Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 qj!eLA-aD
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %y&]'A
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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 YuQ~AE'i
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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 D'b#,a;V
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分页支持类: Dzl;-]S
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java代码: MV0Lq:# N
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package com.javaeye.common.util; x({H{'9?
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import java.util.List; rkB'Hf
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publicclass PaginationSupport { ";x+1R.d
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publicfinalstaticint PAGESIZE = 30; c3)C{9T](
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privateint pageSize = PAGESIZE; }fZ`IOf
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privateList items; :K':P5i
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privateint totalCount; >\2:\wI
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privateint[] indexes = newint[0]; UG;Y^?Ppe5
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privateint startIndex = 0; JWv{=_2w
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public PaginationSupport(List items, int >?lOE
-}^
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totalCount){ C[uOReo
setPageSize(PAGESIZE); kW@,$_cK
setTotalCount(totalCount); ~rD={&0
setItems(items); 8X$LC
setStartIndex(0); k|YWOy@D~
} nV*y`.+
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public PaginationSupport(List items, int .]x2K-Sf
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totalCount, int startIndex){ j(rL
setPageSize(PAGESIZE); '?QuJFki
setTotalCount(totalCount); ;eL9{eF
setItems(items); "*z_O
setStartIndex(startIndex); @U{<a#
} :hRs`=d"r
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public PaginationSupport(List items, int 52_#
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totalCount, int pageSize, int startIndex){ r?/A?DMe
setPageSize(pageSize); TUIk$U?/I
setTotalCount(totalCount); G:W>I=^DaR
setItems(items); 'heJ"k?
setStartIndex(startIndex); `J0i.0p
} o>Er_r
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publicList getItems(){ N K]B?
return items; V 9wI\0
} m#vL*]c}
\x{;U#B[3>
publicvoid setItems(List items){ l_rn++
this.items = items; L!Cz'm"Nl
} !v.9"!' N
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publicint getPageSize(){ . @q-B+Eg
return pageSize; ?, r~=
} FR[ B v
uX/$CM
publicvoid setPageSize(int pageSize){ OZY, @c
this.pageSize = pageSize; e({9]
} @f+8%I3D
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publicint getTotalCount(){ N2'qpxOLI
return totalCount; hU]HTX'R
} }[+!$#
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publicvoid setTotalCount(int totalCount){ !$;a[Te
if(totalCount > 0){ }A=y=+4j
this.totalCount = totalCount; b2,mCfLsv
int count = totalCount / iIT8H\e
^ KK_qC
pageSize; a ]Eg!Q
if(totalCount % pageSize > 0) V
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count++; N,dT3we
indexes = newint[count]; M 3 '$[
for(int i = 0; i < count; i++){ PNOGN|D
indexes = pageSize * oX@ya3!Pz
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i; kum#^^4G|
} kd`0E-QU
}else{
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this.totalCount = 0; 7?8wyk|x
} {5r0v#;
} >T2LEW
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publicint[] getIndexes(){ @ V08U!
return indexes; 9Jf)!o8
} i,A#&YDl
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publicvoid setIndexes(int[] indexes){ `1*nL,i
this.indexes = indexes; u]NZ`t%AP
} =*qD4qYA
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publicint getStartIndex(){ `@d<n
return startIndex; 8$s9(n-_Y
} tM-^<V&
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publicvoid setStartIndex(int startIndex){ h&.wo !
if(totalCount <= 0) {>LIMG-f
this.startIndex = 0; Pg9hW
elseif(startIndex >= totalCount) t^]$!H
this.startIndex = indexes f4-a?bp
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[indexes.length - 1]; %*aJLn+]_R
elseif(startIndex < 0) ^,l_{
this.startIndex = 0; ?Xdak|?i
else{ 9Zry]$0~R
this.startIndex = indexes !Fo*e
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[startIndex / pageSize]; Xs&TJ8a
} uw\2qU3gk
} WW+l' 6.
@`tXKP$so
publicint getNextIndex(){ ES~^M840f
int nextIndex = getStartIndex() + 21s4MagC
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pageSize; `l2O?U -@
if(nextIndex >= totalCount) ?
