Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ^L-w(r62<
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 $S=~YzO
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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 p;u 1{
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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 +fd@K
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。
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分页支持类: qQxA@kdd
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java代码: 7{An@hNh
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package com.javaeye.common.util; .-KtB(t
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import java.util.List; 8L-4}!~C
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publicclass PaginationSupport { `e $n$Bh
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publicfinalstaticint PAGESIZE = 30; 45+%K@@x
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privateint pageSize = PAGESIZE; \/*Nf?;
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privateList items; _}e7L7B7g
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privateint totalCount; Z6^QB@moj
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privateint[] indexes = newint[0]; 9:%n=U Rd
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privateint startIndex = 0; BeI;#m0
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public PaginationSupport(List items, int ss`P QN
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totalCount){ /BMtcCPG!
setPageSize(PAGESIZE); ms}f>f=
setTotalCount(totalCount); @GG(7r\/B
setItems(items); V \6(d
setStartIndex(0); <8rgtu!VU
} G`,u40a
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public PaginationSupport(List items, int ok `]:gf
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totalCount, int startIndex){ !8Z2X!$m{<
setPageSize(PAGESIZE); }3f
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setTotalCount(totalCount); hhpv\1h#
setItems(items); G [3k
setStartIndex(startIndex); 6x_T@
} 8M^wuRn
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public PaginationSupport(List items, int #M5_em4kN
i s L{9^
totalCount, int pageSize, int startIndex){ {)V? R
setPageSize(pageSize); >*dQqJI
setTotalCount(totalCount); kDzj%sm!
setItems(items); *me,(C
setStartIndex(startIndex); WY+(]Wkao
} LY-lTr@A^
}iilzE4oH#
publicList getItems(){ 9<|m4
return items; U_}7d"<| ?
} B(j02<-
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publicvoid setItems(List items){ ch@x]@-;A3
this.items = items; |JUe>E*
} tu\mFHvlg
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publicint getPageSize(){ ~ww?Emrw
return pageSize; $ph0ag+
} [kbC'Eh*
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publicvoid setPageSize(int pageSize){ gbm0H-A:*
this.pageSize = pageSize; }B y)y;~
} Y4mC_4EU
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publicint getTotalCount(){ fO].e"}
return totalCount; 8>UKIdp
} Fr-[UZ~V
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publicvoid setTotalCount(int totalCount){ M
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if(totalCount > 0){ k$C"xg2
this.totalCount = totalCount; - $U@By<SJ
int count = totalCount / u]HS(B,ht
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pageSize; W*k`
if(totalCount % pageSize > 0) Ko#4z%Yq
count++; z!fdx|PUX
indexes = newint[count]; u(W^Nou/+
for(int i = 0; i < count; i++){ YgCc|W3{
indexes = pageSize * $v]T8|h
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i; v btAq^1
} VS?dvZ1cC
}else{ P:
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this.totalCount = 0; U.: sK*
} A j,]n>{
} ],n%Xp
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publicint[] getIndexes(){ 0pD
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return indexes; +%P t_
} Vo%Yf9C
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publicvoid setIndexes(int[] indexes){ kLJlS,nh\r
this.indexes = indexes; wG+=}1X
} TMK'(6dH
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publicint getStartIndex(){ =f>HiF
return startIndex; n!a<:]b<
} E*BSfn&i
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publicvoid setStartIndex(int startIndex){ [FGgkd}
if(totalCount <= 0) Y;} 2'"
this.startIndex = 0; yz?q(]
elseif(startIndex >= totalCount) @rF/]UJ
this.startIndex = indexes 1!!\+
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[indexes.length - 1]; Ls]@icH0
elseif(startIndex < 0) r*chL&7
this.startIndex = 0; >9=:sSQu
else{ G]4OFz+
this.startIndex = indexes ,+s e
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[startIndex / pageSize]; r@iASITX
} u)v$JpNE
} &pM'$}T*
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publicint getNextIndex(){ %swR:Bv
int nextIndex = getStartIndex() + <s_=-"
il
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pageSize; H'EY)s Hi
if(nextIndex >= totalCount) ZRnL_z~
return getStartIndex(); w:}C8WKw
else 3qtr9NI
return nextIndex; vf<UBa;Xm
} Gg|M+M?+
~Q?!W0ZBE
publicint getPreviousIndex(){ CZY7S*fL
int previousIndex = getStartIndex() - n+HsQ]z.
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pageSize; X8b|]Nr
if(previousIndex < 0) [SkKz>rC
return0; qgx?"$ Z
else :6Pnie
return previousIndex; >Q=Ukn;k
} W5.Va.
dAL3. %
} ! RPb|1Y}+
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抽象业务类 DL {R|3{N
java代码: Bd5+/G=m
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/** -f9]v9|l
* Created on 2005-7-12 *"cD.)]#2
*/ XK qK<!F
package com.javaeye.common.business; MS*G-C
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import java.io.Serializable; rA1qSG~c
import java.util.List; rQJ"&CapT
K"\MU
import org.hibernate.Criteria; 6):Xzx,
import org.hibernate.HibernateException; wzh]97b
import org.hibernate.Session; GX?*1
import org.hibernate.criterion.DetachedCriteria; Km!nM$=k
import org.hibernate.criterion.Projections; J -V49X#
import "'a* [%
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org.springframework.orm.hibernate3.HibernateCallback; ka/XK[/'
import 02\JzBU
Gr: 3{o`
org.springframework.orm.hibernate3.support.HibernateDaoS !8R@@,_v
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upport; *5OCqU+g
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import com.javaeye.common.util.PaginationSupport; +@<KC
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public abstract class AbstractManager extends ghAi{@s$)
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HibernateDaoSupport { tHh HrMxO
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privateboolean cacheQueries = false; zN~6HZ_:^
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privateString queryCacheRegion; d-B7["z,
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publicvoid setCacheQueries(boolean R-rCh.
