Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .&x?`pER
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 %H}Y]D~R
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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 !$xEX,vj|W
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 KHus/ M&0
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分页支持类: fd"~[z [
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java代码: 4`-?r%$,:
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package com.javaeye.common.util; Vc52s+7=8
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import java.util.List; WUWb5xA
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publicclass PaginationSupport { @
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publicfinalstaticint PAGESIZE = 30; qv*uM0G6i
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privateint pageSize = PAGESIZE; ~sHZh
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privateList items; Y5i`pY/}#?
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privateint totalCount; D@(M+u9/%
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privateint[] indexes = newint[0]; ?J@?,rZQ^V
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privateint startIndex = 0;
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public PaginationSupport(List items, int aBVEk2 p
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totalCount){ tD~PvUJ
setPageSize(PAGESIZE); >_0 i=.\
setTotalCount(totalCount); Q"6hD?6.
setItems(items); e7bT%h9i
setStartIndex(0); &^3~=$
} ?`
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public PaginationSupport(List items, int ptWG@"j/b
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totalCount, int startIndex){ x:n9dm
setPageSize(PAGESIZE);
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setTotalCount(totalCount); 2.Eu+*UC
setItems(items); kJvy<(iG
setStartIndex(startIndex); ngkeJ)M0$
} '^F|k`$r
\;B$hT7z*
public PaginationSupport(List items, int Zn<(,e
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totalCount, int pageSize, int startIndex){ 4j@kMe;RjZ
setPageSize(pageSize); ySuLt@X
setTotalCount(totalCount); zA'gb'MmW
setItems(items); -0KbdHIKb'
setStartIndex(startIndex); [zh4W*K_cq
} "\zj][sL
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publicList getItems(){ csFJ5
return items; 1IF'>*
} C DnR
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publicvoid setItems(List items){ SZK)q
this.items = items; 4gv.E 0Fo
} ^iV`g?z
d#vSE.&
publicint getPageSize(){ 94h_t@Q/1
return pageSize; 0x]OF8=J
} ~D-JZx
RvPniT(<?
publicvoid setPageSize(int pageSize){ 0[2BY]`Z.
this.pageSize = pageSize; (ifqwl62
} FD
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publicint getTotalCount(){ qr'x0r|<>
return totalCount; \C+*loLs
} ~`~%(DA=
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publicvoid setTotalCount(int totalCount){ da9*9yN
if(totalCount > 0){ (pT(&/\8
this.totalCount = totalCount; co$Hi9JE
int count = totalCount / z|G|Y 22
}rKJeOo^x?
pageSize; ,#P,B;r~
if(totalCount % pageSize > 0) &Hlm{FHU
count++; 7z/(V\9B
indexes = newint[count]; +(=0CA0GE
for(int i = 0; i < count; i++){ Qc&-\kQ:$u
indexes = pageSize * SLQ\Y%F
SG
dfhno;
i; y~==waZw
} 2,8/Cb
}else{ *l> [`U+
this.totalCount = 0; ;T5,T
} 6Q.{llO
} wO2V%v^bp
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publicint[] getIndexes(){ RV0>-@/x
return indexes; z)58\rtz
} ,Lt~u_ lve
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publicvoid setIndexes(int[] indexes){ IdV,%d{
this.indexes = indexes;
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} .6O52E
H )BOSZD
publicint getStartIndex(){ ),nCq^Bp
return startIndex; iA55yT+
} $zk^yumdE
*Fa)\.XX
publicvoid setStartIndex(int startIndex){ )K>Eniou
if(totalCount <= 0) 05l0B5'p
this.startIndex = 0; c N02roQl
elseif(startIndex >= totalCount) ] ?DDCew
this.startIndex = indexes Q(~3pt
@9}),hl`
[indexes.length - 1]; zdxT35h
elseif(startIndex < 0) a,/M'^YyN
this.startIndex = 0; w?]ZU-
else{ e-[>( n/[
this.startIndex = indexes HG{&U:>)
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[startIndex / pageSize]; ]dPVtk
} 0t#NMW
} P &;y]
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publicint getNextIndex(){ y-w2O]
int nextIndex = getStartIndex() + Ujce |>Wn
L#
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pageSize; ,N;))3
if(nextIndex >= totalCount) 'i@,~[Z4
return getStartIndex(); zW*}`S"
else vKcl6bVT
return nextIndex; |A ;o0pL
} OOEV-=
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publicint getPreviousIndex(){ 89LpklD
int previousIndex = getStartIndex() - ]]el|
E
S#rs="
pageSize; u~$WH, P3
if(previousIndex < 0) pyUNRqp
return0; Jt##rVN
else L8K0^~Mk
return previousIndex; 4`'8fe/"
} [8,PO
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} 'M~BE\
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抽象业务类 Z} c'Bm(
java代码: _LJ5o_-N
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/** z7-`Y9Ypd
* Created on 2005-7-12 +O)]^"TG
*/ 3^!Hl8P7
package com.javaeye.common.business; Q Oz9\,C
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import java.io.Serializable; DZ^=*.
