Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 -mev%lV
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 fhBO~o+K>
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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 *G%1_
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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 e5*5.AB6&
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。 (cOND/S
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分页支持类: nx!qCgo
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java代码: Ns+)Y^(5
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package com.javaeye.common.util; HGP%a1RF#
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import java.util.List; @+0@BO12
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publicclass PaginationSupport { w0a+8gexi
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publicfinalstaticint PAGESIZE = 30; kjLsk-
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privateint pageSize = PAGESIZE; &A ;3; R
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privateList items; `^XRrVX<
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privateint totalCount; FbNH+?
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privateint[] indexes = newint[0]; EmtDrx4!(f
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privateint startIndex = 0;
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public PaginationSupport(List items, int H{ n>KZ]\
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totalCount){ _1w.B8Lyz@
setPageSize(PAGESIZE); D-TNFYYy2
setTotalCount(totalCount); 1=9qAp;?o
setItems(items); r+{!@`dYi
setStartIndex(0); #hy5c,}>
} ugIm:bg&
Ct =E;v7}
public PaginationSupport(List items, int m6~ sKJV
?MV[=LPL
totalCount, int startIndex){ Jf%!I
setPageSize(PAGESIZE); ,mO(!D
setTotalCount(totalCount); O+(. 29
setItems(items); fd!pM4"0
setStartIndex(startIndex); ++J Bbuzj!
} .XV]<)<K$
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public PaginationSupport(List items, int +BtLyQ
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totalCount, int pageSize, int startIndex){ k=h/i8i2z
setPageSize(pageSize); 5p]urfN-f
setTotalCount(totalCount); WryW3];0OR
setItems(items); )*^OPVt
setStartIndex(startIndex); >j(I[_g
} gZ`#tlA~
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publicList getItems(){ E i\J9zt
return items; 0,vj,ic*WX
} :|3"H&FWK
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publicvoid setItems(List items){ Mv7w5vTl
this.items = items; FT3,k&i
} ~n8Oyr
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publicint getPageSize(){ #GDh/t2@
return pageSize; xoz*UA.
} 8^P2GG'+-
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publicvoid setPageSize(int pageSize){ *'s2
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this.pageSize = pageSize; GDo)6du
} c"%_]7
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publicint getTotalCount(){ ~L\( /[
return totalCount; T 9<H%iF
} ;i-D~Np|
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publicvoid setTotalCount(int totalCount){ ^V XXq
if(totalCount > 0){ HonAK
this.totalCount = totalCount; "EOk^1,y
int count = totalCount / eSvc/ CU
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pageSize; :r
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if(totalCount % pageSize > 0) z/P^-N>
count++; A_6/umF[ZA
indexes = newint[count]; >"sKfiM)b
for(int i = 0; i < count; i++){ 0f=N3)
indexes = pageSize * j-I6QUd
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i; 6,g5To#vw
} r$3~bS$]
}else{ N)
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this.totalCount = 0; 1v[#::Bs
} _Sk<S
} ;8%@Lan
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publicint[] getIndexes(){ ?4wehcZz
return indexes; X."h Tha5
} dp// p)B>
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publicvoid setIndexes(int[] indexes){ GH; F3s
this.indexes = indexes; O'&X aaZV
} fdCxMKlu;
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publicint getStartIndex(){ mISuo
return startIndex; of[|b{Ze4~
} yN WbI0a
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publicvoid setStartIndex(int startIndex){ 6M<mOhp@}n
if(totalCount <= 0) Op$J"R
this.startIndex = 0; *]>OCGsr
elseif(startIndex >= totalCount) [hv3o0".
this.startIndex = indexes h>L6{d1
#r:Kg&W2FO
[indexes.length - 1]; MeK\eZ\
elseif(startIndex < 0) 9/X v&<Tn
this.startIndex = 0; .U(SkZ`6
else{ -fSKJo#}|
this.startIndex = indexes i/O,`2
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[startIndex / pageSize]; ++p&
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} G.q^Zd#.T
} v;F+fOo
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publicint getNextIndex(){ 9^Vx*KVrU
int nextIndex = getStartIndex() + w_z^5\u0
a,0o{*(u$
pageSize; vS*0CR\
if(nextIndex >= totalCount) @R-~zOv
return getStartIndex(); u7y7
else nE"b`
return nextIndex; .}hZ7>4-
} lA^Kh
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publicint getPreviousIndex(){ n'ca*E(
int previousIndex = getStartIndex() - }Bod#|`
$O]E$S${
pageSize; We+FP9d %
if(previousIndex < 0) ;u-< {2P
return0; kAQ\t?`x
else &_%+r5
return previousIndex; <2@<r
t{
} <hF~L k ,
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} RWh}?vs_
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抽象业务类 fPk9(X;G!p
java代码: b8b PK<
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/** +KwF
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* Created on 2005-7-12 d[Fr
*/ 5_tK3Q8?
package com.javaeye.common.business; u%IKM\
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import java.io.Serializable; MIyLQ
import java.util.List; 5tCq}]q#P
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import org.hibernate.Criteria; "y
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import org.hibernate.HibernateException; 7Hkf7\JY
import org.hibernate.Session; 3v3Va~fm`
import org.hibernate.criterion.DetachedCriteria; 2.&V
import org.hibernate.criterion.Projections; 1oW]O@R
import d<cbp[3F
Y X{
org.springframework.orm.hibernate3.HibernateCallback; [Oy2&C
import AFhG{G'W
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org.springframework.orm.hibernate3.support.HibernateDaoS 8/kO9'.P
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upport; o >4>7
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import com.javaeye.common.util.PaginationSupport; Ky~~Cd$
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public abstract class AbstractManager extends E,?aBRxy
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HibernateDaoSupport { y2% ^teXk
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privateboolean cacheQueries = false; d=OO(sf
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privateString queryCacheRegion; e=Tc(Mwn
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publicvoid setCacheQueries(boolean waq_ d.