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cacheQueries){ G[h(xp?,l
this.cacheQueries = cacheQueries; A&,,9G<
} ]|U-y645
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publicvoid setQueryCacheRegion(String {v` 2sB
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queryCacheRegion){ p'f%%#I
this.queryCacheRegion = % /}WUP^H
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queryCacheRegion; LA%bq_>f
} VK:8 Nk_y
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publicvoid save(finalObject entity){ 1J}8sG2`
getHibernateTemplate().save(entity); QI}E4-s8
} U#
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publicvoid persist(finalObject entity){ 2i7e#
getHibernateTemplate().save(entity); G7@O`N8'
} &:5\"b
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publicvoid update(finalObject entity){ rwE%G>Vb
getHibernateTemplate().update(entity); =IjQ4 0W
} z@Hp,|Vy[
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publicvoid delete(finalObject entity){ j_cs;G: "
getHibernateTemplate().delete(entity); U@F)2?
} "TS
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publicObject load(finalClass entity, +jP~s
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finalSerializable id){ 'ZP)cI:+X
return getHibernateTemplate().load YB,t0%vTJw
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(entity, id); o)Z=m:t,lK
} r0]4=6U
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publicObject get(finalClass entity, }{[mrG
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finalSerializable id){ n_u1&a'
return getHibernateTemplate().get 6oD\-H
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(entity, id); ihCIh6
} !CUoHTmB
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publicList findAll(finalClass entity){ nV_8Ke
return getHibernateTemplate().find("from d3;qsUh$yv
V5`^Y=X(%
" + entity.getName()); &M/>tEZ)
} I+(/TP
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publicList findByNamedQuery(finalString eH%RNtP`
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namedQuery){ qMYe{{r
return getHibernateTemplate 8,"yNq
Q{g;J`Z)p
().findByNamedQuery(namedQuery); Tr&M~Lgb)
} 2aN<w'pA
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publicList findByNamedQuery(finalString query, I=DxRgt
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finalObject parameter){ g'$tj&Vk:
return getHibernateTemplate bGF7Zh9
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().findByNamedQuery(query, parameter); `D$Jv N
} 9W ^xlid6
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publicList findByNamedQuery(finalString query, O1&b]C#
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finalObject[] parameters){ p[AO'
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return getHibernateTemplate eLD|A=X?
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().findByNamedQuery(query, parameters); .Dg*\ h
} GB7/x*u
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publicList find(finalString query){ cD|Htt"
return getHibernateTemplate().find M<PIeKIEB
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(query); =ONHKF[UJ
} ^5GW$
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publicList find(finalString query, finalObject mEyK1h1G@
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parameter){ ikD1N
return getHibernateTemplate().find 8T)&`dM6P~
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(query, parameter); u+H;
@
} !TM*o+;
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public PaginationSupport findPageByCriteria B~
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(final DetachedCriteria detachedCriteria){ 'G\XXf%J
return findPageByCriteria ^~`?>}MJ
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); wr(*?p]R
} =Z=o#46JY
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public PaginationSupport findPageByCriteria BVsD(
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(final DetachedCriteria detachedCriteria, finalint 0+Ta%H{
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startIndex){ tVrY3)c
return findPageByCriteria YOr:sb
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(detachedCriteria, PaginationSupport.PAGESIZE, >MK>gLg}!
