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setItems(items); $]V,H"
setStartIndex(0); PUt\^ke
} C$"N)6%q
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public PaginationSupport(List items, int 1J`<'{*
#6t 4 vJ1
totalCount, int startIndex){ 1u?h4wC
setPageSize(PAGESIZE); #w%d
setTotalCount(totalCount); )7$1Da|.
setItems(items); @DiXe[kI
setStartIndex(startIndex); J1i{n7f=@
} t)#8r,9c
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public PaginationSupport(List items, int [I*)H7pt}
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totalCount, int pageSize, int startIndex){ gMN>`Z`fV
setPageSize(pageSize); Rm@#GP`
setTotalCount(totalCount); 26SXuFJ@
setItems(items); $w,?%i97
setStartIndex(startIndex); 4Zz%vY
} C`G+b{o
L]wWJL
publicList getItems(){ 9((BOq
return items; ~m/nV81
} 9v\x&h
vY 0EffZ
publicvoid setItems(List items){ 0P{^aSxTP
this.items = items; U2v;[ >=]
} noSkKqP
_&(\>{pm
publicint getPageSize(){ xwuGJ
return pageSize; -cgLEl1 J
} o,-p[1b
qPI\Y3ZU
publicvoid setPageSize(int pageSize){ s9[?{}gd
this.pageSize = pageSize; R07]{
} <z'Pj7c[
sj9j47y
publicint getTotalCount(){ FEC`dSTI
return totalCount; %G'{G
} csh@C
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publicvoid setTotalCount(int totalCount){ z3n273W>6
if(totalCount > 0){ hgYi ,e
this.totalCount = totalCount; 0V RV.Ml
int count = totalCount / jHPkfwfAF
ro& /
pageSize; a+HGlj 2>
if(totalCount % pageSize > 0) [Rj_p&'
count++; ^sF/-/ {?U
indexes = newint[count]; -_*ux!
for(int i = 0; i < count; i++){ ^}w@&Bje
indexes = pageSize * d4ga6N3'
}3825
i; "[wkjNf%
} DpRGPs
}else{ 5T*Uq>x0
this.totalCount = 0; OLH[F
} 3_DwqZ 'O
} 8O[br@h:5
1>c^-"#e^
publicint[] getIndexes(){ #QUQC2P(~
return indexes; #&k`-@b5|
} e/7rr~"|
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publicvoid setIndexes(int[] indexes){ XRl!~Y|
this.indexes = indexes; 9QXBz=Fnf
} 0hNgr'
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publicint getStartIndex(){ BvnNAi
return startIndex; ;L*Ku'6Mt
} +$uQ_ve
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publicvoid setStartIndex(int startIndex){ _J,lF-,
if(totalCount <= 0) #\zC|%2+z
this.startIndex = 0; }'KHF0
elseif(startIndex >= totalCount)
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this.startIndex = indexes #+"1">l
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[indexes.length - 1]; o?{-K-'B$
elseif(startIndex < 0) [g/ &%n0^
this.startIndex = 0; i5*BZv>e
else{ B>;`$-
this.startIndex = indexes +s j2C
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[startIndex / pageSize]; ykS-5E`
} .A Dik}o
} *^3&Y@
qo*%S
publicint getNextIndex(){ ;hV-*;>
int nextIndex = getStartIndex() + ,I2x&Ys&.
