Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 &+oJPpHi\
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .v+J@Y a
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 (8o;Cm
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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 eDNY|}$}v
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。 D( TfW
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分页支持类: >nK (
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java代码: TBF{@{.d
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package com.javaeye.common.util; w+!V,lU"^
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import java.util.List; "av/a
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publicclass PaginationSupport { ^n4aoj
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publicfinalstaticint PAGESIZE = 30; xZV|QVY;
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privateint pageSize = PAGESIZE; r<P? F
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privateList items; |6Iw\YU
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privateint totalCount; o?.VW/"
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privateint[] indexes = newint[0]; _wW"Tn]
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privateint startIndex = 0; \sW>Y#9]
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public PaginationSupport(List items, int F<2gM#jLB
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totalCount){ k#mL4$]V5N
setPageSize(PAGESIZE); UA0(
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setTotalCount(totalCount); k4:=y9`R}$
setItems(items); bsI?=lO
setStartIndex(0); LT,zk)5
} { M[iYFg=
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public PaginationSupport(List items, int %,Y^Tp
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totalCount, int startIndex){ cauKG@:2F
setPageSize(PAGESIZE); 7eZwpg?K
setTotalCount(totalCount); Tn>L?
setItems(items); qCm%};yt
setStartIndex(startIndex); md : Wx
} DC$> 5FDv
j \ #y
public PaginationSupport(List items, int w/(2fU (
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totalCount, int pageSize, int startIndex){ O=!Eqa ExW
setPageSize(pageSize); LR"7e
setTotalCount(totalCount); &oK&vgcj
setItems(items); }1sd<<\`
setStartIndex(startIndex); $O\]cQD`u
} N#:W#C{16w
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publicList getItems(){ poi39B/Vt
return items; /" &Jf}r
} \C1`F[d_
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publicvoid setItems(List items){ i(q a'*
this.items = items; Fj<a;oV
} 9Z3Y, `R,
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publicint getPageSize(){ LN'})CI8m
return pageSize; WO+>W+|N
} (|y@ftr@
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publicvoid setPageSize(int pageSize){ nqcD#HUv
this.pageSize = pageSize; Et)j6xz/F
} reoCyP\!!
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publicint getTotalCount(){
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return totalCount; lOIf4
} -li;w
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hN;$'%^
publicvoid setTotalCount(int totalCount){ Thp!X/2O`
if(totalCount > 0){ 8)}A}x
this.totalCount = totalCount; +/#Lm#*nu%
int count = totalCount / $1D>}5Ex
FJsg3D*@J
pageSize; ?SoRi</1
if(totalCount % pageSize > 0) hBW,J$B
count++; p;2NO&
indexes = newint[count]; [Ue"#w
for(int i = 0; i < count; i++){ :&O6Y-/B
indexes = pageSize * @Y&(1Wl
wF['oUwHH
i; G\r>3Ys
} t@BhosR-
}else{ c 9zMI
this.totalCount = 0; o{K#LP
} Gii1|pLZ1
} ~NwX,-ri
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publicint[] getIndexes(){ 82=>I*0Q
return indexes; mH4Jl1S&
} 59a7%w
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publicvoid setIndexes(int[] indexes){ 0tN/P+!|
this.indexes = indexes; p=f8A71
} _^] :tL6
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publicint getStartIndex(){ XZpF<7l
return startIndex; %4h$/~
} f\vg<lca
<cR]-Yr~
publicvoid setStartIndex(int startIndex){ PZCOJK
if(totalCount <= 0) t|k-Bh:x
this.startIndex = 0; rqi|8gKY
elseif(startIndex >= totalCount) 9$N~OZ;-*x
this.startIndex = indexes ?_G?SQ
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[indexes.length - 1]; zVtNT@1K>u
elseif(startIndex < 0) tc)4$"9)
this.startIndex = 0; VrZ6m
else{ ?\T):o;/
this.startIndex = indexes ?h|w7/9
gn4Sz")
[startIndex / pageSize]; 2S_7!|j
} VaFv%%w
} H=>;Mj
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publicint getNextIndex(){ :|E-Dx4F6H
int nextIndex = getStartIndex() + X!/
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pageSize; Qj/.x#T
if(nextIndex >= totalCount) WB>M7MI%
return getStartIndex(); ^CQVqa${]
else c *]6>50
return nextIndex; B)(ZRH
} H83/X,"!w
){ ,v&[
publicint getPreviousIndex(){ 8>~\R=SC
int previousIndex = getStartIndex() - JnZlz?}^
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pageSize; |H@1g=q
if(previousIndex < 0) YW UCrnr
return0; *lws7R
else d^YM@>%
return previousIndex; |a[Id
} Cdbh7
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} KZt4 dr
}6^d/nE*T
Oxhc!9F
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抽象业务类 aMycvYzH
java代码: wT+b|K
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/** !Won<:.[0
* Created on 2005-7-12 h(wu5G0C#u
*/ x$
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package com.javaeye.common.business; d#]XyN>
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import java.io.Serializable; u'Ua ++a\
import java.util.List; &KZr`"cT#
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import org.hibernate.Criteria; |oI]
