Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 K7c[bhi_w
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Znd ,FqHk
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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 &>P<Zw-
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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 \-8S"
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分页支持类: A~({vb'
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java代码: i "d&U7Q
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package com.javaeye.common.util; <S3s==Cg
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import java.util.List; )fQ1U
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publicclass PaginationSupport { G j^*
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publicfinalstaticint PAGESIZE = 30;
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privateint pageSize = PAGESIZE; )kD B*(?
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privateList items; "p]!="\
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privateint totalCount; 89Ir}bCr
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privateint[] indexes = newint[0]; WG*),P?
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privateint startIndex = 0; hBi/lHu'
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public PaginationSupport(List items, int |]5`T9K@b#
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totalCount){ K[yP{01
setPageSize(PAGESIZE); 0.)q5B`
setTotalCount(totalCount); )H(i)$I
setItems(items); XAZPbvG|$
setStartIndex(0); /j-c29nz
} HD'adj_,
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public PaginationSupport(List items, int //'&a-%$^
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totalCount, int startIndex){ 5W0s9yD
setPageSize(PAGESIZE); 0n}v"61q
setTotalCount(totalCount); (67byO{
setItems(items); u+^KP>rM(
setStartIndex(startIndex); 8u%,5GV>Xr
} yLPP6_59$
l <p(zLR
public PaginationSupport(List items, int Y"L |D,ex
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totalCount, int pageSize, int startIndex){ @C%6Wo4l3
setPageSize(pageSize); IhRdn1&
setTotalCount(totalCount); zf>*\pZE
setItems(items); ;;6$d{
setStartIndex(startIndex); ~ #7@;C<nt
} 8@Bm2?$}g
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publicList getItems(){ P\WFm
return items; <HtGp6q
} =R<92v
}2Tq[rl~s
publicvoid setItems(List items){ Fv*Et-8tN5
this.items = items; e_"m\e#N
} $01csj
1_};!5$.
publicint getPageSize(){ 1tLEKSo+
return pageSize; --EDr>'D5P
} `NTtw;%Y
uW
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publicvoid setPageSize(int pageSize){ 3b|=V
this.pageSize = pageSize; ?GlXxx=eV
} Si@6'sw
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publicint getTotalCount(){ AOJ[/YpM
return totalCount; XhA tf@n
} I{h KN V
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publicvoid setTotalCount(int totalCount){ Y'5(exW
if(totalCount > 0){ KaX*) P
this.totalCount = totalCount; p8 Ao{
int count = totalCount / g)R 2V
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pageSize; P*H0Hwn;
if(totalCount % pageSize > 0) S}a]Bt
count++; :%Oz:YxC/
indexes = newint[count]; e"_kH_7sv
for(int i = 0; i < count; i++){ JEaTDV_
indexes = pageSize * I&m' a
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i; 8N+T=c
} 0n'vF&E8
}else{ }%z%}V@(&
this.totalCount = 0; ;>L8&m)R5
} K8Q3~bMf
} P@f#DX
)
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publicint[] getIndexes(){ C
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return indexes; KyyVO"
} _9JFlBx
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publicvoid setIndexes(int[] indexes){ D6H?*4f]
this.indexes = indexes; $8xb|S[
} h!v<J
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publicint getStartIndex(){ gO)":!_n W
return startIndex; zhm 0J-g
} C JER&"em7
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publicvoid setStartIndex(int startIndex){ lx=tOfj8
if(totalCount <= 0) ]%y>l j?Y
this.startIndex = 0;
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elseif(startIndex >= totalCount) J8i,[,KcE
this.startIndex = indexes ~\8(+qIv%f
i/skU9
[indexes.length - 1]; KPI96P
elseif(startIndex < 0) 3h:y[Vm#9y
this.startIndex = 0; gnjhy1o
else{ 7F6B
this.startIndex = indexes /`7+Gy<
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[startIndex / pageSize]; s'oNW
} [61*/=gWe
} K,I
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publicint getNextIndex(){ yi*EobP
int nextIndex = getStartIndex() + A= 5Ebu!z
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pageSize; g&y^ r/
if(nextIndex >= totalCount) Eh ";irE
return getStartIndex(); $xbW*w
else k}Q<#
return nextIndex; 6o7t eX
} Ei):\,Nv
|oke)w=gn
publicint getPreviousIndex(){ QxdC[t$Lp
int previousIndex = getStartIndex() - B~N3k
Qj;{Z*l%+
pageSize; {x.0Yh7
if(previousIndex < 0) nvT@'y+
return0; )t"-#$,@
else IlB8~{p_
return previousIndex; L/r_MtN
} &=BzsBh
?q9]H5\
} [#q]B=JB
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抽象业务类 3_Xu3hNH!
java代码: >>,G3/Zd*
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/** z__?k Y
* Created on 2005-7-12 |Z<\k x
*/ n)98NSVDbT
package com.javaeye.common.business; ,`Y$}"M4
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import java.io.Serializable; SXZ9+<\
import java.util.List; m]!hP^^
)/%5f{+}
import org.hibernate.Criteria; P+}~6}wJE
import org.hibernate.HibernateException; ft6)n T/"&
import org.hibernate.Session; 8zD>t~N2C
import org.hibernate.criterion.DetachedCriteria; !43!JfD
import org.hibernate.criterion.Projections; l^9gFp~I
import NBY|U{.g
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org.springframework.orm.hibernate3.HibernateCallback; Ly+UY.v"
import _E`+0;O
<3x%-m+p4
org.springframework.orm.hibernate3.support.HibernateDaoS 32<D9_
Qk:Lo*!