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pageSize; Hk 0RT%PK
if(nextIndex >= totalCount) {3* Ne /
return getStartIndex(); 8{-
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else <WiyM[ep
return nextIndex; D7lRZb
} TWeup6k
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publicint getPreviousIndex(){ O>@ChQF
int previousIndex = getStartIndex() -
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vNDf1B5z
pageSize; oHPh2b0
if(previousIndex < 0) Yn_v'Os2
return0; jtv<{7a
else X:>,3[hx|
return previousIndex; 1YtbV3
} f
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} J$^"cCMr
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抽象业务类 adn2&7H
java代码: `'E(L&
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/** "oT&KW
* Created on 2005-7-12 mVd%sWD
*/ K2qKkV@
package com.javaeye.common.business; 8b:GyC5L
n`X}&(O
import java.io.Serializable; `]I p`_{
import java.util.List; r>lo@e0G
c$8M}q:X
import org.hibernate.Criteria; *5KDu$'(e
import org.hibernate.HibernateException; Rd;^ fBx
import org.hibernate.Session; 'j9x(T1M1
import org.hibernate.criterion.DetachedCriteria; 8\S$iGd
import org.hibernate.criterion.Projections; s^"*]9B"
import 8dLK5"_3
-4v2]
org.springframework.orm.hibernate3.HibernateCallback; a|-ozBFR
import no,b_0@N
{Rz(0oD\
org.springframework.orm.hibernate3.support.HibernateDaoS O?f?{Jsx
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upport; YS bS.tq
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import com.javaeye.common.util.PaginationSupport; pG^>y0
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public abstract class AbstractManager extends QKI g5I-
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HibernateDaoSupport { >ra)4huZ
gs(ZJO1 /L
privateboolean cacheQueries = false; 6J<R;g23R]
*o=[p2d"X
privateString queryCacheRegion; &9EcgazV
#'5{
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publicvoid setCacheQueries(boolean ODxCD%L
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cacheQueries){ (z:qj/|
this.cacheQueries = cacheQueries; wln"g,ct
} 1b<[/g9
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publicvoid setQueryCacheRegion(String b/d1(B@
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queryCacheRegion){ l^2m7 7)
this.queryCacheRegion = v+~O\v5Q
"I
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queryCacheRegion; x~E\zw
} *{(tg~2'(
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publicvoid save(finalObject entity){ 0*,]`A=
getHibernateTemplate().save(entity); $"g'C8
} M7=|N:/_
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publicvoid persist(finalObject entity){ ;)Sf|
getHibernateTemplate().save(entity); #s{EIj~YR_
} K(AZD&D
Z3f}'vr
publicvoid update(finalObject entity){ H`4KhdqR
getHibernateTemplate().update(entity); riQ0'-p
} {$I1(DYN
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publicvoid delete(finalObject entity){ qS?^(Vt|R
getHibernateTemplate().delete(entity); 5nXmaj
} t4UL|fI
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publicObject load(finalClass entity, 8M,$|\U
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finalSerializable id){
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return getHibernateTemplate().load yeLd,M/I
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(entity, id); #i=m%>zjN
} i)(-Ad_
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publicObject get(finalClass entity, =vsvx{o?
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finalSerializable id){ _QneaPm%
return getHibernateTemplate().get q}C;~nMD
!$p E=~1C
(entity, id); %zN~%mJG
} A]MX^eY
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publicList findAll(finalClass entity){ sj&1I.@,>
return getHibernateTemplate().find("from z8j7K'vV1
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" + entity.getName()); P"|-)d
} |Y30B,=M
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publicList findByNamedQuery(finalString !1#=j;N`
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namedQuery){ .ZupsS9l
return getHibernateTemplate Hq|{Nt%Q
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().findByNamedQuery(namedQuery); L0*f(H
} Qp-P[Tc
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publicList findByNamedQuery(finalString query, 7
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finalObject parameter){ \CBL[X5tr
return getHibernateTemplate S<g~VK!Tt
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().findByNamedQuery(query, parameter); g6@^n$Y
} *t`=1Ioj
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publicList findByNamedQuery(finalString query, Ej<`HbJ'Q
\)cbg#v
finalObject[] parameters){ {6mFI1;q
return getHibernateTemplate >gDKkeLD
dB8 e
().findByNamedQuery(query, parameters); @&GY5<&b
} G@U}4'V9
91UC>]}H
publicList find(finalString query){ $\L=RU!c}
return getHibernateTemplate().find j07b!j:"\}
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(query); EME}G42KN
} Y]Zp[!
