Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &!ED# gs
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 3pvYi<<D'
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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 :6XguU
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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 6gXIt9B.h$
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。 <lUOJV{&\
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分页支持类: K&*iw`
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java代码: [+;qWfs B
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package com.javaeye.common.util; X*i/A<Y`=
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import java.util.List; O7%2v@j|8
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publicclass PaginationSupport { rah,dVE]
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publicfinalstaticint PAGESIZE = 30; + :V rip
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privateint pageSize = PAGESIZE; OA[&Za#w
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privateList items; F*M|<E=
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privateint totalCount; L'lF/qe^
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privateint[] indexes = newint[0]; (:5G#?6,
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privateint startIndex = 0; n-$VUo
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public PaginationSupport(List items, int EFAGP${F
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totalCount){ h{k_6ym
setPageSize(PAGESIZE); h4/X
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setTotalCount(totalCount); d6`OXTD
setItems(items); 3\AM=`
setStartIndex(0); .e@>
} 9Y/L?km_(
b;#\~(a
public PaginationSupport(List items, int ZPHXzi3j
btH _HE
totalCount, int startIndex){ 5o#Yt
setPageSize(PAGESIZE); FW8-'~
setTotalCount(totalCount); rz%<AF Z
setItems(items); 1G;8MPU
setStartIndex(startIndex); JWROYED
} nBN&.+3t
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public PaginationSupport(List items, int Gih[i\%Q
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totalCount, int pageSize, int startIndex){ SHD^}?-|
setPageSize(pageSize); . w H*sb
setTotalCount(totalCount); Y#FO5O%W
setItems(items); +E/y ~s
setStartIndex(startIndex); Q6IQV0{p
} ,LZX@'5
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publicList getItems(){ ;Wc4qJ.@
return items; (vc|7DX M
} iEIg:
?7[alV ~
publicvoid setItems(List items){ '9s5OTkN ;
this.items = items; w5KPB5/zu
} 1f#mHt:(
k6"KB
publicint getPageSize(){ WZZ4]cC
return pageSize; wvMW|
} cu&,J#r%
zP!J/}z
publicvoid setPageSize(int pageSize){ >O7~h[FN
this.pageSize = pageSize; p@YB?#Im
} Zj*\"Ol
PWB(5 f?
publicint getTotalCount(){ 7\XE,;4>
return totalCount; 9b;A1gu
} QvLZg
Sm-wH^~KA
publicvoid setTotalCount(int totalCount){ FJNF%a)x2I
if(totalCount > 0){ ?":'O#E
this.totalCount = totalCount; >u0w.3r#
int count = totalCount / j>Ag\@2ME
la
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pageSize; %UZVb V
if(totalCount % pageSize > 0) ^j )BKD-
count++; K93p"nHN
indexes = newint[count]; ]"~51HQZ
for(int i = 0; i < count; i++){ X"q!Y#)
indexes = pageSize * k~3.MU
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i; Q;u SWt<{
} U__(;
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}else{ ZJ,cQ+fn
this.totalCount = 0; Thr*^0$C
} 7@}$|u:JUF
} ;AJTytE>%
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publicint[] getIndexes(){
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return indexes; RthT\%R
} awewYf$li
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publicvoid setIndexes(int[] indexes){ AVw%w&|%
this.indexes = indexes; 17.x0gW,
} zsXoBD\h
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publicint getStartIndex(){ m-/j1GZ*
return startIndex; qTQ!jN
} "xRBE\B
os lJC$cy'
publicvoid setStartIndex(int startIndex){ <?Wti_ /M
if(totalCount <= 0) q2rUbU_A(
this.startIndex = 0; x]|+\1
elseif(startIndex >= totalCount) m~hoE8C$
this.startIndex = indexes s;flzp8
8>WVodv
[indexes.length - 1]; V DS23Bo
elseif(startIndex < 0) )yK[ Zb[
this.startIndex = 0; HO)/dZNU
else{ p&-'|'![l
this.startIndex = indexes 'R<&d}@P*#
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[startIndex / pageSize];
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} 5kNzv~4B,;
} SLfFqc+n0
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publicint getNextIndex(){ X|D!VX>#!
int nextIndex = getStartIndex() + l`-bFmpA
u{N,Ib
8
pageSize; ;6ecrQMw&
if(nextIndex >= totalCount) mo{MR:>)
return getStartIndex(); ._9
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else `(6r3f~XJ
return nextIndex; G rmzkNlN
} kql0J|P?