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cacheQueries){ /g-X=|?F
this.cacheQueries = cacheQueries; GDQg:MgX
} 3\l9Sf=M|
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publicvoid setQueryCacheRegion(String cz~11j#
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queryCacheRegion){ 2+Y`pz47W
this.queryCacheRegion = iwTBE]J
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queryCacheRegion; ;A'17B8
} A(sx5Ynp
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publicvoid save(finalObject entity){ oW1olmpp=
getHibernateTemplate().save(entity); D~?*Xv]s~
} &$Ip$"H
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publicvoid persist(finalObject entity){ 9@>hm>g.
getHibernateTemplate().save(entity); zyn =Xv@p
} b020U>)v
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publicvoid update(finalObject entity){ _~&vs<
getHibernateTemplate().update(entity); ['`'&+x&!
} MP&4}De
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publicvoid delete(finalObject entity){ g#nsA(_L
getHibernateTemplate().delete(entity); |2` $g
} Z"nuO\zH~
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publicObject load(finalClass entity, t7%Bv+Uo
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finalSerializable id){ aL6 5t\2
return getHibernateTemplate().load dOgM9P
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(entity, id); ]-OkW.8d1
} J3E:r_+
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publicObject get(finalClass entity, ?^GsR[-x
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finalSerializable id){ GB Un" _J
return getHibernateTemplate().get 9
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(entity, id); WoR**J?}w
} hpKc_|un
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publicList findAll(finalClass entity){ _
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return getHibernateTemplate().find("from QZP;k!"w
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" + entity.getName()); 3+PM_c)Y
} }i~ j"m
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publicList findByNamedQuery(finalString Cagq0-:(p
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namedQuery){ -<.NEV
return getHibernateTemplate ur5n{0#
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().findByNamedQuery(namedQuery); (~o+pp!
} +T;qvx6
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publicList findByNamedQuery(finalString query, Ghe=hhZ
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finalObject parameter){ P3>2=qK"E(
return getHibernateTemplate t')I c6.?i
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().findByNamedQuery(query, parameter); Pk2"\y@q/
} @35]IxD
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publicList findByNamedQuery(finalString query, |%9~W^b
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finalObject[] parameters){ m8`A~
return getHibernateTemplate pgi7 JQ
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().findByNamedQuery(query, parameters); pc>R|~J{2
} HX[#tT|m~
!%=k/|#
publicList find(finalString query){ evP`&23tP
return getHibernateTemplate().find (ZJ_&8C#
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(query); CiFbk&-g
} sk/Mh8z
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publicList find(finalString query, finalObject 3e:y?hpeL
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parameter){ IS~oyFS
return getHibernateTemplate().find (~4AG \
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(query, parameter); ?,[w6O*
} m-]"I8[
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public PaginationSupport findPageByCriteria 1owoh,V6
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(final DetachedCriteria detachedCriteria){ P n DZi
return findPageByCriteria &aU+6'+QXB
C2T,1 =
(detachedCriteria, PaginationSupport.PAGESIZE, 0); OYkd?LN
} ^
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public PaginationSupport findPageByCriteria 7[PXZT
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(final DetachedCriteria detachedCriteria, finalint UgJHSl
$6[]c)(
startIndex){ 2J5dZYW
return findPageByCriteria nNr3'6lz
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(detachedCriteria, PaginationSupport.PAGESIZE, ubw ]}sfM#
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startIndex); s Y,3
} 1zffPC8jl
qn .
public PaginationSupport findPageByCriteria 4+0Zj+
q";
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(final DetachedCriteria detachedCriteria, finalint a &j?"o
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pageSize, iJK9-k~
finalint startIndex){ I <7K^j+5:
return(PaginationSupport) jdzV&
}\ F>z
getHibernateTemplate().execute(new HibernateCallback(){ 6)8']f
publicObject doInHibernate +}!eAMQ
}% =P(%-
(Session session)throws HibernateException { ))Nc|`
Criteria criteria = 0#ph1a<
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detachedCriteria.getExecutableCriteria(session); pJIH_H
int totalCount = "#()4.9
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((Integer) criteria.setProjection(Projections.rowCount KRQ/wuv
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()).uniqueResult()).intValue(); >;Bhl|r~z
criteria.setProjection F&\o1g-L
{XAKf_Cg
(null); [g{}0[ew
List items = *w;f\zW
)]}*oO
criteria.setFirstResult(startIndex).setMaxResults A,osrv
@UA>6F
(pageSize).list(); :5(TOF
PaginationSupport ps = LLMkv!%D
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new PaginationSupport(items, totalCount, pageSize, sr\MQ?\fB
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startIndex); 9f
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return ps; m-:k]9I
} tP UQ"S
}, true); +1Uw <~
} Kfi A 7W
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public List findAllByCriteria(final psMagzr&)e
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DetachedCriteria detachedCriteria){ LZeR.8XM>
return(List) getHibernateTemplate BBX4^;t
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().execute(new HibernateCallback(){ o8" [6Ys
publicObject doInHibernate H/b(dbs
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(Session session)throws HibernateException { m=R4A4Y7
Criteria criteria = mb#)w`<
@ZmpcoDI
detachedCriteria.getExecutableCriteria(session); :KFhryN
return criteria.list(); Vq*p?cF .
