Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 vR-rCve$P
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 #Ubzh`v
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 1k3wBc5<
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 TV0(uMZ0+'
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。 [:TOU^
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分页支持类: ``$At ,m
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java代码: =H3 JRRS
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package com.javaeye.common.util; 2*F["E
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import java.util.List; x]XhWScr'
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publicclass PaginationSupport { &ZClv"6
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publicfinalstaticint PAGESIZE = 30; >}43MxU?
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privateint pageSize = PAGESIZE; \y"!`.E7\d
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privateList items; /`?i&\C3r
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privateint totalCount; w*u HB;?
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privateint[] indexes = newint[0]; N9Y,%lQ|B8
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privateint startIndex = 0; Dwe_ytjpc
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public PaginationSupport(List items, int o[!]xmj
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totalCount){ _t'Kj\
setPageSize(PAGESIZE); #Kn=Q
setTotalCount(totalCount); `6?r.;wj
setItems(items); >-c ;
setStartIndex(0); v|<Dc8i+
} \[%[`m
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public PaginationSupport(List items, int QjVP]C}p
@;"HslU\Q
totalCount, int startIndex){ O}*[@uv/
setPageSize(PAGESIZE); xT#j-T
setTotalCount(totalCount); %j^[%&pT
setItems(items); =Bu d!
setStartIndex(startIndex); .3Jggp
} wk<QYLEk
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public PaginationSupport(List items, int (S&X??jfB5
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totalCount, int pageSize, int startIndex){ ]}<wS]1
setPageSize(pageSize); ?tQUZO
setTotalCount(totalCount); /Uz2.Ua=
setItems(items); S/"-x{Gc2v
setStartIndex(startIndex); ,3qi]fFLMe
} 7ZI!$J|
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publicList getItems(){ EXK~Zf|&Z
return items; 1X.5cl?V
} &D\~-fOGb
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publicvoid setItems(List items){ =.#*MYB.l
this.items = items; 9(dbou
} .-k\Q}D
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publicint getPageSize(){ LZqx6~]O
return pageSize; GE\@mu *pO
} 2v0lWO~c7z
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publicvoid setPageSize(int pageSize){ BXiuVx
this.pageSize = pageSize; JVD#wwic
} uZ&,tH/
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publicint getTotalCount(){ 6!
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return totalCount; _S7GkpoK
} ~Yv"=
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publicvoid setTotalCount(int totalCount){ <VS\z(K
if(totalCount > 0){ U{"&Jj
this.totalCount = totalCount; /lC n^E6-
int count = totalCount / ?{mFQ
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pageSize; %u-l6<w#R
if(totalCount % pageSize > 0) m
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count++; w&8gA[y*u
indexes = newint[count]; v[T5D:
for(int i = 0; i < count; i++){ ~M6Q8Y9
indexes = pageSize * ~Y<x-)R
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R
i; {0WLY@7 2?
} L5Rj;qhi
}else{ j)?I]j/
this.totalCount = 0; iqig~fjK~
} U{gJn#e/.
} mWZoo/xtT
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publicint[] getIndexes(){ V
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return indexes; RcitW;{|Kg
} M$d DExd~
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publicvoid setIndexes(int[] indexes){ /m%i"kki
this.indexes = indexes; *IJctYJaX
} <\|f;7/
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publicint getStartIndex(){ ,~w)~fMb8
return startIndex; x3xBl_t
} s
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publicvoid setStartIndex(int startIndex){ ymT&[+V
if(totalCount <= 0) DJr{;t$7~
this.startIndex = 0; LGGC=;{}
elseif(startIndex >= totalCount) !U>711$
this.startIndex = indexes @5K/z<p%
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[indexes.length - 1]; id8a#&t]
elseif(startIndex < 0) nyD(G=Q5
this.startIndex = 0; j
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else{ I:Wrwd
this.startIndex = indexes NdZv*
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[startIndex / pageSize]; @jAuSBy
} @x3x/gU
} J)D/w[w
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publicint getNextIndex(){ WBLfxr
int nextIndex = getStartIndex() + D|}
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pageSize; S-Mn
if(nextIndex >= totalCount) kaQn'5
return getStartIndex(); m!L&_Z|j
else 8*V^DM3n-
return nextIndex; Jf{6'Ub
} }A;J-7g6
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publicint getPreviousIndex(){ Xs$k6C3
int previousIndex = getStartIndex() - \2~Cn c*O
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pageSize; d#cw`h<c~
if(previousIndex < 0) a^t#kdT
return0; 2uu"0Rm%
else %:yJ/&-Q,Z
return previousIndex; NitWIj[U;
} :KGUO{_u
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} uA dgR
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抽象业务类 CKeT%3
java代码: '+LC.l M
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/** eS{lr4-]
* Created on 2005-7-12 E8j>Toz
*/ ohklLZoZ
package com.javaeye.common.business; me"}1REa
//S/pCqED
import java.io.Serializable; NPF"_[RoeV
import java.util.List; BWV)>
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import org.hibernate.Criteria; i;>Yx#
import org.hibernate.HibernateException; 8`l bKV
import org.hibernate.Session; U0G(
import org.hibernate.criterion.DetachedCriteria; (+lwt
import org.hibernate.criterion.Projections; E-\Wo3
import E9JxntX
b7 %Z~
org.springframework.orm.hibernate3.HibernateCallback; {3cT\u
import yU]NgG=z:-
b:VCr ^vp
org.springframework.orm.hibernate3.support.HibernateDaoS UPQ?vh2F2
Y@N-q
upport; sw
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jz ;N&62|
import com.javaeye.common.util.PaginationSupport; HE#IJB6BS?