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publicint getPreviousIndex(){ E m
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int previousIndex = getStartIndex() - bI)u/
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pageSize; c#IYFTz
if(previousIndex < 0) ph>7?3;t
return0; Cxod[$8
else 9+s.w25R
return previousIndex; ml|W~-6l
} >odbOi+X
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} obrl#(\P
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抽象业务类 r0d35
java代码: m'\ 2:mDu0
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/** ?{w3|Ef&
* Created on 2005-7-12 h_1T,f(
*/
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package com.javaeye.common.business; uXDq~`S
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import java.io.Serializable; g.c8FP+
import java.util.List; KDl_?9E5
Hn>B!Bm*
import org.hibernate.Criteria; I1oje0$
import org.hibernate.HibernateException; rqPFU6
import org.hibernate.Session; 7QKr_
import org.hibernate.criterion.DetachedCriteria; K{b(J
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import org.hibernate.criterion.Projections; &[NG]V!Oc
import G7--v,R1x
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org.springframework.orm.hibernate3.HibernateCallback; *_E|@y
import cLPkK3O\=
pj4!:{.;
org.springframework.orm.hibernate3.support.HibernateDaoS \Y6WSj?E
9% l%
upport; Yt|6
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import com.javaeye.common.util.PaginationSupport; 6 3`{.yZ*z
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public abstract class AbstractManager extends &B!
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HibernateDaoSupport { ~%?`P/.o
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privateboolean cacheQueries = false; |-V&O=!^+
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privateString queryCacheRegion; O+}qQNe<
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publicvoid setCacheQueries(boolean Mu'8;9_6
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cacheQueries){ ;nC.fBu
this.cacheQueries = cacheQueries; ?4H i-
} it] E-^2>
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publicvoid setQueryCacheRegion(String |FD }e)
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queryCacheRegion){ A,r*%&4~
this.queryCacheRegion = vad12WrG<
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queryCacheRegion; pv^O"Bs
} hx/N1x
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publicvoid save(finalObject entity){ Dfq(Iv
getHibernateTemplate().save(entity); ;<G=M2
} G8Nt
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publicvoid persist(finalObject entity){ gX0R)spg
getHibernateTemplate().save(entity); r$]HIvJD
} dnV[ P
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publicvoid update(finalObject entity){ )M__
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getHibernateTemplate().update(entity); \:'%9 x
} dCj,b$
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publicvoid delete(finalObject entity){ ~z" =G5|
getHibernateTemplate().delete(entity); @6l%,N<fou
} JK.ZdY%
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publicObject load(finalClass entity, ^bEc6`eE
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finalSerializable id){ ;FZ@:%qDm
return getHibernateTemplate().load Sm~l:v0%
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(entity, id); H\XP\4#u
} XJLQ{
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publicObject get(finalClass entity, [oF|s-"9!
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finalSerializable id){ L#vI=GpL,r
return getHibernateTemplate().get &ZL3{M
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(entity, id); 5uxBK"q
} SPp#f~%m
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publicList findAll(finalClass entity){ u]vQ>Uu
return getHibernateTemplate().find("from 765p/**
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" + entity.getName()); 1KjU ]
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} )T k1 QHU
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publicList findByNamedQuery(finalString 97ql5
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namedQuery){ F'hHK.tT
return getHibernateTemplate 8T(e.I
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().findByNamedQuery(namedQuery); z)HD`Ho
} h,Q3oy\s1
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publicList findByNamedQuery(finalString query, ?s:d[To6
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finalObject parameter){ V*W;OiE_3
return getHibernateTemplate 3> Y6)
H@ t'~ZO
().findByNamedQuery(query, parameter); o1<_fI
} }N*_KzPIa
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publicList findByNamedQuery(finalString query, ~i `>adJ:
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finalObject[] parameters){ rL}YLR
return getHibernateTemplate 92^w8Z.
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().findByNamedQuery(query, parameters); Y +Fljr*
} ;pnD0bH
ij?
