Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F=Xb_Gd`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 aEzf*a|fSV
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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 JFI*Pt;X9
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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 vw>(JCR
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分页支持类: Y;R,ph.a
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java代码: E-^(VZ_Xj
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package com.javaeye.common.util; 48z%dBmTT*
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import java.util.List; TfJ*G6\7e#
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publicclass PaginationSupport { rI\5djiYJ
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publicfinalstaticint PAGESIZE = 30; |(l]Xr&O
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privateint pageSize = PAGESIZE; LL);Ym9d
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privateList items; Lios1|5
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privateint totalCount; /&\V6=jA1
Pm#/j;
privateint[] indexes = newint[0]; )a0l:jEOc
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privateint startIndex = 0; Q\zaa9P
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public PaginationSupport(List items, int ;ZuHv {=
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totalCount){ J;<dO7 j5
setPageSize(PAGESIZE); fn/?I\
setTotalCount(totalCount); s#<fj#S
setItems(items); t{B@k[|
setStartIndex(0); dSKvs"
} 5s\;7>
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public PaginationSupport(List items, int VMF?qT3Nd
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totalCount, int startIndex){ W{Je)N
setPageSize(PAGESIZE); &u^]YE{
setTotalCount(totalCount); =c 9nC;C
setItems(items); '4 d4i
setStartIndex(startIndex); ysi=}+F.
} IAzFwlO9
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public PaginationSupport(List items, int fJ\?+,
] 7[#K^
totalCount, int pageSize, int startIndex){ *.eeiSi{
setPageSize(pageSize); E$z- |-{>
setTotalCount(totalCount); cQxUEY('+
setItems(items); TDZ==<C
setStartIndex(startIndex); @"h4S*U
} I@z@s}x>
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publicList getItems(){ qi~-<qW
return items; 3]'ab-,Vp
} t$,G%micj
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publicvoid setItems(List items){ Uc_}="
this.items = items; g$2#TWW5
} [;aM8N
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publicint getPageSize(){ 1P"{TMd?
return pageSize; QKEtV
} T^MY w
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publicvoid setPageSize(int pageSize){ !wUznyYwt
this.pageSize = pageSize; '/XP4B\(E
} h}'Hst
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publicint getTotalCount(){ $bKXP(
return totalCount; E@otV6Wk[@
} {S+?n[1r\
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publicvoid setTotalCount(int totalCount){ ud(0}[
if(totalCount > 0){ w%TrL+v
this.totalCount = totalCount; sZ&6g<8#y
int count = totalCount / ts(u7CJd
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pageSize; _1Rw~}O
if(totalCount % pageSize > 0) 4Dn&+=fq
count++; t
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indexes = newint[count]; Z5oDj|&l}
for(int i = 0; i < count; i++){ _#v"sGmN
indexes = pageSize * l]D$QT3
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i; j&/+/s9N
} lijTL-3
}else{ _:NQF7X#ug
this.totalCount = 0; OO?N)IB@
} :4)x
} ks phO-
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publicint[] getIndexes(){ nu+^D$ait
return indexes; 3rFku"zT$
} |xZu?)M4
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publicvoid setIndexes(int[] indexes){ 0+qC_ISns
this.indexes = indexes; o:cTc:l)
} @,= pG
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publicint getStartIndex(){ 9XQE5^
return startIndex; W+u,[_
} -0q|AB<
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publicvoid setStartIndex(int startIndex){ A{-S )Z3}
if(totalCount <= 0) fnr8{sr.2Z
this.startIndex = 0; OESKLjFt
elseif(startIndex >= totalCount) h#}w18l
this.startIndex = indexes 6W1+@
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[indexes.length - 1]; jyF*JQjK4
elseif(startIndex < 0) B_[I/ ?
this.startIndex = 0; $ S3b<]B
else{ Ap?,y?