import org.hibernate.HibernateException; $bT<8:g
import org.hibernate.Session; P% ZCACzV
import org.hibernate.criterion.DetachedCriteria; OKp0@A)8
import org.hibernate.criterion.Projections; {Kkut?5
import 2YL)"
w
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org.springframework.orm.hibernate3.HibernateCallback; d~-Cr-s4
import VygiR|f-
kw Iw=8q~
org.springframework.orm.hibernate3.support.HibernateDaoS exQU
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upport; 2wki21oY
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import com.javaeye.common.util.PaginationSupport; [#Y7iN&
&>&UqWL
public abstract class AbstractManager extends D4fHNk)kZ
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HibernateDaoSupport { ES&"zjr$
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privateboolean cacheQueries = false; @mB*fl?-
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privateString queryCacheRegion; !E+. (
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publicvoid setCacheQueries(boolean Tf1G827
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cacheQueries){ G`1FD
this.cacheQueries = cacheQueries;
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} :yTpjC-S]
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publicvoid setQueryCacheRegion(String "<y0D!&
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queryCacheRegion){ ;j]-;wg-;
this.queryCacheRegion = 9e*v&A2Y'
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queryCacheRegion; `swf~
} ya^zlj\`0e
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publicvoid save(finalObject entity){ c0%.GcF0{
getHibernateTemplate().save(entity); W%bzA11l
} p#eai
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publicvoid persist(finalObject entity){ wZ_k]{J
getHibernateTemplate().save(entity); `/0S]?a.{B
} ;Iu}Q-b*
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publicvoid update(finalObject entity){ Rt^~db
getHibernateTemplate().update(entity); O!7v&$]1
} AQH\ ;L
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publicvoid delete(finalObject entity){ L6-zQztn
getHibernateTemplate().delete(entity); g_l=z`,8
} ~jDG&L
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publicObject load(finalClass entity, ~ojH$=K>d
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finalSerializable id){ 7;T6hKWV[
return getHibernateTemplate().load JXKqQxZ[X
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(entity, id); r#xq 8H=_m
} cU^Z=B
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publicObject get(finalClass entity, Pl}>
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finalSerializable id){ TzJp3
return getHibernateTemplate().get pSvqGJU3
vl{G;[6
(entity, id); 4._U
} pW>?%ft.
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publicList findAll(finalClass entity){ *)6:yn
return getHibernateTemplate().find("from O~1vX9
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" + entity.getName()); 6/Pw'4H9$
} hrRkam !y
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publicList findByNamedQuery(finalString t69C48}15
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namedQuery){ |H LU5=Y
return getHibernateTemplate xKl!{A9$w
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().findByNamedQuery(namedQuery); ,o3{?o]s
} >*hY1@N1
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publicList findByNamedQuery(finalString query, SGuLL+|W#8
*C(/2
finalObject parameter){ cM= ?{W7~
return getHibernateTemplate |NsrO8H
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().findByNamedQuery(query, parameter); /i${ [1
} p%8v+9+h2
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publicList findByNamedQuery(finalString query, ?'@tx4#v\2
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finalObject[] parameters){ VKjDK$
return getHibernateTemplate }5 2]
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().findByNamedQuery(query, parameters); @w H+,]xE
} Vh WF(*
@.PVUP
publicList find(finalString query){ lBbUA)z6
return getHibernateTemplate().find Z;nbnRz
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(query); SP,#KyWP0)
} \
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publicList find(finalString query, finalObject o:E_k#Fi
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parameter){ ?x*Ve2+]
return getHibernateTemplate().find 7~2/NU?
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(query, parameter); ]Tb ?k+a
} Vh.9/$xQ
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public PaginationSupport findPageByCriteria rM
sd)
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(final DetachedCriteria detachedCriteria){ V8aLPJ0_
return findPageByCriteria ((2 g
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 2W}f|\8MX
} 3M;[.b
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public PaginationSupport findPageByCriteria {Q&@vbw'
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(final DetachedCriteria detachedCriteria, finalint Y55Yo5<j/+
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startIndex){ cZ!%#Az
return findPageByCriteria cWd\Ki
9WJS.\G^
(detachedCriteria, PaginationSupport.PAGESIZE, DPU%4te
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startIndex); DP(JsZ}
} !L+4YA
#hA]r.
public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint b"au9:F4@7
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pageSize, HG1)q\Xd
finalint startIndex){ syEWc(5
return(PaginationSupport) 4oY<O
#s'UA!)