publicList find(finalString query){ IEU^#=n
return getHibernateTemplate().find C:Hoq(
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(query); qG<$Ajiin
} {l |E:>Q2
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publicList find(finalString query, finalObject %Q.&ZhB
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parameter){ 4fe7U=# ;Y
return getHibernateTemplate().find Fy.\7CL>
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(query, parameter); yrR1[aT
} HeG)/W?r
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public PaginationSupport findPageByCriteria IKi5 v~bE
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(final DetachedCriteria detachedCriteria){ 8cA~R-
return findPageByCriteria X=>=5'
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); &B|D;|7H
} zD<or&6
)HvnoUO0
public PaginationSupport findPageByCriteria d'Zqaaf k%
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(final DetachedCriteria detachedCriteria, finalint ,u/aT5\_
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startIndex){ 9ksE>[7
return findPageByCriteria ]niJGt
yR4|S2D3xn
(detachedCriteria, PaginationSupport.PAGESIZE, u?+Kkkk
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startIndex); ^.>jGI%rB
} (7 r<''
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public PaginationSupport findPageByCriteria IV)<5'v
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?k
(final DetachedCriteria detachedCriteria, finalint "U\4:k`:
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pageSize, kS!viJwtT
finalint startIndex){ LA`*_|}qcR
return(PaginationSupport) ak;*W
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getHibernateTemplate().execute(new HibernateCallback(){ 0$-xw
publicObject doInHibernate HvVts\f
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(Session session)throws HibernateException { Lliqj1&
Criteria criteria = N"3b{Qio
$ >EYhLBa
detachedCriteria.getExecutableCriteria(session); MX@_=Sp-
int totalCount = 3}/&w\$
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((Integer) criteria.setProjection(Projections.rowCount 2/0v B>
n-%s8aaVf
()).uniqueResult()).intValue(); ~}+Hgi
criteria.setProjection o0pII )v
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(null); ;
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List items = 3:C oZ
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criteria.setFirstResult(startIndex).setMaxResults d.P\fPSD
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(pageSize).list(); zA1lca0HK
PaginationSupport ps = -*XCxU'
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new PaginationSupport(items, totalCount, pageSize, ;dzL}@we
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startIndex); }|XtypbL
return ps; Q^#;WASi
} B|&"#Q
}, true); EcCFbqS4W
} IqD_GL)Ms
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public List findAllByCriteria(final `3hSLR
@0SC"CqM
DetachedCriteria detachedCriteria){ v_nj$1dY6
return(List) getHibernateTemplate V7Mh-]
R>(@ZM&
().execute(new HibernateCallback(){ 1Y]TA3:
publicObject doInHibernate /=gOa\k|p
2^l[(N
(Session session)throws HibernateException { =hMY2D
Criteria criteria = R<=zCE `:
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detachedCriteria.getExecutableCriteria(session); ivW(*c
return criteria.list(); tz&y*e&
} {1b Zg
}, true); d{E}6)1=
} x*Y@Q?`>5W
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public int getCountByCriteria(final U~ck!\0&T
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DetachedCriteria detachedCriteria){ b%S62(qP
Integer count = (Integer) q2et|QCru
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getHibernateTemplate().execute(new HibernateCallback(){ zBe8,, e
publicObject doInHibernate `IY/9'vT
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(Session session)throws HibernateException { KFFSv{m[
Criteria criteria = ?IGVErnJJC
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detachedCriteria.getExecutableCriteria(session);
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return cJL'$`gWf
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L
criteria.setProjection(Projections.rowCount ?A )hN8
&[;HYgp
()).uniqueResult(); 6A=8+R'`F
} [/BE8]M~
}, true); Y>&Ew*Y
return count.intValue(); Z" uY}P3
}
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} _X'"w|0
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用户在web层构造查询条件detachedCriteria,和可选的 dH^ <t,v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ~fo6*g:f1
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PaginationSupport的实例ps。 xu'yVt9RC
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ps.getItems()得到已分页好的结果集 //4Xq8y
ps.getIndexes()得到分页索引的数组 bpxeznz
ps.getTotalCount()得到总结果数 H
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ps.getStartIndex()当前分页索引 `Ps:d^8*P
ps.getNextIndex()下一页索引 m,t|IgDh
