Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d6"B_,*b
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Nv\<>gA:
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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 +Z%8X!Q
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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 )auuk<
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分页支持类: `O}bPwa{>
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java代码: R]_fe4Y0
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package com.javaeye.common.util; QEl~uhc3
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import java.util.List; :,=Z)e
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publicclass PaginationSupport { /M~rmIks
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publicfinalstaticint PAGESIZE = 30; IR*:i{
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privateint pageSize = PAGESIZE; +4Lj}8,
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privateList items; kA&ul
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privateint totalCount; 1z=}`,?>
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privateint[] indexes = newint[0]; & A @!g
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privateint startIndex = 0; =_H)5I_\
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public PaginationSupport(List items, int ak;S Ie
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totalCount){ |)u|@\{
setPageSize(PAGESIZE); ]ch=D
setTotalCount(totalCount); W[j7Vi8v
setItems(items); 0B~Q.tyP
setStartIndex(0); @7<m.?A!
} >eaK@u-'0
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public PaginationSupport(List items, int v4wXa:CJ
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totalCount, int startIndex){ 1oIu~f{`
setPageSize(PAGESIZE); wenJ (0L|
setTotalCount(totalCount); %uhhQ<zs%
setItems(items); RlTVx:
setStartIndex(startIndex); We*c_;@<
} Q Ph6
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public PaginationSupport(List items, int &b&o];a
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totalCount, int pageSize, int startIndex){ L\asrdL?=
setPageSize(pageSize); "n=Ih_J
setTotalCount(totalCount); q CB9z
setItems(items); mPo] .z
setStartIndex(startIndex); _a=f.I
}
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publicList getItems(){ ZI#Xh5
return items; $U/_8^6B0
} !#8=tO
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publicvoid setItems(List items){ K1>(Fs$
this.items = items; Vl+,OBy
} cZXra(AD
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publicint getPageSize(){ H=k*;'
return pageSize; bwAL:
} /q8?xP.
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publicvoid setPageSize(int pageSize){ }~28UXb23
this.pageSize = pageSize; >xE{&
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} /1q] D8
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publicint getTotalCount(){ Z;JZ<vEt92
return totalCount; ; i><03
} emI]'{_G
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publicvoid setTotalCount(int totalCount){ 4';tMiz
if(totalCount > 0){ >, }m=X8
this.totalCount = totalCount; K06/ D!RD4
int count = totalCount / yw;!KUKb|
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pageSize; 6Pa
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if(totalCount % pageSize > 0) d.&~n`Rv!p
count++; %lU$;cY
indexes = newint[count]; OAQ'/{~7
for(int i = 0; i < count; i++){ ,FPgbs
indexes = pageSize * +>5
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} cNG6 A4
}else{ X7]vXo*
this.totalCount = 0; <!vAqqljt
} Uq6..<#
} n[/|M
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publicint[] getIndexes(){ s"|N-A=cS
return indexes; +6{KrREX)
} ngJES`0d
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publicvoid setIndexes(int[] indexes){ G#! j`
this.indexes = indexes; (Rk g
} w`Dzk.2
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publicint getStartIndex(){ &~Q ?k
return startIndex; JPk3T.qp
} C6eo n4Ut
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publicvoid setStartIndex(int startIndex){ [J+K4o8L<A
if(totalCount <= 0) "t"=9:_t
this.startIndex = 0; L$x/T3@
elseif(startIndex >= totalCount) <u"#Jw/VP
this.startIndex = indexes yREO;m|o
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[indexes.length - 1]; XI,F^K
elseif(startIndex < 0) xTM&SVNbL_
this.startIndex = 0; [zR
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else{ JCZJ\f*EZ
this.startIndex = indexes f(?`PD[
+Z[%+x92
[startIndex / pageSize]; qhpq\[U6in
} ?xX`_l
} ^dYLB.'=
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publicint getNextIndex(){ fK^FD&sF
int nextIndex = getStartIndex() + ki^[~JS>'
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pageSize; i\rI j0+
if(nextIndex >= totalCount) @Cm"lv.hz
return getStartIndex(); 9#6ilF:F
else vVLR9"rHM
return nextIndex; tO?*x/XC{
} cVn7jxf
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publicint getPreviousIndex(){ BoIe<{X(9
int previousIndex = getStartIndex() - Dl/UZ@8pl
c e=6EYl
pageSize; miHW1h[=
if(previousIndex < 0) zAB-kE\)
return0; [;5HI'px
else qg6Hk:^r
return previousIndex; ,l7ty#j
} 6aQ{EO-]'=
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} =$Q3!bJ
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抽象业务类 B?Y%y@.