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publicList find(finalString query, finalObject bQHJ}aCi
sqO$ka{
parameter){ ,vB nr_D#
return getHibernateTemplate().find 8-9<r
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(query, parameter); GmZ2a-M
} :q$.=?X3
%1rN6A!%
public PaginationSupport findPageByCriteria ,qIut|C*
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(final DetachedCriteria detachedCriteria){ .#LHj}u
return findPageByCriteria A",R2d
Ci?RuZ"
(detachedCriteria, PaginationSupport.PAGESIZE, 0); " t,ZO
} ,D' bIk
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public PaginationSupport findPageByCriteria 9
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(final DetachedCriteria detachedCriteria, finalint [6%y RQ_
?+L7Bd(EF%
startIndex){ [jTZxH<
return findPageByCriteria )Mh5q&ow
{"_V,HmEF+
(detachedCriteria, PaginationSupport.PAGESIZE, Is!+`[ma
7TA&u'
startIndex); ckbD/+
} ,S1'SCwVdJ
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public PaginationSupport findPageByCriteria G5UNW<P2C
v %S$5
(final DetachedCriteria detachedCriteria, finalint 3A3WD+[L
pEY zB;
pageSize, RggO|s+0;
finalint startIndex){ |&~);>Cq2
return(PaginationSupport) wvH*<,8Vq
twp~#s:\z
getHibernateTemplate().execute(new HibernateCallback(){ ~/!jKH7`j
publicObject doInHibernate 7lAn GP.;
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(Session session)throws HibernateException { \7Fp@ .S3
Criteria criteria = 5Z[HlN|-!
"F?p Y@4
detachedCriteria.getExecutableCriteria(session); |al'_s}I
int totalCount = :!fU+2$`^(
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((Integer) criteria.setProjection(Projections.rowCount *7C l1o
6G:7r [
()).uniqueResult()).intValue(); ;JX2ebx
criteria.setProjection z=TuUl@
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yZ
(null); Se[>z(
List items = k!!d2y6
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criteria.setFirstResult(startIndex).setMaxResults %Z yt;p2
jtPHk*>^wu
(pageSize).list(); >ajcfG.k(
PaginationSupport ps = D"P<;@ef
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new PaginationSupport(items, totalCount, pageSize, g8]$BhRIfr
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startIndex); L]=LY
return ps; Z
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} >n5Kz]]%
}, true); 6}:(m#+
} q ;e/gP2
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public List findAllByCriteria(final oMKG M@V
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DetachedCriteria detachedCriteria){ IDp2#qg_
return(List) getHibernateTemplate hlHle\[ds
o6 8;-b'n
().execute(new HibernateCallback(){ muKjeg'b
publicObject doInHibernate (~^KXJ{->
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(Session session)throws HibernateException { n0w0]dJ&lc
Criteria criteria = xfA@GYCfT
sfC/Q"Zs
detachedCriteria.getExecutableCriteria(session); #ihHAiy3
return criteria.list(); uC"Gm;0
} `Wu.wx
}, true); `12Y2W 9
} 3#h@,>Z;
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public int getCountByCriteria(final d4LH`@SUZ-
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DetachedCriteria detachedCriteria){ OmaG|2u
Integer count = (Integer) e_llW(*l8^
da$ErN'{
getHibernateTemplate().execute(new HibernateCallback(){ 5,du2
publicObject doInHibernate !8o;~PPVl
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(Session session)throws HibernateException { IKnXtydeI}
Criteria criteria = qhNYQ/uS
t8Giv89{
detachedCriteria.getExecutableCriteria(session); &FDWlrGg
return =2d h}8Mz
^/7Y3n!|3
criteria.setProjection(Projections.rowCount %&iWc_"
f:h<tlob
()).uniqueResult(); !3Q^oR
} 2bTM0-
}, true); 3NrWt2?
return count.intValue(); oTf^-29d
} |]OI)w*
} z_87;y;=
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用户在web层构造查询条件detachedCriteria,和可选的 D=~3N
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 -nk0Q_7N
p;LF-R
PaginationSupport的实例ps。 :JzJ(q/
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ps.getItems()得到已分页好的结果集 @;{iCVW
ps.getIndexes()得到分页索引的数组 g;!,2,De}
ps.getTotalCount()得到总结果数 L_fiE3G|>
ps.getStartIndex()当前分页索引 /XwwB
ps.getNextIndex()下一页索引 nY_+V{F
ps.getPreviousIndex()上一页索引 >\>!Q V1@
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u]Dds;~"b
B@,#,-=
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 E^t}p[s
2$?j'i!
