Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Tr0V6TS7
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ox_h9=$-
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 +n[wkgFd
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Bh,)5E^m
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分页支持类: RLz`aBT
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java代码: d?M!acB
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package com.javaeye.common.util; ;Uqx&5P}
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import java.util.List; n
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publicclass PaginationSupport { wUCDJY:,1
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publicfinalstaticint PAGESIZE = 30; G0QXf
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privateint pageSize = PAGESIZE; ; G59}d
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privateList items; ?>.g;3E$
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privateint totalCount; boF4d'g"
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privateint[] indexes = newint[0]; 2 Z`$
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privateint startIndex = 0; gLaO#cQ%
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public PaginationSupport(List items, int ^?X ^+
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totalCount){ a^XTW7]r
setPageSize(PAGESIZE); d0A\#H_&
setTotalCount(totalCount); ]v@ tZ}
setItems(items); H@2v<e@
setStartIndex(0); ]PzTl {]
} o;VkoYV
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public PaginationSupport(List items, int pl#o!j( i
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totalCount, int startIndex){ RC8)f8n
setPageSize(PAGESIZE); ]\a\6&R
setTotalCount(totalCount); siRnH(^J
setItems(items); 38U5^`
setStartIndex(startIndex); n.a=K2H:V
} CFBUQMl>
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public PaginationSupport(List items, int {wpMg
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totalCount, int pageSize, int startIndex){ 6>=-/)p}
setPageSize(pageSize); Z9"{f)T
setTotalCount(totalCount);
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setItems(items); -; us12SZ
setStartIndex(startIndex); Pu$kj"|q*[
} 4aalhy<j
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publicList getItems(){ }
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return items; zL)1^[%O9
} u+mjguIv
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publicvoid setItems(List items){ %UUp=I
this.items = items; c
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} 3yHb!}F
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publicint getPageSize(){ V6@*\+:3)
return pageSize; vLv|SqD
} ,30FGz^i
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publicvoid setPageSize(int pageSize){ |&elZ}8
this.pageSize = pageSize; Q?
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} er["NSo
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publicint getTotalCount(){ VM-qVd-
return totalCount; c$,c`H(~
} V17>j0Ev$W
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publicvoid setTotalCount(int totalCount){ lfxuc7Rdla
if(totalCount > 0){ :"M9*XeHO
this.totalCount = totalCount; w8 ?Pb$Fe
int count = totalCount / 0Y5LDP
/*u#Ba<<
pageSize; tJUVw=
if(totalCount % pageSize > 0)
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count++; ruZYehu1W
indexes = newint[count]; Q3'fz 9v
for(int i = 0; i < count; i++){ qpb/g6g
indexes = pageSize * h]kn%?fpmB
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} c@RT$Q9j
}else{ QuSV&>T\
this.totalCount = 0; >EBZ$ X
} vC)"*wYB{
} Dh
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publicint[] getIndexes(){ +<S9E'gT3V
return indexes; wVx,JL5Jr
} >%9^%p^
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publicvoid setIndexes(int[] indexes){ fA"<MslKLK
this.indexes = indexes; `+roQX.p
} 8 ne/=N|,
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publicint getStartIndex(){ j(0Ilx|7v
return startIndex; xLA~1ZSVJw
} S4L-/<s[*
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publicvoid setStartIndex(int startIndex){ Xl#Dw bx
if(totalCount <= 0) mfZ)^X
this.startIndex = 0; JDkCUN 5
elseif(startIndex >= totalCount) Dq?E\
this.startIndex = indexes cb+l"FI7
#X#8ynt
[indexes.length - 1]; EbCIIMbe"
elseif(startIndex < 0) As0 B\
this.startIndex = 0; Iha[Gu
else{ B9YsA?hg
this.startIndex = indexes (@+h5@J[`I
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[startIndex / pageSize]; >L^xlm%7o
} +fM&su=wl
} 4avc=Y5
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publicint getNextIndex(){ #>=8w9]
int nextIndex = getStartIndex() + Nu@5 kwH
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pageSize; 0x\2#i
if(nextIndex >= totalCount) W]_g4,T>
return getStartIndex(); F$i$a b
else N&"QKd l
return nextIndex; 0E-pA3M6
} @M=$qO_$9
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publicint getPreviousIndex(){ 8"x9#kyU<3
int previousIndex = getStartIndex() - R"Kz!NTB
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pageSize; L=RGL+f1_
if(previousIndex < 0) fp{G|.SA
return0; ll%G!VR
else i
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return previousIndex; }z
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} TiyUr [
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} hk_g2g
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抽象业务类 .xl.P7@JJ
java代码: Jt]&;0zn2
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/** e[{mVhg4E
* Created on 2005-7-12 fagM7)x
*/ =IZ[_ /@
package com.javaeye.common.business; 9Kbw
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import java.io.Serializable; u]M\3V.
