Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 3Q6#m3AWY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 +4Ra N`I
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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 +w/o
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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 TMs\#
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分页支持类: N($]))~3&
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java代码: ~nlY8B(
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package com.javaeye.common.util; 2Ki/K(
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import java.util.List; +d15a%^`
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publicclass PaginationSupport { r
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publicfinalstaticint PAGESIZE = 30; hWJc
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privateint pageSize = PAGESIZE; y->iv%
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privateList items; p*,mwKN:
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privateint totalCount; :zoX
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privateint[] indexes = newint[0]; kDQXPp
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privateint startIndex = 0; cPYQ<Y=
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public PaginationSupport(List items, int YWdvL3Bgk,
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totalCount){ _!D$Aj
setPageSize(PAGESIZE); ]QQ"7_+
setTotalCount(totalCount); P&VI2k
setItems(items); W525:h52{
setStartIndex(0); "/=xu|
} wOP}SMn
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public PaginationSupport(List items, int R&A.F+Zgt
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totalCount, int startIndex){ j.*}W4`Q_
setPageSize(PAGESIZE); 3{=4q
setTotalCount(totalCount); UK/k?0
setItems(items); <Th.}=
setStartIndex(startIndex); YVi]f2F%
} Zuf&maa S
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public PaginationSupport(List items, int :gn!3P}p?
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totalCount, int pageSize, int startIndex){ ty
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setPageSize(pageSize); c`cPGEv
setTotalCount(totalCount); >?tpGEZ\
setItems(items); (H7q [UG|
setStartIndex(startIndex); XR(kR{yo
} YDJc@*D
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publicList getItems(){ .'M]cN~
return items;
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} n&^Rs)%v
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publicvoid setItems(List items){ 2_p/1Rs
this.items = items; 0FBifK
} }N NyUwFa
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publicint getPageSize(){ *!r8HV/<
return pageSize; 9j/B3CjW
} O\?ei+(H7
EW)]75o{QF
publicvoid setPageSize(int pageSize){ rHznXME$wZ
this.pageSize = pageSize; hk(^?Fp
} /@K?W=w4
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publicint getTotalCount(){ xM(
return totalCount; |
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} =6'A8d
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publicvoid setTotalCount(int totalCount){ z
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if(totalCount > 0){ D*b>
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this.totalCount = totalCount; -H{{
int count = totalCount / ),86Y:^4
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pageSize; `KZ}smMA
if(totalCount % pageSize > 0) vjW S35i
count++; H|P.q{(G
indexes = newint[count]; ) E5ax~
for(int i = 0; i < count; i++){ bR.T94-8y
indexes = pageSize * 'n\ZmG{
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} 6d,"GT
}else{ :t(}h!7
this.totalCount = 0; R6ywc"xE
} :E.mU{
} L_/.b%0)
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publicint[] getIndexes(){ {oO!v}]
return indexes; mIOx)`$
} Rzz*[H
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publicvoid setIndexes(int[] indexes){ 3?C$Tl2G8
this.indexes = indexes; N52N ^X>
} lgU7jn
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publicint getStartIndex(){ 'EXp[*
return startIndex; R5Ti|k.~Y"
} T2k5\r8
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publicvoid setStartIndex(int startIndex){ h|wyvYKZ
if(totalCount <= 0) yQ\c<z^e
this.startIndex = 0; `CW =*uBH
elseif(startIndex >= totalCount) Hh,\>= ':
this.startIndex = indexes (xMAo;s_
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[indexes.length - 1]; ,w
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elseif(startIndex < 0) wqJH
this.startIndex = 0; zvE]4}VL?
else{ 8g$pfHt|e
this.startIndex = indexes w<>B4m\
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[startIndex / pageSize]; 1_%3cN.
