Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ciHTnC
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 O> wGJ.
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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 ) \cnz
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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 y(Pv1=e
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分页支持类: ~8Ef`zL
@$ )C pg
java代码: wGz_IL.D
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package com.javaeye.common.util; '~6l
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import java.util.List; ^3&-!<*
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publicclass PaginationSupport { .}tpEvAw}
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publicfinalstaticint PAGESIZE = 30; ijNI6_eU
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privateint pageSize = PAGESIZE; H~<wAer,Op
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privateList items; '(:R-u!pp
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privateint totalCount; l~`JFWur]
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privateint[] indexes = newint[0]; /3`fO^39Ta
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privateint startIndex = 0; xiQd[[(sM
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public PaginationSupport(List items, int kb*b|pWlO
=?B[oq
totalCount){ vinn|_s%
setPageSize(PAGESIZE); L!W5H2Mc
setTotalCount(totalCount); 'Ya- ;5Y]
setItems(items); x A ZRl
setStartIndex(0); 28,HZaXhc
} 5sMyH[5zY
kL}*,8s{
public PaginationSupport(List items, int "k7C
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totalCount, int startIndex){ Bv=:F5hLG
setPageSize(PAGESIZE); *5'l"YQ@1
setTotalCount(totalCount); Su`]
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setItems(items); Fc"+L+h@W
setStartIndex(startIndex); cT^x^%
} t4,(W`
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public PaginationSupport(List items, int ^t)alNGos
O$&4{h`
totalCount, int pageSize, int startIndex){ CY.i0
setPageSize(pageSize); v/C*?/ ~
setTotalCount(totalCount); ^$\#aTyFK
setItems(items); {[FJkP2l
setStartIndex(startIndex); Hh;o<N>U
} R 9Yk9v
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publicList getItems(){ \E:l
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return items; 2W`<P2IA
} {&Sr<d5
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publicvoid setItems(List items){ \M-$|04Qt
this.items = items; LfS]m>>e
} =Cr
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wo!;Bxo
N
publicint getPageSize(){ ehYGw2
return pageSize; Q\v^3u2;m`
} k'Z$#
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publicvoid setPageSize(int pageSize){ q0]Z` <w
this.pageSize = pageSize; *6*/kV?F
} p[gq^5WuC
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publicint getTotalCount(){ e;)&Hc:Z
return totalCount; ,n+~S^r
} E@$HO_;&
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publicvoid setTotalCount(int totalCount){ #kDJ>r |&-
if(totalCount > 0){ ~Aq$GH4
this.totalCount = totalCount; %L;'C
v
int count = totalCount / <q#/z&F!
?f[U8S}
pageSize; nHi6$}
I
if(totalCount % pageSize > 0) Ej64^*
count++; H;eOrX{GT
indexes = newint[count]; f0lK,U@P
for(int i = 0; i < count; i++){ z}m)u
indexes = pageSize * xu0pY(n^r
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i; j*)K>
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} zd3%9r j$
}else{ {VrjDj+Xy
this.totalCount = 0; <swYo<?J#
} [6t!}q
} #EdsB
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publicint[] getIndexes(){ !NFP=m1
return indexes; 4
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} 0?nm`9v6
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publicvoid setIndexes(int[] indexes){ Kzd)Z
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this.indexes = indexes; JmK[7t
} BPzlt
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publicint getStartIndex(){ 14v,z;HXj
return startIndex;
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} YV0K&d
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publicvoid setStartIndex(int startIndex){ BWN[>H %S
if(totalCount <= 0) S7
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this.startIndex = 0; 2r=A'
elseif(startIndex >= totalCount) FO5'<G-
this.startIndex = indexes !EQMTF=(
v(tr:[V
[indexes.length - 1]; h
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elseif(startIndex < 0) 7&z`N^dz{
this.startIndex = 0; "ewB4F[
else{ 9>"To
this.startIndex = indexes kdrya
M%8:
[startIndex / pageSize]; 5#U*vGVT
} UF00K1dbz
} ,HQaS9vBQ
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publicint getNextIndex(){ aBLE:v
int nextIndex = getStartIndex() + qrmJJSJ
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pageSize; `o~9a N
if(nextIndex >= totalCount) M6b;
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return getStartIndex(); isP4*g&%x
else IuQY~!
return nextIndex; t~0}Emgp<(
} jreY'y:
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publicint getPreviousIndex(){ ~\z\f}w
int previousIndex = getStartIndex() - OW12m{
wb
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pageSize; v5 yOh5
if(previousIndex < 0) ?N|B, F
return0; YrR}55V,
else 3' WS6B+
return previousIndex; e_BOzN~c
} X192Lar
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} v?7.)2XcX
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抽象业务类 VlVd"jW
java代码: WJ+<&6W8
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/** 2EOt.4cP
* Created on 2005-7-12 ;TK:D=p4
*/ ,zLi{a6
package com.javaeye.common.business; <o_H]c->
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import java.io.Serializable; m3k}Q3&6Z
import java.util.List; v|XEC[F
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import org.hibernate.Criteria; TWC^M{e
import org.hibernate.HibernateException; ^zv28Wq>
import org.hibernate.Session; TCSm#?[B
import org.hibernate.criterion.DetachedCriteria; u=I>DEe@c
import org.hibernate.criterion.Projections; or u.a
import ) tGC&l+?/
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org.springframework.orm.hibernate3.HibernateCallback; SLc6]?