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startIndex); k3?rp`V1
} mE`kjmX{ E
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public PaginationSupport findPageByCriteria ML;*e "$
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(final DetachedCriteria detachedCriteria, finalint tE6!+c<7
i)
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pageSize, )^||\G
finalint startIndex){ wNFz*|n
return(PaginationSupport) H{J'#
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getHibernateTemplate().execute(new HibernateCallback(){ GdV1^`M6
publicObject doInHibernate ~Tbj=f
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(Session session)throws HibernateException { (C4fG@n
Criteria criteria = 8
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detachedCriteria.getExecutableCriteria(session); vAY,E=&XvM
int totalCount = Y!iZW
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((Integer) criteria.setProjection(Projections.rowCount }_=eT]
su*Pk|6%
()).uniqueResult()).intValue(); m]i @ +C
criteria.setProjection kmzH'wktt
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(null); DCqY|4Qc
List items = .ERO|$fv
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criteria.setFirstResult(startIndex).setMaxResults f&v9Q97=
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(pageSize).list(); ctE\ q
PaginationSupport ps = uqz]J$
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new PaginationSupport(items, totalCount, pageSize, X7k.zlH7T
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startIndex); N?Lb
return ps; >pUtwIP
} BIuK @$
}, true); \%UkSO\nO3
} V#VN%{
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public List findAllByCriteria(final )K &(
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DetachedCriteria detachedCriteria){ KYzv$oK
return(List) getHibernateTemplate F:x [
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().execute(new HibernateCallback(){ z5ij(RE]
publicObject doInHibernate H":oNpfb
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(Session session)throws HibernateException { 4apL4E"r
Criteria criteria = vpmj||\-
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detachedCriteria.getExecutableCriteria(session); MEB it
return criteria.list(); RX/hz|
} vWAL^?HUP
}, true); I`NjqyTW
} #g6.Glz3
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public int getCountByCriteria(final N-lkYL-%\j
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DetachedCriteria detachedCriteria){ j?'GZ d"B
Integer count = (Integer) .W js~0c
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getHibernateTemplate().execute(new HibernateCallback(){ !47n[Zs
publicObject doInHibernate <[w=TdCPs
#%DE;
(Session session)throws HibernateException { -Uml_/rd_
Criteria criteria = *}P~P$q%
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detachedCriteria.getExecutableCriteria(session); ;*MLRXq
return 21"1NJzP
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criteria.setProjection(Projections.rowCount %c4Hse#Y
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()).uniqueResult(); Kr)a2rZ}SL
} 1I:+MBGin
}, true); O%bEB g
return count.intValue(); ](hE^\SC
} EFz&N\2
} 4EY)!?;
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用户在web层构造查询条件detachedCriteria,和可选的 <Y}R#o1Z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 1y}Y9mlD.
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PaginationSupport的实例ps。 z4N*b"QF
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ps.getItems()得到已分页好的结果集 q@{Bt{$x
ps.getIndexes()得到分页索引的数组 GWfL
ps.getTotalCount()得到总结果数 $&=S#_HQS
ps.getStartIndex()当前分页索引 LGn:c;
ps.getNextIndex()下一页索引 n@)K #
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :.Wr{"`
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 yK=cZw%D
.6Pw|xu`Pw
一下代码重构了。 5?x>9Ca
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我把原本我的做法也提供出来供大家讨论吧: r 8RoE`/T
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首先,为了实现分页查询,我封装了一个Page类: %$.3V#?
java代码: K|[*t~59
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/*Created on 2005-4-14*/ %#kg#@z_`e
package org.flyware.util.page; %lGl,me H
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/** HMNLa*CL'
* @author Joa 2fL;-\!y(
* H*PSR
*/ eceP0x
publicclass Page { fumm<:<CLO
50S&m+4d+
/** imply if the page has previous page */ _z|65H
privateboolean hasPrePage; C&(N
I
Tw-;7Ae
/** imply if the page has next page */ ``hf=`We
privateboolean hasNextPage; gtppv6<Mj4
D9H?:pmv?
/** the number of every page */ asppRL||
privateint everyPage; 8.O8No:'&
I=`U7Bis"
/** the total page number */ V@g'#={r
privateint totalPage; ;~m8;8)
uxr #QA
/** the number of current page */ S4_YT@VD%
privateint currentPage; a.k.n<
0Qf,@^zL*
/** the begin index of the records by the current },{$*f[
rX2.i7i,
query */ yPb" V
privateint beginIndex; !$gR{XH$]
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/** The default constructor */ Pd_U7&w,5
public Page(){ 9y"@(
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} p8Qk'F=h
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/** construct the page by everyPage '-Vt|O_Q
* @param everyPage I 5^!y
* */ I;wp':
public Page(int everyPage){ | ATvS2
this.everyPage = everyPage; -cAo@}v
} _@
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/** The whole constructor */ pmyXLT
public Page(boolean hasPrePage, boolean hasNextPage, 2K/4Rf0;
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int everyPage, int totalPage, #lL^?|M
int currentPage, int beginIndex){ .SU8)T
this.hasPrePage = hasPrePage; ,is3&9
this.hasNextPage = hasNextPage; rZ}:Z'`
this.everyPage = everyPage; X^wt3<Kbf
this.totalPage = totalPage; 2} /aFR
this.currentPage = currentPage; a%JuC2
this.beginIndex = beginIndex; f<d`B]$(
} s<<ooycBrQ
];[}:f
/** dO!
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* @return ^BikV
* Returns the beginIndex. *av<E
*/ E Nhl&J
publicint getBeginIndex(){ Q{>+ft U
return beginIndex; <lPm1/8
} \wz6~5R
l<58A7
/** he;dq)-e9
* @param beginIndex `EA\u]PwQ
* The beginIndex to set. 61C7.EZZ;
*/ Bu~]ey1
publicvoid setBeginIndex(int beginIndex){ P~ >OS5^
this.beginIndex = beginIndex; "c%0P"u
} =(j1rW!
|6sp/38#p
/** _)3|f<E_t)
* @return :^6y7&o[
* Returns the currentPage. Qb-M6ihcc
*/ ;"5&b!=t
publicint getCurrentPage(){ l*(8i ^
return currentPage; K_|k3^xx"
} NX*Q F+
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/** ZB=
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* @param currentPage [Kg+^N%+
* The currentPage to set. u&Yz[)+b=g
*/ qd ~BnR$=
publicvoid setCurrentPage(int currentPage){ ;#W2|'HD
this.currentPage = currentPage; -">;-3,K
} u5`u>.!
