Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 d_AK`wR
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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 `k=bL"T>\
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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 E'v_#FLvR
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分页支持类: AK&S5F>D+B
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java代码: B||*.`3gN
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package com.javaeye.common.util; &Flglj~7l
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import java.util.List; t2EHrji~
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publicclass PaginationSupport { w3#Wh|LQ-
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publicfinalstaticint PAGESIZE = 30; W!%]_I!&K
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privateint pageSize = PAGESIZE; 0n@rLF
#%`|~%`{:
privateList items; un shH <
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privateint totalCount; ?;KKw*
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privateint[] indexes = newint[0]; &yGaCq;0
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privateint startIndex = 0; _ 6O\W%it
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public PaginationSupport(List items, int D Gr>
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totalCount){ yN~dU0.G6!
setPageSize(PAGESIZE); ^w(p8G_-w
setTotalCount(totalCount); s<*XNNE7
setItems(items); 0F@"b{&0
setStartIndex(0); |w_7_J2
} q:l>O5
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public PaginationSupport(List items, int tDSJpW'd
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totalCount, int startIndex){ =fu
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setPageSize(PAGESIZE); w<zIAQN
setTotalCount(totalCount); Ks=>K(V6
setItems(items); h lkn%
setStartIndex(startIndex); W;_nK4$%'
} q/4YS0CqE
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public PaginationSupport(List items, int Rz(QC\(
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totalCount, int pageSize, int startIndex){ 'I_Qb$
setPageSize(pageSize); 0zo?eI
setTotalCount(totalCount); 9dFy"yxYa
setItems(items); +cIUGFp}
setStartIndex(startIndex); k9)jjR*XxG
} PH `9MXh
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publicList getItems(){ ^m?KRm2
return items; P9=?zh6G.
} W)9K`hM6
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publicvoid setItems(List items){ Vm%1> '&
this.items = items; $P>`m$(8
} ${+ @gJ+S
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publicint getPageSize(){ 9[1`jtm
return pageSize; cj+ FRG~u
} i%ZW3MrY~
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publicvoid setPageSize(int pageSize){ TftHwe):V
this.pageSize = pageSize; L~(_x"uXd
} Ae69>bkE0
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publicint getTotalCount(){ =g/{%;
return totalCount; kHXL8k#T
} SfgU`eF%B
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publicvoid setTotalCount(int totalCount){ C3< m7h
if(totalCount > 0){ 8i6Ps$T
this.totalCount = totalCount; v[#9+6P=
int count = totalCount / hfnN@Kg?B}
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pageSize; .gG1kW A-
if(totalCount % pageSize > 0) R>,:A%?^b5
count++; io,M{Ib
indexes = newint[count]; i-bJS6
for(int i = 0; i < count; i++){ wB.Nn/p
indexes = pageSize * K)qF+Vb^j
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i; .jS~By|r
} V2$h8\a
}else{ RRmLd/(
this.totalCount = 0; 1&^MfP}
} d@ Y}SWTB
} ]04e1F1J
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publicint[] getIndexes(){ j{Hao\F8
return indexes; oo.! .Kv
} _cy2z
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publicvoid setIndexes(int[] indexes){ A]YVs
this.indexes = indexes; YGv<VOWG2
} &07]LF$]
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publicint getStartIndex(){ vr0WS3
return startIndex; xZ|Y?R5m
} GytXFL3`:
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publicvoid setStartIndex(int startIndex){ /rq VB|M
if(totalCount <= 0) S|apw7C
this.startIndex = 0; m>4ahue$
elseif(startIndex >= totalCount) q6_u@:3u
this.startIndex = indexes JL\w_v
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[indexes.length - 1]; xqC+0{]y
elseif(startIndex < 0) [F*.\
this.startIndex = 0; ?shIj;c[
else{ A3B56K
this.startIndex = indexes vk*=4}:
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[startIndex / pageSize]; _@
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} wNQ*t-K
} p3]_}Y
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publicint getNextIndex(){ ?*?RP)V
int nextIndex = getStartIndex() + sXi=70o
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pageSize; yHHt(GM|o
if(nextIndex >= totalCount) #{k|I$
return getStartIndex(); K$ M^gh0
else qw@puw@D
return nextIndex; U+)xu>I
} C0S^h<iSe*
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publicint getPreviousIndex(){ pY_s*0_
int previousIndex = getStartIndex() - _Qh
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pageSize; BNd^qB ?
if(previousIndex < 0) \e!vj.PU
return0; OfctoPP _0
else M7ers|&{
return previousIndex; 0PU8#2pR
} UlAzJO6"
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} UJfEC0
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抽象业务类 UB 6mqjPK
java代码: K'X2dG*
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/** ccLq+a|
* Created on 2005-7-12 9G{;?c
*/ a@\D$#2r
package com.javaeye.common.business; Pu"R,a
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import java.io.Serializable; rS4@1`/R
import java.util.List; vG;zJ#c
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import org.hibernate.Criteria; hGbj0
import org.hibernate.HibernateException; '@jXbN
import org.hibernate.Session; \MjJ9u `8
import org.hibernate.criterion.DetachedCriteria; NPd%M
import org.hibernate.criterion.Projections; =JKv:</.G
import mt5KbA>nU
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org.springframework.orm.hibernate3.HibernateCallback; 6ezS {Q
import l5g$vh\aQ]
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org.springframework.orm.hibernate3.support.HibernateDaoS d'/TdVM
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upport; $ &P>r
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import com.javaeye.common.util.PaginationSupport; _R.B[\r@
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public abstract class AbstractManager extends }|5VRJA
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HibernateDaoSupport { e.@uhB.