upport; <[cpaZT,
#mw!_]
import com.javaeye.common.util.PaginationSupport; @m9pb+=v
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public abstract class AbstractManager extends $M 8&&M
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HibernateDaoSupport { 31a,i2Q4
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privateboolean cacheQueries = false; oT):#,s
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privateString queryCacheRegion; **Ioy+
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publicvoid setCacheQueries(boolean {fzX2qMZ]
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cacheQueries){ j)mU`b_
this.cacheQueries = cacheQueries; }q.D)'g_
} 5]N0p,f
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publicvoid setQueryCacheRegion(String :rVR{,pL
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queryCacheRegion){ #dWz,e3
this.queryCacheRegion = Lj<TzPzg*
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queryCacheRegion; hpF_@n
} FfJp::|ddr
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publicvoid save(finalObject entity){ "/aZ*mkjfJ
getHibernateTemplate().save(entity); mvEhP{w
} j2MA['{
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publicvoid persist(finalObject entity){
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getHibernateTemplate().save(entity); -[7+g
} ?ZlXh51
})/P[^
publicvoid update(finalObject entity){ 4d@yAr}
getHibernateTemplate().update(entity); 5qtk#FB
} j%Au0k
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publicvoid delete(finalObject entity){ lPR=C0h}@
getHibernateTemplate().delete(entity); szsVk#p
} a|7C6#iz$
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publicObject load(finalClass entity, @.eN+o9|
?$f.[;mh
finalSerializable id){ 4H-eFs%5
return getHibernateTemplate().load Trv}YT.
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(entity, id); M%S7cIX
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} ?'MkaG0g
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publicObject get(finalClass entity, "`49m7q1H
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finalSerializable id){ (u@:PiU/eP
return getHibernateTemplate().get aj&L
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(entity, id); +;KUL6
} 6dIPgie3w
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publicList findAll(finalClass entity){ ]->"4,}
return getHibernateTemplate().find("from S;% &X
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" + entity.getName()); pWV_KS
} zr.\7\v
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publicList findByNamedQuery(finalString H
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namedQuery){ ~S8:xG+s
return getHibernateTemplate |U|>YA1[b
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().findByNamedQuery(namedQuery); {v|!];i
} ^1S{::
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publicList findByNamedQuery(finalString query, z{rV|vQ
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finalObject parameter){ <1|[=$w
return getHibernateTemplate Tx;a2:6\[
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().findByNamedQuery(query, parameter); ..)J6L5l
} $l]:2!R
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publicList findByNamedQuery(finalString query, k H.dtg_
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finalObject[] parameters){ FCEy1^u
return getHibernateTemplate %~!4DXrMk
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().findByNamedQuery(query, parameters); :wC\IwG~CE
} vE:*{G;Y
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publicList find(finalString query){ EQm{qc;
return getHibernateTemplate().find &: Q'X
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(query); Bh3F4k2bg7
} }>@\I^Xm,
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publicList find(finalString query, finalObject eYUb>M)
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parameter){ &<F9Z2^
return getHibernateTemplate().find l_h:S`z.
TR DQ+Z
(query, parameter); *S,~zOYN
} ix!xLm9\
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public PaginationSupport findPageByCriteria A=N$5ZJ
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(final DetachedCriteria detachedCriteria){ 7:jLZ!mgi
return findPageByCriteria 7f>=-sv
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ok:uTeJI
} S1QMS
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public PaginationSupport findPageByCriteria g:Hj1!'
~:DL{ZeEb
(final DetachedCriteria detachedCriteria, finalint xKUL}>8
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startIndex){ =]7o+L4
return findPageByCriteria p!UR;xHI\
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(detachedCriteria, PaginationSupport.PAGESIZE, o2!738
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startIndex); ?
