Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 kMzDmgoxNg
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 p8s%bPjK
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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 =RWY0| f
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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 01aw+o
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分页支持类: $WE_aNfja
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java代码: <T'fJcR
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package com.javaeye.common.util; /f.
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import java.util.List; s!Id55R]
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publicclass PaginationSupport { x )q$.u+
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publicfinalstaticint PAGESIZE = 30; g*9&3ov
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privateint pageSize = PAGESIZE; f4X}F|!h
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privateList items; +~
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privateint totalCount; zZ<~yi3A9
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privateint[] indexes = newint[0]; D*HK[_5
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privateint startIndex = 0; N0
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public PaginationSupport(List items, int Jju?v2y`
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totalCount){ l29AC}^
setPageSize(PAGESIZE); ]?jmRk^.
setTotalCount(totalCount); -x/g+T-
setItems(items); <PO-S\N
setStartIndex(0); 1-! |_<EW1
} kl&_O8E+K
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public PaginationSupport(List items, int d7kv
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h*
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totalCount, int startIndex){ wz:w6q
setPageSize(PAGESIZE); }u5J<*:bZ
setTotalCount(totalCount); 7w0=i Z>K
setItems(items); D{t0OvQag
setStartIndex(startIndex); h!hv{c
} +hT9V1'-D
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public PaginationSupport(List items, int >R/^[([;]
r^\Wo7q
totalCount, int pageSize, int startIndex){ 0wETv
setPageSize(pageSize); 8,m:
setTotalCount(totalCount); 8HSGOs =8
setItems(items); F|WH=s3
setStartIndex(startIndex); okW'}@jD
} Pb :6nH=
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publicList getItems(){ G~4|]^`g
return items; ht5:kt`F
} 7nPm{=BG
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publicvoid setItems(List items){ m)<N:|
this.items = items; & *&
} 'Cywn^Ym#
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publicint getPageSize(){ abV,]x&.0
return pageSize; 7aNoqS+
} %A(hmC
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publicvoid setPageSize(int pageSize){ A5dH*< }
this.pageSize = pageSize; &cx]7:;
} w?c~be$
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publicint getTotalCount(){ k1WyV_3
return totalCount; ]0p*EB=C*
} 23UXOY0BW
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publicvoid setTotalCount(int totalCount){ 3j$,x(ua9
if(totalCount > 0){ VzFzVeJ
this.totalCount = totalCount; dU"C=c(w\
int count = totalCount / _k
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xJ|Z]m=d
pageSize; "}UYsXg
if(totalCount % pageSize > 0) M$LzV}k
count++; Yf^/YLLS
indexes = newint[count]; 7)3cq}]O
for(int i = 0; i < count; i++){ }Qvoms<k
indexes = pageSize * !]WC~#|{B
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i; B.[5N;c
} ["?WVXCF8|
}else{ < 'qtqUL\
this.totalCount = 0; kI$p~
} M7IQJFra
}
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publicint[] getIndexes(){ s}Sxl0
return indexes; GEf[k OQ
} 04<T2)QgK
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publicvoid setIndexes(int[] indexes){ }=."X8zOI8
this.indexes = indexes; 9]/ju
} W.U|mNJ$
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publicint getStartIndex(){ o!t1EPJE*
return startIndex; -wV0Nv(V8
} 38q0iAH
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publicvoid setStartIndex(int startIndex){ g7W\
&
if(totalCount <= 0) I*)eP||
this.startIndex = 0; ma4r/8Q
elseif(startIndex >= totalCount) gbRdng7(}
this.startIndex = indexes
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[indexes.length - 1]; U^X8{,8O
elseif(startIndex < 0) -?<L"u
this.startIndex = 0; 5Bc)QKh`l|
else{ _`Sz}Yk
this.startIndex = indexes #3u471bp
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[startIndex / pageSize]; C!" .[3
} 6ypqnOTr
} V_7xXuM/
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publicint getNextIndex(){ tlFc+3
int nextIndex = getStartIndex() + IsCJdgG
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pageSize; $$G^#t1=XZ
if(nextIndex >= totalCount) 8m"5J-uIi
return getStartIndex(); P%Ux-0&
else *8CE0;p'k
return nextIndex; Q,`Y
} 6.'+y1yS)
|]H2a;vUJR
publicint getPreviousIndex(){ Wh>Y_ k
int previousIndex = getStartIndex() - 9qQFIw~S
@V-CG!
pageSize; &_E*]Sj\
if(previousIndex < 0) #0 WO~wL
return0; cBA2;5E
else $T0|zPK5
return previousIndex; $rC`)"t
} ]g;K_>@
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} |KC3^
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抽象业务类 i=<(fq
java代码: h(G(U_V-Od
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/** P5P<-T{-c
* Created on 2005-7-12 n1W}h@>8
*/ yx }Z:t
package com.javaeye.common.business; _n{6/
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import java.io.Serializable; }J$PO*Q@'
import java.util.List; QrPWS-3~!