import J0}OmNTzD
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org.springframework.orm.hibernate3.support.HibernateDaoS R0M(e@H~
kg$<^:uX
upport; Zjt3U;Y
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import com.javaeye.common.util.PaginationSupport; 7:1c5F~M
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public abstract class AbstractManager extends e/WR\B'1
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HibernateDaoSupport { Rp)82-
.
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privateboolean cacheQueries = false; 4b8!LzKS
4
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privateString queryCacheRegion; E#_TX3B
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publicvoid setCacheQueries(boolean h]<Ld9
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cacheQueries){ "6n~,$
this.cacheQueries = cacheQueries; n-dO |3,
} //W<\
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publicvoid setQueryCacheRegion(String ;""V s6
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queryCacheRegion){ 2Ni$
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this.queryCacheRegion = 4ow)vS(
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queryCacheRegion; +"a .,-f!
} ~)}npS;
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publicvoid save(finalObject entity){ j]6j!.1
getHibernateTemplate().save(entity); ocy fU=}X
} ~l-Q0wg
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publicvoid persist(finalObject entity){ Hq^sU%
getHibernateTemplate().save(entity); gQ*0Mk
} r9G<HKl
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publicvoid update(finalObject entity){ a[)in ,3
getHibernateTemplate().update(entity);
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} dKw*L|5
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publicvoid delete(finalObject entity){ 4)iSz>
getHibernateTemplate().delete(entity); bzmT.!
} HW{osav9
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publicObject load(finalClass entity, 7,_N9Q]rB
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finalSerializable id){ {y'c*NS
return getHibernateTemplate().load 8|?$KLz?F>
@q2Yka
(entity, id); V$-IRdb
} &M~*w~w`
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publicObject get(finalClass entity, Y,B0=}
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finalSerializable id){ R1X9
return getHibernateTemplate().get *:3flJt
y-{^L`%Mk
(entity, id); GLt#]I"LY
} ooByGQ90V:
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publicList findAll(finalClass entity){ Ym-uElWo
return getHibernateTemplate().find("from <r,l
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" + entity.getName()); KQ xKU?b1
} 1,Uv;s;{
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publicList findByNamedQuery(finalString xe|o(!(
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namedQuery){ A--Hg-N|
return getHibernateTemplate J(h=@cw
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().findByNamedQuery(namedQuery); v-X1if1%
} 4)-LlYS_d<
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publicList findByNamedQuery(finalString query, 5Y"lr Y38
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finalObject parameter){ &2MW.,e7s
return getHibernateTemplate @P4fR7
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().findByNamedQuery(query, parameter); :p(3Ap2TY
} _UYt
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publicList findByNamedQuery(finalString query, "o`N6@[w^
@X"p"3V
finalObject[] parameters){ a84^"GH7
return getHibernateTemplate l[l('-f
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().findByNamedQuery(query, parameters); ]0zXpMNI
} ?z171X0
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publicList find(finalString query){ U"A]b(54
return getHibernateTemplate().find 2r"-X
//\ORJd
(query); (+38z)f
} v1QE|@
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publicList find(finalString query, finalObject I7nt<l!
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parameter){ *;(LKRV
return getHibernateTemplate().find B[!wo
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(query, parameter); @/ wJW``;
} ( N~[sf?&
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria){ $xyG0Q.