import java.util.List; X Y~;)<s_
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import org.hibernate.Criteria; "Kyifw?
import org.hibernate.HibernateException; /nc~T3j
import org.hibernate.Session; {*N^C@
import org.hibernate.criterion.DetachedCriteria; .4wTjbO6
import org.hibernate.criterion.Projections; fJX\'Rc\
import +IG1IF
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org.springframework.orm.hibernate3.HibernateCallback; }0$mn)*k
import vT?Q^PTO
;4!=DFbU
org.springframework.orm.hibernate3.support.HibernateDaoS
}c}
( 5
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upport;
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import com.javaeye.common.util.PaginationSupport;
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public abstract class AbstractManager extends U);OR
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HibernateDaoSupport { 1 ojhh7<
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privateboolean cacheQueries = false; L59bu/LfL
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privateString queryCacheRegion; XdcG0D^
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publicvoid setCacheQueries(boolean ]$3+[9x'
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cacheQueries){ CoJ55TAW
this.cacheQueries = cacheQueries; ^"1TPd|
} cFLd)mt/
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publicvoid setQueryCacheRegion(String T'8RkDI}-
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queryCacheRegion){ ]pWP?Ws
this.queryCacheRegion = &} ,*\Oj
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queryCacheRegion; !6Q`>s]
} \ EZ+#3u
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publicvoid save(finalObject entity){ ,*dzJT$k
getHibernateTemplate().save(entity); X:Q$gO?[4
} gA_krK,Z
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publicvoid persist(finalObject entity){ 7$
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getHibernateTemplate().save(entity); .!i0_Rv5x
} ;+
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publicvoid update(finalObject entity){ e&2wdH&
getHibernateTemplate().update(entity); J/t!-!
} }w@gj"\H
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publicvoid delete(finalObject entity){ @;m$ua*|:
getHibernateTemplate().delete(entity); Vu[:A
} X/Y#U\
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publicObject load(finalClass entity, 0qv$:w)g+v
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finalSerializable id){ /&h+t^l_Qj
return getHibernateTemplate().load "x&3Z@q7
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(entity, id); >Rt9xP
} g]|_
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publicObject get(finalClass entity, $M':&i5`,
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finalSerializable id){ v)):$s?WB
return getHibernateTemplate().get Wt J{
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(entity, id); w>qCg XU3
} (S oo<.9~
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publicList findAll(finalClass entity){ =Y9\DeIZ
return getHibernateTemplate().find("from pcH<gF(k
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" + entity.getName()); J{Tq%\a3
} ^Dr.DWi{$
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publicList findByNamedQuery(finalString cx^{/U?9}
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namedQuery){ BDe]18X
return getHibernateTemplate #dc1pfL!y{
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().findByNamedQuery(namedQuery); B,_`btJh
} ''S&e
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publicList findByNamedQuery(finalString query, .
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finalObject parameter){ g_w&"=.jBq
return getHibernateTemplate aI(>]sWJ
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().findByNamedQuery(query, parameter); 5j eO"jB
} ]` ]g@v
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publicList findByNamedQuery(finalString query, kq-6HDR
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finalObject[] parameters){ DA"}A`HfI
return getHibernateTemplate @T&t.|`
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().findByNamedQuery(query, parameters); =MLf[
} XoR>H4xh
+y&d;0!
publicList find(finalString query){ ?t rV72D
return getHibernateTemplate().find "&lN\&:
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(query); ~ y;y(4<
} jxw_*^w"
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publicList find(finalString query, finalObject <y)E>Fl
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parameter){ ip``v0Nf
return getHibernateTemplate().find Yv)aAWEa
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(query, parameter); Dag`>|my
} 6T+
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public PaginationSupport findPageByCriteria RY=1H
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(final DetachedCriteria detachedCriteria){ z^W$%G
return findPageByCriteria l#bAl/c`
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 6^#uLp>
} s_eOcm
/\=MBUN
public PaginationSupport findPageByCriteria |}[nH>
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(final DetachedCriteria detachedCriteria, finalint XM~~y~j
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startIndex){ pCU*@c!
return findPageByCriteria I^3:YVR&
nl1-kB)$e|
(detachedCriteria, PaginationSupport.PAGESIZE, 61_f3S(u
Vq ^]s$'
startIndex); !gP0ndRJ=
} Yck~xt&]
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public PaginationSupport findPageByCriteria cxP6-tV%
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(final DetachedCriteria detachedCriteria, finalint u&]vd /
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pageSize, >dQ K.CG
finalint startIndex){ 8`v$liH
return(PaginationSupport) |(% u}V?