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privateboolean cacheQueries = false; 05snuNt]-
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privateString queryCacheRegion; +V{7")px6
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publicvoid setCacheQueries(boolean `2`\]X_A{
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cacheQueries){ @BrMl%gV
this.cacheQueries = cacheQueries; 7<jZ`qdq_
} FL8g5I
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publicvoid setQueryCacheRegion(String esHQoIhd
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queryCacheRegion){ Gg~QAsks
this.queryCacheRegion = zfwS
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queryCacheRegion; @#P,d5^G
} vjQb%/LWl
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publicvoid save(finalObject entity){ Kh4$ wwn
getHibernateTemplate().save(entity); +<}0|Xl&
} m!W3Cwz\&
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publicvoid persist(finalObject entity){ *J+_|_0nlW
getHibernateTemplate().save(entity); f]G>(V=i
} !^v5-xO?rP
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publicvoid update(finalObject entity){ {q<03d~9|G
getHibernateTemplate().update(entity); zOV=9"~{
} j:}D Bk
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publicvoid delete(finalObject entity){
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getHibernateTemplate().delete(entity); t^[8RhD
} v3GwD00
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publicObject load(finalClass entity, Z0`T\ay
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finalSerializable id){ {tThy#
return getHibernateTemplate().load -F=v6N {
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(entity, id); "Tm[t?FMbe
} ,^gyH
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publicObject get(finalClass entity, PG8^.)]M
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finalSerializable id){ y!5$/`AF
return getHibernateTemplate().get (ewe"N+
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(entity, id); e5.h ?
} K9vIm4::d$
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publicList findAll(finalClass entity){ =l.+,|ZH!
return getHibernateTemplate().find("from etd&..]J
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" + entity.getName()); (ZL sB{r^
} A>[|g`;t
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publicList findByNamedQuery(finalString %lX%8Z$v
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namedQuery){ -QyhwG=
return getHibernateTemplate CiR%Ujf
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().findByNamedQuery(namedQuery); ]`bQW?
} 6G}+gqbX
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publicList findByNamedQuery(finalString query, tX!nsm1
p~ .8\bI=
finalObject parameter){ hoT/KWD,
return getHibernateTemplate .))v0
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().findByNamedQuery(query, parameter); G&;j6<h l
} be e5
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publicList findByNamedQuery(finalString query, % aUsOB-RV
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finalObject[] parameters){ DAg58
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return getHibernateTemplate ,*]d~Y
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().findByNamedQuery(query, parameters); sz--27es
} __[xD\ES
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publicList find(finalString query){ zZiJ 9 e
return getHibernateTemplate().find m=Q[\.Ra
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(query); l88A=iLgv
} kD) $2I?
}pa9%BQI
publicList find(finalString query, finalObject v`V7OD#:j]
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parameter){ >a1{397Y}
return getHibernateTemplate().find ;.wX@
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(query, parameter);
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} M(d6Z2ibh
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public PaginationSupport findPageByCriteria YUQtMf9
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(final DetachedCriteria detachedCriteria){ N$TL;T>
return findPageByCriteria ;pD)m/$h`
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); q>s-Y|
} 4wi(?
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public PaginationSupport findPageByCriteria =SD\Q!fA
\<vNVz7.D
(final DetachedCriteria detachedCriteria, finalint WZ!WxX>zO
-
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startIndex){ yAL1O94
return findPageByCriteria "+?Cz!i
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(detachedCriteria, PaginationSupport.PAGESIZE, ^). )
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startIndex); H0a/(4/xg
} CzV(cSS9-
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public PaginationSupport findPageByCriteria Jti(b*~
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(final DetachedCriteria detachedCriteria, finalint 0)Rw|(Fpo]
_ nP;Fx
pageSize, yMLOUUWa8x
finalint startIndex){ >QHo@Zqj(
return(PaginationSupport) Gg\G'QU
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getHibernateTemplate().execute(new HibernateCallback(){ 7ou46v|m5
publicObject doInHibernate VGw(6`|!