this.startIndex = indexes JAjiG^]
?kZ-,@h:
[startIndex / pageSize]; 3mYW]
} `Rq|*:LV
} "XV@OjrE
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publicint getNextIndex(){ 6Hb a@Q1`
int nextIndex = getStartIndex() + z__t8yc3
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pageSize; E=,b;S-
if(nextIndex >= totalCount) Oprfp^L
return getStartIndex(); *szs"mQ/
else SX'NFdY
return nextIndex; CeOA_M
} Go:(R {P
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publicint getPreviousIndex(){ 3)CIqN
int previousIndex = getStartIndex() - aynaV
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pageSize; =AzkE]
if(previousIndex < 0) 05HCr"k
return0; GK,{$SC+=
else PX^k;
return previousIndex; uUHWTyoO
} 3SbZD
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} mh[,E8'd
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抽象业务类 }m?Ut|
java代码: =ZU!i0
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/** BcpbS%S
* Created on 2005-7-12 bp?TO]LH
*/ KK>jV
package com.javaeye.common.business; W!.FnM5x
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import java.io.Serializable; iNi1+sm
import java.util.List; LzLJ6A>;R
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import org.hibernate.Criteria; l}-k>fug
import org.hibernate.HibernateException; ziO(`"v
import org.hibernate.Session; fX,O9d$
import org.hibernate.criterion.DetachedCriteria; WW3Jxd
import org.hibernate.criterion.Projections; A_ &IK;-go
import %YF
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{_.(,Z{
org.springframework.orm.hibernate3.HibernateCallback; mMZrBz7r
import X#0yOSR
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org.springframework.orm.hibernate3.support.HibernateDaoS 9cN@y<_I
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upport; By!u*vSev
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import com.javaeye.common.util.PaginationSupport; +&f_k@+
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public abstract class AbstractManager extends tGl|/
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HibernateDaoSupport { ("}Hs[
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privateboolean cacheQueries = false; u&o4?]6
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privateString queryCacheRegion; a(O@E%|u
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publicvoid setCacheQueries(boolean e'G3\h}#
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cacheQueries){ \j)c?1*$
this.cacheQueries = cacheQueries; W2$rC5|
} BIx*(
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publicvoid setQueryCacheRegion(String |mWSS'7fI
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queryCacheRegion){ W6EEC<$JL
this.queryCacheRegion = t W
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queryCacheRegion; Xu_1r8-|=b
} r:0RvWif
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publicvoid save(finalObject entity){ VY~*QF~P
getHibernateTemplate().save(entity); =|$U`~YB
} L&NpC&>wD
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publicvoid persist(finalObject entity){ ';v2ld 9
getHibernateTemplate().save(entity); cJwe4c6.m
} IhSXU<]
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publicvoid update(finalObject entity){ :Zq?V`+M
getHibernateTemplate().update(entity); JDnWBE V
} ~/SLGyu
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publicvoid delete(finalObject entity){ ^"/TWl>jB
getHibernateTemplate().delete(entity); *CF80DJ
} ;VCFDE{K=
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publicObject load(finalClass entity, x3Fn'+
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finalSerializable id){ loq2+(
return getHibernateTemplate().load ^5 "yY2}-
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(entity, id); &];W#9"Z
} n.5M6i/~a
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publicObject get(finalClass entity, &V&beq4)p
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finalSerializable id){ 'S
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return getHibernateTemplate().get ,e`n2)
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(entity, id); xQ?$H?5B<
} d--6<_q
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publicList findAll(finalClass entity){ 4T)`%Oo<}
return getHibernateTemplate().find("from +['1~5
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" + entity.getName()); +W[{UC4b
} 0_^3
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publicList findByNamedQuery(finalString Gh{9nM_\"
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namedQuery){ KV{
return getHibernateTemplate #f=41d%
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().findByNamedQuery(namedQuery); 9dp4&&Z+F
} a)+*Gf7?
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publicList findByNamedQuery(finalString query, cUi6 On1C
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finalObject parameter){ vHPsHy7y
return getHibernateTemplate @2$Uk!
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().findByNamedQuery(query, parameter); Je'%EJ
} +y-3tcI)
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publicList findByNamedQuery(finalString query, li')U
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finalObject[] parameters){ ?6MUyH]a
return getHibernateTemplate 9I1`* 0A
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().findByNamedQuery(query, parameters); RSjcOQ8&.w
} v]q"{c/
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publicList find(finalString query){ VF<VyWFC0`
return getHibernateTemplate().find R\6dvd
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(query); _w5c-\-PUM
} ;t.)A3 PL
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publicList find(finalString query, finalObject x+Ly,9nc$
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parameter){ \/m-G:|
return getHibernateTemplate().find >8`;SEnv
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(query, parameter); %~Wr/TOt+
} !i{5mc\
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public PaginationSupport findPageByCriteria ICWHEot
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(final DetachedCriteria detachedCriteria){ Djp;\.$(
return findPageByCriteria gPpk0LZi
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); B|AIl+y
} }qhND-9#@
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public PaginationSupport findPageByCriteria \&v)#w
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(final DetachedCriteria detachedCriteria, finalint ~^g*cA
t}
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startIndex){ S)^eHuXPI
return findPageByCriteria jyRz53
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(detachedCriteria, PaginationSupport.PAGESIZE, c8o2* C$
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startIndex); H ;HFen|
} zK: 2.4
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public PaginationSupport findPageByCriteria bg*@N
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(final DetachedCriteria detachedCriteria, finalint Gfle"_4m8
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pageSize, drB$q[Ak9
finalint startIndex){ (%]M a
return(PaginationSupport) [5P1 pkZ
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getHibernateTemplate().execute(new HibernateCallback(){ )EsFy6K:
publicObject doInHibernate 3pkx3tp{
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(Session session)throws HibernateException { ZP4y35&%y
Criteria criteria = ^QTkre
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detachedCriteria.getExecutableCriteria(session); `S]DHxS
int totalCount = B!1L W4^
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((Integer) criteria.setProjection(Projections.rowCount 7}Jn`^!