return findPageByCriteria lKrD.iYt8
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "?EA G
} ]YQlCx`
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public PaginationSupport findPageByCriteria i))S%!/r~
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(final DetachedCriteria detachedCriteria, finalint f[HhLAVGK`
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startIndex){ <bWhTNOb
return findPageByCriteria Q_euNoA0
m\__Fl
(detachedCriteria, PaginationSupport.PAGESIZE, ZTWbe
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startIndex); *
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} } '. l'%
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public PaginationSupport findPageByCriteria 4$+1jjC]>~
8=FP92X
(final DetachedCriteria detachedCriteria, finalint p-GlGEt_X
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pageSize, >;dMumX
finalint startIndex){ { ,/mQ3
return(PaginationSupport) !iWPldn&]
j#"?Oe{_1
getHibernateTemplate().execute(new HibernateCallback(){ t(-noy)
publicObject doInHibernate KtU I(*$`
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(Session session)throws HibernateException { p)N=
Criteria criteria = 8xs[{?|:
.vj`[?T
detachedCriteria.getExecutableCriteria(session); S
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int totalCount = p[VBeO^%
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((Integer) criteria.setProjection(Projections.rowCount ` =RJ8u
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()).uniqueResult()).intValue(); I#zrz3WU
criteria.setProjection %kS +n_*
IExo#\0'6
(null); SEq_37
List items = :D8V*F6P
`@b+'L
criteria.setFirstResult(startIndex).setMaxResults ,OsFv}v7
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(pageSize).list(); ^]3Y11sI
PaginationSupport ps = rP>iPDf
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new PaginationSupport(items, totalCount, pageSize, //nR=Dy{
v}!eJzeH
startIndex); >t&Frw/Bl
return ps; 8 sZ~3
} hn#i,XnY
}, true); ya0L8`q
} Mp^%.m
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public List findAllByCriteria(final @tWyc%t
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DetachedCriteria detachedCriteria){ bYGK}:T8U
return(List) getHibernateTemplate rn #FmM
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().execute(new HibernateCallback(){ 9}Ud'#E
publicObject doInHibernate uV!Ax*'
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(Session session)throws HibernateException { {O9CYP:
Criteria criteria = [x
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detachedCriteria.getExecutableCriteria(session); wN\%b}pp
return criteria.list(); ?2zVWZ
} /_5I}{
}, true); @,F8gv*
} Fq>=0 )
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public int getCountByCriteria(final 47.c
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DetachedCriteria detachedCriteria){ ,)e&u1'
Integer count = (Integer) &Ed7|k]H
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getHibernateTemplate().execute(new HibernateCallback(){ Kq
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publicObject doInHibernate r!N)pt<g
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(Session session)throws HibernateException { o^hI\9
Criteria criteria =
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detachedCriteria.getExecutableCriteria(session); {"$
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return y! he<4
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criteria.setProjection(Projections.rowCount P,r9<
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()).uniqueResult(); aG.j0`)%
} 7p%W)=v
}, true); qq"&Bc>
return count.intValue(); 9?a-1
} dznHR6x
} -Zx
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用户在web层构造查询条件detachedCriteria,和可选的 9v>BP`Mg
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 eYZ{mo7
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PaginationSupport的实例ps。 /cHd&i,>
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ps.getItems()得到已分页好的结果集 bh9rsRb}O
ps.getIndexes()得到分页索引的数组 ],CJSA!5F
ps.getTotalCount()得到总结果数 iJ.P&T9
ps.getStartIndex()当前分页索引 Ylbh_ d~BU
ps.getNextIndex()下一页索引 V\Oe ]w
ps.getPreviousIndex()上一页索引 ^%l~|w
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 q>:>f+4
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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 ;AyE(|U+
W/_=S+CvK
一下代码重构了。 G{$(t\>8
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我把原本我的做法也提供出来供大家讨论吧: x xxM
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首先,为了实现分页查询,我封装了一个Page类: 3Mw\}q
java代码: :N03$Tvl
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/*Created on 2005-4-14*/ ngF5ywIG
package org.flyware.util.page; RDU,yTHq
O%? TxzX;
/** .Rt_j
* @author Joa !u~h.DrvZ
* G8xM]'y
*/ sVP[7&vr~
publicclass Page { ?^]29p_
&atT7m
/** imply if the page has previous page */ PZ5BtDm
privateboolean hasPrePage; 7tWt3
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/** imply if the page has next page */ )zw}+z3st
privateboolean hasNextPage; B.w ihJVDg
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/** the number of every page */ }p-<+sFo
privateint everyPage; mXZOkx{
C =fs[
/** the total page number */ Y4*ezt:;Q
privateint totalPage; +g36,!q
'Okitq+O
/** the number of current page */ ! K? o H
privateint currentPage; bz!9\D|h
hKq <e%oVH
/** the begin index of the records by the current vqh@)B+)
r~q*E'n
query */ +zodkB~)
privateint beginIndex; s@C KZ`
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+N0V8T%~z.
/** The default constructor */ g1U
public Page(){ Gy{C*m7Q
}'HJV B_
} :%GxU;<E{
.#n1p:}[
/** construct the page by everyPage 5G.A\`u%
* @param everyPage ?^iX%
* */ z9mmZqhK\
public Page(int everyPage){ gs;3NW
this.everyPage = everyPage; z_fR?~$N2
} RFF&-M]
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/** The whole constructor */ C6Qnn@waYb
public Page(boolean hasPrePage, boolean hasNextPage, \ZdV|23
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9( ;lcOz
int everyPage, int totalPage, u@d`$]/>F
int currentPage, int beginIndex){ Hbogi1!al|
this.hasPrePage = hasPrePage; X\3IY:Q@T
this.hasNextPage = hasNextPage; _Y@'<S.