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{
public abstract class AbstractManager extends NN\>(
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HibernateDaoSupport { tGv5pe*r
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privateboolean cacheQueries = false; .&fG_(6|
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privateString queryCacheRegion; 5'=\$Ob
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publicvoid setCacheQueries(boolean %X)w$}WH
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cacheQueries){ 91'i7&~xdG
this.cacheQueries = cacheQueries; KG7 ~)g
} %i[G6+-
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publicvoid setQueryCacheRegion(String }Fs;sfH
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queryCacheRegion){ lr[U6CJY
this.queryCacheRegion = 2H+!78
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queryCacheRegion; !0i6:2nw
} i [,9hp
} o^VEJc`O
publicvoid save(finalObject entity){ _D<=Yo
getHibernateTemplate().save(entity); 4h% G %>j
} TKJs'%Q7F6
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publicvoid persist(finalObject entity){ !C ]5_
getHibernateTemplate().save(entity); IkW8$>
} I|&<!{Rq
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publicvoid update(finalObject entity){ uW4)DT9[5
getHibernateTemplate().update(entity); ,i0Dw"/u
} NL`}rj
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publicvoid delete(finalObject entity){ E<6Fjy
getHibernateTemplate().delete(entity); i" 0]L5=P
} !' ;1;k);
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publicObject load(finalClass entity, FO[x
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finalSerializable id){ EyU 5r$G
return getHibernateTemplate().load rBY)rUDd4
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(entity, id); K,B qVu
} i{T mn
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publicObject get(finalClass entity, l=+hs
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finalSerializable id){ 7ns n8WN[
return getHibernateTemplate().get ldFK3+V
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(entity, id); pf&H !-M
} w~+C.4=7
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publicList findAll(finalClass entity){ 47<fg&T
return getHibernateTemplate().find("from R
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" + entity.getName()); 0Ncx':]5
} ^~dBO%M^
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publicList findByNamedQuery(finalString
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namedQuery){ ohLM9mc9
return getHibernateTemplate ,#/%Fn%T
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().findByNamedQuery(namedQuery); >oD,wSYV~
} c\P,ct
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publicList findByNamedQuery(finalString query, '.{tE*
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finalObject parameter){ v,}Mn7:
return getHibernateTemplate JCe%;U
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().findByNamedQuery(query, parameter); HGiO}|q:
}
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publicList findByNamedQuery(finalString query, o54/r#~fi
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finalObject[] parameters){ Fy6(N{hql
return getHibernateTemplate -e2f8PV?3
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().findByNamedQuery(query, parameters); e9\eh? bPU
} l.>3gjr
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publicList find(finalString query){ vz~`M9^
return getHibernateTemplate().find 6x*$/1'M3;
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(query); ;:WM^S
} Hoj'zY
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publicList find(finalString query, finalObject /s~(? =qYH
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parameter){ ._X|Ye9/
return getHibernateTemplate().find ?S8_x]E
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(query, parameter); {9c_T!c
} O)FkpZc@9c
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public PaginationSupport findPageByCriteria F!RzF7h1
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(final DetachedCriteria detachedCriteria){ ;5dA
return findPageByCriteria bxc!x>)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }VU7wMk
} &Hj1jM'
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public PaginationSupport findPageByCriteria \D5_g8m:
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(final DetachedCriteria detachedCriteria, finalint n/ CP2A
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startIndex){ [QZ8M@Gty#
return findPageByCriteria /EvnwYQy
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(detachedCriteria, PaginationSupport.PAGESIZE, p|`[8uY?
)b=m|A GX
startIndex); XS_Ib\-50
} }C'h<%[P
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public PaginationSupport findPageByCriteria Ly_.%f
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(final DetachedCriteria detachedCriteria, finalint 3?x}48
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pageSize, Z,QSbw@,7
finalint startIndex){ %;ZDw@_<
return(PaginationSupport) gyT3[*eh
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getHibernateTemplate().execute(new HibernateCallback(){ 1i=p5,|
publicObject doInHibernate 4yDWVd;
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(Session session)throws HibernateException { 8(@Y@`/
Criteria criteria = IAFj_VWC0
j"4]iI+ {"
detachedCriteria.getExecutableCriteria(session); +'`I]K>
int totalCount = Yw6d-5=:
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((Integer) criteria.setProjection(Projections.rowCount Egm-PoPe
X B[C&3I
()).uniqueResult()).intValue(); Fu*Qci1Z
criteria.setProjection E/Adi^
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(null); oFDJwOJ'Bj
List items = !4"<:tSO
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criteria.setFirstResult(startIndex).setMaxResults |Qz"Z<sNYw
~|R/w%*C
(pageSize).list(); BnPL>11Y
PaginationSupport ps = qG8-UOUDt
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new PaginationSupport(items, totalCount, pageSize, FV>xAU$
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startIndex); 'Im&&uSkr
return ps; Epm%/ {sHV
} @D2KDV3'
}, true); )#0Llx!