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()).uniqueResult()).intValue(); T FK#ign
criteria.setProjection HhUk9 >7
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(null); Qy'-3GB
List items = 0&6(y*
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criteria.setFirstResult(startIndex).setMaxResults ]~'pYOB
-$f$z(h
(pageSize).list(); G>+iisb%
PaginationSupport ps =
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new PaginationSupport(items, totalCount, pageSize, n!?u/[@
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startIndex); xcXnd"YYE
return ps; 9P-I)ZqL
} $&0\BvS
}, true); Z+S1e~~
} R lmeZy4.
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public List findAllByCriteria(final (0S;eM&
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DetachedCriteria detachedCriteria){ ^A t,x
return(List) getHibernateTemplate &jF[f4:7
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().execute(new HibernateCallback(){ wB%;O `Oh
publicObject doInHibernate ;-{'d8
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(Session session)throws HibernateException { !u%XvxJwDb
Criteria criteria = I!g+K
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); E"t79dD
} [gE2;J0*
}, true); d>`s+B9K0
} Jgzg[6
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public int getCountByCriteria(final 7j{63d`2
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DetachedCriteria detachedCriteria){ ne'Y {n(8%
Integer count = (Integer) h8? E+0
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getHibernateTemplate().execute(new HibernateCallback(){ jH]?vpP
publicObject doInHibernate JO|xX<#:
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(Session session)throws HibernateException { sj% \lq
Criteria criteria = u~j&g
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detachedCriteria.getExecutableCriteria(session); N5@l[F7I
return sFonc
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criteria.setProjection(Projections.rowCount =_9grF-
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()).uniqueResult(); $or8z2d1
} 9{n?Jy
}, true); |Ht~o(]&&/
return count.intValue(); 2g_2$)2
} !l#n.Fx&3
} 5,K*IH
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用户在web层构造查询条件detachedCriteria,和可选的 A$XmO}+
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 T Ue=Yj
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PaginationSupport的实例ps。 +p_>fO
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ps.getItems()得到已分页好的结果集 aA&}=lm
ps.getIndexes()得到分页索引的数组 =F90SyzTy
ps.getTotalCount()得到总结果数 E|omC_h
ps.getStartIndex()当前分页索引 S"Mm_<A$@
ps.getNextIndex()下一页索引 OE_A$8L
ps.getPreviousIndex()上一页索引 ];au!
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Bq#B+JwX
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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 B/ACU
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一下代码重构了。 zFeo8S
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我把原本我的做法也提供出来供大家讨论吧: R7~#7qKQB
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首先,为了实现分页查询,我封装了一个Page类: k5]`:k6
java代码: 5Ak6 q(\
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/*Created on 2005-4-14*/ ,lr\XhO
package org.flyware.util.page; wA7^
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/** ])uhm)U@
* @author Joa ;`-@L
* k<!xOg
*/ -@yu 9=DT
publicclass Page { AWn$od`#s
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/** imply if the page has previous page */ },(Ln%M
privateboolean hasPrePage; ~xV|<;
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/** imply if the page has next page */ (SGU]@)g
privateboolean hasNextPage; rk .tLk
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/** the number of every page */ !_#2$J*s^D
privateint everyPage;
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/** the total page number */ xRPUGGv
privateint totalPage; ]J>{ZL
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/** the number of current page */
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privateint currentPage; \rY<DxtOq
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/** the begin index of the records by the current 3pk `&'
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query */ >pq= .)X}
privateint beginIndex; $ @Fvl-lK
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/** The default constructor */ 'SE?IE {
public Page(){ }Gg:y?
tX *}l|;(
} S,%BhQ[
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/** construct the page by everyPage 9$oU6#U,h
* @param everyPage 1feS/l$
* */ I-?Dil3
public Page(int everyPage){ Jt}0%C3d
this.everyPage = everyPage; >@wyiBU
} ?R VY%s;g
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/** The whole constructor */ "J(W)\
public Page(boolean hasPrePage, boolean hasNextPage, UOAL7
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int everyPage, int totalPage, ppu WcGo
int currentPage, int beginIndex){ :*MqYny&
this.hasPrePage = hasPrePage; >qhoGg
this.hasNextPage = hasNextPage; zOzobd
this.everyPage = everyPage; h8me.=S&
this.totalPage = totalPage; qS{E+) P
this.currentPage = currentPage; N!