} y "gYv
} k |M
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publicint getNextIndex(){ }{HlY?S
int nextIndex = getStartIndex() + ^dRB(E}|)
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pageSize; _HGbR/
if(nextIndex >= totalCount)
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return getStartIndex(); h
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else uPt({H
return nextIndex; Ee^2stc-
} YDO#Q= q%
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publicint getPreviousIndex(){ 4;y*y tY*
int previousIndex = getStartIndex() - QrDI$p7;'
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pageSize; :(E.sT"R
if(previousIndex < 0) b@"#A8M
return0; fn;`V it#
else uL`_Sdjw
return previousIndex; ~}+F$&
} ;5MI8
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} 6;Wns'
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抽象业务类 3vepJ)D (
java代码: Z0 @P1
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/** bW-9YXj%
* Created on 2005-7-12 }Ox5,S}ra
*/ B 'SLyf
package com.javaeye.common.business; !59u z4
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import java.io.Serializable; &?"E"GH
import java.util.List; +~Wg@
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import org.hibernate.Criteria; ;auT!a~a#
import org.hibernate.HibernateException; Vq4g#PcG
import org.hibernate.Session; z>}H[0[#
import org.hibernate.criterion.DetachedCriteria; >{R+j4%
import org.hibernate.criterion.Projections; j2^Vz{
import *5m4j=-
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org.springframework.orm.hibernate3.HibernateCallback; M-7^\wXTA
import F}MjZZj(U=
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org.springframework.orm.hibernate3.support.HibernateDaoS C)hS^D:
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upport; >=O5=\`
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import com.javaeye.common.util.PaginationSupport; P.#@1_:gC
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public abstract class AbstractManager extends Qv1<)&Ft<
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HibernateDaoSupport { r|av|7R
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privateboolean cacheQueries = false; n~_;tO
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privateString queryCacheRegion; FIu|eW+<l
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publicvoid setCacheQueries(boolean d
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cacheQueries){ Jo'~oZ$
this.cacheQueries = cacheQueries; _D"V^4^yqu
} sU7fVke1
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publicvoid setQueryCacheRegion(String :6TLT-B
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queryCacheRegion){ %1\~OnT
this.queryCacheRegion = o#uhPUZ
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queryCacheRegion; Fe1^9ja
} *)bh6b=7
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publicvoid save(finalObject entity){ I+eKuWB
getHibernateTemplate().save(entity); k5g vo
} A= 96N@m6
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publicvoid persist(finalObject entity){ W#9A6ir>
getHibernateTemplate().save(entity); blx"WVqo
} zX8'OoEH*9
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publicvoid update(finalObject entity){ W4#E&8g%
getHibernateTemplate().update(entity); Ex<@:
} b
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publicvoid delete(finalObject entity){ v8U&{pD,
getHibernateTemplate().delete(entity); Owz>g4l
r
} |U`ASo
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publicObject load(finalClass entity, Il]p >B
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finalSerializable id){ L-`?=- 9`
return getHibernateTemplate().load V~7Oa2'#B
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(entity, id); 0ZJrK\K;
} ^!6T,7B B
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publicObject get(finalClass entity, "lA8CA
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finalSerializable id){ ]#;u]
return getHibernateTemplate().get _iH:>2p 5R
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(entity, id); *5mJA -[B+
} ~pw%p77)
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publicList findAll(finalClass entity){ ]Wn=Oc{F
return getHibernateTemplate().find("from 3oC^"723
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" + entity.getName()); ]RuH6d2d|
} Of;$
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publicList findByNamedQuery(finalString )U+&XjK
& &:ZY4`
namedQuery){ i9^m;Y)^I
return getHibernateTemplate k&= iye(
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().findByNamedQuery(namedQuery); iza.' Mm~
} TUi<
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publicList findByNamedQuery(finalString query, uDMyO<\
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finalObject parameter){ )QB9zl:
return getHibernateTemplate gcF V$
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().findByNamedQuery(query, parameter); W;T(q~XK
} 4EFP*7X
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publicList findByNamedQuery(finalString query, $ItPUYi";
}/VSIS@Z
finalObject[] parameters){ *}Gu'EU
return getHibernateTemplate eB5<N?;s
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().findByNamedQuery(query, parameters); 3&Fqd
} W C3b_ia
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publicList find(finalString query){ ~c'R7E&Bfa
return getHibernateTemplate().find h<FEe~
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(query); ?sbM= oo
} g&L $5
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publicList find(finalString query, finalObject UY&DXIP M
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parameter){ -P$E)5?^
return getHibernateTemplate().find o88Dz}a
)q'~<QxI\
(query, parameter); ?]2OT5@&s
} Bk8 '*O/)
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public PaginationSupport findPageByCriteria AK5$>Pkvk
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(final DetachedCriteria detachedCriteria){ d5tpw$A
return findPageByCriteria
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :]-? l4(%
} ZUUfn~ORc
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public PaginationSupport findPageByCriteria dIDs~
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(final DetachedCriteria detachedCriteria, finalint P7p'j
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startIndex){ _Rnq5y
return findPageByCriteria parC~)b_
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(detachedCriteria, PaginationSupport.PAGESIZE, m7~[f7U
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startIndex); o*1t)HL <
} %]@K}!)2
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public PaginationSupport findPageByCriteria ;t}ux
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(final DetachedCriteria detachedCriteria, finalint Y4dTv<=K@i
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pageSize, &tw
finalint startIndex){ },5_h0
return(PaginationSupport) nW
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getHibernateTemplate().execute(new HibernateCallback(){ rKys:is
publicObject doInHibernate ps6c>AN`A&
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(Session session)throws HibernateException { DeTZl+qm1E
Criteria criteria = $W;IW$
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detachedCriteria.getExecutableCriteria(session); y3!=0uPf
int totalCount = E5 0$y:
#/9(^6f:
((Integer) criteria.setProjection(Projections.rowCount x9NLJI21/
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()).uniqueResult()).intValue(); x 1"ikp}
criteria.setProjection <~Tlx:
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(null); \HOOWaapN
List items = t9()?6H\
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criteria.setFirstResult(startIndex).setMaxResults :=tPC A=
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(pageSize).list(); (UV+/[,
PaginationSupport ps = (&$|R\W.