} wpepi8w,
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public List findAllByCriteria(final <xaB$}R
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DetachedCriteria detachedCriteria){ Q^|aix~ K
return(List) getHibernateTemplate G1S:hw%rp
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().execute(new HibernateCallback(){ pWN5 >HV
publicObject doInHibernate
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(Session session)throws HibernateException { wg{Y6XyH
Criteria criteria = Mb\[` 4z
/>[~2d
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detachedCriteria.getExecutableCriteria(session); BDc "0XH
return criteria.list(); c
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} A,f%0
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}, true); 0qk.NPMB0
} <^YZ#3~1T
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public int getCountByCriteria(final L~} 2&w
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DetachedCriteria detachedCriteria){ *h Bo,
Integer count = (Integer) d
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getHibernateTemplate().execute(new HibernateCallback(){ 5:x .<
publicObject doInHibernate O\[Td
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(Session session)throws HibernateException { /u N3"m5i
Criteria criteria = QAK.Qk?Qu
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detachedCriteria.getExecutableCriteria(session); SPY4l*kX
return f')3~)"
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criteria.setProjection(Projections.rowCount liG3
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()).uniqueResult(); K)n0?Q_>
} & wG3RR|
}, true); -Drm4sTpDb
return count.intValue(); }dSxrT
} J"O#w BM9
} j,CMcP7A -
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用户在web层构造查询条件detachedCriteria,和可选的 {r?qI
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 "yV)&4)
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PaginationSupport的实例ps。 X>6VucH{\
9,;+B8-A
ps.getItems()得到已分页好的结果集 R@H}n3,
ps.getIndexes()得到分页索引的数组 BlvNBB1^
ps.getTotalCount()得到总结果数 .`Ts'0vVy
ps.getStartIndex()当前分页索引 h8uDs|O9n
ps.getNextIndex()下一页索引 u:7=Yy
:
ps.getPreviousIndex()上一页索引 _ Oe|ZQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Oz1ou[8k
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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 D7Nz3.j
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一下代码重构了。 pd{;`EW|
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我把原本我的做法也提供出来供大家讨论吧: k^PqB+P!
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首先,为了实现分页查询,我封装了一个Page类: Y)L\*+
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java代码: 5bzYTK&-
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/*Created on 2005-4-14*/ 4';]fmf@[i
package org.flyware.util.page; >MIp r
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/** <#9zc'ED:
* @author Joa /@bLc1"
* ~Zd n#z\
*/ r,4V SyZF\
publicclass Page { 9/k?Lv
vAE?^*F
/** imply if the page has previous page */ 5B<G;if,
privateboolean hasPrePage; q[3b i!Q
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/** imply if the page has next page */ r4c3t,L*$I
privateboolean hasNextPage; Gr;~P*
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/** the number of every page */ ~;;_POm
privateint everyPage; O:a$ U:
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/** the total page number */ Ye}y_W
privateint totalPage; n~d`PGs?f
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/** the number of current page */ | We @p
privateint currentPage; 5W!E.fz*T
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/** the begin index of the records by the current Y4Z?`TL
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query */ vN7ihe[C
privateint beginIndex; {fMrx1
7,e=|%7.
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/** The default constructor */ V_(?mC
public Page(){ }#
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} R^F99L
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/** construct the page by everyPage fXw%2wg
* @param everyPage +WwQ!vWWd
* */ -c=IO(B/
public Page(int everyPage){ T[XI
this.everyPage = everyPage; 5.|rzk>
} o\Hg2^YY>
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/** The whole constructor */ /:e|B;P`k
public Page(boolean hasPrePage, boolean hasNextPage, .#h]_%
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int everyPage, int totalPage, 'EREut,>'
int currentPage, int beginIndex){ h3p 3~xq
this.hasPrePage = hasPrePage; "eQ9 6^'J
this.hasNextPage = hasNextPage; V_}`2.Pg
this.everyPage = everyPage; 2.&v{gq
this.totalPage = totalPage; l:HO|Mq
this.currentPage = currentPage; ^B& Z
this.beginIndex = beginIndex; F;ONo.v;
} HXdPKS4q
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/** 8XJ%Yuu
* @return @;<w"j`r
* Returns the beginIndex. 3 XfXMVm
*/ }C#YR(]
publicint getBeginIndex(){ 6w}:w?=6
return beginIndex; :M3l#`4Q
} O:7y-r0i
6g$04C3tHi
/** CaBTqo
* @param beginIndex EmY4>lr
* The beginIndex to set. O~,^x$ve
*/ X\%],"9%
publicvoid setBeginIndex(int beginIndex){ {b<8Z*4W
this.beginIndex = beginIndex; 5[gkGKkf_
} dIO\ lL
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/** xJ&StN/'
* @return V7[qf "
* Returns the currentPage. (Z,,H1L
*/ F'j:\F6C;
publicint getCurrentPage(){ )edM@beY_
return currentPage; =_yOX=g|
} N%B#f\N
8:&@MZQ&!