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this.beginIndex = beginIndex; NHjZ`=Js
} pk,]yi,ZF
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/** f R?Xq@c
* @return \uTy\KA
* Returns the beginIndex. vOKWi:-U
*/ D3BT>zTGK
publicint getBeginIndex(){ <5wk~|@t
return beginIndex; #ovmX
} i^zncDMA
G$)f5_]7{
/** 9X- w5$<
* @param beginIndex SlRQi:
* The beginIndex to set. byW9]('e
*/ _R 6+bB$
publicvoid setBeginIndex(int beginIndex){ 7eyVm;LQD
this.beginIndex = beginIndex; |)pRkn8x
} WFTXSHcG
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/** 3r]:k)J
* @return Gec?
* Returns the currentPage. dvl'Sq<
*/ BlrZ<\-/
publicint getCurrentPage(){ c{X:0man
return currentPage; ZgP~VB0)$
} 'q_^28rK
S);SfNh%CL
/** (v'#~ )R_`
* @param currentPage
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* The currentPage to set. (WISf}[l;
*/ #S*`7MvM
publicvoid setCurrentPage(int currentPage){ $k|:V&6SV
this.currentPage = currentPage; N#Y|MfLc
} nbECEQ:|B
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/** Zr%,F[j?
* @return +6$ |No
* Returns the everyPage. ?b8 :
*/ 7l~d_<h
publicint getEveryPage(){ qZS]eQW.
return everyPage; FZ0wtS2
} fUg<+|v*
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/** Sl!#!FGI
* @param everyPage nN]GO}
* The everyPage to set. $q
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*/ fy6<KEea
publicvoid setEveryPage(int everyPage){ C2[* $ 1U
this.everyPage = everyPage; jgW-&nK!
} U_8 Z&
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/** $Sx(vq6(
* @return '<JNS8h
* Returns the hasNextPage. =sYUzYm
*/ Oe/&Ryj=mm
publicboolean getHasNextPage(){ 'BiR ,M$mY
return hasNextPage; pXy'S s@y
} EDA%qNd]j
Ki,SFww8r
/** v/m} {&K
* @param hasNextPage NR6wNz&81
* The hasNextPage to set. w!j 'k|b>
*/ J2BCaAwEP,
publicvoid setHasNextPage(boolean hasNextPage){ T@ 4R|P&{)
this.hasNextPage = hasNextPage; "?X,);5S
} 5{"v/nXV
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/** e2><Y<
* @return nr{#Krkb
* Returns the hasPrePage. '
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*/ $0mR_pA\fW
publicboolean getHasPrePage(){ hb. ^&
return hasPrePage; ^ 5D%)@~
} AbExJ~JV\g
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/** k',#T932x1
* @param hasPrePage }mYxI^n
* The hasPrePage to set. [pRRBMho
*/ N8E
publicvoid setHasPrePage(boolean hasPrePage){ 3!u`PIQv
this.hasPrePage = hasPrePage; z|$M,?r'
} */6lyODf
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/** ;H4 s[#K
* @return Returns the totalPage. A/c #2
* Q;xJ/4 Z"
*/ r6QshCA"
publicint getTotalPage(){ @dyh:2!
return totalPage; {6tj$&\)
} `6:B0-r
jAcrXB*
/** j2RdBoCt
* @param totalPage jf^BEz5
* The totalPage to set. S
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*/ PWBcK_4i%
publicvoid setTotalPage(int totalPage){ ,x=S)t
this.totalPage = totalPage; @Cml^v@`L
} G`Df'Yy
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} 2oo/KndU
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 WS ^,@>A
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个PageUtil,负责对Page对象进行构造: }0IeKpu5
java代码: ,
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/*Created on 2005-4-14*/ 4nrn
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package org.flyware.util.page; +ag_ w}
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import org.apache.commons.logging.Log; TI|h
import org.apache.commons.logging.LogFactory; ALQ-aXJ
bd\%K`JQ{
/** P~M[i9 V
* @author Joa #U(kK(uO
* bq2f?uD-}
*/ Q2!5
publicclass PageUtil { EsS$th)d
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privatestaticfinal Log logger = LogFactory.getLog
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"AP$)xM-:
(PageUtil.class); Q5b9q$L$
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/** 8iTB
* Use the origin page to create a new page S Rk%BJ? ~
* @param page BwkY;Ur/AL
* @param totalRecords guG&3{&\s
* @return ?rjB9AC_;t
*/ la}cGZ; p.