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new PaginationSupport(items, totalCount, pageSize, HYPFe|t/
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startIndex); f. =4p^
return ps;
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} ^q,KRut
}, true); 9Yowz]')
} OI.2C F
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public List findAllByCriteria(final Rh%/xG#k
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DetachedCriteria detachedCriteria){ L&'0d$Tg8
return(List) getHibernateTemplate K`FgU7g{
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().execute(new HibernateCallback(){ morI'6N
publicObject doInHibernate z[S,hD\w
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(Session session)throws HibernateException { =D4EPfQn1
Criteria criteria = |7/B20
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detachedCriteria.getExecutableCriteria(session); vmOXB#7W
return criteria.list(); B<[;rk
} Prhq ~oI4
}, true); FV$= l
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} r[Q$w>
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public int getCountByCriteria(final =tH+e7it
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DetachedCriteria detachedCriteria){ im+2)9f
Integer count = (Integer) ok\+$+$ju
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getHibernateTemplate().execute(new HibernateCallback(){ #fGb M!3p
publicObject doInHibernate s80_e
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(Session session)throws HibernateException { #K!Df%,<
Criteria criteria = \MtiLaI"
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detachedCriteria.getExecutableCriteria(session); ,0 &lag
return 9'toj%XQ
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criteria.setProjection(Projections.rowCount G>mgoN
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()).uniqueResult(); B@zJ\Ir[
}
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}, true); @?B=8VHR
return count.intValue(); HB`pK'gz
} #]eXI
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} DJQ]NY|
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用户在web层构造查询条件detachedCriteria,和可选的 50DPzn
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (C-z8R
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PaginationSupport的实例ps。 Bd
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ps.getItems()得到已分页好的结果集 p fBO5Ys
ps.getIndexes()得到分页索引的数组 ==XP}w)m
ps.getTotalCount()得到总结果数 ^CK)q2K>[
ps.getStartIndex()当前分页索引 k9Sqp:l,
ps.getNextIndex()下一页索引 6ZG)`u".("
ps.getPreviousIndex()上一页索引 Tc88U8Gc
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 HQ
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !%u#J:z2
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一下代码重构了。 M)J *Df0@
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我把原本我的做法也提供出来供大家讨论吧: lTB!yF.r|
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首先,为了实现分页查询,我封装了一个Page类: %UQ{'JW?K
java代码: \9}5}X_x.
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/*Created on 2005-4-14*/ _#gsR"FZ$
package org.flyware.util.page; *SY4lqN
4 P;O8KA5y
/** x>J3tp$2
* @author Joa =P#!>*\ar
* @}?D<O8#"#
*/ $dnHUBB
publicclass Page { pMquu&Td
)j6>b-H
/** imply if the page has previous page */ <kSaSW
privateboolean hasPrePage; - X_w&
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/** imply if the page has next page */ 2wBU@T1
privateboolean hasNextPage; -*lP1Nbp
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/** the number of every page */ >Y+KL
privateint everyPage; ~1'468
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/** the total page number */ DXz8C -
privateint totalPage; ^d9raYE`'
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!
