Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 eV"%(<{
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 jzf~n~
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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 c';~bYZ
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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 yu6~:$%H
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分页支持类: 9i\}^ s2
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java代码: \udB4O
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package com.javaeye.common.util; JM;bNW8
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import java.util.List; !5d n7Wuj
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publicclass PaginationSupport { n@`3O'S
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publicfinalstaticint PAGESIZE = 30; `:lcN0n
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privateint pageSize = PAGESIZE; _ %mm
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privateList items; 2M+RA}dX
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privateint totalCount; L~ax`i1:"
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privateint[] indexes = newint[0]; MLr L"I"
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privateint startIndex = 0; +_:p8,
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public PaginationSupport(List items, int Y<;C>Rs
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totalCount){ s-*N_Dv
setPageSize(PAGESIZE); 8GxT!
setTotalCount(totalCount); tgBA(2/Co
setItems(items); "|i1 AR:I
setStartIndex(0); fp||<B
} PE7V1U#$o,
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public PaginationSupport(List items, int o,k#ft<
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totalCount, int startIndex){ h`fZ8|yw
setPageSize(PAGESIZE); `*CoVx~fk
setTotalCount(totalCount); }c/#WA|b
setItems(items); W{IP}mM
setStartIndex(startIndex); -6 v?iiZr
} W9cvxsox
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public PaginationSupport(List items, int ZHen:
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totalCount, int pageSize, int startIndex){ CWs;1`aP
setPageSize(pageSize); Nt+UL/1]
setTotalCount(totalCount); ,S(_YS^m
setItems(items); J'cE@(US
setStartIndex(startIndex); a
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} q&ed4{H<
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publicList getItems(){ dd=5`Bo9Yh
return items; >&<D.lx
} \mN?5QCcE
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publicvoid setItems(List items){ ?Wt_Obl
this.items = items; pfim*\'
} TuMZHB7h;
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publicint getPageSize(){ W6B o\UK
return pageSize; C~iFFh6:
} jaThS!>v
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publicvoid setPageSize(int pageSize){ RAyR&p
this.pageSize = pageSize; 1?+)T%"
} (K"t</]
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publicint getTotalCount(){ s|!b: Ms`
return totalCount; BJ/#V)
} \No22Je6d
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publicvoid setTotalCount(int totalCount){ _Q;M$.[zyR
if(totalCount > 0){ ,TO&KO1;&
this.totalCount = totalCount; = &aD!nTx
int count = totalCount / ?yz}
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pageSize; X 'bp?m
if(totalCount % pageSize > 0) sXC]{]
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count++; H+2J.&Ch
indexes = newint[count]; $j}sxxTT
for(int i = 0; i < count; i++){ .J\U|r
indexes = pageSize * H"?-&>V-
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} "/XS3sv"s
}else{ R}+/jh2O|
this.totalCount = 0; /0YNB)
} TbU9
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} 8UL:C?eY
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publicint[] getIndexes(){ A8eli=W
return indexes; |-aj$u%~
} \&qVr1|
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publicvoid setIndexes(int[] indexes){ TAC\2*bWje
this.indexes = indexes; ~ pdf'
} /~tfP
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publicint getStartIndex(){ x?<5=,
return startIndex; IKr7"`
} ta 6WZu
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publicvoid setStartIndex(int startIndex){ Q#r 0DWo\
if(totalCount <= 0) Yh%wf3
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this.startIndex = 0; t@ JPnA7~
elseif(startIndex >= totalCount) h'fD3Gr&
this.startIndex = indexes A0X0t
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[indexes.length - 1]; n*6s]iG
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elseif(startIndex < 0) y?@Y\ b
this.startIndex = 0; I~qiF%?d
else{ *nW9)T
this.startIndex = indexes NU(/Yit
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[startIndex / pageSize]; XP^6*}H.*
} HgBg,1
} ,"VQ0Z1
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publicint getNextIndex(){ @YB\PVhW
int nextIndex = getStartIndex() + pOYtN1uN|
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pageSize; ,<
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if(nextIndex >= totalCount) EDQJ>c
return getStartIndex(); |\(/dXXP
else ^Q,/C8qeb
return nextIndex; *vO'Z &
} L K~,
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publicint getPreviousIndex(){ LI<5;oE;
int previousIndex = getStartIndex() - .KsvRx
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pageSize; M<srJ8|'
if(previousIndex < 0) Madaxx
return0; WLl9>v^1
else _MEv*Q@o
return previousIndex; zNf5OItx
} EG.C2]Fi
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} .Cus t
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抽象业务类 K-u/q6ufK
java代码: k#) .E X
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/** z0[ZO1Fo(
* Created on 2005-7-12 |pR$' HO
*/ !S-U8KI|
package com.javaeye.common.business; <R>ZG"m {
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import java.io.Serializable; OF/)-}!