ps.getPreviousIndex()上一页索引 gL3"Gg3
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 yOwA8^q
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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 %bdjBa}
"1-}A(X
一下代码重构了。 _IdRF5<4
HWVtop/
我把原本我的做法也提供出来供大家讨论吧: >N.]|\V
-@Uqz781
首先,为了实现分页查询,我封装了一个Page类: q/4 [3h
java代码: E~a3r]V/
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51QRM32Y
/*Created on 2005-4-14*/ A|@_}h"WG
package org.flyware.util.page; d` [HT``
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/** V3ndV-uQE
* @author Joa RTFZPq84
* V14B[|YM<
*/ .YZgOJi
publicclass Page { rgOfNVyJG<
STJJU]H
/** imply if the page has previous page */ 5j-]EJb
privateboolean hasPrePage; f u9Cx
T =2=k&|
/** imply if the page has next page */ 2 6>ZW4Z
privateboolean hasNextPage; U.@*`Fg
''kS*3
/** the number of every page */ =Z+nX0qF
privateint everyPage; 7YAIA%8
y7|P-3[ 4w
/** the total page number */ 0{j&6I2
privateint totalPage; "t0kAG
k}#;Uy=5
/** the number of current page */ ts8+V<g
privateint currentPage; "jaJr5Wv=y
mB\C?=_
/** the begin index of the records by the current 2"-S<zM
~%2pp~1K
query */ sIv)'
privateint beginIndex; `~W-Xx
g38&P3/
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/** The default constructor */ E[^ {w
public Page(){ M1%Dg'}G
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} J=dJsk
/QEiMrz@6
/** construct the page by everyPage 1*
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* @param everyPage :F?x)"WoQ+
* */
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public Page(int everyPage){ 2z@\R@F
this.everyPage = everyPage; aceZ3U>W
} C8L'si
+L=*:e\j
/** The whole constructor */ y8\S}E0
public Page(boolean hasPrePage, boolean hasNextPage, @EoZI~
)aX2jSp
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int everyPage, int totalPage, $ F S_E
int currentPage, int beginIndex){ )=DGdIEt
this.hasPrePage = hasPrePage; Z,X'-7YkU
this.hasNextPage = hasNextPage; -`Y:~q1
this.everyPage = everyPage; \-*eL;qP
this.totalPage = totalPage; wI5Yn
h
this.currentPage = currentPage; YQ0)5 }
this.beginIndex = beginIndex; |~
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} "p3_y`h6+
9TAj) {U%'
/** SI6B#u-i
* @return [>|FB '
* Returns the beginIndex. >\!4Mk8
*/ Bu]t*$
publicint getBeginIndex(){ LA[g(i 7
return beginIndex; jp+_@S>
} Pe2w sR"_U
:ZDMNhUl
&
/** ph2$oO
6,
* @param beginIndex Oi} T2I
* The beginIndex to set. &Sp -w?kM
*/ HBB{m
publicvoid setBeginIndex(int beginIndex){ DSxUdEK6
this.beginIndex = beginIndex; .6~`Ubr}E
} **>/}.%?K
/xJqJ_70X
/** LZ~"VV^
* @return $M:3 XAN
* Returns the currentPage. Em7 WDu0
*/ J# kl
7
publicint getCurrentPage(){ vJ`.iRU|
return currentPage; ; <Km3
} {5|("0[F
|([R'Orm
/** /1`cRyS
* @param currentPage }!TL2er_
* The currentPage to set. Bg8#qv
*/ z5]bia,
publicvoid setCurrentPage(int currentPage){ *{o UWt
this.currentPage = currentPage; ,pBh`av
} T$=4O9G
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/** pA4*bO+
* @return ]h9!ei
[
* Returns the everyPage. QjPj[c
*/ $t-n'Qh^2
publicint getEveryPage(){ jtm?z c
return everyPage; ^S#t|rN
} G9g6.8*&
},[;O^Do^{
/** Pj?Dmk~
* @param everyPage
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* The everyPage to set. gf)t)- E
*/ j6ut}Uq
publicvoid setEveryPage(int everyPage){ ,DnYtIERo
this.everyPage = everyPage; mceG!@t
} 1t9 .fEmT
l|V;Ys5f
/** 4l8BQz}sb
* @return ;PyZ?Z;
* Returns the hasNextPage. >\A8#@1
*/ k#:2'!7G
publicboolean getHasNextPage(){ (5$ZvXx?}
return hasNextPage; AD('=g J
} VzlDHpG
K^t?gt@k}
/** r gcWRt
* @param hasNextPage <f~Fl^^8
* The hasNextPage to set. Bf4%G,o5
*/ a1N!mQ^
publicvoid setHasNextPage(boolean hasNextPage){ Wd(86idnc
this.hasNextPage = hasNextPage; `3q;~ 9
} DW(~Qdk
0F;,O3Q
/** 1f(DU4h
* @return k6\^p;!Y
* Returns the hasPrePage. C+NF9N
*/ {w^uWR4f
publicboolean getHasPrePage(){ jQj,q{eA
return hasPrePage; ;2giZ\
} f*xpE`&
<JI&
{1
/** 1MA@JA:T
* @param hasPrePage 34|a:5c
* The hasPrePage to set. AN9[G
*/ 5c-N0@\
publicvoid setHasPrePage(boolean hasPrePage){ (S^ck%]]a!
this.hasPrePage = hasPrePage; EqM;LgE=
} #<CIFVH
BC\S/5~k
/** bZipm(e
* @return Returns the totalPage. ")lw9t`
* HT`1E0G8)
*/ }{],GHCjQ
publicint getTotalPage(){ G\iyJSj[P
return totalPage; G{
mC7@
} v
vE\
`3iQZui
/** 1x >iz
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* @param totalPage KhM.Tc
* The totalPage to set. :]eb<J
*/ QYThW7S
publicvoid setTotalPage(int totalPage){ ~S(^T9R
this.totalPage = totalPage; mgkyC5)d
} pvXcLR)L+3
6/mF2&&g
} rj H`
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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 @Z\~
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个PageUtil,负责对Page对象进行构造: xX@FWAj
java代码: N?23 m`3
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/*Created on 2005-4-14*/ t%+$"nP
package org.flyware.util.page; G?V"SU.