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} S{=5nR9 j
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public PaginationSupport findPageByCriteria G2`z?);1b
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(final DetachedCriteria detachedCriteria, finalint `c
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pageSize, | b'Ut)E
finalint startIndex){ E%mEfj7
return(PaginationSupport) nfEbu4|
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getHibernateTemplate().execute(new HibernateCallback(){ 2R/|/>T v
publicObject doInHibernate F1Z'tjj+
Aw#<: 6-
(Session session)throws HibernateException { &6sF wK
Criteria criteria = bZ`v1d
(r
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detachedCriteria.getExecutableCriteria(session); cN,*QN
int totalCount = U=n7RPw
<,} h8;Fr
((Integer) criteria.setProjection(Projections.rowCount xC`!uPk/pL
,L<JG
()).uniqueResult()).intValue(); tsb[=W!Ar8
criteria.setProjection 2*Qv6
:qK
#mQ@4k9i
(null); $+4DpqJ
List items = :;{M0
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criteria.setFirstResult(startIndex).setMaxResults 9j2t|D4uT
SQN?[v
(pageSize).list(); rpow@@ad<
PaginationSupport ps = xw #CwMbbi
1:-'euA"
new PaginationSupport(items, totalCount, pageSize, H*W>v[>
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startIndex); Ta?J;&<u]/
return ps; ] ?DU8
} m{q'RAw
}, true); (:l6R9'=
} 5JzvT JMx
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public List findAllByCriteria(final eRMN=qP.q
^j}C]cq{Xg
DetachedCriteria detachedCriteria){ a'VQegP(f\
return(List) getHibernateTemplate :kgh~mx5LF
F6\{gQ<E
().execute(new HibernateCallback(){ -xtT,^<B
publicObject doInHibernate Df6i*Ko|
# h;
(Session session)throws HibernateException { k|;a"56F
Criteria criteria = {)" 3
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detachedCriteria.getExecutableCriteria(session); ~`
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return criteria.list(); 0Ui.nz j
} $TUYxf0q
}, true); u&zY>'}zm
} 5 ^{~xOM5
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public int getCountByCriteria(final R$&;
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DetachedCriteria detachedCriteria){ B!RfPk1B<*
Integer count = (Integer) u zZ|0
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getHibernateTemplate().execute(new HibernateCallback(){ o#qdgZ
publicObject doInHibernate <F9-$_m
x{R440"
(Session session)throws HibernateException { ?}HK!feU
Criteria criteria = j yHa}OT
S!?T0c?>
detachedCriteria.getExecutableCriteria(session); w.m8SvS&b
return BE?]P?r?
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criteria.setProjection(Projections.rowCount -E7mt`:d
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()).uniqueResult(); I\)`,w
} J9T2 p\5
}, true); 7@c!4hmrU
return count.intValue(); Myc-lCE
} $LXa]
} XCM!8x?K
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用户在web层构造查询条件detachedCriteria,和可选的 mb*Yw6q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 {it.F4.
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PaginationSupport的实例ps。 MdBmq/[O
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ps.getItems()得到已分页好的结果集 //8W"> u
ps.getIndexes()得到分页索引的数组 7
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ps.getTotalCount()得到总结果数 MIJuJ]U}
ps.getStartIndex()当前分页索引 dk&F?B{6T
ps.getNextIndex()下一页索引 v H HgZ
ps.getPreviousIndex()上一页索引 >iTmILA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 uda++^y:
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 R}oN8
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一下代码重构了。 7-S?RU]g
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我把原本我的做法也提供出来供大家讨论吧: Xqf\}p n
ANm@$xO*
首先,为了实现分页查询,我封装了一个Page类: eU"yF >6'
java代码: ?+}Su'pv}
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/*Created on 2005-4-14*/ 9R=avfI
package org.flyware.util.page; ZA=J`->k
Luao?;|U
/** :hICe+2ca
* @author Joa [Qs`@u<%
* KS_+R@3Z
*/ &N.pW=%,N
publicclass Page { ;0eVE
8~!E.u9w
/** imply if the page has previous page */ KR.;X3S}
privateboolean hasPrePage; a
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/** imply if the page has next page */ x}2nn)fdZ
privateboolean hasNextPage; SkDr4kds
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/** the number of every page */ Ug*B[q/
privateint everyPage; Jxl'!8t
WsbVO|C
/** the total page number */ hNc8uV{r=
privateint totalPage; &A
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,!>
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/** the number of current page */ 4Uny.C]
privateint currentPage; Yo %U{/e
t'K+)OK
/** the begin index of the records by the current U)dcemQY
Lv+{@)
query */ + }"+
privateint beginIndex; 2*snMA
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/** The default constructor */ +c8`N'~
public Page(){ |k~AGc
[>NMuwtG
} %Za}q]?
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/** construct the page by everyPage )B]"""J
* @param everyPage wXQu%F3
* */ ~2*LWH*@
public Page(int everyPage){ r
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this.everyPage = everyPage; -gGw_w?)(
} M2%@bETJ
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/** The whole constructor */ =*fq5v
public Page(boolean hasPrePage, boolean hasNextPage, KaEaJ
kO)Y|zQ
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int everyPage, int totalPage, X!h>13fW
int currentPage, int beginIndex){ !$98U~L
this.hasPrePage = hasPrePage; .7.1JT#@A7
this.hasNextPage = hasNextPage; J>R$K
this.everyPage = everyPage; ^.J_ w
this.totalPage = totalPage; SB%D%Zx6'%
this.currentPage = currentPage; POk5+^
this.beginIndex = beginIndex; =.s0"[%
} pwMA,X/{
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8Vd
/** <Ve0Ph K
* @return /@
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* Returns the beginIndex. W(s5mX,Kv
*/ 1*A^v
publicint getBeginIndex(){ bF9.k
return beginIndex; &Sb)a
} zgFL/a<
oY ~q^Y
/** x((u
* @param beginIndex Wm1dFf.>
* The beginIndex to set. l|+$4 Nb2
*/ O+&;,R:
publicvoid setBeginIndex(int beginIndex){ wHbmK
this.beginIndex = beginIndex; f5//?ek
} a)lCp
j f4<LmR
/** \i?bt0 bM
* @return 2RZa}
* Returns the currentPage. wMkHx3XD
*/ V|A)f@ Fs
publicint getCurrentPage(){ I3
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return currentPage; 5ppr;QaB
} -pJ\_u/&%`
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/** Yv=L'0K&
* @param currentPage :UT\L2 q=
* The currentPage to set. U
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*/ OfrzmL<K
publicvoid setCurrentPage(int currentPage){ v,opyTwG|
this.currentPage = currentPage; $<nD-4p
} O!>#q4&]
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/** mm_)=Ipj>
* @return XRV~yBIS
* Returns the everyPage. ,fiV xn Q
*/ qJ5b;=
publicint getEveryPage(){ ?o)?N8U
return everyPage; LV ]10v6
} BZv:E?1z
u~,hTY(%
/** 0B[~j7EGO
* @param everyPage V.8Vy1 $
* The everyPage to set. v~x`a0
*/ c)Ng9p
publicvoid setEveryPage(int everyPage){ 4-HBXG9#/
this.everyPage = everyPage; j0"4X
} 3 }sy{Mx%9
fP
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/** ]Ky`AG`2~
* @return B4HMs$>
* Returns the hasNextPage. TP| ogF?
