Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6[~_;0
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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 {
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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 p%ZOLoc)Y
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分页支持类: /JbO $A
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java代码: ]7DS>%mY(
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package com.javaeye.common.util; gO%oA} !i
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import java.util.List; %s*F~E
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publicclass PaginationSupport { $3)Z>p
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publicfinalstaticint PAGESIZE = 30; -ztgirU
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privateint pageSize = PAGESIZE; O~DdMW
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privateList items; h"ZR`?h
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privateint totalCount; @tzL4hy%^j
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privateint[] indexes = newint[0]; Ce`#J6lT
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privateint startIndex = 0; )y"8Bx=x4
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public PaginationSupport(List items, int AXT(D@sI=
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totalCount){ b;jr;I
setPageSize(PAGESIZE); hywy(b3
setTotalCount(totalCount); )PCh;P0C
setItems(items); }=$>w@mJ
setStartIndex(0); WlW7b.2.
} Hkzx(yTi
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public PaginationSupport(List items, int 88g|(k/
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totalCount, int startIndex){ Cc&SHG*R
setPageSize(PAGESIZE); Gc*p%2c
setTotalCount(totalCount); |{V@t1`
setItems(items); 7&w$@zs87
setStartIndex(startIndex); /5N`Euw
} p,K!'\
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public PaginationSupport(List items, int B0$ge"FK9
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totalCount, int pageSize, int startIndex){ @ebSM#F?
setPageSize(pageSize); uq\[^
setTotalCount(totalCount); Mem1X rBH
setItems(items); e]zd6{g[m
setStartIndex(startIndex); ~ya@ YP]';
} EK2mJCC|
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publicList getItems(){ 'y%*W:O
return items; jeWI<ms
} 5fY7[{2
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publicvoid setItems(List items){ 'LMMo4o3
this.items = items; 4 zhg#
} <*[D30<
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publicint getPageSize(){ ^{g('BQx
return pageSize; "Ta"5XW
} *o6hDhg
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publicvoid setPageSize(int pageSize){ BFvRU5&Sz
this.pageSize = pageSize; Pq3m(+gf
} @FaK/lKK
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publicint getTotalCount(){ 'mYUAVmSC#
return totalCount; F2!]T =
} ;!pSYcT,
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publicvoid setTotalCount(int totalCount){ )MeeF-Ad6
if(totalCount > 0){ O#n=mJ
this.totalCount = totalCount; dM)x|b3z
int count = totalCount / ;5&=I|xqe
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pageSize; Z3 O_K
if(totalCount % pageSize > 0) Lq]t6o]
count++; LO@o`JF
indexes = newint[count]; bzyy;`;6Q~
for(int i = 0; i < count; i++){ 6<Txkk
indexes = pageSize * H: ]'r5sw
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i; >)6k)$x%%
} su0q 2.
}else{ o]TKL'gW
this.totalCount = 0; 0S#T}ITm4Z
} PrvV]#O*
} X?++I4\
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publicint[] getIndexes(){ ]o($No
return indexes; a\*_b2 ^n
} G'{*guYU
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publicvoid setIndexes(int[] indexes){ 1 Szv4
this.indexes = indexes; &f-x+y
} vVf%wei^#
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publicint getStartIndex(){ MQMc=Z4d
return startIndex; ,A[NcFdCB
} W.nr&yiQ
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publicvoid setStartIndex(int startIndex){ |-`-zo4z
if(totalCount <= 0) E_-g<Cw
this.startIndex = 0; z<OfSS_]R
elseif(startIndex >= totalCount) GQ6~Si2
this.startIndex = indexes #'8'5b
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[indexes.length - 1]; j7yUya&
elseif(startIndex < 0) Y3g<%6
this.startIndex = 0; TEQs9-Uy
else{ ?fX`z(Z
this.startIndex = indexes qnJs,"sn
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[startIndex / pageSize]; kE854Ej
} @*=eqO
} (05a9
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publicint getNextIndex(){ [z,6 K=
int nextIndex = getStartIndex() + .TO#\!KBv
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pageSize; < Y)A ez
if(nextIndex >= totalCount) l0lvca=;
return getStartIndex(); /)<Xoa
else ~(}nd
return nextIndex; G]T&{3g-.
} l*b0uF
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publicint getPreviousIndex(){ B8>3GZi
int previousIndex = getStartIndex() - jE!?;} P1
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pageSize; 4^7*R
if(previousIndex < 0) juEH$7N!
return0; C}]143a/Q
else IgEVz^W?h
return previousIndex; 8=-#LVo~c
} " nLWvV1
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} AA5UOg\jI
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抽象业务类 Q*8efzgs|
java代码: HXgf=R/$
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/** >:|jds#
* Created on 2005-7-12 7~H"m/;U&
*/ a0PClbf2.
package com.javaeye.common.business; +HEL ^
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import java.io.Serializable; zcOG[-
import java.util.List; %<\tN^rP
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import org.hibernate.Criteria; ~;@\9oPpz%
import org.hibernate.HibernateException; yAQ)/u[|
import org.hibernate.Session; G$t:#2
import org.hibernate.criterion.DetachedCriteria; R<Ct{f!