} q/[)mr|~
}, true); .sLx6J%
} dO=<3W
j>6{PDaT
public int getCountByCriteria(final 9SrV,~zD
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DetachedCriteria detachedCriteria){ T57S!CJ^$5
Integer count = (Integer) 27MgwX
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getHibernateTemplate().execute(new HibernateCallback(){ 1q*3V8
publicObject doInHibernate r4-r
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(Session session)throws HibernateException { 0I.7I#'3O
Criteria criteria = *33Zt+
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detachedCriteria.getExecutableCriteria(session); }SYvGp{J,
return {30A1>0#P
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criteria.setProjection(Projections.rowCount ]!f=b\-Av
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()).uniqueResult(); ''V:+@Toh
} $`uL^ hlj]
}, true); ;xb:{?
return count.intValue(); A5z`3T;1
} `'g%z: ~
} WB= gN:?
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用户在web层构造查询条件detachedCriteria,和可选的 HK }C<gg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 m:'fk;khN
1(m89C[
PaginationSupport的实例ps。 f#[Fqkmj
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ps.getItems()得到已分页好的结果集 7VR+EV
ps.getIndexes()得到分页索引的数组 #wt#-U;
ps.getTotalCount()得到总结果数 0{ \AP<
ps.getStartIndex()当前分页索引 @k6>&PS
ps.getNextIndex()下一页索引 Yw./V0Z{@
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 X+iUT
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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 XO219
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一下代码重构了。 b1_HDC(
8nNRn[oS
我把原本我的做法也提供出来供大家讨论吧: W*N^G p@
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首先,为了实现分页查询,我封装了一个Page类: 06L/i,
java代码: S)p1[&" M
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/*Created on 2005-4-14*/ ;j S~0R
package org.flyware.util.page; A[^fG_l4
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/** *GD?d2.6j
* @author Joa R0AVAUG
* <w<&,xM
*/ p"3_u;cN
publicclass Page { ~^
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!5&%
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/** imply if the page has previous page */ ~:v" TuuK
privateboolean hasPrePage; n YWS'i@
]|'Mf;
/** imply if the page has next page */ r+ k5Bk'
privateboolean hasNextPage; i#=s_v8
O6 bB CF;
/** the number of every page */ %,1bh
privateint everyPage; =UT*1-yhR
yMB*/vs
/** the total page number */ xXQDHc-Ba
privateint totalPage; )BmK'H+l
+<7`Gn(n3
/** the number of current page */ |]*]k`o<)
privateint currentPage; v?vm-e
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/** the begin index of the records by the current oYI7 .w
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query */ *\L\Bzm
privateint beginIndex; ncjtv"2R
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/** The default constructor */ ?@!dc6
public Page(){ ]Vuq)#
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} /p}^Tpu
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/** construct the page by everyPage oF7o"NHaWa
* @param everyPage ^Cs?FF@P
* */ !hdOH3h =
public Page(int everyPage){ 76Ho\}-U">
this.everyPage = everyPage; =^%#F~o:
} YEqZ((H
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/** The whole constructor */ sT
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public Page(boolean hasPrePage, boolean hasNextPage, K*NCIIDh
s"gNHp.oF
mW-4
int everyPage, int totalPage, AXFQd@#
int currentPage, int beginIndex){ ^~XsHmcQ
this.hasPrePage = hasPrePage; }V:ZGP#!'
