Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 TZ+ p6M8G
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 8]Tv1Wc
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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 Ix6\5}.c 9
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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 8>t,n,k
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分页支持类: ccrWk*tr
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java代码: ol*,&C:{
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package com.javaeye.common.util; Uns%6o
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import java.util.List; PMpq>$6b7
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publicclass PaginationSupport { W} i6{Vh
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publicfinalstaticint PAGESIZE = 30; tc0;Ake-&
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privateint pageSize = PAGESIZE; ":8\2Qp
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privateList items; ^8;MY5Wbs
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privateint totalCount; @<{%r
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privateint[] indexes = newint[0]; ^hiY6N &
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privateint startIndex = 0; Q(]m1\a
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public PaginationSupport(List items, int ~t~[@2?WG
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totalCount){ jwT` Z
setPageSize(PAGESIZE); gDVsi
setTotalCount(totalCount); .@E5dw5
setItems(items); DPjs?M<
setStartIndex(0); 953qz]Q8
} vII{i
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public PaginationSupport(List items, int @k&6\1/U
\^*:1=|7u]
totalCount, int startIndex){ $j.;$~F
setPageSize(PAGESIZE); 1oej<67PdJ
setTotalCount(totalCount); I09 W=
setItems(items); O{_t*sO9q*
setStartIndex(startIndex); vt{[_L(h
} 8Y.qP"s
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public PaginationSupport(List items, int JFVx&
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totalCount, int pageSize, int startIndex){ lG\uJxV
setPageSize(pageSize); D,}bTwRb-
setTotalCount(totalCount); &liON1GLM
setItems(items); O hk\P;}
setStartIndex(startIndex); LDc EjFK(
} NgDhdOB
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publicList getItems(){ SK\@w9#&$
return items; @W>@6E
} hK3-j;eg
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publicvoid setItems(List items){ B18BwY
this.items = items; Kf:!tRE
} ZKXE7p
i
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publicint getPageSize(){ q$:7j5E
return pageSize; 5_aj]"x
} +PjTT6
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publicvoid setPageSize(int pageSize){ |+q_kx@?l
this.pageSize = pageSize; =U3S"W %
} =O }^2OARo
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publicint getTotalCount(){ D<6$@ZJ
return totalCount; reN\|?0{
} Xe%J{
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publicvoid setTotalCount(int totalCount){ ]ub"OsXC
if(totalCount > 0){ C8|V?bL
this.totalCount = totalCount; X\h.@+f=
int count = totalCount / YCD|lL#
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pageSize; t2o{=!$WH
if(totalCount % pageSize > 0) Oj c Tu
count++; + +}!Gfc?s
indexes = newint[count]; $Y|OGZH8E
for(int i = 0; i < count; i++){ @&}}tALi
indexes = pageSize * 09-8Xzz
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} fEZuv?@
}else{ <?KPyg2
this.totalCount = 0; e"t0 rScA
} eP @#I^_
} LL#REK|lm8
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publicint[] getIndexes(){ 4u:SE
return indexes; !i;6!w
} ;d6Dm)/(
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publicvoid setIndexes(int[] indexes){ r%.k,FzGZY
this.indexes = indexes; 0V1GX~2
} r@4A%ql<
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publicint getStartIndex(){ 2t\0vV2)/O
return startIndex; [Arf!W-QG
} a<<4gXx
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publicvoid setStartIndex(int startIndex){ |fgUW.
if(totalCount <= 0) Y)1/fEM
this.startIndex = 0; )%K<pIk
elseif(startIndex >= totalCount) !zX()V
this.startIndex = indexes L+8ar9es
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[indexes.length - 1]; L]kBY2c
elseif(startIndex < 0) |Mb{0mKb
this.startIndex = 0; dEJqgp}\p
else{ {$^'oRk
this.startIndex = indexes ?P'$Vxl
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[startIndex / pageSize]; msmW2Zc
} |T|m5V'l
} mXRkR.zu+
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publicint getNextIndex(){ AM}2=Ip
int nextIndex = getStartIndex() + ;ek*2Lh
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pageSize; X<%D@$
if(nextIndex >= totalCount) Oh! {E5!)
return getStartIndex(); [[$CtqLg
else gHe:o`
return nextIndex; \V>5)Rn
} N{v)pu.