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/** oM>l#><nq
* @return ~D j8z+^
* Returns the everyPage. oGnSPI5KGC
*/ we//|fA<
publicint getEveryPage(){ cJ=6r
:
return everyPage; )0]'QLH
} M6"PX *K
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/** i
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* @param everyPage iy.p n
* The everyPage to set. G"qvz{*
*/ {L{o]Ii?g
publicvoid setEveryPage(int everyPage){ _}Ac n$
this.everyPage = everyPage; HmGWht6R
} oq
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/** EH J.T~X
* @return ( Y[Q,
* Returns the hasNextPage. :D5Rlfj
*/ L\J;J%fz.
publicboolean getHasNextPage(){ b|:YIXml
return hasNextPage; ~g]Vw4pv
} I3L<[-ZE
zj{pJOM06
/** gD@){Ip
* @param hasNextPage lgL%u K)
* The hasNextPage to set. BA:VPTZq
*/ e8a+2.!&\
publicvoid setHasNextPage(boolean hasNextPage){ Hk3sI-XkA
this.hasNextPage = hasNextPage; Woym/[i
} I^-Sb=j?Z
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/** WaRw05r
* @return 03X1d-
* Returns the hasPrePage. Jq-]7N%k/
*/ 7;(`MIFXs
publicboolean getHasPrePage(){ ^}=,g
return hasPrePage; ~Fcm[eoC
} !c
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/** q6luUx,@m
* @param hasPrePage _1\v
* The hasPrePage to set. _
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*/ D#C~pdp
publicvoid setHasPrePage(boolean hasPrePage){ 7&)bJ@1U
this.hasPrePage = hasPrePage; eu-*?]&Di
} [q[Y~1o/&H
P/eeC"
/** }j)e6>K])
* @return Returns the totalPage. 97*p+T<yp
* &DX! f
*/ ~TD0zAA&
publicint getTotalPage(){ <)H9V-5aZ
return totalPage; .uZ3odMlx
} oJz^|dW
?);v`]
/** O,f?YJ9S
* @param totalPage <iC(`J$D
* The totalPage to set. Wqw1J=]
*/ =8.
,43+
publicvoid setTotalPage(int totalPage){ X&`t{Id?6
this.totalPage = totalPage; )7Wf@@R'F
} 6A-|[(NS
/W<;Z;zk
} X.{S*E:$u
\ ~$#1D1f
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 ^hM4j{|&M
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个PageUtil,负责对Page对象进行构造: ;4|15S
java代码: <\^8fn
}Zn}
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/*Created on 2005-4-14*/ sDlO#
package org.flyware.util.page; aEeodA<(
Z@!+v19^
import org.apache.commons.logging.Log; mz0X3
import org.apache.commons.logging.LogFactory; /nA{#HY
YN F k
/** <PH#[dH
* @author Joa htF] W|z
* `M8i92V\qY
*/ ^u ~Q/4
publicclass PageUtil { "+G8d'%YV
xi}skA
privatestaticfinal Log logger = LogFactory.getLog /y}xX
vA8nvoi
(PageUtil.class); !%c\N8<>GD
)Ql%r?(F+
/** Vt#.eL)Ee
* Use the origin page to create a new page e(t\g^X
* @param page @:#eb1<S
* @param totalRecords p<"m[Dt]
* @return zQd
2
*/ )+DmOsH
publicstatic Page createPage(Page page, int 8{sGNCvU
x7[BK_SY
totalRecords){ #@Jq~$N|
return createPage(page.getEveryPage(), Ad_hKO
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page.getCurrentPage(), totalRecords); zK@@p+n_#.
} H G^'I+Yn
&Z%?!.4j@
/** jNk%OrP]
* the basic page utils not including exception l]8uk^E
0 @oJFJrO
handler 2J BR)P
* @param everyPage 4,DeHJjAlE
* @param currentPage t b}V5VH
* @param totalRecords ( a#BV}=
* @return page &tj!*k'
*/ P&LsVR{#
publicstatic Page createPage(int everyPage, int FQ\h4` >B
/%^#8<=|U
currentPage, int totalRecords){ 3[*}4}k9
everyPage = getEveryPage(everyPage); H4+i.*T#
currentPage = getCurrentPage(currentPage); ep{FpB
int beginIndex = getBeginIndex(everyPage, ]h5tgi?_l
eJ-nKkg~a
currentPage); C,4e"yynb
int totalPage = getTotalPage(everyPage, fz
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SvF<p3
totalRecords); = dN@Sa/
boolean hasNextPage = hasNextPage(currentPage, )Pv%#P-<
o`-msz
totalPage); 6Z"X}L,*
boolean hasPrePage = hasPrePage(currentPage); }N52$L0[
VI*$em O0
returnnew Page(hasPrePage, hasNextPage, l*G[!u
everyPage, totalPage, X"%gQ.1|{j
currentPage, yJIscwF
o }m3y
beginIndex); vnuN6M{
} 5v*\Zr5ha
jmG~Un M
privatestaticint getEveryPage(int everyPage){ CU!Dhm/U
return everyPage == 0 ? 10 : everyPage; b&U62iq
} La[V$+Y
[Y `W
privatestaticint getCurrentPage(int currentPage){ < =IFcN
return currentPage == 0 ? 1 : currentPage; 7b+6%fV
} ?}Y]|c^W
oQJtUP%
privatestaticint getBeginIndex(int everyPage, int pd$[8Rmj_
a d\ot#V
currentPage){ 4_ML],.