*/ }@.@k6`n
publicboolean getHasNextPage(){ (mbm',%- (
return hasNextPage; Dy5&-yk
} e{5O>RO
V(;T{HW&
/** ouyZh0G
* @param hasNextPage 'h;qI&
* The hasNextPage to set. w^cQL%
*/ Mk9J~'C_
publicvoid setHasNextPage(boolean hasNextPage){ mb`h
this.hasNextPage = hasNextPage; "*HEXru#B
} ^:$ShbX"P
cxQ %tL+S&
/** XFWE^*e=B
* @return @-0mE_$[
* Returns the hasPrePage. OI0@lSAo<
*/ 'b" 7Lzp2
publicboolean getHasPrePage(){ w('}QB`xad
return hasPrePage; Za?BpV~
} >bI\pJ
`*0VN(gf'
/** UdcV<#
* @param hasPrePage P}=n^*8(I
* The hasPrePage to set. *'?V>q,
*/ 1}Guhayy
publicvoid setHasPrePage(boolean hasPrePage){ GB Vqc!d
this.hasPrePage = hasPrePage; 3xRn
} a;a1>1
}s"].Xm^2
/** C \5yo
* @return Returns the totalPage. *Cp:<Mnd
* f fI=Bt]t
*/ d%L/[.&
publicint getTotalPage(){ 2zbn8tO
return totalPage; J!|R1
} InRRcn(
=/xx:D/
/** mm*nXJ
* @param totalPage uwi.Sg11
* The totalPage to set. 4Q1R:Ra
*/ ,ExY.'%1
publicvoid setTotalPage(int totalPage){
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this.totalPage = totalPage; zgGJ<=G.
} YADXXQ"
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} O` !XW8
ml)\R L
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 o:*$G~. k
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个PageUtil,负责对Page对象进行构造: f8UJ3vB
java代码: jUZ$vyT
X,lhVT
|
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/*Created on 2005-4-14*/ <Mj{pN3
package org.flyware.util.page; NU'2QSU8
\R-'<kN.*
import org.apache.commons.logging.Log; JSylQ201
import org.apache.commons.logging.LogFactory; \|B\7a'4
~PAI0+*"q
/** WAtv4
* @author Joa 4$mtc*tzT
* Gr}NgyT<!D
*/ B+jh|@-
publicclass PageUtil { 8$ RiFD,
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privatestaticfinal Log logger = LogFactory.getLog e]dFNunFq0
Nw"?~"bo
(PageUtil.class); <gFisc/#r
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/** L&=r-\.ev
* Use the origin page to create a new page l+wfP76w
* @param page 0N]\f.=`
* @param totalRecords GJU9[
* @return q<^MC/]
*/ nW K7*
publicstatic Page createPage(Page page, int Q.3:"dT
X f;R'a,$
totalRecords){ iv],:|Mbd
return createPage(page.getEveryPage(), 2 p}I
/<-=1XJI
page.getCurrentPage(), totalRecords); zK_P3rLsS
} ,_<|e\>~
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/** rXBCM
* the basic page utils not including exception JrX. f
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handler Nq6;
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* @param everyPage !&.-{ _$
* @param currentPage P1^|r}
* @param totalRecords 3xdJ<Lrq
* @return page 5eyB\>k,
*/ QUZ+#*:s
publicstatic Page createPage(int everyPage, int \hEIQjfi
z
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currentPage, int totalRecords){ ly_8p63-
everyPage = getEveryPage(everyPage); A>mk0P)~Q
currentPage = getCurrentPage(currentPage); G^.tAO5:f
int beginIndex = getBeginIndex(everyPage, >lyE@S sA
0r i
currentPage); 8<ev5af
int totalPage = getTotalPage(everyPage, yc`3)
(c"!&&S^ =
totalRecords); ox\D04:M
boolean hasNextPage = hasNextPage(currentPage, R>&8%%#
\P"Ol\@
totalPage); y!rJ}e
boolean hasPrePage = hasPrePage(currentPage); darbL_1
w8:
returnnew Page(hasPrePage, hasNextPage, 5'V-Ly)*%
everyPage, totalPage, \MdieO*
currentPage, <Ter\o5%
<9:~u]ixt
beginIndex); 9d( M%F
} u~JR]T
a({N}ZDo
privatestaticint getEveryPage(int everyPage){ Bu?Qyz2O
return everyPage == 0 ? 10 : everyPage; E'6/@xM
} 8A::q ;
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privatestaticint getCurrentPage(int currentPage){ ,Jn` qvmi
return currentPage == 0 ? 1 : currentPage; 4M6[5RAW{
} 9`"#OQPn1
F~7TE91C
privatestaticint getBeginIndex(int everyPage, int W:9l"'
AGO"),
currentPage){ 7[K3kUm[
return(currentPage - 1) * everyPage; BJ'pe[Xa5
} N 6\Ey{
oS<GjI:
privatestaticint getTotalPage(int everyPage, int D,lY_6=
5Fj9.K~k
totalRecords){ Dbq/t^
int totalPage = 0; F0r2=f(?