import org.hibernate.criterion.Projections;
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import emG1Wyl
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org.springframework.orm.hibernate3.HibernateCallback; O
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import |`O210B@
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org.springframework.orm.hibernate3.support.HibernateDaoS & sgzSX
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upport; 0}-MWbG
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import com.javaeye.common.util.PaginationSupport; qU^`fIa
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public abstract class AbstractManager extends },,K6*P
}@vf=jm>
HibernateDaoSupport { NW~`oc)NS
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privateboolean cacheQueries = false; UQq Qim
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privateString queryCacheRegion; R]NCD*~
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publicvoid setCacheQueries(boolean %Vhj<gN
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cacheQueries){ xpWY4Q
this.cacheQueries = cacheQueries; &G_XgQsg{
} e|4U2\&3y
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publicvoid setQueryCacheRegion(String \N.Bx
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queryCacheRegion){ ?zK\!r{
this.queryCacheRegion = }VqCyJu&{
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queryCacheRegion; ?S'Wd=
} .x_F4 #Ka
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publicvoid save(finalObject entity){ 7*@BCu6
getHibernateTemplate().save(entity); G3gEL)b*
} h!
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publicvoid persist(finalObject entity){ ^"+Vx9H"{
getHibernateTemplate().save(entity); /e7BW0$1
} 6f&qtJQ<A
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publicvoid update(finalObject entity){ ?{r -z3@ N
getHibernateTemplate().update(entity); Q\aC:68
} ),I g u
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publicvoid delete(finalObject entity){ ADB,gap
getHibernateTemplate().delete(entity); v|:TYpku3
} nw=:+?
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publicObject load(finalClass entity, T_oL/x_;
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finalSerializable id){ lGX8kAv?
return getHibernateTemplate().load K*N8Vpz(
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(entity, id); 3PEW0b*]Pf
} "BvDLe':
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publicObject get(finalClass entity, \8]("l}ms8
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finalSerializable id){ ML7qrc;Rx
return getHibernateTemplate().get d8VFa'|
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(entity, id); ~/;shs<9EM
} V(F1i%9l g
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publicList findAll(finalClass entity){ }M &hcw<
return getHibernateTemplate().find("from 1
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" + entity.getName()); $Fv|w9
} 2 P9{?Y
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publicList findByNamedQuery(finalString 8\m[Nuq5
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namedQuery){ =]P|!$!}0
return getHibernateTemplate qKNHhXi
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().findByNamedQuery(namedQuery); ._(5; PB"
} "*N]Y^6/A
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publicList findByNamedQuery(finalString query, %=5 m!"F
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finalObject parameter){ >H,PST
return getHibernateTemplate *[tLwl.
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().findByNamedQuery(query, parameter); *zWf8X
} j4E`O%@^
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publicList findByNamedQuery(finalString query, x_#'6H\1ga
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finalObject[] parameters){ 5/i]Jni
return getHibernateTemplate .>@]Im
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().findByNamedQuery(query, parameters); Env_??xq
} i 8:^1rHp)
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publicList find(finalString query){ &\<?7Qj3U|
return getHibernateTemplate().find jWh}cM=
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(query); wg|/-q-
} WR}<^ax
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publicList find(finalString query, finalObject Q&e*[l2M6
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parameter){ :6W* ;<o
return getHibernateTemplate().find xN44>3#
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(query, parameter); nw
} 9~}.f1z
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public PaginationSupport findPageByCriteria e%KCcU
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(final DetachedCriteria detachedCriteria){ -{eI6#z|\A
return findPageByCriteria ?xtP\~
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 7DIFJJE'
} Mgg m~|9)
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public PaginationSupport findPageByCriteria ]/od p/jm
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(final DetachedCriteria detachedCriteria, finalint h2vD*W
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startIndex){ |\SwZTr
return findPageByCriteria lM[FT=M
1^ y^b{
(detachedCriteria, PaginationSupport.PAGESIZE, )%~<EJ*&Z
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startIndex); yQquGu
} N@\`DO
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public PaginationSupport findPageByCriteria Dh .<&ri
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(final DetachedCriteria detachedCriteria, finalint n!%'%%o2v
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pageSize, p-B
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finalint startIndex){ $'Qv
{
return(PaginationSupport) <>fT_
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getHibernateTemplate().execute(new HibernateCallback(){ ^MUvd
publicObject doInHibernate =X=m_\=~@
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(Session session)throws HibernateException { }Bn`0;]
Criteria criteria = GqD_6cdh
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detachedCriteria.getExecutableCriteria(session); OLyl.#J