this.hasNextPage = hasNextPage; SoC3)iqv/
this.everyPage = everyPage; `\Z7It?aDs
this.totalPage = totalPage; 7|bzopLJk
this.currentPage = currentPage; "&lQ5]N.%
this.beginIndex = beginIndex; H!PMb{e
} %zsY=qT
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/** Okxuhzn>"
* @return KsVN<eR{
* Returns the beginIndex. 7.}Vvg#G
*/ j%%& G$Tfu
publicint getBeginIndex(){ I5Vp%mCY
return beginIndex; T8'm{[C
} WOkAma-
Pk)>@F<
/** QPr29
* @param beginIndex _/xA5/V
* The beginIndex to set. awu18(;J
*/ 2nz^%pLT
publicvoid setBeginIndex(int beginIndex){ IqD;*
this.beginIndex = beginIndex; ^6g^ Q*"
} .0 }eg$d
}Y9= 3X
/** x6N)T4J(
* @return |0^~S
* Returns the currentPage. EIdEXAC(
*/ FglW|Hwy
publicint getCurrentPage(){ ]40@yrc
return currentPage; CmP_9M?ce
} Q^trKw~XNy
rHngYcjR
/** Q> d<4]`
* @param currentPage
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* The currentPage to set. mQd
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*/ z.Y`"B'j`
publicvoid setCurrentPage(int currentPage){ {mO QRAKl
this.currentPage = currentPage; w{+G/Ea
} }aSTo"~m#
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/** [a201I0 -
* @return o|`%>&jP
* Returns the everyPage. {wJ8%
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*/ +PAb+E|,
publicint getEveryPage(){ {#U3A_y
return everyPage; W!jg
} t nvCtuaR
e)BU6m%
/** ~S\y)l\wZ
* @param everyPage y).dw(
* The everyPage to set. 2UbTKN
*/ M1HGXdN* B
publicvoid setEveryPage(int everyPage){ #EG$HX]
this.everyPage = everyPage; wa1Qt
} y\?NB:=%
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/** %r
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* @return 0^('hS&
* Returns the hasNextPage. omu)s
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*/ xu<oQBt
publicboolean getHasNextPage(){ \0fS;Q^{j
return hasNextPage; z ?L]5m`H
} }ebu@)r
"rVf{
/** 8.WZC1N
* @param hasNextPage $ VTk0J-W
* The hasNextPage to set. u;G-46
*/ 2QIx~Er
publicvoid setHasNextPage(boolean hasNextPage){ Ci9]#)"c
this.hasNextPage = hasNextPage; >S}^0vNZX
} +d!"Zy2|B
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/** i K,^|Q8
* @return ]iezwz`'
* Returns the hasPrePage. \p.eY)>
*/ as^!c!
publicboolean getHasPrePage(){ CpLLsp hy
return hasPrePage; qxbGUyH==
} T/$hN hQK
FKWL{"y
/** 2 Q}^<^r
* @param hasPrePage '5etZ!:
* The hasPrePage to set. 1fMl8[!JLu
*/ XMlcY;W
publicvoid setHasPrePage(boolean hasPrePage){ b|Sjh;
this.hasPrePage = hasPrePage; 3]rd!Gp=*
} S;tv4JY
Jp 7m$D%
/** %X -G(Z
* @return Returns the totalPage. ~O8Xj6
* *f-8egt-
*/ \AY*x=PF
publicint getTotalPage(){ (|dN6M-.K
return totalPage; UFPSQ
} 8i~n;AhDs
vYNu=vnM
/** |2!cPf^8
* @param totalPage q?$<{Z"
* The totalPage to set. } m&La4E
*/ \O=t5yS
publicvoid setTotalPage(int totalPage){ }@TtX\7(D
this.totalPage = totalPage; @+&QNI06S
} A(1dq
<IwfiI3y
}
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|5g1D^b]s^
x.%x|6G*
+Z/aB*aVa^
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 PzH#tG&.j
J_7&nIH7
个PageUtil,负责对Page对象进行构造: -p*j9
z
java代码: N
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/*Created on 2005-4-14*/ }ZB:nnG
package org.flyware.util.page; ay>u``$R
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import org.apache.commons.logging.Log; XK,l9 {*
import org.apache.commons.logging.LogFactory; :<PwG]LO
[DSD[[
z[
/** S*'
* @author Joa Z"5ewU<?
* &Ef_p-e-P
*/ #G\;)pT
publicclass PageUtil { m!sMr^W
E3d# T
privatestaticfinal Log logger = LogFactory.getLog AfX lV-v
(0!U,8zz
(PageUtil.class); 8omk4 ;
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/** dS)c~:&+
* Use the origin page to create a new page cUD}SOW
* @param page V[fcP;
* @param totalRecords CAtdx!
* @return Y N*"q'Yz_
*/ H q."_i{I
publicstatic Page createPage(Page page, int -iySU 6
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totalRecords){ |yYu!+U
return createPage(page.getEveryPage(), 2>h.K/pC
n+H);Dg<8
page.getCurrentPage(), totalRecords); p?Jx2(%m
} |n*<H|
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/** ZE4xF8
* the basic page utils not including exception f{ER]U
a9niXy}a(
handler <69Uq8GI
* @param everyPage by@}T@^\
* @param currentPage `>N_A!pr`
* @param totalRecords .!yw@kg
* @return page v6*8CQ+
*/ <j&LC
/]o
publicstatic Page createPage(int everyPage, int U`)o$4Bq
K pSho<
currentPage, int totalRecords){ 99u9L)
everyPage = getEveryPage(everyPage); xAJuIR1Hi
currentPage = getCurrentPage(currentPage); HiPd|D
int beginIndex = getBeginIndex(everyPage, D&nVkZP>
K[M[0D
currentPage); G;yh$n<"
int totalPage = getTotalPage(everyPage, +/Qgl
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totalRecords); 9MR,3/&N
boolean hasNextPage = hasNextPage(currentPage, Mhiz{Td
~ -zch=+u
totalPage); V^E.9fs,
boolean hasPrePage = hasPrePage(currentPage); wC>Xu.Z:
$|n#L6k
returnnew Page(hasPrePage, hasNextPage, HRF;qR9v
everyPage, totalPage, KSB{Z TE
currentPage, >q^l
vY'E+M"+@
beginIndex); qgk6 \&K[
} %eQw\o,a
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privatestaticint getEveryPage(int everyPage){ W=ar&O~}n
return everyPage == 0 ? 10 : everyPage; uBqZ62{G
} AD4Ot5
*Rj(~Q/t
privatestaticint getCurrentPage(int currentPage){ sJB::6+1(|
return currentPage == 0 ? 1 : currentPage; ar[*!:!