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(Session session)throws HibernateException { ;Qi }{;+
Criteria criteria = ~#}Dx
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detachedCriteria.getExecutableCriteria(session); i`)!X:j
int totalCount = tvX>{-M
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((Integer) criteria.setProjection(Projections.rowCount j%<}jw[2
6AN)vs}
()).uniqueResult()).intValue(); yBLUNIr
criteria.setProjection }<MR`h1
+:6Ii9GN
(null); Lt#'W
List items = Sx]
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criteria.setFirstResult(startIndex).setMaxResults 'mdM q=VI
oKFT?"[X
(pageSize).list(); JO@Bf
PaginationSupport ps = O`cu_
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new PaginationSupport(items, totalCount, pageSize, g^kx(p<u`
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startIndex); :f'&z47
return ps; '#O_}|ZN
} *jzLFuWIG
}, true); "`A :(<x
} !c<w SQ,
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public List findAllByCriteria(final pz_e =xr
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DetachedCriteria detachedCriteria){ 'ul\Q`N3
return(List) getHibernateTemplate K8^kJSF\
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().execute(new HibernateCallback(){ 0"xPX#Cvj
publicObject doInHibernate *i$ePVU
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(Session session)throws HibernateException { ID};<[
Criteria criteria = S"snB/
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detachedCriteria.getExecutableCriteria(session); `PI(%N
return criteria.list(); XeUC0K[D
} daZQz"PP
}, true); )_jSG5k
} =Pe><k
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public int getCountByCriteria(final ,:v&4x&=
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DetachedCriteria detachedCriteria){ KA]*ox6j;
Integer count = (Integer) yno(' 1B@
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getHibernateTemplate().execute(new HibernateCallback(){ |bZM/U=
publicObject doInHibernate m.%`4L^`T
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(Session session)throws HibernateException { #y"=Cz=1u7
Criteria criteria = ,*,sw:=2
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detachedCriteria.getExecutableCriteria(session); g?/XZ5$a5
return ){Mu~P
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criteria.setProjection(Projections.rowCount _JGs}aQ
j kn^Z":
()).uniqueResult(); {^q)^<#JT
} z>vtEV))
}, true); +6W(z3($
return count.intValue(); c^I0y!
} e`UQz$4!
} 8IY19>4'5J
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用户在web层构造查询条件detachedCriteria,和可选的 T|'&K:[TJ
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 )ctr"&-
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PaginationSupport的实例ps。 %l9$a`&
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ps.getItems()得到已分页好的结果集 mv
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ps.getIndexes()得到分页索引的数组 ~I_owCVZ
ps.getTotalCount()得到总结果数 ahIE;Y\j'
ps.getStartIndex()当前分页索引 mVH,HqsXa
ps.getNextIndex()下一页索引 H:oQ
ps.getPreviousIndex()上一页索引 SX+RBVZU
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2:
连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 RtF8A5ys
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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 ]rX9MA6
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一下代码重构了。 o)]FtL:mm
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我把原本我的做法也提供出来供大家讨论吧: i2F(GH?p[
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首先,为了实现分页查询,我封装了一个Page类: xks?y.wA
java代码: Lar r}o=
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/*Created on 2005-4-14*/ IcoowZZ
package org.flyware.util.page; 70iH0j)
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/** TgaYt\"i[
* @author Joa |>utWT]S
* \|+/0USn
*/ >[3X]n,0
publicclass Page { uW[3G
dtW0\^ .L
/** imply if the page has previous page */ #EwK"S~
privateboolean hasPrePage; '
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/** imply if the page has next page */ yq*JdTF
privateboolean hasNextPage; fi=?n{e'
H-&3}
/** the number of every page */ zl)&U=4l
privateint everyPage; YN#XmX%
:WX0,-Gn
/** the total page number */ !C`20,U
privateint totalPage; +i)AS0?d
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/** the number of current page */ /yK"t<p
privateint currentPage; @36S}5Oa
zh?4K*>.k
/** the begin index of the records by the current v ($L
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query */ ~gt3Omh
privateint beginIndex; +qE']yzm!
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/** The default constructor */ nEVbfNo0
public Page(){ JD&U}dJ
#:
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} )0|):g
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/** construct the page by everyPage Wm>b3:
* @param everyPage Q7k.+2
* */ x7gjG"V
public Page(int everyPage){ ak2dn]]D
this.everyPage = everyPage; d
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} uGCtLA+sL
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/** The whole constructor */ ,wTg$g-$
public Page(boolean hasPrePage, boolean hasNextPage, B/_6Ieb+
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int everyPage, int totalPage, )Pa*+ew7
int currentPage, int beginIndex){ =c]a
{|W?
this.hasPrePage = hasPrePage; H5p5S\g-)
this.hasNextPage = hasNextPage; \\s?B K
this.everyPage = everyPage; vzy!3Hiw
this.totalPage = totalPage; <(uTst
this.currentPage = currentPage; J0qXtr%h\
this.beginIndex = beginIndex; V/&o]b
} /s8/q2:
MCd F!{
/** i*
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* @return "aA_(Ydzj
* Returns the beginIndex. d5'
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*/ #NMJZ
publicint getBeginIndex(){ m+7`\|`jQ
return beginIndex; q\_DJ)qpn
} <i7agEdZD
/&QQ p3
/** x_|>n<Z
* @param beginIndex qOgtGN}k
* The beginIndex to set. bQV("~#
*/
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publicvoid setBeginIndex(int beginIndex){ 1gk0l'.z
this.beginIndex = beginIndex; x
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} N6BNzN}-P
,5:![
/** L6 kZ2-6
* @return ;%!tf{Si
* Returns the currentPage. bN!u}DnN
*/ p_gA/. v=
publicint getCurrentPage(){ PS/W
h
return currentPage; /pU|ZA.z'2
} i\vpGlx
Z?C4a}
/** w Oj88J)
* @param currentPage >\&= [C
* The currentPage to set. NkoofhZ
*/ W/a,.M
publicvoid setCurrentPage(int currentPage){ 7y>(H<^>
this.currentPage = currentPage; :r-.r"[m-
} H}a)^90_
)Oo2<:"
/** D2Vv\f
* @return pd7O`.3
* Returns the everyPage. t#{x?cF
*/ *{Yi}d@h(
publicint getEveryPage(){ R@OSqEnr
return everyPage; qkiJH T
} k_BSY=$e*D
3Mxz_~
/** q>P[n z%
* @param everyPage S_j1=6#^
* The everyPage to set. IY03"
*/ 9D%qXU
publicvoid setEveryPage(int everyPage){ q$|0)}
this.everyPage = everyPage; bu_/R~&3{
} YV4
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MN\i-vAL8
/** _Ws#UL+Nq
* @return 4 *H(sq
* Returns the hasNextPage. tr5'dX4]
*/ +*: }p
publicboolean getHasNextPage(){ S;>4i!Mb
^
return hasNextPage; C)U #T)
} A3<^ U
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/** =>e?l8`%
* @param hasNextPage 'Z59<Y a&x
* The hasNextPage to set. f>O54T .L.