,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 G4)X~.Fy
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一下代码重构了。 O+o_{t\R
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我把原本我的做法也提供出来供大家讨论吧: \>
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首先,为了实现分页查询,我封装了一个Page类: P6;Cohfh
java代码: p}h9>R
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/*Created on 2005-4-14*/ Yx<wYzD
package org.flyware.util.page; m/NXifi8l
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/** jLreN#:9
* @author Joa PA>su)N$
* 1'9YY")#
*/ k_7agW
publicclass Page { cy#N(S[ 1
G1/
/** imply if the page has previous page */ aTPmW]w6
privateboolean hasPrePage; 1#^r5E4
XN~r d,MZ%
/** imply if the page has next page */ 5w@Q %'o`I
privateboolean hasNextPage; rfhvd wwD
x-@6U
/** the number of every page */ nh%Q";
privateint everyPage; f}+8m .g2
D2Dk7//82Y
/** the total page number */ `r.
privateint totalPage; Mt+ggF.
XnV$}T:?X
/** the number of current page */ 3ypf_]<
privateint currentPage; firiYL"=44
VseeU;q
/** the begin index of the records by the current s@5r}6?M
[USE&_RN
query */ u
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privateint beginIndex; &!O~ f
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\UBQ:+3
/** The default constructor */ '@eH)wh@m)
public Page(){
FK| q*
F(;C \[Ep
} =bB7$#al
73kL>u
/** construct the page by everyPage g+M& _n
* @param everyPage 'Mm=<Bh
* */ ]$?\,`
public Page(int everyPage){ FK.Qj P:
this.everyPage = everyPage; P};GcV-
} uM('R;<^
g'1ASMuR
/** The whole constructor */ \9s x_T
public Page(boolean hasPrePage, boolean hasNextPage, RaLc}F)9
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int everyPage, int totalPage, Shb"Jc_i
int currentPage, int beginIndex){ RT+_e
this.hasPrePage = hasPrePage; nV&v@g4Tt
this.hasNextPage = hasNextPage; 9U~sRj=D
this.everyPage = everyPage; Z;nUS,?om
this.totalPage = totalPage; 41jlfKiOm
this.currentPage = currentPage; 2K$#U|Qi
this.beginIndex = beginIndex; 4+15`
} L\("
g\foBK:GE
/** k;?E,!{
* @return :pPn)j$
* Returns the beginIndex. ~TfQuIvQB
*/ Ve^rzGU
publicint getBeginIndex(){ j\.\ePmk]
return beginIndex; Z7Xic5PI{4
} eFdN"8EW
WHvU|rJ
/** L% ?3VW
* @param beginIndex ##clReS
* The beginIndex to set. ?br 4 wl
*/ [u}2xsSx
publicvoid setBeginIndex(int beginIndex){ m kHcGB!~
this.beginIndex = beginIndex; 3Mt Alc0xp
} UV8K$n<
W05>\Rl
/** N"rZK/@}
* @return dt|f4XWF
* Returns the currentPage. Q XV8][
*/ qb1[-H
publicint getCurrentPage(){ u#`FkuE\}
return currentPage; ;f)o_:(JJ
} Wg
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iHL`r1I!