import java.util.List; 6S[D"Q94
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import org.hibernate.Criteria; eBIR*TZ):
import org.hibernate.HibernateException; n^02@Aw
import org.hibernate.Session; U.'@S8
import org.hibernate.criterion.DetachedCriteria; Y`?X Fy:
import org.hibernate.criterion.Projections; ]?`p_G3O
import J6ShIPc
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org.springframework.orm.hibernate3.HibernateCallback; k#*yhG,]'
import H;|:r[d!
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org.springframework.orm.hibernate3.support.HibernateDaoS H`lD@q'S
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upport; rI+w1';C1
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import com.javaeye.common.util.PaginationSupport; /+`<X%^U
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public abstract class AbstractManager extends GTe:k
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HibernateDaoSupport { :qTcxzV
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privateboolean cacheQueries = false; bXwoJ2
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privateString queryCacheRegion; xevP2pYG:
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publicvoid setCacheQueries(boolean :;;WK~*#
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cacheQueries){ EvQwGt1)P
this.cacheQueries = cacheQueries; {V%O4/
} Guw|00w,Q$
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publicvoid setQueryCacheRegion(String EQ63VF
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queryCacheRegion){ k +#l;<\2
this.queryCacheRegion = |EV\a[
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queryCacheRegion; O& %"F8B
} vF6*c
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publicvoid save(finalObject entity){ tb?F}MEe
getHibernateTemplate().save(entity); A:bPIXb
} R 4$Q3vcH
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publicvoid persist(finalObject entity){ m_!vIUOz
getHibernateTemplate().save(entity); TF0-?vBWh
} YG 5Z8@kH
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publicvoid update(finalObject entity){ G9n /S=R?
getHibernateTemplate().update(entity); jXY;V3l
} b?]ly(
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publicvoid delete(finalObject entity){ 5u|=;Hz*)
getHibernateTemplate().delete(entity); A?IZ(
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} Zp(=[n5
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publicObject load(finalClass entity, '`]n_$f'
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finalSerializable id){ |v$%V#Bo
return getHibernateTemplate().load _h1 HuL
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(entity, id); RJRq` T|m
} o\]:!#r{T
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publicObject get(finalClass entity, Dpdn%8+Z
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finalSerializable id){ fEj9R@u+h
return getHibernateTemplate().get t$H':l0
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(entity, id); OHHNWg_5
} P^8^1-b
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publicList findAll(finalClass entity){ Z(Eke
return getHibernateTemplate().find("from %Ui{=920
r*6"'W>c6
" + entity.getName()); Hz]4A S
} h"u<E\g
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publicList findByNamedQuery(finalString 2#AeN6\@
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namedQuery){ :F7k{~
return getHibernateTemplate &r'{(O8$N
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().findByNamedQuery(namedQuery); TsaW5ho<p
} a{]g+tGH
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publicList findByNamedQuery(finalString query, *.m{jgi1X
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finalObject parameter){ x?, ~TC4
return getHibernateTemplate 1mJbQ#5
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().findByNamedQuery(query, parameter); GA|/7[I}
} (O8,zqP9l
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publicList findByNamedQuery(finalString query, -6rf( ER
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finalObject[] parameters){ ta&Q4v&-
return getHibernateTemplate Md8(`@`o
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().findByNamedQuery(query, parameters); r0F_;
} YXF#c)#
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publicList find(finalString query){ `nT?6gy
return getHibernateTemplate().find )K{o<m~WAo
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(query); IWAj Mwo
} p{NPcT%&
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publicList find(finalString query, finalObject !xkj30O(G
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parameter){ n}19?K]g
return getHibernateTemplate().find 6 -]>]Hr-
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(query, parameter); x.I][(}
} 1'Nh jL
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public PaginationSupport findPageByCriteria Ay2b,q
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(final DetachedCriteria detachedCriteria){ F4Rr26M
return findPageByCriteria j*XjY[