java代码: o(~JZik
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/** ieS5*@^k
* Created on 2005-7-12 q}BQu@'H
*/ ~w[zX4@
package com.javaeye.common.business; ^Z:x poz,
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import java.io.Serializable; A7_*zR@
import java.util.List; ,%nmCetD@
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import org.hibernate.Criteria; "TjR]jnV(
import org.hibernate.HibernateException; /'VCJjzZ
import org.hibernate.Session; ocgbBE
import org.hibernate.criterion.DetachedCriteria; ~T4=Id
import org.hibernate.criterion.Projections; Z/x<U.B
import *bRH,u
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org.springframework.orm.hibernate3.HibernateCallback; <JH0 &
import #2HygS
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org.springframework.orm.hibernate3.support.HibernateDaoS 4?yc/F=kI
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upport; \HK#d1>ox
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import com.javaeye.common.util.PaginationSupport; ^ACp_RM
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public abstract class AbstractManager extends (vj2XiO^+
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HibernateDaoSupport { rX{|]M":T
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privateboolean cacheQueries = false; ^*{xTB57
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privateString queryCacheRegion; Ha+FH8rZ
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publicvoid setCacheQueries(boolean &aF_y_f\
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cacheQueries){ <
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this.cacheQueries = cacheQueries; 1;:2 =8
} -ZyFUGd%
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publicvoid setQueryCacheRegion(String <RhKlCP
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queryCacheRegion){ ]7u8m[@
this.queryCacheRegion = .ySesN: C~
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queryCacheRegion; 3.dUMJ$_
} jZ{S{"j
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publicvoid save(finalObject entity){ ,<vrDHR
getHibernateTemplate().save(entity); "]N QTUb;
}
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publicvoid persist(finalObject entity){ O5=ggG
getHibernateTemplate().save(entity); Y\%}VD2k
} k Lv_P[I
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publicvoid update(finalObject entity){ "rKIXy
getHibernateTemplate().update(entity); !<YRocQY
} quKD\hL$
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publicvoid delete(finalObject entity){ AV2q*
getHibernateTemplate().delete(entity); _ma4
} Y?5yzD:
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publicObject load(finalClass entity, e:,.-Kvzp`
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finalSerializable id){ q;>BltU
return getHibernateTemplate().load eh`V#%S=
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(entity, id); "pWdz}!
} ,jt098W
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publicObject get(finalClass entity, [y{ag{
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finalSerializable id){ O?2<rbx
return getHibernateTemplate().get n7MS{`
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(entity, id); MV/~Rmd.
} -DuiK:mp
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publicList findAll(finalClass entity){ ZK
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return getHibernateTemplate().find("from nEp'l.T
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" + entity.getName()); f C^l9CRY
} Fd\XDc[g
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publicList findByNamedQuery(finalString o6y,M!p@
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namedQuery){ dH/t|.%
return getHibernateTemplate :U:7iP:
1`}fbX;"m)
().findByNamedQuery(namedQuery); )4`Ml*7x
} QhG-1P3#
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publicList findByNamedQuery(finalString query, bMUIe\/v[
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finalObject parameter){ $HXB !$d
return getHibernateTemplate 0%qUTGj
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().findByNamedQuery(query, parameter); op|mRJBq;
} 3N
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publicList findByNamedQuery(finalString query, @\DD|o67
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finalObject[] parameters){ qbEj\
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return getHibernateTemplate 9V66~Bf5
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().findByNamedQuery(query, parameters); `Of wl%G
} >#:/
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publicList find(finalString query){ Uo @NK
return getHibernateTemplate().find psZeu*/r
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(query); jccW8g~
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} +_gT|vlU
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publicList find(finalString query, finalObject )T64(_TE
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parameter){ 0lRH
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return getHibernateTemplate().find Z8&C-yCC
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(query, parameter); ZW?7g+P
} 0v@/I<
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public PaginationSupport findPageByCriteria jOb[h=B"
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(final DetachedCriteria detachedCriteria){ ]hj1.V+
return findPageByCriteria @:7gHRJ!
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ?fmt@@]T?
} aVP|:OAj
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public PaginationSupport findPageByCriteria y@M}T{,/
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(final DetachedCriteria detachedCriteria, finalint <c ovApx
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startIndex){ 30_un
return findPageByCriteria u3wC}Zo
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(detachedCriteria, PaginationSupport.PAGESIZE, {}pqxouE
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startIndex); }iSakq'
} |"yf@^kdC
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public PaginationSupport findPageByCriteria V./w06;0
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(final DetachedCriteria detachedCriteria, finalint w"v'dU^
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pageSize, ]VWfdG
finalint startIndex){ }Hz-h4Z
return(PaginationSupport) Q$)|/Y))
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getHibernateTemplate().execute(new HibernateCallback(){ @E}X-r.^f
publicObject doInHibernate VK'T[5e
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(Session session)throws HibernateException { *yaX:,'\$
Criteria criteria = .gN$N=7<
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detachedCriteria.getExecutableCriteria(session); (b%y$D
int totalCount = zw:C*sY
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((Integer) criteria.setProjection(Projections.rowCount L)lQ&z?
}[z<iij4
()).uniqueResult()).intValue(); v1r_Z($
criteria.setProjection )_v\{N
)@qup _M@
(null); (a}
List items = P=^#%7J/l
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criteria.setFirstResult(startIndex).setMaxResults <{/;1Dru
@%<?GNS O
(pageSize).list(); yvz?4m"_yB
PaginationSupport ps = X
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new PaginationSupport(items, totalCount, pageSize, 4C1FPrh
k=7Gr;;l=p
startIndex); 0i\',h}9
return ps; 8*yo7q&
} WE[m@K[CR
}, true); wm=RD98
} =x^l[>sz
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public List findAllByCriteria(final =#(0)p$EC
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DetachedCriteria detachedCriteria){ ole|J
return(List) getHibernateTemplate
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().execute(new HibernateCallback(){ \V^*44+
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publicObject doInHibernate jJVT_8J
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(Session session)throws HibernateException { 7':f_]
Criteria criteria = h}|6VJ@.