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import org.hibernate.Criteria; (Qq$ql27
import org.hibernate.HibernateException; a~~ "2LE`
import org.hibernate.Session; V*'9yk"
import org.hibernate.criterion.DetachedCriteria; uyG4zV\h*
import org.hibernate.criterion.Projections; ;@d<*
import ZdHWSfO)O
&/, BFx"
org.springframework.orm.hibernate3.HibernateCallback; 3)g1e=\i$
import X6<HNLgra
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org.springframework.orm.hibernate3.support.HibernateDaoS ?t}[Wi}7
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upport; uYMW5k_,>
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import com.javaeye.common.util.PaginationSupport; Qg
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public abstract class AbstractManager extends n5]<|>Uvx
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HibernateDaoSupport { >)pwmIn<
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privateboolean cacheQueries = false; \aUbBa%!
% NS]z ;G
privateString queryCacheRegion; +TAm9eDNV
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publicvoid setCacheQueries(boolean (lPNMS|V
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cacheQueries){ s_Dl8O4u
this.cacheQueries = cacheQueries; i]$7w! r&
} 65J'uN
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publicvoid setQueryCacheRegion(String u X0wg
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queryCacheRegion){ xSOL4
this.queryCacheRegion = {@,
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queryCacheRegion; U0N[~yW(t1
}
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publicvoid save(finalObject entity){ d$2{_6
getHibernateTemplate().save(entity); ?n@PZL= ]
} (%fGS.TR
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@g
publicvoid persist(finalObject entity){ Mc6Cte]3|
getHibernateTemplate().save(entity); nC&rQQFF
} @xkM|N?
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publicvoid update(finalObject entity){ b]g.>$[nX
getHibernateTemplate().update(entity); 5^d%+*l;q
} cq9Q7<&MF
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publicvoid delete(finalObject entity){ _RmE+ Xg2
getHibernateTemplate().delete(entity); >Ia(g0
} +NXj/
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publicObject load(finalClass entity, X"1<G3m4
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finalSerializable id){ l9L;Tjj
return getHibernateTemplate().load 1VZ>*Tl
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(entity, id); 9H)uTyuNi
}
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publicObject get(finalClass entity, J/=A f
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finalSerializable id){ Vut.oB$
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return getHibernateTemplate().get R{rV1j#@!a
8
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(entity, id); IIR?@/q
} 2b"5/$|6
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publicList findAll(finalClass entity){ nRE}F5k
return getHibernateTemplate().find("from 1aDDl-8,
yR$_$N+E
" + entity.getName()); ( gFA? aD<
} &sNID4FR
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publicList findByNamedQuery(finalString T8(wzs
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namedQuery){ LK%B6-;~-
return getHibernateTemplate N*MR6~z4
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().findByNamedQuery(namedQuery); @}Z/{Z[@
} eJA{]^Zf
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publicList findByNamedQuery(finalString query, 2Ee1mbZVw8
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finalObject parameter){ A-u5
return getHibernateTemplate ^MW%&&,BL
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().findByNamedQuery(query, parameter); 5q#|sVT7R
} 3.H-G~
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publicList findByNamedQuery(finalString query, wEbs E<</
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finalObject[] parameters){ wE \c?*k
return getHibernateTemplate K{P#[X*5
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().findByNamedQuery(query, parameters); bLzuaNa'
} 9"RfL7{
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publicList find(finalString query){ I`kp5lGD2
return getHibernateTemplate().find h3IkOh4|h
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(query); W>bW1h
} ;wxt<
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publicList find(finalString query, finalObject XXcf!~uO
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parameter){ }gi'%e
return getHibernateTemplate().find Hu7zmh5FF
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(query, parameter); K-C,+ eI
} d@4!^vD;
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public PaginationSupport findPageByCriteria 3/=QZ8HA&-
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(final DetachedCriteria detachedCriteria){ \=V[ba:q
return findPageByCriteria 5(7MQuRR
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); C+?s~JL
} }2A1Yt:^P
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public PaginationSupport findPageByCriteria l_-n&(N2<[
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(final DetachedCriteria detachedCriteria, finalint }t3FAy(%
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startIndex){ >m1V9A
return findPageByCriteria z8 ;#H
tr
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(detachedCriteria, PaginationSupport.PAGESIZE, ?mR[A`J58
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startIndex); `A _8nW)
} Z"|P(]A
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public PaginationSupport findPageByCriteria M .`
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(final DetachedCriteria detachedCriteria, finalint &qP-x98E?
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pageSize, ?b7g9 G4
finalint startIndex){ ~)a;59<$
return(PaginationSupport) kF,\bM
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getHibernateTemplate().execute(new HibernateCallback(){ G+X[R^RD
publicObject doInHibernate EN)A"
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(Session session)throws HibernateException { }`N2ZxC0AQ
Criteria criteria = kTZx-7~
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detachedCriteria.getExecutableCriteria(session); .`&/QiD
int totalCount = `$sY^EX
+'qX
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((Integer) criteria.setProjection(Projections.rowCount M1^C8cz
^_KD&%M6
()).uniqueResult()).intValue(); ~d%;~_n
criteria.setProjection %|(?!w7
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(null); 3[=`uO0\7
List items = V9E6W*IE
;\.JV '
criteria.setFirstResult(startIndex).setMaxResults pP0Vg'V
?S&w0}R
(pageSize).list(); 6Z7pztk
PaginationSupport ps = xeHb89GnoQ
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new PaginationSupport(items, totalCount, pageSize, %+xwk=%*
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startIndex); \5[D7}
return ps; uPFHlT
} <m>l-]
}, true); wVp4c?s
} ]`@]<6
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public List findAllByCriteria(final zvGK6qCk
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DetachedCriteria detachedCriteria){ o3F|#op
return(List) getHibernateTemplate ~n/Aq*
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().execute(new HibernateCallback(){ j6e}7
publicObject doInHibernate fQQsb 5=i
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(Session session)throws HibernateException { |)-|2cPRur
Criteria criteria = %'"HGZn b
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detachedCriteria.getExecutableCriteria(session); $7UoL,N>
return criteria.list(); 6QII&Fg
}
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}, true); Z cm<Fw
} Vd%v_Ek
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public int getCountByCriteria(final 0iJ!K;A2%
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DetachedCriteria detachedCriteria){ X&(<G
Integer count = (Integer) zJ;>.0
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getHibernateTemplate().execute(new HibernateCallback(){ Zk=*7?!!