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); M9gOoYf,~
} 9*' &5F=
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public PaginationSupport findPageByCriteria O47PkP8
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(final DetachedCriteria detachedCriteria, finalint vruD U#
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startIndex){ 2zhn`m
return findPageByCriteria 0}B?sNr
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(detachedCriteria, PaginationSupport.PAGESIZE, mKM,kY
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startIndex); CA/ -Gb
} OZ=Cp$
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public PaginationSupport findPageByCriteria $|k%@Q>
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(final DetachedCriteria detachedCriteria, finalint /N>} 4Ay
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pageSize, 0*/kGvw`i
finalint startIndex){ "v5ElYG
return(PaginationSupport) /
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getHibernateTemplate().execute(new HibernateCallback(){ h(nj,X+
publicObject doInHibernate n&$/Q$d&
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(Session session)throws HibernateException { b:1 L@8s;
Criteria criteria = L!,d"wuD
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detachedCriteria.getExecutableCriteria(session); ~cIl$b
int totalCount = `Ug tvo
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((Integer) criteria.setProjection(Projections.rowCount "TNVD"RLY
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()).uniqueResult()).intValue(); B)M&\:
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criteria.setProjection V#L'7">VP
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(null); b!^@PIX
List items = &qKigkLd
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criteria.setFirstResult(startIndex).setMaxResults ,5{$+
7\X$7
(pageSize).list(); f!x[ln<
PaginationSupport ps = VO_dA4C}z
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new PaginationSupport(items, totalCount, pageSize, O%&cE*eX
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startIndex); FshC )[w,
return ps; :y1 Bt+Fp
} DZk1ZLz
}, true); :IZ"D40m"
} nxfoWy
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public List findAllByCriteria(final y3JMbl[S0
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DetachedCriteria detachedCriteria){ KmmQ ,e%
return(List) getHibernateTemplate m*Cu-6&qd
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().execute(new HibernateCallback(){ Qnt5HSSt
publicObject doInHibernate TH:W#Ot
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(Session session)throws HibernateException {
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Criteria criteria = d:rGyA]
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detachedCriteria.getExecutableCriteria(session); IPtvuEju\
return criteria.list(); #]Y*0Wzpfn
} a
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}, true); >bIF>9T
} g)1X&>
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public int getCountByCriteria(final `]<`$71w
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DetachedCriteria detachedCriteria){ =J/ FJb
Integer count = (Integer) >2lwWXA
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getHibernateTemplate().execute(new HibernateCallback(){ ?fK1
publicObject doInHibernate ,H[SI0];
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(Session session)throws HibernateException { n >FY?
Criteria criteria = z9
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detachedCriteria.getExecutableCriteria(session); r\qz5G *6
return |5MbAqjzC
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criteria.setProjection(Projections.rowCount 4XJiIa?
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()).uniqueResult(); C5X(U:
} Vw~\H Gs/~
}, true); sWqM?2g
return count.intValue(); l,`!rF_
} 5v
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} VR0=SE
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用户在web层构造查询条件detachedCriteria,和可选的 Q8nId<\(
ELD!{bMT
startIndex,调用业务bean的相应findByCriteria方法,返回一个 ] d?x$>
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PaginationSupport的实例ps。 K=\O5#F?3
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ps.getItems()得到已分页好的结果集 AkBMwV
ps.getIndexes()得到分页索引的数组 E"PcrWB&
ps.getTotalCount()得到总结果数 i$^ZTb^
ps.getStartIndex()当前分页索引 q|(W-h+
ps.getNextIndex()下一页索引 mUP. rb6
ps.getPreviousIndex()上一页索引 \>Zvev!s
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3iX?~
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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 kxB.,'
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一下代码重构了。 pPro }@@
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我把原本我的做法也提供出来供大家讨论吧: 2N [=
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首先,为了实现分页查询,我封装了一个Page类: R9o- `Wz
java代码: 0 p uY"[c
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/*Created on 2005-4-14*/ K\?]$dK5
package org.flyware.util.page; lS5ny
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/** n# 7Pr/*0
* @author Joa \?fI t?