QD<eQsvV
import org.apache.commons.logging.Log; jQtSwVDr
import org.apache.commons.logging.LogFactory; :%tuNJjj
V_a)jJ
/** OV5e#AOy)
* @author Joa ESDB[
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* T{S4|G1R6
*/ QB 77:E
publicclass PageUtil { t =dO
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privatestaticfinal Log logger = LogFactory.getLog 4#Eul
Jyu`-=It
(PageUtil.class); mtw9AoO
J_ V,XO
/** zLek&s&-
* Use the origin page to create a new page FDLd&4Ex
* @param page V-vlTgemwc
* @param totalRecords <TjBd1
* @return zk>h u<_
*/ |< N frz
publicstatic Page createPage(Page page, int NfF~dK|
_bI+QC#
totalRecords){ S;}qLjT
return createPage(page.getEveryPage(), If.n(t[M9
|%ZpatZA5
page.getCurrentPage(), totalRecords); fS./y=j(X
} 6GKT yN
J E)J<9gf
/** u7muaSy
* the basic page utils not including exception `-D$Fsl
VG#Q;Xd}
handler V.,bwPb{9
* @param everyPage K+mU_+KRp
* @param currentPage R`Qpd3
* @param totalRecords sx-F8:Qa
* @return page c)3O/`
*/ P^(.tr3t
publicstatic Page createPage(int everyPage, int &|=?acv
4 =Fg!Eu<
currentPage, int totalRecords){ H7jTQW0rp5
everyPage = getEveryPage(everyPage); cV]y=q6
currentPage = getCurrentPage(currentPage); ; J2-rh
int beginIndex = getBeginIndex(everyPage, lO&cCV;
BE%Z\E[[m
currentPage); '49L(>.
int totalPage = getTotalPage(everyPage, /c^e&D
T~:_}J
totalRecords); GYqJ!,
boolean hasNextPage = hasNextPage(currentPage, cQ,9Rnfl,
;o >WXw
totalPage); @ta?&Qf)
boolean hasPrePage = hasPrePage(currentPage); 6z]`7`G
%O /d4
returnnew Page(hasPrePage, hasNextPage, s]bPV,"p
everyPage, totalPage, AP
;*iyQ[
currentPage, ~R{8.!: >
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beginIndex); LR\zy8y]
} :A*0 ]X;
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privatestaticint getEveryPage(int everyPage){ +:y&{K
return everyPage == 0 ? 10 : everyPage; lA4hm4"i(,
} &(0N.=R
L?.7\a@
privatestaticint getCurrentPage(int currentPage){ _3U|2(E
return currentPage == 0 ? 1 : currentPage; acP
;(t
} DvJB59:_}
eE,;K1
privatestaticint getBeginIndex(int everyPage, int J=P;W2L
pe#*I/)b
currentPage){ Yhk6Uog{4
return(currentPage - 1) * everyPage; 2+&R"#I
} r./z,4A`
#4q1{)=
privatestaticint getTotalPage(int everyPage, int ^yD"d =z
N&N 82OG
totalRecords){ lrn+d$!@
int totalPage = 0; %/md"S
kdd7Xbw-
if(totalRecords % everyPage == 0) kDg{>mf
totalPage = totalRecords / everyPage; wXcMt>3
else :o<N!*pT
totalPage = totalRecords / everyPage + 1 ; H8<m9zDvl
L"9 Gc
return totalPage; 7 BK46x
} 776 nWw)
!*8#jy
privatestaticboolean hasPrePage(int currentPage){ H-m`Dh5{
return currentPage == 1 ? false : true; &]*|6cR$E
} aa!a&L|!
}JH`'&3
privatestaticboolean hasNextPage(int currentPage, *XOS. $zGz
B%y! aQep
int totalPage){ i&1U4q
return currentPage == totalPage || totalPage == _&K\D
p&@
gTuX *7w
0 ? false : true; XX:q|?6_ 4
} V-:`+&S{^
9kUV1?
Gzj3Ka
} 9g4QVo|
jvWI_Fto
7Qt2gf
/Q]:Uf.J
Ef-a4Pi
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 BQuRHi IV
f{f_g8f[
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 !HvGlj@(|
=s6E/K
做法如下: fls#LcI9>6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~X[S<Gi#
jJ*=Ghu-
的信息,和一个结果集List: B0S8vU
java代码: N]V/83_
>|5XaaDa
xdCs5ko
/*Created on 2005-6-13*/ v<%]XHN
package com.adt.bo; XEa~)i{O
X+d&OcO=q
import java.util.List; `|uoqKv
~DK F%}E
import org.flyware.util.page.Page; }]tFz}E\
I>d I[U
/** Wf_CR(
* @author Joa 4@ =
aa
*/ 4VC/-.At
publicclass Result { 9armirfV'P
;Sy/N||
private Page page; z( *]'Y
l#p}{
private List content; KQ- ,W8Q5
a (P^e)<
/** P_v0))n{
* The default constructor }FHw"
{my
*/ F
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public Result(){ l&vm[3
super(); aX:#'eDB
} 5DmCxg
#"|"cYi,
/** iJEB?y
* The constructor using fields N\c&PS
* 9/FG,9
* @param page keq r%:E8
* @param content :EYu 4Y
*/ 56"#Syj
public Result(Page page, List content){ / *AJ+K._
this.page = page; -*rHB&e
this.content = content; &zO3qt6
} +SO2M|ru&
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/** kboizJp
* @return Returns the content. <>SR 4
*/ Zlr{L]c
publicList getContent(){ Sb'N];
return content; U LV)0SB
} G`9cd\^
\I'f3
/** +SAk:3.#CV
* @return Returns the page. ~*jsB=XM/
*/ 83\o(
public Page getPage(){ @X3 gBGY)
return page; FLVbkW-G.