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getHibernateTemplate().execute(new HibernateCallback(){ A6UO0lyu
publicObject doInHibernate mBk5+KyT
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(Session session)throws HibernateException { l@~LV}BI
Criteria criteria = \#dl6:"
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detachedCriteria.getExecutableCriteria(session); F#V q#|_)>
int totalCount = p-$Cs _{Z
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((Integer) criteria.setProjection(Projections.rowCount u oVNK
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()).uniqueResult()).intValue(); eN-au/kN
criteria.setProjection BC/_:n8O
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(null); tRfm+hqRZ
List items = .FP$ IWt/1
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criteria.setFirstResult(startIndex).setMaxResults WDx
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?Zcj}e.r
(pageSize).list(); KMjg;!y
PaginationSupport ps = RKTb'3H
B0)]s<<
new PaginationSupport(items, totalCount, pageSize, `M@Ak2gcR+
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startIndex); kA#vByf`v
return ps; 6*XM7'n
} svhrf;3:
}, true); rPiNv
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} \7Cg,Xn
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public List findAllByCriteria(final ~&VN_;j_
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DetachedCriteria detachedCriteria){ &__DJ''+
return(List) getHibernateTemplate /"#4T^7&
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().execute(new HibernateCallback(){ ;vp\YIeX1
publicObject doInHibernate SUdm 0y
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(Session session)throws HibernateException { XutF"9u
Criteria criteria = w|Aqqe
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detachedCriteria.getExecutableCriteria(session); m],Ud\
return criteria.list(); %XRN]tsu
} )]Ti>R O7
}, true); pSAR/':eg
} HW_& !ye
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public int getCountByCriteria(final 3 <SqoJSp
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DetachedCriteria detachedCriteria){ 'K@0Wp
Integer count = (Integer) _sMs}?^
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getHibernateTemplate().execute(new HibernateCallback(){ _p}xZD\?,
publicObject doInHibernate zFhgE*5
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(Session session)throws HibernateException { | {P|.
Criteria criteria = F=wRkU
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detachedCriteria.getExecutableCriteria(session); [aW =
return {aDFK;qG.
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criteria.setProjection(Projections.rowCount 45+{nN[
@h?crJ6$
()).uniqueResult(); &a)vdlZSE=
} kU*{4G|6
}, true); 0Xl%uF+w
return count.intValue(); \cySWP[
} 'fW#7W
} Ka-p& Uv1<
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用户在web层构造查询条件detachedCriteria,和可选的 :Ml7G
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 9%DT0.D}$j
9y] J/1#
PaginationSupport的实例ps。 9'KonW
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ps.getItems()得到已分页好的结果集 +1`t}hO
ps.getIndexes()得到分页索引的数组 9`Q@'(m
ps.getTotalCount()得到总结果数 IB$7`7
ps.getStartIndex()当前分页索引 XB\zkf_}Xc
ps.getNextIndex()下一页索引 6Z! y
ps.getPreviousIndex()上一页索引 yp]@^T N
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 iS: #o>
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 NoDZ5Z
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一下代码重构了。 hx!7w}[A
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我把原本我的做法也提供出来供大家讨论吧: a39h P*
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首先,为了实现分页查询,我封装了一个Page类: S*t%RZ~a
java代码: h=+$>_&:
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/*Created on 2005-4-14*/ :)c80`-E
package org.flyware.util.page; ]7/gJ>g,
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/** :c8^db`"
* @author Joa m4/er539T
* Z85|I.mr
*/ La,QB3K/
publicclass Page { <y=ovkM3
e3(<8]`b[
/** imply if the page has previous page */ \"^%90F
privateboolean hasPrePage; ]((i?{jb(
`a4 $lyZ
/** imply if the page has next page */ RQ'
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privateboolean hasNextPage; ;e{5)@h$
K{DAOQ.z
/** the number of every page */ Y;Y1+jt
privateint everyPage; TSto9$}*
.[j%sGdKl
/** the total page number */ v '9m7$
privateint totalPage; AK/:I>M
wK*PD&nN
/** the number of current page */ oY3>UZ5\
privateint currentPage; 8T5k-HwE
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/** the begin index of the records by the current #Z9L_gDp
+_m r
query */ rla:<6tt
privateint beginIndex; XAD3Z?