/** the number of current page */ M([H\^\:
privateint currentPage; I.u,f:Fl'
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/** the begin index of the records by the current 4LjSDgA
x!~OK::o8
query */ \Ep/'Tj&
privateint beginIndex; M0zD)@
@L!#i*> 9
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/** The default constructor */ sOxdq"E
public Page(){ [U(&Ae0V>
&iOtw0E
} I|IlFu?O=
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/** construct the page by everyPage 0:Y`#0qK
* @param everyPage _<a)\UR
* */ OZ;E&IL
public Page(int everyPage){ >ij4z
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this.everyPage = everyPage; W>s'4C`
} *wB-lg7%
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/** The whole constructor */ ^X;Xti
public Page(boolean hasPrePage, boolean hasNextPage, 1ysLZ;K
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int everyPage, int totalPage, !;aC9VhSU
int currentPage, int beginIndex){ !(_xu{(DL
this.hasPrePage = hasPrePage; U\8#Qvghf
this.hasNextPage = hasNextPage; A4Q)YY9~
this.everyPage = everyPage; C9g~l}=$&
this.totalPage = totalPage; [a)~Dui0@\
this.currentPage = currentPage; O4PdN?
this.beginIndex = beginIndex; :5K~/=6x
} [9U srpYi
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/** /-YlC(kL
* @return }Q=se[((
* Returns the beginIndex. _Q}RElA
*/ . 02(O
publicint getBeginIndex(){ /9+A97{
return beginIndex; SxW}Z_8x
} :$cSQ(q9a
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/** 9h38`*Im;
* @param beginIndex YeExjC
* The beginIndex to set. @oqi@&L'C
*/ 4fu\3A&
publicvoid setBeginIndex(int beginIndex){ 2V2x,!
this.beginIndex = beginIndex; uU ?37V
} PDq}Tq
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/** ?J@?,rZQ^V
* @return ~2A$R'x b
* Returns the currentPage. zj$_iB`9
*/ ilRm}lU|x
publicint getCurrentPage(){ VVQ74b
return currentPage; X\^& nLa
} 1[/$ZYk:
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/** p]V-<
* @param currentPage [5p7@6:$u
* The currentPage to set. `/wq3+ ?
*/ >uchF8)e|
publicvoid setCurrentPage(int currentPage){ 4'{hI;&a&
this.currentPage = currentPage; gLxT6v5wk.
} f0mH|tI`
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/** $XQ;~i
* @return AeY$.b
* Returns the everyPage. }Uwkef.Q
*/ D=82$$
publicint getEveryPage(){ >0<KkBH
return everyPage; (|36!-(iK
} ^!o1l-Y^gr
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/** Ql:
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* @param everyPage 6N%L8Q
* The everyPage to set. ~^%0V<*-}
*/ "doU.U&u
publicvoid setEveryPage(int everyPage){ .e FOfV)
this.everyPage = everyPage; |auX*hb9
} vNK`Y|u@
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/** w`.T/
* @return ER;lkF`RF
* Returns the hasNextPage. *< $c
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*/ ~`~%(DA=
publicboolean getHasNextPage(){ u8<&F`7j
return hasNextPage; PQU3s$
} DYT@BiW{
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/** 5D]30
* @param hasNextPage #Cg}!38
* The hasNextPage to set. '&.)T2Kw
*/ GCP{Z]u
publicvoid setHasNextPage(boolean hasNextPage){ oeu|/\+HW
this.hasNextPage = hasNextPage; wr3_Bf3]
} >/!7i3Ow-
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/** b"R, p=M
* @return g+ >=C
* Returns the hasPrePage. l50|`
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*/ nJtEUVMt
publicboolean getHasPrePage(){ [l8V<*x%S9
return hasPrePage; IdV,%d{
} (C-,ljY
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/** OYszW]UMg
* @param hasPrePage p4m^ ~e
* The hasPrePage to set. h*;g0QBkl
*/ wMH[QYb<*
publicvoid setHasPrePage(boolean hasPrePage){ {h/OnBwG
this.hasPrePage = hasPrePage; B\=SAi
} H
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/** a,/M'^YyN
* @return Returns the totalPage. a)3O? Y
* NLcO{
*/ 5y1or
publicint getTotalPage(){
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return totalPage; ^%\)Xi
} W]@gQ(Ef
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/** ${A5-
* @param totalPage fOa6,
* The totalPage to set. T"L0Iy!k;