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publicint getPreviousIndex(){ TF8#I28AD
int previousIndex = getStartIndex() - ^p3GT6
j9+4},>>CU
pageSize; B->AY.&j
if(previousIndex < 0) 4C*ywP
return0; (.4lsKN<
else Tvx1+0Z%z
return previousIndex; aD: #AmbJ
} >&(#p@#
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} :A zT=^S
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抽象业务类 GKt."[seV
java代码: 36=aahXd\
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/** ]DNPG"
* Created on 2005-7-12 ]}v]j`9m%
*/ bIU.C|h@
package com.javaeye.common.business; p[Po*c.b
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import java.io.Serializable; Cy;UyZ
import java.util.List; q}LDFsU
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import org.hibernate.Criteria; >bW=oTFz
import org.hibernate.HibernateException; T-] {gc
import org.hibernate.Session; ?Lg(,-:
import org.hibernate.criterion.DetachedCriteria; joe)b
import org.hibernate.criterion.Projections; d/; tq
import cw<IL
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org.springframework.orm.hibernate3.HibernateCallback; 3x[Cpg,
import t7]j6>MK3q
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org.springframework.orm.hibernate3.support.HibernateDaoS <X)\P}"L4
/*#o1W?wQZ
upport; ^FLs_=E
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import com.javaeye.common.util.PaginationSupport; 2^o7 ^S
es)^^kGj6f
public abstract class AbstractManager extends tkj-.~@g0'
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HibernateDaoSupport { ~Gfytn9x.;
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privateboolean cacheQueries = false; t%}<S~"
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privateString queryCacheRegion; 7P<VtS
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publicvoid setCacheQueries(boolean O*~,L6# }
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cacheQueries){ D;R~!3f./b
this.cacheQueries = cacheQueries; Y9^l|,bm5
} kE:[6reG
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publicvoid setQueryCacheRegion(String e0P[,e*0
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queryCacheRegion){ 5 bI:xL}
this.queryCacheRegion = K%J?'-
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queryCacheRegion; Yz/Blh%V
} ^\ [p6>
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publicvoid save(finalObject entity){ [.}qi[=n
getHibernateTemplate().save(entity); 1$0Kvvg[
} +pR,BjY
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publicvoid persist(finalObject entity){ =ANr|d
getHibernateTemplate().save(entity); F!X0Wo=
} @;4;72@O
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publicvoid update(finalObject entity){ Ih.+-!w
getHibernateTemplate().update(entity); AX v
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} uyYV_Q0~;
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publicvoid delete(finalObject entity){ M{jXo%C
getHibernateTemplate().delete(entity); uMQI Aapb
} dL0Q8d\^T
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publicObject load(finalClass entity, B/4M;G~
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finalSerializable id){ `]5qIKopL
return getHibernateTemplate().load $)#orZtzr
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(entity, id); hju^x8
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} vFk@
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publicObject get(finalClass entity, > Z+*tq
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finalSerializable id){ 3'uXU<W!
return getHibernateTemplate().get pbx*Y`v
pq)
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(entity, id); =2 HY]H
} ,?8a3%
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publicList findAll(finalClass entity){ '7'/+G'~&
return getHibernateTemplate().find("from jF?0,g
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" + entity.getName()); tNY;wl:wp
} XY'=_5t
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publicList findByNamedQuery(finalString O<$w-(
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namedQuery){ .:?v;rYk{
return getHibernateTemplate E>_Rsw *
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().findByNamedQuery(namedQuery); ZD&F ,2v
} $V87=_}
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publicList findByNamedQuery(finalString query,
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finalObject parameter){ J,W$\V]p
return getHibernateTemplate $+WXM$N
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().findByNamedQuery(query, parameter); s&E,$|80
} }uIQ@f`
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publicList findByNamedQuery(finalString query, XCI
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finalObject[] parameters){ A$wC!P|;
return getHibernateTemplate =aVvv+T
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().findByNamedQuery(query, parameters); *P' X[z
} p7YYAh@x\
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publicList find(finalString query){ lj]M 1zEz&
return getHibernateTemplate().find +t,b/K(?]
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(query); 4pL'c@'
} :P-H8*n""
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publicList find(finalString query, finalObject 3V]dl)en%
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parameter){ OmBM)g
return getHibernateTemplate().find q_[y|ETJ]
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(query, parameter); (3N/DY1/
} 5J`w8[;
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public PaginationSupport findPageByCriteria '
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(final DetachedCriteria detachedCriteria){ a~yiLq
return findPageByCriteria Kz;Ar&^`N
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); h?TIxo:6/
} 807+|Ol[
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public PaginationSupport findPageByCriteria '_?Z{|
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(final DetachedCriteria detachedCriteria, finalint 8~T}BC
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startIndex){ `RY}g;
return findPageByCriteria N-l`U(Z~P
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(detachedCriteria, PaginationSupport.PAGESIZE, L$Z!
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startIndex); rT R$\ [C
} \Hb!<mrp
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public PaginationSupport findPageByCriteria jIaaNO)
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(final DetachedCriteria detachedCriteria, finalint N%Bl+7,q
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pageSize, h_t`)]-
finalint startIndex){ 3fLdceT
return(PaginationSupport) % (h6m${j
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getHibernateTemplate().execute(new HibernateCallback(){ Gw)y<h
publicObject doInHibernate W)1nc"WqY
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(Session session)throws HibernateException { JX'}+.\
Criteria criteria = kVLZdXn,q2
| K|AUI
detachedCriteria.getExecutableCriteria(session); e_!h>=$%8
int totalCount = Jm ,:6T
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((Integer) criteria.setProjection(Projections.rowCount `0ZH=*P
9L7z<ntn
()).uniqueResult()).intValue(); qdQ4%,E[
criteria.setProjection ?n<F?~
"6]oi*_8
(null); {#+K+!SvDX
List items = G9xl-ag+z
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criteria.setFirstResult(startIndex).setMaxResults "`K_5"F
#reR<qp&]
(pageSize).list(); n$ByTmKxv
PaginationSupport ps = =9,mt
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new PaginationSupport(items, totalCount, pageSize, Jb{g{a/
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startIndex); 9V)cf
return ps; )*%uG{h
} T.De1Q|
}, true); ~7aD#`amU
} )Fd)YJVR
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public List findAllByCriteria(final oBmv^=cH
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DetachedCriteria detachedCriteria){ idBdaZg
return(List) getHibernateTemplate n jd2
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().execute(new HibernateCallback(){ k4&adX@Y
publicObject doInHibernate lYe2;bu
@}jg5}
(Session session)throws HibernateException { yq, qS0Fo
Criteria criteria = &T-:`(
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detachedCriteria.getExecutableCriteria(session); xe OfofC(l
return criteria.list(); @/aJi6d"^E
} bHq.3;
}, true); ,h5 FX^
} >WO;q
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public int getCountByCriteria(final }#Up:o]A!