publicstatic Page createPage(Page page, int osl\j]U8
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totalRecords){ }<YU4EW
return createPage(page.getEveryPage(), (:I]v_qEYS
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page.getCurrentPage(), totalRecords); -p?&vQDo`
} Gr 4v&Mz:
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/** !B92W
* the basic page utils not including exception VEp cCK
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handler ,kf.'N
* @param everyPage =P%&]5ts
* @param currentPage BA2J dU
* @param totalRecords ?;_*8Doq-a
* @return page *NG\3%}%|@
*/ 8ok=&Gq4
publicstatic Page createPage(int everyPage, int M!kSt1
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currentPage, int totalRecords){ b8_F2
everyPage = getEveryPage(everyPage); "X^<g{]
currentPage = getCurrentPage(currentPage); ]B UirJ,2
int beginIndex = getBeginIndex(everyPage, B]H8^
$C sE[+k1
currentPage);
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int totalPage = getTotalPage(everyPage, 4=o vm[
zPxR=0|
totalRecords); haY]gmC
boolean hasNextPage = hasNextPage(currentPage, }W'4(V;:
araXE~Ac
totalPage); bU}v@Uk
boolean hasPrePage = hasPrePage(currentPage); P%)r4+at
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returnnew Page(hasPrePage, hasNextPage, &y}7AV
everyPage, totalPage, oOaFA+0x
currentPage, &92/qRh7
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beginIndex); 4qz+cB_
} ,f2oO?L}
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privatestaticint getEveryPage(int everyPage){ YR*gOTD
return everyPage == 0 ? 10 : everyPage; _FYA? d}
} >x JzV
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privatestaticint getCurrentPage(int currentPage){ ^8;MY5Wbs
return currentPage == 0 ? 1 : currentPage; K^U="
} kqm(D#
KCW2
UyE]
privatestaticint getBeginIndex(int everyPage, int $Yt|XT+!&
(0H=f6N
currentPage){ jwT` Z
return(currentPage - 1) * everyPage; v>#Njgo
} Yu\$Y0 {]
Ig t*8px
privatestaticint getTotalPage(int everyPage, int Ba@~:
(<r)xkn
totalRecords){ T2MC`s|`
int totalPage = 0; @T~XwJ~
0#9H;j<Op
if(totalRecords % everyPage == 0) b^Z2Vf:k]
totalPage = totalRecords / everyPage; <7VLUk}
else /iFn=pk1?
totalPage = totalRecords / everyPage + 1 ; s|e.mZk/
Tv DSs])
return totalPage; NgDhdOB
} SjB"#E)
ID2->J
privatestaticboolean hasPrePage(int currentPage){ x.*^dM@V
return currentPage == 1 ? false : true; A.vAk''(}+
} Y2x|6{ #
UHZ&7jfl
privatestaticboolean hasNextPage(int currentPage, x 4+WZYv3
94+^K=lAX
int totalPage){ ZLT?G
return currentPage == totalPage || totalPage == \Nt
5TG_
/e0B$UymFu
0 ? false : true; b!]O]dk#
} oZiW4z*Wh
;_I>`h"r
%]_: \!
} v`Jt+?I
Iw`tbN
L[
* @4@eQF
ayA;6Qt
<{kPa_`'
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。 vTK%4=|1}!
$Q/@5f'T`9
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 Z<i}XCE
JD$g%hcVZa
做法如下: CM_hN>%w[
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 tn5%zJ#+
r%.k,FzGZY
的信息,和一个结果集List: (SyD)G\rj
java代码: y(J~:"}7)
=~+ WJN
Ab@G^SLX
/*Created on 2005-6-13*/ tP@NQCo
package com.adt.bo; ( V4Ppg
Y"mFUW4
import java.util.List; INN}xZ
]Lub.r
import org.flyware.util.page.Page; $X#y9<bW
^O_Z5NbC3
/** SboHo({5VA
* @author Joa =P(*j7=
*/ uyWheR
publicclass Result { PR@6=[|d
>5CK&6
private Page page; o]<Z3)
f;{Q ~
private List content; +HS]kF H
pp@
Owpb
/** v$]B;;[A
* The default constructor N{v)pu.
*/ OXEEpoU?V
public Result(){ 8ZY]-%
super(); WQ9e~D"
} jKq*@o~}
(DiduSJ
/** <F7a!$zQ
* The constructor using fields %hVR|K|J
* :*Wq%Y=
* @param page 0fOhCxtL@
* @param content g+#awi7
*/ sycAAmH<
public Result(Page page, List content){ j.q}OK
this.page = page; #LasTN9
this.content = content; D>7a0p784
} O <Rh[Aqn
KqFI2@v
/** ~XOmxz0
* @return Returns the content. .ck?JXg
*/ 4mvR]:G
publicList getContent(){ 1&dtq,|N
return content; :F:1(FDP
} Xd(^7~i
hN3FH#YO
/** F rckA
* @return Returns the page. U,#~9
*/ +M-tYE
5n
public Page getPage(){ hE&6;3">
return page; B\Nbt!Ps
} "Vp
nr +6
\FsA-W\X
/** 8US#SI'x
* @param content #gC[L=01
* The content to set. -#ZLu.