* YK#fa2ng
*/ 0\QR!*'$
publicclass Page { t T%/r,
A;X=bj _&a
/** imply if the page has previous page */ L:&k(YOBA
privateboolean hasPrePage; &(pjqV
TLa]O1=Bf.
/** imply if the page has next page */ X[$++p
.
privateboolean hasNextPage; P ,mN >
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/** the number of every page */ 'Prxocxq
privateint everyPage; IVxWxM*N<
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/** the total page number */ Z}6^ve
privateint totalPage; }?8uH/+ZA
Yl cbW0'c
/** the number of current page */ ~aK?cP
privateint currentPage; @* ust>7
ib6^x:HGU
/** the begin index of the records by the current F\JUx L@8
k+ o|0
query */ c,\i"=!$
privateint beginIndex; |bv,2uW z
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/** The default constructor */ !0VfbY9C
public Page(){ k=ytuV\
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} g{k1&|
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/** construct the page by everyPage %|W.^q
* @param everyPage ?X$,fQ#F|
* */ sN=6 gCau
public Page(int everyPage){ 7*o*6,/
this.everyPage = everyPage; /u<nLj 1
} Y-!YhWsS
Aj>[z8!,
/** The whole constructor */ g2cVZ!GIj
public Page(boolean hasPrePage, boolean hasNextPage, JAc_kl{4O
p
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int everyPage, int totalPage, q<vf,D@{ !
int currentPage, int beginIndex){ v5}X+'
this.hasPrePage = hasPrePage; $m$;v<PSe
this.hasNextPage = hasNextPage; d50Vtm\
this.everyPage = everyPage; alMYk
this.totalPage = totalPage; koG{
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this.currentPage = currentPage; ,U,By~s
this.beginIndex = beginIndex; R6;Phdh<>
} \/`?
)}v3q6?_
/** =HDI \LD<
* @return 5/><$06rq
* Returns the beginIndex. sfT+i;p
*/ /hW d/H]
publicint getBeginIndex(){ 66&EBX}
return beginIndex; C2U~=q>>
} RSfM]w}Hq#
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/** Lz9#A.
* @param beginIndex YB))S!;Ok
* The beginIndex to set. B/f0P(7
*/ `m@U!X
publicvoid setBeginIndex(int beginIndex){ }3 m0AQ;K
this.beginIndex = beginIndex; rnFM/GAy
} LHCsk{3
:t$aN|>y
/** \0;(VLN'U
* @return qNgd33u1
* Returns the currentPage. GOy%^:Xd
*/ /c#`5L[
publicint getCurrentPage(){ D87|q4
return currentPage; jn%kG ~]'Q
} t q50fq'
* A|-KKo\
/** LE^G&<!
* @param currentPage R0Ue0pF7
* The currentPage to set. +t)n;JHN
*/ l]!9$
publicvoid setCurrentPage(int currentPage){ iTo k[uJ}
this.currentPage = currentPage; }u{gR:lZ
} 6R UrF
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/** @ez Tbc3
* @return NtGn88='{
* Returns the everyPage. 9.O8/0w7LV
*/ a l9.}
publicint getEveryPage(){ >-<8N-@"n
return everyPage; O;Y:uHf
} (n{wg(R
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/** Rhzn/\)|
* @param everyPage qk(P>q8[
* The everyPage to set. `BFIC7a
*/ AN:@fZ
publicvoid setEveryPage(int everyPage){ %bXtKhg5eJ
this.everyPage = everyPage; SF]@|
} \a^,sV
C&\5'[*
/** p4u5mM
* @return oT95^y\9
* Returns the hasNextPage. HG>j5
*/ >?W[PQ5 yx
publicboolean getHasNextPage(){ yI{5m^s{
return hasNextPage; 6~meM@
} ~q +[<xR\
a@d=>CT$
/** 4B+9z^oQ
* @param hasNextPage donw(_=
* The hasNextPage to set. CR<`ZNuWz
*/ oSb, :^Wl
publicvoid setHasNextPage(boolean hasNextPage){ v`q\6i[-
this.hasNextPage = hasNextPage; PG5- ;i/