int totalCount = 3ULn ]jA
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((Integer) criteria.setProjection(Projections.rowCount VU\{<j{
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()).uniqueResult()).intValue(); g)^g_4
criteria.setProjection M]A!jWtE
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(null); t? [8k&Z
List items = Y]H,rO
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criteria.setFirstResult(startIndex).setMaxResults 0Y9fK? (
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(pageSize).list(); P6u%-#
PaginationSupport ps = rjL4t^rT
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new PaginationSupport(items, totalCount, pageSize, 0v'!(&m
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startIndex); 8U7X/L
return ps; qBqh>Wo
} gR@,"6b3
}, true); ?a'P;&@7
} #]lK! :
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public List findAllByCriteria(final t(=Z@9)]4F
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DetachedCriteria detachedCriteria){ eX <@qa4<
return(List) getHibernateTemplate lH%-#2]
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().execute(new HibernateCallback(){
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publicObject doInHibernate z*G(AcS)
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(Session session)throws HibernateException { R![4|FR
Criteria criteria = >2dF^cDE-3
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detachedCriteria.getExecutableCriteria(session); ,_RPy2N
return criteria.list(); :x36Z4:
} Yo[Pu< zR
}, true); P2sM3C
} 's 'H&sa
: 5<u!-}
public int getCountByCriteria(final Q'Vejz/
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DetachedCriteria detachedCriteria){ AMc`qh
Integer count = (Integer) y~;w`5;|
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getHibernateTemplate().execute(new HibernateCallback(){ %2<u>=6byG
publicObject doInHibernate SX@zDuM
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(Session session)throws HibernateException { ~=Q Tv8
Criteria criteria = }+i~JK
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detachedCriteria.getExecutableCriteria(session); Wtqv
return GKa_6X_
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criteria.setProjection(Projections.rowCount o1)8?h
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()).uniqueResult(); (K3eb
} dIOiP\^
}, true); n0tVAH'>
return count.intValue(); d2(3 ,
} )m.U"giG++
} x$=""?dd
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用户在web层构造查询条件detachedCriteria,和可选的 f'%Pkk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 EN{o3@ O'
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PaginationSupport的实例ps。 M*7:-Tb]C
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ps.getItems()得到已分页好的结果集 Bd>a"3fA
ps.getIndexes()得到分页索引的数组 p5JRG2zt
ps.getTotalCount()得到总结果数 od RtJ[
ps.getStartIndex()当前分页索引 qotWWe#
ps.getNextIndex()下一页索引 B):hm
ps.getPreviousIndex()上一页索引 {`=k$1
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 V3q[ #.o
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 J `
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一下代码重构了。 ~9DD=5\
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我把原本我的做法也提供出来供大家讨论吧: (.N!(;G
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首先,为了实现分页查询,我封装了一个Page类: aYws{Vii
java代码: @t4OpU<'*b
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/*Created on 2005-4-14*/ MyaJhA6c
package org.flyware.util.page; V3c7F4\
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/** DZqY=Sze
* @author Joa vfloha p
* h"t\x}8qq
*/ vk.P| Y-;
publicclass Page { NNw0
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/** imply if the page has previous page */ I@q(P>]X9
privateboolean hasPrePage; @~8*
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/** imply if the page has next page */ XN}^:j_2
privateboolean hasNextPage; P9jPdls
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/** the number of every page */ }0~X)Vgm(
privateint everyPage; 2VaKt4+`
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/** the total page number */ ^/fasl$#
privateint totalPage; Er@OmNT
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/** the number of current page */ M3Oqto<8"
privateint currentPage; *=(vIm[KL
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/** the begin index of the records by the current 'T(@5%Db
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query */ ;bRyk#
privateint beginIndex; >p
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/** The default constructor */ ~Aw.=Yi=
public Page(){ LsO}a;t5
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} QJ2D C
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/** construct the page by everyPage e-*-91D
* @param everyPage do:IkjU~
* */ ?}"39n
public Page(int everyPage){ 'wni.E&
this.everyPage = everyPage; ZY=a[K
} tr|)+~x3
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/** The whole constructor */ 3@\J#mR
public Page(boolean hasPrePage, boolean hasNextPage, #jM-XK
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int everyPage, int totalPage, |H.ARLS
int currentPage, int beginIndex){ pT/z`o$#V
this.hasPrePage = hasPrePage; :f~qt%%/
this.hasNextPage = hasNextPage; DB3qf>@?
this.everyPage = everyPage; (nAL;:$x2
this.totalPage = totalPage; ZdgzPs"
this.currentPage = currentPage; J?C:@Q
this.beginIndex = beginIndex; *USG
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} qKTzigjj
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/** +`tk LvM
* @return @MO/LvD
* Returns the beginIndex. "3/&<0k
*/ hkMVA
publicint getBeginIndex(){ 1Eb2X}XC
return beginIndex; nF$HWp>
} 3~:9ZWQ/
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/** VS >xvF
* @param beginIndex j4I ~
* The beginIndex to set. (eSsx/
*/ |}b~YHTs
publicvoid setBeginIndex(int beginIndex){ &x7iEbRs
this.beginIndex = beginIndex; +lxjuEiae
} aYn5AP'PH
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/** V-eRGSx
* @return _s*p$/V\
* Returns the currentPage. UE/JV_/S;
*/ No`*-> R
publicint getCurrentPage(){ hZlHY9[t?