this.everyPage = everyPage; PAF2=
this.totalPage = totalPage; 1_vaSEov
this.currentPage = currentPage; KobNi#O+
this.beginIndex = beginIndex; R03V+t=
} TbyQ'MbUv
5=CLR
/** nA8]/r1k
* @return YpQ/ )fSEV
* Returns the beginIndex. zjd]65P
*/ dtJaQ`
publicint getBeginIndex(){ +gb2>fei&
return beginIndex; l'YpSO~l7
} 9k.LV/Y
Ko% &~C_
/** T
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* @param beginIndex ]X4
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* The beginIndex to set. b6=.6?H@4f
*/ k#k !AcC
publicvoid setBeginIndex(int beginIndex){ 42:~oKiQ$"
this.beginIndex = beginIndex; k,0RpE
} (bH*i\W
N*JWd
/** WE$Pi;q1
* @return w?kdM1T
* Returns the currentPage. Zcd!y9]#
*/ +) 2c\1
publicint getCurrentPage(){ TL@_m^SM
return currentPage; GIQ/gM?Pv
} ji{V#
d|Wpub
/** j6Acd~y\2
* @param currentPage Eugt~j3
* The currentPage to set. \2i4]V
*/ jTk !wm=
publicvoid setCurrentPage(int currentPage){ *%5#\ I
this.currentPage = currentPage; 3$+|nP:U
} ~V3pj('/)'
Y}(#kqh>
/** ]5D?Sc#-
* @return DV +DJcF
* Returns the everyPage. 8YFfnk
*/ u#XNl":x
publicint getEveryPage(){ Vea>T^
return everyPage; !pl<
} *{:FPmDU
xin<.)!E
/** (A`/3Aq+
* @param everyPage M$A"<5
* The everyPage to set. 1fwCQM
*/ 7dI+aJ
publicvoid setEveryPage(int everyPage){ Sj{z
this.everyPage = everyPage; ;<0Q<0G
} bnLvJ]i)
5T}$+R0&
/** hX\XNiCiK8
* @return dUeM+(s1
* Returns the hasNextPage. Y1EN|!WZ
*/ AR'q2/cw
publicboolean getHasNextPage(){ [La=z7*
return hasNextPage; +jzpB*@
} \Oh9)X:I
0rY<CV;fZ
/** 9ZUG~d7_
* @param hasNextPage JE,R[` &
* The hasNextPage to set. E,E:W uB
*/ :
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publicvoid setHasNextPage(boolean hasNextPage){ Hx2.2A^
this.hasNextPage = hasNextPage; u$x HiD
} P:t|'t
_={*<E
/** ^dH#n~Wx0
* @return a_'W1ek-@
* Returns the hasPrePage. x- ) D@dw<
*/ \^SL Zhe
publicboolean getHasPrePage(){ a^i`DrX
return hasPrePage; yyxGVfr
} -wlob`3
=UA-&x@
/** \tLJ( <8
* @param hasPrePage /ow/)\/}
* The hasPrePage to set. ?rXh
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*/ T=:&W3
publicvoid setHasPrePage(boolean hasPrePage){ =K{$?%"
this.hasPrePage = hasPrePage; Q?n} ~(%&
} j,eeQ KH
"t~I;%$[
/** h>$,97EU
* @return Returns the totalPage.
' ^gF
* hFuS>Hx
*/ ov zIJbf
publicint getTotalPage(){ :^lyVQ%@
return totalPage; O:Bfbna
} b,/fz6
{N
^"K
/** yAR''>
* @param totalPage 0}hN/2}&
* The totalPage to set. fm87?RgXD
*/ ?/)Mt(p
publicvoid setTotalPage(int totalPage){ :h0as!2@dp
this.totalPage = totalPage; v>.nL(VLjP
} cEi{+rfZd|
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} V=k!&xN~
ui`xgR\6Rh
=1)yI>2e%}
3SVI|A5(d
O\pqZ`E=s
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 au}rS0)+
oP5G*AFUq
个PageUtil,负责对Page对象进行构造: >>Hsx2M
java代码: #*,Jqr2f
I>bLgt]u3
Pk[f_%0
/*Created on 2005-4-14*/ C\dQ6(3}\
package org.flyware.util.page; jJ?MT#v
FyJI@PZdI-
import org.apache.commons.logging.Log; Mkko1T=6
import org.apache.commons.logging.LogFactory; $iDatQ[
2:MB u5**
/** 3X*;.'#Z
* @author Joa f(
hK>H
* fo&q/;l\
*/ !0c7nzjm
publicclass PageUtil { .\X/o!xC
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privatestaticfinal Log logger = LogFactory.getLog 6(B0gBCId
9c9-1iS
(PageUtil.class); Q#urx^aw
JM -Tp!C>
/** @5\OM#WT~&
* Use the origin page to create a new page >k*QkIyq
* @param page u!oHP
* @param totalRecords M:6H%6eT
* @return "w=p@/C
*/ DUEA"m h
publicstatic Page createPage(Page page, int U# Y?'3 :
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totalRecords){ 8|{:N>7
return createPage(page.getEveryPage(), wJ1qJ!s@