/** TVFGonVY
* @param currentPage %okEN!=
* The currentPage to set. sa#"@j)
*/ *Nt6 Ufq6
publicvoid setCurrentPage(int currentPage){ &6\rKOsn
this.currentPage = currentPage; fRa1m?%s
} p[uwG31IL`
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/** +u=xBhZ
* @return ,OasT!Sr
* Returns the everyPage. sG VC+!E
*/ e8lF$[i
publicint getEveryPage(){ Q49|,ou[H
return everyPage; [#Yyw8V#<
} vl*RRoJ
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/** 8Peqm?{5Y5
* @param everyPage bm+ Mr
* The everyPage to set. DSjo%Brd-
*/ hsE!3[[
publicvoid setEveryPage(int everyPage){ 1QN]9R0`#7
this.everyPage = everyPage; W.67, 0m$
} ^2??]R&Q
gR( c;
/** KcU,RTE
* @return =;{S>P!I(t
* Returns the hasNextPage. cKfYkJ)A'
*/ m|7g{vHVV
publicboolean getHasNextPage(){ NFSPw`f
return hasNextPage; AjlG_F
} V+Tj[:ok
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/** ~*[}O)7#
* @param hasNextPage =[k9{cVW
* The hasNextPage to set. #YNb&K
n
*/ -Qgfo|po
publicvoid setHasNextPage(boolean hasNextPage){ cu"%>>,,
this.hasNextPage = hasNextPage; m:41zoV
} PLY7qMw
S77Gc:[;8
/** *m"mt
* @return 4YCGh
* Returns the hasPrePage. ?eO|s5r
*/ 8r|LFuI
publicboolean getHasPrePage(){ <^~F~]wnH
return hasPrePage; 5Ci}w|c/>
} @E)XT\;3
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/** zR
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* @param hasPrePage 7RLh#D|
* The hasPrePage to set. ]S[r$<r$
*/ W#wM PsB
publicvoid setHasPrePage(boolean hasPrePage){ CeJ|z{F\
this.hasPrePage = hasPrePage; hB.dqv]^
} s=nds"J
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/** #X8[g _d/
* @return Returns the totalPage. TXa XJIp
* 4|e#b(!
*/ Ov|j{}=L=9
publicint getTotalPage(){ b?^n'0
return totalPage; w#1dO~
} t}tKm
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/** Mm;)O'XDE
* @param totalPage 4(&'V+o
* The totalPage to set. d;^?6V
*/ g3Q #B7A
publicvoid setTotalPage(int totalPage){ yS43>UK_W+
this.totalPage = totalPage; b?$09,{0
} 8j$q%g
6vA5L_
} yR!>80$j
; M(}fV]
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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 }:mI6zsNj
%FU[j^
个PageUtil,负责对Page对象进行构造: ?MYD}`Cv
java代码: la4,Z
HA%ye"(y8
o7+/v70D
/*Created on 2005-4-14*/ >
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package org.flyware.util.page; i/~J0qQ
P Cf|^X#B
import org.apache.commons.logging.Log; wl%1B64
import org.apache.commons.logging.LogFactory; LJy'wl
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/** JK(&E{80
* @author Joa $VA4% 9
* 6S<$7=$=
*/ rYJ))@
publicclass PageUtil { "v1(f| a
]G B},
privatestaticfinal Log logger = LogFactory.getLog AE711l-
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(PageUtil.class); 3$8}%?i
="DgrH
/** ttnXEF
* Use the origin page to create a new page 3(:mRb}
* @param page ~30Wb9eL
* @param totalRecords WFd2_oAT
* @return iV5I
*/ /v{[Z&z
publicstatic Page createPage(Page page, int *eP4dGe&
o zYI/b^
totalRecords){ Pb,^UFa=
return createPage(page.getEveryPage(), o,yvi
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page.getCurrentPage(), totalRecords); FQFENq''B
} ej;taKzj
pJz8e&wyLM
/** {yHfE,
* the basic page utils not including exception l8-jFeeMd
k)p y\
handler `<zb
* @param everyPage Xoy 1Gi?
* @param currentPage .6NSt
* @param totalRecords hYn'uL^~[
* @return page )^N8L<
*/ VK;x6*Y
publicstatic Page createPage(int everyPage, int 0UJ`<Bfd
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currentPage, int totalRecords){ 3ms/v:\
everyPage = getEveryPage(everyPage); F9\Ot^~
currentPage = getCurrentPage(currentPage); GZEonCk[&
int beginIndex = getBeginIndex(everyPage, (J&Xo.<Z-
mM*yv
currentPage); lrhAO"/1
int totalPage = getTotalPage(everyPage, k+[KD >;1
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totalRecords); gKN_~{{OD
boolean hasNextPage = hasNextPage(currentPage, \bic.0-
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totalPage); \`&pk-uW
boolean hasPrePage = hasPrePage(currentPage); P(epG?Qg
_}@n_E
returnnew Page(hasPrePage, hasNextPage, ?(q*U!=
everyPage, totalPage, Vb^s 'k
currentPage, 4i/q^;`
0>=)
beginIndex); #2jn4>
} $
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privatestaticint getEveryPage(int everyPage){ RYl3txw
return everyPage == 0 ? 10 : everyPage; _[i=TqVmf
} !rg0U<bO!