} PbbXi
|= tJ|
/** GU:r vS!
* @param content X\o/i\ C}
* The content to set. -J-3_9I
*/ }DJ|9D^yf
public void setContent(List content){ 0m]~J_
this.content = content; /#:Rd^
} R.91v4J
Y')O>C0~
/** fui4@
* @param page W`w5jk'0^=
* The page to set. A4~D#V
*/ _!CK
publicvoid setPage(Page page){ |De!ti
this.page = page; }pbBo2
} - 3C* P
} muL>g_H
LvSP #$f
b`(yu.{Jn
9`)w@-~~
3'?h;`v\Lo
2. 编写业务逻辑接口,并实现它(UserManager, gJ<@;O8zu0
"Czz,;0
UserManagerImpl) )?!vJb"
java代码: X{5v?4wI
~AEqfIx*^&
[
c ~LY4:
/*Created on 2005-7-15*/ h5LJijJ
package com.adt.service; Bpk@ {E9
7$g*N6)Q
import net.sf.hibernate.HibernateException; ^Nd|+}
1<XiD3H;
import org.flyware.util.page.Page; =fKhXd
)ZS:gD
import com.adt.bo.Result; <Cf7E
;J,,f1Vw
/** Y|hzF:ll
* @author Joa 1TK #eU
*/ I><99cwFI
publicinterface UserManager { }V1DyLg:
4@/ q_*3o
public Result listUser(Page page)throws 0C7thl{Dms
1Qp1Es<)
HibernateException; o1fyNzq<
q#mFN/.(+
} :0J-ek.;
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A]m~=3
b9W<1eqF
syWv'Y[k?
;a!h.8UJPI
java代码: jyY ^iQ.2
cc2d/<:
?`vM#)
/*Created on 2005-7-15*/ *@-q@5r}!
package com.adt.service.impl; 9J-!o]f .b
NDs]}5#
import java.util.List; 9 NGeh*`
Z4wrXss~
import net.sf.hibernate.HibernateException; p%1xj2 ?nN
SXHru Z
import org.flyware.util.page.Page; ~>Hnf_pZO
import org.flyware.util.page.PageUtil; C }h<ldlY
#`N6<nb
import com.adt.bo.Result; q5?rp|7D
import com.adt.dao.UserDAO; bWX[<rh'
import com.adt.exception.ObjectNotFoundException; k$UzBxR
import com.adt.service.UserManager; Mm>zpB`qP
3/A[LL|
/** 6k@% +<1
* @author Joa T!=20 !I
*/ I:uQB!
publicclass UserManagerImpl implements UserManager { =0@d|LeZ
zJy 89ib'
private UserDAO userDAO; )|{1&F1
=u:6b} =
/** *6sJ*lh
* @param userDAO The userDAO to set. Qq;m"M /
*/ dCoi>PO
publicvoid setUserDAO(UserDAO userDAO){ )"pxry4v7J
this.userDAO = userDAO; 1,%#O;ya
} rHC+nou
QC\,
/* (non-Javadoc) W[1f]w3
* @see com.adt.service.UserManager#listUser Pt PGi^
Dj,+t+|
(org.flyware.util.page.Page) &G7)s%q
*/ w{:Oa7_A
public Result listUser(Page page)throws XoH[MJC
*Lb(urf
HibernateException, ObjectNotFoundException { 0?5%
int totalRecords = userDAO.getUserCount(); Fl#VKU3h
if(totalRecords == 0) :YRzI(4J
throw new ObjectNotFoundException U!;aM*67
"dLMBY~
("userNotExist"); lkSz7dr@
page = PageUtil.createPage(page, totalRecords); (8@hF#N1
List users = userDAO.getUserByPage(page); :ET3&J
L
returnnew Result(page, users); MoKXl?B<
} #v~S",*.f
R>e3@DQ~
} .Kh(F6
s
oQ-|\?{;A
>jrz;r
Vhbj.eX.)