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page.getCurrentPage(), totalRecords); /#20`;~F)
} 5|NM]8^^0[
l Vo](#W
/** ]o$Kh$~5
* the basic page utils not including exception 5dT-{c%w4
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handler idvEE6I@
* @param everyPage UB&ofO
* @param currentPage b.47KJz t
* @param totalRecords y&t&'l/m
* @return page fC.-* r
*/ 4o9#B:N]J
publicstatic Page createPage(int everyPage, int hz<kR@k}
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currentPage, int totalRecords){ WTA0S}pT
everyPage = getEveryPage(everyPage); ml.l( 6A
currentPage = getCurrentPage(currentPage); iBwl(,)?m2
int beginIndex = getBeginIndex(everyPage, l6Ze6X I
?JzLn,&
currentPage); x%k4Lm
int totalPage = getTotalPage(everyPage, Ig"Krz
5oGnPF
totalRecords); 63UAN0K%
boolean hasNextPage = hasNextPage(currentPage, @]6)j&
zOLt)2-<
totalPage); '|':W6m,
boolean hasPrePage = hasPrePage(currentPage); YTL [z:k}
I"#jSazk
returnnew Page(hasPrePage, hasNextPage, [X#bDO<t
everyPage, totalPage, =+T{!+|6P
currentPage, -9} ]J\
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beginIndex); 8? W\kf$
} (03m%\
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privatestaticint getEveryPage(int everyPage){ !ceuljd]
return everyPage == 0 ? 10 : everyPage; LDBxw
} }di)4=U9
v[e$RH
privatestaticint getCurrentPage(int currentPage){ j,/OzVm9
return currentPage == 0 ? 1 : currentPage; 7`6n]4e
} J^hj
R%H
S-gL]r3G8
privatestaticint getBeginIndex(int everyPage, int vpvPRwJ
aN).G1
currentPage){ L;Nz\sJ
return(currentPage - 1) * everyPage; #?}k0Y
} 9x ?" %b
-x_b^)x~b7
privatestaticint getTotalPage(int everyPage, int RSG4A>%!mI
g (ZeGNV8
totalRecords){ =4\|'V15
int totalPage = 0; K*'(;1AiW
2[[pd&MJZ
if(totalRecords % everyPage == 0) c;Hf +n
totalPage = totalRecords / everyPage; mc?5,oz;pz
else A~\:}PN
totalPage = totalRecords / everyPage + 1 ; tB &D~M6[
BEg%u)"([
return totalPage; P}~6yX
} qdCa]n!d
Rde#=>@V
privatestaticboolean hasPrePage(int currentPage){ IxYuJpi
return currentPage == 1 ? false : true; 0+P_z(93?
} {K*l,U
,'= Y
privatestaticboolean hasNextPage(int currentPage, sw' 20I
R/~j <.s3P
int totalPage){ 9TO
return currentPage == totalPage || totalPage == 2Q|Vg*x\U
3VCyq7B^
0 ? false : true; x7L$x=8s
} YMIDV-
_;yp^^S
~uq J@#o{
} 7{D+\i
o83HR[
i'L7t!f}o
M)Yu^
x(hUQu 6
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。 Wgq*| teW
"}\z7^.W>
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]/ c
pA!+;Y!ZB<
做法如下: |5F]y"Nb
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 []1VD#
rD%(*|Y"c
的信息,和一个结果集List: CP7Zin1S/w
java代码: AXH4jQw
]QtdT8~
5[al^'y
/*Created on 2005-6-13*/ x|U]x
package com.adt.bo; )KaQ\WJ:
Zu$f-_"
import java.util.List; /!eC;qp;[
{3$ge
import org.flyware.util.page.Page; }qmZ
?)",}XL6
/** R{8nR00|1
* @author Joa 3`n5[RV
*/ e&8pTD3
publicclass Result { }Da8S|)H
9gn_\!Mp
private Page page; CYEqH2"3
YXg:cXE8e
private List content; aPcO9
$$A{|4,aI
/** y`mE sj
* The default constructor *.Y!ZaK
*/ @xtcjB9
public Result(){ L
G,XhN
super(); =Q.2:*d.
} gEO#-tMjOQ
l#~Sh3@L(
/** {u9(qd;;
* The constructor using fields fF_1ZKx+#!
* kkyn>Wxv
* @param page V*5:Vt7N
* @param content RT)0I;
*/ WQv~<]1JF
public Result(Page page, List content){ @-kzSm
this.page = page;
iq5h[
this.content = content; +m:U9K(\h
} !b rN)b)f
k1$|vzMh
/** <Sm=,Sw
* @return Returns the content. =(Mv@eA"
*/ ~)tMR9=wX
publicList getContent(){ OrPIvP<w@
return content; u`gy1t `
} mXz-#Go(
WT'P[RU2
/** lLmVat(
* @return Returns the page. ? RB~%^c!