getHibernateTemplate().execute(new HibernateCallback(){ 36NENzK
publicObject doInHibernate JAjXhk<=
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(Session session)throws HibernateException { 986y\9Zu
Criteria criteria = "Y9PS_u(~
}`O_
detachedCriteria.getExecutableCriteria(session); }mz6z<pJ_
int totalCount = our$Ka31
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((Integer) criteria.setProjection(Projections.rowCount e~Oge
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()).uniqueResult()).intValue(); ^yO+-A2zC
criteria.setProjection wkO8
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(null); igoXMsifT+
List items = Ft7{P.g
z!z+E%H^
criteria.setFirstResult(startIndex).setMaxResults (&25 8i,
{^r8uKo:~
(pageSize).list(); q8 j
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PaginationSupport ps = FC' v= *
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new PaginationSupport(items, totalCount, pageSize, W[5a'}OV
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startIndex); /M:R|91:_
return ps; h
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} n9Mi?#xIp
}, true); {,Y?+F
} e|`QW|9 .
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public List findAllByCriteria(final Dr;-2$Kt/&
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DetachedCriteria detachedCriteria){ c$cb2V7,
return(List) getHibernateTemplate u?OyvvpH
B.wRZDEvc
().execute(new HibernateCallback(){ VtNY~
publicObject doInHibernate :YL`GSl
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(Session session)throws HibernateException { !`u
Criteria criteria = SDdefB
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detachedCriteria.getExecutableCriteria(session); ~1x,m.f8
return criteria.list(); cULASS`,
} 6`KAl rH
}, true); [D]9M"L,vQ
} HFJna2B`
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public int getCountByCriteria(final On[:]#
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DetachedCriteria detachedCriteria){ "pb$[*_@$
Integer count = (Integer) YbMeSU/sX
q*^Y8s~3I
getHibernateTemplate().execute(new HibernateCallback(){ .qjVw?E
publicObject doInHibernate yPgDb[V+
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(Session session)throws HibernateException { n*tT<
Criteria criteria = J&64tQl*
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detachedCriteria.getExecutableCriteria(session); 8hx4s(1!
return 0!WF,)/T7i
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criteria.setProjection(Projections.rowCount K~j&Q{yws@
5dH}cXs
()).uniqueResult(); 0KW@j>=jK
} zJp}JO
}, true); R)>/P{A-P
return count.intValue(); QZcdfJck=+
} GpjyF_L
} '@Zau\xC
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用户在web层构造查询条件detachedCriteria,和可选的 4!'1o`8vs
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $T\W'WR>
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PaginationSupport的实例ps。 D&Xh|}2A
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ps.getItems()得到已分页好的结果集 _ >)+
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ps.getIndexes()得到分页索引的数组 P\;L#2n
ps.getTotalCount()得到总结果数 L5%t.7B
ps.getStartIndex()当前分页索引 7H$0NMP
ps.getNextIndex()下一页索引 TU6e,G|t
ps.getPreviousIndex()上一页索引 ^;";fr
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 AT){OQF8&
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 c/l%:!A
LRF_w)^['
一下代码重构了。 X<\E
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我把原本我的做法也提供出来供大家讨论吧: >]6f!;Rt
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首先,为了实现分页查询,我封装了一个Page类: :%[=v(G[
java代码: "N"$B~W*
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/*Created on 2005-4-14*/ \8Mn[G9TL
package org.flyware.util.page; x-wIgo+
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/** MAhJ>qe8
p
* @author Joa k[TVu5R
* mAycfa
*/ ^SP/&w<c
publicclass Page { cE{hy7cH
XILB>o.^3
/** imply if the page has previous page */ _a;E>
privateboolean hasPrePage; S6k
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/** imply if the page has next page */ 3AKT>Wy =
privateboolean hasNextPage; 'r&az BO
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/** the number of every page */ v"nN[_T
privateint everyPage;
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r57&F`{
/** the total page number */ *&WkorByW
privateint totalPage; #BB,6E
^?pf.E!F`
/** the number of current page */ ;[-OMGr]#
privateint currentPage; <evvNSE
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/** the begin index of the records by the current +iS'$2)@
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query */ |u r/6{Oj1
privateint beginIndex; L-&N*
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e
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/** The default constructor */ 7_OC&hhL
public Page(){ ^!Y]l
y^PQgzm]
} d:Y!!LV-@L
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/** construct the page by everyPage @vsgmz
* @param everyPage cB$OkaG#
* */ #'poDX?