/** 2OQDG7#Kc
* @param currentPage B!zqvShF
* The currentPage to set. cJ!C=J
*/ ,=Fn6'
publicvoid setCurrentPage(int currentPage){ yCG<qQz
this.currentPage = currentPage; S2*ER
} auT'ATW7i
yCOIv!/zy
/** s;4r)9Uvx
* @return Yl$Cj>FG
* Returns the everyPage. Du."O]syD
*/ t?:Q
publicint getEveryPage(){ V_-{TGKX
return everyPage; s/J/kKj*s
} d T*8I0\+
h1 (MvEt
/** #-Ad0/
* @param everyPage [Y=X^"PF
* The everyPage to set. ,,KGcDBj
*/ <UMT:`h1MZ
publicvoid setEveryPage(int everyPage){ 37QXML
this.everyPage = everyPage; ~ GW8|tw
} "~HV!(dRMC
-L%2*`-L$
/** j1{\nP/
* @return uepL"%.@7|
* Returns the hasNextPage. ]h6mJ{k
*/ a4L0Itrp
publicboolean getHasNextPage(){ pRLs*/Bw
return hasNextPage; lSk<euCYs
} czv )D\*
=YRN"
/** ^#A[cY2eM
* @param hasNextPage SJdi*>
* The hasNextPage to set. r9d dVD
*/ C5^eD^[c
publicvoid setHasNextPage(boolean hasNextPage){ }475c{
this.hasNextPage = hasNextPage; @lnM%
} x6 c#[:R&
<7%4=
/** p~xrl jP$
* @return :xP$iEA`G
* Returns the hasPrePage. XgmblNp1
*/ N2x!RYW
publicboolean getHasPrePage(){ Vt!<.8&`
return hasPrePage; _noQk3N
} \"u3x.!
"=BO,see9
/** {UR&Y
* @param hasPrePage J|BZ{T}d
* The hasPrePage to set. XN=Cq*3}
*/ U~w g'
publicvoid setHasPrePage(boolean hasPrePage){ MN22#G4j^w
this.hasPrePage = hasPrePage; ,LHQ@/}A C
} mzX <!
l6S6Y
/** 2i@t;h2E
* @return Returns the totalPage. !&Z,ev
* -MqWcB9&
*/ k9^Vw+$m
publicint getTotalPage(){ #Rkld v'
return totalPage; b:iZ.I
} MK<VjpP0(
9A4h?/
/** @-ma_0cZQ
* @param totalPage g#ZuRL
* The totalPage to set. !^|%Z
*/ r_kw "9
publicvoid setTotalPage(int totalPage){ ab=s+[r1
this.totalPage = totalPage; ;Q]j"1c
} Gkr^uXNg#
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} R "&(Ae?LR
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K<
4P>tGO&*x
Uq,M\V\
$pT%7jV}
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 <}E^r_NvD
IFX|"3[$
个PageUtil,负责对Page对象进行构造: [wM<J$=2
java代码: m7XJe[O
a#0GmK
/Jc?;@{
/*Created on 2005-4-14*/ yt&eY6Xp
package org.flyware.util.page; QS~;C&1Hl
')9%eBaeK
import org.apache.commons.logging.Log; 0)8QOTeT
import org.apache.commons.logging.LogFactory; G=8w9-Ww
aqb;H 'F
/** )6?.; B
* @author Joa !_`T8pJ`
* vl@t4\@3
*/ 1 ]@}+H
publicclass PageUtil { wjmZ`UMz
bw7!MAXd
privatestaticfinal Log logger = LogFactory.getLog %;0w2W
fxDY:l
(PageUtil.class); hG,gY;&[6
4Pljyq:
/** <(JsB'TK
* Use the origin page to create a new page xrT_ro8
* @param page j}R4mh
* @param totalRecords !40t:+I
* @return I`%=&l[v_5
*/ wYf=(w\c
publicstatic Page createPage(Page page, int ]
%*970
H&L=WF+x
totalRecords){ vtFA#})~
return createPage(page.getEveryPage(), oT5xe[{yj
#^Dc:1,
page.getCurrentPage(), totalRecords); SPV'0* Z
} K]bS:[34 R
3D~Fu8Hg1
/** ~MY(6P
* the basic page utils not including exception B-[SUmHr
;f-|rC_"
handler W4CI=94
* @param everyPage $/C<^}A
* @param currentPage oQDOwM,
* @param totalRecords JLAg-j2
* @return page \i-jME(sN
*/ c
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publicstatic Page createPage(int everyPage, int *eXO?6f%s^
^c]Sl
currentPage, int totalRecords){ L\og`L)5\
everyPage = getEveryPage(everyPage); ZZC=
7FB
currentPage = getCurrentPage(currentPage); dW7dMx
int beginIndex = getBeginIndex(everyPage, 1A-8,)
Hcd> \0
currentPage); +29;T0>a
int totalPage = getTotalPage(everyPage, T , =ga
P&aH6*p1
totalRecords); ud:?~?j&w
boolean hasNextPage = hasNextPage(currentPage, U8-9^}DBA
Y%:p(f<
totalPage); "|DR"rr'j
boolean hasPrePage = hasPrePage(currentPage); !E_uQ?/w]Z
73~Mq7~8
returnnew Page(hasPrePage, hasNextPage, UKK}$B
everyPage, totalPage, M{kPEl&Z
currentPage, 6sy%KO*A
F'CUkVC0~P
beginIndex); >2syF{`j
} f9- |!]s
z% /ww7H
privatestaticint getEveryPage(int everyPage){ >KY\Bx
return everyPage == 0 ? 10 : everyPage; >q &ouVE