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return getStartIndex(); !US d9
else 4'$g(+z
return nextIndex; ?D,=37
} J
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publicint getPreviousIndex(){ k#[F`
int previousIndex = getStartIndex() - (b?{xf'G
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pageSize; 43?^7_l-
if(previousIndex < 0) H&r,FmI@
return0; 08X_}97#WF
else #HS]NA|e@
return previousIndex; y4h=Lki@
} EbeI{-'aF
[E#UGJ@
} XwV'Ha
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抽象业务类 eh1Q7~
java代码: y/e2l
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/** #r
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* Created on 2005-7-12 7+x? "4
*/ ^pM+A6
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package com.javaeye.common.business; + <,gB $j
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import java.io.Serializable; 7t,t`
import java.util.List; dU\%Cq-G)
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import org.hibernate.Criteria; VG/3xR&y
import org.hibernate.HibernateException; ikE<=:pe
import org.hibernate.Session; .jy]8S8[|%
import org.hibernate.criterion.DetachedCriteria; vI$t+m:
import org.hibernate.criterion.Projections; %| G"-%_E
import q+B&orp
!`!| Zw
org.springframework.orm.hibernate3.HibernateCallback; ~Lc066bLeq
import XqM3<~$
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org.springframework.orm.hibernate3.support.HibernateDaoS @EE."T9
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upport; olLfko4$*V
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import com.javaeye.common.util.PaginationSupport; -v6M<
x `V;Y]7'
public abstract class AbstractManager extends n$xQ[4eH)
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HibernateDaoSupport { (98Nzgxgx}
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privateboolean cacheQueries = false; Qt]Q:9I[
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privateString queryCacheRegion; jA#/Z
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publicvoid setCacheQueries(boolean 2lL,zFAq
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cacheQueries){ ~ %B<
this.cacheQueries = cacheQueries; jqr1V_3(
} ]kG(G%r|M
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publicvoid setQueryCacheRegion(String ^5r9 5
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queryCacheRegion){ ?5kHa_^
this.queryCacheRegion = =2w4C_
pm{|?R
queryCacheRegion; eAPXWWAZJ1
} ~
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publicvoid save(finalObject entity){ {BHI1Uw
getHibernateTemplate().save(entity); pRSOYTebP
} t4?DpE
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publicvoid persist(finalObject entity){ 9'hv%A:\3
getHibernateTemplate().save(entity); Z,iHy3`
} u1xSp<59C
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publicvoid update(finalObject entity){ ioPUUUb)
getHibernateTemplate().update(entity); yoAfc
} )E+'*e{cK
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publicvoid delete(finalObject entity){ #p[',$cC
getHibernateTemplate().delete(entity); ah~YeJp
} ,^icPQSwc
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publicObject load(finalClass entity, @3kKJ
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finalSerializable id){ $['Bv
return getHibernateTemplate().load <T[E=#
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(entity, id); %/updw#{B
} OT&k.!=
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publicObject get(finalClass entity, BL&LeSa
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finalSerializable id){ KD^N)&k^Kp
return getHibernateTemplate().get ZoArQ(YFy
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(entity, id); ytNO*XoR
} &>H!}"Yk
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publicList findAll(finalClass entity){ mS0udHod
return getHibernateTemplate().find("from }`+B=h-dW
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" + entity.getName()); 'w1YFdW
} h,"4SSL
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publicList findByNamedQuery(finalString tnLAJ+-M
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namedQuery){ $/nY5[
return getHibernateTemplate |^@dFOz
/> 4"~q)
().findByNamedQuery(namedQuery); "O(9 m.CZ
} *-xU2
@O[5M2|r
publicList findByNamedQuery(finalString query, N]RZbzK_5G
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finalObject parameter){ @Vu(XG
return getHibernateTemplate ~H!S,"n^,P
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().findByNamedQuery(query, parameter); rb{P :MX
} |hr]>P1
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publicList findByNamedQuery(finalString query, K(q-?n`<
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finalObject[] parameters){ >$ 2V%};
return getHibernateTemplate WVLHfkN
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().findByNamedQuery(query, parameters); tY
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} hdVdcnM
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publicList find(finalString query){ a5w:u5
return getHibernateTemplate().find 'MY/*k7:
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(query); f47M#UC
} zhf.NCSt(
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publicList find(finalString query, finalObject GaSPJt
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parameter){ 8n>9;D5n
return getHibernateTemplate().find im @h -A]0
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(query, parameter); 2+X\}s1vN
} *E{2J:`
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public PaginationSupport findPageByCriteria t#2(j1
P
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(final DetachedCriteria detachedCriteria){ x.q+uU$^
return findPageByCriteria k?'B*L_Mzv
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 4rrSb*
} [}&Sxgv
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public PaginationSupport findPageByCriteria &iV,W4
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(final DetachedCriteria detachedCriteria, finalint t]-5 ]oI
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startIndex){ ^yOZArc'r
return findPageByCriteria F;]%V%F.X
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(detachedCriteria, PaginationSupport.PAGESIZE, @*sWu_-Y%
=%/)m:f!^
startIndex); KGg3 !jY
} =kuMWaD
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public PaginationSupport findPageByCriteria rEF0oJ.
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(final DetachedCriteria detachedCriteria, finalint Hhh0T>gi
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pageSize,
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finalint startIndex){ R2
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return(PaginationSupport) Bi{$@n&?f
0L/n ?bf
getHibernateTemplate().execute(new HibernateCallback(){ CvD"sHVq%
publicObject doInHibernate q|),`.eh\
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(Session session)throws HibernateException { eow'K
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Criteria criteria = }I>tO9M
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detachedCriteria.getExecutableCriteria(session); 0vw4?>Jf@
int totalCount = VTH>
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((Integer) criteria.setProjection(Projections.rowCount m|G'K[8
T~='5iy|
()).uniqueResult()).intValue(); }B1!gz$YNO
criteria.setProjection (I./ Uu%
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(null); mrjswF27$o
List items = g?ULWeZg5
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criteria.setFirstResult(startIndex).setMaxResults ^cuc.g)c$?