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detachedCriteria.getExecutableCriteria(session); U,<]J*b(@4
return criteria.list(); C]'g:93L
} f<89$/w
}, true); ^Cg^`n?@b
} e3eVvl5]
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public int getCountByCriteria(final =3|pHc hJ4
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DetachedCriteria detachedCriteria){ &xiOTkqB
Integer count = (Integer) tqf&N0*
0||"r&:X
getHibernateTemplate().execute(new HibernateCallback(){ K 3Yw8t2J
publicObject doInHibernate yW\XNX
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(Session session)throws HibernateException { A XBkJ'jd
Criteria criteria = hOPe^e"
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detachedCriteria.getExecutableCriteria(session); gF[6c`-s
return dTN$y\
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criteria.setProjection(Projections.rowCount u#+RUtM
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()).uniqueResult(); >5;N64]!)
} Y{Da+
}, true); e&QS#k
return count.intValue(); /vjGjb=3U
} s=d+GMa
} yGiP[d|tRc
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用户在web层构造查询条件detachedCriteria,和可选的 QjA&IZEC
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 S_!hsY
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PaginationSupport的实例ps。 ImIqD&a-h
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ps.getItems()得到已分页好的结果集 yl-fbYH
ps.getIndexes()得到分页索引的数组
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ps.getTotalCount()得到总结果数 6b?`:$Cw3)
ps.getStartIndex()当前分页索引 <EMkD1e
ps.getNextIndex()下一页索引 =m}TU)4.
ps.getPreviousIndex()上一页索引 ^m*3&x8
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ?g2zmI!U
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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 SIq1X'7
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一下代码重构了。 0G5'Y;8
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我把原本我的做法也提供出来供大家讨论吧: |;P^clS3
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首先,为了实现分页查询,我封装了一个Page类: +?;j&p
java代码: {h#6z>p"u2
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/*Created on 2005-4-14*/ 9e~WK720=
package org.flyware.util.page; Z_FNIM0f
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/** HsnG4OE
* @author Joa \c{R <Hh
*
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*/ W;q+, Io
publicclass Page { Q',m{;;
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/** imply if the page has previous page */ )1f+ld%R
privateboolean hasPrePage; o/cr{>"N
nq'M?c#E
/** imply if the page has next page */ R:A'&;S
privateboolean hasNextPage; vM`7s[oAK
JSgpb?(
/** the number of every page */ WSLy}@`Vx
privateint everyPage; ,/&Z3e
ExCM<$,
/** the total page number */ gg[9u-
privateint totalPage; DLi?'K3t
XJSa]P^B1
/** the number of current page */ R}r~p?(M
privateint currentPage; /b#q*x-b
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/** the begin index of the records by the current e .l!3xY2'
L/?]^!.
query */ 3OP.12^
privateint beginIndex; p0M=t-
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/** The default constructor */ tz4
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public Page(){ ,
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} 5 y
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/** construct the page by everyPage Ma6W@S
* @param everyPage ]p]UTCo!'
* */ Hx
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public Page(int everyPage){ ?TpUf
this.everyPage = everyPage; / p)F>WR
} Zu21L3
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/** The whole constructor */ m'x;,xfY&F
public Page(boolean hasPrePage, boolean hasNextPage, >w.'KR0L
sDC*J\X
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int everyPage, int totalPage, =eBmBn
int currentPage, int beginIndex){ x<ax9{
this.hasPrePage = hasPrePage; {%b
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this.hasNextPage = hasNextPage; *C6 D3y
this.everyPage = everyPage; ~W03{9(Vp8
this.totalPage = totalPage; oNM?y:O
this.currentPage = currentPage; Zx{96G+1
this.beginIndex = beginIndex; bik*ZC?E
} >(3\kiYS
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/** ``|AgIg
* @return OeElMRU"
* Returns the beginIndex. !aNh!
*/ ONX8}Ob~
publicint getBeginIndex(){ +e P.s_t
return beginIndex; ZFvyL8o
} mR+Jws'
*1A&'T2
/** ,9of(T(~
* @param beginIndex :243 H
* The beginIndex to set. >w|*ei:@S
*/ P)6lu8zQ
publicvoid setBeginIndex(int beginIndex){ t6lE#<xZV;
this.beginIndex = beginIndex; Rc[ 0aj:
} 'bu )M1OLi
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/** (\,BxvhG=
* @return 3[IJhR[
* Returns the currentPage. #0"~G][#
*/ +(?>-3_z
publicint getCurrentPage(){ U \oy8FZ
return currentPage; kV&9`c+
} aeP[+ I9
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/** S%mfs!E>
* @param currentPage Ug%_@t/?