la,
h
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/** The default constructor */ nX[;^v/
public Page(){ ZKdh%8C
Sb"2Im >
} |*\C{b
'}{?AUDx
/** construct the page by everyPage u-><}OVf~
* @param everyPage TOT
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* */ S/Oxr%H
public Page(int everyPage){ ~@9zil41
this.everyPage = everyPage; >FFVY{F
} q627<
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/** The whole constructor */ S+T|a:]\7
public Page(boolean hasPrePage, boolean hasNextPage, YoSQN/Z
@ss):FwA
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int everyPage, int totalPage, |63Y
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int currentPage, int beginIndex){ Bc
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this.hasPrePage = hasPrePage; p\D >z("
this.hasNextPage = hasNextPage; V
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this.everyPage = everyPage; =vEkMJOs
this.totalPage = totalPage; ukihx?5
this.currentPage = currentPage; r+\/G{+=}
this.beginIndex = beginIndex; n|KKby.$
} qgexb\x\4
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/** w}k B6o]
* @return ?r3e*qJGn
* Returns the beginIndex. "c
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*/ QJXdb]Y^;
publicint getBeginIndex(){ A,<@m2
return beginIndex; Rx S884
} *m&&1W_
4iBxPo(0
/** !~JWYY
* @param beginIndex 0k1MKzi Q
* The beginIndex to set. MSY N1
*/ $u5.!{Wq?
publicvoid setBeginIndex(int beginIndex){ ,nYZxYLf+
this.beginIndex = beginIndex; g
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} !-(J-45
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/** ^H!Lp[5c
* @return RV92qn
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* Returns the currentPage. d*9j77C ]
*/ i./Y w
publicint getCurrentPage(){ 3yMt1 fy
return currentPage; zJ_My&~
} B;c=eMw
.v
l="<
/** U_Y;fSl>
* @param currentPage c Vg$dt
* The currentPage to set. 8b~7~VCk
*/ qKs7WBRJy
publicvoid setCurrentPage(int currentPage){ UJwq n"Q^
this.currentPage = currentPage; u'Pn(A@1R
} 7b,AQ9
Te}IMi:
/** n|Ma&qs
* @return 05 g?jV
* Returns the everyPage. 9/H^t*5t
*/ 2K~tDNv7
publicint getEveryPage(){ d!!3"{'
return everyPage; u2om5e:
} L]NYYP-
%\ _h7:
/** J\GKqt;5@
* @param everyPage Nc:U4
* The everyPage to set. +}Auk|>Dc
*/ bY&YSlO
publicvoid setEveryPage(int everyPage){ :n`0)g[(
this.everyPage = everyPage; cWc$yE'
} -%N}A3m!5
EK.c+Or,
/** ls]Elo8h1f
* @return ~Gwas0eNa
* Returns the hasNextPage. +E `063
*/ ^
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publicboolean getHasNextPage(){ ua!D-0
return hasNextPage; a1_o.A
} H8x:D3C0
v.]'%+::#
/** 0-lPhnrp
* @param hasNextPage =b|)Wnt2f
* The hasNextPage to set. Hv+:fr"
*/ P'gT6*an,"
publicvoid setHasNextPage(boolean hasNextPage){ Dt
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this.hasNextPage = hasNextPage; yqC+P
} bmSpbX\
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/** i"ck`6v"8
* @return ]Oig..LJ
* Returns the hasPrePage. EPR(i#xU
*/ )moo?Q
publicboolean getHasPrePage(){ i:AjWC@]
return hasPrePage; R20a(4m
} 01UqDdoj
OME!W w
/** (4E.Li<O
* @param hasPrePage k?z
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* The hasPrePage to set. XtnIK
*/ 8Q#t\$RY
publicvoid setHasPrePage(boolean hasPrePage){ M^0w/
this.hasPrePage = hasPrePage; O[3q9*(
} $#g#[/
4UkP:Vz:
/** "`y W]v
* @return Returns the totalPage. \5j22L9S
* ,S7~=S
*/ DtI%-I.
publicint getTotalPage(){ }UJdE#4
return totalPage; S]Yu6FtWiO
} KE }o
HCfS)`
/** ;D%5 nnr
* @param totalPage 5)/4)0
* The totalPage to set. R.^Bxi-UG:
*/ s\F EA"w/
publicvoid setTotalPage(int totalPage){ s8/ozaeo
this.totalPage = totalPage; h$:&1jVY{
} _Ct@1}aa4x
|hZ|+7
} i2\\!s
/cn/[O9
kV]%Q3t
n?7hp%}
>Gw%r1)
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 }(f,~?CP]
={wjeRp
个PageUtil,负责对Page对象进行构造: f%(e,KgW=
java代码: :IOn`mRYu
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/*Created on 2005-4-14*/ QWIOim-
package org.flyware.util.page; e!L sc3@
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import org.apache.commons.logging.Log; 1^Y:XJ73
import org.apache.commons.logging.LogFactory; 4G68WBT
yx`r;|ds}
/** &<[]X@ bY
* @author Joa SFm.<^6
* }f0^9(
*/ !:!@dC%8_
publicclass PageUtil { ?8aWUgl
6:7:NI l:
privatestaticfinal Log logger = LogFactory.getLog y:(C=*^<t
'f$?/5@@
(PageUtil.class); Y/Gswcz
*+1"S ]YF
/** Lqf#,J
* Use the origin page to create a new page Ltq*Vcl\
* @param page NVM2\fs
* @param totalRecords E6KBpQcd[
* @return &VBD2_T
*/ #Z3I%bkw H
publicstatic Page createPage(Page page, int "e!$=;5
|^&2zyUj/
totalRecords){ VIlQzM;%^
return createPage(page.getEveryPage(), .L5T4)
/hj9Q!