d}4Y(
(pageSize).list(); ZEx}$<)_
PaginationSupport ps = % S os
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new PaginationSupport(items, totalCount, pageSize, sL$:"=
7K98#;a)5
startIndex); zld#qG6
return ps; VF ys.=
} H7DJ~z~J
}, true); mVpMh#zw
} #}y2)g
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public List findAllByCriteria(final sdo[D
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DetachedCriteria detachedCriteria){ ]@u6HH~^
return(List) getHibernateTemplate +csi[c)3E
#%h-[/
().execute(new HibernateCallback(){ #e$5d>j(
publicObject doInHibernate *vwbgJG! *
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(Session session)throws HibernateException { >: g3k
Criteria criteria = 6l:qD` _
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detachedCriteria.getExecutableCriteria(session); :Nz2z[W$
return criteria.list(); =7m)sxj]w
} ~o~!+`@q
}, true); gK'1ZLdZ2
} OD!& .%
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public int getCountByCriteria(final CTZ8Da^
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DetachedCriteria detachedCriteria){ AiO$<CS
Integer count = (Integer) ] [p>Y>:b-
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getHibernateTemplate().execute(new HibernateCallback(){ 1 P!Yxeh
publicObject doInHibernate m()RU"WY
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(Session session)throws HibernateException { ,tu.2VQc@
Criteria criteria = |$
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detachedCriteria.getExecutableCriteria(session); ) iN/ua
return YOmM=X+'H
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criteria.setProjection(Projections.rowCount KJaXg;,H
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()).uniqueResult(); !`Hd-&}bYz
} f@|A[>"V
}, true); J`].:IOh
return count.intValue(); "ozr+:#\
} ^Xq 6:
} eEv@}1~
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用户在web层构造查询条件detachedCriteria,和可选的 :fZ}o|t7
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 gf
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PaginationSupport的实例ps。 BMG3|N^
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ps.getItems()得到已分页好的结果集 &;[Io
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 ~O
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ps.getStartIndex()当前分页索引 "8x8UgG
ps.getNextIndex()下一页索引 Uyg5i[&X@
ps.getPreviousIndex()上一页索引 !h23cj+V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 4C61GB?Vy
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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 jHE}qE~>5
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一下代码重构了。 mD$A4Y-'p
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我把原本我的做法也提供出来供大家讨论吧: bnq;)>&
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首先,为了实现分页查询,我封装了一个Page类: a!7A_q8M
java代码: pfA|I*`XV
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/*Created on 2005-4-14*/ la0BiLzb]
package org.flyware.util.page; ([T>.s
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/** lT(WD}OS
* @author Joa V@e?#iz
* u~7hWiY<2
*/ H]{v;;'~
publicclass Page { C*)3e*T*
GP!?^r:en
/** imply if the page has previous page */ ^84G%)`&
privateboolean hasPrePage; rb5~XnJk
J%v=yBC2
/** imply if the page has next page */ +%T\`6
privateboolean hasNextPage;
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/** the number of every page */ 0%&1\rm+j
privateint everyPage; @5=oeOg36
d6}r#\
/** the total page number */ tZ:_ag)o
privateint totalPage; ^ =bu(L
:mh_G
/** the number of current page */ m4hX 'F
privateint currentPage; E4`N-3
]/[FR 5>
/** the begin index of the records by the current \r;#g{
_
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query */ L[oui,}_
privateint beginIndex; D.B.7-_8
s@&`f{
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/** The default constructor */ y I HXg#
public Page(){ AK,J 7
4IB9,?p
} lGPUIoUo
Bn=by{i
/** construct the page by everyPage f2Klt6"9
* @param everyPage 1n >X[!
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* */ ZXqSH${Tp
public Page(int everyPage){ B8.Pn
this.everyPage = everyPage; ]
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} 6}gls}[0{e
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/** The whole constructor */ bU>U14ix<
public Page(boolean hasPrePage, boolean hasNextPage, *g:4e3Iy
Fsmycr!R
E
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int everyPage, int totalPage, >BR(Wd.
int currentPage, int beginIndex){ oX#Q<2z*
this.hasPrePage = hasPrePage; fM]+SMZy
this.hasNextPage = hasNextPage; @K\~O__
this.everyPage = everyPage; q}`${3qQ3
this.totalPage = totalPage; nW PF6V>
this.currentPage = currentPage; _GXk0Ia3`
this.beginIndex = beginIndex; j~2{lCT
} 5gb|w\N>
v~f HYa>
/** A;;fACF8e
* @return ciFmaM.
* Returns the beginIndex. q!{y&.&\
*/ 35Ij
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publicint getBeginIndex(){ 54gBJEhg
return beginIndex; $*^kY;
} :#LLo}LKp
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/** %824Cqdc
* @param beginIndex 6*PYFf`
* The beginIndex to set. B8nf,dj?X
*/ 4^p5&5F
publicvoid setBeginIndex(int beginIndex){ bx#>BK!
this.beginIndex = beginIndex; F |d\k Q
} +DW~BS3
j-4VB_N@
/** AYt%`Y.!
* @return 3C?f(J}
* Returns the currentPage. xHUsFms
*/ `n#H5Oyn
publicint getCurrentPage(){ Pj#<K%Bz
return currentPage; NTdixfR
} (_niMQtF}
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/** ]9YJ,d@J
* @param currentPage $yn];0$J
* The currentPage to set. )<oJnxe]
*/ 3)F|*F3R
publicvoid setCurrentPage(int currentPage){ =!kk|_0%E
this.currentPage = currentPage; M`. tf_x
} !S^AgZ~
T m_bz&Q
/** yWg@v+
* @return T_s_p
* Returns the everyPage. Y#!UPhg<
*/ 4E;VM{
publicint getEveryPage(){ I!^;8Pg
return everyPage; !9u|fnC9
} J4QXz[dG
931bA&SL=/
/** aH 4c02s$
* @param everyPage E[2m&3&
* The everyPage to set. N^#ZJoR
*/ M}`B{]lLz
publicvoid setEveryPage(int everyPage){ 98j>1"8
this.everyPage = everyPage; ~T ]m>A!