import java.util.List; {q,?<zBzu
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import org.hibernate.Criteria; ?YBaO,G9o
import org.hibernate.HibernateException; 6\n?48x}
import org.hibernate.Session; Xwq]f:@V
import org.hibernate.criterion.DetachedCriteria; Y5Z!og
import org.hibernate.criterion.Projections; VI_+v[Hk/
import DnFjEP^
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org.springframework.orm.hibernate3.HibernateCallback; % (<(Y
import c-B/~&
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org.springframework.orm.hibernate3.support.HibernateDaoS BpH%STEN
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upport; Kkv<"^H
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import com.javaeye.common.util.PaginationSupport; c}-(. eu
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public abstract class AbstractManager extends 2*2:-ocl$
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HibernateDaoSupport { BzN@gQo
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privateboolean cacheQueries = false; U~H?4Izl=
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privateString queryCacheRegion; ?S tsH
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publicvoid setCacheQueries(boolean -RMi8{
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cacheQueries){ V.=lGhi
this.cacheQueries = cacheQueries; 9Ah[rK*}
} uMmXs%9T
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publicvoid setQueryCacheRegion(String 80;n|nNB
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queryCacheRegion){ ke%pZ7{u
this.queryCacheRegion = )9L/sKz
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queryCacheRegion; ub K7B |p
} .`p&ATgv
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publicvoid save(finalObject entity){ 9P WY52!
getHibernateTemplate().save(entity); GF$`BGW
} A''pS
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publicvoid persist(finalObject entity){ QHlU|dR)Ry
getHibernateTemplate().save(entity); V/%~F6e
} o:p
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publicvoid update(finalObject entity){ se9>.}zZN
getHibernateTemplate().update(entity); '0Q,
} 'LS z f/w
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publicvoid delete(finalObject entity){ A1i!F?X
getHibernateTemplate().delete(entity); ]$b2a&r9
} $8~e}8dt|
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publicObject load(finalClass entity, 7h9U{4r: M
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finalSerializable id){ ('[TLHP
return getHibernateTemplate().load >3.X?
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(entity, id); ^Q}eatEn
} PBjmGwg7
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publicObject get(finalClass entity, a;AzY'R
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finalSerializable id){ #q\x$
return getHibernateTemplate().get 3G}AH E4
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(entity, id); 7:E!b=o#
} yYZxLJ='
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publicList findAll(finalClass entity){ TFQ!7'xk)
return getHibernateTemplate().find("from 9ooY?J
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" + entity.getName()); eOT+'[3"
} Di.3113t
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publicList findByNamedQuery(finalString PJ4(}a
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namedQuery){ w8Sv*K
return getHibernateTemplate 8hanzwoJ:
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().findByNamedQuery(namedQuery); +j14Q$
} l `9t}
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publicList findByNamedQuery(finalString query, ,5
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finalObject parameter){ w4,Ag{t>
return getHibernateTemplate (.Y/
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().findByNamedQuery(query, parameter); $g9**b@
} m7c*)"^
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publicList findByNamedQuery(finalString query, E>LkJSy=
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finalObject[] parameters){ SMr13%KN/
return getHibernateTemplate Ga>uFb}W~
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().findByNamedQuery(query, parameters); ?4H#G)F
} #FOqP!p.E
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publicList find(finalString query){ _n8GWBi
return getHibernateTemplate().find .R*!aK
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(query); !`JHH&
} inb^$v
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publicList find(finalString query, finalObject ]
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parameter){ Jq.lT(E8D
return getHibernateTemplate().find gU^$Sx7'
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(query, parameter); 2aZw[7s
} 'nQVj
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public PaginationSupport findPageByCriteria D%mXA70
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(final DetachedCriteria detachedCriteria){ {#P`^g
return findPageByCriteria WW2Ob*
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); \6?A!w~6
} =h6
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public PaginationSupport findPageByCriteria c}*2$1
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(final DetachedCriteria detachedCriteria, finalint '3]p29v{
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startIndex){ &c(WE
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return findPageByCriteria AsS$C&^
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(detachedCriteria, PaginationSupport.PAGESIZE, B_U{ s\VY
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startIndex); {Sl57!U5
} GuZ( &G6*
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public PaginationSupport findPageByCriteria P7ph}mB
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(final DetachedCriteria detachedCriteria, finalint e~ aqaY~}
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pageSize, FlfI9mm
finalint startIndex){ k:2QuG^
return(PaginationSupport) ]eQV,Vt
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getHibernateTemplate().execute(new HibernateCallback(){ J89Dul l
publicObject doInHibernate hmx=
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(Session session)throws HibernateException { =cN&A_L(
Criteria criteria = {e|*01hE
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detachedCriteria.getExecutableCriteria(session); cYx4~ V^
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount E3@QI?n^^
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()).uniqueResult()).intValue(); 4L-:*b_v\
criteria.setProjection +$xeoxU>;
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(null); JGC=(;
List items = )eUW5
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criteria.setFirstResult(startIndex).setMaxResults 9_\'LJ
t
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(pageSize).list(); ml@2wGyf
PaginationSupport ps = KbL V'%D
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new PaginationSupport(items, totalCount, pageSize, RH}A
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startIndex); i>EgG5iJ
return ps; uE[(cko
} "#v=IJy&r
}, true); 1)}=bhT
} f<+4rHT
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public List findAllByCriteria(final [Q\GxX.