page.getCurrentPage(), totalRecords); <@;xV_`X+
} nR|uAw
Am}PXj6
/** V,*0<7h
* the basic page utils not including exception 1k70>RQ&69
,`B>}
handler nm%4L
* @param everyPage d)J] Y=j
* @param currentPage OuJy$e
* @param totalRecords nr9#3Lb
* @return page pU)3*9?cIl
*/ {/VL\AW5$
publicstatic Page createPage(int everyPage, int H_nOE(i<z
tS.b5$Q
currentPage, int totalRecords){ l8
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everyPage = getEveryPage(everyPage); 3@WI*PMc
currentPage = getCurrentPage(currentPage); !gH.st
int beginIndex = getBeginIndex(everyPage, 6W#F Ss~
mDt",#g
currentPage); 6"c!tJc7j
int totalPage = getTotalPage(everyPage, K&~#@I;
FYE9&{]h
totalRecords); #z54/T
boolean hasNextPage = hasNextPage(currentPage, t6>Qe
,i((;/O6
totalPage); U JRT4>G
boolean hasPrePage = hasPrePage(currentPage); kQiW 5
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returnnew Page(hasPrePage, hasNextPage, g&(~MD2{
everyPage, totalPage, G&@RLht
currentPage, eOnl
sx/
^
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beginIndex); OG$iZiuf
} f(ec/0W
4Fc1'
privatestaticint getEveryPage(int everyPage){ 6!L*q
return everyPage == 0 ? 10 : everyPage; thboHPml{
} g,]5&C T3v
gJfL$S'w
privatestaticint getCurrentPage(int currentPage){ |4*2xDcl
return currentPage == 0 ? 1 : currentPage; -(,6w?
} ,rPyXS9Sa{
)C0X]?
privatestaticint getBeginIndex(int everyPage, int cO?"
7^e}|l
currentPage){ ialk6i![
return(currentPage - 1) * everyPage; X#C7r@H
} &!aLOx*3`
?'_7#0R_0
privatestaticint getTotalPage(int everyPage, int @Sd:]h:f-
ZpBH;{.,
totalRecords){ v-aq".XQ
int totalPage = 0; .
zMM86 c
:iC\#i]6
if(totalRecords % everyPage == 0) &\br_
totalPage = totalRecords / everyPage; ~ab_+%
else @*{BX~f
totalPage = totalRecords / everyPage + 1 ; Lj AIB(*
I,uu>-
return totalPage; { qx,X.5$
} ,H1~_|)<
wx'Tv
privatestaticboolean hasPrePage(int currentPage){ K:Go%3~,
return currentPage == 1 ? false : true; =5eDT~=2{U
} p&27|1pZm
6-YR'ikU
privatestaticboolean hasNextPage(int currentPage, ~n
9DG>a
N!~NQ-Re'
int totalPage){ $yK!Q)e:
return currentPage == totalPage || totalPage == }}Uv0g8D
4>#^Pk?Ra
0 ? false : true; ~jTnjx
} pa73`Ca]
c'qM$KN9G
/RmCMT
} Z9^$jw]
H
>{K]7D/y
.NC}TFN|
6p{x2>2y[
7rg[5hP T
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。 ,~iAoxD5jY
s~w+bwr
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 c[7qnSH
8hp]+k_y
做法如下: hj1jY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 Xlw=R2`)~
1w^[Eno$$
的信息,和一个结果集List: ~.PYS!" +
java代码: B6oAW ,3
bm.H0rHR4
zl?N1>KS
/*Created on 2005-6-13*/ es]m 6A
package com.adt.bo; xGA0]
_
9U*vnLB
import java.util.List; M(jH"u&f
RJ44o>L4O
import org.flyware.util.page.Page; dp+Y?ufr
6u}NI!he
/** I SmnZ@
* @author Joa i=+6R
*/ m`"s$\fah
publicclass Result { kv b-=
U?{j
private Page page; +pm8;&
Vba}RF[b
private List content; tPHiz%
b1cd5
/** 3!L)7Z/
* The default constructor zOw]P6Gk
*/ 9Ba<'wk/>"
public Result(){ *1n:
super(); c[$oR,2b13
} QPEv@laM
zZHsS$/
/** Dr:}k*
* The constructor using fields 5sE}B8
mF
* o<4LL7$A!