} 88VZR&v
$}<PL}+
/** =@m &s^R
* @return {v=T [D
* Returns the hasNextPage. vX{J' H]u
*/ $&y%=-] |
publicboolean getHasNextPage(){ T?:Rdo!:u
return hasNextPage; u5O+1sZ"6
} GS0;bI4ay
o}$XH,-9&
/** aK&b{d
* @param hasNextPage UM!ENI|
* The hasNextPage to set. VbJiZw(aR
*/ ~o82uw?
publicvoid setHasNextPage(boolean hasNextPage){ ~c8?>oN(
this.hasNextPage = hasNextPage; @E^~$-J5j
} ~;QvWS
NV)!7~r}:
/** :?k>HQe
* @return &)8:h+&Z
* Returns the hasPrePage. *'OxAfa#x
*/ u\E?Y[1
publicboolean getHasPrePage(){ Usr@uI#{J
return hasPrePage; 2VF%@p
} B268e
k>F'ypm
/** bBu,#Mc
* @param hasPrePage @PN#p"KaT
* The hasPrePage to set. -u&6X,Oq\u
*/ 9:fOYT$8
publicvoid setHasPrePage(boolean hasPrePage){ (hTCK8HK
this.hasPrePage = hasPrePage; x4g3rmp
} NS9B[*"Jl
wHsYF`
/** <:(6EKJAq}
* @return Returns the totalPage. dA-2%uJ
* nIAx2dh?
*/ 8yRJD[/S
publicint getTotalPage(){ m$`RcwO
return totalPage; 6Se?sHC>
} fXXr+Mor
*"R|4"uy
/** YsG%6&zEq
* @param totalPage sC27FVwo
* The totalPage to set. ;>506jZ
*/ XOxr?NPQ^
publicvoid setTotalPage(int totalPage){ e`@ # *}A
this.totalPage = totalPage; T:t]"d}}
} 4FEk5D
?f#y1m
} 7q?9Tj3
F|F]970
AcS|c:3MUy
O>qll6]{@
`D>S;[~S7
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 ~Cl){8o
JCz@s~f\y
个PageUtil,负责对Page对象进行构造: F
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java代码: .EpV;xq}
flk=>h|
rJPb 3F
/*Created on 2005-4-14*/ K2he4<
package org.flyware.util.page; 6^%UU
o%
LL] zT H0
import org.apache.commons.logging.Log; qgE 73.!`6
import org.apache.commons.logging.LogFactory; /nyUG^5#{
4S,`bnmB
/** ^cV;~&|.Xk
* @author Joa $>*3/H
* if}-_E<F
*/ wkP#Z"A0~
publicclass PageUtil { (2$(
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>QA uEM
privatestaticfinal Log logger = LogFactory.getLog aki_RG>U'
HKF H/eV
(PageUtil.class); Kpb#K[(]&
=fu
:@+
/** w<zIAQN
* Use the origin page to create a new page Ks=>K(V6
* @param page h lkn%
* @param totalRecords W;_nK4$%'
* @return q/4YS0CqE
*/ |\QgX%
publicstatic Page createPage(Page page, int Rz(QC\(
-9"['-WH,
totalRecords){ 'I_Qb$
return createPage(page.getEveryPage(), eL^.,H0
NxjB/N
page.getCurrentPage(), totalRecords); e&7JpT
} /[O(ea$U
K|Ld,bq
/** kspTp>~
* the basic page utils not including exception =jSb'Vu|
thV>j9'
handler Sczc5FG
* @param everyPage UQ'\7OS
* @param currentPage #~SP)Ukp
* @param totalRecords 1=#q5dZ]
* @return page /3;4#:Kkw
*/ 7.C;NT
publicstatic Page createPage(int everyPage, int lCAIK
yMyE s 8
currentPage, int totalRecords){ 7G.#O}).b
everyPage = getEveryPage(everyPage); *&?c(JU;<
currentPage = getCurrentPage(currentPage); HU%o6c w
int beginIndex = getBeginIndex(everyPage, /b]oa!
vLR~'"`F
currentPage); q2. XoCf
int totalPage = getTotalPage(everyPage, gT$Ju88
<.pU,T/
totalRecords); eAX
)^q
boolean hasNextPage = hasNextPage(currentPage, [PQ?#:r
,
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totalPage); ]d,S749(s
boolean hasPrePage = hasPrePage(currentPage); >2~+.WePu
uvtF_P/
returnnew Page(hasPrePage, hasNextPage, .{ 44a$)
everyPage, totalPage, [!} :KD2yX
currentPage, U"q/rcA
NLS%S q
beginIndex); /3eKN
} 8CnRi
s_x:T<]
privatestaticint getEveryPage(int everyPage){ @7n/Q(
return everyPage == 0 ? 10 : everyPage; @kk4]:,w
} ojQI7 Uhw
HFwN
privatestaticint getCurrentPage(int currentPage){ BDVHol*g
return currentPage == 0 ? 1 : currentPage; m-H-6`]
} 9;Itqe{8w
Gqcq,_?gt
privatestaticint getBeginIndex(int everyPage, int !,[C]Q1
qtiz a~u
currentPage){ 4!+pc-}-
return(currentPage - 1) * everyPage; _/Gczy4)#
} V6t,BJjS
`kbSu}
privatestaticint getTotalPage(int everyPage, int 6T+FH;h
NG
totalRecords){ 4AG\[f
8q
int totalPage = 0; a;QMAd!