*/ ]B3 0d
public Page getPage(){ 5}*aP
return page; D4Uz@2_
} ]o6yU#zn~e
lr +Kwve
/** +@Fy) {C7
* @param content OZ![9l
* The content to set. mrqCW]#u
*/ &KbtW_
public void setContent(List content){ d+fmVM?p
this.content = content; 70lb6A
} -66|Y
"LaNXZ9
/** z.e%AcX
* @param page 1
YMaUyL
1
* The page to set. &^ =t%A%#
*/ Hi,_qlc+
publicvoid setPage(Page page){ D<L]'
this.page = page; T"kaOy
} mRj-$:}L
} rU<
H7U
x:xKlPGd
nP 2 rN_:4
eff6=DP
s3g$F23
2. 编写业务逻辑接口,并实现它(UserManager, M`BD]{tN}
Eqp?cKrji
UserManagerImpl) u$t*jw\fHg
java代码: LP@Q8{'
f@\
k_
v{Zh!mk* L
/*Created on 2005-7-15*/ w,eYrxR|N
package com.adt.service; [ueT]%
%CF(SK2w
import net.sf.hibernate.HibernateException; -T4?5T_
:/~`"`#1
import org.flyware.util.page.Page; Haj`mc!<D0
.g(yTA
import com.adt.bo.Result; e<~uU9
lg1
FxM`$n~K
/** HY5g>wv@
* @author Joa [Gh T.
*/ kul&m|
publicinterface UserManager { ~;UK/OZ
lCWk)m8
public Result listUser(Page page)throws w gATfygr
+wD--24!(
HibernateException; hrU.QF8
;fee<7Ty
} J:#B,2F+^
oF]0o`U&a
E`LML?
Fd5{ pM3
vq( @B
java代码: K`(STvtM
d!G%n
*
{n$9o
/*Created on 2005-7-15*/ egx(N
<
package com.adt.service.impl; e_k1pox]l
E^A9u
|x
import java.util.List; +c}fDrr)
;OPz T9
import net.sf.hibernate.HibernateException; {-Yp~HQF
GG(rp]rgl
import org.flyware.util.page.Page; HxU.kcf
import org.flyware.util.page.PageUtil; q6H90Zb
!rTh+F*
import com.adt.bo.Result; aWOApXJ
import com.adt.dao.UserDAO; ^YenS6`F
import com.adt.exception.ObjectNotFoundException; ~`T(mh',
import com.adt.service.UserManager; j\@s pbE@
iknB c-TLD
/** 9Hlu%R
* @author Joa hd/5*C{s
*/ 9p2"5x
publicclass UserManagerImpl implements UserManager { &IXr*I
hkHMBsNi
private UserDAO userDAO; ,6i67!lb
c{|soc[#
/** ?
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* @param userDAO The userDAO to set. C*kZ>mbc
*/ -Zocu<Rs
publicvoid setUserDAO(UserDAO userDAO){ VIAj]Ul
this.userDAO = userDAO; (zk'i13#6
} Sh2q#7hf
>,uof ?
/* (non-Javadoc) Xw9,O8}C7
* @see com.adt.service.UserManager#listUser *bmk(%g
A){kitx-i)
(org.flyware.util.page.Page) I0m/
*/ KM< M^l_Q
public Result listUser(Page page)throws '(^p$=3|@D
#mx;t3ja7
HibernateException, ObjectNotFoundException { RL.%o?<&?
int totalRecords = userDAO.getUserCount(); +Nc|cj
if(totalRecords == 0) ?P{C=Td2z
throw new ObjectNotFoundException s8@f Z4
Be8Gx
("userNotExist"); t8]u#bx"?
page = PageUtil.createPage(page, totalRecords); oo-^BG
List users = userDAO.getUserByPage(page); cO)GiWE
returnnew Result(page, users); YDs/BF
Z
} "Q2[A]4E
6$fC
R
} <adu^5BI
.?!{. D
0<!kGL5
99:`58G
-uy}]s5Qu
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 I>L
lc Y
jqb,^T|j;m
询,接下来编写UserDAO的代码: \
{"8(ELX
3. UserDAO 和 UserDAOImpl: kJJQcjAP:
java代码: W=I%3F_C"R
ScZ$&n
;u}MG3Y8
/*Created on 2005-7-15*/ oJyC{G
package com.adt.dao; I`Rxijz
)bPNL$O
import java.util.List; PeTA:MW
6Oo'&3@
import org.flyware.util.page.Page; ^h^j:!76j
+n2x@ 0op
import net.sf.hibernate.HibernateException; t
m5>J)C
9L!Vj J
/** 4.H!rkMM
* @author Joa <XCH{Te1
*/ 47$JN}qI0
publicinterface UserDAO extends BaseDAO { >s[}f6*2@
Z# 7HuAF{]
publicList getUserByName(String name)throws +1h^9Y'
>a_K:O|AJ
HibernateException; 1;ZEuO
?G!^|^S*
publicint getUserCount()throws HibernateException; nez5z:7F
z0g$+bhy
publicList getUserByPage(Page page)throws bgYM
^Ud`2 OW;2
HibernateException; tet
t M A
} ,,fLK1
ELY$ ]^T
JK,#dA#
,ZMYCl]
yU .B(|
java代码: r'xa'6&
-#rFCfPy^
f4@Dn
>BJ
/*Created on 2005-7-15*/ {a%T <WW
package com.adt.dao.impl; BtU,1`El5
El"XF?OgpP
import java.util.List; DU}q4u@)
M7jDV|Go
import org.flyware.util.page.Page; R8":1 #&
mN@0lfk;
import net.sf.hibernate.HibernateException; :*}tkr4&eh
import net.sf.hibernate.Query; V :d/;~
hDmVv;M:
import com.adt.dao.UserDAO; AbcLHV.
bs_I{bCu?