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DetachedCriteria detachedCriteria){ yo5-x"ze
Integer count = (Integer) 0<A*I{,4L
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getHibernateTemplate().execute(new HibernateCallback(){ (|O(BxS
publicObject doInHibernate s4 ,`
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(Session session)throws HibernateException { J%Y-3{TQK
Criteria criteria = W SvhC
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detachedCriteria.getExecutableCriteria(session); v3~`1MM
return &%3}'&EBv
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criteria.setProjection(Projections.rowCount M+-odLltw
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()).uniqueResult(); xxGQXW
} \Ogs]4
}, true); fZs}u<3Q)
return count.intValue(); !j6CvclT
} FBi&MZ`
} n%2c<@p#
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用户在web层构造查询条件detachedCriteria,和可选的 (<`>B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *ax&}AHK[/
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PaginationSupport的实例ps。 ZDK+>^A)
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ps.getItems()得到已分页好的结果集 CW@EQ3y0
ps.getIndexes()得到分页索引的数组 ;[C_ho
ps.getTotalCount()得到总结果数 KVC18"|f
ps.getStartIndex()当前分页索引 aB&a#^5CI
ps.getNextIndex()下一页索引 gW G>}M@
ps.getPreviousIndex()上一页索引 \= 6dF,V
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 tTq2AR|
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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 %Q93n {?
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一下代码重构了。 bT:;^eG"
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我把原本我的做法也提供出来供大家讨论吧: z4[8*}
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首先,为了实现分页查询,我封装了一个Page类: K?S5C8
java代码: /u'V>=D;f
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/*Created on 2005-4-14*/ &
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package org.flyware.util.page; 1VXn`O?LW
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/** UN6nh T
* @author Joa ;|vn;s/
* GQ9H>Ssz
*/ )"bP]t^_
publicclass Page { B%co`0$
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/** imply if the page has previous page */ qaBL
privateboolean hasPrePage; DRu#vC
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/** imply if the page has next page */ 4n\O6$&.x
privateboolean hasNextPage; 8(@(G_skp
=6,w~|W
/** the number of every page */ DoEN`K\U
privateint everyPage; Cm6%wAzC
M;X}v#l|XI
/** the total page number */ VPDd*32HC
privateint totalPage; G/Yqvu,2!
#
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/** the number of current page */ .gwT?O,
privateint currentPage; om0g'Qa
>`
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/** the begin index of the records by the current H3|x
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query */ Kb#Z(C9
privateint beginIndex; /n 1H;~f]
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/** The default constructor */ uWr vkLGN
public Page(){ Qvhy9Cr;
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} N9AM% H$7
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/** construct the page by everyPage !X{>?.@~
* @param everyPage 4q`e<!MP)q
* */ ,6T3:qkkvF
public Page(int everyPage){ ET=-r
this.everyPage = everyPage; {r[g.@
} li)shp)
$-BM`Zt0;
/** The whole constructor */ }FAO.
public Page(boolean hasPrePage, boolean hasNextPage, D]5cijO6
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#7,;/rtO7
int everyPage, int totalPage, ujoJ6UOG
int currentPage, int beginIndex){ F@@6D0\X?
this.hasPrePage = hasPrePage; @O&; %IZMY
this.hasNextPage = hasNextPage; G+W0X
this.everyPage = everyPage; "D/\&1.&
this.totalPage = totalPage; ~`CWpc:
this.currentPage = currentPage; 4wx_@8
this.beginIndex = beginIndex; e_t""h4D
} af;~<oa
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/** QR{pph*zn-
* @return p V`)
* Returns the beginIndex. %b3s|o3An
*/ JQ"w{O
publicint getBeginIndex(){ L=-v>YL+
return beginIndex; K Fn[
} |7E1yu
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/** @6z]Xb
* @param beginIndex 6#Afj0
* The beginIndex to set. {);<2]o| 6
*/ ~e<h2/Xc
publicvoid setBeginIndex(int beginIndex){ C\5"Kb
this.beginIndex = beginIndex; : x@j)&
} ZE0D=
V.kRV{43
/** GMYfcZ/,K
* @return i.6+CA
* Returns the currentPage. ~{gV`nm=J
*/ ^Y+P(o$HM
publicint getCurrentPage(){ vvcA-k?
return currentPage; zQyt 1&!