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DetachedCriteria detachedCriteria){ 79\JxiSB
return(List) getHibernateTemplate yNm:[bOER
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().execute(new HibernateCallback(){ 5TBp'7 /s~
publicObject doInHibernate Ca%g_B0t
oG$)UTzGc
(Session session)throws HibernateException { bs9aE<j
Criteria criteria = {]z4k[;.h
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detachedCriteria.getExecutableCriteria(session); J$~<V
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return criteria.list(); &a/__c/l
} 5Z4-Z
}, true); >3awn*N
} qQ!1t>j+H
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public int getCountByCriteria(final 2_Wg!bq
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DetachedCriteria detachedCriteria){ T#pk]c6Q
Integer count = (Integer) '0$?h9"
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getHibernateTemplate().execute(new HibernateCallback(){ AmwWH7,g
publicObject doInHibernate IVlf=k
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(Session session)throws HibernateException { SWp1|.=Sm
Criteria criteria = pT?Q#,fh
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detachedCriteria.getExecutableCriteria(session); ~}K5#<
return lnE+Au'
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criteria.setProjection(Projections.rowCount Tz2-Bp]h
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()).uniqueResult(); ,G#.BLH
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} 8A{_GH{:
}, true); .qk]$LJF7
return count.intValue(); 2xw6 5z
} iCP/P%
} 1b8p~-LsU
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用户在web层构造查询条件detachedCriteria,和可选的 K/ &?VIi`z
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 $./bjV%
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PaginationSupport的实例ps。 $3D'4\X~?
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ps.getItems()得到已分页好的结果集 @H !$[m3
ps.getIndexes()得到分页索引的数组 B12$I:x`
ps.getTotalCount()得到总结果数 \,!QJp4
ps.getStartIndex()当前分页索引 mj?16\|]
ps.getNextIndex()下一页索引 xUF_1hY
ps.getPreviousIndex()上一页索引 +l^LlqA
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 s08u @
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 a:~@CUD
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一下代码重构了。 FZB~|3eq{
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我把原本我的做法也提供出来供大家讨论吧: ,wwZI`>-
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首先,为了实现分页查询,我封装了一个Page类: x*oWa,
java代码: d@mo!zu
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/*Created on 2005-4-14*/ 9>/wUQs!]
package org.flyware.util.page; M(|
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/** Ou'?]{
* @author Joa JT[*3h
* ,n2i@?NHZ
*/ EoX_KG{
publicclass Page { n{*e 9Aw
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/** imply if the page has previous page */ Uadr>#C*
privateboolean hasPrePage; A5#y?Aq
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/** imply if the page has next page */ PIcrA2ll
privateboolean hasNextPage; (_*
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/** the number of every page */ `Lyq[zg8
privateint everyPage; l2b{u
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/** the total page number */ O?bK%P]ay
privateint totalPage; N132sN2
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/** the number of current page */ us?&:L|!=
privateint currentPage; ]O:M$ $
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/** the begin index of the records by the current :ZdUx
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query */ `=tyN@VC
privateint beginIndex; ,KW;2t*IQ@
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/** The default constructor */ e^).W3SK]
public Page(){ 'p)Q68;&
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} x_@i(oQ:_
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/** construct the page by everyPage OQ_stE2i
* @param everyPage l52a\/
* */ fF?6j
public Page(int everyPage){ Ru%|}sfd
this.everyPage = everyPage; 2x$x;
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} WbjF]b\
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/** The whole constructor */ y93k_iq$S
public Page(boolean hasPrePage, boolean hasNextPage, 1r`i]1<H
fhp)S",
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int everyPage, int totalPage, ^kj=<+ v#
int currentPage, int beginIndex){ :,]S}R
this.hasPrePage = hasPrePage; H^c0Kh+
this.hasNextPage = hasNextPage; $&-5;4R'0
this.everyPage = everyPage; C;1PsSE+A
this.totalPage = totalPage; Yt1mB[&f^
this.currentPage = currentPage; )@QJ
this.beginIndex = beginIndex; -R+zeu(e'
} H~+xB1
+!>LY
/** \tt'm\_
* @return 3_ 2hC!u!K
* Returns the beginIndex. =DgCC|p
*/ G\Hq/4
publicint getBeginIndex(){ i&ts YnP2
return beginIndex; @h-T:$
} ~^o=a?L`<
mX_)b>iW
/** 9 pKm*n&
* @param beginIndex #qL9{P<}
* The beginIndex to set. W}gVIfe
*/ tjzA)/T,4
publicvoid setBeginIndex(int beginIndex){ ~
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this.beginIndex = beginIndex; '"O&J}s;
} sWxK~Yg
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/** +^Jwo)R'b
* @return c8Pb
* Returns the currentPage. O k(47nC
*/ 3ut_Bt\
publicint getCurrentPage(){ Z] { @H
return currentPage; H`|0-`q
} ;~ee[W$1
26nBBS,;
/** cIZc:
* @param currentPage )+GX<2_
* The currentPage to set. EVz9WY
*/ ~{QEL2
publicvoid setCurrentPage(int currentPage){ *,jqE9:O
this.currentPage = currentPage; #eEvF
} ,V2#iY.%}N
@a;sV!S{
/** /#\?1)jCK
* @return c,BAa*]K
* Returns the everyPage. m^0A?jBrR
*/ GMb!Q0I8
publicint getEveryPage(){ 59MR|Jt
return everyPage; s>J3\PC
} WB;J1TpM7
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/** Q!)z)-hI
* @param everyPage '}zT1F*
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* The everyPage to set. z|%Bh
*/ Jk~UEqr+
publicvoid setEveryPage(int everyPage){ ORtg>az\%
this.everyPage = everyPage; (\uAAW"
} vK'9{q|g
0~.)GG%R>D
/** 8!6<p[_
* @return VVN#
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* Returns the hasNextPage. |$ w0+bV*
*/ g1dmkX
publicboolean getHasNextPage(){ <[FS%2,0mb
return hasNextPage; ])68wqD
} }{#7Z8
7(5]Ry:
/** ZU^Q1}</5
* @param hasNextPage (V^QQ !:
* The hasNextPage to set. !r2}59J
*/ h+
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publicvoid setHasNextPage(boolean hasNextPage){
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this.hasNextPage = hasNextPage; ~Cu lFxu
} l]/> `62
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/** <EOg,"F
* @return M +\rX1T
* Returns the hasPrePage. w0\4Wa
*/ =X<)5IS3
publicboolean getHasPrePage(){ 'H
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return hasPrePage; ;7)OSGR
} krwf8!bI
$<14JEU
/** wo$|~
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* @param hasPrePage )m)h/_
* The hasPrePage to set. CARq^xI-
*/ f};!m=b
publicvoid setHasPrePage(boolean hasPrePage){ |zg=+
this.hasPrePage = hasPrePage; X #H:&*[!