rA2g&
if(totalRecords % everyPage == 0) 6b%WHLUeT
totalPage = totalRecords / everyPage; ^xh}I5
else .mDM[e@'
totalPage = totalRecords / everyPage + 1 ; /I)yU>o
Q2zjZC*'%
return totalPage; }
@K FB
} hF@Gn/
x%+aKZ(m)
privatestaticboolean hasPrePage(int currentPage){ *g y{]
return currentPage == 1 ? false : true; $ "E).j
} 8wVY0oRnU
w=LP"bqlI
privatestaticboolean hasNextPage(int currentPage, MS0Fl|YA
0$7s^?G0
int totalPage){ COTp
return currentPage == totalPage || totalPage == 8<.C3m
6h
F;gx%[$GX
0 ? false : true; KN7^:cC
} K$ M^gh0
qw@puw@D
.pfP7weQ
} 2zVJ vn7
1AG=%F|.
,hq)1u
AZa6Cw
F%i^XA]a*
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。 |tv"B@`
mN!lo;m5
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 @O@GRq&V
jeGj<m
做法如下: ]wKz E4Z/
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "I=\[l8t
t5'V6nv
的信息,和一个结果集List: AtF3%Zv2
java代码: pGf@z:^{*-
{e+-vl
v2H#=E4cZ#
/*Created on 2005-6-13*/ zX0mdx<|<
package com.adt.bo; uiJS8(Cb
g.'yZvaP
import java.util.List;
fv`O4
taFn![}/!g
import org.flyware.util.page.Page; 87:!C5e}
5B&;uY
/** C?i >.t
* @author Joa D\[h:8k
*/ v^ zu:Z*
publicclass Result { oP!;\a( SL
-O&CI)`;B
private Page page; E2cB U{x
&Y
4F!Rb
private List content; ^5A
t?I8
:WSDf VX
/** DyQM>xw)t
* The default constructor 1Wm)rXW[x
*/ *+uHQgn(
public Result(){ 3&6#F"7
super(); 1gmt2>#v%
} 1j:Wh
*^RmjW1I
/** v.:3"<ur}
* The constructor using fields TQ`Rk;0R
* LJOr!rWi
* @param page UTf9S>HS
* @param content #]#sGmW/L
*/ "TUe%o
public Result(Page page, List content){ Kx=4~
this.page = page; G!Um,U/g
this.content = content; 7ULqo>j
} -K
rxMi
[Z~ 2
/** ithewup
* @return Returns the content. LwhyE:1
*/ ]~6_ WE8L
publicList getContent(){ $Bj;D=d@V
return content; -s|}Rh?Y
}
qNm$Fx
FL8g5I
/** - !>}_AH
* @return Returns the page. OvUI@,Ef
*/ 'yV?*a
public Page getPage(){ "Ae@lINn[y
return page;
1~l
I8
} ^-rfvc
sf]s",t~J
/** \EKU*5\Hp>
* @param content CBDG./
* The content to set. #fJ] o_
*/ rQEyD
public void setContent(List content){ 5w\fSY
this.content = content; 52b*[tZ
} K{ \;2M
`E!N9qI?t$
/** "Vr[4&`
* @param page 7lS#f1E
* The page to set. p/2jh&
*/ 9_QP !,
publicvoid setPage(Page page){ &f7fK|}
this.page = page; V\})3i8
} "dROb}szn
}
bu=?N
QT9n,lX
w,O,W[C
=7m}yDs6$
Q 2A7mGN
2. 编写业务逻辑接口,并实现它(UserManager, i~3u>CT
N<QjdD&
UserManagerImpl) DhX#E&
java代码: ,o^y`l
*loOiM\5a
-F=v6N {
/*Created on 2005-7-15*/ 6<'rG''
package com.adt.service; "Tm[t?FMbe
,^gyH
\
import net.sf.hibernate.HibernateException; R |f~>JUF
PG8^.)]M
import org.flyware.util.page.Page; M\Gdn92pd
k{V E1@
import com.adt.bo.Result; (ewe"N+
kPQtQh]y%
/** }U
SC1J
* @author Joa K9vIm4::d$
*/
*]h`KxuO
publicinterface UserManager { }hYZ"
A~
$''9K
public Result listUser(Page page)throws D;I6Q1I
0W3i()
HibernateException; >(y<0
50
A^bbid
} T \CCF
>Bs#Xb_B]
YPzU-:3
;SwMu@tg
DAwqo.m
java代码: gPu2G/Y
?x^z]N|P
~V/?H!r'{}
/*Created on 2005-7-15*/ 2kv7UU#q2
package com.adt.service.impl; `)qVF,Z}
DfV~!bY
import java.util.List; oG7q_4+&
tX!nsm1
import net.sf.hibernate.HibernateException; *xE,sj+(
>|6iR%"f#
import org.flyware.util.page.Page; .))v0
import org.flyware.util.page.PageUtil; +525{Tj
@Kf_z5tm:
import com.adt.bo.Result; be e5
import com.adt.dao.UserDAO; c*`>9mv
import com.adt.exception.ObjectNotFoundException; goJ|oi
import com.adt.service.UserManager; =?h~.lo
7 Sa1;%R
/** }|B=h
* @author Joa BSq)RV/3
*/ +n })Y
publicclass UserManagerImpl implements UserManager { kQaSbpNmH
?:|-Dq,
private UserDAO userDAO; |v[ Rp=?]