@>2rz
privatestaticint getCurrentPage(int currentPage){ I#t9aR+&
return currentPage == 0 ? 1 : currentPage; H?j-=Zka
} 4AOS}@~W
U;{,lS2l
privatestaticint getBeginIndex(int everyPage, int MQ(/l_=zQ
W 8$=a
currentPage){ mN{ajf)@
return(currentPage - 1) * everyPage; B"m:<@ "
} Kxc$wN<
O2]r]9sh*
privatestaticint getTotalPage(int everyPage, int =6<w'>
;b?+:L
totalRecords){ 1qj%a%R
int totalPage = 0; >zg8xA1zL
&]6K]sWJK{
if(totalRecords % everyPage == 0) CY3 \:D0I
totalPage = totalRecords / everyPage; 8[1DO1*P
else ^la i!uZVa
totalPage = totalRecords / everyPage + 1 ; LnTe_Q7_
90iW-"l+[
return totalPage; x;FO|fH
} mnQjX ?
2${,%8"0s
privatestaticboolean hasPrePage(int currentPage){ m0\"C-Bk
return currentPage == 1 ? false : true; n5k^v$'
} }gi1?a59
.;Utkf'I
privatestaticboolean hasNextPage(int currentPage, 4zqE?$HM'
\kV7NA
int totalPage){ uP{+?#a_-\
return currentPage == totalPage || totalPage == P}+|`>L
39T&c85
0 ? false : true; 3TiXYH
} 7
Mki?EG
O&gwr
9[p}.9/
} ~I\r1Wj;
O3C)N
I\i
0Dm`Ek3A7x
!
jX+ox
xeYySM=
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。 2gL[\/s
/ik)4]>
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 jO&f*rxN
E8iadf49
做法如下: %<=vbL9
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 9(^X2L&Z
_N,KHxsG8B
的信息,和一个结果集List: m{lRFKx>s
java代码: h"BhTx7E}
)1Ma~8Y%r
>b4YbLkI#
/*Created on 2005-6-13*/ $: 4mOl
package com.adt.bo; =>:% n
krr-ZiK
import java.util.List; mU?&\w=v$
3\p]esse
import org.flyware.util.page.Page; yToT7 X7F7
e1`)3-f
/** +%e%UF@
* @author Joa h2/dhp
*/ GwMUIevO_
publicclass Result { .}$`+h8WT
Y1yXB).AH8
private Page page; f^6&Fb>
g`)/ x\
private List content; (Y'UvZlM%P
^b"x|8
/** hHfe6P
|
* The default constructor 'TK$ndy;7}
*/ f
$.\o
public Result(){ =0s`4Y"+
super(); %qNj{<&
}
'{j\0
$LxG>db
/** l${Hgn+
* The constructor using fields ~51kiQW
* _cxm}*}\#
* @param page %;=IMMK
* @param content Imh2~rw;
*/ }"&n[/8~
public Result(Page page, List content){ =#.8$oa^
this.page = page; %)<oX9E
this.content = content; OUlxeo/
} I*+LJy;j
)I Y 5Y
/** XDP6T"h
* @return Returns the content. r|\5'ZMx
*/ HC9vc,Fp
publicList getContent(){ M]6w^\4j9
return content; c]%;^)
} k Z+ q
zH=/.31Q
/** -+
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* @return Returns the page. jlRl2 #"
*/ ,yHzo
public Page getPage(){ Qb6QXjN
Q
return page; (6ohrM>Q
} vk4C_8m
DJ1XNpm
/** b[{m>Fa+o#
* @param content j{Yt70Wv
* The content to set. YZ"+c&V"
*/ <?>I\
public void setContent(List content){ "%.|n|
this.content = content; SQdzEF
} z`86-Ov
X\b}jo^96
/** f"ZqA'KB#
* @param page zx\.2<K
* The page to set. ;uM34^
*/ ,-cpsN
publicvoid setPage(Page page){ u=d`j
this.page = page; vCy.CN$
} XJ
f+Eh
} 1V*8,YiC<
hb /8Q
.KT 7le<Zm
hV3,^#9o
'WKu0Yi^'
2. 编写业务逻辑接口,并实现它(UserManager, "B|nh d
mC*W2#1pF
UserManagerImpl) S F&M
(=w<
java代码: p<of<YU)
ESC
ql{^"8x
/*Created on 2005-7-15*/ =R8f)UQYx
package com.adt.service; (ZE%tbm2
$Q`yNEc
import net.sf.hibernate.HibernateException; 4 o3)*
6T^N!3p_
import org.flyware.util.page.Page; U7nsMD
BpQ;w,sefq
import com.adt.bo.Result; !7:EE,W~
]iz_w`I\
/** q=P
f^Xp
* @author Joa 652u Z};e
*/ [5]R?bQ0q{
publicinterface UserManager { 4&FNU)tt
2k.S[?)
public Result listUser(Page page)throws cOzg/~\1
*fxep08B
HibernateException; F`YFo)W
lEO?kn.:z
} S2koXg(
p&k0Rx0Q3
'P@=/
ucQezmie
G*)s%2c>h
java代码: zrLhQ3V#>
*)j@G:
(/T+Wpy?