*/ -ywX5B
publicvoid setHasNextPage(boolean hasNextPage){ "2%y~jrDN
this.hasNextPage = hasNextPage; T^d#hl.U
} 2'|XtSj
F68},N>vr@
/** wG;}TxrLS
* @return :ao^/&HZ
* Returns the hasPrePage. 5"$e=y/
*/ %-\FVKX
publicboolean getHasPrePage(){ Y'2-yB
return hasPrePage; loR,XW7z
} )CFk`57U
+jv}\Jt
/** G2=F8kL
* @param hasPrePage D8gQRQ
* The hasPrePage to set. 3,%nkW
*/ 9)jo7,VM
publicvoid setHasPrePage(boolean hasPrePage){ @>+^W&
this.hasPrePage = hasPrePage; .zQ4/
} YfV"_G.ad|
=jsx(3V
/** ZUv
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* @return Returns the totalPage. =kwb`
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* 7Y%!,ff
*/ 3L?WTS6(u
publicint getTotalPage(){ H U:1f)aa
return totalPage; '_k >*trV
} ful]OLV+
hcd!A5
/** BvSdp6z9Iv
* @param totalPage \)uy"+ Z`
* The totalPage to set. 7E;>E9 '
*/ RA#\x.
publicvoid setTotalPage(int totalPage){ {bW"~_6}
this.totalPage = totalPage; qw6EP C
} UIO6|*ka
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} .L~f Fns/
n'! -Pv
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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 'Na|#tPYI
}P05eI
个PageUtil,负责对Page对象进行构造: s.<olxXRW
java代码: I/u'bDq
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/*Created on 2005-4-14*/ qPp1:a"
package org.flyware.util.page; H?rSP0.
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import org.apache.commons.logging.Log; cjCE3V9X
import org.apache.commons.logging.LogFactory; zG&WWc`K
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/** QWU5-p9e8
* @author Joa _K
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* $ijx#a&O
*/ ;:v]NZtc
publicclass PageUtil { Na~g*)uT$
}~7H2d);-
privatestaticfinal Log logger = LogFactory.getLog R
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(PageUtil.class); ~,(0h:8
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/** SIKk|I)
* Use the origin page to create a new page d)`nxnbMeM
* @param page \9dz&H
* @param totalRecords trID#DT~
* @return % <8K^|w
*/ ^hQ:A4@q
publicstatic Page createPage(Page page, int s4\SX,
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totalRecords){ wxdh?sQ
return createPage(page.getEveryPage(), ,apd3X%g
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page.getCurrentPage(), totalRecords); zv$=*
} $#6Fnhh}
/ig^7+#
/** u!=]zW%
* the basic page utils not including exception >=.ch5h3J)
?K= gg<
handler GM34-GH+
* @param everyPage Vvxc8v:
* @param currentPage O+CF/ipX/
* @param totalRecords 34&u]4=L)
* @return page z6GL,wo#
*/ cP}5}+
publicstatic Page createPage(int everyPage, int {|8:U}<#h
5Ws:Ei{R
currentPage, int totalRecords){ 842Mydom
everyPage = getEveryPage(everyPage); E9~&f^f
currentPage = getCurrentPage(currentPage); {Sd@u$&
int beginIndex = getBeginIndex(everyPage, mSVX4XW<
`<]P"G
currentPage); DzX6U[=
int totalPage = getTotalPage(everyPage, v.~Nv@+kR
jgZX~D
totalRecords); I1eb31<
boolean hasNextPage = hasNextPage(currentPage, hr/xpQW
mI_ 6f~
totalPage); ;ph+ZV
boolean hasPrePage = hasPrePage(currentPage); +iZ@.LI
`Z;B^Y0
returnnew Page(hasPrePage, hasNextPage, ,d/CU
everyPage, totalPage, 8EW`*+%=
currentPage, B=o#LL
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beginIndex); $=;bccIob
} ijR-?nrR
ss|6_H =
privatestaticint getEveryPage(int everyPage){ f4@#pnJ3po
return everyPage == 0 ? 10 : everyPage; RPScP
} #/&q
)VSGqYr#
privatestaticint getCurrentPage(int currentPage){ }[hDg6i
return currentPage == 0 ? 1 : currentPage; r&j+; JM5
} iG;d0>Sp
9I^H)~S
privatestaticint getBeginIndex(int everyPage, int qqO10~Xc
8&`T<ECq>
currentPage){ v]d?6g
return(currentPage - 1) * everyPage; I%VV4,I&pK
} b{yH4)O
p!rGPyGC
privatestaticint getTotalPage(int everyPage, int >E2WZHzd2
Hsux>+Q
totalRecords){ 0X}w[^f
int totalPage = 0; 2yVGEp^
| eVTxeq
if(totalRecords % everyPage == 0) ;r2b@x:<_
totalPage = totalRecords / everyPage; FHnHhB [
else SbQ{ >
totalPage = totalRecords / everyPage + 1 ; 5u=U--
1nX68fS.9
return totalPage; SquqaX+<
} Z)Xq!]~/g
pqNoL*
H
privatestaticboolean hasPrePage(int currentPage){ Di5Op(S((
return currentPage == 1 ? false : true; 37<GG)
} /fcwz5~
#!F8n` C-
privatestaticboolean hasNextPage(int currentPage, s3fGX|;
@%5F^Vbd
int totalPage){ @)M.u3{\
return currentPage == totalPage || totalPage == )9;kzp/
X~/9Vd g
0 ? false : true; YRT}fd>R&
} sjVl/t`l
07HX5 Hd
aV0;WH_3
} v2dSC(hRZ
H603L|4
Q=9VuTE
EzY
scX.[
E rRMiT
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 ;tIIEc
0$dY;,Q .