publicObject doInHibernate X(k{-|9]
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(Session session)throws HibernateException { 1~2R^#rm
Criteria criteria = MzQ\rg_B7
c~}={4M]
detachedCriteria.getExecutableCriteria(session); OXHvT/L`
return OM.k?1%+M
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criteria.setProjection(Projections.rowCount -AjH}A[!
bLgL0}=n
()).uniqueResult(); *u>lx!g
} Kt
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}, true); B< |VeU
return count.intValue(); mn]-rTr
} ZFS7{:
} mZ~ qG5@/F
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用户在web层构造查询条件detachedCriteria,和可选的 ^0^(
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Sd},_Kh
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PaginationSupport的实例ps。 d%0+i/p
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ps.getItems()得到已分页好的结果集 }N3V5cab
ps.getIndexes()得到分页索引的数组 dY} pN"
ps.getTotalCount()得到总结果数 [oV{83f
ps.getStartIndex()当前分页索引 KOjluP
ps.getNextIndex()下一页索引 'b^l'KN:S
ps.getPreviousIndex()上一页索引 XCDSmZ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 =SAV|
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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 ZK6Hvc0
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一下代码重构了。 1dFa@<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`(~OO
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首先,为了实现分页查询,我封装了一个Page类: u$%A#L[
java代码: )RN<GW'
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/*Created on 2005-4-14*/ xRum*}|4
package org.flyware.util.page; !aPD}xCH#
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/** _;hf<|c
* @author Joa
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* tx"LeZZ
*/ ~.^AL}zm_
publicclass Page { VWx]1\
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/** imply if the page has previous page */ %'bJ:
privateboolean hasPrePage; s"%lFA"-
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/** imply if the page has next page */ HeLG?6
privateboolean hasNextPage; qnChM;)
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/** the number of every page */ s$w;q\1z
privateint everyPage; !E2W\chi
}rq9I"/L
/** the total page number */ "l7NWqfB
privateint totalPage; e(?]SU|
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/** the number of current page */ k7@t{Cu0D&
privateint currentPage; ]y#3@
\?**2{9&)
/** the begin index of the records by the current w_hHfZ9E
*bd[S0l
query */ OhVs#^
privateint beginIndex; nhT-Ido
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/** The default constructor */ )5_jmW`n
public Page(){ =Yz'D|=t
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}
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/** construct the page by everyPage ]QVNn?PA8
* @param everyPage I_1e?\
* */ /,@p\Ae5
public Page(int everyPage){ -VxDNT}Tr
this.everyPage = everyPage; nKoiG*PI
} :,B7-kBw
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/** The whole constructor */ F@ Swe
public Page(boolean hasPrePage, boolean hasNextPage, zK|i='XSf
/FD5G7ES
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int everyPage, int totalPage, }%7NF*
int currentPage, int beginIndex){ 3 ZEB
this.hasPrePage = hasPrePage; */:uV
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this.hasNextPage = hasNextPage; 3cdTed-MIh
this.everyPage = everyPage; Fz#X=gmG
this.totalPage = totalPage; ':{>a28=
this.currentPage = currentPage; PHOP%hI$
this.beginIndex = beginIndex; ;oZ)Wt
} js iSg/
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/** R^?/' dr
* @return LUB${0BrA
* Returns the beginIndex. W-NDBP:
*/ f+8wl!M+6
publicint getBeginIndex(){ X+UJzR90
return beginIndex; ;AO#xv+#
} >leU:7
}PTV] q%
/** jCbV,0)^
* @param beginIndex nRyU]=-X
* The beginIndex to set. VD_$$Gn*q
*/ zR2B-
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publicvoid setBeginIndex(int beginIndex){ X}+>!%W!}
this.beginIndex = beginIndex; wF((
} ULMu19>
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/** yKO`rtP
* @return DI+fwXeg
* Returns the currentPage. |*}4 m'c
*/ >=[(^l
publicint getCurrentPage(){ g$b<1:8
return currentPage; j4qJ.i
} yUpgoX(6
;q*e=[_DF
/** Y1]n^
* @param currentPage 6i1LjLB
* The currentPage to set. O)[1x4U
*/ q
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publicvoid setCurrentPage(int currentPage){ ZIQ
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this.currentPage = currentPage; oH_;4QU4y
} rx] @A
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/** p6;OL@\~
* @return xL\0B,]
* Returns the everyPage. 3f,hw5R
*/ g*_cPU0~m
publicint getEveryPage(){ )c)vTZy
return everyPage; 1,% R;7J=g