} *A\NjXJl~
SA>;]6)`(
privatestaticint getCurrentPage(int currentPage){ .%wEuqW=0
return currentPage == 0 ? 1 : currentPage; ^y6Pkb
P
} E2*"~gL^,
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privatestaticint getBeginIndex(int everyPage, int Mty]LMK
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currentPage){ GPx S.&
return(currentPage - 1) * everyPage; uWnS<O
} ['km'5uZ^
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privatestaticint getTotalPage(int everyPage, int IPxfjBC+J
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totalRecords){ g41Lh3dj
int totalPage = 0; nnGA_7-t
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if(totalRecords % everyPage == 0) T4!]^_t^
totalPage = totalRecords / everyPage; NuO>zAu
else <uTsXv
totalPage = totalRecords / everyPage + 1 ; <Z8] W1)
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return totalPage; 6vaxp|D
} $g$`fR)
)ql?}
privatestaticboolean hasPrePage(int currentPage){ #6H<JB
return currentPage == 1 ? false : true; pV("NJj!
} J#x91Jh
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privatestaticboolean hasNextPage(int currentPage, ,;d9uG2
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int totalPage){ Ba+OoS
return currentPage == totalPage || totalPage == iz^wBQ
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0 ? false : true; hE6tu'
} ewY[vbF
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} fBLd5
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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。 S-/#3
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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 Qx,G3m[}
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做法如下: bp$jD
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 O(~Vvoq
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的信息,和一个结果集List: g^C6"rsnl
java代码: !>:tF,fcB
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/*Created on 2005-6-13*/ r#Fu<so,
package com.adt.bo; qJ/C*Wqic
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import java.util.List; *"CvB{XF&Z
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import org.flyware.util.page.Page; I coL/7k3
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/** %xfy\of+Nk
* @author Joa $"FdS,*qKl
*/ F:@Ixk?E
publicclass Result { }6bLukv
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private Page page; #CS>A#Lk
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private List content; 2bJFlxEU
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/** 9>#|~P&FE
* The default constructor % KA/
*/ 3-R3Qlr
public Result(){ 0hkuBQb\
super(); 3PA'Uk"5Z
} >" .qFn g
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/** ?W
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* The constructor using fields :65HMWy.
* f$>orVm%.
* @param page
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* @param content cBI)?
*/ 1pb;A;F,A
public Result(Page page, List content){ 0uz"}v)
this.page = page; Rpk`fxAO
this.content = content; `"H?nf0
} Ds87#/Yfv
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/** (OqJet2{+
* @return Returns the content. X4$e2f
*/ %)9]dOdOk
publicList getContent(){ gxOmbQt@;
return content; V</T$V$
} >u)ZT
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/** T]|O/
* @return Returns the page. gn"&/M9E
*/ 17cW8\
public Page getPage(){ 'u[o`31.
return page; sPg6eAd~?
} k^pu1g=6I
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/**
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* @param content $Jm2,Yv
* The content to set. hPxI&
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*/ `&_k\/
public void setContent(List content){ 1J"9r7\
this.content = content; <~M9nz(<