} c;nx59w]q
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/** =nw,*q +
* @return Returns the totalPage. ?@yank|
* ;cnnqT6
*/ tc!!W9{69
publicint getTotalPage(){ 1+VY><=n
return totalPage; (xjqB{U
} aGdpecv
MP_A<F
/** ;sm"\.jF
* @param totalPage Q>##hG:m
* The totalPage to set. p3{x <AO/
*/ {/th`#o4b
publicvoid setTotalPage(int totalPage){ ^n6)YX
this.totalPage = totalPage; |;X?">7NW
} #_JA5W+E
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} (9Fabo\SH
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f%`*ba"v
3w[<cq.!
Q:'qw#P/C
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 pE$|2v
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个PageUtil,负责对Page对象进行构造: ]J8KCjq@
java代码: 2V#c[%vI
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/*Created on 2005-4-14*/ *%P>x}6w3
package org.flyware.util.page; z }FiU[Hs
H9oXZSm
import org.apache.commons.logging.Log; !D.= 'V
import org.apache.commons.logging.LogFactory; JL}hOBqfI
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/** 8MYLXW6
* @author Joa + 1E?He:iQ
* X|lElN
*/ 4GMa5]Ft
publicclass PageUtil { _QC?:mv6-
Tx|SAa=V
privatestaticfinal Log logger = LogFactory.getLog `'A(`. CL
,v$2'm)V
(PageUtil.class); N'lGA;}i
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/** |o; j0
* Use the origin page to create a new page }QX2:a
* @param page w~cq%%
* @param totalRecords (`q6G d
* @return CP F>^Mp#
*/ i/C
-{+}U
publicstatic Page createPage(Page page, int :Ul'(@
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totalRecords){ ZTgAZ5_cz
return createPage(page.getEveryPage(), -@gJqoo>
P ],)
page.getCurrentPage(), totalRecords); rA1zyZlz
} Q5`+eQ?_\
,N))=/
/** `[C v-
* the basic page utils not including exception :$GL.n-?
)$9C` d[
handler Xj})?{FP
* @param everyPage Z,N7nMJf
* @param currentPage Xd19GP!
* @param totalRecords `ohF?5J,
* @return page K&\BwBU
*/ ;S{Ld1;
publicstatic Page createPage(int everyPage, int n}ZBU5_
Hd=D#u=A4{
currentPage, int totalRecords){ L_.xr
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everyPage = getEveryPage(everyPage); mhJOR'2
currentPage = getCurrentPage(currentPage); v4,syd*3|V
int beginIndex = getBeginIndex(everyPage, WW8YB"
"x=@,*Bk
currentPage); ^%4(
%68
int totalPage = getTotalPage(everyPage, ZhJ|ZvJ
9`gGsC
totalRecords); @tjZvRtZ
boolean hasNextPage = hasNextPage(currentPage, XCqfAcNQ
)z4kP09
totalPage); hNR>Hy\
boolean hasPrePage = hasPrePage(currentPage); x#}j3"
PP
kw-Kx4 )
returnnew Page(hasPrePage, hasNextPage, 1TD&&EC
everyPage, totalPage, LF-+5`
currentPage, *"wD&E?