} >k (C
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/** !wNr3LG
* @param everyPage NfjE`
* The everyPage to set. PK `D8)=u
*/ _no*k?o*
publicvoid setEveryPage(int everyPage){ V=o
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this.everyPage = everyPage; "$YJX1u3
} T( U_
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/** e]zBf;9J
* @return L6|oyf
* Returns the hasNextPage. :g Wu9Y|{
*/ iMDM1}b
publicboolean getHasNextPage(){ .nx2";oi
return hasNextPage; woK&q 7Vn
} pSdI/Vj'=
+[\FD; >
/** Z/Dx,zIR
* @param hasNextPage J;8IY=
* The hasNextPage to set. P*3BB>FO
*/ x"~8*V'0
publicvoid setHasNextPage(boolean hasNextPage){ :LW4E9O=H
this.hasNextPage = hasNextPage; Nh_Mz;ITuu
} hG12ZZ D
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/** jtW!"TOY
* @return CVL3VT1j0
* Returns the hasPrePage. 3u*4o=4e
*/ L.*M&Ry
publicboolean getHasPrePage(){
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return hasPrePage; r\'A
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} 1mOh{:1u
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/** z[L8$7L
* @param hasPrePage l5!|I:/*;
* The hasPrePage to set. 7:plQ!7^
*/ >UiYL}'br6
publicvoid setHasPrePage(boolean hasPrePage){ SB H(y)
this.hasPrePage = hasPrePage; :LF?
} XDOY`N^L
]hk
/** CQF:Rnb
* @return Returns the totalPage. zPn+V7F
* saBVgSd
*/ G|!Tj X7s
publicint getTotalPage(){ PUp6Q;AdQ
return totalPage; EE&K0<?T|:
} +"
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/** Cjm`|~&e+
* @param totalPage *2pt%eav
* The totalPage to set. <\rT%f}3^
*/ yVU^M?`#
publicvoid setTotalPage(int totalPage){ *+Ek0M
this.totalPage = totalPage; P{kur} T
} ]7W&JKmA&
N7b8m?!
} +"\sc;6m.
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7zXvnxYE
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x
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 V,lOt4b
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个PageUtil,负责对Page对象进行构造: o[Q MT P
java代码: 44ek
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/*Created on 2005-4-14*/ u%&`}g
package org.flyware.util.page; &FMc?wq
TV)h`\|Z*
import org.apache.commons.logging.Log; %a>&5V
import org.apache.commons.logging.LogFactory; 2V-
16Q'%
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/** |GdUL%1hnC
* @author Joa -u6bAQ
* 8g@<d^8@
*/ c,np2myd
publicclass PageUtil { |HiE@
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privatestaticfinal Log logger = LogFactory.getLog u1J0$
jD$,.AVvz
(PageUtil.class); Uf:`
>{q]&}^U
/** J{.{f
* Use the origin page to create a new page (yH'{6g\
* @param page ;v}GJ<3
* @param totalRecords :}He\V
* @return
: |>h7v
*/ \r/rBa\
publicstatic Page createPage(Page page, int LA!?H]
"3X2VFwoJ
totalRecords){ H*d9l2,KZS
return createPage(page.getEveryPage(), `l\7+0W
<wk!hTmW
page.getCurrentPage(), totalRecords); lEH65;Nh*
} Z+*9#!?J
kjTduZ/3"
/** 4`4kfiS$
* the basic page utils not including exception OV1_|##LC
TJ10s%,V
handler Gt\lFQ
* @param everyPage { }:#G
* @param currentPage D>`xzt '.6
* @param totalRecords cVXLKO
* @return page p2hB8zL
*/ h0(BO*cy
publicstatic Page createPage(int everyPage, int OSRp0G20k\
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currentPage, int totalRecords){ dH;8mb|#'
everyPage = getEveryPage(everyPage); ty8q11[8
currentPage = getCurrentPage(currentPage); 216 RiSr*
int beginIndex = getBeginIndex(everyPage, y`L>wq,KU
4-l8,@9
currentPage); ]3D0R;
int totalPage = getTotalPage(everyPage,
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qEyyT[:
totalRecords); T(#J_Y
boolean hasNextPage = hasNextPage(currentPage, R"-mKT}
h){0rX@:&
totalPage); 5[8xV%>;
boolean hasPrePage = hasPrePage(currentPage); 1jx:;j
a4mn*,
returnnew Page(hasPrePage, hasNextPage, .u)X3..J
everyPage, totalPage, ;dkYf24
currentPage, TYy?KG>:'
IQAZuN"<
beginIndex); B~'vCuE
} ]tim,7s
WQx?[tW(U
privatestaticint getEveryPage(int everyPage){ Q{O+
return everyPage == 0 ? 10 : everyPage; #oS<E1
} F3y9@dA]
lXx=But
privatestaticint getCurrentPage(int currentPage){ ]MqMQLG0t
return currentPage == 0 ? 1 : currentPage; &9.C l;I
} fJ=0HNmX
ADz ^\
privatestaticint getBeginIndex(int everyPage, int 6`&a&%,O
V )3KS-
currentPage){ c_dVWh e
return(currentPage - 1) * everyPage; %h hfU6[
} w0[6t#$F
<kfnpB=
privatestaticint getTotalPage(int everyPage, int UBv,=v
$r^GE
totalRecords){ aFl;BhM
int totalPage = 0; +UC G0D
<!&[4-;fU
if(totalRecords % everyPage == 0) J9..P&c\
totalPage = totalRecords / everyPage; $CRm3#+
~
else 9d>-MX'
totalPage = totalRecords / everyPage + 1 ; #{6{TFx\
q?H|o(
return totalPage; EW}Bz h>b
} cA&9e<
H!@kO]?n
privatestaticboolean hasPrePage(int currentPage){ R1s`z|?