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 :Q%yW%St$
)="g?E3
做法如下: gs2&0rnOy\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 &`9bGO
C J}4V!;|
的信息,和一个结果集List: nh_xbo5L[
java代码: 70 DQ/b
j(2tbWg9-
oU{-B$w
/*Created on 2005-6-13*/ L:]; [xa%
package com.adt.bo; hF?\K^tF
e1Z;\U$&.
import java.util.List; ZBh@%A
'XjHB!!hU
import org.flyware.util.page.Page; J1wGK|F~
%>QSeX
/** e[Ul"pMvS`
* @author Joa r|sy_Sk/{
*/ U S~JLJI
publicclass Result { A UO0
9cHNwgD>v
private Page page; Y{\2wU!Isn
s?gXp{O?X
private List content; +r34\mAO
i_Q4bhVj
/** r'}k`A5>
* The default constructor @eD2<e
*/ YJ;a{)e
public Result(){ ;R-Q,aCM}
super(); u=?P*Y/|W
} X$Qi[=L
vzQmijr-
/** Lw78v@dY
* The constructor using fields vskM;
* 'Y/V9;`)s
* @param page O"w_sw
* @param content MDXQj5s^
*/ ` G/QJH{I
public Result(Page page, List content){ NhaeAD
$e
this.page = page; ]4pC\0c
this.content = content; Y K 62#;
} kKTED1MW&W
;?[ +vf")
/** ^*T{-U'
* @return Returns the content. B=qRZA!DQ?
*/ AFnlt
publicList getContent(){ REe%>|
return content; @ F"ShT0
} (%^TTe
zj0pP{y
/** ?>Ci`XlLr
* @return Returns the page. w2_I/s6B
*/ >5Rw~
public Page getPage(){ Bk(XJAjY
return page; dXSb%ho
} 2T?1X{g
Vam8NnZ|r
/** 0Nzv@g{3
* @param content .*..pf|/
* The content to set. k-p7Y@`+a
*/ (3HgI
public void setContent(List content){ +R jD\6bJb
this.content = content; 6O?S r,
} UEb'E;
L
~'N6
/** p~VW3u]
* @param page Q14;G<l-
* The page to set. _p^ "!
*/ w\[*_wQp
publicvoid setPage(Page page){ sJ*U Fm{
this.page = page; vG=$UUh@~
} *`/@[S2,cu
} gG|1$
<\Dl#DH
8c'-eT"
U\plt%2m>
s.Ic3ITd,
2. 编写业务逻辑接口,并实现它(UserManager, 15yV4wHr
|0Ug~jKU
UserManagerImpl) 7o%|R2mL}
java代码: _z6u^#Si
=*G'.D /*
<{~UKi
/*Created on 2005-7-15*/ ;&:Et
package com.adt.service; n/|`Dz.
\{^yB4F_Z
import net.sf.hibernate.HibernateException; ?DTP-#5Ba
h1d0{
import org.flyware.util.page.Page; bao5^t}
Al;oI3
import com.adt.bo.Result; G~j<I/)"
omU)hFvyS
/** 6>^k9cJp
* @author Joa ]qTr4`.