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beginIndex); U7f&N
} Ie`SWg*WL
6!Tf'#TV~!
privatestaticint getEveryPage(int everyPage){ 1 [~|
return everyPage == 0 ? 10 : everyPage; Cn./N aq
} <+i`W7
).O2_<&?F
privatestaticint getCurrentPage(int currentPage){ ]a%\Q2[c
return currentPage == 0 ? 1 : currentPage; A0N ;VYv
} xdTzG4
h?pGw1Q
privatestaticint getBeginIndex(int everyPage, int ~]_jKe4W
m(7_ZiL=
currentPage){ Q&U= jX
return(currentPage - 1) * everyPage; CsST-qxg
} /+JP~K
j|$y)FBX
privatestaticint getTotalPage(int everyPage, int Vo9)KxR
GF.g'wYc)Y
totalRecords){ uwS'*5tU
int totalPage = 0; 3Ns:O2|
C6T 9
if(totalRecords % everyPage == 0) A&_i]o
totalPage = totalRecords / everyPage; B& f~.UH
else =ILo`Q~
totalPage = totalRecords / everyPage + 1 ; 5A=xF j{
Y @ ,e
return totalPage; c,s<q j
} TXk"[>,:H
cF<DUr)Ve
privatestaticboolean hasPrePage(int currentPage){ MvjwP?J]
return currentPage == 1 ? false : true; XkfUPbU
} Y<$"]@w
ABYW1K=
privatestaticboolean hasNextPage(int currentPage, kU9AfAe
U>M>FZ
int totalPage){ apWrcaj
return currentPage == totalPage || totalPage == * jNu?$
Fb4S/_
V
0 ? false : true; %$-3fj7
} I:2jwAl
+z/73s0~
w\Eve:
} _f2iz4
)da8Ru
Hn2Q1lF-ip
oTa+E'q
M(f*hOG{Y
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Fl(ZKpSZU
9*Mg<P"
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 X/D9%[{&
gGz_t,=
做法如下: oM7-1O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 g<jK^\eW
sN/Xofh
的信息,和一个结果集List: leqSS}KU+
java代码: j
W]c9u
^\t">NJ^
x~,?Zj)n?C
/*Created on 2005-6-13*/ x-k/rZ
package com.adt.bo; %[F;TZt
!Dn1pjxc
import java.util.List; L.&Vi"M <@
H0Xda.Y(
import org.flyware.util.page.Page; \nt'I;f
9CSz<[
/** Zl/+HU~
* @author Joa UE](`|4H
*/ 78A4n C
publicclass Result { 'n`$c{N<tM
(
I~XwP&
private Page page; V^H47O;VC
}{PtQc6RL!
private List content; 4y)1*V U:
D#(Pg
/** bJ[1'Es`
* The default constructor blS4AQ?b^
*/ uB9+E%jOdQ
public Result(){ 5{=MUU=
super(); dTNgrW`4
} XX;%:?n
3Sb%]f5(
/** K1yM'6Zw
* The constructor using fields unB "dE
* *Fs^T^ ?r
* @param page Fsdn2{g8U
* @param content [IW7]Fv<F
*/ <0MUn#7'
public Result(Page page, List content){ $a]dxRkz
this.page = page; *gKr1}M
this.content = content; {=Y&q~:8v
} t38T0Ao
7tnzgtal
/** 9]9(o
* @return Returns the content. }gt~{9?c
*/ B) iJH
publicList getContent(){ [! o-F;
return content; z[Qv}pv
} 6ns_4,
e
247>+:7z
/** !r,drb
* @return Returns the page. 3sNq3I
*/ \/G Y0s
public Page getPage(){
p5hP}Z4r
return page; y->iv%
} !Hg#c!eOg
_u!G6
/** XsC bA8Qv
* @param content {,-# ;A*yW
* The content to set. <WmCH+>?r
*/ 2y,wN"qH*
public void setContent(List content){ "+60B0>sc
this.content = content; =+WFx3/
} iE5^Xik,
>?V->7QLP
/**
q\"$~*
* @param page '{~ej:
* The page to set. >oNs_{
*/ pQi -
publicvoid setPage(Page page){ H9?~#GPb
this.page = page; 5{[0Clb)
} k[m-"I%ZFX
} xg&vZzcl
I1jF`xQ&0
G Kr
L
"M]]H^r5
d0d2QRX
2. 编写业务逻辑接口,并实现它(UserManager, D1a4+AyI
aDESO5
UserManagerImpl) 'UKB
pm/
java代码: %,BJkNV
wim}}^H
AmHIG_'
/*Created on 2005-7-15*/ L\5n!(,0
package com.adt.service; UWp(3FQ
+$C5V,H~
import net.sf.hibernate.HibernateException; YDJc@*D
n@f@-d$m\<
import org.flyware.util.page.Page; uU0'y4=
W=/B[@3'
import com.adt.bo.Result; :1Ay_b_J
z!tHn#
/** \}5\^&}_
* @author Joa P=.W.oS
*/ tQ"PCm
publicinterface UserManager { P_}$|zj7
W-MQMHQ
public Result listUser(Page page)throws ul
E\>5O4h
q :gH`5N
HibernateException; 0T*jv! q>
OWU]gh@r
} G7u7x?E:B`
AyWCb
G8@%)$A
\I>,j,c
pLRHwL.
java代码: Z=ho7i
LYT0 XB)A
oPi)#|jcb
/*Created on 2005-7-15*/ B; ~T|ex u
package com.adt.service.impl; JP#m}W
Z"A:^jZ<s
import java.util.List; vjW S35i
H|P.q{(G
import net.sf.hibernate.HibernateException; ?U&onGy
xf |=n
import org.flyware.util.page.Page; /%~`B[4F
import org.flyware.util.page.PageUtil; s`TfNwDvU
U`D"L4},.