} j21nh >d
Pa\"l'!>^
/** .7M:AS>
* @param currentPage u(g0Ob
* The currentPage to set. t73" d#+
*/ M"<B@p]rk:
publicvoid setCurrentPage(int currentPage){ u8i!Fxu
this.currentPage = currentPage; ^|ln q.j
} 4 .d~u@=
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/** N3QDPQ
* @return f"g-Hbl5
* Returns the everyPage. t7qY!S (
*/ 8UN7(J
publicint getEveryPage(){ I`FqZw
return everyPage; QcG-/_,'}
} }2~$"L,_
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/** "3X~BdH&J
* @param everyPage "jMSF@lr
* The everyPage to set. k_hs g6Ur.
*/ Q"=$.M~
publicvoid setEveryPage(int everyPage){ a!Ht81gj
this.everyPage = everyPage; 7,&M6<~
} { x/~gp
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/** rq_0"A
* @return [,As;a*o
* Returns the hasNextPage. r*XEne
*/ i*ErxWzu
publicboolean getHasNextPage(){ 68-2EWq
return hasNextPage; l#k&&rI5x.
} 4<Q^/-W
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/** ;<)<4N"
* @param hasNextPage )$7-CNWr~
* The hasNextPage to set. Emx`+9
*/ KBkS>0;X
publicvoid setHasNextPage(boolean hasNextPage){ ^4 ?LQ[t'
this.hasNextPage = hasNextPage; '\I!RAZ
} urA
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/** &R;Cm]jt
* @return K \_JG$(9
* Returns the hasPrePage. lD\vq 2
*/ r\DA&b
publicboolean getHasPrePage(){ ^L"ENsOs
return hasPrePage; =UMqa;\K
} 0s'H(qE,_
vo JmNH
/** 1&Ruz[F5
* @param hasPrePage 7\nR'MOZ
* The hasPrePage to set.
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=^
*/ o"-*,:Qe
publicvoid setHasPrePage(boolean hasPrePage){ pZaOd;t
this.hasPrePage = hasPrePage; nb ,+!)+
} %AnqT|\#,
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/** ;>Q.r{P
* @return Returns the totalPage. 8-cCWoc
* ZI/Ia$O
*/ 0\2#(^
publicint getTotalPage(){ ~|5B
return totalPage; #<EMG|&(
} >0Gdxj]\
=!{
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/** ;'~GuZ#I
* @param totalPage 9E-]S'Z
* The totalPage to set. r;
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*/ [OK(
publicvoid setTotalPage(int totalPage){ J.^%VnrFO9
this.totalPage = totalPage; _m2p>(N|
} AIX?840V
l11+sqg
} $>=?'wr
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 B(B77SOb
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个PageUtil,负责对Page对象进行构造: gOL-b9W
java代码: |QcE5UC
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LOX}
/*Created on 2005-4-14*/ KKJ)BG?qZ
package org.flyware.util.page; CE;J`;
CP"
import org.apache.commons.logging.Log; vS'l@`Eg]
import org.apache.commons.logging.LogFactory; t`oH7)nut
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/** *j"u~ NF
* @author Joa FQW{c3%qZ
* |fhYft
*/ }{S
f*
publicclass PageUtil { yirQ
9w:9XziT
privatestaticfinal Log logger = LogFactory.getLog bj$VYS"kY
1Q>D^yPI[
(PageUtil.class); Y `ySNC
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/** "s.]amC
* Use the origin page to create a new page tX@G`Mr(
* @param page R7Z7o4jg
* @param totalRecords "B3&v%b
* @return \~~y1.,U.
*/ sm9/sX!
publicstatic Page createPage(Page page, int +fRABY5C
Wi%e9r{hU
totalRecords){ rS&"UH?c7
return createPage(page.getEveryPage(), `m7w%J.> n
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page.getCurrentPage(), totalRecords); Iq["(!7E5
} SL ) ope
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/** H2
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* the basic page utils not including exception +u\kTn
8LH\a.>
handler )Lb?ZXT3
* @param everyPage 2vh@KnNU
* @param currentPage "f |xIK`c
* @param totalRecords %]1.)j
* @return page vtu!* 7m
*/ Y6w7sr_R
publicstatic Page createPage(int everyPage, int Wv7hY"
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currentPage, int totalRecords){ 7*I:cga
everyPage = getEveryPage(everyPage); )p!.V(,
currentPage = getCurrentPage(currentPage); =Owr
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int beginIndex = getBeginIndex(everyPage, v-ZTl4j$