return(currentPage - 1) * everyPage; 6_B]MN!(
} ,PDQzJY
MF'JeM;H
privatestaticint getTotalPage(int everyPage, int 8 LCb+^
o)/ 0a
totalRecords){ @2i9n
int totalPage = 0; Wx#;E9=Im
))Za&S*<
if(totalRecords % everyPage == 0) :g/tZd$G5
totalPage = totalRecords / everyPage; uPvEwq*
C
else {oL>1h,%3?
totalPage = totalRecords / everyPage + 1 ; xoME9u0x4
1|:KQl2q
return totalPage; UPGtj"2v-
} s5.CFA
*0ro0Z|Iq
privatestaticboolean hasPrePage(int currentPage){ 6!bsM"F
return currentPage == 1 ? false : true; Q,Eo mt
} ^<6[.)
gRzxLf`K
privatestaticboolean hasNextPage(int currentPage, VIbq:U
E{vbO/|kf
int totalPage){ N2o7%gJw
return currentPage == totalPage || totalPage == *m (=V1"
4skD(au8
0 ? false : true; %a7$QF]
} @ Nm@]q
~}Pfu
$/ ],tSm
} |uJ%5y#
Dha1/g1q
~$J2g
ia?
c0xL
B)UZ`?>c
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。 w32y3~
9-
#R)4_
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 fN2lLn9/u
y1#1Ne_
做法如下: L"aeG
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \{D"
!e
7j{?aza
的信息,和一个结果集List: ),!qTjD
java代码: 6S{l'!s'
Fk;Rfqq
ugBCBr
/*Created on 2005-6-13*/ _e2=ado
package com.adt.bo; }-`4DHgq
G+m }MOQP7
import java.util.List; rmOj
'c~4+o4co
import org.flyware.util.page.Page; W%Fv p;\`
moE2G?R
/** [N'h%1]\
* @author Joa .]K%G\*`:
*/ VtohL+
publicclass Result { h@BY]80
uw8f ~:LT
private Page page; !`r$"}g
)M^
gT}M
private List content; ]_$[8#kg
w2'5#`m
/** 5-A\9UC*@
* The default constructor &nK<:^n
*/ ./~(7o$
public Result(){ *K;~!P
super(); `0R./|bv\I
} o !7va"
d"Y{UE
/** w2J<WC+_<
* The constructor using fields 6w7 7YTJ
* @j/&m]6%-D
* @param page f
*)Z)6E
* @param content Q59W#e)
*/ D&zle~" J
public Result(Page page, List content){ F:ELPs4"
this.page = page; &c #N)U
this.content = content; T]$U""
} #A.@i+Zv
:gC#hmm^
/** BJ0?kX@
* @return Returns the content. 'B}qZCy W
*/ 048kPXm`
publicList getContent(){ XX~,>Q}H=
return content; M^I(OuRMeI
} hv+zGID7
PI<vxjOK`
/** %XTI-B/K
* @return Returns the page. 2T`!v
*/ yLcEX
public Page getPage(){ Xm&L
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return page; g,Y/M3>(
} Ap !lQ>p
w*Ihk)
/** "7`<~>9t.
* @param content .|=\z9_7S8
* The content to set. C7?/%7{
*/ et+0FF
,
public void setContent(List content){ w#J2 wS
this.content = content; A)KZa"EX
} |K~Nw&rZ]
]%(2hY~i
/** y> (w\K9W
* @param page xLn%hxm?,
* The page to set. H[|~/0?K
*/ d!{r v
publicvoid setPage(Page page){ zMJT:7*`|
this.page = page; Wez5N
} Q=:|R3U/
} BORA(,
U;I9 bK8
Aa]"
t:c.LFrF
-.3w^D"l
2. 编写业务逻辑接口,并实现它(UserManager, @|)Z"m7
L8n|m!MOD
UserManagerImpl) nF/OPd
java代码: ~_ a-E
$]8Q(/mbK
F<w/PMb
/*Created on 2005-7-15*/ RT5T1K08I
package com.adt.service; MY/}-*|
LIdF 0
import net.sf.hibernate.HibernateException; h1(4Ic
Np)lIGE
import org.flyware.util.page.Page; J.