} = 6^phZ(
3e7P
w`gLl
privatestaticint getBeginIndex(int everyPage, int \&.]!!Q
gbL!8Z1h
currentPage){ a@}A;y'd
return(currentPage - 1) * everyPage; %VmHw~xyF:
} 0
V3`rK
k-XE|v
privatestaticint getTotalPage(int everyPage, int *g~\lFX,u
z[bS
soK`
totalRecords){ q;L~5q."E
int totalPage = 0; 0VBbSn}Z<
jk-e/C
if(totalRecords % everyPage == 0) RT$.r5l_@
totalPage = totalRecords / everyPage; Yk!TQY4
else /
+9o?Kxya
totalPage = totalRecords / everyPage + 1 ; ouf91<n
64w4i)?eM[
return totalPage; & U6 bOH%P
} 3r]N\c
-
}2AXP2q
privatestaticboolean hasPrePage(int currentPage){ 1Kc[).O1
return currentPage == 1 ? false : true; 72;ot`
} +=&A1{kR3
lx"#S'^~
privatestaticboolean hasNextPage(int currentPage, eh5j
N]iu
o.
int totalPage){ Tye[iJ
return currentPage == totalPage || totalPage == 5^7q
2".
sm>5n_Vw
0 ? false : true; %jnSJjcq
} JOvRUDZ
/2#1Oi)o
Ihn+_Hu
} rj> _L
]F81N(@:F
1@L|EFa
j!;y!g
:^[HDI-[2
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。 ]31UA>/TI
Ccx1#^`
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 ?N/6m
b w2KD7
做法如下: bJ#]Xm(]D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 X
cDu&6Dy
<JNiW8 PG
的信息,和一个结果集List: jt? .g'
java代码: /;rPzP4K6
SB#Y^!
;LjTsF'
/*Created on 2005-6-13*/ rjLPX
package com.adt.bo; 1*o=I-nOa
l=.h]]`;
import java.util.List; j|/4V
a/v!W@Zz}
import org.flyware.util.page.Page; EBl? oN7E
QaYUcma~n
/** Sh+$w=vC
* @author Joa ;"N4Yflz
*/ DbH"e
publicclass Result { ,9@JBV%_
U'K{>"~1a
private Page page; !CO1I-yL
HX&G
k
private List content; ~R!M.gY[rK
y
+2
/** ]#*S. r]
* The default constructor ?!Bf# "TY
*/ 6+s10?
public Result(){ wTw)GV4
super(); 5y`n8. (?
}
iE8
Ub_!~tb}?
/** ].e4a;pt
* The constructor using fields !/;/ X\d
* &?)?
w-$p
* @param page ~#^suy?
* @param content Or9"T ]z
*/ XVwJr""+
public Result(Page page, List content){ "ytPS~
this.page = page; m:
this.content = content; _hz}I>G@B
} V~%C me
6 J
B"qd
/** pSC\[%K
* @return Returns the content. #FNSE*Y
*/ [S<1|hk
s(
publicList getContent(){ bCbp JZ
return content; ?Xq"Q^o4#e
} 9>I&Z8J$M
(O@fgBM
/** uZ/XI {/
* @return Returns the page. g;n6hXq4
*/ kQt#^pO)
public Page getPage(){ ><Awk~KR
return page; 3<%ci&B
} ^_rBEyz@
Nm.G,6<J
/** yPXa
* @param content c`E0sgp
* The content to set. %UXmWXF4$
*/ P]mJ01@'
public void setContent(List content){ r\."=l
this.content = content; ZCC T
} t|jp]Vp
jo}yeGbU
/** z?I"[M
* @param page +~[>Usf
* The page to set. 3Ud{W$Ym
*/ dWK"Tkf\
publicvoid setPage(Page page){ e\7AtlW"
this.page = page; y:Ne}S*ncE
} n)t'?7
} uK;&L?WB
-2/&i
]H$Trf:L
Svl;Ul
$2J[lt?%
2. 编写业务逻辑接口,并实现它(UserManager, h%UM<TZ]"
w}WfQj
UserManagerImpl) W Yo>Md
8
java代码: Mc@_[q!xY?
5!Ho[
`37%|e 3bQ
/*Created on 2005-7-15*/ =!N,{V_
package com.adt.service; qvC 2BQ
F6Ne?[b
import net.sf.hibernate.HibernateException; yE_T#FN
X@pcL{T!