return currentPage == 1 ? false : true; b\ X@gq
} FK^p")i
d}Xr}
privatestaticboolean hasNextPage(int currentPage, *~2,/D
5v[*:0p'
int totalPage){ N(O9&L*4fm
return currentPage == totalPage || totalPage == 7( #:GD
&]Q@7Nl7:l
0 ? false : true; @Rg/~\ K
} [Hx0`Nc K
J;S
(>c
m\;R2"H%
} f<-Jg
# ' =a=8-$
@MoKWfc
;^+\K-O]c
''|W9!
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。 <g-9T -Ky
8aZ=?_gvT
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 ] ;KJ6
N[?N5~jG
做法如下: '-wj9OU
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 -7SAK1c$
PoNi"Pv
的信息,和一个结果集List: :{{F *FM;
java代码: x;w6na
?}qttj
MlcR"gl*
/*Created on 2005-6-13*/ 2{D{sa
package com.adt.bo; z Eq GD2"
iyN:%ofh
import java.util.List; xP_cQwm`1
ih)zG
import org.flyware.util.page.Page; PYiU_
3s5z
UT;
/** 0Vj4+2?L5;
* @author Joa hZdoc<
*/ Y1L[;)H n
publicclass Result { c>,KZ!
B{/R: Hm
private Page page; WJ$bf(X*
PvzcEV
private List content; fJ5iS
_uWpJhCT
/** 9eR-
* The default constructor y?rPlA_
*/ 6wPaJbRtaM
public Result(){ -O1>|y2rU
super(); tankR9(o
} H=@}=aPf
kd>hhiz|
/** !6n_}I-W
* The constructor using fields VQ"hUX8
* j@=%_^:i
* @param page H[{F'c[e
* @param content 3("_Z%
*/ ^tqzq0
public Result(Page page, List content){ $}RJ,%~'x
this.page = page; t
4PK}>QW
this.content = content; %huRsQ%}
} E08klC0
NYyh|X:m
/** t,QyfN
* @return Returns the content. ccNd'2P
*/ *,3SGcYdJj
publicList getContent(){
S\LkL]qx
return content; W_||6LbZy
} bmJ5MF]_fG
;ZH3{
/** }d&_q7L@@6
* @return Returns the page. N<|@ymi
*/ }e!x5g
public Page getPage(){ "*($cQ$v
return page; $()5VMb
} RzxNbeki[W
:S.9eFfa
/** OJ,`
* @param content j`oy`78O
* The content to set. J3,fk)
*/ x8wD0D
public void setContent(List content){ ^]7}YF2|
this.content = content; ao%NK<Lt
} Qi^Z11
w0ht
/** mlixIW2
* @param page &]8P1{
* The page to set. oT^{b\XN
*/ T29Dt
publicvoid setPage(Page page){ b8~Bazk
this.page = page; e]`[yf
} `JOOnTenQ
} 1|RANy
os,* 3WO
~kShq%
@<&5J7fb
iEd\6EZ
2. 编写业务逻辑接口,并实现它(UserManager, >Nvjl~o5
_I:~@
UserManagerImpl) txW{7[w+,
java代码: J!0DR4=Xi
q-.,nMUF
Id'X*U7Q
/*Created on 2005-7-15*/ H(bs$C4F
package com.adt.service; GKOD/,
Rec6c&5_
import net.sf.hibernate.HibernateException; s8-<m,*
.l>77zM6
import org.flyware.util.page.Page; f%Ns[S~ r
?!9)q.bW
import com.adt.bo.Result; .Si,dc\
\Z]UA&v_
/** PUF/#ck
* @author Joa f47Od-\-
*/ AmaT0tzJC
publicinterface UserManager { :E_g"_
/a^1_q-bX
public Result listUser(Page page)throws crqpV F]1]
d{XO/YQw
HibernateException; L[^9E'L$
)=5ng-
} v5By :z
nN*w~f"
S/^"@?z,vE
5|l* `J)
K%"5ImM
java代码: MOsl_^c
\]=7!RQ\
Q?3Gk%T0[
/*Created on 2005-7-15*/ F">Qpgt
package com.adt.service.impl; 2Tfz=7h$
^~G8?]w
import java.util.List; 29!q!g |
Cg&e(
import net.sf.hibernate.HibernateException; VG,u7A*Z#
V>ieh2G(
import org.flyware.util.page.Page; /x5rf
import org.flyware.util.page.PageUtil; !'mq ?C=
kBYNf =
import com.adt.bo.Result; %1O;fQL
import com.adt.dao.UserDAO; 11<Qxu$rL
import com.adt.exception.ObjectNotFoundException; #Yr9AVr}K