@9zA&
IO> yIU[
import com.adt.bo.Result; GH
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DeYV$W
B
/** yppo6HGD
* @author Joa D3A/l
*/ 5M_H
NWi4
publicinterface UserManager { p<;0g9,1
,Lt[\_
public Result listUser(Page page)throws iyog`s c
Xry47a
)
HibernateException; %07SFu#
l@:0e]8|o
} $mB;K]m
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\|ao`MMaD<
v.ui!|c
b u"!jHPB
java代码: a'z7(8$$
~v"L!=~G;a
1i] ^{;]
/*Created on 2005-7-15*/ FCn_^l)EA
package com.adt.service.impl; fxIf|9Qi`
sNwI0o
import java.util.List; snikn&
i 3SHg\~Z
import net.sf.hibernate.HibernateException; yCX?!E;La
,v&(Y Od
import org.flyware.util.page.Page; 8JD,u
import org.flyware.util.page.PageUtil; <Ok3FE.K
o8vug$=Z
import com.adt.bo.Result; IqGdfL6[(
import com.adt.dao.UserDAO; A +)`ZTuO
import com.adt.exception.ObjectNotFoundException; 2Wb]4-
import com.adt.service.UserManager; F}qc0
Hq 188<
/** T,tdL
N-
* @author Joa j8`BdKg
*/ u~-8d;+?y
publicclass UserManagerImpl implements UserManager { eR" <33{
;({W#Wa
private UserDAO userDAO; NgCvVWto
@ry_nKr9
/** /H==Hm/
* @param userDAO The userDAO to set. *WT`o>
*/ AzxXB
publicvoid setUserDAO(UserDAO userDAO){ 7\q~%lDE
this.userDAO = userDAO; 6MkP |vr6
} w+{LAS
\'bzt"f$j
/* (non-Javadoc) O0y_Lm\
* @see com.adt.service.UserManager#listUser 09Cez\0
0K2`-mL
(org.flyware.util.page.Page) C2Tyoza
*/ xZv#Es%#
public Result listUser(Page page)throws ?3xzd P
jalg5`PU0
HibernateException, ObjectNotFoundException { @|%2f@h
int totalRecords = userDAO.getUserCount(); t`mV\)fa
if(totalRecords == 0) Wiu"k%Qsh
throw new ObjectNotFoundException I.k
*GW
.VzT:4-<Q"
("userNotExist"); 1y4
page = PageUtil.createPage(page, totalRecords); ^`>/.gL
List users = userDAO.getUserByPage(page); $p?aVO
returnnew Result(page, users); {!dVDf_
} !I
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Y.r+wc]
} h2""9aP!
5[u]E~Fl}
,WB{i^TD
(*)hD(C5
hfy_3} _
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 b%/ 1$>_
{jX2}
询,接下来编写UserDAO的代码: Per1IcN
3. UserDAO 和 UserDAOImpl: >J>[& zS
java代码: %- 0t?/>
)%@J=&G8TT
/RC7"QzL
/*Created on 2005-7-15*/ >&5DsV.B
package com.adt.dao; ]wG{!0pl
NPe%F+X
import java.util.List; 4Wm@W E
Tyf`j,=
import org.flyware.util.page.Page; 7VF LJrt
:zF,A,)
import net.sf.hibernate.HibernateException; 'u b@]ru|
ITT@,
/** OH(waKq2I
* @author Joa ;VO:ph4Aj
*/ <<R*2b
publicinterface UserDAO extends BaseDAO { b`O'1r\Y;
DZPPJ2 }
publicList getUserByName(String name)throws r?
E)obE
Da&]y
HibernateException; fDU!~/#
V /V9B2.$
publicint getUserCount()throws HibernateException; UQ@L V~6{R
?oHpFlj
publicList getUserByPage(Page page)throws u($!z^h
R',rsGd`6j
HibernateException; ^qD$z=z-
|2n4QBH!
} Y\?"WGL)p
FE|JHh$
@wNG{Stj
6MMOf\
OA"q[s
java代码: JB[~;nLlC
czRFMYE
hp-<2i^"!
/*Created on 2005-7-15*/ Y^EcQzLw
package com.adt.dao.impl; i5Yb`Z[Y
l#Y,R 0
import java.util.List; XLOh7(
D2B%0sfl~
import org.flyware.util.page.Page;
k5.Lna
X))/ m[_[
import net.sf.hibernate.HibernateException; <s<n
import net.sf.hibernate.Query; KEjWRwN
O5nD+qTQ#
import com.adt.dao.UserDAO; .MoU1n{Yc
RO/FF<f
/** GH:jH]u!V
* @author Joa {go;C}
*/ Xg!{K3OS
public class UserDAOImpl extends BaseDAOHibernateImpl
MC.)2B7
C
mWgcw1
implements UserDAO { V7fq4O^:
::{Q1F
/* (non-Javadoc) 2?ez,*-[
* @see com.adt.dao.UserDAO#getUserByName UIN<2F_
hAnPXiD
(java.lang.String)
>rKIG~P_
*/ !0L Wa"
publicList getUserByName(String name)throws My[pr_xg
;LSANr&
HibernateException { MPg)=LI
String querySentence = "FROM user in class c>:wd@w
ywm8N%]v
com.adt.po.User WHERE user.name=:name"; tm RXgTS
Query query = getSession().createQuery k],Q9
X296tA>C`
(querySentence); 9BBmw(M}
query.setParameter("name", name); kr:^tbJ
return query.list(); a:IC)]j$_
} EF}\brD1
nIy}#MUd|q
/* (non-Javadoc) Y}|X|!0x
* @see com.adt.dao.UserDAO#getUserCount() ca*DZG/
*/ PB`Y
g
publicint getUserCount()throws HibernateException { xvl#w
int count = 0; 3z9d!I^>k
String querySentence = "SELECT count(*) FROM &n}f?