* The currentPage to set. 5[gh|I;D
*/ >v+jh(^
publicvoid setCurrentPage(int currentPage){ U|@V
74
this.currentPage = currentPage; h7yqk4'Lq
} Ev9> @~^
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/** Yu3zM79'k
* @return ~i~%~doa
* Returns the everyPage. @jy41eIo
*/ .Zmp ,
publicint getEveryPage(){ w?y6nTg<
return everyPage; xJwG=$o
} T:iP="?{
_.V?A*
/** Sq2P-y!w
* @param everyPage 9X}I>
* The everyPage to set.
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*/ Y&.UIosWb
publicvoid setEveryPage(int everyPage){ {b)~V3rsY
this.everyPage = everyPage; )2e#HBnH
} qu|i;WZE
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/** 'UU\4M
* @return e}yX_Z'P<
* Returns the hasNextPage. Vw{*P2v)
*/ g);^NAA
publicboolean getHasNextPage(){ hJ;$A*Y
return hasNextPage; B 0ee?VC
} Wp0
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/** tt_o$D~kg
* @param hasNextPage ;#/@+4@a&
* The hasNextPage to set. C.Uju`3
*/ kOL'|GgK
publicvoid setHasNextPage(boolean hasNextPage){ ) c2_b
this.hasNextPage = hasNextPage; /=?x{(B>
} BU Z
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/** L1{GL #qV
* @return 5z}w}zdg
* Returns the hasPrePage. 23F/\2MSG
*/ u.XQ&
publicboolean getHasPrePage(){ `:NaEF?Sj
return hasPrePage; d3Mva,bw<
} G3i !PwW
=+:{P?*}
/** =='Td[
* @param hasPrePage J:*-gwv9*m
* The hasPrePage to set. y046:@v(
*/ "SxLN
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publicvoid setHasPrePage(boolean hasPrePage){ K>Fqf
+_
this.hasPrePage = hasPrePage; bUwn}_7b
} hZXXBp
=wWpP-J&
/** {Ro2ouQ!V
* @return Returns the totalPage. 1T&Rc4$Sn7
* jKIxdY:U
*/ {Azn&|%.t
publicint getTotalPage(){ 9pn>-1NJ
return totalPage; BaI $S>/Q
} Ws U)Y&
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/** :ue:QSt(u
* @param totalPage * |.0Myjo
* The totalPage to set. `4?~nbz
*/ HSUI${<
publicvoid setTotalPage(int totalPage){ 0oZsb\
this.totalPage = totalPage; Jzji&A~
} t_z>Cl^u
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F;`; 1
} <*ZJaBwWU~
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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 )>
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个PageUtil,负责对Page对象进行构造: B(a-k?
java代码: v4,h&JLt
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/*Created on 2005-4-14*/ -&x2&WE'
package org.flyware.util.page; 1/1Xk,E
'VyM{:8
import org.apache.commons.logging.Log; Xaz o9J
import org.apache.commons.logging.LogFactory; ok^d@zI
=uk0@hy9b
/** NL=|z=q
* @author Joa v,-{Z1N%m
* G'2#9<c*
*/ _/8FRkx
publicclass PageUtil { :bV mgLgG
EF7+ *Q9
privatestaticfinal Log logger = LogFactory.getLog S1Z2_V
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(PageUtil.class); o./.Q9e7
+y7;81ND
/** 6*4's5>?D
* Use the origin page to create a new page qf@q]wtar
* @param page S:4crI
* @param totalRecords WG*t::NN
* @return Q$& sTM
*/ fH`P[^N
publicstatic Page createPage(Page page, int =ph&sn$;L
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totalRecords){ 6R-&-4
return createPage(page.getEveryPage(), ](tx<3h
t*z~5_/
page.getCurrentPage(), totalRecords); m }a|FS
} H9h@ sSg
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/** !TZhQiorC
* the basic page utils not including exception s+Fi @lg,
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handler UNijFGi
* @param everyPage [Vd[-
* @param currentPage S)QAXjH
* @param totalRecords ur
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* @return page ?88[|;b3
*/ s2?T5oWU
publicstatic Page createPage(int everyPage, int /V3=KY`_J
Q9I
j\HbA"
currentPage, int totalRecords){ WLF0US'
everyPage = getEveryPage(everyPage); 8^Hn"v
currentPage = getCurrentPage(currentPage); .Ha'p.
int beginIndex = getBeginIndex(everyPage, A+y
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currentPage); WZOY)>K
int totalPage = getTotalPage(everyPage, o,U9}_|A
JnHo 9K2.
totalRecords); X;<BzA!H
boolean hasNextPage = hasNextPage(currentPage, ,Y3W?
+!QJTn"3
totalPage); ?)bS['^1)
boolean hasPrePage = hasPrePage(currentPage); <;E
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returnnew Page(hasPrePage, hasNextPage, [SJ6@q
everyPage, totalPage, R@Gq)P9?
currentPage, 0ye!R
4}`
beginIndex); pF
^#}L
} #cj6{%c4
fc/ &X
privatestaticint getEveryPage(int everyPage){ $P1O>x>LIL
return everyPage == 0 ? 10 : everyPage; N`)$[&NG]
} b-3*Nl _%
TKk-;Y=N
privatestaticint getCurrentPage(int currentPage){ qwIa?!8o
return currentPage == 0 ? 1 : currentPage; 4iW'kuK
} D:Q
21Ch
IbcZ@'RSw
privatestaticint getBeginIndex(int everyPage, int >^Se'SE]
Hm+ODv9
currentPage){ D")_;NLE1
return(currentPage - 1) * everyPage; Lh.`C7]
} hp{OL< 2M
^Rx9w!pAN
privatestaticint getTotalPage(int everyPage, int Vi4~`;|&b+
SP|<Tny
totalRecords){ hFiIW77s2
int totalPage = 0; piU/&
c/_+o;Bc
if(totalRecords % everyPage == 0) M$0u1~K
totalPage = totalRecords / everyPage; -s 6![eV
else aR\\<due
totalPage = totalRecords / everyPage + 1 ; <hwy*uBrD
p7:{^
return totalPage; AfG/JWSo}
} qc#)!