*/ Vm%G
q
public void setContent(List content){ gC1LQ!:;Oi
this.content = content; z.8/[)
} vG_R( ]d
FOk&z!xYKd
/** D;R~!3f./b
* @param page ,U\s89
* The page to set. 7"(Zpu
*/ ~(R=3
publicvoid setPage(Page page){ *V2;ds.~
this.page = page; Q a (Sb
} g#$ C8k
} V?Jy
1$0Kvvg[
gy.UTAs
N
R%jOgZG
@;4;72@O
2. 编写业务逻辑接口,并实现它(UserManager, @vl$[Z|
'FXM7D
UserManagerImpl) a
8k2*u
java代码: aF
2vgE\
L3%frIUd
;oOTL'Vu
/*Created on 2005-7-15*/ _pTcSp3
package com.adt.service; yI^Yh{
$}&a*c>
import net.sf.hibernate.HibernateException; vFk@
d'';0[W)
import org.flyware.util.page.Page;
9)VAEyv
g4ZUh@b~
import com.adt.bo.Result; :`N&BV
k?fz @H8D(
/** }+!"mJx@
* @author Joa bL7Gkbs&|
*/ a}@b2Wc*
publicinterface UserManager { SMZ*30i
5sJ>+Rg
public Result listUser(Page page)throws |Y!^E %*
C98F?uo%Q
HibernateException; E>_Rsw *
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} 3
`_/h' ~
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d_,My lk
cP?GRMX@}
@(#vg\UH
java代码: 0cmd +`
U;bx^2<m
Nw. )O
/*Created on 2005-7-15*/ Ic&~iqQ
package com.adt.service.impl; )|=1;L
E 3'I;
import java.util.List; }n&nuaj
v`oilsrc
import net.sf.hibernate.HibernateException; `/WxEu3
e`0C0GaP
import org.flyware.util.page.Page; :P-H8*n""
import org.flyware.util.page.PageUtil; iM8Cw/DS
[k
7HLn)
import com.adt.bo.Result; dz@+ jEV
import com.adt.dao.UserDAO; #K^hKx9
import com.adt.exception.ObjectNotFoundException; 0o8`Y
import com.adt.service.UserManager; XuP%/\
7FH-l(W
/** O]XRalkEM
* @author Joa p.:|Z-W$
*/ ]pm/5|
publicclass UserManagerImpl implements UserManager { 1HO;~NJ]m
(7X
private UserDAO userDAO; X8tPn_`x
Pjh;;k|V
/** &~eCDlX/
* @param userDAO The userDAO to set. L$Z!
*/ B}04E^
publicvoid setUserDAO(UserDAO userDAO){ V~PGmn[V
this.userDAO = userDAO; 5 51_;,t
} }h1BAKg
6OE
xAn8
/* (non-Javadoc) ddL3wQ
* @see com.adt.service.UserManager#listUser iU+SXsXLR4
Gw)y<h
(org.flyware.util.page.Page) 6`2i'flv
*/ 5%D`y|
public Result listUser(Page page)throws P:g!~&Q
7y^)n<'co
HibernateException, ObjectNotFoundException { JA{kifu0+
int totalRecords = userDAO.getUserCount(); ,%Z&*/*Oh
if(totalRecords == 0) f/L8usBXq
throw new ObjectNotFoundException kt
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D;JZ0."
("userNotExist"); ^%*qe5J
page = PageUtil.createPage(page, totalRecords); g Nz
List users = userDAO.getUserByPage(page); ty!DMg#
returnnew Result(page, users); r7VBz_Q
} F$>#P7ph\a
=0&XdxX
} :&5u)
e }O&_j-
kPOk.F%)
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 /7B3z}rd
qh bagw~
询,接下来编写UserDAO的代码: 3B[tbU(
3. UserDAO 和 UserDAOImpl: !rgXB(
java代码: &T-:`(
$
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dw#pObH|`
/*Created on 2005-7-15*/ 3q'nO-KJ
package com.adt.dao; E>@]"O)=M,
1grcCL
q
import java.util.List; l
VB^1wm
import org.flyware.util.page.Page; L?N:4/0;!