*/ >.DF"]XM
publicvoid setTotalPage(int totalPage){ 0Y2\n-`z
this.totalPage = totalPage; 5x*5|8
} ! (2-(LgA
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} Uj4Lu
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 |HrM_h<X
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个PageUtil,负责对Page对象进行构造: 7%{R#$F
java代码: EKqi+T^=F
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/*Created on 2005-4-14*/ 7IA3q{P
package org.flyware.util.page; uz ]E_&2
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import org.apache.commons.logging.Log; ?k
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import org.apache.commons.logging.LogFactory; ;*y|8od
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/** 'Pf_5q
* @author Joa VBu8}}Ql
* d!`lsh@tF
*/ uA~YRKer
publicclass PageUtil { _e6a8
}0$mn)*k
privatestaticfinal Log logger = LogFactory.getLog PKi_Zh.D
I^WIa"u_
(PageUtil.class); /@Ez" ?V2
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/** tC2N>C[N
* Use the origin page to create a new page p?;-!TUv
* @param page 6G'<[gL
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* @param totalRecords Y5HfN[u^7
* @return I[ai:
*/ ,!`SY)
publicstatic Page createPage(Page page, int \@i=)dA
x;Gz6|
totalRecords){ !/947Rn
return createPage(page.getEveryPage(), x"vwWJNQ
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page.getCurrentPage(), totalRecords); ,E&Bn8L~O
} YZibi
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/** F<5nGx cC
* the basic page utils not including exception aM), M]m[
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handler ,*dzJT$k
* @param everyPage ^\:yf.k
* @param currentPage r=qLaPG
* @param totalRecords 8zZSp
* @return page *wwhZe4V
*/ B
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publicstatic Page createPage(int everyPage, int co/7l sW
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currentPage, int totalRecords){ h4Ia>^@
everyPage = getEveryPage(everyPage); nX._EC
currentPage = getCurrentPage(currentPage); 3%^z ?_
int beginIndex = getBeginIndex(everyPage, !h>D;k6 e
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currentPage); =<{ RX8
int totalPage = getTotalPage(everyPage, >!}`%pk(
\X&
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totalRecords); 0 O~p7D
boolean hasNextPage = hasNextPage(currentPage, @rO4y`
< A?<N?%o
totalPage); 5 [4Z=RP
boolean hasPrePage = hasPrePage(currentPage); |) Pi6Y
o 7G> y#Y
returnnew Page(hasPrePage, hasNextPage, '&by3y5w-3
everyPage, totalPage, #.<V^
currentPage, ANMYX18M
2zK"*7b?
beginIndex); s*Ih_Ag=:
} S5_t1wqBJ
Uki9/QiX>
privatestaticint getEveryPage(int everyPage){ F}U5d^!2
return everyPage == 0 ? 10 : everyPage; {B0h+. C
} `5'2Hg+
.+E#q&=
privatestaticint getCurrentPage(int currentPage){ LmQ/#Gx
return currentPage == 0 ? 1 : currentPage; K;U39ofW
} xMI+5b8
K)S;:MLG=
privatestaticint getBeginIndex(int everyPage, int EvE,Dm?h
)`8pd 7<.
currentPage){ \cQ .|S
return(currentPage - 1) * everyPage; 5)'P'kVi7.
} 3bs4mCq
F
Z!J
privatestaticint getTotalPage(int everyPage, int h1+hds+
1$ML #5+,
totalRecords){ >qR~'$,$
int totalPage = 0; hVP
IHQt
jxw_*^w"
if(totalRecords % everyPage == 0) }q!_!q,@
totalPage = totalRecords / everyPage; #SkX@sl@
else 9vI]LfP
totalPage = totalRecords / everyPage + 1 ; T&xt`|
Dag`>|my
return totalPage; jtKn3m7 +p
} YQgNv` l}
;=jr0\| e
privatestaticboolean hasPrePage(int currentPage){ 5H lWfD
return currentPage == 1 ? false : true; )%Ru#}1X6
} 4tXSYHd3
[pgZbOIN37
privatestaticboolean hasNextPage(int currentPage, [VSU"AJY
mm[SBiFO\
int totalPage){ DQJG,?e{
return currentPage == totalPage || totalPage == 0a2@b"l
nl1-kB)$e|
0 ? false : true; ^#e~g/
} V 0{tap}
?Zz'|.l@
z`$J_Cj Y
} K:5eek
h`5)2n+ P
*'R#4@wmP
4MW ]EQ-
PRs@zkO
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。 Zzj0\?Ul
'Qn~H[$/p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 D>sYPrf
RuAlB*
做法如下: ijUzC>O+q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ]hTb@.