* @param page V2.K*CpZ7
* @param content `L>'9rbZO
*/ ceCshxTU
public Result(Page page, List content){ {UN z UaE
this.page = page; >Z%^|S9
this.content = content; J:(l&
}
lzuZv$K
4o8!p\a
/** s7?kU3y=s
* @return Returns the content. ?H`LrL/k
*/ )C@,mgh
publicList getContent(){ )94R\f
return content; Q8n?7JB
} i=4bY[y
1jyWP#M#
/** iR-O6*PTC
* @return Returns the page. ".u?-xcbJ
*/ :FSkXe2yy0
public Page getPage(){ `uj`ixcR
return page; 3kMiC$
} N?XN$hwdZ
|]Xw1.S.L
/** k#.co~kS
* @param content -1R~3j1_
* The content to set. C*9m `xh
*/ R&QT
'i
public void setContent(List content){ vBp5&*
this.content = content; m8?(.BJ%
} 9pgct6BO
F-Ea85/K@4
/**
0c{N)
* @param page !m;VWGl*
* The page to set. yZ{YIy~
*/ ,y.0Cb0
publicvoid setPage(Page page){ -4]6tt'G
this.page = page; =pNkS1ey
} oAL-v428
} E(oNS\4
(_T&2%
V)`?J)
A9#2.5
Dt ?Fs
2. 编写业务逻辑接口,并实现它(UserManager, qfu;X-$4
S:d `z'
UserManagerImpl) !qR(Rn
java代码: rT#QA=YB
m0 P5a%D
|'.SOm9)*
/*Created on 2005-7-15*/ mF1oY[xa_
package com.adt.service; 09"~<W8
T:ck/:ZH
import net.sf.hibernate.HibernateException; %vksN$^
ZG>OT@
GA
import org.flyware.util.page.Page; 4MIVlg9
v<)
}T5~r
import com.adt.bo.Result; |J\/U,nh
ofSOy1
/** W1OGN4`C
* @author Joa wFvilF
V
*/ 1.!(#I3
publicinterface UserManager { SlZu-4J.-
+bXZE
public Result listUser(Page page)throws D >mLSh
6/z}-;,W'
HibernateException; ;V;4#
OLi;/(g
} AL;"S;8
Li'T{0)1)
iTX.?*
E,r PM
n0m9|T&
java代码: l YhwV\3
o _-t/
?
#RSxo
4
/*Created on 2005-7-15*/ LDNpEX~
package com.adt.service.impl; }$o%^"[
=19]a
import java.util.List; r*g _
M}c_KFMV
import net.sf.hibernate.HibernateException; ^R\blJQ<^
;A C] *
import org.flyware.util.page.Page; 8RK\B%UW
import org.flyware.util.page.PageUtil; cmI8Xf]"P-
?{[H+hzz0
import com.adt.bo.Result; Dn@ n:m
import com.adt.dao.UserDAO; \-B>']:R4
import com.adt.exception.ObjectNotFoundException; u
Qj#U
m8
import com.adt.service.UserManager; vr;7p[~
)uaB^L1
/** %9Ue`8
* @author Joa qM`SN4C
*/ |joGrWv4
publicclass UserManagerImpl implements UserManager { eDm,8Se
VjnSi
private UserDAO userDAO; QSLDA`
/ [19ITZ
/** nO/5X>A,Zw
* @param userDAO The userDAO to set. $p0s
*/ C{Zv.+F
publicvoid setUserDAO(UserDAO userDAO){ _#+9)*A
this.userDAO = userDAO; ?=vwr,ir
} K%g\\uo
lojn8uL
/* (non-Javadoc) f8j^a?d|
* @see com.adt.service.UserManager#listUser m&\Gz*)3
lL^7x
(org.flyware.util.page.Page) ^?A+`1-
*/ 4rx|6NV6
public Result listUser(Page page)throws Yv;aQF"a
EAI[J&c
HibernateException, ObjectNotFoundException { A gPg0(G
int totalRecords = userDAO.getUserCount(); #=tWCxf=
if(totalRecords == 0) =_86{wlk
throw new ObjectNotFoundException F&P)mbz1
k9,"`dk@
("userNotExist"); Ac54VN
page = PageUtil.createPage(page, totalRecords); 8%"e-chd
List users = userDAO.getUserByPage(page); }lY-_y
returnnew Result(page, users); i!iODt3k
} Z/x1?{z
,i|f8pZ
} . FruI#99
0jmlsC>
IF}r%%'Y$
BO_^3Me*
WIghP5% W
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =VU2# O
O^GX Fz^
询,接下来编写UserDAO的代码: r3kI'I|bq
3. UserDAO 和 UserDAOImpl: jDnh/k0{d
java代码: X}yYBf/R`
4L0LT>'M\
)\(pDn$W
/*Created on 2005-7-15*/ #&Ee5xM=
package com.adt.dao; tFwlx3
OrBFe *2y
import java.util.List; _=] FJhO
:-Pj )Y{I
import org.flyware.util.page.Page; nAzr!$qbNv
uv5@Alm
import net.sf.hibernate.HibernateException; V*aTDU%-.