q~L^au8
/** p'sc0@}_O
* @param userDAO The userDAO to set. @$"L:1_
*/ )HD`O~M>
publicvoid setUserDAO(UserDAO userDAO){ w'X]M#Q><
this.userDAO = userDAO; oo=#XZkk
} QRLJ_W^&u
/%A;mlf{
/* (non-Javadoc) M(d6Z2ibh
* @see com.adt.service.UserManager#listUser (~)%Fo9X"
YUQtMf9
(org.flyware.util.page.Page) mR8W]'gl.L
*/ z4@k$
L8
public Result listUser(Page page)throws ;pD)m/$h`
q!f1~ aG
HibernateException, ObjectNotFoundException { s4 %(>Q
int totalRecords = userDAO.getUserCount(); rdnRBFt
if(totalRecords == 0) Xnuzr"4u
throw new ObjectNotFoundException /U6%%%-D`
mp~{W
("userNotExist"); fbFX4?-
page = PageUtil.createPage(page, totalRecords); Qp2I[Ioz3
List users = userDAO.getUserByPage(page); 9_fePS|Z4
returnnew Result(page, users); ]NhS=3*i+
} aS|wpm)K>8
* MM[u75
} }X;U|]d
OzT#1T1'c
Dml*T(WM>
XJ!(F#zc
iqhOi|!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 G5D2oQa=8
CK_(b"
询,接下来编写UserDAO的代码: /D_+{dtE
3. UserDAO 和 UserDAOImpl: `]$?uQ
java代码: M+wt__vHf
#a| L3zR5v
-ng=l;
/*Created on 2005-7-15*/ 19(Dj&x
package com.adt.dao; >x3ug]Bu
wA`"\MWm
import java.util.List; 4$,,Ppn
@c'|Iqy`
import org.flyware.util.page.Page; 0aR,H[r[?
JK#vkCkyM
import net.sf.hibernate.HibernateException; Ufo>|A6;$
5FC4@Ms`
/** qQ7w&9r.M
* @author Joa 1\dn1Hh
*/ w:o-klKXY
publicinterface UserDAO extends BaseDAO { iRG?# "
Je4Z(kj 0
publicList getUserByName(String name)throws ^*R(!P^
9umGIQHnil
HibernateException; rOD1_X-
_SZ5P>GIU
publicint getUserCount()throws HibernateException; Io2mWvu?5
E?PGu!&u
publicList getUserByPage(Page page)throws .Qt4&B
PiLJZBUv
HibernateException; 5/m$)wE
Uz%Z&K
} $R8w+ Id
^TXf sQs
-Uo?WXP]B'
o@lWBfB*%e
5 waw`F
java代码: ,]Zp+>{
}8'&r(cN4
>+cVs:
/*Created on 2005-7-15*/ <Wl(9$
package com.adt.dao.impl; ,/&Zw01dGN
d0er^ ~
import java.util.List; %u p}p/?
;52'}%5
import org.flyware.util.page.Page; V'Qn sI
km:nE: |
import net.sf.hibernate.HibernateException; H L<s@kEZ
import net.sf.hibernate.Query; v7trr W}
K&A;Z>l,v5
import com.adt.dao.UserDAO; 77gysd\(
xPmN},i'R$
/** BOf1J1
* @author Joa Q
|i9aE
*/ `GQ{*_-
public class UserDAOImpl extends BaseDAOHibernateImpl RE46k`44
6R}j-1
<n
implements UserDAO { Z&!!]"I
j?(!^ _!m
/* (non-Javadoc) 0?bA$y
* @see com.adt.dao.UserDAO#getUserByName v.Ogf5
Zu<]bv
(java.lang.String) s[3fqdLP&
*/ XOb}<y)r~
publicList getUserByName(String name)throws /jD-\,:L}
i4Z4xTn
HibernateException { Mxz,wfaH>
String querySentence = "FROM user in class L x|',6S
d-!<C7O}
com.adt.po.User WHERE user.name=:name"; =N.!k Vkl
Query query = getSession().createQuery ^!:"Q3
MWWu@SY
(querySentence); h:qHR]
8dZ
query.setParameter("name", name); Edt}",s7
return query.list(); $v;dV@tB
} P-z`c\Rt
!FG%2L4?,5
/* (non-Javadoc) yOHXY&
* @see com.adt.dao.UserDAO#getUserCount() oJ;rc{n-
*/ 0.(<'!"y
publicint getUserCount()throws HibernateException { Z/ bB
h
int count = 0; utO.WfWP
String querySentence = "SELECT count(*) FROM V+B71\x<
KI&:9j+M)
user in class com.adt.po.User"; *FgJ|y6gk
Query query = getSession().createQuery CyM}Hc&w
%l9$a`&
(querySentence);
7
Yv!N
count = ((Integer)query.iterate().next mv
Ov<x;l
z[!x:# q8`
()).intValue(); EZr6oO@Nc
return count; 9q4_j
} zjM/M
!G=>ve
/* (non-Javadoc) |KG&HNfP-
* @see com.adt.dao.UserDAO#getUserByPage IS_Su;w>4
8:g!w:$x
(org.flyware.util.page.Page) -wr(vE,
*/ FRyPeZR
publicList getUserByPage(Page page)throws -Wo15O"
]EL\)xCr
HibernateException { RtF8A5ys
String querySentence = "FROM user in class -Wjh* *
K} x/ BhE+
com.adt.po.User"; G!-J$@P
Query query = getSession().createQuery 13f<0wg
lH1g[ ))
(querySentence); .gD km^
query.setFirstResult(page.getBeginIndex()) Enj_tJs
.setMaxResults(page.getEveryPage()); .|]IwyD
&
return query.list(); ! *a[jhx
} [e4![G&y`
6$e]i|e
} (r F?If
wly>H]i'
8$~3r a
jUY+3"?