qpqokK
的信息,和一个结果集List: Bjj<\8^M
java代码: +S~.c;EK
Cg!^S(U4
cd. brM
/*Created on 2005-6-13*/ K7`YJp`i
package com.adt.bo; .36^[Jsz":
3Wx,oq;4-
import java.util.List; z?ucIsbR
}zMf7<C
import org.flyware.util.page.Page; 8SmjZpQ?
j9y3hQ+q
/** -50AX1h31:
* @author Joa :tGYs8UK
*/ 0 bSA_
publicclass Result { >+9JD%]x]
&%F@O<:
private Page page; J7&DR^.Sw
U/w. M_S
private List content; ~&VN_;j_
``QHG&$/
/** 3$p#;a:=n
* The default constructor [Ot,q/hBJ
*/ SUdm 0y
public Result(){ _ PWj(});
super(); ]~c+'E`
} f3PMVf:<
FY#!N
L
/** $Ua56Y
* The constructor using fields e~\QE0Oe :
* R>)MiHcCg
* @param page WeT* C
* @param content |. C1|J'Z
*/ [*Ju3
public Result(Page page, List content){ l";'6;g
this.page = page; N:BL=}V
this.content = content; TZB+lj1
} /iM$Tb5
e<=;i" |
/** cCdX0@hY
* @return Returns the content. )pgrl
*/ VcgBLkIF
publicList getContent(){ zCe/Kukvy
return content; "S!3m9_#
} T] | d5E
xHkxc}h
/** \7 a4uc
* @return Returns the page. Plo ,XU
*/ zQ8!rCkg4
public Page getPage(){ 3C^1frF
return page; :Ml7G
} gA^q^>7
wD9a#AgEd
/** %%}A|,
* @param content zICI_*~
* The content to set. 9`Q@'(m
*/ ]n
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public void setContent(List content){ t9
F=^)s
this.content = content; Dz&+PES_k
} z;3NiY
O.+9,4A(
/** 8<&EvOk
* @param page !~ rt:Z
* The page to set. LI
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*/ #@//7Bf%
publicvoid setPage(Page page){ r/r:oXK
this.page = page; /9 hR
} E_:QSy5G
} I$jvXl=$
oyeG$mpg
W|UtY`1
y\PxR708
Re[:qLa]
2. 编写业务逻辑接口,并实现它(UserManager, *|RS*ABte
HD-Erop
UserManagerImpl) AtHS@p
java代码: +x1/-J8_sg
q)I|2~Q c^
(JZ".En#X
/*Created on 2005-7-15*/ \"^%90F
package com.adt.service; FC>d_=V
><Z'D
import net.sf.hibernate.HibernateException; f&I7,"v
`E>vG-9
import org.flyware.util.page.Page; ZF{~ih*^u
lOerrP6f(
import com.adt.bo.Result; Fdt}..H%
C1B'#F9EO
/** v\A.Tyy
* @author Joa []p"3i
*/ z+VV}:Q
publicinterface UserManager { HeIS;gfUY
Q,e*#oK3$
public Result listUser(Page page)throws 2p< Aj!
($d4:Ww
HibernateException; 2*OxA%QELM
[)|+F
wJ
} >)c9|e=8
=ApY9`
S/Oxr%H
ZBM!MSf:
MCy~@)-IN
java代码: MOHHZApt
!nw[
n0fR u`SNV
/*Created on 2005-7-15*/ %z)EO9vtr
package com.adt.service.impl; 8(lCi$
m&El)
import java.util.List; 5~}!@yzc
+/N1_
import net.sf.hibernate.HibernateException; _s>^?x}
kk_zVrQ<
import org.flyware.util.page.Page; 0dt"ZSm
import org.flyware.util.page.PageUtil; 2d&^Sp&11
I'InZ0J2
import com.adt.bo.Result; QJXdb]Y^;
import com.adt.dao.UserDAO; pxplWP,
import com.adt.exception.ObjectNotFoundException; RVF F6N^
import com.adt.service.UserManager; vLn> 4SK
0wvU?z%WK
/** O/9fuEF
* @author Joa ` :5,e/5,
*/ 0yQe5i}
publicclass UserManagerImpl implements UserManager { !5.v'K'
F#1kZ@nq
private UserDAO userDAO; Qj!d ^8
Q8Te'1Ln!