import com.adt.service.UserManager; .Jt[(;
BB~OqZIP
/** Hz.(qW">5*
* @author Joa sB^<6W!`(
*/ |
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publicclass UserManagerImpl implements UserManager { &K/ya7
#bl6sa{E
private UserDAO userDAO; )=AHf?hn
UVw~8o9s
/** dgA-MQ5{
* @param userDAO The userDAO to set. l~6?kFy9h
*/ 9T|IvQK8
publicvoid setUserDAO(UserDAO userDAO){ .a._NW
this.userDAO = userDAO; r :F
} 5e$~)fL
?pn}s]*/
/* (non-Javadoc) rb1`UG"h$
* @see com.adt.service.UserManager#listUser $% 1vW=d
{_S}H1,
(org.flyware.util.page.Page) yto,>Utzg
*/ 'Y56+P\u
public Result listUser(Page page)throws mnmP<<8C,
WHjUR0NZ
HibernateException, ObjectNotFoundException { H63,bNS s
int totalRecords = userDAO.getUserCount(); |1b_3?e
if(totalRecords == 0) X LL/4 )
throw new ObjectNotFoundException ;PjQt=4K
.h9l7
nZt
("userNotExist"); -5T=:2M
page = PageUtil.createPage(page, totalRecords); :{oZ ~<
List users = userDAO.getUserByPage(page); (;q\}u
returnnew Result(page, users); G(~;]xNW+
} co9 .wB@
`67[O4$<
} Hd,p!_
]p;FZ4-T
f-5:wM&
%K>.lh@
1qf!DMcdZ
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 # g_Bx
jcI&w#re
询,接下来编写UserDAO的代码: }S3qBQTYL
3. UserDAO 和 UserDAOImpl: sgO'wXcoP
java代码: 7DIIx}A
*Mw_0Y
L5qwWvbT
/*Created on 2005-7-15*/
2'5 ]~
package com.adt.dao; A?`jnRo=\
HO[wTB|D]
import java.util.List; rtL}W__
!}4MN:r
import org.flyware.util.page.Page; 2 ho>eRX
WdnIp!
import net.sf.hibernate.HibernateException; ZKXo-~=>
c7M%xGrP
/** ($LLl;1
* @author Joa Y}[ c^$S
*/ k<cgO[m
publicinterface UserDAO extends BaseDAO { H_0/f8GwnG
2hee./F`
publicList getUserByName(String name)throws &m[Qn!>i6
P0$e~=Q^4
HibernateException; Y&
F=t/U2
JR@.R
,rII
publicint getUserCount()throws HibernateException; OQ,NOiNkap
cetvQAGXY
publicList getUserByPage(Page page)throws yB3;
^mb[j`CCt
HibernateException; o}<4*qlI
]r-C1bKD`
} z
Nl ,
YFTjPBV
Fh*j#*oe
NNF>Xa`9,
4<x'ocKlD
java代码: b9"jtRTdz
&<+ A((/i
nN~~cV
/*Created on 2005-7-15*/ 7c;9$j
package com.adt.dao.impl; YhRWz=l
R@wjccu
import java.util.List; <BW[1h1k5_
-kS~xVS|
import org.flyware.util.page.Page; cS. -7
LPwT^zV&N
import net.sf.hibernate.HibernateException; NWd<+-pC6
import net.sf.hibernate.Query; .7
asW(
z`Hy'{1
import com.adt.dao.UserDAO; ]7Fs$y.
&h~Xq^
/** Pub0IIs
* @author Joa g!i45-n3gt
*/ qClHP)<
public class UserDAOImpl extends BaseDAOHibernateImpl r|*&GHo L
KK,Z"){
implements UserDAO { 2..,Sk
N-g8}03
/* (non-Javadoc) BI:k#jO!
* @see com.adt.dao.UserDAO#getUserByName [I:KpAd/
]?h`:,]
(java.lang.String) {}o>{&X
*/ ?+c`]gO7N
publicList getUserByName(String name)throws \]9.zlB
CAT.4GM
HibernateException { Jd,)a#<j
String querySentence = "FROM user in class ?k[p<Uo
F/1#l@qN
com.adt.po.User WHERE user.name=:name"; hCYQGx0
Query query = getSession().createQuery Y:ldR
jEz+1Nl)
(querySentence); lZ&]|*>
query.setParameter("name", name); &t(0E:^TRU
return query.list(); 93IFcmO.H@
} 7B3w\
O8U<{jgAG
/* (non-Javadoc) jxgj,h"}9`
* @see com.adt.dao.UserDAO#getUserCount()
LzDI0a.