=]-j;#'&
privatestaticboolean hasPrePage(int currentPage){ 6a;v&5
return currentPage == 1 ? false : true; nFe%vu8a
} Rb(SBa
>J|]moSVA
privatestaticboolean hasNextPage(int currentPage, -hkQ2[Ew#
[:^-m8QC
int totalPage){ K|DWu8
return currentPage == totalPage || totalPage == 88c<:fK
C&++VRnm
0 ? false : true; ~rjTF!
} 5OoN!TEM
~+Z{Q25R
:VF<9@t
} lg047K
&Wf3~hmo
>5Wlc$bc
SZJ$w-<z
z<.?x%4O
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 Mwgu93?
lo'W1p
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 q5>v'ZSo
F@R1:M9*
做法如下: 3s"0SLS4
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 "*,XL
uv>
QXF
aAb=(7
的信息,和一个结果集List: tDr#H!2
3
java代码: K-&V,MI
ZNYH#mJX*
p$ bnK]
/*Created on 2005-6-13*/ [frq
'c
package com.adt.bo; ",{ibh)g$`
o[E_Ge}g8
import java.util.List; <(vCiH9~P
Q:ezifQ
import org.flyware.util.page.Page; 6%Be36<
V21njRS
/** YDGS}~m~Q
* @author Joa IF]lHB
*/ Cuc$3l(%
publicclass Result { Agrp(i"\@
kD[ r.Dma
private Page page; nI0[;'Hn,
Tr^nkD{
private List content; k1VT /u
V^Hu3aUx8
/** =}PdH`S
* The default constructor BcD&sQ2F
*/ )]#aa uC+
public Result(){ Z@Ae$ '9H
super(); 5XLs} :
} nk3y"ne7
*Sh^J+j
/**
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* The constructor using fields D/h/Y) Y
* Jjl`_X$CB
* @param page )Fb>8<%
* @param content /*|oL#hK
*/ fr!Pj(Q1
public Result(Page page, List content){ Y<0 4RV
this.page = page; HNL42\Kz!
this.content = content; )/t?!T.[
} 5s?Hxn
_{jjgQJ5
/** "`asFg
* @return Returns the content. zS]8V?`
*/ 5JhdVnT_
publicList getContent(){ :NJ(r(QG>
return content; V34hFa
} -[L!3jU
;l$ \6T
/** ITy/eZ"&:
* @return Returns the page. BPr^D0P
*/ U.{l;EL:T
public Page getPage(){ $wYFEz
return page; >hH0Q5aL
} ,ZS6jZ
pKS
{ 6P
/** {-BRt)L[
* @param content f3|@|'
;
* The content to set. fqu}Le
*/ 9_sA&2P{uV
public void setContent(List content){ rxme(9M
this.content = content; MQ)L:R`L
} sdCvG R e
TE )gVE]
/** .vG,fuf8
* @param page 7Ol}EPf#
* The page to set. H:H6b
*/ OCy0#aPRS
publicvoid setPage(Page page){ BnRN;bu
this.page = page; M,}|tsL
} c]B$i*t
} -YD+(c`l
lO:.OZu
Z0De!?ALV\
2DD:~Tbi
7 h y&-<
2. 编写业务逻辑接口,并实现它(UserManager, .d/:30Y
PQ|69*2G
UserManagerImpl) 7w;O}axI
java代码: 2BCtJ`S`
5sPywk{
LI)!4(WH
/*Created on 2005-7-15*/ tRpEF2
package com.adt.service; %zU`XVNN+
=uDgzdDyE
import net.sf.hibernate.HibernateException; <}6{{&mT4
Jgu94.;5
import org.flyware.util.page.Page; -CH`>
n41@iK2l
import com.adt.bo.Result; [7m1Q<
XBQ\_2>
/** I]!^;))
* @author Joa d2s OYCKe
*/ g]UBZ33y
publicinterface UserManager { ^TB>.c@ `*
*)]"27^
public Result listUser(Page page)throws fFjH "2WD
^KB~*'DN~s
HibernateException; P6,7]6bp
j]0^y}5f+s
} HyiFy7j
.}')f;jH5<
!se0F.K
W0jZOP5_.$
7kKy\W
java代码: H&b3{yOa
)rLMIk
u9=SpgB#
/*Created on 2005-7-15*/ f`>/
H!<2
package com.adt.service.impl; "!K'A7.^
|+ge8uu?C
import java.util.List; <\zCpkZ'B
D}3XFuZs_
import net.sf.hibernate.HibernateException; 6a}"6d/sTL
$>U#
W:
import org.flyware.util.page.Page; Cc?TSZ8[
import org.flyware.util.page.PageUtil; l:]Nn%U(>
YJxw 'U
>P
import com.adt.bo.Result; Ff^@~X+W<
import com.adt.dao.UserDAO; p#f+P?
import com.adt.exception.ObjectNotFoundException; AGA`fRVx
import com.adt.service.UserManager; =OJ;0 /$6
aj,)P3DJu
/** ~8`:7m?