X8R:9q_
if(totalRecords % everyPage == 0) agkKm?xIL
totalPage = totalRecords / everyPage; 7|_2@4-W6
else 3-1a+7fD
totalPage = totalRecords / everyPage + 1 ; !;d>}iE
rO{?.#~
return totalPage; 8Z"f"
} 5v`lCu]
_V0%JE'
privatestaticboolean hasPrePage(int currentPage){ D:z_FNN
return currentPage == 1 ? false : true; R?tjobk!
} PDz:x4A
UlNV%34"
privatestaticboolean hasNextPage(int currentPage, PyK!Cyq
Tow! 5VAM
int totalPage){ hn/yX|4c(
return currentPage == totalPage || totalPage == &@BAVc z
WU@_aw[
0 ? false : true; c5 AaUza
} Q"c/]Sk)
\i}-Y[Dg
Aho*E9VW
} \DBEs02
fOdqr
^Pu:&:ki
$d4&H/u^
^K_FGE0ec
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 h;y}g/HZ
VZ">vIRyi|
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 s1#A0%gx
bKzG5|Qu
做法如下: ![fNlG!r
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 #Ak|p#7 ^
' u;Zw%O(J
的信息,和一个结果集List: v<<ATs%w
java代码: _g( aO70Zu
wi+L4v
~3Zz.!F
/*Created on 2005-6-13*/ nD]MgT
package com.adt.bo; y65lbl%Zn
N7
hl M
import java.util.List; \7#w@3*
d<HO~+9
import org.flyware.util.page.Page; jAv3qMQA
HvKdV`bz
/** .n4{xQo,EJ
* @author Joa ^w"hA;
*/ ?~.:C'
publicclass Result { cR,'aX
'jO8C2Th%
private Page page; l]Xbd{
JRZp'Ln
private List content; D]rYg'
q8;MPXSG3
/** 4`fV_H.8
* The default constructor 4sRg+mMI
*/ }m%&|:PH
public Result(){ }A;YM1^$
super(); F< 5kcu#iL
} ;T8(byH ?
Z#(Y%6[u
/** i "X" -)#
* The constructor using fields v}D0t]
* *QIYq
* @param page I&gd"F _v}
* @param content .O(9\3q\
*/ 1LhZmv
public Result(Page page, List content){ h(J$-SUs
this.page = page; ?D_iib7
this.content = content; o:"(\$
} 1^V.L+0s]
Bg zq
/** uudd'L
* @return Returns the content. DHuvHK0#
*/ 5} ur,0{
publicList getContent(){ <sM_zoprc
return content; U>bIQk"4
} :D;pD l
q
#7Nk)<.
/** rnp; R
* @return Returns the page. /0Qo(
*/ *O @Zn
public Page getPage(){ =h
+SZXe<r
return page; }Qe(6'l_
} A:2CP&*
XqhrQU|wM
/** P>)J:.tr0
* @param content e6tU8`z
* The content to set. (: kn)
*/ Iw)m9h
public void setContent(List content){ T5e#Ll/
this.content = content; R^sgafGl=
} Z(tO]tQE
ZNk[Jn
[.
/** ,/TmTX--d
* @param page NZADHO@0
* The page to set. .f. tPm
*/ nN@
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publicvoid setPage(Page page){ *8;<w~
this.page = page; ' S,g3
} tq@)J_7|
} F2_'U' a
<exyd6iI
>SziRm>Y7
^`aw5 +S
\ Ucv<S
2. 编写业务逻辑接口,并实现它(UserManager, cXf/
\-{$IC-L
UserManagerImpl) 7bRfkKD
java代码: l,(:~KH|
4}cxSl]jf!
k\*?<g
/*Created on 2005-7-15*/ n5BD0q
package com.adt.service; t0v>J9
7r)]9_[(
import net.sf.hibernate.HibernateException; +/kOUz/]
B B'qbX3xK
import org.flyware.util.page.Page; Ie=gI+2
3fXrwmBT8
import com.adt.bo.Result; c+T`X?.j
Q8QB{*4
/** vdB2T2F
* @author Joa i^Jw`eAmT
*/ |r?0!;bN0
publicinterface UserManager { PO0Od z
m$(OQ,E
public Result listUser(Page page)throws Mw-L?j0o[k
@2d9
7.X
HibernateException; M.Tp)ig\#
DTo"{!