*/ Q ?<9
publicinterface UserManager { !q1^X% a
fu;B ?mIn
public Result listUser(Page page)throws W-B[_
Fi}rv[`XY[
HibernateException; ^d=@RTyo/
Jm^jz
} nf^k3QS\
V'4}9J
0X6o
qOanu
pNsLoNZ3w
java代码: (M?Q9\X
_
q1|\E%`h
\d`Sz
*
/*Created on 2005-7-15*/ =1?yS3
package com.adt.service.impl; '.v^seU
*g}&&$b0
import java.util.List; U~c;W@T
xL"o)]a=
import net.sf.hibernate.HibernateException; nlnJJM&J$
M- A}(r +J
import org.flyware.util.page.Page; !~kzxY
import org.flyware.util.page.PageUtil; $S ("-3
f@g
import com.adt.bo.Result; n#,l&Bx
import com.adt.dao.UserDAO; u{d`
import com.adt.exception.ObjectNotFoundException; SZ){1Hu
import com.adt.service.UserManager; +5\\wGo<
,_-*/- 7;8
/** d8I:F9
* @author Joa bME3" e{O
*/ w#b2iE+Bw
publicclass UserManagerImpl implements UserManager { }e @-[RJ!
nJ@hzK.
private UserDAO userDAO; 9D21e(7X
qa?y lR"kA
/** gWPa8q<b
* @param userDAO The userDAO to set. 2J;CiEB
*/ +.uk#K0o
publicvoid setUserDAO(UserDAO userDAO){ ' 1nU[,Wj
this.userDAO = userDAO; =hlu,
B y
} bS6Yi)p
s]>%_(5
/* (non-Javadoc) TD9`SSpP
* @see com.adt.service.UserManager#listUser M] *pBc(o0
U0T N8O}Z
(org.flyware.util.page.Page) R:p,Hav<q
*/ g{(nt5|^l
public Result listUser(Page page)throws x~^nlnKVf
'& :"/4@)
HibernateException, ObjectNotFoundException { _XPc0r:?>
int totalRecords = userDAO.getUserCount(); u&bU !ZI
if(totalRecords == 0) bc-)y3gHU
throw new ObjectNotFoundException vL0Ol-Vt
:Aw VeX@
("userNotExist"); xb\:H@92
page = PageUtil.createPage(page, totalRecords); EUqG"h5#A{
List users = userDAO.getUserByPage(page); zBfBYhS-
returnnew Result(page, users); [t'"4
} \:7EKzQ
//|Vj | =
} Hq$|j,&?
g7-K62bb
^Quy64M
RJD3o_("K
U4JN,`p{
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 a/fYD2uNo
_{%H*PxTn=
询,接下来编写UserDAO的代码: 8E{>czF"
3. UserDAO 和 UserDAOImpl: PMcyQ2R->
java代码: A\Gw+l<h,
RwWQ$Eb_s
lla96\R
/*Created on 2005-7-15*/ "
cg>g/
package com.adt.dao; <ZEA&:p
jEI L(0_H
import java.util.List; ~O6=dR
Is[0ri
import org.flyware.util.page.Page; ":ycyN@g
79_MP
import net.sf.hibernate.HibernateException; Viw3 /K
Z%R^;8 !~
/** Dl{Pd`D
* @author Joa ,d#4Ib
*/ cALs;)z
publicinterface UserDAO extends BaseDAO { AbB>ZT>hR
+fN0>@s
publicList getUserByName(String name)throws KMZ`Wn=
rf@81Ds
HibernateException; v]~[~\|a
[qB=OxH?
publicint getUserCount()throws HibernateException; @$]h[
S8l+WF4q
publicList getUserByPage(Page page)throws M;R>]wP"V
Tx_LH"8
HibernateException; R0[Gfq9M=
;f
Gi5=-
} bkTj
Q
ojri~erJE?
lRb)Tz6SE
FmPF7
2X`M&)"X
java代码: \z
'noc
yr?\YKV)I
566EMy|
/*Created on 2005-7-15*/ -/X-.#}-
package com.adt.dao.impl; 2ip~qZNw><
*O~D lf
import java.util.List; G`jhzG
i{2KMa{K
import org.flyware.util.page.Page; P;34Rd
YQ/*|
import net.sf.hibernate.HibernateException; z5I<,[`
import net.sf.hibernate.Query; _PF><ODX2
q2y:bqLWl
import com.adt.dao.UserDAO; @p;4g_F
Dts:$PlCk
/** uw]Jm"=w
* @author Joa ryN-d%t?
*/ |dK-r
public class UserDAOImpl extends BaseDAOHibernateImpl /+u*9ZR&1
9YKEME+:
implements UserDAO { y3#\mBiw
4/b#$o<I?