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currentPage); CEHtr90P
int totalPage = getTotalPage(everyPage, B+r$_L&I
E hw2o-s^
totalRecords); !LAC_b
boolean hasNextPage = hasNextPage(currentPage, A-*y[/
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totalPage); #_?m.~`g[
boolean hasPrePage = hasPrePage(currentPage); tQ7:4._
%|AXVv7IN>
returnnew Page(hasPrePage, hasNextPage, VV$4NV&`Q
everyPage, totalPage, EV.F/Wh
currentPage, zz**HwRt
[
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beginIndex); &w'1
} e gdbv
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privatestaticint getEveryPage(int everyPage){ Ouos f1
return everyPage == 0 ? 10 : everyPage; \S]` { kY,
} YU ,fx<c
] =*G[
privatestaticint getCurrentPage(int currentPage){ wT>~7$=L{
return currentPage == 0 ? 1 : currentPage; U!O"f
} K'\Jnn
T]UrKj/iF
privatestaticint getBeginIndex(int everyPage, int ,+GS.]8<
j{&$_
currentPage){ f~t5[D(\Q,
return(currentPage - 1) * everyPage; me ,lE-
} $eiW2@
yE{\]j|Zf
privatestaticint getTotalPage(int everyPage, int OuMj%I
dC(5I{I|
totalRecords){ E/@
int totalPage = 0; ?DgeKA"A
V:<Z
if(totalRecords % everyPage == 0) >QSlH]M
totalPage = totalRecords / everyPage; >1 %|T
else twP%+/g]<
totalPage = totalRecords / everyPage + 1 ; }Yargj_Gn
\]|(w*C
return totalPage; 0`KR8# A@
} !D|c2
6]NaP_\0
privatestaticboolean hasPrePage(int currentPage){ rd1EA|T
return currentPage == 1 ? false : true; 3-v&ktD&N'
} dJ.up*aR
P{+,?X\
privatestaticboolean hasNextPage(int currentPage, Mi)h<lY
8DGPA
int totalPage){ r)|6H"n#]S
return currentPage == totalPage || totalPage == 8e"MP\0V
1YScZ
0 ? false : true; noZ!j>f{@l
} SQT]'
l1%ubu
MGLcM&oR
} rH$M6S
/*e6('9s
~?zu5,vb
Aaug0X
S{jm4LZ
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;Iax \rQ
.2V?G]u
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ?h)T\z
ok1-`c P
做法如下: !:c_i,N
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >udu~
7G=Q9^J.H
的信息,和一个结果集List: .L9n
java代码: &$yDnSt\
N{#9gr3zi
yA~1$sA1
/*Created on 2005-6-13*/ ZxAk
package com.adt.bo; nhy:5eSK
#H;1)G(/
import java.util.List; m+QZ|
cJ#n<Rsz
import org.flyware.util.page.Page; *r)dtI*
I{i6e'.jP
/** }poLHS/
* @author Joa 5}TTf2&Xo#
*/ "Pl.G[Buc-
publicclass Result { U;#G$
($Q|9>5,
private Page page; [&pMU)
HdRwDW@7=
private List content; #xh
M&X
cb }OjM F
/** j[4l'8Ek
* The default constructor Ui'*$W]v
*/ yp]z@SYA@
public Result(){ g>QN9v})
super(); w[g`)8Ib
} e)$a ;6
_wUg+Xs]
/** K0|:+s@u
* The constructor using fields Ctbc!<@o
* DD}YbuO7
* @param page "a-;?S&
* @param content #giH`|#d
*/ pP%9MSCi
public Result(Page page, List content){ <07]w$m/
this.page = page; Mtc -
this.content = content; ]fSpG\yU
} 63QF1*gPH
Q@[ (0R1
/** U~w8yMxX
* @return Returns the content. KGGJ\r6
*/ $!^C|,CS
publicList getContent(){ +5Ju `Z
return content; NH4T*R)Vz
} U6#9W}CE
%WPyc%I
/** ;Kh?iqn^
* @return Returns the page. qfqL"G
*/ n7.85p@ua
public Page getPage(){ vs@u*4.Ut<
return page; <8^ws90Y
} 5p ,HkV
F{Oaxn
/** W4(GI]`_+
* @param content 6Zx5^f(qd
* The content to set. ~-UO^$M-
*/ h:i FLS f
public void setContent(List content){ &t6:1 T
this.content = content; h-\Ov{~
} vlFq-W!
X|C=Q
/** >z73uKA(
* @param page R&Ss ET.
* The page to set. <{i1/"k?X
*/ Js^(mRv=
publicvoid setPage(Page page){ Zr(eH2}0D
this.page = page; eQ*zi9na
} "q
KVGd
} rDGrq9
JAy-N bb\
o.V
JnrJ
n. vrq-
:3{n(~
2. 编写业务逻辑接口,并实现它(UserManager, F`1J&S;C
39L_O RMH
UserManagerImpl) qMw_`dC
java代码: In8{7&iVO
9CAu0N5<
7rG+)kHG
/*Created on 2005-7-15*/ iUs_)1
package com.adt.service; Y$9x!kV
"\u<\CL
import net.sf.hibernate.HibernateException; Y@7n>U
DB}v..
import org.flyware.util.page.Page; *BvdL:t
^$]iUb{\
import com.adt.bo.Result; #J t1AV
K+~1z>&
/** RKp9[^/?
* @author Joa ihekON":
*/ D=K{(0{"/,
publicinterface UserManager { G
@EEh.s9
v`S ;.iD
public Result listUser(Page page)throws O$N;a9g
;.^!
7j
HibernateException; (}s& 84!