} -'d`(G"
+%KkzdS'
#Z
`Tk)u/
omy3<6
iyr8*L\
java代码: 99By.+~pX
O0`ofFN
/38I(0
/*Created on 2005-7-15*/ 77aUuP7Iw
package com.adt.service.impl; n_LK8
z[R
dM#L
import java.util.List; ZU.E}Rn:
6-/W4L)?>
import net.sf.hibernate.HibernateException; qvGmJN0
COw!a\Jl
import org.flyware.util.page.Page; ZF#n(Y?
import org.flyware.util.page.PageUtil; 'Z9UqEGV
a MFUj+^
import com.adt.bo.Result; n
c~JAT#'
import com.adt.dao.UserDAO; :AqtPV'
import com.adt.exception.ObjectNotFoundException; *&_cp]3-WF
import com.adt.service.UserManager; 5=p<"*zJ
)1@%!fr
/** /uDcJ1u66
* @author Joa gM]E8%;{
*/
(V'w5&f(L
publicclass UserManagerImpl implements UserManager { WS.g`%
P_8!Gp
private UserDAO userDAO; Z02EE-A
)8}k.t>'s
/** WJa7
* @param userDAO The userDAO to set. F:jtzy"
*/ wTZ(vX*mK
publicvoid setUserDAO(UserDAO userDAO){ %Ny1H/@Q1+
this.userDAO = userDAO; H_x}-
} V:P]Ved
;qbK[3.
/* (non-Javadoc) A:z
* @see com.adt.service.UserManager#listUser 52Dgul
5A|dhw
(org.flyware.util.page.Page) #Hu##x|
*/
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public Result listUser(Page page)throws ;1nXJ{jKw
Y9vi&G?Jl
HibernateException, ObjectNotFoundException { gae=+@z
int totalRecords = userDAO.getUserCount(); 5T( cy
if(totalRecords == 0) 7,Z<PE
throw new ObjectNotFoundException ZHeq)5C ;f
;/?w-)n?
("userNotExist"); 6|3 X*Orn
page = PageUtil.createPage(page, totalRecords); NRT]dYf"z
List users = userDAO.getUserByPage(page); Xppb|$qp4H
returnnew Result(page, users); nec}grA
} dhJ=+Fz"w
#^9k&t#!6
} I!1+#0SG
iTO Y
5P\A++22Y
l=Pw
yJ
,2^A<IwR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 P,WQN[(+
k W
8>VnW
询,接下来编写UserDAO的代码: di9OQ*6a7
3. UserDAO 和 UserDAOImpl: ru`U/6n
java代码: 3#]II j`\
>m<T+{`
E?KPez
/*Created on 2005-7-15*/ whP5u/857
package com.adt.dao; B<qsa QG
L{)t(H>O
import java.util.List; 1x\k:2U
2g?q4e,
import org.flyware.util.page.Page; qR?}i,_
L,nb<
import net.sf.hibernate.HibernateException; =Bm|9A1
\ )>#`X
/** IqsUtWSp
* @author Joa '!?t+L%gO
*/ >g~IP>
publicinterface UserDAO extends BaseDAO { t#y,9>6
6Bcr.`
publicList getUserByName(String name)throws }oSgx
$G }9iV7
HibernateException; h# Z,ud_
}m5()@Q}a
publicint getUserCount()throws HibernateException; Q{'4,J-w
M3F1O6=4j
publicList getUserByPage(Page page)throws K[/L!.Ag
:?FHqfN?_
HibernateException; &N6[*7
/]-yZ0hX0O
} :Mh\;e
;PU'"MeB "
_FcTY5."S
UHU ,zgM
ZUS5z+o
java代码: xaoR\H
(&r`
l&0
[UC_
/*Created on 2005-7-15*/ W(4$.uZ)
package com.adt.dao.impl; g.%} +5
s3Zt)xQ3
import java.util.List; cjO%X
.sM,U
import org.flyware.util.page.Page; x{K"z4xbI
xJU]py~o
import net.sf.hibernate.HibernateException; *_#2|96)
import net.sf.hibernate.Query; S&XlMu
6\I1J=
C
import com.adt.dao.UserDAO; 6J}Yr5oD
6vps`k$,~
/** nHq4f&(H
* @author Joa mXS]SE
*/ XK@&$~iA3
public class UserDAOImpl extends BaseDAOHibernateImpl jV%=YapF
)S`[ gK
implements UserDAO { f>4|>kS
g"kI1^[nj
/* (non-Javadoc) tu* uQ:Ipk
* @see com.adt.dao.UserDAO#getUserByName PUZcb+%]h
v'Ehr**]+
(java.lang.String) 6~2upy~e
*/ *mJ#|3I<
publicList getUserByName(String name)throws = _N[mR^
J` gG`?
HibernateException { V rx,'/IS8
String querySentence = "FROM user in class (y&sUc9
SDE$ymPx
com.adt.po.User WHERE user.name=:name"; GRkN0|ovfj
Query query = getSession().createQuery |>'N^
Meep
(querySentence); |K{d5\_
query.setParameter("name", name); c?. i;4yh
return query.list(); w%X@os}E
} U] GD6q
4pQf*l8e
/* (non-Javadoc) j|&D(]W/
* @see com.adt.dao.UserDAO#getUserCount() zy"k b
*/ Xy!NBh7I
publicint getUserCount()throws HibernateException { V.qH&FJ=l
int count = 0; ~I;x_0iY4
String querySentence = "SELECT count(*) FROM -Q
JP J.