public Page(int everyPage){ z\S#P|;
this.everyPage = everyPage; 0c2O'&$au
} ~m/nV81
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/** The whole constructor */ A
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public Page(boolean hasPrePage, boolean hasNextPage, ew13qpt)<L
x)35}mi){L
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int everyPage, int totalPage, a
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int currentPage, int beginIndex){ j6!C/UgQ
this.hasPrePage = hasPrePage; "_LDs(&
this.hasNextPage = hasNextPage; Rz sgPk
this.everyPage = everyPage; o,-p[1b
this.totalPage = totalPage; ;rgg O0Y
this.currentPage = currentPage; jeKqS
this.beginIndex = beginIndex; |j 9d.M
} <z'Pj7c[
sj9j47y
/** FEC`dSTI
* @return %G'{G
* Returns the beginIndex. csh@C
ckC8
*/ lN(|EI
publicint getBeginIndex(){ z3n273W>6
return beginIndex; hgYi ,e
} 0V RV.Ml
jHPkfwfAF
/** *B4?(&0
* @param beginIndex 'E\/H17
* The beginIndex to set. [Rj_p&'
*/ ^sF/-/ {?U
publicvoid setBeginIndex(int beginIndex){ {l
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this.beginIndex = beginIndex; yH=Hrz:<eM
} q8m{zSr
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/** (vR9vOpJ
* @return F"-u8in`
* Returns the currentPage. FTF`-}Hz
*/ l|kGp~
publicint getCurrentPage(){ ftb .CPWI
return currentPage; T!f+H?6
} 8"'Z0
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/** D(;jv= "/
* @param currentPage u=6LPwiI
* The currentPage to set. \m xi8Z
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*/
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publicvoid setCurrentPage(int currentPage){ {"dvU"y)\
this.currentPage = currentPage; 2_/H,
} lXT+OJF
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/** [Qw BSq8)
* @return <`Xt?K
* Returns the everyPage. ^P!(*k#T
*/ JT,[;
publicint getEveryPage(){ ;s$,}O.
return everyPage; 9ZD>_a
} +^6a$ N
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/** ts:YJAu+F
* @param everyPage Jkx_5kk/\
* The everyPage to set. r"_U-w
*/ ^ g'P
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publicvoid setEveryPage(int everyPage){ |j2$G~B6
this.everyPage = everyPage; 7DZZdH$Fm
} YHp]O+c
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/** ]lqe,>
* @return (v,g=BS,
* Returns the hasNextPage. ;hgRMkmz4<
*/ 9cIKi#Bl
publicboolean getHasNextPage(){ p!o?2Lbiw
return hasNextPage; F(;=^w
} e"d-$$'e
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/** -=InGm\Y
* @param hasNextPage 20,}T)}Tm
* The hasNextPage to set. <#ng"1J
*/ cU|tG!Ij?
publicvoid setHasNextPage(boolean hasNextPage){ 1CR)1H
this.hasNextPage = hasNextPage; F"^/R
} f-BPT2U+
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/** ,%T
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* @return PL|ea~/
* Returns the hasPrePage. f
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*/ K^Ho%_)
publicboolean getHasPrePage(){ 4n0Iw I
return hasPrePage; v.6K;TY.
} iu iVr$E
.[:y`PCF
/** 5v[2R.eT-
* @param hasPrePage nIqNhJ+
* The hasPrePage to set. ts/Ha*h
*/ 6hO]eS
publicvoid setHasPrePage(boolean hasPrePage){ S}3?
this.hasPrePage = hasPrePage; c6Z"6-}$
} xU F5
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/** W_L;^5Y;m
* @return Returns the totalPage. Y`*h#{|
* {nj`>
*/ <u}[_
publicint getTotalPage(){ 3kavzB[
return totalPage; v05$"Ig
} _Wtwh0[r*
0i>>CvAl}
/** em9nuXG
* @param totalPage V`4/oM`
* The totalPage to set. Gm[XnUR7V
*/ C/!7E:
publicvoid setTotalPage(int totalPage){ 'j\~> a3\
this.totalPage = totalPage; bo-lT-I
} ]64pb;w"$D
=eQ'^3a
} HE:]zH
(&1565
6(/*E=bOKV
ID~}pEQ
fD*jzj7o,
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 &S=xSs:q.
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个PageUtil,负责对Page对象进行构造: P>hR${KE
java代码: Hyb_>n
fp?/Dg"49.