/*Created on 2005-7-15*/ XoDJzrL#
package com.adt.service.impl; L/qZ ; {
,3w I~j=
import java.util.List; #rhVzN-?)W
2LCc
import net.sf.hibernate.HibernateException; Nbgp_:{
pd=7^"[};
import org.flyware.util.page.Page; N; rXl8
import org.flyware.util.page.PageUtil; b*lKT]D,
S9OxI$6Y
import com.adt.bo.Result; hVlyEsLg
import com.adt.dao.UserDAO; &E.OyqGZV
import com.adt.exception.ObjectNotFoundException; !d:tIu{)
import com.adt.service.UserManager; U3mXm?f
0^J*+
/** )vO_sIbnW
* @author Joa NJ
>I%u*
*/ tH-gaDj_
publicclass UserManagerImpl implements UserManager { @Djs[Cs<*
vg+r?4Q3
private UserDAO userDAO; '9^E8+=|
}R`8h&J
/** zXj>K3M
* @param userDAO The userDAO to set. dj?G.-
*/ V8-4>H}Cb/
publicvoid setUserDAO(UserDAO userDAO){ Wl,%&H2S<
this.userDAO = userDAO; I'x$,s
} Q<z)q<e
*
zd.
/* (non-Javadoc) a^@+%?X
* @see com.adt.service.UserManager#listUser r`?&m3IOP
b0y-H/d/}
(org.flyware.util.page.Page) I|$'Q$m~
*/ WEno+Z~=1'
public Result listUser(Page page)throws %0NL Rfp
B#J{ F
HibernateException, ObjectNotFoundException { $`E4m8fX
int totalRecords = userDAO.getUserCount(); V78Mq:7d
if(totalRecords == 0) x*:n4FZ7b
throw new ObjectNotFoundException P1dN32H
o
!?yxh/>lM
("userNotExist"); gs$3)t
page = PageUtil.createPage(page, totalRecords); _Mlhumt
List users = userDAO.getUserByPage(page); x2Ha&
returnnew Result(page, users); aZ8h[#]7
} FL59
RwUW;hU
} Vz%"9`r
S*;#'j)4+
>r~0SMQr
j6`6+W=S(
$B<~0'6}
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 CP}0Ri)
uRP
Ff77
询,接下来编写UserDAO的代码: O\%j56Bf
3. UserDAO 和 UserDAOImpl: AzZi{Q ?
java代码: pMOD\J:l,
N[>:@h
"_t4F4z
/*Created on 2005-7-15*/ _\p`4-.V
package com.adt.dao; /#29Y^Z)=
wtlB
import java.util.List; [70Y,,w
wbBE@RU>!
import org.flyware.util.page.Page; IT,"8s
QDP-E[
import net.sf.hibernate.HibernateException; SzRL}}I
2%bhW,?I
/** S<*' ;{5~
* @author Joa '=$TyiU
*/ MdLj,1_T
publicinterface UserDAO extends BaseDAO { R j-jAH
cnbo+U
publicList getUserByName(String name)throws HTw#U2A;+
`Rrr>vj
HibernateException; E`~i-kf
ma3Qi/
publicint getUserCount()throws HibernateException; q5!0\o:
R;%^j=Q
publicList getUserByPage(Page page)throws NOV.Bs{
yL
8:~b
&>
HibernateException; miPmpu!
se!g4XEWD
} YRXK@'[=
L+Eu
d
9wzwY[{
]Uu
aN8
b"^\)|*4;
java代码: Xp#~N_S$
/GyEV Cc
o94PI*.
/*Created on 2005-7-15*/ Ohc^d"[7
package com.adt.dao.impl; hRk,vB]
_<XgC\4O|
import java.util.List; k/U>N|5
B+|IZoR
import org.flyware.util.page.Page; 2f `&WUe
-W9gH
import net.sf.hibernate.HibernateException; 9g96 d-
import net.sf.hibernate.Query; m.!wsw
jBS'g{y-!
import com.adt.dao.UserDAO; Ny]lvgu9X
r-*l1([eW
/** Bf/|{@
* @author Joa gUspGsfr
*/ N_0pO<<cs
public class UserDAOImpl extends BaseDAOHibernateImpl @Zj&`/
HXyFj
implements UserDAO { Q@3B{
_g65pxt =Z
/* (non-Javadoc) &u("|O)w$
* @see com.adt.dao.UserDAO#getUserByName YKNb59k
H)\4=^
(java.lang.String) whw{dfE
*/ v3~FR,Kl
publicList getUserByName(String name)throws \PzN XQ$
NfOp=X?Y
HibernateException { RFB(d=o5S
String querySentence = "FROM user in class 9Kx<\)-GMD
*G\=i
A
com.adt.po.User WHERE user.name=:name"; >C:If0S4X
Query query = getSession().createQuery EPv%LX_j
b1H7
(querySentence); Nvhy3
query.setParameter("name", name); =88t*dH(,"
return query.list(); 3Mur*tj#
} ERp{gB2U?