*/ %~NH0oFO
publicint getUserCount()throws HibernateException { -xg2q
V\c
int count = 0; qEUT90
String querySentence = "SELECT count(*) FROM Y`6rEA0
qP!P
+'B
user in class com.adt.po.User"; CJaKnz
Query query = getSession().createQuery x\s,= n3z
~e@>zoM'^
(querySentence); `A/j1UWJ
count = ((Integer)query.iterate().next kHc<* L_V
Xl |1YX1&m
()).intValue(); M!M!Ni
return count; l_/C65%.:
} 8iC:xcN3
1on'^8]0
/* (non-Javadoc) HjWq[[Nz
* @see com.adt.dao.UserDAO#getUserByPage .wrL3z_
]7AX%EG3
(org.flyware.util.page.Page) 1U\$iy8}
*/ t@?u
publicList getUserByPage(Page page)throws ps:f=6m2
io4A>>W==/
HibernateException { >n.z)ZJ
String querySentence = "FROM user in class qBk``!|s]
w8~K/>!f
com.adt.po.User"; [IM%b~j(^
Query query = getSession().createQuery &217l2X
/
dpN@#w
(querySentence); }ublR&zlp
query.setFirstResult(page.getBeginIndex()) 8_\W/I!7b
.setMaxResults(page.getEveryPage()); VU!w!GN]Y
return query.list(); `kN#4p
} \Mx
JH[
j;P+_Hfe/E
} t]_S
`m%dX'0E
W,hWOO
y)J(K*x/$
0??Yr
至此,一个完整的分页程序完成。前台的只需要调用 T>]sQPg
%EbiMo ]3B
userManager.listUser(page)即可得到一个Page对象和结果集对象 ?H;{~n?
l`n5~Fs
的综合体,而传入的参数page对象则可以由前台传入,如果用 ddpl Pzm#
f$xhb3Qn
webwork,甚至可以直接在配置文件中指定。 !)H*r|*[
+$beo2x6
下面给出一个webwork调用示例: )BV=|,j
java代码: MR9/Y:Nm
whkJ pK(
s^C;>
/*Created on 2005-6-17*/ Z^6#4Q]YC
package com.adt.action.user; z&'f/w8
t3F?>G#y
import java.util.List; c;V D}UD'
z%2w(&1
import org.apache.commons.logging.Log; _-a|VTM
import org.apache.commons.logging.LogFactory; ,nE&MeJ
import org.flyware.util.page.Page; :0Te4UE;P7
i-13~Dk
import com.adt.bo.Result; Va9q`XbyO
import com.adt.service.UserService; X ]s"5ju|t
import com.opensymphony.xwork.Action; g,?\~8-c
1i,4".h?M
/** EzP#Mnz^
* @author Joa %]jQ48^R
*/ kMS5h~D[
publicclass ListUser implementsAction{ syFI$rf
_
X%J%A-k]
privatestaticfinal Log logger = LogFactory.getLog 3}4#I_<$F@
t,Q'S`eTU
(ListUser.class); Jk*QcEE=
C={mi#G[/
private UserService userService; 1~EO+
:0dfB&7
private Page page; u%aFb*
|uQ[W17^N
privateList users; >ZDC . ~
51/sTx<Z}
/* w{P6i<J
* (non-Javadoc) kknhthJ
* 8_awMVAy
* @see com.opensymphony.xwork.Action#execute() "i''Ui\H
*/ `t9.xB#Z
publicString execute()throwsException{ th Q J(w
Result result = userService.listUser(page); d"l}Ny)C
page = result.getPage(); iE+6UK
users = result.getContent(); %(NN*o9"q
return SUCCESS; V
Qh/
} D?J#u;h~f
k) 3s?
/** *s36OF!
* @return Returns the page. 500>
CBL0O
*/ #}j]XWy
public Page getPage(){ EFv4=OWB
return page; @|]G0&gn&?
} 7A[Ogro
F%y{%
C7l
/** #\0TxG5'QA
* @return Returns the users. -UTV:^
*/ 1zR/HT
publicList getUsers(){
h/{8bC@bi
return users; "bi !=
} K~$ 35c3M
`L;OY 4
/** pbFYiu+
* @param page KDX$.$#
* The page to set. -2z,cj&E{
*/ {Bc#?n
publicvoid setPage(Page page){ !b'IfDp[-!
this.page = page; 4"z;CGE7
} K^8@'#S
s?5d
/** >Rr!rtc'x
* @param users t+jIHo
* The users to set. we
}#Ru*
*/ .byc;9M%
publicvoid setUsers(List users){ 7
s7}?l9
this.users = users; |iAEDZn
} )4Bwt`VX
&Q<EfB
/** \I:UC
%
* @param userService eS*
*L3
* The userService to set. oy`3r5g
*/ 3g^IXm:K$
publicvoid setUserService(UserService userService){ QZ#3Bn%B5
this.userService = userService; L,O>6~9:^1
} #&}%70R)
} *m iONc
m9%yR"g9
4(m/D>6:
zI1(F67d`
`CPZPp,l6`
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, gv`%Z8u(
)~1.<((<
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 #W_i{bdO
3O #~dFnp
么只需要: Tw?Pp8'
java代码: " vv$%^
11PLH0
3S;>ki4(0
<?xml version="1.0"?> YCtIeq%
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork c`rfKr&z
`'dX/d
1.0//EN" "http://www.opensymphony.com/xwork/xwork- q]2}UuM|U
"(9=h@@Y"
1.0.dtd"> ~vO'p
r!"CH5dT
<xwork> jI@bTS o
E|KLK4]
<package name="user" extends="webwork- `HE>%=]b
@SX%?