x^='pEt{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 [:R P9r}
q~g&hR}K
询,接下来编写UserDAO的代码: [!dnm1
3. UserDAO 和 UserDAOImpl: +SuUI-.
java代码: ku[=QsMv
X>@.-{6T
iu6WGmR
/*Created on 2005-7-15*/ Z@.ol Y
package com.adt.dao; }ygbgyLa
TgQ|T57
import java.util.List; ,#
jOf{L*
N?mY|x\}wK
import org.flyware.util.page.Page; pRxlvVt
Q,,fDBN
import net.sf.hibernate.HibernateException; Nz>E#.++
iM\ZJ6
/** Y9H *S*n
* @author Joa ev;5?9\E
*/ "- j@GCme
publicinterface UserDAO extends BaseDAO { I3zitI;
,QHx*~9
publicList getUserByName(String name)throws M#lVPXS
5rHnU<H@y
HibernateException; &J&w4"0N'
'/yx_RK2?
publicint getUserCount()throws HibernateException; $Op/5j
{^$"/hj
publicList getUserByPage(Page page)throws V Q,\O
WEV{C(u<k!
HibernateException; K}5$;W#
vu.S>2Wv
} s!o<Pd yJK
X $9D0;L
RSWB!-
48&KdbGX
fssL'DD
java代码: 4KSP81}/\
I|3v&E1
T\e)Czz2-
/*Created on 2005-7-15*/ WfjUJw5x"s
package com.adt.dao.impl; o%~K4 M".
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import java.util.List; ^%*{:0'
73sAZa|
import org.flyware.util.page.Page; @qhg[= @
y1"^S
import net.sf.hibernate.HibernateException; 0&rH 9
import net.sf.hibernate.Query; VGDEP!)-8
RoM*Qjw
import com.adt.dao.UserDAO; wmcp`8w.
rW%'M#!
=
/** ~tj7zI6
* @author Joa P2:Q+j:PX
*/ X"khuyT_
public class UserDAOImpl extends BaseDAOHibernateImpl 1d@^,7MF-
J>|:T
implements UserDAO { f?<M3P
$E~Lu$|
/* (non-Javadoc) CL}I:/zRB
* @see com.adt.dao.UserDAO#getUserByName n$![b_)*
DwrCysIK
(java.lang.String) 'm!11Phe
*/ x]J-q5
publicList getUserByName(String name)throws &\]f!'jV
C^42=?
HibernateException { /h.3<HI."*
String querySentence = "FROM user in class VX>t!JP p
Z%n.:I<%ZV
com.adt.po.User WHERE user.name=:name"; D>x'3WYR
Query query = getSession().createQuery JK8@J9(#
?>\]%$5o
(querySentence); $Q$d\Yvi
query.setParameter("name", name); vLT12v:)`
return query.list(); fm:{&(
} zUgkY`]:BJ
G-i_s6Wu
/* (non-Javadoc) a5~C:EU0
* @see com.adt.dao.UserDAO#getUserCount() .idl@%
*/ -I-&<+7v
publicint getUserCount()throws HibernateException { .W+4sax:
int count = 0; i K[8At"Xo
String querySentence = "SELECT count(*) FROM Umwg
iw
; o@`l$O
user in class com.adt.po.User"; H=BR
-
Query query = getSession().createQuery j83Y'VJJC
=$zr
t
(querySentence); A`/7>'k/q[
count = ((Integer)query.iterate().next BMj&*p8R
]<_!@J6k
()).intValue(); BHE =Zo
return count; np>!lF:
} KeOBbe
K$v Rk5U
/* (non-Javadoc) +bd{W]={
* @see com.adt.dao.UserDAO#getUserByPage ~u`! Gi
EkAqFcKLq
(org.flyware.util.page.Page) yrYaKh
*/ ,v5>sL
publicList getUserByPage(Page page)throws &+{xR79+&
0|Ft0y`+
HibernateException { ?&nz
String querySentence = "FROM user in class L#@$Mtc
w>UV\`x
com.adt.po.User"; )ZU#19vr7
Query query = getSession().createQuery lz0]p
KIY_EE$?
(querySentence);
8=Y|B5
query.setFirstResult(page.getBeginIndex()) qq%_ksQ
.setMaxResults(page.getEveryPage()); ^[z\KmUqt
return query.list(); k+G4<qw
} vlyNQ7"%
CKt~#$ I%
} h?tV>x/Fu
{Om3fSk:
vgZPDf|
ghQsS|)p.