} 9<CG s3\
-5G)?J/*
/** \6|/RFT
* @return H %f:K2
* Returns the hasPrePage. :q##fG'm/
*/ =8G&3 R
publicboolean getHasPrePage(){ or ;f&![w
return hasPrePage; qUF'{K
} o;F" {RZ
ug 7o>PX
/** pe0x""K
* @param hasPrePage ^W83ByP
* The hasPrePage to set. Doze8pn
*/ 8
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publicvoid setHasPrePage(boolean hasPrePage){ Nf,Z;5e
this.hasPrePage = hasPrePage; =(AtfW^H
} &7?R+ZGo
;a"q'5+Ne
/** )(Iy<Y?#
* @return Returns the totalPage. -l+P8:fL~
* R/b4NGW@
*/ 8Q`WB0E<|
publicint getTotalPage(){ m,LG=s
return totalPage; 1-SVCk
-
} i hL/n
4NEq$t$Jn
/** >v;8~pgO
* @param totalPage {WN(&eax
* The totalPage to set. ZBD;a;wx
*/ Tz&Y]#h_
publicvoid setTotalPage(int totalPage){ pI`?(5iK6|
this.totalPage = totalPage; !SOrCMHx
} tEd.'D8 s
oj.A,Fh
} 5R$G(Ap_
pfuW
"kMzmo=Pv5
z1OFcqm
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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 10Wz,vW,n
`WEZ"5n
个PageUtil,负责对Page对象进行构造: tU wRE|_
java代码: ;Z[]{SQ
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/*Created on 2005-4-14*/ w^k;D,h
package org.flyware.util.page; $>M<j
l|`9:H
import org.apache.commons.logging.Log; Ko>&)%))$X
import org.apache.commons.logging.LogFactory; f},oj4P\
u#7+U\
/** ;#G oGb4AM
* @author Joa `L;eba
* xZ5M/YSyG
*/
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publicclass PageUtil { 8{U-m0v
!33#. @[
privatestaticfinal Log logger = LogFactory.getLog 31+;]W=
({0)@+V8
(PageUtil.class); X#a`K]!B
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/** ExSe=4q#
* Use the origin page to create a new page C8N{l:1f]
* @param page _zxLwU1(x
* @param totalRecords SxgYjIa-
* @return 9ILIEm:
*/ egR9AEJvz
publicstatic Page createPage(Page page, int g3@Rl2yQJ
"i.r@<)S
totalRecords){ 7fp(R&)1
return createPage(page.getEveryPage(), SDG-~(Y
B
(/U3}w-
page.getCurrentPage(), totalRecords); ~cAZB9Fa
} Oh.ZPG=
6}~pq1IF{
/** WlB'YL-`g
* the basic page utils not including exception sH,kW|D
`?*%$>W#"
handler ^da44Qqu
* @param everyPage :vx$vZb
* @param currentPage P27%xV-n>
* @param totalRecords |XYEn7^r
* @return page %x;x_
*/ LL^q1)o
publicstatic Page createPage(int everyPage, int Hi!Jj
mN`YuR~
currentPage, int totalRecords){ 5 /",<1
everyPage = getEveryPage(everyPage); Z.L?1V8Q1
currentPage = getCurrentPage(currentPage); yAT^VRbv
int beginIndex = getBeginIndex(everyPage, v1U?&C
uaw~r2
currentPage); JuRH>`
int totalPage = getTotalPage(everyPage, %Kh4m7
{n3EGSP#
totalRecords); <mA'X V,
boolean hasNextPage = hasNextPage(currentPage, pD"vRbYF
#BVtL :x@
totalPage); %z]U LEYrZ
boolean hasPrePage = hasPrePage(currentPage); h<<>3 A
u*S=[dq
returnnew Page(hasPrePage, hasNextPage, HysS_/t~
everyPage, totalPage, rj]F87"
currentPage, \mM<\-'p
2'jOP"G
beginIndex); \ b
V6@#,
} `cz2DR-"
%m,6}yt
privatestaticint getEveryPage(int everyPage){ })xp%<`
return everyPage == 0 ? 10 : everyPage; MvLs%GE%
} $yDWu"R8
S>G?Q_&}?D
privatestaticint getCurrentPage(int currentPage){ }UJv[
return currentPage == 0 ? 1 : currentPage; '# NcZy
} 2=0DCF;Bv
`=+^|Y}
privatestaticint getBeginIndex(int everyPage, int \?>Hu
v
1sE?YJP-
currentPage){ Z 2}ah
return(currentPage - 1) * everyPage; A61^[Y,dX_
} {u{@jp
*,C(\!b
!?