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/*Created on 2005-4-14*/ 9*S9~
package org.flyware.util.page; cDq*B*e
0"l`M5-KP
import org.apache.commons.logging.Log; +' SG$<Xv
import org.apache.commons.logging.LogFactory; &<EixDi4q
6f^IAa|
/** M%bD7naBq
* @author Joa ?h:xO\h8
* |~B` [p]5H
*/ {n{-5Y
publicclass PageUtil { S|O#KE
ap<r)<u
privatestaticfinal Log logger = LogFactory.getLog D$Ao-6QE
W
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(PageUtil.class); 1Q7]1fRu
%-L
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/** d^Rea8
* Use the origin page to create a new page m[nrr6 G"
* @param page o|APsQE
* @param totalRecords ;)Sf|
* @return |`' WEe2
*/ K(AZD&D
publicstatic Page createPage(Page page, int Z3f}'vr
dN@C)5pm5`
totalRecords){ UHS"{%
return createPage(page.getEveryPage(), K$wxiGg8P
L=gG23U&
page.getCurrentPage(), totalRecords); @CS%=tE}U
} #kgLdd"
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pil
/** \s6VOR/
* the basic page utils not including exception *-&+;|mM
L]E.TvM1*
handler oxug
* @param everyPage L|p+;ex
* @param currentPage 24k;.o
* @param totalRecords Bo;{ QoB
* @return page
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*/ ,+v>(h>q
publicstatic Page createPage(int everyPage, int ^;[^L=}8$
|Es,$
currentPage, int totalRecords){ gkDXt^Ob
everyPage = getEveryPage(everyPage); rQ(u@u;
currentPage = getCurrentPage(currentPage); C[CNJ66
int beginIndex = getBeginIndex(everyPage, $ve*j=p
PY#_$ C
currentPage); BD [<>Wm
int totalPage = getTotalPage(everyPage, aWY#gI{
y
m?uj4I{
totalRecords); h>A~yDT[
boolean hasNextPage = hasNextPage(currentPage, sC_doh_M
CUx-k|\
totalPage); GQYB2{e>
boolean hasPrePage = hasPrePage(currentPage); 1-.(pA'
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returnnew Page(hasPrePage, hasNextPage, L0*f(H
everyPage, totalPage, ++BQ==@
currentPage, 2p~G][
@2sr/gX^
beginIndex); 71Y3.1+
} Pu(kCH{
;Q<2Y#
privatestaticint getEveryPage(int everyPage){ v!#koqd1y.
return everyPage == 0 ? 10 : everyPage; _$yS4= .
} @v/
8}n
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privatestaticint getCurrentPage(int currentPage){ e\}'i-
return currentPage == 0 ? 1 : currentPage; \)cbg#v
} 9O\yIL
/d>Jkv
privatestaticint getBeginIndex(int everyPage, int dB8 e
@&GY5<&b
currentPage){ #e[igxwi
return(currentPage - 1) * everyPage; 91UC>]}H
} e"ClG/M_XS
gRwRhA/
privatestaticint getTotalPage(int everyPage, int lr=quWDY
!Y*O0_
totalRecords){ Y8/&1s_
int totalPage = 0; u6
4{w,
p+CK+m
if(totalRecords % everyPage == 0) !gi3J @
totalPage = totalRecords / everyPage; d!y_N&z|(
else {( Ba
totalPage = totalRecords / everyPage + 1 ; e!w#{</8Q
i<!1s%i}
return totalPage; T/tC X[}
} C#.27ah
G4%dah 5
privatestaticboolean hasPrePage(int currentPage){ }x:}9iphF
return currentPage == 1 ? false : true; J!H)[~2/
} _xM3c&VeG
7b(r'b@N
privatestaticboolean hasNextPage(int currentPage, $Zj3#l:rK
@eP(j@(^
int totalPage){ 8aVj@x$'
return currentPage == totalPage || totalPage == Z& bIjp
fz%e?@>q
0 ? false : true; 0NXaAf:2Z
} '\P+Bu]6&
[6%y RQ_
?+L7Bd(EF%
} Mlo:\ST|
)Mh5q&ow
{"_V,HmEF+
]:Pkh./
1n#{c5T
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 )H{OqZZYD
w +HKvOs5c
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 *s?C\)x
yS4nB04`=
做法如下: `m\ ?gsw7
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %V92q0XW
x) R4_3
的信息,和一个结果集List: )jMk~;'r
java代码: Zig3WiD&
+XAM2uN5_.
fwSI"cfM
/*Created on 2005-6-13*/ uExYgI`<%&
package com.adt.bo; [pz1f!Wn
v"dl6%D"
import java.util.List; B
\.05<
US&:UzI.
import org.flyware.util.page.Page; B~%SB/eu
>~uKkQ_p
/** ! ~+mf^D
* @author Joa O>IG7Ujl
*/ "Jg*
/F
publicclass Result { d V3R)
T5aeO^x
private Page page; )_K:A(V>
X`7O%HiX/`
private List content; Hm_&``='
=j8g6# 'u
/** uy([>8uu
* The default constructor p%5(Qqmlk
*/ .19_EQ>+
public Result(){ hmv*IF.
super(); BWzo|isv
} GX N:=
"SpsSQ
/** 6}:(m#+
* The constructor using fields q ;e/gP2
* @Dd3mWKq
* @param page WISeP\:^
* @param content *-s':('R
*/ +`TwBN,kp-
public Result(Page page, List content){ p9eTrFDy?
this.page = page; nu6v@<<F>
this.content = content; [-1Yyy1}
} ]F4|@+\9
Jg@eGs\*
/** ORt)sn&~d
* @return Returns the content. U-#vssJhk
*/ ]u%Y8kBe
publicList getContent(){ wfM|3GS+.