/** t2.juoI(
* @param userDAO The userDAO to set. }td6fj_{
*/ d*9j77C ]
publicvoid setUserDAO(UserDAO userDAO){ /(zB0TEd
this.userDAO = userDAO; e"_"vbk
} (Y;'[.
eT\p-4b
/* (non-Javadoc) J/7u7_
* @see com.adt.service.UserManager#listUser 3@HIpQM3
v=Mz I#0L
(org.flyware.util.page.Page) 0UjyMEiK
*/ *a4
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public Result listUser(Page page)throws Y3M','H([
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HibernateException, ObjectNotFoundException { 6jtTT%>y
int totalRecords = userDAO.getUserCount(); _z%\'(l+
if(totalRecords == 0) 4Q&mC"
throw new ObjectNotFoundException P^;WB*V
Is
kSX
("userNotExist"); 3G(skphE
page = PageUtil.createPage(page, totalRecords); d<?X3&J
List users = userDAO.getUserByPage(page); Tvrc%L(]
returnnew Result(page, users); c}\
d5R_L
} 6\mC$: F
c8\g"T
} d-i&k(M
/0!$p[cjm
|vT=Nnu
jL2MW(d^Q
!$XO
U'n
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 GiFf0c
9
:n`0)g[(
询,接下来编写UserDAO的代码: I')x]edU
3. UserDAO 和 UserDAOImpl: nu(eLUU
java代码: rZ 6@b
EyPy*_A
P^n{Y~P=Q
/*Created on 2005-7-15*/ "pl[(rc+u
package com.adt.dao; yT 2vO_rH
s'2y%E#
import java.util.List; \O,j}O'
7TR'zW2W
import org.flyware.util.page.Page; tUn&z?7bF
v@]6<e$
import net.sf.hibernate.HibernateException; LsUFz_
C`z;,!58%
/** W>VAbm
* @author Joa F^[M
*/ e4 ?<GT
publicinterface UserDAO extends BaseDAO { L5TNsLx (
}]Qmt5'NI
publicList getUserByName(String name)throws ~F=#}6kg_
[v~Uy$d\
HibernateException; JO]`LF]
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publicint getUserCount()throws HibernateException; J>/Ci\OB
cRjL3
publicList getUserByPage(Page page)throws P=}H1#
m]
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HibernateException; nqUH6(
'aLPTVM^
} k-;.0!D^
`*|LI
P]{B^,E
Y^T-A}?`
^ON-#
java代码: <7@mg/T
tOu90gu
M^0w/
/*Created on 2005-7-15*/ _D!M
nTK
package com.adt.dao.impl; Sj,4=a
fbi H
import java.util.List; ?Aj\1y4L1
}6yxt9
import org.flyware.util.page.Page; Xd90n>4S
D>,$c
import net.sf.hibernate.HibernateException; 6:8EZ'y
import net.sf.hibernate.Query; *8pe<:A#p
6~>^pkV
import com.adt.dao.UserDAO; KE }o
9F-ViDI.
/** \emT:Frb
* @author Joa UEx(~>
*/ tF{{cd
public class UserDAOImpl extends BaseDAOHibernateImpl >Rx8 0
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implements UserDAO { ~2;&pZ$
bw<~R2[
/* (non-Javadoc) ]JhDRJ\
* @see com.adt.dao.UserDAO#getUserByName NzwGc+\7}
=6L:Ix
(java.lang.String) kM6
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*/ Q_UCF'f;}
publicList getUserByName(String name)throws l7=$4As/hI
c +"O\j'
HibernateException { ^ mQ;CMV
String querySentence = "FROM user in class RBHqLg(
;$k?&nhY
com.adt.po.User WHERE user.name=:name"; CU}
q&6h
Query query = getSession().createQuery *$*nY [/5
hx2!YNx !
(querySentence); U)T/.L{0i
query.setParameter("name", name); \?p9qR;"4
return query.list(); Nys'4kx7
} o
i,g
v/4X[6(
/* (non-Javadoc) PgGrk5;
* @see com.adt.dao.UserDAO#getUserCount() HY%6eUhj
*/ 'J&@jp
publicint getUserCount()throws HibernateException { U:T5o]P<
int count = 0; &6~ncQWu
String querySentence = "SELECT count(*) FROM [1[[$ Dr
8B% O%*5`
user in class com.adt.po.User"; e[|p0 ,Q
Query query = getSession().createQuery q>Ar.5&M_
b;t}7.V'%
(querySentence); ix_$Ok
count = ((Integer)query.iterate().next 2EI m
R4K eUn"
()).intValue(); )H=[NB6J8
return count; [{d[f|
} wft:eQ
VN55!l'OV
/* (non-Javadoc) Lqf#,J
* @see com.adt.dao.UserDAO#getUserByPage d}6AHS[
Q Kuc21
(org.flyware.util.page.Page) ybuSqFy`$
*/ 3M>FU4Ug2
publicList getUserByPage(Page page)throws c]/O^/
&VBD2_T
HibernateException { <:_]Yl
String querySentence = "FROM user in class 28ov+s~1+-
p|O-I&Xd
com.adt.po.User"; XP
Iu]F
Query query = getSession().createQuery ,"lBS?