/* (non-Javadoc) f[w$3
* @see com.adt.dao.UserDAO#getUserByName y4') !e
IWkBq]Y
(java.lang.String) })B)-8
*/ ^:BRbp37i
publicList getUserByName(String name)throws \MU4"sXw
PA E)3
HibernateException { r"+
WUU
String querySentence = "FROM user in class dn Xc- <
+] #>6/2q
com.adt.po.User WHERE user.name=:name"; V4 7Fp
Query query = getSession().createQuery /bWV`*
X^ovP'c2
(querySentence); VaB7)r
query.setParameter("name", name); 0pQ>V)
return query.list(); 5Ai
Yx}
} IH5thL@D
sb1/4u/W
/* (non-Javadoc) wgrYZ^]
* @see com.adt.dao.UserDAO#getUserCount() MmX42;Pw
*/ U+KbvkX wj
publicint getUserCount()throws HibernateException { ~'ovJ46tx
int count = 0; XP'KgTF
String querySentence = "SELECT count(*) FROM ]n+:lsiV
UJb7v:^
user in class com.adt.po.User"; *G9;d0
Query query = getSession().createQuery (/%}a`2#o
G 6][@q
(querySentence); z#y<QH
count = ((Integer)query.iterate().next -I -wdyDr
-$7Jc=:>
()).intValue(); /<mc~S7
return count; \sk,3b-&'
} [-l^,,E
Uc4r
/* (non-Javadoc) J(Bn
n
* @see com.adt.dao.UserDAO#getUserByPage X**wRF
R{T4AZ@,'
(org.flyware.util.page.Page) bHp|>g
*/ t[<=QK
publicList getUserByPage(Page page)throws oR+Fn}mG
txi
m|)
HibernateException { :A[ Gtc(_
String querySentence = "FROM user in class (nBsf1l
zmdOL9"a
com.adt.po.User"; .8"o&%$`V
Query query = getSession().createQuery {S|uQgs6j
2uB.0
(querySentence); `p!.K9r7
query.setFirstResult(page.getBeginIndex()) 4o%hH
.setMaxResults(page.getEveryPage()); toF@@%
return query.list(); {vaq,2_w
} 69_c,(M0
-/h$Yb
} , 7}Ri
4F'@yi^Gt
>6@UjGj54
b&LhydaJ
=/zQJzN
至此,一个完整的分页程序完成。前台的只需要调用 R)#"Ab Z'
_8bqk\m+
userManager.listUser(page)即可得到一个Page对象和结果集对象 P?bdjU#_n`
`aCcTs7~]p
的综合体,而传入的参数page对象则可以由前台传入,如果用 Q[}mH: w
=14p Ee
webwork,甚至可以直接在配置文件中指定。 =~R0U
oL<^m?-u
下面给出一个webwork调用示例: &R 0BuFL8
java代码: QII>XJ9
5bgx;z9
l!`m}$
/*Created on 2005-6-17*/ c0tv!PSw
package com.adt.action.user; uz%rWN`{
&)rmv
import java.util.List; 3 iY`kf
Z!*Wn`d-k
import org.apache.commons.logging.Log; W{k}ogI;
import org.apache.commons.logging.LogFactory; ^D!UF(H
import org.flyware.util.page.Page; akaQ6DIdG
\;Ii(3+v;
import com.adt.bo.Result; J&lQ,T!?B
import com.adt.service.UserService; T'w=v-(J
import com.opensymphony.xwork.Action; oqG
0 @@
<}|+2f233+
/** u\6:Txqq
* @author Joa UA{A G;
*/ &Uzg&eB
publicclass ListUser implementsAction{ A H`6)v<f
uYV#'%
privatestaticfinal Log logger = LogFactory.getLog ).k=[@@V
p`Ax)L\f
(ListUser.class); `2GHB@S"k
2 &R-zG
private UserService userService; ;hRo}
+\l
;X\,-pjv
private Page page; SC'fT!
1;SWfKU?.
privateList users; c\n\gQ:LQ
`2{x8A
/* qRTy}FU1
* (non-Javadoc) uQrD}%GI
* B1 'Ds
* @see com.opensymphony.xwork.Action#execute() &g|-3)A
*/ {D$#m
publicString execute()throwsException{ o4tQ9X=}
Result result = userService.listUser(page); eqYa`h@g^
page = result.getPage(); fAYm3+.l3
users = result.getContent(); XD9lox
return SUCCESS; )fv0H&g
} l\a 0 k4
2}t2k>
/** TN(1oJ:
* @return Returns the page. W,}C*8{+
*/ wQDKv'zU1
public Page getPage(){ 1)H+iN|im/
return page; {i3]3V"Xp
} `5Q0U%`W
{Dqf.w>t
/** ~`(#sjr6KR
* @return Returns the users. d XrLeoK
*/ "\Z.YZUa\
publicList getUsers(){ o[0Cv*
return users; E\ 5t&jZr
} !Mceg
fC52nK&T8
/** 3
rV)JA
* @param page #D&eov?
* The page to set. =rGjOb3+
*/ vEk
jd#
publicvoid setPage(Page page){ g&) XaF[!
this.page = page; *?+E?AGe
} V!(Ty%7
<Zl}u:(w
/** pq*W;6(-
* @param users H9F\<5n]-l
* The users to set. ymiOtA Z
*/ ESft:3xyw
publicvoid setUsers(List users){ ]:8:|*w
this.users = users; txw:m*(%
} 4DaLmQ2O
9])dLL0
/** V)=!pT
* @param userService *xI0hFJIM
* The userService to set. GMyzQ]@}
*/ n3-5`Jti
publicvoid setUserService(UserService userService){ p<: bPw
this.userService = userService; Gk
g)\ 3
} N*gnwrP{
} )OS^tG[=
4[v
%]g`
IZoS2^:yw
HM/2/
/
DKp+ nq$
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, >hQeu1 ~W
S=@.<gS
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 y yW;VKN
Y/?V%X
么只需要: }4b
4<Sm_h
java代码: jhOQ)QE|
5ro^<P0f**
|
U )
<?xml version="1.0"?> 3A!`U6C(
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork YzNSZJPD
p"\Z@c
1.0//EN" "http://www.opensymphony.com/xwork/xwork- JTA65T{3
t2uX+1F
1.0.dtd"> c@>Tzk%?"