return currentPage; Ec@cW6g(%
} &gKDw!al
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/** X9ZHYlr+Q
* @param currentPage tQas_K5
* The currentPage to set. KWojMPs
*/ RLZfXXMn
publicvoid setCurrentPage(int currentPage){ |<'6rJ[i>
this.currentPage = currentPage; [>t;P,
} ]|tR8`DGZ%
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/** %z=:P{0UQ
* @return ka6E s~
* Returns the everyPage. %-a;HGbZn
*/ `mA;1S
publicint getEveryPage(){ ]6M,s0
return everyPage; p]ujip
} (;&}\OX6nm
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/** '~
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* @param everyPage 3dlY_z=0
* The everyPage to set. No)0|C8:
*/ at4JLbk
publicvoid setEveryPage(int everyPage){ D, Gv nfY
this.everyPage = everyPage; h3-^RE5\`S
} -+Ot'^
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/** d%. |MAE
* @return E- [Eg
* Returns the hasNextPage. V:>r6
*/ 0N~kq-6.\
publicboolean getHasNextPage(){ YC')vv3o(
return hasNextPage; H6{Bx2J1*
} '&e8;X
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/** k1oJ<$Q
* @param hasNextPage } C:i0Q
* The hasNextPage to set. heL`"Y2'y>
*/ `a83bF35
publicvoid setHasNextPage(boolean hasNextPage){ v?
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this.hasNextPage = hasNextPage; %S%IW
} Hi$R"O
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/** 2x9.>nwhb
* @return W=3#oX.GsU
* Returns the hasPrePage. *hru);OJr
*/ g$^-WmX\m
publicboolean getHasPrePage(){ ~TsRUT
return hasPrePage; /#
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} wN58uV '
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/** }Nd1'BVf
* @param hasPrePage >}\s-/
* The hasPrePage to set. pS|K[:5
*/ ;N?(R\*8
publicvoid setHasPrePage(boolean hasPrePage){ (WJ)!
this.hasPrePage = hasPrePage; DH%PkGn
} ]WY V
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/** FR[I~unqD
* @return Returns the totalPage. NLK1IH#
* PPH;'!>s"
*/ sv?Fx;d
publicint getTotalPage(){ V:'F_/&X?
return totalPage; YLi6GY
} |T@SlNi]
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/** !p).3Kx0
* @param totalPage D\b$$z]q
* The totalPage to set. uxB)dS
*/ RrvC}9ar
publicvoid setTotalPage(int totalPage){ xYCJO(&
this.totalPage = totalPage; %jy$4qAf%
} ~ HhB@G!3
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} \c4jGJ
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 G@#lf@M]
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个PageUtil,负责对Page对象进行构造: Y4HN1
java代码: 6" * <0
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/*Created on 2005-4-14*/ pT->qQ3;
package org.flyware.util.page; U%s@np
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import org.apache.commons.logging.Log; M,_
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import org.apache.commons.logging.LogFactory; gAWi&
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/** zplv.cf#q
* @author Joa }W8A1-UF
* nK :YbLdK,
*/ Sp5:R75vI
publicclass PageUtil { dT*Yv`h
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privatestaticfinal Log logger = LogFactory.getLog Kh\ 7%>K#
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(PageUtil.class); qIQ=OY=6
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/** xyL)'C
* Use the origin page to create a new page 0fXMY-$I
* @param page 'G l~P><e
* @param totalRecords cb /Q<i
* @return isL
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*/ ]5"k%v|
publicstatic Page createPage(Page page, int %US&`BT!
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totalRecords){ )~wKRyQff
return createPage(page.getEveryPage(), U_"!\lI_yg
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page.getCurrentPage(), totalRecords); NSz}
} oL@ -<;zKO
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/** uVn"L:_
* the basic page utils not including exception Ahwi
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handler |ZH(Z}m
* @param everyPage '-%1ILK$3r
* @param currentPage .@,t}:lD
* @param totalRecords d#0:U
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* @return page z9ADF(J?0'
*/ >n09K8
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publicstatic Page createPage(int everyPage, int Jx.fDVJ
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currentPage, int totalRecords){ 3@I0j/1#k1
everyPage = getEveryPage(everyPage); />S^`KSTM
currentPage = getCurrentPage(currentPage); - j3Lgm
int beginIndex = getBeginIndex(everyPage, oN,1ig
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currentPage); rpRyB9
int totalPage = getTotalPage(everyPage, v;<gCzqQh
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totalRecords); hi[nUG(OI
boolean hasNextPage = hasNextPage(currentPage, '|SO7}`;Q
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totalPage); "V>}-G&
boolean hasPrePage = hasPrePage(currentPage); %i9 e<.Ot
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returnnew Page(hasPrePage, hasNextPage, T ?[28|
everyPage, totalPage, 1 jidBzu<
currentPage, skcyLIb
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beginIndex); cuQ!"iH
} &!CVF
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privatestaticint getEveryPage(int everyPage){ T o["o!(;z
return everyPage == 0 ? 10 : everyPage; GJ*IH9YR
} 1<BKTMBq?{
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privatestaticint getCurrentPage(int currentPage){ ,-e}Xw9
return currentPage == 0 ? 1 : currentPage; z,TH}s6
} blgA`)GI
X,v.1#[
privatestaticint getBeginIndex(int everyPage, int +^Xf:r`
G
ZW [&7[4
currentPage){ N5 5F5
return(currentPage - 1) * everyPage; Q ]CMm2L^f
} :8)Jnh\5
#BLHHK/[
privatestaticint getTotalPage(int everyPage, int 1VgGF^cYR
3<^Up1CaZ
totalRecords){ r
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int totalPage = 0; oK\zyNK
H
d|p@$I
if(totalRecords % everyPage == 0) s>J5.Z7"'j
totalPage = totalRecords / everyPage; OvX&5Q5
else ' 4FH9J
totalPage = totalRecords / everyPage + 1 ; `"=>lu2H
Lm4`O%
return totalPage; n2mO-ZXud
} ircF3P>a?
qk<jvha
privatestaticboolean hasPrePage(int currentPage){ zTa5N
return currentPage == 1 ? false : true; 9)oi_U.