import org.flyware.util.page.Page; nIEIb.-
Y~Z&h?H'}
import com.adt.bo.Result; uGU-MC*
[R(d Cq>
/** VoC|z Rd_
* @author Joa -2qI2Z
*/ O[j$n
publicinterface UserManager { &ev#C%Nu
:2*0Jh3_
public Result listUser(Page page)throws #9rCF 3P
Y;1s=B9
HibernateException; ql I1<Jx
|<2<`3
} [5;_XMj%
P%y9fU2[
f64}#E|w
eHc.#OA&
?`3G5at)9f
java代码: #:E^($v
wJg&OQc9
]vjMfT%]W
/*Created on 2005-7-15*/ l{8t;!2t
package com.adt.service.impl; '-V[tyE
*(o^w'5
import java.util.List; tpQ8
m(
TUX:[1~Nf[
import net.sf.hibernate.HibernateException; 7b*9
Th*a
h3(B7n7
import org.flyware.util.page.Page; }+fBJ$
import org.flyware.util.page.PageUtil; c|F2 6$rv
H)pB{W/
import com.adt.bo.Result; asL!@YE
import com.adt.dao.UserDAO; asJ t6C
import com.adt.exception.ObjectNotFoundException; %:.IG.`d
import com.adt.service.UserManager; :MILOwF
M5`wfF,j
/** DcsQ 6
* @author Joa =/kT|
*/ @5\/L6SRfL
publicclass UserManagerImpl implements UserManager { "9OOyeKu%
s@K #M
private UserDAO userDAO; Qy\Koo
jTN!\RH9NF
/** lTZcbaO?]
* @param userDAO The userDAO to set. GC)xQZU)s
*/ !$!"$-5
publicvoid setUserDAO(UserDAO userDAO){ 4~e6z(
this.userDAO = userDAO; 6D29s]h2
} eXCH*vZY
cpQhg-LY|
/* (non-Javadoc) XB+Juk&d
* @see com.adt.service.UserManager#listUser +.|8W !h`1
Ombvp;
(org.flyware.util.page.Page) ol@LLT_m
*/ =~ ="#
public Result listUser(Page page)throws N Bpf
G;;iGN
HibernateException, ObjectNotFoundException { t**o<p#)f
int totalRecords = userDAO.getUserCount(); \q:PU6q
if(totalRecords == 0) \"Aw
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throw new ObjectNotFoundException Y-G;;~
#6za
("userNotExist"); 0BQ< a
page = PageUtil.createPage(page, totalRecords); Q);^gV
List users = userDAO.getUserByPage(page); Jc, {n*
returnnew Result(page, users); S@vLh=65
} LE@`TPg$R
QiQO>r
} 'fIirGOl
WHvxBd
e]u3[ao
QVQ?a&HYS
q/^&si
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ns9a+QQ
j:J{m0
询,接下来编写UserDAO的代码: bId@V[9
3. UserDAO 和 UserDAOImpl: ,XmyC7y<
java代码: S`&YY89{&
4&^BcWqA*f
l;'c6o0e
/*Created on 2005-7-15*/ c!=^C/5Ee
package com.adt.dao; Auf2JH~
AV^Sla7|_
import java.util.List; x)!NB99(tC
s9b 6l,Z
import org.flyware.util.page.Page; ypsT:uLT
#ZPy&GIr
import net.sf.hibernate.HibernateException; or..e
\k)(:[^FY
/** |csR"DOqz
* @author Joa 9Sk?tl
*/ -<.b3M h
publicinterface UserDAO extends BaseDAO { Mwd(?o
o;2QZ"v
publicList getUserByName(String name)throws M}BqSzd*
\hFIg3
HibernateException; >$p|W~x
J,]U"+;H
publicint getUserCount()throws HibernateException; y}!}*Qj+/
BjIKs~CT
publicList getUserByPage(Page page)throws KsBi<wY
-A17tC20J1
HibernateException; \t
04-
H}B%OFI \+
} [_?dp aTt
q/HwcX+[b
mo-
Y %
0N19R 5NN8
nnPY8pdjSD
java代码: T?'Vb
o$-!E(p
XB'PEvh8
/*Created on 2005-7-15*/ by8~'?
package com.adt.dao.impl; oN6X]T<
M;K%=l$NG
import java.util.List; fG*366W
m6oaO9"K
import org.flyware.util.page.Page; l gzA) (
p2:>m\
import net.sf.hibernate.HibernateException; ,wEcRN w
import net.sf.hibernate.Query; JM-+p
Yx{q VU
import com.adt.dao.UserDAO; P85@G
2
BNe6q[ )W~
/** wc#E:GJcK
* @author Joa X,"(G}KUA
*/ mIX[HDy:V$
public class UserDAOImpl extends BaseDAOHibernateImpl Xv'5%o^i*
d~U}IMj
implements UserDAO { Juqe%he`
~E tW B
/* (non-Javadoc) I>( \B| \6
* @see com.adt.dao.UserDAO#getUserByName vMB`TpZ
Wy`ve~y
(java.lang.String) :AM5EO
*/
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publicList getUserByName(String name)throws :v>Nz7SB
z<c%Xl\$%
HibernateException { qoXncdDHZ
String querySentence = "FROM user in class HM(S}>
>MeM
com.adt.po.User WHERE user.name=:name"; n6Qsug$z
Query query = getSession().createQuery #[C=LGi
_rU%DL?