return content; dEfP272M
} 8%;]]{(B
h[gKyxZ/t
/** &usum~@
* @return Returns the page. VB~Do?]*k%
*/ 3MoVIf1
public Page getPage(){ yXro6u?rC
return page; r?WOum
} 8VMD304
"O%xQ N
/** p:Zhg{sF
* @param content jC'Diu4|Q
* The content to set. 5,du2
*/ vH{JLN2
public void setContent(List content){ V4|l7
this.content = content; IKnXtydeI}
} #|6M*;l N|
t8Giv89{
/** 3EyVoS6D
* @param page m"vWu0/#
* The page to set. uD4$<rSHb
*/ l6-%)6u>
publicvoid setPage(Page page){ j8?rMD~
this.page = page;
JjHQn=3AJ
} ?YnB:z*eV
} Edl .R}&1
zC!Pb{IaH
\C`2z]V%
t,qz%J&a
4M>E QF&
2. 编写业务逻辑接口,并实现它(UserManager, Y^'mBM#j
0|~3\e/QV
UserManagerImpl) m"~),QwF9
java代码: ptTp63+
BtKbX)R$J
Ml+O -
3T
/*Created on 2005-7-15*/ Ce_l\J8G
package com.adt.service; 3$ BYfI3H
j8ag}%
import net.sf.hibernate.HibernateException; }z_7?dn/
KOD%>+vG$
import org.flyware.util.page.Page; Wq*W+7=.
FMAt6HfU
import com.adt.bo.Result; n#)kvr
vFsl]|<;8
/** ^-K~y
* @author Joa t/a
*/ t<znz6
publicinterface UserManager { }E\u2]
u]Dds;~"b
public Result listUser(Page page)throws $%5!CD1)
DZV U!J
HibernateException; oqy}?<SQ
Q5tx\GE
} e `Tssa+
O+o_{t\R
=kn-F T
\>
/@]@Tz@'
java代码: pAc "Wo(Q
p}h9>R
rTM0[2N
/*Created on 2005-7-15*/ o`\@Yq$.
package com.adt.service.impl; (?~*.g!
[2nPr^
import java.util.List; A]OVmw
*@[+C~U
import net.sf.hibernate.HibernateException; 6q~*\KRk
Y> PC>
import org.flyware.util.page.Page; IJofbuzw:
import org.flyware.util.page.PageUtil; Nrk/_0^
Eb9{
import com.adt.bo.Result; hB-<GGcO <
import com.adt.dao.UserDAO; M}`G}*
import com.adt.exception.ObjectNotFoundException; Z;J{&OJ3qM
import com.adt.service.UserManager; (c9!:
@]B
7(j<'R
/** C9E@$4*
* @author Joa Ozs&YZ
*/ t}-rN5GO
publicclass UserManagerImpl implements UserManager { R?+:Js/
H?j!f$sw
private UserDAO userDAO; K_LwYO3
=s1Pf__<k
/** #[NNb?`F
* @param userDAO The userDAO to set. JiCy77H
*/ rqYx\i?
publicvoid setUserDAO(UserDAO userDAO){ !!UQ,yU
this.userDAO = userDAO; x|<89o
L
} @3I/57u<
\k*h& :$
/* (non-Javadoc) S s#UX_DT_
* @see com.adt.service.UserManager#listUser IT\
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(org.flyware.util.page.Page) f`8mES'gc8
*/ "SN+ ^`
public Result listUser(Page page)throws 5tl uS
HDT-f9%}<4
HibernateException, ObjectNotFoundException { D^\2a;[AxA
int totalRecords = userDAO.getUserCount(); 2V =bE-
if(totalRecords == 0) "3:TrM$|A
throw new ObjectNotFoundException $7bux1L
f)!7/+9>
("userNotExist"); %R LGO&
page = PageUtil.createPage(page, totalRecords); f2RIOL,
List users = userDAO.getUserByPage(page); o:Q.XWa@MG
returnnew Result(page, users); ?FwjbG<
} Af7&;8pM
HU+zzTgI
} wT-@v,$
rgXD>yu(
K^+}__;]
J9yB'yE8
?u_O(eg
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #Vh$u%q3
~F=,)GE
询,接下来编写UserDAO的代码: odC}RdN
3. UserDAO 和 UserDAOImpl: +a((,wAN2
java代码: #gY|T|
0@dN$e
f3HleA&&
/*Created on 2005-7-15*/ xEvm>BZi
package com.adt.dao; T&~7*j(|e
xl;0&/7e
import java.util.List; 9!|+GIjn
@mId{w z
import org.flyware.util.page.Page; My JG2C#R
6pY<,7t0
import net.sf.hibernate.HibernateException; Y'v;!11#
D'3. T{*rH
/** R3Ka^l8R|
* @author Joa < .B^\X$
*/ _=;lt O
publicinterface UserDAO extends BaseDAO { Ug,23
zV"oB9\9O
publicList getUserByName(String name)throws j9/Ev]im|F
$yg=tWk
HibernateException; 61{IXx_
om}jQJ]KH
publicint getUserCount()throws HibernateException; \cRe,(?O
gTjhD(
publicList getUserByPage(Page page)throws /yS/*ET8
!E|k#c9
HibernateException; bjYaJtn
#Do#e
{=+
} 2OQDG7#Kc
B!zqvShF
W;@9x1jKX
,=Fn6'
yCG<qQz
java代码: @%sr#YqY
auT'ATW7i
|=W=H6h*
/*Created on 2005-7-15*/ hCKx%&[^7
package com.adt.dao.impl; JOm6Zc
zS+_6s
import java.util.List; R x.]m0
{f<\`
import org.flyware.util.page.Page; K JX@?1"
J,=:
]t
import net.sf.hibernate.HibernateException; bD;c>5t
import net.sf.hibernate.Query; 2>!?EIE7
EU"J'?