import com.adt.bo.Result; R6ywc"xE
import com.adt.dao.UserDAO; Fik*7!XQ8
import com.adt.exception.ObjectNotFoundException; %"o4IYV#
import com.adt.service.UserManager; JAYom%A"
~{xY{qL
/** %
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* @author Joa cOIshT1
*/
uu HWN|
publicclass UserManagerImpl implements UserManager { `":< ]lj
qRNGe8
private UserDAO userDAO; H}A67J9x
XBBsdldZ
/** T2k5\r8
* @param userDAO The userDAO to set. )x]/b=m
*/ a&j
H9
publicvoid setUserDAO(UserDAO userDAO){ )U5AnL
this.userDAO = userDAO; k9a-\UIMet
} (ue;O~
jQc$>M<"o
/* (non-Javadoc) Bp9
u6R
* @see com.adt.service.UserManager#listUser azN<]u@.
w}+jfO9
(org.flyware.util.page.Page) n{|~x":9V
*/ 2: fSn&*/>
public Result listUser(Page page)throws `g3H;E
lBl`R|Gt
HibernateException, ObjectNotFoundException { RxcX\:
int totalRecords = userDAO.getUserCount(); k |M
if(totalRecords == 0) tMC<\e
throw new ObjectNotFoundException Y'58.8hl
g+U6E6}1
("userNotExist"); nD|Bo 9
page = PageUtil.createPage(page, totalRecords); pLNv\M+
List users = userDAO.getUserByPage(page); Ak&eGd$d
returnnew Result(page, users); !M\8k$#"n
} .-uH ax0
kowBB0
} g\GuH?|
|G }qY5_
A(ql}cr
bt"*@NJ$
<t\!g
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 (6!W8x7
~Cm_=[
询,接下来编写UserDAO的代码: c#Y/?F2p
3. UserDAO 和 UserDAOImpl: k,OP*M
java代码: ]9F$/M#
LS
<\%A}
6;Wns'
/*Created on 2005-7-15*/ TZ3"u@ 06
package com.adt.dao; PF~w$ eeQ
PVLLuv
import java.util.List; :;HJ3V;
IZn|1X?}\s
import org.flyware.util.page.Page; oP!oU2eqK
\W4|.[
import net.sf.hibernate.HibernateException; \AQ*T`Dq
4zzJ5,S 1
/** Z^wogIAV
* @author Joa b8@?fC+tm
*/ ;2*hN(
publicinterface UserDAO extends BaseDAO { _<}oBh
b*Sw")#
publicList getUserByName(String name)throws VN]70LFz*i
WCRGqSr4
HibernateException; SI\
O>a9{
1L3+KD~
publicint getUserCount()throws HibernateException; 'A2^K5`3
2Kwr=t
publicList getUserByPage(Page page)throws E?v:7p<
^Q,-4\ec
HibernateException; C)hS^D:
3'2>3Y/7Bb
} ;XagLy
&Zy%Zz
>W>3w
jEu-CU#:
eU(cn8/}
java代码: r?7tI0
.:r
l<.
tK7v&[cI
/*Created on 2005-7-15*/ 6 H{G$[2
package com.adt.dao.impl; b=+3/-d
^J~5k,7jX
import java.util.List; OJ?U."Lxm$
NWue;u^
import org.flyware.util.page.Page; (! a;}V<7
tXfXuHa
import net.sf.hibernate.HibernateException; i4Da 'Uk
import net.sf.hibernate.Query; .VXadgM
s+0n0C
import com.adt.dao.UserDAO; aE(DNeG-H
U2G[uDa;
/** &[b(Lx|i
* @author Joa hm,H3pN
*/ #KUNZW
public class UserDAOImpl extends BaseDAOHibernateImpl O%s7 }bR3
!,<rW<&;
implements UserDAO { Rt.2]eZEJ
&iO53I^r/
/* (non-Javadoc) ^^z_[Ih
* @see com.adt.dao.UserDAO#getUserByName ] kdU]}z
p}]K0F!