mk8G
interceptors"> s?4%<jz
*?EjYI
<!-- The default interceptor stack name AT2NC6{M
B^E2UNRA
--> l:>qR/|m
<default-interceptor-ref ^(E"3 c
,Y78Q
name="myDefaultWebStack"/> jM|YW*zNZ
FCS5@l,'<
<action name="listUser" dVY(V&p
#n6FQ$l8m
class="com.adt.action.user.ListUser"> f(w#LuW<
<param F[Guy7?O
.j'@K+<45
name="page.everyPage">10</param> =R"Eb1
<result i-K"9z|)
mjkw&2
name="success">/user/user_list.jsp</result> 6Zl.Lh
</action> i9f7=-[U_
ZC9.R$}Kl
</package> *Bb|N--jI
V'f&JQA
</xwork> @8 oDy$j
K%aPl~e
hPEp0("
]%WD} 4e
qCxD{-9x{
8VAYIxRv
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 B~'VDOG$Z
Cnc\sMDJ\B
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 :!Y?j{sGU
O[5_9W
4
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 T?p`Y| gl
a@V/sh
\h'E5LO
:<WQ;q
J4*:.8Ki
我写的一个用于分页的类,用了泛型了,hoho Ndug9j\2
6iV"Tl{z-
java代码: s&QBFyKtJ
3Q!J9t5dc
YKX>@)Dxv
package com.intokr.util; Ql6ai
skC|io-Zv
import java.util.List; 8y4D9_{
C^\*|=*\
/** sP3.s_U^
* 用于分页的类<br> yV+ E;
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 8t*%q+Z
* 'Kso@St`o
* @version 0.01 L@k;L
* @author cheng 0Z);.l^
*/ "<jEI /
public class Paginator<E> { G=bP<XF
privateint count = 0; // 总记录数
;~gd<KK
privateint p = 1; // 页编号 :?:j$
=nWN
privateint num = 20; // 每页的记录数 1J{z}yPHc
privateList<E> results = null; // 结果 sG1]A:_<C
mP$G9R
/** T
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* 结果总数 c]>&6-;rf
*/ VgZaDd;
publicint getCount(){ (P>eWw\0
return count; FskJyB[
} @aV~.!!
>K|G LP
publicvoid setCount(int count){ ,<P[CUD&&
this.count = count; q[|`&6B
} +S5_J&~
_9-D3_P[3
/** !{ESeBSCG
* 本结果所在的页码,从1开始 ?'/5%f`
* ATmqq)\s
* @return Returns the pageNo. C8W`Oly:]
*/ })0 7u
publicint getP(){ j.'"CU
return p; {|J2clL
} R5;eR(24G
jme5'FR
/** -^jLU
FC
* if(p<=0) p=1 h. (;GJO
* vB YT)S
* @param p |^k1hX2?W
*/ F%+rOT<5
publicvoid setP(int p){ pn%|;
if(p <= 0) :6k DUFj}
p = 1; oJJk
this.p = p; 7CL@iL Tq
} .yfqS|(
'/Cz{<,
/** 1gy}E=noP
* 每页记录数量 $0S" Lh{
*/ O9=H
[b
publicint getNum(){ 9"lW"lG!
return num; s>``-
]3
} a={qA4N
Cbg#Yz~/
/** -zLI!F 0
* if(num<1) num=1 P5xmLefng
*/ $F()`L{Tj
publicvoid setNum(int num){ hGo|2@sc
if(num < 1) ZUJOBjb`
K
num = 1; *^+xcG
this.num = num; <IDzv'
} {BCjVmY
Y4qyy\}
/** j4SGA#;v
* 获得总页数 })SdaZ
*/ u\geD
publicint getPageNum(){ ]bE?n.NwZ
return(count - 1) / num + 1; "3 oU
(RA
} jh&vq=PH
RZh)0S>J
/** >@Vr'kg+V
* 获得本页的开始编号,为 (p-1)*num+1 9Zsb1 M!n>
*/ _O,ZeES
publicint getStart(){ +*{5ORq=
return(p - 1) * num + 1; vGHYB1=~
} dTQvz9 C
\\Tp40m+
/** 9:w,@Phe
* @return Returns the results. =?Md&%j
*/ E(LE*J
publicList<E> getResults(){ Byj~\QMD|
return results; YY~=h5$
} rg/vxTl
~RAH -]
public void setResults(List<E> results){ Fh$&puF2
this.results = results; 8vW`E_n
} k\%v;3nBK
a`iAA1HJ
public String toString(){ aBi:S3 qk
StringBuilder buff = new StringBuilder 'k Z1&_{
=T}uQ$X
(); t3g!5
buff.append("{"); qDd/wR,44
buff.append("count:").append(count); wT yM9wz&
buff.append(",p:").append(p); P$Ru NF
buff.append(",nump:").append(num); d( g_y m*
buff.append(",results:").append A'(F%0NF6
ScoHtX3
(results); %pQ o%<d
buff.append("}"); r/L]uSN
return buff.toString(); !PIdw~YC
} Lta\AN!c
YH9]T,
} Pv.@Y30
5K~6`
3[Iw%% q