* @author Joa Ut]+k+ 4
*/ *sQcg8{^
publicclass UserManagerImpl implements UserManager { _B2V "p
JFL>nH0mk.
private UserDAO userDAO; Wl^R8w#Z$
m"c :"I6
/** TaJB4zB
* @param userDAO The userDAO to set. 2S`?hxAL
*/ 1G~S|,8p
publicvoid setUserDAO(UserDAO userDAO){ aKF*FFX
this.userDAO = userDAO; Q-rL$%~='
} Y<\^7\[x
W&:[r/8wA
/* (non-Javadoc) zBf-8]"^
* @see com.adt.service.UserManager#listUser !e#xx]v3
Bqws!RM'&@
(org.flyware.util.page.Page) rg(lCL&:S
*/ Uh.Zi3X6}6
public Result listUser(Page page)throws !k$}Kj)I
vtJV"h?e"3
HibernateException, ObjectNotFoundException { N12:{U
int totalRecords = userDAO.getUserCount(); bt+,0\Vg5
if(totalRecords == 0) A{o 'z_zC
throw new ObjectNotFoundException uQLlA&I"
Y^"4?96
("userNotExist"); m8+(%>+7
page = PageUtil.createPage(page, totalRecords); l^NC]t
List users = userDAO.getUserByPage(page); D}Ilyk_uUw
returnnew Result(page, users); F="z]C;u
} V%HS\<$h
'k&?DZ!
} 7dh1W@\
~$O1`IT
'UM!*fk7C
SN+S6
Jeqxspn
T
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 %>Xr5<$:&
-U2mfW
询,接下来编写UserDAO的代码: tqOi
x/
3. UserDAO 和 UserDAOImpl: Ccfwax+
java代码: -'rj&x{Q)U
NnxM3*
kR.wOJ7'
/*Created on 2005-7-15*/ .
,NB( s`
package com.adt.dao; IKvBf'%-
z)F#u:t
import java.util.List; `NwdbKX
juToO
import org.flyware.util.page.Page; w5]"ga>Y
QF-)^`N
import net.sf.hibernate.HibernateException; .BTx&AqU
7x.%hRk
/** pt:;9hA
* @author Joa v@ONo?)
*/ +I|8Q|^SD
publicinterface UserDAO extends BaseDAO { eNySJf
&J"YsY
publicList getUserByName(String name)throws h\,5/ )Y
VlW9UF-W
HibernateException; 2]jPv0u
>L2*CV3p
publicint getUserCount()throws HibernateException; <D /a l9
ucg$Ed
publicList getUserByPage(Page page)throws 1q~LA[6
!"4w&bQ
HibernateException; sn k$^
$CtCOwKZ
} UFZ"C,
24@^{
}
1czG55 |
d5xxb _oE
y[HQBv
java代码: *)VAaGUX>
;?9A(q_Z
7#4%\f+'t
/*Created on 2005-7-15*/ "!&B4
package com.adt.dao.impl; 0*(K DDv
GXb47_b^
import java.util.List; `ypL]$cW
Md(JIlh3
import org.flyware.util.page.Page; M|CrBJv+F
2tr
:xi@
import net.sf.hibernate.HibernateException; 9\51Z:>
import net.sf.hibernate.Query; J6|JWp
C@@$"}%v2
import com.adt.dao.UserDAO; AF#_nK)@
O.:I,D&]
/** D?u`
* @author Joa SfI*bJo>V
*/ 9G:TW|)L[Q
public class UserDAOImpl extends BaseDAOHibernateImpl 'XfgBJF=
Md9l+[@
implements UserDAO { CV^0.
]xq::a{Oy
/* (non-Javadoc) ko[TDh$T5
* @see com.adt.dao.UserDAO#getUserByName Vq}r_#!Q
G:+16XCra
(java.lang.String) 7~.ZE
*/ {;RF
publicList getUserByName(String name)throws ^tE_LL+ji|
Z H-5Qy_
HibernateException { :::>ro*R
String querySentence = "FROM user in class 5-p.MGso
CX+9R3pa
com.adt.po.User WHERE user.name=:name"; g3rRhS
Query query = getSession().createQuery ltEF:{mLe#
{'IFWD. 5
(querySentence); {% F`%_{"
query.setParameter("name", name); npj/7nZj
return query.list(); ##~!M(c
} LP>UU ,Z
EhXiv#CZ
/* (non-Javadoc) e{t=>vry
* @see com.adt.dao.UserDAO#getUserCount() WFh@%j
*/ P0#`anUr1
publicint getUserCount()throws HibernateException { ;QidDi_s>
int count = 0; IxP^i{/1?