(V8?,G >
/* (non-Javadoc) %TDXF_.[
* @see com.adt.dao.UserDAO#getUserCount() J,9%%S8/C
*/ ;|;iCaD a+
publicint getUserCount()throws HibernateException { 1b8c67j[
int count = 0; wz h.$?~
String querySentence = "SELECT count(*) FROM - {0g#G
4Mi~1iZj
user in class com.adt.po.User"; !M,h79NM
Query query = getSession().createQuery U[ bgu#P;
0_Lm#fE U
(querySentence); q1jN]H
count = ((Integer)query.iterate().next !8o\.uyi
2Sjt=LOc="
()).intValue();
">cqt>2 A
return count; V\"1wV~E
} &/iFnYVhy
>2u y
/* (non-Javadoc) lf6|.
* @see com.adt.dao.UserDAO#getUserByPage XO%~6Us^
loBtd%wY
(org.flyware.util.page.Page) TH YVT%v
*/ vkuc8 li
publicList getUserByPage(Page page)throws m!0N"AjA
ex!XB$X
HibernateException { Qne0kB5m
String querySentence = "FROM user in class IyOpju)?
IKo;9|2U
com.adt.po.User"; UDMyyVd
Query query = getSession().createQuery 4j{oaey
?|lI Xz
(querySentence); 6Etss!_
query.setFirstResult(page.getBeginIndex()) lJUy;yp_+
.setMaxResults(page.getEveryPage()); \1]rlzXGUT
return query.list(); W-ez[raY
} _Ds@lVY
>IBTBh_ka
} "9%qbMB
UP]1(S?
"1K:/n
#cO+ <1
=&N$Vqn
至此,一个完整的分页程序完成。前台的只需要调用 E0<)oQ0Xa>
"ee'2O
userManager.listUser(page)即可得到一个Page对象和结果集对象 zA,/@/'(
s%^o*LQ|9
的综合体,而传入的参数page对象则可以由前台传入,如果用 (![t_r0
Y<aO
webwork,甚至可以直接在配置文件中指定。 o)p[
C
gJK KR]4*
下面给出一个webwork调用示例: K?[)E3
java代码: %Lyz_2q A
1|]xo3j"'
dqxd3,Z
/*Created on 2005-6-17*/ [g`, AmR\!
package com.adt.action.user; 7=vYO|a/4
_[F@1NJ
import java.util.List; Qm; BUG]
7OE[RX8!f
import org.apache.commons.logging.Log; wA631kr
import org.apache.commons.logging.LogFactory; SOs,)
import org.flyware.util.page.Page; rd">JEK;;
rw]yKH
import com.adt.bo.Result; #)`\!)?
import com.adt.service.UserService; IkU|W3Vo
import com.opensymphony.xwork.Action; Dp`HeSKU^
$WR?
/** Wy.";/C
* @author Joa Je@k iE
*/ @701S(0'7
publicclass ListUser implementsAction{ {"jd_b&
gApz:K[l
privatestaticfinal Log logger = LogFactory.getLog _YLUS$Zw
!*_K.1'
(ListUser.class); sl^n6N
@mNJ=mEV
private UserService userService; 9x[ U$B
Z7KXWu+6`m
private Page page; .jargvAL*
{>h97}P
privateList users; B4^`Sw
c.0]1
/* F"[3c6yF
* (non-Javadoc) ABZ06S/
* hiN/S|JN8y
* @see com.opensymphony.xwork.Action#execute() 5
q65nF
*/ >C# kqxfg
publicString execute()throwsException{ cQn)^jx=
Result result = userService.listUser(page); [@|be.g
page = result.getPage(); A="fj
users = result.getContent(); Ye@t_,)x
return SUCCESS; n,sY\=vB
} `m, Ki69.
OX^3Q:Z=
/** s/h7G}Mu
* @return Returns the page. ul=7>";=|
*/ ;s}3e#$L
public Page getPage(){ 7k~Lttuk
return page; ]F+K|X9-
} sf)W~Lx5a
lQL:3U0DjU
/** gz4UV/qr/
* @return Returns the users. fv2=B)8$
*/ a:b^!H>#
publicList getUsers(){ M(2`2-/xh
return users; mW +tV1XjG
} .8(%4ejJ(
;UpJ=?W
/** Uouq>N
* @param page wS%zWdsz
* The page to set. 02pplDFsM
*/ hfv%,,e
publicvoid setPage(Page page){ VMF|iB
this.page = page; t%$@fjz
} 1a8$f5
5r7h=[N
/** $H;+}VQ
* @param users L=g_@b
* The users to set. ^/a*.cu
*/ m|1n
x
publicvoid setUsers(List users){ ?ZX!7^7
this.users = users; VDpxk$a
} RHI&j~
3\+N`!