} +F)-n2Bi
`>
%QCc\
privatestaticboolean hasNextPage(int currentPage, Jo {:]:
yu'-'{%
int totalPage){ -hXKCb4YU
return currentPage == totalPage || totalPage == #sw4)*v
o.ZR5 `.
0 ? false : true; n2K1X!E$
} gq?7O<
fd
)v{OC
2f[;U"
} WLl8oE<X
M@xU59$@
s0iG|vw
qofAA!3z
9G/!18 X?f
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }MQ:n8
=de'Yy:\-
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 8ao-]QoMZ
XkA] 9,@
做法如下: i.t%a{gL
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 G!6b
)4L-
5sT3|yq
的信息,和一个结果集List: to?! qxn
java代码: 1sHjM%
mXz*Gi
uHKEt[PS$
/*Created on 2005-6-13*/ *a Z1 4
package com.adt.bo; 76 !LMNf
FaeKDbLJr
import java.util.List; 9vV==A#
3&y-xZ u]
import org.flyware.util.page.Page; AXlVH%'
S~3|1Hw*tN
/** Rge>20uTl$
* @author Joa wOf8\s1
*/ UH MJ(.Wa-
publicclass Result { +Vk L?J
8._uwA<[
private Page page; -$:;en?
(F&LN!Hn>p
private List content; EIRDH'[L
b=5w>*
/** 3Z?ornS
* The default constructor 5mZ2CDV
*/ TLsF c^X
public Result(){ NA0nF8ek
super(); |`o|;A]
} bo|THS
LTe ({6l0
/** gF,=rT1:>r
* The constructor using fields }i8y/CA
* #^L&H
oo6
* @param page r]!#v{#.
* @param content k;^$Pd?t
*/ Uoe{,4T
public Result(Page page, List content){ p-iFe\+
this.page = page; _{jC?rzb
this.content = content; Z^> 4qf,k
} D3C 7f'
fQ5v?(
/** ID_4M_G
* @return Returns the content. p3Ux%/ZqPV
*/ vW &G\L
publicList getContent(){ 9E ^!i
return content; @*y4uI6&
} [`@M!G.
7su2A>Ix
/** qTJ0}F
* @return Returns the page. M#gxiN
*/ "%Ok3Rvv
public Page getPage(){ ." xP{
return page; m8L *LB
} r0}x:{$M
A^,E~Z!x
/** jc"sPr v5
* @param content (}39f
* The content to set. 6=/sEz S'
*/ J3mLjYy
public void setContent(List content){ J]U_A/f
this.content = content; <mFDC?j
} m+!.H\
HFFG4'
/** DT`HS/~fH
* @param page ;}SGJ7
* The page to set. Ye3o}G9z
*/ 84WDR?
publicvoid setPage(Page page){ Oz6$u
this.page = page; |N`0G.#
} PRU&y/zZmG
} -W9DH^EL<
Nud =K'P=
1\fx57a\
Sh(ys*y>
}>6e-]MHfR
2. 编写业务逻辑接口,并实现它(UserManager, He=C\"
VFf;|PHS
UserManagerImpl) Q2 !GWz$
java代码: qob!AU|
6-|?ya
ms0V1`
/*Created on 2005-7-15*/ }*(_JR4G
package com.adt.service;
sm`c9[E
7y=O!?*
import net.sf.hibernate.HibernateException; h}a}HabA
mFTuqujO
import org.flyware.util.page.Page; i F+:j8
b
?xqS#^Z
import com.adt.bo.Result; !+eU
!K(
/** Da 7(jA+
* @author Joa $Y7VA
*/ :%h1Q>F
publicinterface UserManager { 9 jjeZc'
w( V%EEk
public Result listUser(Page page)throws $_F_%m"\
j;`pAN('
HibernateException; rci,&>L"
oT\K P
} Ga5s9wC
cjL)M=pIS
a_c(7bQ
B2kZ_4rB
fx|d"VF[
java代码: t}k:wzZ@
mI7lv;oN<5
6]iU-k0b
/*Created on 2005-7-15*/ W+a/>U
package com.adt.service.impl; #HgNwM
#A5X,-4G
import java.util.List; UE^o}Eyg
=Q<VU/
import net.sf.hibernate.HibernateException; aM
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Z
01A~_
import org.flyware.util.page.Page; O4X03fUx
import org.flyware.util.page.PageUtil; ]B )nN':
c?CD;Pk
import com.adt.bo.Result; rx9*/Q0F
import com.adt.dao.UserDAO; jVnTpa!A
import com.adt.exception.ObjectNotFoundException; 8vuTF*{yZ
import com.adt.service.UserManager; o6A$)m5V
hM]Z T5;<
/** MU$tX
* @author Joa
`vH|P
*/ Kn->R9Tl
publicclass UserManagerImpl implements UserManager { Bg),Q8\I
^mq(j_E.