String querySentence = "SELECT count(*) FROM v' 0!= r
:VFTVmr
user in class com.adt.po.User"; "]<}Hy
Query query = getSession().createQuery D Q 5W6W
K`gc 4:A
(querySentence); {5 Kz' FT
count = ((Integer)query.iterate().next Qtnv#9%Vi
EW;1`x
()).intValue(); P!>g7X
return count; 3uO8v{`
} [0op)Kn
a 2E t,WA%
/* (non-Javadoc) a>(~ C'(<
* @see com.adt.dao.UserDAO#getUserByPage N?^_=KE@
.D3`'K3t{[
(org.flyware.util.page.Page) ^N{X "
*/ \P@S"QO
publicList getUserByPage(Page page)throws pE(sV{PD
lbofF==(
HibernateException { z`@z
String querySentence = "FROM user in class !OQuEJR
EOQaY
com.adt.po.User"; w06gY
Query query = getSession().createQuery #W^_]Q=5R'
\d5}5J]a&n
(querySentence); ~,G]glu8
query.setFirstResult(page.getBeginIndex()) HqRCjD
.setMaxResults(page.getEveryPage()); D8 wG!X
return query.list(); z"3H{ A
} |YXG(;-BS
[)k2=67
} `OLB';D
?Hk.|5A}
D9G0k[D,
85Dm8~
/gX%ABmS
至此,一个完整的分页程序完成。前台的只需要调用 ebD{ pc`&
%\l0-RA@<
userManager.listUser(page)即可得到一个Page对象和结果集对象 &&*wmnWCS{
[[$Mh_MD
的综合体,而传入的参数page对象则可以由前台传入,如果用 dL(4mR8
D0KELAcY
webwork,甚至可以直接在配置文件中指定。 ]eD [4Y\#t
E]?2!)mgce
下面给出一个webwork调用示例: d~,n_E$q;
java代码: yW:AVqE)t
)Kr(Y.w
$WJy?_c
/*Created on 2005-6-17*/ S}O5l}E
package com.adt.action.user; 0O^U{#*$I
xT/9kM&}L
import java.util.List; 0*{@E%9
?Cc$]
import org.apache.commons.logging.Log; ]svw
CPu C
import org.apache.commons.logging.LogFactory; zM)M_L
import org.flyware.util.page.Page; vo.EM1x
5 5a@)>h
import com.adt.bo.Result; <%(f9j
import com.adt.service.UserService; 7%X+O8
import com.opensymphony.xwork.Action; fA;x{0CAMX
m9uUDq#GJ
/** tPA"lBS !
* @author Joa HN^w'I'bp
*/ $*wu~
publicclass ListUser implementsAction{ Km%8Yw0+
sAf9rZt*'
privatestaticfinal Log logger = LogFactory.getLog Wl?<c
uw00
`dP? 2-Z
(ListUser.class); -IGMl_s
[10$a(g\x
private UserService userService; T<_+3kw
&KLvr|
private Page page; W0+u)gDDz
+ I?Qg
privateList users; E:%>0FE
Jr|K>
/* YALyZ.d
* (non-Javadoc) w:n(pLc<
* Un~]Q?w
* @see com.opensymphony.xwork.Action#execute() z)r8?9u
*/ \gjl^#;
publicString execute()throwsException{ /Lj%A
Result result = userService.listUser(page); qNhH%tYQ
page = result.getPage(); D~XU`;~u
users = result.getContent(); 7Z9.z4\
return SUCCESS; "hJ7 Vv_
} {P,>Q4N
.`b4h"g:
/** q=J9LQ
* @return Returns the page. -i2D#i'
*/ Z+OAs0}mV
public Page getPage(){ T<!\B]
return page; 3{6ps : w
} o$*bm6o
9@JlaY)0
/** jo]m12ps
* @return Returns the users. )j$b9ZBk
*/ p|xs|O6{
publicList getUsers(){ wV7@D[8
return users; ':5Trx
} R994R@gz
MYKs??]Y1
/** "h^A]t;qe
* @param page ,ZsYXW
* The page to set. 7g {g}
*/ Cij$GYkv
publicvoid setPage(Page page){ >aNbp
this.page = page; B:B0p+$I
} nD^{Q[E6=
]t8{)r
/** g|_HcaW
* @param users z0EjIYI[N
* The users to set. #p']-No
*/ L{4),65
publicvoid setUsers(List users){ f$~ _FX
this.users = users; {ILp[&sL
} \HBVNBY
!3O,DhH>MC
/** /F\>Z]
* @param userService ){?mKB5
* The userService to set. u?LW+o
*/ "H
wVK
publicvoid setUserService(UserService userService){ BT
y]!%r'
this.userService = userService; v4nvZ6
} 0(Yh~{
} oAIY=z
)*q7pO\cty
&<\4q
H8(0.IR
we6+2
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, (CKhY~,/u
Vu_7uSp,)
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 My'9S2Y8nv
&"@HWF
么只需要: 3:l: ~Vn
java代码: 5?#OR!N
jV(xYA3
1R^XWAb
<?xml version="1.0"?> nsM>% +o
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ze#rYN vo/
NgmO0H
1.0//EN" "http://www.opensymphony.com/xwork/xwork- \}]=?}(
9&|12x$
1.0.dtd"> wdN>KS2!