M 6Z`Pwv];
至此,一个完整的分页程序完成。前台的只需要调用 acZ|H
J;Xz'0
userManager.listUser(page)即可得到一个Page对象和结果集对象 :*%\i' $!/
e/D\7Pf
的综合体,而传入的参数page对象则可以由前台传入,如果用 ,ZW.P`
L`@&0Zk
webwork,甚至可以直接在配置文件中指定。 ?gP/XjToMg
|-Klh
下面给出一个webwork调用示例: l>P~M50D?{
java代码: =|zLr"
o@~gg*
/38Pp%
/*Created on 2005-6-17*/ UiN ^x
package com.adt.action.user; by ee-BU
'N/%SRk
import java.util.List; JkEQ@x
-;.fU44O[#
import org.apache.commons.logging.Log; }(O
kl1
import org.apache.commons.logging.LogFactory; 1L9
<1
import org.flyware.util.page.Page; EHJc*WFPU-
|8+rUFkU8
import com.adt.bo.Result; L| qY
import com.adt.service.UserService; ArKrsI#H-
import com.opensymphony.xwork.Action; ,\RC gc
S%|'
/cFo
/** sW`iXsbWM>
* @author Joa k)_#u;qmG
*/ LYKm2C*d
publicclass ListUser implementsAction{ 5S?Xl|8E
Ek\Zi#f<
privatestaticfinal Log logger = LogFactory.getLog w5R9\<3L
YWd(xm"4
(ListUser.class); kQcQi}e
|EU08b]P29
private UserService userService; wC@U/?
aa3YtNpP
private Page page; F&Z>B};
N.J:Qn`(
privateList users; #f@53Pxb
9Ky,oB
/* $>`8'I
* (non-Javadoc) XwGJ 8&N
*
t/c^hTT
* @see com.opensymphony.xwork.Action#execute() #Z5~a9rO
*/ "lMWSCas
publicString execute()throwsException{ #jR?C9&!(
Result result = userService.listUser(page); 9$t@Gmn
page = result.getPage(); wIPDeC4
users = result.getContent(); VJPP HJ[-
return SUCCESS; r8E!-r}rno
} LDNUywj@w
&$
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/** n6dg
* @return Returns the page. \Bf{/r5x
*/ ON^u|*kO
public Page getPage(){ g:V6B/M&
return page; ;0WlvKF
} P|4a}SWU
3*L,48wX
/** iE{ SqX
* @return Returns the users. <]J5AdJ
*/ Xp@OIn
publicList getUsers(){ .-
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return users; p_5+L@%Gb
} ={d\zjI$
.4-S|]/d,
/** 4cL=f
* @param page JaTW/~ TU
* The page to set. S|i
//I%_
*/ JD.z}2+
publicvoid setPage(Page page){ kSrzIq<xre
this.page = page; @:8|tJu8b
} ^B>6!
L.(k8eX
/** Z$gY}Bz
* @param users P#]jPW
* The users to set. 8;@eY`0(
*/ 4+Kc
publicvoid setUsers(List users){ ul1Vsj
this.users = users; +z_0 ?x
} gqamGLK
:\XD.n-n
/** 6y5~Kh6
* @param userService UJ+JVj
* The userService to set. p<NgT1"{
*/ q9>w3
<
publicvoid setUserService(UserService userService){ {w(N9Va,(
this.userService = userService; ^|2qD:
;
} W*#/@/5
} jLU)S)
SX.v5plhc
XPSWAp)
G%{jU'2
fzcT(y
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, Xb {y*',
2oRmro
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 T/nRc_I+^B
6{ Eh={:b
么只需要: 1U!CD-%(
java代码: 5,3h'\ "!
h&P[9:LH
N~_gT
Jr~P
<?xml version="1.0"?> :8FH{sqR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork z%z$'m
+xa2e?A%L
1.0//EN" "http://www.opensymphony.com/xwork/xwork- YrX{,YtiX
G5Nub9_*X
1.0.dtd"> y+_U6rv[
?UzHQr
<xwork> 5Dd;?T>
Z(cgI5Pu
<package name="user" extends="webwork- G}x^PJJt
7Udr~0_)
interceptors"> g|Cnj
">7 bnOJ
<!-- The default interceptor stack name A.Njn(z?Lz
c
s>W6
--> nN:i{t4f
<default-interceptor-ref GbhaibkO
^[6AOz+L
name="myDefaultWebStack"/> )Lq FZ~B
yWy9IWI["
<action name="listUser" c|XnPqo;f
E6uIp^E
class="com.adt.action.user.ListUser"> .#SWfAb2h
<param +|N"i~f>j
rx<fjA%
name="page.everyPage">10</param> ftbu:RtK^^
<result +Aq}BjD#
te_D
,
name="success">/user/user_list.jsp</result> .$rcTZ
</action> B7
T+a
W# $rC<Jh]
</package> asb")NfIm
R[6&{&E:
</xwork> !Wk "a7
ay2.CBF
pAYuOk9n
{chl+au*l
g~]FI
(,k=mF
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 ?V+=uTCq
UaB!,vs3st
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。 >A6lX)
tO# y4<
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 #Uo
9BM
<