(java.lang.String) U _sM==~
*/ M#}k@
;L3
publicList getUserByName(String name)throws Ex<@:
D4jZh+_|S
HibernateException { !ZS5}/ZU
String querySentence = "FROM user in class K |^OnM
@Zzg^1Ilpu
com.adt.po.User WHERE user.name=:name"; T_ j0*A$
Query query = getSession().createQuery /lLG|aAe
0ky3rFSh1
(querySentence); _ |G') 9
query.setParameter("name", name); nmw#4yHYy:
return query.list(); L"L a|
} 0ZJrK\K;
,a3M*}Y~3
/* (non-Javadoc) af_bG;
* @see com.adt.dao.UserDAO#getUserCount() R-6km Tex>
*/ >p29|TFbV
publicint getUserCount()throws HibernateException { 8Xa{.y"
int count = 0; w""
String querySentence = "SELECT count(*) FROM LIRL`xU7
:!w;Y;L:+
user in class com.adt.po.User"; ^Sc48iDc
Query query = getSession().createQuery u}-)ywX
'XI-x[w
(querySentence); X\|h:ce
count = ((Integer)query.iterate().next ]RuH6d2d|
MZt&HbD-
()).intValue(); mr+8[0
return count; ;y.<I&
} Bgs,6:
JqK-vvI
/* (non-Javadoc) @<$_X1)s
* @see com.adt.dao.UserDAO#getUserByPage (,['6k<
D26A%[^O
(org.flyware.util.page.Page) &ER,;^H`6
*/ )2?A|f8
publicList getUserByPage(Page page)throws 6oLZH6fG
]m\:XhI*<
HibernateException { n ==+NL
String querySentence = "FROM user in class i%otvDn1
Lu[xoQ~I
com.adt.po.User"; L{u1_
Query query = getSession().createQuery $uUJV% EX
=UV=F/Af^
(querySentence); oN[#C>#(
query.setFirstResult(page.getBeginIndex()) J1d|L|M
.setMaxResults(page.getEveryPage()); R]y9>5 'U
return query.list(); yHxi^D]
} 1-}$sO c
JT*Pm"}
} An=Q`Uxt/
+zzS
9S{?@*V
vW03nt86
'?b.t2
至此,一个完整的分页程序完成。前台的只需要调用 % ^&D,
k6??+b:rE
userManager.listUser(page)即可得到一个Page对象和结果集对象 y5:al7*P
Cz#3W8jV
的综合体,而传入的参数page对象则可以由前台传入,如果用 -P$E)5?^
Eq'oy~.oV
webwork,甚至可以直接在配置文件中指定。 K9Bi2/N
(N$$N:ac[t
下面给出一个webwork调用示例: EhHW`
java代码: `*Jw[Bnh8
UE/N-K)`
bn8?-
/*Created on 2005-6-17*/ uT{.\qHo
package com.adt.action.user; -O>*`
O>M
ot.R Gpg%
import java.util.List; fSzX /r
nuX W/7M
import org.apache.commons.logging.Log; \ /6m
import org.apache.commons.logging.LogFactory; +hd1|qa4
import org.flyware.util.page.Page; t+BLO<
.X(ocs$}
import com.adt.bo.Result; x_|: 3I
import com.adt.service.UserService; d^jIsE `
import com.opensymphony.xwork.Action; 8v']>5S]#
rFR2c?j8
/** !YEU<9
* @author Joa
js8\"
*/
Ss{
publicclass ListUser implementsAction{ Zc57] ~
-Fs^^={Q
privatestaticfinal Log logger = LogFactory.getLog b3!,r\9V
2F#R;B#2
(ListUser.class); 6Bfu89
=rDIU&0Y
private UserService userService; 7w=%aW|
zwKm;;v8
private Page page; MF^I] 7_
xj!_]XJ^w
privateList users; =xX\z\[A
$MG. I[h
/* JSQ*8wDcl
* (non-Javadoc) <ArP_!
`3
* ^R4eW|H
* @see com.opensymphony.xwork.Action#execute() @Q atgYu
*/ N:@C%
UW}
publicString execute()throwsException{ Cz_chK4
Result result = userService.listUser(page); <ST#<
$%
page = result.getPage(); /Iu._2
users = result.getContent(); !&Q3>8l
return SUCCESS; *ad"3>
} Lay+)S.ta[
~!!>`x
/** YA>du=6y\
* @return Returns the page. 1H_#5hd
*/ b_ |
public Page getPage(){ ]4>[y?k34
return page; N+PW,a
} HYPFe|t/
{P#&e>)v{
/** ^q,KRut
* @return Returns the users. )gCHwu
*/ gH0B[w ]
publicList getUsers(){
Xze
return users; (;a
O%
} E `)p,{T
|Tz4 xTK
/** *[7,@S/<F
* @param page L/GM~*Xp(O
* The page to set. l1N{ujM
*/ t{>66jm\R
publicvoid setPage(Page page){ j78xMGKO
this.page = page; IR%a+;Xs
} C<fNIc~.
h ;5
-X7
/** asW1GZO
* @param users c`X'Q)c&K
* The users to set. *4qsM,t
*/ u6y\ GsM.a
publicvoid setUsers(List users){ &U xN.vl
this.users = users; Oyq<y~}
} MZw%s(lv
Whd4-pR8
/** 9rao&\eH
* @param userService %1VMwqC]E
* The userService to set. 5.[{PJ]bq
*/ ''BP4=r5n
publicvoid setUserService(UserService userService){ e|Sg?ocR
this.userService = userService; ,0 &lag
} e^Xij Id.
} Ip4NkUI3T
bOck^1Hk y
[l#WS
&OhKx
4!k={Pd
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, sjTsaM;<
i8B%|[nm
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 % C
3jxt
6eDIS|/
么只需要: 6>=>Yj
java代码: ;7`<.y
Rc6
)v
Y[~6f,?^
<?xml version="1.0"?> eF8`an5S
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 5h:SH]tn8]
o@>c[knJ
1.0//EN" "http://www.opensymphony.com/xwork/xwork- uAjGR
Q"hI !PO+
1.0.dtd"> l(]\[}.5
4G>|It
<xwork> j^%i?BWw
3yKI2en"
<package name="user" extends="webwork- 7t04!dD}
K%pmE?%,8
interceptors"> ~o/^=:*
99ha/t
<!-- The default interceptor stack name g
Go
:):Y6)giBD
--> f]'@Vt>
<default-interceptor-ref #`p>VXBj!