% bKy
} B>c2 *+Bk
Q(O0z3 b
Tp.:2[
_#
cM vlk
KD]`pqN9
java代码: U;0:@.q
db@^CS[P
0O>M/ *W
/*Created on 2005-7-15*/ QEMT'Cs
package com.adt.service.impl; *j=58d`n
Ti7
@{7>
import java.util.List; PPh<9$1\g
=R ZPDu
import net.sf.hibernate.HibernateException; ZXXJ!9-&+J
HU$]o N
import org.flyware.util.page.Page; F'CJN$6Mw/
import org.flyware.util.page.PageUtil; uG/'9C6Z
&[SFl{fx>-
import com.adt.bo.Result; brG!TJ
import com.adt.dao.UserDAO; KT+{-"4-
import com.adt.exception.ObjectNotFoundException; 0/1=2E^,
import com.adt.service.UserManager; %gj7KF
RJKi98xwJ
/** rITA-W O
* @author Joa /qMiv7m~Q
*/ `jyyRwSoe
publicclass UserManagerImpl implements UserManager { Db !8N
w`fbUh6/
private UserDAO userDAO; O*Y ? :
t
R0mkEM
/** *.KVrS<B1
* @param userDAO The userDAO to set. eI-SWwmv/u
*/ #f%fY%5q
publicvoid setUserDAO(UserDAO userDAO){ FA := )
this.userDAO = userDAO; 947;6a%$
} vif)g6,
Bsha)<
/* (non-Javadoc) @/:7G.
* @see com.adt.service.UserManager#listUser r^H,H'BohJ
/^v!B`A@
(org.flyware.util.page.Page) unKl5A[h
*/ !\'H{,G
public Result listUser(Page page)throws :{VXDT"
y4$$*oai&
HibernateException, ObjectNotFoundException { Xfbr;Jt"<
int totalRecords = userDAO.getUserCount(); B/o8r4[80
if(totalRecords == 0) C+"c^9[
throw new ObjectNotFoundException )y i~p
G!wb|-4<$
("userNotExist"); 6b$C/
page = PageUtil.createPage(page, totalRecords); `)4v Q+A>
List users = userDAO.getUserByPage(page); Dr[;\/|#
returnnew Result(page, users); a)c;z@r
} =f [/Pv
.lM]>y)
} Zu~w:uNmU
U_;="y
-7'|&zP
bfm+!9=9S
0pG +yec
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 N%ccy?B
o`!#io
询,接下来编写UserDAO的代码: |"S#uJW
3. UserDAO 和 UserDAOImpl: >Vg [A
java代码: fM|s,'Q1x
A?$-Uqb"
kjB'WzZ8
/*Created on 2005-7-15*/ Qe-Pg^PS]
package com.adt.dao; D~Ef%!&
KUK.;gG*Z
import java.util.List; 4_sJ0 =z-
]9)iBvQlj
import org.flyware.util.page.Page; #sBL E
6 eu7&Kj'
import net.sf.hibernate.HibernateException; 0rz1b6F5,
JtsXMZz
/** l'@!'
* @author Joa B3D}'<
*/ VBS}2>p
publicinterface UserDAO extends BaseDAO { MkjB4:"
"'@D\e}
publicList getUserByName(String name)throws 7Z~JuTIZ
*9xxX,QT8Q
HibernateException; RgJbM\`}?
q5JQx**g
publicint getUserCount()throws HibernateException; fA]sPh4Uag
Q672iR\#)
publicList getUserByPage(Page page)throws Bha("kG
9v;HE{>
HibernateException; L N.:>,
6xwjKh:9
} e$WAf`*
6({)O1Z
[]aw;\7}Y
%<+uJ'pj
3$q#^UvD
java代码: _ `O",Ff
4b((,u$
@"A
5yD5
/*Created on 2005-7-15*/ WT")tjVKA
package com.adt.dao.impl; /$]S'[5uF
{dh,sbl
import java.util.List; TwVkI<e0s?
8_G6X\q};
import org.flyware.util.page.Page; 5uahfJk
%'_:#!9
import net.sf.hibernate.HibernateException; ; %(sbA
import net.sf.hibernate.Query; HRrR"b9:
FG+pR8aA$
import com.adt.dao.UserDAO; y N9~/g
MRK=\qjD
/** upk+L^
* @author Joa FN<>L0
*/ /W-ges
public class UserDAOImpl extends BaseDAOHibernateImpl S[yrGX8lu
VpAwvMw
implements UserDAO { @ext6cFe3<
r&B0-7r
/* (non-Javadoc) 6}Tftw$0z
* @see com.adt.dao.UserDAO#getUserByName Lu:*nJ%1[
.0RQbc9
(java.lang.String) W)J5[p?