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user in class com.adt.po.User"; =H;'.!77Hx
Query query = getSession().createQuery *)
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v@q&B|0
(querySentence); -LUZ7,!/>o
count = ((Integer)query.iterate().next |3T2}oh rr
[+R_3'aK
()).intValue(); >1Hv c7DP
return count; 8zlvzp
} G7v<Q,s
b)e;Q5Z(.
/* (non-Javadoc) %,HUn`
* @see com.adt.dao.UserDAO#getUserByPage ry=8Oq&[~
L*,h=#x(
(org.flyware.util.page.Page) H&p:
*/ Qox /abC
h
publicList getUserByPage(Page page)throws A s}L=2
dhnX\/
HibernateException { !y/e
Fx
String querySentence = "FROM user in class vazA@|^8
DC1.f(cdR
com.adt.po.User"; I%Yq86
Query query = getSession().createQuery u%yYLpaKf
qGMU>J.;c
(querySentence); Xa#.GrH6
query.setFirstResult(page.getBeginIndex()) ^--R#$X
.setMaxResults(page.getEveryPage()); cb0rkmO
return query.list(); Ay 4P_>^
} !m9hL>5vR
/!?Tv8TPp
} ;|?_C8
@{_X@Wv4iV
AzZhIhWl">
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D]}~` SO
至此,一个完整的分页程序完成。前台的只需要调用 h^Yh~84T
se2Y:v
userManager.listUser(page)即可得到一个Page对象和结果集对象 \aM-m:J
myN2G?>;
的综合体,而传入的参数page对象则可以由前台传入,如果用 Z8Y&#cB
9{j`eAUZl
webwork,甚至可以直接在配置文件中指定。 lZ[J1:%
>4kQ9lXL
下面给出一个webwork调用示例: eZ[Qhrc
java代码: r2'K'?T3
6fI2y4yEz
L?j<KW
/*Created on 2005-6-17*/ <\Y(+?+uZ
package com.adt.action.user; 41Q)w=hoN
Et(H6O8
import java.util.List; j
nSZ@u
UYJ>L
import org.apache.commons.logging.Log; +}?%w|8||s
import org.apache.commons.logging.LogFactory; Al8Dw)uG{
import org.flyware.util.page.Page; $ ~%Y}Xt*
J(/J;PW
import com.adt.bo.Result; y }R2ZO
import com.adt.service.UserService; hFr+K1
import com.opensymphony.xwork.Action; Ij.mLO]
I ZLCwaW
/** xZ`vcS(
* @author Joa bCC &5b
*/ >yP>]r+
publicclass ListUser implementsAction{ 9e>2kd
3gVU#T[[
privatestaticfinal Log logger = LogFactory.getLog @d|Sv1d%
uE (5q!/
(ListUser.class); C(B"@
Q$]1juqg
private UserService userService; GBRiU&D
/|UbYe,
private Page page; DBcR1c&<H
+4T.3Njjn
privateList users; F}meKc?a
hrzxc4,W
/* ^OIo
* (non-Javadoc) ^q/^.Gf
* ,P`G IGvkA
* @see com.opensymphony.xwork.Action#execute() ^b|? ?9&
*/ +MaEet
publicString execute()throwsException{ GeB&S!F
Result result = userService.listUser(page); ?f'`b<o
page = result.getPage(); Hmhsb2`\
users = result.getContent(); Y:m8UnT
return SUCCESS; Nb_Glf
} mrG?5.7W
w ~crj$UM
/** Ps\4k#aOv
* @return Returns the page. R_GA`U\ {
*/ -X%twy=
public Page getPage(){ N2[j By8M
return page; bDh4p]lm
} C Q iHk
S[/udA
/** US9aW)8
* @return Returns the users. 4Y1^ U{A+
*/ VbJE zl
publicList getUsers(){ <6+B;brh
return users;
ip{b*@K
} XfMUodV-OZ
AU%Yr6
/** p=x&X~
* @param page l,b,U/3R.
* The page to set. ,H/O"%OJ
*/ rOEBL|P0
publicvoid setPage(Page page){
:KG=3un]
this.page = page; tCR~z1
} r<srTHGLo
^*$!9~
/** IV':sNV
* @param users ~.U\Y
* The users to set. hH;i_("i(h
*/ f]?&R c2C
publicvoid setUsers(List users){ 06.8m;{N
this.users = users; w^nA/=;r
} `VGw5o
z%+rI
/** [U^Cz{G
* @param userService g;AW
* The userService to set. d*k5h<jM
*/ `uusUw-Gf
publicvoid setUserService(UserService userService){ z+wegF
this.userService = userService; c>/7E-T
} '3Fb[md54
} N:+EGmp
ax;<idC}
Zj ^e8u=T
\j wxW6>
p*YV*Arv
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 7MJ\*+T|03
Ujvm|ml
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 :cXN
Fu\C
X#h a*u~U
么只需要: *x p_#
java代码: D[6sy`5l
y>u|3:z
7!Im|7Ty
<?xml version="1.0"?> ttlMZLX{TJ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork W}zq9|p
3?_%|;ga
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 'BgR01w J
;KmrBNF
1.0.dtd"> (0_zp`)
IIBS:&;+-
<xwork> x*TJYST
k_?OEkgUh
<package name="user" extends="webwork- | lzcyz
a[}?!G-Wt|
interceptors"> N,VI55J:y>
En&gI`3n
<!-- The default interceptor stack name 7o!t/WEEq
+tg${3ti_
--> Rm$( X5x>o
<default-interceptor-ref >nvK{6xR:
JHZjf7g$k
name="myDefaultWebStack"/> r_tt~|s,>
4sH?85=j
<action name="listUser" <KCyXU*
ubVZEsoW?