(querySentence); kg^VzNX
query.setParameter("name", name); qu:nV"~_
return query.list(); ^E^Cj;od@
} - .EH?{i
<yHa[c`L
/* (non-Javadoc) J@vL,C)E6
* @see com.adt.dao.UserDAO#getUserCount() t5Oeb<REz
*/ ?|;q=p`t-
publicint getUserCount()throws HibernateException { vRQ7=N{3
int count = 0; #7}1W[y9}l
String querySentence = "SELECT count(*) FROM NP#:} )
k ED1s's
user in class com.adt.po.User"; ^Voi4;
Query query = getSession().createQuery ~d072qUos
M)JKe!0ad1
(querySentence); ,s9gGCA
count = ((Integer)query.iterate().next A3|hFk
:_f5(N*{5o
()).intValue(); Y 3 QrD&V
return count; 2aR<xcSg
} c?0.>^,B Q
o'SZsG
/* (non-Javadoc) AYP*J
* @see com.adt.dao.UserDAO#getUserByPage @z-%:J/$
Q`kJ3b
(org.flyware.util.page.Page) :K)7_]y
*/ k:qS'
publicList getUserByPage(Page page)throws =h
Lw1~
+-*Ww5Zti
HibernateException { Jb (CH4|7
String querySentence = "FROM user in class !RD<"
3\B28m
com.adt.po.User"; 4ru-qF
Query query = getSession().createQuery -0>gq$/N=^
+338z<'Z!
(querySentence); 4{rqGC/
query.setFirstResult(page.getBeginIndex()) !F|#TETrt
.setMaxResults(page.getEveryPage()); $%P?2g"j,
return query.list(); 1R+/T
} ;#Y'SK
qLYz-P'ik
} dz>2/'
D,l&^diz
QK`5KB(k'
nR(v~_y[V
EIrAq!CA
至此,一个完整的分页程序完成。前台的只需要调用 ~Bi>T15e
S[ln||{
userManager.listUser(page)即可得到一个Page对象和结果集对象 1XpG7
nUy. gAb
的综合体,而传入的参数page对象则可以由前台传入,如果用 o#~Lb9`@U
8%ea(|Wjg
webwork,甚至可以直接在配置文件中指定。 (& UQ^
F!_8?=|
下面给出一个webwork调用示例: ``?79 MJ5
java代码: Nm7YH@x*o
Z)^1~!w0
l{o,"P"
/*Created on 2005-6-17*/ LpYG!K l
package com.adt.action.user; {TL.2
[(rT,31cW
import java.util.List; `]7==c #Y
?bH&F
import org.apache.commons.logging.Log; m0Geq.
import org.apache.commons.logging.LogFactory; }nUq=@ej
import org.flyware.util.page.Page; SYE+A`a
2t[P-on
import com.adt.bo.Result; A+w'quXn
import com.adt.service.UserService; }Be;YIhG
import com.opensymphony.xwork.Action; h0O t>e"
ZO#f)>s2
/** E#!tXO&,
* @author Joa kfV}ta'^S
*/ .<Rw16O
publicclass ListUser implementsAction{ qeUT]*
w
QJ,[K_
privatestaticfinal Log logger = LogFactory.getLog 5(=5GkE)>
9,wD
(ListUser.class); 4^Y{ BS fF
7M/v[dwL
private UserService userService; m!K`?P]:N
('k9X cTPP
private Page page; q
S qS@+p
xWnOOE$i
privateList users; xt&4]M
V
fg)VO6Wo&
/* ?:42jp3
* (non-Javadoc) T!7B0_
* )! eJW(
* @see com.opensymphony.xwork.Action#execute() AxtmG\o>
*/ D){my_
/
publicString execute()throwsException{ 48IrC_0j
Result result = userService.listUser(page); 64i*_\UKe
page = result.getPage(); g7"2}|qxo
users = result.getContent(); (QTF+~)
return SUCCESS; ![i)_XO
} 85T"(HhT
hp1+9vEN
/** -|GKtZ]}
* @return Returns the page. uCr :+"C
*/ ?o6X_UxW!
public Page getPage(){ M>_vsI^I'
return page; k-Yli21-/|
} 'eo/"~/*w
;,}Dh/&E
/** ,g pZz$Ef(
* @return Returns the users. z"97AXu
*/ n_4 r'w
publicList getUsers(){ 7 x'2
return users; uOO\!Hqq
} DL*vF>v
#CV]S4/^
/** r~z'QG6v/
* @param page iInWw"VbKe
* The page to set. W cGg
*/ 4{@{VsXN
publicvoid setPage(Page page){ BsU}HuQZQ
this.page = page; ,v<7O_A/e
} q6,z 1A"
|h?2~D!+d
/** +CM>]Ze
* @param users 4*ZY#7h
* The users to set. .ht-*
*/ E<jW;trt_
publicvoid setUsers(List users){ <2E|URo,#
this.users = users; &|<f|BMX
} iF9d?9TWl
o! l Ykud
/** )n]"~I^
* @param userService o1vK2V
* The userService to set. 5Xf]j=_
*/ q;}iW:r&Q
publicvoid setUserService(UserService userService){ \_ V*Cs
this.userService = userService; _u+ 7>
} Mj{w/'
} Pa6pq;4St
r'`7}@H*
MkL)
ZfH+Iqd
ua)jGif
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, m"T}em#
ftG3!}
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 u0GHcpOm
`BQv;NtP
么只需要: Z\$M)e8n
java代码: -V4%f{9T3
QgI[#d{
y^"@$
<?xml version="1.0"?> p- a{6<h
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~o>Gm>5!HH
Zwm/ c]6`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- W#%s0EN<_
f1]zsn:
1.0.dtd"> @0'U
p
'Oj 1@0*0
<xwork> TF%Xb>jy[
c"v75lW-J
<package name="user" extends="webwork- 6\ yBA_z
a}uYv:
interceptors"> hLbWqF
(Vr%4Z8
<!-- The default interceptor stack name %@Z;;5 L
FpiTQC7d
--> b8e\( Dww
<default-interceptor-ref u4_QLf@I
3 3|t5Ia
name="myDefaultWebStack"/> {"+M%%`*#
PJcfiRa'jQ
<action name="listUser" s-_D,$ |
=#/Kg_RKL
class="com.adt.action.user.ListUser"> m`9nDiV
<param f4fBUZ^ A
f-G)pHm
name="page.everyPage">10</param> #R{>@]x`
<result 3*&
Y'/!