3=eGS
(querySentence); GE| ^ryh
query.setFirstResult(page.getBeginIndex()) 8Jly!=Qm5
.setMaxResults(page.getEveryPage()); ',xsUgk
return query.list(); )]e d;V
} r^Rcjyc1
&rtz&}ZB;
}
Dg2#Gv0B
AFF>r#e
9.w3VF_C
W$ d{
'_yk_[/
至此,一个完整的分页程序完成。前台的只需要调用 C
Wl95g
_ZE$\5>-
userManager.listUser(page)即可得到一个Page对象和结果集对象 $hY]EB
l`w|o
的综合体,而传入的参数page对象则可以由前台传入,如果用 ->#@rF:S
E/Gs',Y
webwork,甚至可以直接在配置文件中指定。 0:(dl@I)@
MxvxY,~{0
下面给出一个webwork调用示例: e+[J[<8
java代码:
8 $*cfOC
6"c!tJc7j
vkauX:M
/*Created on 2005-6-17*/ 4lo}-@j
package com.adt.action.user; q,h.W JI
v lnUN
import java.util.List; n[p9$W`
2|H'j~
import org.apache.commons.logging.Log; W&q5cz
import org.apache.commons.logging.LogFactory; `uJ l<kHI
import org.flyware.util.page.Page; \(7# N<-
a9q?9X
import com.adt.bo.Result; aRb:.\ \zc
import com.adt.service.UserService; eOnl
sx/
import com.opensymphony.xwork.Action; *gMP_I
lNnbd?D8
/** E$zq8-p|
* @author Joa we).8%)'
*/ Fm+)mmJP
publicclass ListUser implementsAction{ :zy'hu;
|N3CoB
privatestaticfinal Log logger = LogFactory.getLog lkJ#$Ik&
3ncvM>~g
(ListUser.class); c!FjHlAnP
-(,6w?
private UserService userService; iKTU28x
YVV $g-D}
private Page page; P\4o4MF@K
R$,iDv.jI
privateList users; lcJumV=%>
tg`!svL!
/* :1
* (non-Javadoc) $GKm`I"
* yXQ;LQ;
* @see com.opensymphony.xwork.Action#execute() B{i;+[ase
*/ ?mUu(D:7D
publicString execute()throwsException{ dWWkO03|
Result result = userService.listUser(page); S#z8H+'
page = result.getPage(); ^\9G{}VY
users = result.getContent(); ,TA[el%#
return SUCCESS; H<Taf%JT
} I%WK*AORM
~ab_+%
/** e-av@a3
* @return Returns the page. Xr;noV-X
*/ 85~h+Q;
public Page getPage(){ 6df&B
.gg
return page; C)kQi2T
} 7anpz%
< tq9
/** 0PbIWy'
* @return Returns the users. i^KYZ4/%
*/ vw6FvE`lC
publicList getUsers(){ BC[d={_-
return users; Vb#@o) z
} F<WX\q
. +?lID
/** v%Q7 \X(
* @param page d9( Sj?
* The page to set. dz9-+C{m
*/ LK5H~FK
publicvoid setPage(Page page){ QYGxr+D
this.page = page; 3]'z8i({7Y
} B.WkHY%/
R/YL1s
/** qnRzs
* @param users .NC}TFN|
* The users to set. C(Y6t1
*/ +yI^<BH
publicvoid setUsers(List users){ F'*&-l
this.users = users; =*U24B*U93
} L,/i%-J3c
21 j+c{O
/** h;M2ylOu.
* @param userService t1^96@m^
* The userService to set. 0E[Se|!
*/ A UV$ S2
publicvoid setUserService(UserService userService){ Nf'9]I
this.userService = userService; B6oAW ,3
} S7Fxb+{6D
} 0wcWDE
9
bb/MnhB
b2%[9)"I.
,oe{@z{*@
'wt|buu-H
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, 6iWuBsal
VA.1JBQ
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 RGLqn{<