/** _ogT(uYyr
* @author Joa 60X B
*/ ^+,mxV'8!
public class UserDAOImpl extends BaseDAOHibernateImpl #i)h0ML/e
:,GsbNKW
implements UserDAO { 5
0~L(<
s2w.V
O
/* (non-Javadoc) '|WMt g
* @see com.adt.dao.UserDAO#getUserByName #-e3m/>
8&`s wu&
(java.lang.String) j}0*`[c
*/ xwK<f6H!y
publicList getUserByName(String name)throws XPWK"t01
27,WP-qie
HibernateException { _NqEhf:8
String querySentence = "FROM user in class ^f3F~XhY3
\>,{)j q;
com.adt.po.User WHERE user.name=:name"; RJBNY;0
Query query = getSession().createQuery oleRQ=
n:k~\-&WJ
(querySentence); W P.6ea7k
query.setParameter("name", name); &a48DCZ
return query.list(); <([o4%
} *h-nI=
#C!8a
/* (non-Javadoc) <M+ZlF-`
* @see com.adt.dao.UserDAO#getUserCount() 2psLX
*/ NUx%zY
publicint getUserCount()throws HibernateException { ,Sz*]X
int count = 0; WOgbz&S?J
String querySentence = "SELECT count(*) FROM 9LCV"xgX
N],A&}30
user in class com.adt.po.User"; O \lt!p3F
Query query = getSession().createQuery K mL
PWj
5^P)='0*
(querySentence); w6#hsRq[C
count = ((Integer)query.iterate().next hnG'L*HooE
*W#x#0j
()).intValue(); 9>%f99n
return count; PlBT
H
} ^5"s3Qn
\7("bB=
/* (non-Javadoc) t^u X9yvx
* @see com.adt.dao.UserDAO#getUserByPage {\lu; b!
h'kgL~+$
(org.flyware.util.page.Page) F=d#$-yg
*/ +s_@964
publicList getUserByPage(Page page)throws ^*}L9Ot~
*qKwu?]?>
HibernateException { Eiz\Nb
String querySentence = "FROM user in class W%~ S~wx
y;#p=,r
com.adt.po.User"; wf8vKl#Kfw
Query query = getSession().createQuery $Ce`(/
m<"1*d~
(querySentence); w*Kw#m'U
query.setFirstResult(page.getBeginIndex()) 8(uxz84ce
.setMaxResults(page.getEveryPage()); f9OVylm
return query.list(); {WFYNEQ[
} =X-$kk
Zf(ucAhL
} %2/WyD$U
> -k$:[l
O^sgUT1O
)"j_NlO
?^,GaZ^V
至此,一个完整的分页程序完成。前台的只需要调用 LH<--#K
Cn+TcdHX
userManager.listUser(page)即可得到一个Page对象和结果集对象 c;(}Ih(#
;k!Ej-(
的综合体,而传入的参数page对象则可以由前台传入,如果用 rQ~%SUM7
^#gGA_H
webwork,甚至可以直接在配置文件中指定。 \n+`~< i
B>9D@fmzs
下面给出一个webwork调用示例: bjD0y
cB[
java代码: FC vR
H(n_g
QAX
7J0PO}N
/*Created on 2005-6-17*/ (K0FWTmm
package com.adt.action.user; KOwEw~
lc[\S4
import java.util.List; QN*'MA"M
tJ'U<s
import org.apache.commons.logging.Log; .@ 1\26<
import org.apache.commons.logging.LogFactory; )c+ZQq
import org.flyware.util.page.Page; c$1ez
~EX/IIa{
import com.adt.bo.Result; B4U+q|OD#
import com.adt.service.UserService; 5r`g6@
import com.opensymphony.xwork.Action; ! =|{
Udd|. J Rd
/** Z\LW<**b
* @author Joa (QqKttL:
*/ =BNmuAY7
publicclass ListUser implementsAction{ =]etw
J#'c+\B<2X
privatestaticfinal Log logger = LogFactory.getLog CUY2eQJ{U
%Ix^Xb0
(ListUser.class); 2/(gf[elX
Xj|j\2$ 0
private UserService userService; ;QW)tv.y
DAc jx:~
private Page page; /z5j.TMs
qRB&R$
privateList users; Wp T.25
`[Z?&'CRQ
/* oh,Nu_!