~I<y^]2{
/** EkX6> mo
* @author Joa
]Oy<zU
*/ NSq"\A\
publicinterface UserDAO extends BaseDAO { iH>djGhTh
PG!vn@b6
publicList getUserByName(String name)throws ;W].j%]Le
[OcD#~drO
HibernateException; "DpQnhvbB
lg1D>=(mY
publicint getUserCount()throws HibernateException; tTgW^&B
AMdS+(J
publicList getUserByPage(Page page)throws J$;)TI
b ~gF,^w
HibernateException; =m:W
{@A2jk\
} UwU]l17~
A=K1T]o
~'3% Qr
Q1Ao65
A3_9MO
java代码: n&]w* (,
67x^{u7
bed+Ur&
/*Created on 2005-7-15*/ BE~[%6T7
package com.adt.dao.impl; #pfosC[
e=jO_[
import java.util.List; $}$@)!-
R{_IrYk
import org.flyware.util.page.Page; ny= {V*m
S41>VbtEp
import net.sf.hibernate.HibernateException; SfUUo9R(sm
import net.sf.hibernate.Query; "=.|QKC1`
Dfia=1A
import com.adt.dao.UserDAO; qgNK!(kWpr
x(=x;X$[^
/** v=VmiBq[
* @author Joa U@nwSfp:G
*/ :8rCCop
Uv
public class UserDAOImpl extends BaseDAOHibernateImpl T"U t).
s jm79/
implements UserDAO { dL(|Y{4
|U
$-d^ZJ
/* (non-Javadoc) #1@~w}Dh
* @see com.adt.dao.UserDAO#getUserByName |m- `,
we
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(java.lang.String) Z"X*FzFo
*/ DT4RodE$
publicList getUserByName(String name)throws b_yXM
-QDgr`%5
HibernateException { 8[;oUVb5
String querySentence = "FROM user in class "~C#DZwt{
bq-\'h
f<
com.adt.po.User WHERE user.name=:name"; !`o:+Gg@
Query query = getSession().createQuery (L%q/$
T0%TeFY
(querySentence); ]bb}[#AY
query.setParameter("name", name); ]xEE7H]\h
return query.list(); ~79Qg{+]N
} 30+l0\1
mX@*2I
/* (non-Javadoc) I?Fa
* @see com.adt.dao.UserDAO#getUserCount() -i5g 8t'
*/ 9t.yP;j\Y
publicint getUserCount()throws HibernateException { sA-W^*+
int count = 0; @n*D>g
String querySentence = "SELECT count(*) FROM KxmPL
NP'Ke:
user in class com.adt.po.User"; O'|P|
Query query = getSession().createQuery tkqBCKpDa
!r
obau7
(querySentence); eZ5}O0sfp
count = ((Integer)query.iterate().next GY]6#>D#7
yVQz<tX|
()).intValue(); Sx9:$"3.X
return count; ^@L
l(?
} Ja=70ZI^6
*jw$d8q2
/* (non-Javadoc) Cmx2/N
* @see com.adt.dao.UserDAO#getUserByPage W<|K
k5QD5/Ej
(org.flyware.util.page.Page) 8pMZ~W;
*/ tr9Y1vxo{
publicList getUserByPage(Page page)throws &Z;8J @
)]?egw5l
HibernateException { m4U+,|Fa
String querySentence = "FROM user in class 0$ 9;pzr
m2q;^o:J
com.adt.po.User"; a05:iFoJ
Query query = getSession().createQuery w[7.@ %^[
|+xtFe
(querySentence); Q=L$7
query.setFirstResult(page.getBeginIndex()) ElR&scXi__
.setMaxResults(page.getEveryPage()); Rk jKIa
return query.list(); q\'P1~
} Y:!/4GF
ddq 1NW
} N!Wq}#&l
kH8$nk eev
?WQd
r>:L$_]L
A6UdWK
至此,一个完整的分页程序完成。前台的只需要调用 )Z8"uRTb0
YUVc9PV)Ws
userManager.listUser(page)即可得到一个Page对象和结果集对象
J"Y
Uq]EJu
的综合体,而传入的参数page对象则可以由前台传入,如果用 _{*$>1q
8LQ59K_WX
webwork,甚至可以直接在配置文件中指定。 tk)>CK11
5} MlZp
下面给出一个webwork调用示例: ]Z$TzT&@%
java代码: ()nKug`.@
zJuRth)(,
h%1~v$W`
/*Created on 2005-6-17*/ N5f0|U&
package com.adt.action.user; 6a%:zgkOpu
@W1WReK]f
import java.util.List; uH
ny ]
_/jUs_W
import org.apache.commons.logging.Log; o[6vxTH
import org.apache.commons.logging.LogFactory; 0/SC
import org.flyware.util.page.Page; e>,9]{N+$
+Y5(hjE
import com.adt.bo.Result; dE5 5
import com.adt.service.UserService; ,a9D~i 9R
import com.opensymphony.xwork.Action; QxL@'n#5
T\2) $
/** @[5_C?2
* @author Joa o%Uu.P
*/ `CAG8D
publicclass ListUser implementsAction{ O>SuZ>g+7
J})$
privatestaticfinal Log logger = LogFactory.getLog oN[Fz a>
rq<`(V'2
(ListUser.class); nIV.9#~&
'0R/6Z|/Y
private UserService userService; g{A3W) [ b
5:*5j@/S
private Page page; %z-dM` i
[}A_uOGEP
privateList users; ?jNF6z*M6
9feD!0A
/* &*(n<5wt
* (non-Javadoc) Pn'`Q S?