private UserDAO userDAO; -7&ywgxl
{?:]'c
/** ;\w3IAa|V
* @param userDAO The userDAO to set. b+a+OI D
*/ bRu9*4t
publicvoid setUserDAO(UserDAO userDAO){ ht%qjE
this.userDAO = userDAO; Az@@+?,%Y
} X[$h &]
he~8V.$
/* (non-Javadoc) $\ZWQct
* @see com.adt.service.UserManager#listUser fJ8>nOh
Q`*U U82!
(org.flyware.util.page.Page) <5G(Y#s/?
*/ B(M-;F
public Result listUser(Page page)throws `F/R:!v
E "=4(
HibernateException, ObjectNotFoundException { +#,J`fV%
int totalRecords = userDAO.getUserCount(); Z5TA4Q+Q
if(totalRecords == 0) Rf0so
throw new ObjectNotFoundException we_CF*zj
]AA|BeL?|
("userNotExist"); d2eXN3"
page = PageUtil.createPage(page, totalRecords); :jv(-RTI
List users = userDAO.getUserByPage(page); L'Cd`.yVO
returnnew Result(page, users); A4,%l\di<
} BlpyE[h
T
JE}VRMNr
} 5,,'hAq_
!@lx|=#
a!bW^?PcK
U Y*`R
bXJ(QXHd%
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 d_we?DZ|
a_!H_J
询,接下来编写UserDAO的代码: N
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b3cV
3. UserDAO 和 UserDAOImpl:
y ]t19G+
java代码: JRC2+BU
/
w=fWW^>bP
2z{B
/*Created on 2005-7-15*/ N4;g"k b
package com.adt.dao; ,j XK
s``a{ HZ
import java.util.List; JYWoQ[ZO#>
Q
import org.flyware.util.page.Page; c<Cf|W
p^ (Z
import net.sf.hibernate.HibernateException; w#)u+^ -
T(u;<}e@[
/** +JYb)rn$^
* @author Joa &ic'!h"
*/ 3ux7^au
publicinterface UserDAO extends BaseDAO { ^Lb\k|U,\
itNuY<"
publicList getUserByName(String name)throws Fk49~z
cEa8l~GC<
HibernateException; Fy\q>(v.
Jvc<j:{^w
publicint getUserCount()throws HibernateException; vWmp?m
tW~kn9glZ
publicList getUserByPage(Page page)throws +pgHCzwJE
^[SW07o~
HibernateException; I)yaR+l
}O+xs3Uv
} iPl,KjGk
<xSh13<
&-FG}|*4M
mlc8q s
7~J>Ga
java代码:
kntY2FM
"7EK{6&jQ
^ U,iDK_
/*Created on 2005-7-15*/ 7*{l\^ism;
package com.adt.dao.impl; o5J6Xi0+
i. )^}id
import java.util.List; ].d%R a:{
m7NWgXJ
import org.flyware.util.page.Page; c`x4."m
d#+Nef5
import net.sf.hibernate.HibernateException; H.|I|XRG/
import net.sf.hibernate.Query; BegO\0%+
MR,I`9P e
import com.adt.dao.UserDAO; F&uiI;+zJ
8y5"X"U
/** #y: F3$c
* @author Joa Zgh~7Z/
*/ " 4#&tNQ
public class UserDAOImpl extends BaseDAOHibernateImpl .n+
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w=?nD6Xhz
implements UserDAO { k waZn~
Y$XzZ>VW
/* (non-Javadoc) 68GH$ji
* @see com.adt.dao.UserDAO#getUserByName B.4e4%BBS
JtY$AP$
(java.lang.String) ~q+AAWL
*/ Q?T+^J
publicList getUserByName(String name)throws G*EF_N.G0
M/Z$?nd_H
HibernateException { TU)Pi.Aa
String querySentence = "FROM user in class @su<_m6'
b]?5r)GK
com.adt.po.User WHERE user.name=:name"; C3^3<
Query query = getSession().createQuery } *)l
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(querySentence); SVwxK/Fci
query.setParameter("name", name); zQ:nL*X'Z"
return query.list(); &a'mG=(K_c
} !BW!!/U
b=BNbmX
/* (non-Javadoc) 8J&9}@y
* @see com.adt.dao.UserDAO#getUserCount() z[ ;n2o|s
*/ nLAwo3
publicint getUserCount()throws HibernateException { du}HTrsC
int count = 0; hd9~Zw]V
String querySentence = "SELECT count(*) FROM 72RTEGy
nm`(;<W
user in class com.adt.po.User"; `+(n+QS _
Query query = getSession().createQuery bxPa|s?