class="com.adt.action.user.ListUser"> K g.O2F77
<param i 2uSPV!Tf
P;'ZdZ(SLu
name="page.everyPage">10</param> u:l<NWF^
<result RwrRN+&s\
z?|bs?HKS
name="success">/user/user_list.jsp</result> 8+Gwv
SDU
</action> >T0`( #Lm
#(+V&<K
</package> -*J!Ws(9
e?O$`lf
</xwork> TA:#K
-3b_}by
j:2F97
>/%XP_q%`e
-GB,g=Dk
i;|I;5tC
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 a gL@A
UFj!7gX ]
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。 DeT$4c*:[
@g" vuaG}
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 {/aHZ<I&^h
WW^+X~Y
4mX?PKvbn
[!uVo>Q4
^1_[UG
我写的一个用于分页的类,用了泛型了,hoho jPx}-_jM
{L.uLr_?e
java代码: _nX8f
&
:B7U),T
#!#s7^%K&
package com.intokr.util; K,U8 vc
37jrWe6xwp
import java.util.List; })J}7@VPO
#ZnNJ\6
/** 7i#/eRui
* 用于分页的类<br> !3DY#
* 可以用于传递查询的结果也可以用于传送查询的参数<br> +.|RH
* S9%,{y
* @version 0.01 IAe/)
* @author cheng qss)5a/x.
*/ YGc:84S
public class Paginator<E> { !<~cjgdx
privateint count = 0; // 总记录数 {5d 5Y%&
privateint p = 1; // 页编号 pe3;pRh'
privateint num = 20; // 每页的记录数 fl2XI=[v4
privateList<E> results = null; // 结果 Y
ZuA"l Y
N|Xm{@C
/** H5:f&m
* 结果总数 V s=o@
*/ ?Drq!?3PDc
publicint getCount(){ Ve)BF1YG
return count; z%lJWvaA7
} 2\T\p<_20
` QW=<Le?
publicvoid setCount(int count){ )1HWD]>4
this.count = count; WNQ<XBqAw
} kl9~obX
1
_./s[{ek
/** `c-omNu
* 本结果所在的页码,从1开始 'ShK7j$
* \[*q~95$v
* @return Returns the pageNo. ev_' .t'
*/ Q[|*P ] w
publicint getP(){ H3ovF
return p; $p$p C/:%
} s2 :Vm\
x.] tGS
/** 8gt&*;'}*D
* if(p<=0) p=1 x7G*xHJ
* #V#!@@c;?
* @param p wQ@:0GJH
*/ uxh>r2Xr=
publicvoid setP(int p){ 0\@oqw]6hv
if(p <= 0) ijzwct#.
p = 1; gxAy{
t
this.p = p; b`=g#B|
} 6qT-
rK:cUW0]X
/** -%^'x&e
* 每页记录数量 pv-c>8Wb6
*/ 1)zXv
publicint getNum(){ Q {BA`Q@V
return num; ;/JXn
} 0'YP9-C3
mo(>SnS<
/** K'
<[kh:cl
* if(num<1) num=1 _5x]BH6f
*/ Ude?[6
publicvoid setNum(int num){ Y~UAE.
if(num < 1) CXyb8z4/+
num = 1; +"=ydF.9
this.num = num; A=p'`]Yld
} oVPr`]
4neO$^i8J
/** Ek6g?rj_
* 获得总页数 c/v|e&q
*/ xk7Dx}
publicint getPageNum(){ *kYGXT,f]
return(count - 1) / num + 1; N#t`ZC&m'
} MtN!Xx
$60`Hh 4/
/** t4/ye>P &
* 获得本页的开始编号,为 (p-1)*num+1 }<l:~-y|
*/ !@N?0@$/
publicint getStart(){ uN>5Eh&=Pf
return(p - 1) * num + 1; C_8_sbZ/
} Q>rr?L`
cY kb3(
/** >!a- "
* @return Returns the results. rPGj+wL5-
*/ /@\R
publicList<E> getResults(){ BzO,(bd!PI
return results; /wt7KL-I
} \x]\W#C
PJe_qP
public void setResults(List<E> results){ L
G5_\sY!
this.results = results; Vp|?R65S*
} xSSEDfq
tpO'<b
public String toString(){ ,-8-Y>[
StringBuilder buff = new StringBuilder Q9xb7)G
3JBXGT0gJ
();
6ST(=X_C
buff.append("{"); nhjT2Sl
buff.append("count:").append(count); C])s'XTs
buff.append(",p:").append(p); N)R5#JX
buff.append(",nump:").append(num); *L$_80
buff.append(",results:").append " r o'?
1
ptyiy
(results); NX.5u8Pf
buff.append("}"); .8!\6=iJB
return buff.toString(); v:yU+s|kN
} y1Z>{SDiq
[w|Klq5
} ]W`?0VwF
,$>l[G;Bm
LCtVM70