860y9wzU
import net.sf.hibernate.HibernateException; ZLaht(`+
W SvhC
/** TH>uL;?=
* @author Joa ;U0w<>4L
*/ Ku6ndc
publicinterface UserDAO extends BaseDAO { uj}%S_9
XwIHIG}
publicList getUserByName(String name)throws U&^(%W#
e}gGl<((g
HibernateException; Lz9|"F"V
fZs}u<3Q)
publicint getUserCount()throws HibernateException; mr>E'd.'
{niV63$m
publicList getUserByPage(Page page)throws 9-#=xE9'U
c-~i=C]
HibernateException; ).Z
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3kr.'O
} *ax&}AHK[/
4M$"0}O;[h
FKtCUq,:
f#38QP-T
c[6<UkH7
java代码: }P!:0w3
*wdNZ
)CH\]>-FO
/*Created on 2005-7-15*/ @gx]3t*]I
package com.adt.dao.impl; fsKZ
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import java.util.List; 9$sx+=(
IYr4
import org.flyware.util.page.Page; TY+Rol;!
>U:.5Tch'V
import net.sf.hibernate.HibernateException; Y,KSr|vG
import net.sf.hibernate.Query; z4[8*}
gfXit$s
import com.adt.dao.UserDAO; RLh%Y>w
d~CZ9h
/** ,PWMl[X
* @author Joa (Kkqyrb
*/ + VhD]!
public class UserDAOImpl extends BaseDAOHibernateImpl x1+ V
}1Hy[4B(k\
implements UserDAO { N,ihQB5
s9b+uUt%
/* (non-Javadoc) gr>>]C$
* @see com.adt.dao.UserDAO#getUserByName 8(@(G_skp
bmRp)CYd
(java.lang.String) ynq^ztBVe
*/ l\bgp3.+
publicList getUserByName(String name)throws I(Q3YDdb
F`f8q\Fc
HibernateException { r[&/*~xL
String querySentence = "FROM user in class H3|x
V(!-xu1,
com.adt.po.User WHERE user.name=:name"; T;Ra/H
Query query = getSession().createQuery ?h-:,icR
@3Mp>u/
(querySentence); eBlB0P
query.setParameter("name", name); JN<u4\e{-&
return query.list(); y}>bJ:
} G4K3qD#+H
S4>1 d-
/* (non-Javadoc) k
3oR:
* @see com.adt.dao.UserDAO#getUserCount() L%[b6<
*/ I#:4H2H6
publicint getUserCount()throws HibernateException { 5uvFCY./c
int count = 0; UV)!zgP
String querySentence = "SELECT count(*) FROM F@@6D0\X?
sG k'G573
user in class com.adt.po.User"; "D/\&1.&
Query query = getSession().createQuery b~EA&dc
9d >AnTf&H
(querySentence); gO]jeO
count = ((Integer)query.iterate().next \oV g(J&o
y(Ck j"
()).intValue(); LLW\1 cxi
return count; (Q][d+} /
} $n9Bp'<
k|F TT
/* (non-Javadoc) ^@AIXBe
* @see com.adt.dao.UserDAO#getUserByPage <lHVch"(^$
/UPe@
(org.flyware.util.page.Page) ZuVucP>>_d
*/ ^@n?&
publicList getUserByPage(Page page)throws i.6+CA
fg0zD:@rA
HibernateException { Jz6zJKcA
String querySentence = "FROM user in class C.q4rr
`l`)Cs;a
com.adt.po.User"; J^<}fRw
Query query = getSession().createQuery Ga#5xAI{a
4ROuy+Ms'
(querySentence); $"6O92G(hJ
query.setFirstResult(page.getBeginIndex()) e?)ic\K
.setMaxResults(page.getEveryPage()); -k"5GUc|
return query.list(); ?'r=>'6D
} NE2P
"mY
DE _<LN
} Avn)%9
w{5v*SHl}`
tw%z!u[a
sAfNu~d
[5sa1$n96G
至此,一个完整的分页程序完成。前台的只需要调用 byetbt(IF
3"y,UtKGa
userManager.listUser(page)即可得到一个Page对象和结果集对象 f{eMh47 NC
~_Q1+ax}
的综合体,而传入的参数page对象则可以由前台传入,如果用 55#s/`gd)^
'n4$dv%q
webwork,甚至可以直接在配置文件中指定。 El:&
v[I,N$:
下面给出一个webwork调用示例: E-J<%+
java代码: T+U,?2nF:
-TU^*
EsKOzl[c:
/*Created on 2005-6-17*/ X|Z2"*;b`
package com.adt.action.user; r\DA&b
, UiA?7k
import java.util.List; C)xM>M_CB
6A,-?W'\
import org.apache.commons.logging.Log; 2E*h,Mo
import org.apache.commons.logging.LogFactory; o"-*,:Qe
import org.flyware.util.page.Page; 2{fPQQ;#
$F/Uk;*d!