qCpp6~]Um
user in class com.adt.po.User"; }1i`6`y1
Query query = getSession().createQuery gANuBWh8T
Rmt~,cW!\
(querySentence); ][h%UrV
count = ((Integer)query.iterate().next
?2{Gn-{
&LZn
FR
()).intValue(); {xB!EQ"
return count; s.N/2F&*W
} Pz |>"'
q{I%Q)t)gU
/* (non-Javadoc) 1
A
!bE
* @see com.adt.dao.UserDAO#getUserByPage Ed,~1GanY
sn$9Shgh
(org.flyware.util.page.Page) YPK(be_|I
*/ +tIF
h'
publicList getUserByPage(Page page)throws >xYpNtEs
m6&~HfwN
HibernateException { O/a4]r+_
String querySentence = "FROM user in class ]kRfB:4ED
_] sn0rX
com.adt.po.User"; 1AfnzGvA
Query query = getSession().createQuery
}mq6]ZrK
dIa+K?INX
(querySentence); xU>WEm2
query.setFirstResult(page.getBeginIndex()) a# y;dK
.setMaxResults(page.getEveryPage()); l%pu HZ)t
return query.list(); Ou!2[oe@M
} b vr^zH,C
xH(lm2kvT
} Qu"\wE^.`
}c`"_L
#Z`q+@@]A
AFDq}*2Qb
G"U9E5O
至此,一个完整的分页程序完成。前台的只需要调用 YYl 4"l
~tUl}
userManager.listUser(page)即可得到一个Page对象和结果集对象 kmsb hYM)
eH3JyzzP,
的综合体,而传入的参数page对象则可以由前台传入,如果用 &5spTMw8
O-~7b(Z
webwork,甚至可以直接在配置文件中指定。 &<5zqsNJ\a
wh\}d4gN
下面给出一个webwork调用示例: Ng>5?F^v
java代码: l7259Ro~
_A5e{Gb
(vPN5F
/*Created on 2005-6-17*/ _jI,)sr4ic
package com.adt.action.user; XQs1eP'{
zRl3KjET
import java.util.List; :W:K:lk
lhz{1P]s
import org.apache.commons.logging.Log; qL&[K>2z
import org.apache.commons.logging.LogFactory; }Jve cRtg1
import org.flyware.util.page.Page; ox>^>wR*
.TMs bZ|j
import com.adt.bo.Result; ^aMg/.j
import com.adt.service.UserService; 5uNJx5g
import com.opensymphony.xwork.Action; YX7L?=;.@
*:YiimOY"
/** C'+YQ]u
* @author Joa KRLQ #,9
*/ WJndoB.f[2
publicclass ListUser implementsAction{ udF~5w
H
/-ch`u md
privatestaticfinal Log logger = LogFactory.getLog /vde2.|
w%VU/6~
(ListUser.class); tl4V7!U@^z
C:* *;=.
private UserService userService; ,p@y]
cr
-p&" y3<p
private Page page; :O?MSS;~
FLCexlv^
privateList users; \H~T>j{N
axRV:w;E<
/* *vN-Vb^2i)
* (non-Javadoc) MS>Ge0P("~
* P[#e/qnXu|
* @see com.opensymphony.xwork.Action#execute() RtP2]O(F
*/ Xy&A~F
publicString execute()throwsException{ V _/%b)*
Result result = userService.listUser(page); e*(!^Q1
page = result.getPage(); }DEg-j,F
users = result.getContent();
0hNA1Fh{U
return SUCCESS; }[};IqVaK
} _476pZ_
sw oQ'
/** BB$>h}
* @return Returns the page. [0[i5'K:
*/ k>Vci{v
public Page getPage(){ kr5">"7
return page; VimE@ Hz
} He/8=$c%
+I:Unp
/** %2/EaaR
* @return Returns the users. ks qQM
*/ 6V:U(g
publicList getUsers(){ HTcb_a
return users; 2K6qY)/_
} 3{^9]7UC
18d4fR
/** 4 Y9`IgQ
* @param page #u(^0'
P
* The page to set. ]G=L=D^cK
*/ W$;,CU.v
publicvoid setPage(Page page){ V-2(?auZd
this.page = page; |t&>5HM
} _LUhZlw
\0I_<
/** #n#}s
* @param users VUGmi]qd
* The users to set. I-)+bV
G
*/ l0w]`EE
publicvoid setUsers(List users){ m@F`!qY~Y\
this.users = users; Q&ptc>{bH6
} x8\?}UnB
y`5
9A
/** Jr!JHC9i
* @param userService D~iz+{Q4
* The userService to set. Uh4%}-;
*/ !bx;Ta.