*/ P0(LdZH6u
publicList getUserByName(String name)throws @1&"S7@}u
?u?mSO/
HibernateException { iAk.pH]a
String querySentence = "FROM user in class B(vCi^
I{>Z0+
com.adt.po.User WHERE user.name=:name"; n1JV)4Mv
Query query = getSession().createQuery %72(gR2Wa2
8 >LDo"<
(querySentence); 3**t'iWQ
query.setParameter("name", name); G4~@
return query.list(); U1Fo #L
} >i >|]
8#tuB8>
/* (non-Javadoc) oF]]Pl{W
* @see com.adt.dao.UserDAO#getUserCount() I=
<eCv
*/ ;|oft-y
publicint getUserCount()throws HibernateException { QdcuV\B}
int count = 0; &4} =@'G@
String querySentence = "SELECT count(*) FROM ot2zY
dWAz
6__!M
user in class com.adt.po.User"; vqQ)Pu?T
Query query = getSession().createQuery :[(%4se
v0! 1W
(querySentence); \}W3\To_
count = ((Integer)query.iterate().next T?d}IDv1
#_aq@)Fd
()).intValue(); U{Oo@ztT
return count; PN8#T:E
} 7NWkN7:B
_F`JFMS
/* (non-Javadoc) [kqtkgK$j2
* @see com.adt.dao.UserDAO#getUserByPage c/^jD5U7
$RRX-
(org.flyware.util.page.Page) }N(gP_?n
*/ %Cqp88]
publicList getUserByPage(Page page)throws Oso**WUOZ&
Qc?W;Q+
HibernateException { p%sizn
String querySentence = "FROM user in class %kop's&?C
\xl$z*zI
com.adt.po.User"; O $e"3^Pa
Query query = getSession().createQuery ",vK~m2W_
z80FMulO
(querySentence); Ee7+ob
query.setFirstResult(page.getBeginIndex()) vk
X+{n
.setMaxResults(page.getEveryPage()); 0L8fpGJ
return query.list(); k+?gWZ\
} GiM-8y~
l4r>#n\yj
} ];6955I!
0asP,)i
{D..(f1*u
Ri_2@U-
~CV.Ci.dG
至此,一个完整的分页程序完成。前台的只需要调用 ru 9@|FgAE
(>ze{T|
userManager.listUser(page)即可得到一个Page对象和结果集对象 F<6(Hw#>
}v|_]
的综合体,而传入的参数page对象则可以由前台传入,如果用 +_pfBJ_$%
XR7v\rd
webwork,甚至可以直接在配置文件中指定。 rFzj\%xa[
tN\I2wm
下面给出一个webwork调用示例: o@.{|j
java代码: w}OBp^V^
cUG^^3!
F@q9UlfB-
/*Created on 2005-6-17*/ /Mw;oP{&b
package com.adt.action.user; :2==7u7v?
Keo<#Cc?
import java.util.List; hF@%k
;I
zng.(]U/?H
import org.apache.commons.logging.Log; aZ_3@I{d`
import org.apache.commons.logging.LogFactory; f sh9-iY8e
import org.flyware.util.page.Page; lkJxb~S
C"**>OGe
import com.adt.bo.Result; +jwk4BU
import com.adt.service.UserService; `|Di?4+6%
import com.opensymphony.xwork.Action; \ HUDZ2 s
j[A(@w"
/** ]4[%Sv6]G
* @author Joa 2#^g] o-N
*/ _z BfNz9D
publicclass ListUser implementsAction{ Q
Kr/
h0k?(O
privatestaticfinal Log logger = LogFactory.getLog ;Bz|hB{
R?:Q=7K
(ListUser.class); fi*b]a\'
<
B]qqqP
private UserService userService; u*=^>LD
eCN:
private Page page; M$@~|pQ<
)LKJfoo
PY
privateList users; 1~~GF_l?
a$Ud"
/* 5j ]!r
* (non-Javadoc) pQ0*)}l,
* U*Y]cohh
* @see com.opensymphony.xwork.Action#execute() 2/V%jS[4#y
*/ *aM7d>nG5
publicString execute()throwsException{ Zv9JkY=+@
Result result = userService.listUser(page); 0%L:jq{5
page = result.getPage(); @M<qz\
[
users = result.getContent(); t'At9<ib
return SUCCESS; y6d!?M(0U
} 579D
\WC,iA%Y
/** LkzA_|8:D
* @return Returns the page. e>e${\=,
*/ XK/l1E3N
public Page getPage(){ j;y(to-e>D
return page; 62'9lriQ
} JmR2skoV,
>I~Q[
/** Yu)GV7\2
* @return Returns the users. JHm Pa
*/ 8g_kZ^<[
publicList getUsers(){ 0<@['W}G
return users; e/+.^ '{
} vI(LIfe;
*@#Gc%mGu
/** &gS-.{w "
* @param page VUUnB<j
* The page to set. c\rP
-"C
*/ }UGSE2^1
publicvoid setPage(Page page){ )Z/w|5<
this.page = page;
qCrpc=
} &53,8r
T>(X`(
/** v8 =#1YB;
* @param users ,GVX1B?