* #$rf-E5g-K
* @see com.opensymphony.xwork.Action#execute() `d}W;&c
*/ rPiiC/T.`
publicString execute()throwsException{ ilDJwZg#
Result result = userService.listUser(page); 5E]UI YAkV
page = result.getPage(); < 72s7*Rv
users = result.getContent(); NK+FQ^m[
return SUCCESS; oF%^QT"R
} u;+%Qh
/e.FY9
/** ]PR|d\O
* @return Returns the page. r +p@X
*/ PoYr:=S?
public Page getPage(){ Wk/fB0
return page; ELN|;^-/|Q
} uIYcmF\?
/{fZH,!L
/** 9"WRI Ht'c
* @return Returns the users. !(W[!%
*/ J*}VV9H
publicList getUsers(){ #C"7
l6'a
return users; r> Fec
} -,R0IGS
jv*Dg (
/** 536^PcJlN
* @param page sEoZ1E
* The page to set. *w=z~Jq^R"
*/ D8k*0ei&
publicvoid setPage(Page page){ VKT@2HjNT`
this.page = page; |2qR^Hd&5
} !c\7
'GrRuT<
/** .KFA218h*x
* @param users XXXljh6
* The users to set. k|^vCZ<(x
*/ Xf6fH O
publicvoid setUsers(List users){ 3|q2rA
this.users = users; Lqg]Fd
} 6e,Apj 0
W7%p^;ZQ$
/** O-i4_YdVt
* @param userService Pg7>ce
* The userService to set. +VwV5iy[`
*/ +z+F-
publicvoid setUserService(UserService userService){ +:}kZDl@ X
this.userService = userService; s jSi;S4
} E
yd$fcRK
} v,n);
6@&fvf
1d`cTaQ-
&xgZFSq
jz|VF,l
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ,cLH*@
sD{j@WEZ
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 miwf&b
%WZ$]M?q
么只需要: u',b1 3g(
java代码: ^Fn%K].X
6Ux[,]GK
aUAcRW
<?xml version="1.0"?> [@ILc*2O
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork V)=Z6 ti
*E.LP1xP
1.0//EN" "http://www.opensymphony.com/xwork/xwork- lBS"3s384
v3-5"q!Sq
1.0.dtd"> k<!<<,Z
TM)u?t+[
<xwork> vlvvi()
UnP|]]o:I
<package name="user" extends="webwork- [8.-(-/;
oI*d/*
interceptors"> ,'=hjIel
UAdz-)$
<!-- The default interceptor stack name axtb<5&
0',[J
--> w#sq'vo4%
<default-interceptor-ref @$oZ|ZkZ
r|<6Aae&
name="myDefaultWebStack"/> w=|py>%
.8K6C]gw
<action name="listUser" Q<1L`_.>
-;vT<G3
class="com.adt.action.user.ListUser"> qIz}$%!A
<param 0t+])>
EsTB(9c?
name="page.everyPage">10</param> z{=v)F5y
<result 0Q`&inwh
)(lJT&e
name="success">/user/user_list.jsp</result> drI\iae{^
</action> :G#KB'
+mLD/gK`
</package> C s#w72N
=HS4I.@c_5
</xwork> F_v-}bbcFQ
$~G@
_$5@uL{n"^
NJm-%K
-x{&an=
z+
ZG1\
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 e^8BV;+c
ws[/
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 4gb'7'
#|?8~c;RWG
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 j;+["mi
Yz\
N&0"
|mOMRP#'
!W
/C[$E
F,&