import com.adt.dao.UserDAO; Y94/tjt
&33.mdBH
/** nlkQ'XGAI
* @author Joa eq#x~O4
*/ -L%2*`-L$
public class UserDAOImpl extends BaseDAOHibernateImpl ~M4@hG!
uepL"%.@7|
implements UserDAO { ]h6mJ{k
T11;LSD
/* (non-Javadoc) K0Zq)<
* @see com.adt.dao.UserDAO#getUserByName ;&%G)f
|ZnRr
(java.lang.String) |U4t 8
*/ I{0bsTp;
publicList getUserByName(String name)throws 9x40
78i"3Tm)w
HibernateException { Hz6yy*
String querySentence = "FROM user in class }th^l*g
}475c{
com.adt.po.User WHERE user.name=:name"; @lnM%
Query query = getSession().createQuery 3!V$fl0
p/f!\
(querySentence); b-XC\
query.setParameter("name", name); wuQ>|\Zs
return query.list(); XgmblNp1
} bb^$]lT'
P.;S6i
n
/* (non-Javadoc) e;/C}sK:
* @see com.adt.dao.UserDAO#getUserCount() IAJYD/Y&?
*/ A->y#KQ
publicint getUserCount()throws HibernateException { 'F[ C 4
int count = 0; +#d}3^_]
String querySentence = "SELECT count(*) FROM 6b8@6;&LI
0piBK=tE/
user in class com.adt.po.User"; X)TUKt
Query query = getSession().createQuery _7M! b9oA
ToB^/
n[
(querySentence); 5@{+V!o,
count = ((Integer)query.iterate().next ]O;Hlty(g
8{GRrwQ>
()).intValue(); 23;e/Qr
return count; .V\M/q\Tv
} !dW77kLTg
Hw "UJP
/* (non-Javadoc) H~P"uYKIZ
* @see com.adt.dao.UserDAO#getUserByPage -MqWcB9&
C,!}WB@VME
(org.flyware.util.page.Page) k9^Vw+$m
*/ #Rkld v'
publicList getUserByPage(Page page)throws )
-C9W7?I
XI*_ti
HibernateException { DB>Y#2j4h
String querySentence = "FROM user in class {&Bpf
K;`)
;\$P;-VY
com.adt.po.User"; /@.c
59r
Query query = getSession().createQuery Q:x:k+O-
~BVK6
(querySentence); h!*++Y?&0
query.setFirstResult(page.getBeginIndex()) !j3V'XU#Zn
.setMaxResults(page.getEveryPage()); yT>t[t60/S
return query.list(); Q l$t
} r12{XW?~
f~.w2Cna
} /~LXY<-(
ecH-JPm'
hCLXL
QxGQF|
p]zYj >e
至此,一个完整的分页程序完成。前台的只需要调用 i~IQlyGr.