M9"Sgb`g
至此,一个完整的分页程序完成。前台的只需要调用 3VP $x@AV
J|j;g!fK
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?JqjYI{$
E$S`6+x`:a
的综合体,而传入的参数page对象则可以由前台传入,如果用 |`]oc,1h@
|cTpw1%I~
webwork,甚至可以直接在配置文件中指定。 G=$}5; t
YOw?'+8
下面给出一个webwork调用示例: :EB,{|m
java代码: dB)[O9K)
YN#XmX%
:WX0,-Gn
/*Created on 2005-6-17*/ !C`20,U
package com.adt.action.user; ;QPy:x3
nPf'ee
import java.util.List; )Qr6/c8}
euZ(}+N&
import org.apache.commons.logging.Log; ?`. XK}
import org.apache.commons.logging.LogFactory; fOBN=y6x
import org.flyware.util.page.Page; w6U
@tW
nLd~2qBuv
import com.adt.bo.Result; &z ksRX
import com.adt.service.UserService; 5P\N"Yjx'
import com.opensymphony.xwork.Action; _;G=G5r
iwo$\
/** ~07RFR
* @author Joa NhDA7z`b'J
*/ 4K,''7N3
publicclass ListUser implementsAction{ #WEq-0L
kIM
C~Z
privatestaticfinal Log logger = LogFactory.getLog 9.-47|-9C
oc;VIK)g]c
(ListUser.class); H ja^edLj
q)oN2-
private UserService userService; cHEz{'1m
>Z"9rF2SW
private Page page; +S0u=u65
,>w}xWSYpG
privateList users; pzSqbgfrQ
+ (=I8s/
/* 1*c>I@I;
* (non-Javadoc) |Mlh;
* A\g%
* @see com.opensymphony.xwork.Action#execute() )[
b#g(Y(
*/ @LC~*_y
publicString execute()throwsException{ UT;4U;a,m
Result result = userService.listUser(page); ~,Mr0
page = result.getPage(); xppkLoPK
users = result.getContent(); ; +9(;
return SUCCESS; EE9vk*[@C
} =LqL@5Xr
`oPLl0
/** aH^{Vv$]M@
* @return Returns the page. tQf!|]#J
*/ j@SYXKL~
public Page getPage(){ 4tnjXP8
return page; `:3&@.{T(
} {g@A>
C2.W[T
/** jMqx
* @return Returns the users. qAORWc
*/ *+W6 P.K
publicList getUsers(){ 8 >dq=0:
return users; q xSs
~Qc
} OaNc9c"
<vLdBfw&N
/** i :EO(`
* @param page c
_p[yS
* The page to set. ooDdV
>
*/ A`Q
>h{
publicvoid setPage(Page page){ } bCK
this.page = page; uDI}R]8~
} .xo_}Vw
59~FpjJ
/** r
hZQQOQ
* @param users gE1|lY$NL
* The users to set. e
SK((T
*/ n5 >B LtY
publicvoid setUsers(List users){ 9PCa*,
this.users = users; q
/:T1a7!
} >*{:l,LH
|yU3Kt
/** +/(|?7i@
* @param userService A{M+vsL
* The userService to set. IuDT=A
*/ &p)@8HY
publicvoid setUserService(UserService userService){ 1oB$u!6P
this.userService = userService; LVoyA/F
} $)l2G;&
} Pm;I3r=R\
u(8~4P0w
F6DxvyANr
{9 Db9K^
*afejjW[
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, A ^-Z)0:
yW{mK
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 *b:u*`@
e$H|MdYIA
么只需要: q _19&;&
java代码: YK7 \D:
@OY1`EuO
V*>73I
<?xml version="1.0"?> i'Wcf1I-=
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 89db5Dx
LH,]vuXh
1.0//EN" "http://www.opensymphony.com/xwork/xwork- <3)|44.o&
T^d#hl.U
1.0.dtd"> 2'|XtSj
,YQ=Zk)w
<xwork> $vW^n4!