/** l;0y-m1
* @param userService _Ex|f5+
* The userService to set. J*K<FFp3<
*/ Ow)R|/e/
publicvoid setUserService(UserService userService){ R&Ci/
this.userService = userService; .[(P
} T VeJ6
} v|&s4x?D
=<.F3lo\s
D:m#d.m
'HB~Dbq`V
/[?Jylj
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, 0H+c4IW
#8UseK
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 u]bz42]
LS6ry,D"7
么只需要: 8W,*eke?
java代码: d.cCbr:
C0<YH "
Nv3tt
<?xml version="1.0"?> *~;8N|4<
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 6#|qg*OS
>qpqQ;
bm
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 8Zw]f-5x\
;"@ :}_t
1.0.dtd"> Ay%:@j(E
wv^b_DR
<xwork> (Oq Hfv
+'%\Pr(
<package name="user" extends="webwork- afUTAP@
(Fqa][0
interceptors"> }#
Xi`<{
S_5?U2%D
<!-- The default interceptor stack name (yGQa5v
Hg whe=P
--> jb3.W
<default-interceptor-ref Spo+@G
L|J~9FM
name="myDefaultWebStack"/> F`srE6H
EneAX&SG
<action name="listUser" q,@+^aZ
@\PpA9ebg%
class="com.adt.action.user.ListUser">
qpTm
<param W_m!@T"@H
U`1l8'W}:#
name="page.everyPage">10</param> 4+Ti7p06&\
<result blp=Hk
BKZ v9
name="success">/user/user_list.jsp</result> H"D5e
</action> Azn:_4O
-|[~sj-p
</package> ?Pnx~m{%*
fYn{QS?
</xwork> QS;F+cmTh
B{PLIisc
:~33U)?{T
f`J|>Vk
g}r^Xzd;
PCZ]R
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 +6376$dC
@/(@/*+"
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 LzE/g)>
9[sG1eP!
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 5p
)IV>G
+V1}@6k
:
MWhwMj!:m
j{"[Ec
"Z~`e]>
我写的一个用于分页的类,用了泛型了,hoho Pw
xIz
o&,Y<$!:VH
java代码: /{R3@,D[]
{XHk6w
*-
|*E"G5WZM
package com.intokr.util; ~d>uXrb
lR}%)3_k
import java.util.List; h?A'H RyL~
T3rn+BxF 7
/** 6l[G1KkV
* 用于分页的类<br> @'HT;Q!\Vd
* 可以用于传递查询的结果也可以用于传送查询的参数<br> xE1rxPuq)d
* k(v"B@0
* @version 0.01 c _mq
* @author cheng iokPmV
*/ HtUG#sc&`{
public class Paginator<E> { gn`zy9PU
privateint count = 0; // 总记录数 ls]H6z*q
privateint p = 1; // 页编号 C$K+=jT
privateint num = 20; // 每页的记录数 G
*@@K
privateList<E> results = null; // 结果 B-dlm8gX
e`AUYli"
/** fkG##!
* 结果总数 4,zvFH*AH
*/ *:j-zrwu&
publicint getCount(){ L;Vq j]_
return count; L~
2q1
} <tW:LU(!
~v\hIm3=m
publicvoid setCount(int count){ #s{aulx
this.count = count; (Com,
} 1 KB7yG-#6
Z8fJ{uOIL
/** OM{Dq|
* 本结果所在的页码,从1开始 0T0/fg(o
* CpSK(2j
* @return Returns the pageNo. CrO`=\
*/ ]hKgA~;
publicint getP(){ 6}STp_x
return p; C d|W#.6
} %wtXo BJ
2/EK`S
/** u?Z
<n:
* if(p<=0) p=1 `I{ tZ$iD
* [9HYO
* @param p 117c,yM0
*/ \=Nm5:
publicvoid setP(int p){ &D)2KD"N
if(p <= 0) 0#
l#,Y6#I
p = 1; |i u2&p >
this.p = p; |=u96G~N
} 6+)x7g1PL
SXh?U,5u
/** u>m'FECXj
* 每页记录数量 Otxa<M+"
*/ >fg4x+0 %
publicint getNum(){ tO`?{?W7
return num; T*R{L
} sxk*$jO[]
:Dj#VN
/** 5pmQp}}R
* if(num<1) num=1 o~k;D{Snr
*/ "4RQ`.SR
publicvoid setNum(int num){ }>,CUz
if(num < 1) i3d y
num = 1; sNf
+ lga0
this.num = num; 4]IKh,jT
} k{1b20
EP(Eq
/** CdNih8uG
* 获得总页数 Pr2;Kp
*/ I5Q~T5Ar
publicint getPageNum(){ 5v+L';wx[T
return(count - 1) / num + 1; ?eVj8 $BQo
} %!yxC
~ttKI4
/** @C07k^j=U
* 获得本页的开始编号,为 (p-1)*num+1 ", QPb3
*/ j)BQMtt&U
publicint getStart(){ _<3r'Y,
return(p - 1) * num + 1; M_; w%FV
}
VmYBa(
Qi"'bWX@
/** j=\Mx6os
* @return Returns the results. ,$ mLL
*/ I^@.Awt
publicList<E> getResults(){ HGb.656r
return results; V>r j$Nc]
} 5)8.
LC76 Qi;|k
public void setResults(List<E> results){ ho_4fDv
this.results = results; smbUu/
} k0knPDbHv
t%:G|n Sz
public String toString(){ #.b^E3#+
StringBuilder buff = new StringBuilder *.xZfi_|
Stt* 1gT
(); MorW\7-}
buff.append("{"); I X?@~'
buff.append("count:").append(count); egbb1+tY
buff.append(",p:").append(p); OFQ{9
buff.append(",nump:").append(num); "!^c
buff.append(",results:").append 'cYQ?;
ze
?CoDx2
(results); tbY SK
buff.append("}"); (c<