import com.adt.bo.Result; J2d3&6
import com.adt.service.UserService; <Gkmk?x`A
import com.opensymphony.xwork.Action; 0\2#(^
Hm*?<o9mxC
/** 6
r}R%{
* @author Joa deVbNg8gs
*/ \1R<GBC4
publicclass ListUser implementsAction{ %6eQ;Rp*
moT*r?l
privatestaticfinal Log logger = LogFactory.getLog NT&skrzW
h#Q Sx@U6
(ListUser.class); fA{t\
QssU\@/Q
private UserService userService; B(B77SOb
w:+wx/\
private Page page; |QcE5UC
('Doy1L
privateList users; ^a{cK
`D~wY^q{
/* nTQ&nu!
* (non-Javadoc) Kdr7JQYzuz
* \PJpy^i
* @see com.opensymphony.xwork.Action#execute() \mGok<b4
*/ M'-Z"
publicString execute()throwsException{ 9w:9XziT
Result result = userService.listUser(page); LCouDk(=`
page = result.getPage(); Y `ySNC
users = result.getContent(); s !XJ
return SUCCESS; nXFPoR)T
} 2SV}mK U
pf[m"t6G~
/** Oi-=
Fp
* @return Returns the page. lJIcU
RI4
*/ [JyhzYf\
public Page getPage(){ z8-dntkf
return page; TQ&1!~L*
} Z0#&D&2sV
]**h`9MF
/** lV
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* @return Returns the users. -~=?g9fGm6
*/ tQ7:4._
publicList getUsers(){ vp|'Yy(9z
return users; Xdl7'~k
} Ahf71YP
V7(-<})8
/** rm?C_
* @param page ?(R!BB
* The page to set. Fz.Ij'8.H
*/ Hzc5BC
publicvoid setPage(Page page){ 6QM$aLLP?
this.page = page; [~{'"-3L0
} v9"|VhZ
U
ljWBd
/** )\RG
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* @param users =Vat2'>+
* The users to set. ;}KT 3Q<^
*/ G(;R+%pu
publicvoid setUsers(List users){ Ny` =]BA
this.users = users; des.TSZ
} 1uco{JX<S
U%r|hn3
/** :`B70D8ku
* @param userService 51gSbkVX
* The userService to set. @p%WFNR0
*/ Pe/8=+qO
publicvoid setUserService(UserService userService){ gN;
E}AQt
this.userService = userService; AwtiV-w
} XImX1GH
} \OE,(9T2P.
~c`%k>$
MGLcM&oR
LZ}m;
b ,e"x48q
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, utU;M*
^H`4BWc
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 $EG9V++b3
V='A;gs
么只需要:
4 z^7T
java代码: ]ONBr(M\
dR!x)oO=
Hq
aay
<?xml version="1.0"?> UetI4`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ]jSRO30H3<
JH._/I
1.0//EN" "http://www.opensymphony.com/xwork/xwork- `_e5pW=:>
BVG.ZZR})
1.0.dtd"> 4ufT-&m};s
.^8rO,H[
<xwork> lUIh0%O
[&pMU)
<package name="user" extends="webwork- 4m!w<c0NL
w ufQyT`
interceptors"> A"/|h].
rN'8,CV
<!-- The default interceptor stack name w1LZ\nA<
]JQ}9"p=5
--> qOflvf
<default-interceptor-ref \$!D^%~;
:A+}fBIN
name="myDefaultWebStack"/> !b?cY{
{Ga=;0
<action name="listUser" 45H9pY w
5[]Yx l
class="com.adt.action.user.ListUser"> Q@[ (0R1
<param N!./u(b
R-tZC9
@
name="page.everyPage">10</param> ko"xR%Q
<result MS\?+8|SV(
[Pl''[
name="success">/user/user_list.jsp</result> p@ U[fv8u
</action> [U:P&)
N%9?8X[5
</package> AWg'J
6Zx5^f(qd
</xwork> Cx&l0ZXHEX
|CAMdU
Sa@T#%oU
Ymf@r?F<
e.W <pI,
zU'7x U-
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 .yHi"ss3
!6hV|2aJy
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 JvkTfTE7
BS%pS(
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 D^6Q`o
'7g]@Q7
IY|`$sHb
.)<l69ZD Z
WM7LCP
我写的一个用于分页的类,用了泛型了,hoho 0"Zxbgu)
4'td6F
java代码: q2s=>J';
dptfIBYc+
o#>Mf464I
package com.intokr.util; sRZ?Ilua6
([#'G+MC&