0c`sb+?
<package name="user" extends="webwork- fJvr+4i4k
-*r [
interceptors"> HE@-uh
$]nVr(OZ_
<!-- The default interceptor stack name avmcGyL
]&' jP
--> ZMP?'0h=
<default-interceptor-ref 3Hy%SN(
L,E-z_<p
name="myDefaultWebStack"/> 5d> nIKW
@Jkui
<action name="listUser" E7k-pquvE
5Ws5X_?d
class="com.adt.action.user.ListUser"> AL(n*,
<param i[o&z$JO
sN"p5p
name="page.everyPage">10</param> /4(Z`e;0
<result h\/^Aa0
/L)?> tg
name="success">/user/user_list.jsp</result> qwL0~I
</action> Nz3zsP$
sWp{Y.
</package> f%vHx,
=_K%$y*
</xwork> IES41y<
8y-e+
jkZ_c!
,:c:6Y^
gkSGRshf
LQ~LB'L
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Z`^
K%P=
&
8ccrw
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 Xs{/}wc.q;
+dDJes!]
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 <m~T>Ql1
MP6 \r
@=02
yBr$ 0$
Q~x*bMb.
我写的一个用于分页的类,用了泛型了,hoho j@%K*Gb`
A"Tc^Ij
java代码: (r.$%[,.<
58M'r{8_
I[tAT[ <
package com.intokr.util; >&*6Fqd
0Ei\VVK>
import java.util.List; V;M3z9xd
l
:f9Ih
/** 7~nIaT
* 用于分页的类<br> ['/;'NhdlY
* 可以用于传递查询的结果也可以用于传送查询的参数<br> VC/R)%@%
* hdo+Qezu:
* @version 0.01 }".\
4B$n
* @author cheng tpN]evp|
*/ B)(p9]q
public class Paginator<E> { nwZ[Ygl|
privateint count = 0; // 总记录数 c2tEz&=G
privateint p = 1; // 页编号 L-^# 02
privateint num = 20; // 每页的记录数 Bq~AU#
privateList<E> results = null; // 结果 \W3+VG2cA
s#'|{
/** 43UJ#rF
* 结果总数 bx+(.F
*/ NTXws4'D
publicint getCount(){ *uk\O]
return count; wJ;9),fL
} J`U$b+q6
=g{_^^n
publicvoid setCount(int count){ F2Nb5WT
this.count = count; #R~">g:w
} g_3rEvf"4
O JZ!|J8?
/** pkrl@jv >
* 本结果所在的页码,从1开始 f]@[4<N y
* !Ei Ze.K
* @return Returns the pageNo. AlPL;^Y_l
*/ O^QR;<t'
publicint getP(){ P^'>dOI0w
return p; \#h})`
} `DU'wB
Bbn832iMUY
/** ~$ cm9>
* if(p<=0) p=1 A"P\4
* X=S}WKu
* @param p )?=
kb
*/ {Sd@u$&
publicvoid setP(int p){ mSVX4XW<
if(p <= 0) &F@tmM~
p = 1; '=@-aVp
this.p = p; _*OaiEL+:
} -jcrXskb&N
"6|'&6&
/** 7v4-hfN
* 每页记录数量 -y7l?N5F>
*/ ex;Yn{4
publicint getNum(){ s+OvS9et_
return num; LaAgoarN
} .HH,l
S4@117z5
/** ~|$) 1
* if(num<1) num=1 MSxU>FX0
*/ xc3Ov9`8%
publicvoid setNum(int num){ %j
9vX$Hj
if(num < 1) W#oEF/G
num = 1; bUipp\[aV
this.num = num; HbJadOK
} 8yJk81
gY
#/&q
/** )VSGqYr#
* 获得总页数 _zVbqRHlw
*/ 3!ajvSOI9j
publicint getPageNum(){ bOnukbJ
return(count - 1) / num + 1; DI2S
%Nl
} DcFV^8O&
A ydy=sj
/** O(c4iWm
* 获得本页的开始编号,为 (p-1)*num+1 {<Xo,U7y
*/ .q|xMS}4
publicint getStart(){ !T&u2=`D
return(p - 1) * num + 1; b{yH4)O
} V.E.~<7D\
N?`GZ+5
/** //4p1^%
* @return Returns the results. MOH,'@&6^
*/ do:RPZ!
publicList<E> getResults(){ 5BGv^Qb_2
return results; <try%p|f
} 0zq\ j
7\Yq]:;O
public void setResults(List<E> results){ &`\kb2uep
this.results = results; ;Kq<',u~
} n=#[Mi $Y
+(=[M]5#n
public String toString(){ S4uR\|
StringBuilder buff = new StringBuilder m8j#{[NE
:jN;l
(); 9Rt(G_'
buff.append("{"); ua. 6?W)
buff.append("count:").append(count); H~1?MAX
buff.append(",p:").append(p); \C'I l
w
buff.append(",nump:").append(num); 16d{IGMz
buff.append(",results:").append '
m#Ymp
'&o>
%V
(results);
ZeDDH
buff.append("}"); )9;kzp/
return buff.toString(); 2Xk1AS
} YRT}fd>R&
sjVl/t`l
} !UPAEA
aV0;WH_3
5Dh&ez`oR'