Pm1
"
0
name="myDefaultWebStack"/> Nu_w@T\l
m|]^f;7z
<action name="listUser" 4C*3#/TR
sRZ:9de+
class="com.adt.action.user.ListUser"> _"sRL}-Z
<param Mb>6.l
R$fna[Xw@/
name="page.everyPage">10</param> `U g.c
<result ,#E5 /'c`
13QCM0#
name="success">/user/user_list.jsp</result> zJnVO$A'
</action> -1_Z*?=-
q9
;\B&
</package> wi9|
'u3+k.
</xwork> $1?X%8V
kW!:bh
/J+)P<_ A
9/$P_Q:3
&tgvE6/V
;Bb5KD
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 *h4m<\^U
q8h{-^"
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。 z}8YrVr@
fv_wK_.
%:
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 0l6iv[qu5w
,>UmKrYo
=|!~0O
.zAafi0
cx,A.Lc
我写的一个用于分页的类,用了泛型了,hoho VjqdKQeVq
2SJh6U
java代码: 9Bk}g50$#
~yi&wbTjM
N 9&@,3
package com.intokr.util; Z]S0AB.Z@
5dp#\J@
import java.util.List; \Ep/'Tj&
12PE{Mut
/** y|Y3,s
* 用于分页的类<br> 3=l-jGJk
* 可以用于传递查询的结果也可以用于传送查询的参数<br> XC1lo4|
* \r%Vgne-g
* @version 0.01 W{+0iAYnp
* @author cheng QiweM?-
*/ {@ y,
public class Paginator<E> { NydW9r:T
privateint count = 0; // 总记录数 i 9tJHeSm
privateint p = 1; // 页编号 Zax]i,Bx
privateint num = 20; // 每页的记录数 W>s'4C`
privateList<E> results = null; // 结果 $l;tP
IVzA>Vd
/** IA`8ie+
* 结果总数 ePRM v
*/ .r| vz6tU?
publicint getCount(){ O|&TL9:
return count; 4D8y b|o
} |~uzQU7
]2Fo.n
publicvoid setCount(int count){ *z"1MU
this.count = count; ,okJ eZ
} C9g~l}=$&
[a)~Dui0@\
/** a61eH )a
* 本结果所在的页码,从1开始 !$xEX,vj|W
* 3d'ikkXK
* @return Returns the pageNo. w52HN;Jm
*/ D^s0EW-E
publicint getP(){ ~`>26BWQz
return p; q AVfbcb
} /9+A97{
?3TK7]1V:
/** aho<w+l@
* if(p<=0) p=1 .-u k
* ?> M oV5
* @param p yFU2'pB
*/ fAM4Q
publicvoid setP(int p){ {.D2ON
if(p <= 0) "">fn(
p = 1; 9poEUjBI
this.p = p; ;Jbc'V'fm
} "p~]m~g
FX|lhwmc(
/** zj$_iB`9
* 每页记录数量 h>^jq{yu
*/ J ]Gc
publicint getNum(){ K?Xo3W%K
return num; t2-nCRXEP
} vzyI::f?
v_ nBh,2
/** KG-k$glD
* if(num<1) num=1 BtpjQNN
*/ Xk&F4BJQk<
publicvoid setNum(int num){ gLxT6v5wk.
if(num < 1) i9@;,4f
num = 1; '^F|k`$r
this.num = num; ]~
#+b>
} Gx h~
! F;<xgw
/** zA'gb'MmW
* 获得总页数 cdJ`Gk
*/ @RoRNat
publicint getPageNum(){ }* B qi7E>
return(count - 1) / num + 1; 17n+4J]
} iA%'
;V
Xv-1PY':pA
/** "doU.U&u
* 获得本页的开始编号,为 (p-1)*num+1 5&-j{J0iV
*/ 0x]OF8=J
publicint getStart(){ ph8Jn+|E
return(p - 1) * num + 1; 0[2BY]`Z.
} RI5g+Du?
\=EY@*=
/** e\^g|60f_
* @return Returns the results. @`IXu$Wm(
*/ u8<&F`7j
publicList<E> getResults(){ 2Z/][?Jj{
return results; /jjW/lr
} #7-kL7 MK]
yUD_w
public void setResults(List<E> results){ k%Ma4_Z
this.results = results; r sX$fU8
} SLQ\Y%F
-TK|Y"
public String toString(){ B@"SOX
StringBuilder buff = new StringBuilder hs!UX=x|
I=4Xv<F
(); wVvqw/j*f
buff.append("{"); b(.-~c('
buff.append("count:").append(count); 93E,
buff.append(",p:").append(p); IdV,%d{
buff.append(",nump:").append(num); (C-,ljY
buff.append(",results:").append [):{5hMA
J{Y6fHFi
(results); &\J?[>EJ.
buff.append("}"); wMH[QYb<*
return buff.toString(); Z/89&Uy`h
} &Q-[;
yCF"Z/.
} `y8
?=
8iMF 8\
NLcO{