B9Dh^9?L
userManager.listUser(page)即可得到一个Page对象和结果集对象 Qw$"W/&X
W].P(A>m
的综合体,而传入的参数page对象则可以由前台传入,如果用 ,Dz2cR6
x,Cc$C~YP
webwork,甚至可以直接在配置文件中指定。 l}DCK
IKK<D'6
下面给出一个webwork调用示例: K+` Vn
java代码: :);]E-ch
#&1Y!kbdd
LaE;{ jY
/*Created on 2005-6-17*/ %}=$HwN)
package com.adt.action.user; I~R<}volu
wjmZ`UMz
import java.util.List; {1GW,T!#
%;0w2W
import org.apache.commons.logging.Log; fxDY:l
import org.apache.commons.logging.LogFactory; hG,gY;&[6
import org.flyware.util.page.Page; 2.2Z'$W
xrT_ro8
import com.adt.bo.Result; r<oI4px
import com.adt.service.UserService; 6bg+U`&g
import com.opensymphony.xwork.Action; n;"4`6L~
/S;o2\
/** xaerMr
* @author Joa a{h(BI^~
*/ #^Dc:1,
publicclass ListUser implementsAction{ SPV'0* Z
j8os6I
privatestaticfinal Log logger = LogFactory.getLog 3D~Fu8Hg1
'3o0J\cz
(ListUser.class); 5Ag>,>kJ6
Xl6)&
private UserService userService; Q:~w;I
D^PsV
private Page page; [&*$!M
Et'C4od s
privateList users; wN)R !6
bE>3D#V<
/* ABV\:u
* (non-Javadoc) ,l<-*yMD
* z1+rz%
* @see com.opensymphony.xwork.Action#execute() 1#qCD["8
*/ LM'` U-/e$
publicString execute()throwsException{ +29;T0>a
Result result = userService.listUser(page); T , =ga
page = result.getPage(); t%z7#}9$
users = result.getContent(); IQ{Xj3;?y
return SUCCESS; V8&/O)} o
} L1Q QU
]@J}f}Mjo
/** (?\ZN+V)
* @return Returns the page. !BEOeq@2.
*/ U>;itHW/
public Page getPage(){ ?<frU ,{
return page; T *t$
} -R'p^cMA
7IJb$af:;
/** ~v>w%]
* @return Returns the users. YY!(/<VI
*/ \ b9,>
publicList getUsers(){ na']{a1K
return users; ;(0:6P8I
} `A
<yDy
UxicqkX
/** 24N,Bo
3
* @param page Dlj=$25
* The page to set. N/?MsrZw
*/ HHnabSn}{q
publicvoid setPage(Page page){ MF\n@lX
this.page = page; ,.`^Wx6F
} 6 qKIz{;
!v;r3*#Nky
/** UuT[UB=x5
* @param users )N=b<%WD
* The users to set. /1li^</|p`
*/ G0s:Dum
publicvoid setUsers(List users){ A}y1v;FB
this.users = users; c0G/irK
} deTbvl
RO.(k!J .
/** vWkKNB
* @param userService "(efd~.]
* The userService to set. b"FsT
*/ yL
Q&<\
publicvoid setUserService(UserService userService){ pO+1?c43
this.userService = userService; c?R.SBr,'
} _TPo=}Z
} jATU b-
H4:TYh
6$6NVq
ESrWRO
f9
X3m?zQbhv
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, *Ra")(RnDK
fA,+qs
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 5N/]/
j=AJs<
么只需要: oNU* q.Q
java代码: ONGe/CEXT
mW-@-5Wda
I(<G;ft<}
<?xml version="1.0"?> qBNiuV;*
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork `X^e}EGWu
YqJIp. Z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- /MU<)[*Ro
<@vE3v;
1.0.dtd"> `2fuV]FW
E7h}0DX
<xwork> wKeqR$
yY| .
<package name="user" extends="webwork- 3QHZC0AY
{PVu3W
interceptors"> ]czy8n$+
)[K3p{4
<!-- The default interceptor stack name ibuI/VDF
|"-,C}O
--> ~Op1NE
<default-interceptor-ref rka:.#!
2DC#PX)i
name="myDefaultWebStack"/> 3
#wj-
;p_X7N
<action name="listUser" !xc7~D@om(
y^A$bTQq
class="com.adt.action.user.ListUser"> QLUe{@ivc
<param $($SQZK&
~/x42|t
name="page.everyPage">10</param> P&tK}Se^V
<result )g --=w3
aOD"z7}U
name="success">/user/user_list.jsp</result> Ax^'unfQ:
</action> Ji!-G4.n"
^"l$p,P+
</package> Qm.kXlsDI
0\#Q;Z2
</xwork> % *G)*n
lewDR"0Kx
'AAY!{>
fA8+SaXW%
Fq9[:
9vbh5xX
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 7xc<vl#:q7
3PA'Uk"5Z
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 >" .qFn g
m%V[&"5%e
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 :z\f.+MI
CN=&Je%I
}m H>lN
Vw*x3>`
Ax0,7,8y
我写的一个用于分页的类,用了泛型了,hoho +Y~+o-_
W =zG
java代码: g=C<E2'i*
|u{QI3#'
=eqI]rVj^
package com.intokr.util; g,:Nzb
C P#79=1
import java.util.List; eC$v0Gtq
F&*M$@u5
/** &FrB6y
* 用于分页的类<br> 9^ r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> C'._}\nX
* iW?9oe
* @version 0.01 YP<]f>SBt
* @author cheng ~qS/90,
*/ !T*B{+|
public class Paginator<E> { <yS"c5D6
privateint count = 0; // 总记录数 hQm4R]a
privateint p = 1; // 页编号 m=MT`-:
privateint num = 20; // 每页的记录数 BB.TrQM.#
privateList<E> results = null; // 结果 a+/|O*>#
>y9o&D