publicvoid setUserService(UserService userService){ )Y0!~#
`
this.userService = userService; .x.]`b(
} ")5":V~fN
} rgv?gaQ>
l
-m fFN
w"|L:8
1..+F0U
a=1@*ID
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, 8.=BaNU
nFe<w
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 q=m'^
,gPS
oj<gD
么只需要: $am$EU?s
java代码: t!X.|`h
wqs?828x
Hqx-~hQO
<?xml version="1.0"?> e@07
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [`[|l
#&k5d:
1.0//EN" "http://www.opensymphony.com/xwork/xwork- JPUW6e07o
a:`E0}C
1.0.dtd"> 8z`G,qh
4G0m\[Du
<xwork> |O+H[;TB6
)
7@ `ut
<package name="user" extends="webwork- F4z{LhZ
\fdv]f
interceptors"> `r':by0M
D|p9qe5%
<!-- The default interceptor stack name 9};8?mucr
_,0
--> $G+@_'
<default-interceptor-ref Y%^w:|f^
5yo%$i8I
name="myDefaultWebStack"/> ~&{S<Wl
'ya{9EdlT
<action name="listUser" H;LViP2K*
=zPCrEk0
class="com.adt.action.user.ListUser"> 7"x;~X
<param S Lj!v&'
iByf{ I>+
name="page.everyPage">10</param> pRpBhm;iJ
<result ]^7@}Ce_
h"Q8b}$^)
name="success">/user/user_list.jsp</result> wv1iSfW
</action> 5m 4P\y^a
=R|HV;9 h
</package> ]|ag
QO~P7r|A
</xwork> 2- h{N
lNh70G8^p
AKfDXy
((;!<5-`s
Eyqa?$R
@n /nH?L
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 'sKk"bi;0
$( kF#
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 ]:- mbgW
M"Hf :9Rk
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ZJJY8k `
hWLA<wdb
lgy<?LI\
!i}w~U<
tSUEZ62EY
我写的一个用于分页的类,用了泛型了,hoho 5Ln,{vsv
G~[x
3L'
java代码: 1n8/r}q'H
&wawr2)}
H$t_Xw==
package com.intokr.util; &PHTpkaam
Bm<`n;m
import java.util.List;
ltSU fI
k]|~>9eY]
/** $8h%a
8I
* 用于分页的类<br> o5PO=AN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9Q.Yl&A
* vn8aFA
* @version 0.01 o:'MpKm
* @author cheng )dw'BNz5hT
*/ *:7rdzn
public class Paginator<E> { }R2u@%n{
privateint count = 0; // 总记录数 J]'zIOQ
privateint p = 1; // 页编号 ^uc=f2=>,
privateint num = 20; // 每页的记录数 G e@{_
privateList<E> results = null; // 结果 `/+>a8
h,N?Ab'S
/** i1d'nxk6
* 结果总数 EME|k{W
*/ ;JT-kw6l5K
publicint getCount(){ `$9x 1dx
return count; a58H9w"u)
} fTec
9W5lSX#^;
publicvoid setCount(int count){ *N<]Xy@
this.count = count; ,ZNq,$j
} V f&zL
Sgr
O0v}43J[
/** PFjL1=7I
* 本结果所在的页码,从1开始 9$w.9`Py
* qe#tj/aZ
* @return Returns the pageNo. 2]*OQb#O6e
*/ M|h3Wt~7
publicint getP(){ !f[_+CD
return p; TIDO@NwF
} Wn2NMXK
@Nx9)
/** hn@08t G
* if(p<=0) p=1 U7F!Z(
9
* 90rol~M&
* @param p =UQ3HQD
*/ \}b%E'+_T
publicvoid setP(int p){ vvMT}-!
if(p <= 0) r l%
p = 1; 7JH6A'&
this.p = p; wwZ ,;\
} ~<bZ1TD
\M^bD4';>
/** rM%1GPVob
* 每页记录数量 4+8@`f>s
*/ g3y~bf
publicint getNum(){ {;1\+f
return num; H7n>Vx:L-
} 8GUX{K
C1)!f j=
/** k y7Gwc
* if(num<1) num=1 1))8
A@,
*/ oG\Vxg*
publicvoid setNum(int num){ H1./x6Hr
if(num < 1) S=5o
< 1
num = 1; lL3U8}vn
this.num = num; +r2-S~f3N
} CA~-rv
d$!RZHo10V
/** {EQOP]
* 获得总页数 g) jYFfGfH
*/ ~$^XP.a.
publicint getPageNum(){ $U~]=.n
return(count - 1) / num + 1; U5de@Y
} 3]S$ih&A
gM:".Ee
/** q 2E_A
* 获得本页的开始编号,为 (p-1)*num+1 f
;n3&e0eC
*/ Fx.=#bVX7
publicint getStart(){ %h!B^{0
return(p - 1) * num + 1; sO@Tf\d
} zrb}_
B]tQ(s~
/** O\r0bUPE
* @return Returns the results. (jE9XxQY
*/ 6i/(5 nQ
publicList<E> getResults(){ 26h21Z16q
return results; b]KBgZ
} R\[e!g*I
~4'$yWG
public void setResults(List<E> results){ FZnw0tMq
this.results = results; 3!]rmZ-W
} (GfZ*
=Xr.'(U
public String toString(){ KZf+MSq?
B
StringBuilder buff = new StringBuilder Q~Wqy~tS
gPPkT"
(); WNtW|IV
buff.append("{"); ww1[rCh\+
buff.append("count:").append(count); ]/L0,^RI
buff.append(",p:").append(p); <e6#lFQqK
buff.append(",nump:").append(num); 8":Q)9;%
buff.append(",results:").append SmO~,2=
K}Qa~_
(results); WpvhTX
buff.append("}"); %pCTN P
return buff.toString(); es7=%!0
} <a3WKw
"w<#^d_6
} R:qW;n%AF
H Pz+Dm
(E1~H0^