{q$U\y%Rq
(querySentence); w5y.kc;
count = ((Integer)query.iterate().next e8):'Cb
y|BHSc3
()).intValue(); uPcx6X3]
return count; p q?# X0
} yqK_|7I+
|FT.x9e-
/* (non-Javadoc) m;"[b (u
* @see com.adt.dao.UserDAO#getUserByPage `K0.6i [p
~X2# z|
(org.flyware.util.page.Page) ~)$R'=
*/ k>MXOUaW.
publicList getUserByPage(Page page)throws jqvw<+#
~}p k^FA
HibernateException { E`HA0/
String querySentence = "FROM user in class c"knzB vy
`Ivt)T+n;
com.adt.po.User"; n(z$u)Y
Query query = getSession().createQuery XFs7kTY
:Kyr}-
(querySentence); 9wc\~5{li
query.setFirstResult(page.getBeginIndex()) K)l*$h&-
.setMaxResults(page.getEveryPage()); D`Vb3aNB=L
return query.list(); #p;<X|Hc}8
} 2=fLb7
GCQOjqiR
} cEp/qzAiD%
S.iUiS"
`ba<eT':
>op/<?<
NR&a
er
至此,一个完整的分页程序完成。前台的只需要调用
He4q-\ht
S9[Up}`
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?5Z-w
t3}_mJ
的综合体,而传入的参数page对象则可以由前台传入,如果用 #,lbM%a
\QSD*
webwork,甚至可以直接在配置文件中指定。 ~ cu+QR)
( Ygy%O%
下面给出一个webwork调用示例: *3RD\.jPX
java代码: liB~vdqj
^cW{%R>XY
=$~x]
/*Created on 2005-6-17*/ xzMpT ZQ
package com.adt.action.user; 2.j0pg .
;CL^2{
import java.util.List; 8zeD%Uv
V#1v5mWVx
import org.apache.commons.logging.Log; LM"b%
import org.apache.commons.logging.LogFactory; j _E(h.
import org.flyware.util.page.Page; N/0Q`cQ-
KVoi>?a
import com.adt.bo.Result; )i39'0a
import com.adt.service.UserService; R. ryy
import com.opensymphony.xwork.Action; P:'y}a-
<;b
/** 7~MWp4.
* @author Joa }EfRYE$E
*/ ou|3%&*"
publicclass ListUser implementsAction{ b[n6L5P5m2
@ohJ'
privatestaticfinal Log logger = LogFactory.getLog RC"xnnIJv
b1e)w?n
(ListUser.class); 86&r;c:
`i!-@WN"
private UserService userService; Q3)[
*61e
E9 #o0Di
private Page page; 1U~'8=-
;rCCkA6
privateList users; V^9%+L+E5
~te{9/
/* /oM&29 jy
* (non-Javadoc) ~fgS"F^7n
* K}S=f\Q]
* @see com.opensymphony.xwork.Action#execute() ?
zic1i
*/ y(K:,CI
publicString execute()throwsException{ b$Bq#vdg:
Result result = userService.listUser(page); ok&v+A
page = result.getPage(); .$x822
users = result.getContent(); <&M5#:u
return SUCCESS; aJNsJIY+
} xdsF! Zb
%%O_:@9x,
/** 7,9zj1<
* @return Returns the page. \w{fq+G
*/ $/JnYkL{m
public Page getPage(){ U@:iN..
return page; BS3BJwf;
f
} T:j!a{_|
ORV'dr
/** 7XIG ne%v
* @return Returns the users. }W]k1Bsx
*/ yF&?gPh&
publicList getUsers(){ K)8 m?sf/
return users; v[y|E;B
} E"H> [E
0jefV*3qpB
/** '-X913eG!
* @param page j7&0ckN&G
* The page to set. "l09Ae'V
*/ w+ibY
publicvoid setPage(Page page){ YC~kq?
this.page = page; p7)b@,
} :}w^-I"
L@5g#mSl
/** Zo(QU5m0
* @param users 7\;gd4Ua1
* The users to set. fm%-wUgj
*/ Op<|Oz$Q|l
publicvoid setUsers(List users){ myY@Wp
this.users = users; ]
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} ;6zp,t0
?#;zB
/** @)wNINvD
* @param userService i_;]UvP
* The userService to set. *8QGv6*vQ
*/ 8[z& g%u
publicvoid setUserService(UserService userService){ QVrMrm+vRv
this.userService = userService; MU&P+Wr
} F_Mi/pB^`9
} G@n%P~
3UX} )mW
=G2A Ufn
QI2T G,
A|U_$!cLZ
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, D3%`vqu&
vo DTU]pf
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 'roZ:NE
x-{awP
么只需要: *[_>d.i
java代码: AU
+2'
s8N\cOd#i
#(NkbJ5ka
<?xml version="1.0"?> BK:S:
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork _-I 0f##.