V{+'(<SV
<xwork> pyJY]"UHVE
8lk@ev=O&
<package name="user" extends="webwork- uxLT*,
#eadkj#;
interceptors"> ""q76cx
WdI9))J2S
<!-- The default interceptor stack name yyB;'4Af
\"Jgs.
--> "H\1Z,P<m
<default-interceptor-ref %/iD@2r
ova4
name="myDefaultWebStack"/> cBZ$$$v\#
"NWILZwEV
<action name="listUser" d5jZ?
*oZ]k`-!8
class="com.adt.action.user.ListUser"> .^
djt
<param +?y ', Ir
= Lt)15
name="page.everyPage">10</param> RC?gozBFJ
<result >%LZ|*U
AQ+MjS,
name="success">/user/user_list.jsp</result> ynY(
</action> wr>[Eo@%\
AH-B/c5
</package> S\5%nz\
~;$,h ET
</xwork> 1seWR"
GYH{_Fq
+)$oy]
&Z'3n9zl
~(aMKB
~i_YrTp
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 @%iZT4`Ejf
69< <pm,m
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。 O?,Grn%'.
Pa)'xfQ$Y6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 M18> %zM
-J &y]'
Z:eB9R#2y
|xYr0C[Pq
'aV])(Wm>
我写的一个用于分页的类,用了泛型了,hoho *'&]DJj
oD<aWZ"Z
java代码: "qh~wK J
{0L.,T~g+[
U/ds(*g@
package com.intokr.util; gug9cmA/Q7
_ \&vA5-
import java.util.List; Mbm'cM&}
!#&`1cYX
/** xu%_Zt2/?j
* 用于分页的类<br> J(>T&G;
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pSa
pF)1>
* A4{14Y;?
* @version 0.01 [/=Z2mtA
* @author cheng Yw(O}U 5e
*/ _p*a`,tK
public class Paginator<E> { Dc@OrQu
privateint count = 0; // 总记录数 l6_dVK;s
privateint p = 1; // 页编号 iHa:6
privateint num = 20; // 每页的记录数 wE~&Y?^
privateList<E> results = null; // 结果 CH9Psr78
x3AAn,m8
/** CKE):kHu
* 结果总数 MD9 8N{+[|
*/ @bRKJPU9)
publicint getCount(){ e@h(Zwp
return count; h-.xx4D
}
^t}1$H
Lm&BT)*
publicvoid setCount(int count){ l4bLN
this.count = count; Y~TD)c=
} '2z1$zst,#
^V}c8 P|
/** ]A=yj@o$xN
* 本结果所在的页码,从1开始 8 /vGA=
* *Z8qd{.$q
* @return Returns the pageNo. Uee(1
*/ f/95}6M
publicint getP(){ N
T>[
2<
return p; 3p1U,B}
} kk>z,A4
h_
*$]50 \W
/** 2WK c;?
* if(p<=0) p=1 +R8G*2
* oNhCa>)/
* @param p ^>/~MCyM.
*/ XjXz#0nR
publicvoid setP(int p){ b|-}?@&7&q
if(p <= 0) i&TWIl8
p = 1; cY^'Cj
this.p = p; b($9gre>mI
} QQ,V35Vp[
+mPVI
/** 5pU/X.lc
* 每页记录数量 6e>P!bo
*/ _]v@Dq VP
publicint getNum(){ @+{F\SD\
return num; oTJ^WePZQ
} "c.@4#/_
0Ke2%+yqJ
/** +!Q*ie+q
* if(num<1) num=1 _v[gJ(F
*/ <2af&-EGs
publicvoid setNum(int num){
7NvnCs
if(num < 1) 3a?|}zr4
num = 1;
od)ssL&E~
this.num = num; 8 =oUE$9
} 0qq>(K[
ZaYUf
/** Mt4*`CxtH;
* 获得总页数 :b0|v`FU
*/ .?`8B9w
publicint getPageNum(){ m[CyvcF*u
return(count - 1) / num + 1; B.C:06E5
} d#HlO}
x1h&`QUP
/** R`J.vMT
* 获得本页的开始编号,为 (p-1)*num+1 IISdC(5
*/ Ft^X[5G4L
publicint getStart(){ Jcy+(7lE)
return(p - 1) * num + 1; p9 G{Q
} /|8rVYSs
a/</P
|UG
/** xO^lE@a o
* @return Returns the results. }_BNi;H
*/ nAC>']K4$
publicList<E> getResults(){ mp)+wZAN&
return results; 388vdF
} AJ3%Z$JJ;s
6zi 5#23
public void setResults(List<E> results){ y=0)vi{]
this.results = results; d}y")q|F
} nYR#Q|
G8zbb
public String toString(){ 7p-
RPC
StringBuilder buff = new StringBuilder -'F27])
xI_0`@do
(); 0NK|3]p
buff.append("{"); ~Ajst!Y7=
buff.append("count:").append(count); 3Vbt(K
buff.append(",p:").append(p); h=qT@)h1>
buff.append(",nump:").append(num); u* G+=aV.6
buff.append(",results:").append FJ{/EloF
&2Ef:RZF
(results); wPX^P
buff.append("}"); O^PN{u
return buff.toString(); _e/Bg~
} {1_<\~J
Xr:s-L
} :dQRrmM
P4zwTEk`
^f57qc3nF