:pL1F)-*
<xwork> r_qncy,F
^=4I|+P,6.
<package name="user" extends="webwork- {ziYd;Ys1
=rf)yp-D
interceptors"> (Von;U
W>aQ
tT
<!-- The default interceptor stack name :8\*)"^E
1[fkXO{
--> -+j9X;h:
<default-interceptor-ref KNO*)\
op.PS{_t
name="myDefaultWebStack"/> 3[00-~&U
MX4 :e>dtd
<action name="listUser" k'WS"<-
6Y92&
class="com.adt.action.user.ListUser"> |ec(z
<param qY*%p
T_5*iwI
name="page.everyPage">10</param> ~#IWM+I
<result "G i+zkVm
YG}p$\R
name="success">/user/user_list.jsp</result> &UJTy'
</action> &k%wOz1vM
2ZTyo7P
</package> ArEH%e
)sY$\^'WY
</xwork> 9^b7jw
".*a)
)Ta]6
YKs^%GO+
\pBYWf
@@&@}IQcR1
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 f//j{P[
oJ4mxi@|#
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 Et6
;ZE<6;#3IP
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 's7 SZ$(
o%N0K
P}.yEta
K\Y6
cj
btB(n<G2#
我写的一个用于分页的类,用了泛型了,hoho I2Or&
_
lhIr]'?l
java代码: }{w_>!ee
+i q+
$J;=Ux)$
package com.intokr.util; W:;`
2jrX
import java.util.List; 9^C!,A{u4
^c[CyZ:a
/** =w;xaxjL
* 用于分页的类<br> Rm[rQ}:
* 可以用于传递查询的结果也可以用于传送查询的参数<br> i+T0}M<
* kHo;9j-U
* @version 0.01 o}AqNw60v
* @author cheng 2!~>)N
*/ Y+PvL|`O
public class Paginator<E> { ?SsRN jeL
privateint count = 0; // 总记录数 S*DBY~pZy
privateint p = 1; // 页编号 [<3Q$*Ew
privateint num = 20; // 每页的记录数 EiIFVP
privateList<E> results = null; // 结果 [&]YVn>kj
{*5;:QnT
/** 7:R{~|R
* 结果总数 5>z:[OdY*
*/ lG[
)8!:+
publicint getCount(){ sP8-gkkor
return count; 6&xW9' 6b:
} W0uM?J\O
f'zFg["aZS
publicvoid setCount(int count){ \PtC
this.count = count; XR=c
8f
} E6wST@r
@u'27c_<d3
/** /iJcy:J
* 本结果所在的页码,从1开始 37M[9m|D*
* M@LaD 5
* @return Returns the pageNo. N-?|]4e/
*/ 4[f7X4d$
publicint getP(){ Pi]s<3PL
return p; J!^~KN6[
} OD@@O9
|2t7mat
/** qeO6}A"^|
* if(p<=0) p=1 %Cbc@=k
* uK&wS#uY
* @param p h+'eFAZ
*/ $xn%i\
publicvoid setP(int p){ (=&bo p
if(p <= 0) J/P@m_Yx
p = 1; +EB,7<5<
this.p = p; 0.+Z;j
} g9r5t';
?PxYS%D_L
/** O'sr[
* 每页记录数量 d=5}^v#4
*/ WUOPYYW<o
publicint getNum(){ $P}]|/Yb
return num; cwD*>[j
} t%YX-@
/Geks/
/** jiB>.te
* if(num<1) num=1 X=c
,`&^
*/ m=y,_Pz>U
publicvoid setNum(int num){ z1KC$~{O
if(num < 1) u{lDof>
num = 1; *$Wx*Jo
this.num = num; Kd[`mkmS
} ,DUQto
A
=Az[
/** `GN5QLg#}0
* 获得总页数 GHsdLe=t0#
*/ !vo '8r?&
publicint getPageNum(){ [F-u'h< *l
return(count - 1) / num + 1; >p#d;wK4_
} U@t?jTMBkO
VEYKrZA
/** uB&I56
* 获得本页的开始编号,为 (p-1)*num+1 cS ;=_%~
*/ BHBT=,sI
publicint getStart(){ .$s|T
return(p - 1) * num + 1; nF
y7gA|
} xbH!:R;
$8 ww]}K
/** A5H8+gATK
* @return Returns the results. xA1pDrfC/
*/ q}24U3ow
publicList<E> getResults(){ ]=XL9MI
return results; @_:?N(%(
} v&/-&(+
J3}C T
public void setResults(List<E> results){ m_ONsZHy
this.results = results; jE5
9h
} Fu$Gl$qV?%
]` Gz_e
public String toString(){ `[u>NEb
StringBuilder buff = new StringBuilder !";$Zu
27i<6PAC[A
(); NTX+7<
buff.append("{"); [-94=|S @
buff.append("count:").append(count); iW%0pLn
buff.append(",p:").append(p); ,7$uh):
buff.append(",nump:").append(num); Dq1XZ%8
buff.append(",results:").append 3:gO7Uv
v@1Jhns
(results); Hw. @Le>
buff.append("}"); `,]PM)iC
return buff.toString(); -#z'A
} vh3iu+
Evgq}3
} 0JL6EL>_
k.f:nv5JO
iP\&fZY_