*68 TTBq(
name="success">/user/user_list.jsp</result> :{2~s
</action> 0|RofL&o
?+))J~@t
</package> D3yTN"
r|=1{Nx
</xwork> Jup)A`64
ICb!AsL
v,S5C
G.H8
><%
z7ik/>d?
^3TNj
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 N(Ru/9!y"
ejlns
~
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 |82q|@e
1!KROes4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ~PI2G9
gLB(A\yG
FDQ=$w}'>
pY`$k#5
Vw1>d+<~-)
我写的一个用于分页的类,用了泛型了,hoho n&njSj/
-B H/)$-$
java代码: Ln4]uqMG.
K9lekevB
c1"wS*u
package com.intokr.util; BS*79heY
"5&"Ij,/
import java.util.List; 3uocAmY
0+e=s0s.
/** F(yR\)!C
* 用于分页的类<br> .;]WcC<3
* 可以用于传递查询的结果也可以用于传送查询的参数<br> UDh\%?j
* TKR#YJQ?K
* @version 0.01 z'U.}27&o
* @author cheng q<
XFw-Pv
*/ `qc"JB
public class Paginator<E> { AH#mL
privateint count = 0; // 总记录数 +6#$6 hG
privateint p = 1; // 页编号 Z*m^K%qJ
privateint num = 20; // 每页的记录数 9j:]<?D,A
privateList<E> results = null; // 结果 509T?\r
C2}y#A I
/** Byc;r-Q5V
* 结果总数 QN#"c
*/ G*I
publicint getCount(){ iT}>a30]B
return count; x/DV> Nfn
} M-nRhso
Voo'ZeZa
publicvoid setCount(int count){ ij$NTY=u
this.count = count; ^2~ZOP$A
} g8Ex$,\,
.;4N:*hY
/** 9^XZ|`
* 本结果所在的页码,从1开始 ^I!Z)/
* tnJ7m8JmC
* @return Returns the pageNo. O2Qmz=%
*/ MJ JC6:
publicint getP(){ [P
&B
return p; EHwb?{
} klUV&O+=%
^
8 }P_
/** l zFiZx
* if(p<=0) p=1 WqA)V,E
* K,g6y#1"
* @param p M{J>yN
*/ 9<u&27.
publicvoid setP(int p){ q-(~w!e
if(p <= 0) ni/s/^
p = 1; 6{I7)@>N
this.p = p; v 6
U!(x
} 9WG=3!-@
b-_l&;NWg
/** AwZ@)0Wy
* 每页记录数量 $mPR)T
*/ a fa\6]m
publicint getNum(){ 8xLQ"
l+"
return num; NPH(v`
} FEk9a^Xyx
mW"e
/** `,V&@}&"n
* if(num<1) num=1 jWUrw
*/ nGVr\u9z
publicvoid setNum(int num){ #`_W?-%^
if(num < 1) -9om,U`t
num = 1; u.2X"
this.num = num; m~+.vk
} fz|*Plv
2!6hB sEr
/** dEDhdF#f
* 获得总页数 %`bs<ZWT
*/ %g7j7$c
publicint getPageNum(){ < dE7+w
return(count - 1) / num + 1; TIp\-
} I;XM4a
>J9Qr#=H2
/** r3Ol?p
* 获得本页的开始编号,为 (p-1)*num+1 Xn"#Zy_
*/ efyEzL
publicint getStart(){ !S<p"
return(p - 1) * num + 1; CRo@+p10
} w?D=
]4O!q}@Cd
/** /[Nkk)8-
* @return Returns the results. d*TH$-F!p
*/ @u+LF]MY
publicList<E> getResults(){ 9vi+[3s/=;
return results; eF;Jj>\R+i
} 67/@J)z0%
p!E*ANwX
public void setResults(List<E> results){ HAc"pG
this.results = results; lGet)/w;c
} Y3|_&\v6
<YCjo[(~
public String toString(){ k Jz^\Re
StringBuilder buff = new StringBuilder #F/W_G7 v
Zq{gp1WC
(); +^J&x>5
buff.append("{"); 9|jMN
j]vo
buff.append("count:").append(count); #+i5'p(4
buff.append(",p:").append(p); )[99SM
buff.append(",nump:").append(num); #}6~>A
buff.append(",results:").append bz:En'2>F
F`;q9<NYRW
(results); pvWNiW:~k
buff.append("}"); A
_7I0^
return buff.toString(); -4Q\FLC'k
} P/S ,dhs(
s&%r?
} UN<$F yb
V%*91t _
_or_Vw!