* (non-Javadoc) IsnC_"f
* S@T>u,t'
* @see com.opensymphony.xwork.Action#execute() +gK7`:v4O*
*/ dHd{9ftyF
publicString execute()throwsException{ B#sc!eLmU&
Result result = userService.listUser(page); qmJFXnf
page = result.getPage(); u3"F7
lJ
users = result.getContent(); X8?|5$Ey
return SUCCESS; 4sROMk=l
} [+ 1([#
0'aZ*ozk
/** S(/@.gI:f
* @return Returns the page. [(UQQa=+
*/ uw;s](~E
public Page getPage(){ 8 rnr>Ee@
return page; "f5u2=7 }
} VZw( "a*TB
@Q TG
/** /C3=-Hp
* @return Returns the users. &/Tx@j^.C
*/ = `70]%
publicList getUsers(){ .RoO6:T6
return users; P_Po g^
} /kNr5s
aD0w82s]J
/** ka"jv"z
* @param page .8fOc.h8h
* The page to set. W6~<7
*/ ou96
P<B
publicvoid setPage(Page page){ Gz^g!N[
this.page = page; 24|:VxO
} ib uA~\5
:i?Z1x1`
/** U3A>#EV
* @param users +.[#C5
* The users to set. gy~M]u{
*/ :n>:*e@w%
publicvoid setUsers(List users){ ZhM-F0;`
this.users = users; o<T>G{XYB
} dI'C[.zp[
'Y>!xm
/** u4fTC})4{C
* @param userService vjbot^W9
* The userService to set. 6U# C
*/ Q;5aM%a`
publicvoid setUserService(UserService userService){ *1%=?:$(r6
this.userService = userService; b@5&<V;r2
} vJXd{iQE@C
} H+_oK
]/
r}03&h~Hc&
QT^(
oog=
I]ywO4
zXZy:SD
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, >-+MWu=
lL%7lO
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 G{ F>=z"(l
kZF\V7k
么只需要: {TUCa
java代码: {`l]RIig
c3oI\lU
qY#*zx
<?xml version="1.0"?> c|ZZ+2IYd
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _VR4|)1g
XTHrf'BU
1.0//EN" "http://www.opensymphony.com/xwork/xwork- } vcr71u
$#"}g#u
1.0.dtd"> ,3N8
z36ny o
<xwork> ux{OgFfi
-c|O!Lc-
<package name="user" extends="webwork- cDE?X o'!
'!IX;OSjH
interceptors"> Fd|:7NRA<
<*4=sX@
<!-- The default interceptor stack name FKL}6W:
"D@m/l
--> /j3oHi$
<default-interceptor-ref vR+(7^Yy
s?OGB}
name="myDefaultWebStack"/> F"B! r -J
?Vt$
<action name="listUser" r+$ 0u~^
etGquW.
class="com.adt.action.user.ListUser"> ?V*>4A
<param MV=.(Zs
*7!}[ v_
name="page.everyPage">10</param> u%ih7v!r\
<result <&W3\/xx
S2j7(T;~YB
name="success">/user/user_list.jsp</result> 0r+-}5aSl5
</action> d7KeJ$xy}p
y0A2{'w
</package> Z AZQFr'*
Q Z9)uI
</xwork> @JN%P}4)
4Ag+
!j7b7<wR
zhYE#hv2
f_;3|i
%!YsSk,
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 SOP=
X-6f
}3)$aI_
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。 F!a YK2
9(u2jbA
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 TD\QX2m
E*RP8
?]5wX2G^|J
/0@}7+&
_);1dcnR
我写的一个用于分页的类,用了泛型了,hoho wl(}F^:/`
=PO/Q|-v?
java代码: ?8vjHEE
_>3GNvS
!kmo%+
package com.intokr.util; (v(_XlMK
Prjl ;[I}
import java.util.List; 17};I7
G_dia6
/** eZ
]6Q
* 用于分页的类<br> ]G|@F
:
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >E)UmO{S
* u45e>F=
* @version 0.01 V|b?H6Q
* @author cheng zRf]SZ(tO
*/ YK"({Z>U
public class Paginator<E> { v
SWqOv$
privateint count = 0; // 总记录数 C5XCy%h
privateint p = 1; // 页编号 M~
*E!
privateint num = 20; // 每页的记录数 m=%W <8[V
privateList<E> results = null; // 结果 94K;=5h
Z.YsxbH3
/** #Oe=G:+A
* 结果总数 ugMJ}IGq
*/ C'zMOR6c
publicint getCount(){ tx5@r;
return count; -U;s,>\)
} KZD&Ih(vC
tK8\Ib J
publicvoid setCount(int count){ E}"&?oY
this.count = count; Xwx;m/
} kTFN.kQx@
1u&P,&T
/** P#EqeO
* 本结果所在的页码,从1开始 'n>|jw)
* $ g1p!
* @return Returns the pageNo. JTz1M~
*/ 1
C[#]krh
publicint getP(){ BDB-OJ
return p; ;39{iU.m
} h ]MSjC.X
UbMcXH8=F
/** !4*@H
* if(p<=0) p=1 ^z)lEO
* ]~a!O
* @param p xnh%nv<v{
*/ 1f}S:Z
publicvoid setP(int p){ jp[QA\
if(p <= 0) iB]kn(2C
p = 1; B /Dj2
this.p = p; c~$ipX
} aD3$z;E
8mCr6$|%
/** %*jpQOw
* 每页记录数量 MTLcLmdO
*/ v,>q]!
|a
publicint getNum(){ 2<