3F0:v,+;
1.0//EN" "http://www.opensymphony.com/xwork/xwork- y/@.T\p
W|kKH5E&
1.0.dtd"> rj].bGQ,+
# nh;KlI0
<xwork> K:eP Il{JE
8.Ty
,7Z
<package name="user" extends="webwork- 6,|)%~VUm
ojitBo~
interceptors"> xem:#>&r
\YBY"J
<!-- The default interceptor stack name V+l>wMeo
uU]4)Hp
--> ;-d :!*
<default-interceptor-ref o5FBqt
obE_`u l#
name="myDefaultWebStack"/> 93d ht
B6b {hsO
<action name="listUser" [sY>ac
`QlChxd
class="com.adt.action.user.ListUser"> 0 .dSP$e
<param r`L$[C5I
<vV?VV([
name="page.everyPage">10</param> Ot]PH[+
<result
:RW0<
HJ*W3Mg
name="success">/user/user_list.jsp</result> a[GlqaQy+-
</action> b='YCa
"+ji`{
</package> #9Z*.
5xHl6T+
</xwork> r=+r5k"`
H{P"$zj`l
M+ gYKPP
'qhA4W9
}cE,&n
}_L@CpG
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 v:<UbuJw
KPUc+`cN%
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。 &k?Mt#J
<c{RY.1[
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 -_ [Z5%B
#$Z|)i]w
94F9f^ L
j%KLp4J/e
SA|f1R2uS
我写的一个用于分页的类,用了泛型了,hoho -<i&`*zG
fV_(P_C
java代码: , c/\'k\K)
Nze#u;
m4*Rr
package com.intokr.util; cV5Lp4wY?
?zN v7Bj
import java.util.List; (+ 9_nAgZ,
HQ+:0"B
/** xS,#TU;)Ol
* 用于分页的类<br> GjA;o3(
* 可以用于传递查询的结果也可以用于传送查询的参数<br> @M"h_Z1#
* pVw)"\S%
* @version 0.01 d3(T=9;f2
* @author cheng -iS\3P.
*/ u[^(s_
public class Paginator<E> { Y2w 9]:J
privateint count = 0; // 总记录数 M*E4:A9_M
privateint p = 1; // 页编号 r$6z{Na\[
privateint num = 20; // 每页的记录数
#oi4!%*M
privateList<E> results = null; // 结果 fdCsn:
.c+RFX@0
/** LeY\{w
* 结果总数 HT5G HkT
*/ ])a?ri
publicint getCount(){ ]RQQg,|D
return count; A[ ZJS
} _#e='~;
bI=\n)sEz
publicvoid setCount(int count){ z1F[okLA
this.count = count; S~}?6/G.
} &S<tX]v
<Dt,FWWkv'
/** s0.yPA
* 本结果所在的页码,从1开始 Ni{(=&*=
* PS@`
=Z
* @return Returns the pageNo. |]]Xee]
*/ Zi2NgVF
publicint getP(){ C 9,p-
return p; vu YH+
} u/cL[_Q
h&5H`CR[
/** %n9}P ,
?
* if(p<=0) p=1 *#frbV?;
* `qSNS->
* @param p U^~K-!0
*/ H4 &
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publicvoid setP(int p){ >&aFSL,f
if(p <= 0) IX^k<Jqr
p = 1; f
7et
this.p = p; 7^Jszd:c08
} ^Y~ ,s
=6q?XOM
/** o'%F*>#v
* 每页记录数量 C&3#'/&
*/ #*
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publicint getNum(){ )AqM?FE4R
return num; OtF{=7
} r&xqsZ%R
Z.:5<oEKg
/** Yk:fV &]
* if(num<1) num=1 5}~*,_J2Z
*/ oFHVA!lqe
publicvoid setNum(int num){ 9ToM5oQ
if(num < 1) J~DP*}~XK
num = 1; 7~eo^/PbS
this.num = num; -^$CGRE6A
} bP Er+?fu
]<4Yor}t{;
/** /[GOs*{zB
* 获得总页数 f3V&i)w(
*/ sxO_K^eD
publicint getPageNum(){ r NqJL_!
return(count - 1) / num + 1; WMZa6cH
} HQaKG4Z
[lQp4xgxi
/** ~5`rv1$
* 获得本页的开始编号,为 (p-1)*num+1 g 6>RyjN
*/ }`IN5NdYp
publicint getStart(){ c$?qN&X_K
return(p - 1) * num + 1; eP'e_E
} nPfVZGt
<hdR:k@#
/** //e.p6"8h
* @return Returns the results. _w^p~To^
*/ C\.? 3
publicList<E> getResults(){ ?;|$R
return results; s:R>uGYOd
} :I F&W=?9
1
xiq]~H
public void setResults(List<E> results){ I\Y/*u
this.results = results; sG0cN;I]t
} 9
o-T#~i
1F/`*z
public String toString(){ gUL`)t\} *
StringBuilder buff = new StringBuilder ePIBg(
lV`y6 {o#T
(); !o:RIwS3
buff.append("{"); vp4!p~C{
buff.append("count:").append(count); 5D-xm$8C
buff.append(",p:").append(p); K,|Gtaa~
buff.append(",nump:").append(num); s3_i5,y
buff.append(",results:").append Z=R>7~H
(~}yt .7K
(results); 20zIO.&o
buff.append("}"); B HoZ}1_
return buff.toString(); %9-).k
} =NF},j"
05DK-Wh?
} >Bskw2
'8i
np[_
\0(QO8.