* The users to set. l%mp49<
*/ >S }X)4
publicvoid setUsers(List users){ #Ox@[Z1I
this.users = users; Pb T2-
F_
} $X Uck[
V1d#7rP
/** U.~G{H`G,u
* @param userService s
Y1@~ v
* The userService to set. s=jH1^
*/ ZaY|v-
publicvoid setUserService(UserService userService){ <h#W*a
this.userService = userService; l(Hz9
} # =y)Wuo=
} 7z3tDE[#
sDg1nKw(
nTGf
F?a
63,r
-UidU+ES;
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 0!%G#~th
}[!=O+gO
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 0%&}w UjV
A*+gWn,4Y_
么只需要: (c}!gjm
java代码: 4Lk<5Ho
J^#g?RHN>m
\DE,
,
<?xml version="1.0"?> 2eRk_j]
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork fHZ9wK>
i qxMTH#!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- xa]yq%
yId1J
1.0.dtd"> _fn7-&6
PeiRe
<xwork> >JA-G@3i
5-fASN.Lx
<package name="user" extends="webwork- :!CnGKgt
PY '^:0
interceptors"> 8,h!&9
R%}<z*~NE@
<!-- The default interceptor stack name n
ei0LAD
/=za
m3kd
--> K0v S
<default-interceptor-ref Ici4y*`M
7;TMxO=bra
name="myDefaultWebStack"/> Q{=r9&&
*wJz0ex7R/
<action name="listUser" {)b
U&*%KPy`
class="com.adt.action.user.ListUser"> 9L-jlAo<
<param VR"le&'z"
\X(*JNQ
name="page.everyPage">10</param> SzeY?04zj:
<result q4!\^HwQ
vY.VFEP/
name="success">/user/user_list.jsp</result> dJrUcZBr
</action> CflyK@
6Ktq7'Z@
</package> +{;wOQ.
1D[>oK\
</xwork> &CXk=Wj
t&x\@p9
3jW&S
G"(aoy,
co
W<^t2 j'
*6u2c%^
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 znWB.H
K7{B!kX4k
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 \BfMCA/
+CSv@ />3
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )+,h}XqlX
B9
?58v&
O.y ?q
NB^Al/V@
\pI {b9
我写的一个用于分页的类,用了泛型了,hoho nW\W<[O9
"|&3z/AUh
java代码: oXk6,b"
jvR(e"
v/~&n
package com.intokr.util; 8[AU`F8W
An?#B4:
import java.util.List; S"^'ksL\
jd5kkX8=
/** sieC7raO
* 用于分页的类<br> 9qGba=}Ey
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :,$"Gk
* E^{!B]/oP
* @version 0.01 *+6iXMwe
* @author cheng Zi\ex\ )5
*/ >y#qn9rV1
public class Paginator<E> { pih 0ME}z
privateint count = 0; // 总记录数 r.Z g<T
privateint p = 1; // 页编号 :?ZrD,D
privateint num = 20; // 每页的记录数 I!kR:Z
privateList<E> results = null; // 结果 RZnmia
]D,_<Kk
/** u+6D|
* 结果总数 bV'r9&[_6
*/ 6'uCwAQU
publicint getCount(){ 7l*vmF6Z
return count; U6H3T0#
} NZ8X@|N
L"S2+F)n
publicvoid setCount(int count){ Tz9 (</y
this.count = count; pJl/d;Cyrb
} Q3bU"f
WL,2<[)Ew
/** c8Q2H
* 本结果所在的页码,从1开始 w<]-~`K
* 1!U:M8T|
* @return Returns the pageNo. jyyig%
*/ b9T6JS j
publicint getP(){ DYIp2-K
return p; hz<TjWXv'
} ;P8%yf
`YZl2c<w*
/** *$;Zk!sEF
* if(p<=0) p=1 %2\Pe 2Z
* K/}x'*=
* @param p {^;7DV:
*/ z_KCG2=5
publicvoid setP(int p){ DMp@B]>
if(p <= 0) 3'A0{(b
p = 1; fJk'5kv
this.p = p; Sj/v:
} F9las#\J
s?9Y3]&+&M
/** #k>A,
* 每页记录数量 L>7@!/9L
*/ }1Mf0S
publicint getNum(){ \x4:i\Fx@
return num; D Vg$rm`
} ?Oy0p8
cCx{
")
/** ,-(D(J;}1
* if(num<1) num=1 7D 3-/_ v
*/ TOa6sB!H
publicvoid setNum(int num){ {=gJGP/}_
if(num < 1) ./'d^9{
num = 1; eMV8`&c'
this.num = num; "j8=%J{
} rHOhi|+
`e3$jy@
/** JwWxM3(%t
* 获得总页数 T9kc(i'
*/ 9CN'29c
publicint getPageNum(){ B#5[PX
return(count - 1) / num + 1; FK-q-PKO#.
} jpW_q+^?
cuy9QBB
:
/** V=1zk-XC
* 获得本页的开始编号,为 (p-1)*num+1 |:2B )X
*/ fWri7|"0h
publicint getStart(){ tgl 4pAc
return(p - 1) * num + 1; k w
} OkT@ _U
BE~-0g$W
/** _]D
6m2R
* @return Returns the results. !
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*/ D8Mq '$-
publicList<E> getResults(){ 5.yiNWh
return results; II~91IEk
} R@_3?Z!W=
sD{Wc%5
public void setResults(List<E> results){ kw2d<I$]
this.results = results; 1_c%p#?K
} GM)q\Hx{
5U]@
Y?
public String toString(){ 6zNWDUf
StringBuilder buff = new StringBuilder U:c0s
Pq(LW(
(); cyabqx
buff.append("{"); i`vy<Dvpz
buff.append("count:").append(count); utC^wA5U~
buff.append(",p:").append(p); 7&%#bMnw
buff.append(",nump:").append(num); f:~$x
buff.append(",results:").append }?+tX <j
\M0's&