privatestaticint getTotalPage(int everyPage, int >FjR9B
#&<)! YY5
totalRecords){ #1c]PX
int totalPage = 0; h2z_,`iS7
cUqn<Z<n
if(totalRecords % everyPage == 0) TlAR.cV
totalPage = totalRecords / everyPage; <99M@ cF
else ^L1L=c;,
totalPage = totalRecords / everyPage + 1 ; "xcX'F^
f:*vr['d
return totalPage; lN,/3\B
} UX-&/eScN
]3ONFa
privatestaticboolean hasPrePage(int currentPage){ &uP~rEJl+
return currentPage == 1 ? false : true; ELrsx{p:
} M)*\a/6?{
n%h^o
privatestaticboolean hasNextPage(int currentPage, =/<LSeLxH
~pa!w?/bQ
int totalPage){ jA".r'D%
return currentPage == totalPage || totalPage == +[\eFj|=
G6VF>2
0 ? false : true; {NpM.;
} `&0Wv0D0
j Ja$a [
jVLA CWH
} h%WE=\,Qp
!8 &=y
]# t6Jwk
d]9U^iy
( mxT2"fC
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。 nEzf.[+9/
vVGDDDz/
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 =4GSg1Biy
'|;X0fD
做法如下: L
lqM c
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 yA{W
3+>G#W~
的信息,和一个结果集List: 2Q;9G6p
java代码:
2VW}9O
|t$Ma'P
+cb6??H
/*Created on 2005-6-13*/ TW !&p"Us+
package com.adt.bo; FP[!BUOf"
6c0>gUQx-
import java.util.List; T843":
,C3,TkA]
import org.flyware.util.page.Page; fs/*V~@
?` SUQm
/** >u9Nz0?j
* @author Joa )M2F4[vcb
*/ 8[6o (
publicclass Result { q7u'_R,;
= k\J<
private Page page; IK*07h/!
s/089jlc
private List content; h gJ[LU| >
\h8 <cTQ
/** zbJT&@z
* The default constructor ctcS:<r/3@
*/ 8,dBl!G=
public Result(){ `~eUee3b.~
super(); 4Qn$9D+?
} \W,I?Kx$
]qhPd_$?D'
/** dH( ('u[
* The constructor using fields #Fyuf,hw4
* $.]l!cmi%Q
* @param page Sp@-p9#
* @param content #m={yck *
*/ [$[:"N_
public Result(Page page, List content){ k{t`|BnPKB
this.page = page; Z0l+1iMx
this.content = content; w&ak"GgV
} Y3Q9=u*5
sH\5/'?
/** qx%}knB
* @return Returns the content. 7`u$
*/ 6-O_\Cq8
publicList getContent(){ 5h; +Ky!I
return content; mc4i@<_?
} {T].]7Z
jlxpt)0i
/** .1LCXW=
* @return Returns the page. y|wc,n%L>
*/ Sfdu`MQR
public Page getPage(){ d^`?ed\1
return page; itMg|%B%
} bV"G~3COy
1@$Ko5
/** m)oJFF
* @param content bJD;>"*
* The content to set. 6^DR0sO
*/ uG<}N=
public void setContent(List content){ Po%(~ )S>
this.content = content; )+fh-Ui
} RD.V'`n"
--DoB=5%8
/** %; D.vKoh
* @param page b".L_Ma1*
* The page to set. 7VP32Eh[
*/ B/n[m@O
publicvoid setPage(Page page){ M+x,opl
this.page = page; aFLO{t r`
} IY*EA4>
} 3)RsLI9
Qa.uMq
W|o'&
+$Rt+S BD
"]G\9b)
2. 编写业务逻辑接口,并实现它(UserManager, e#k<d-sf6
Pfs;0}h5
UserManagerImpl) D:K4H+ch
java代码: S<J}[I7V
}[xs~!2F
<wAFy>7
/*Created on 2005-7-15*/ %!1Q P[}K
package com.adt.service; Y&K;l_
F,'exuZ
import net.sf.hibernate.HibernateException; x)_0OR2lkp
Cn[0(s6
import org.flyware.util.page.Page; ^53r/V }%
k]I0o)+O.
import com.adt.bo.Result; +k>.Q0n%m
c?@T1h4
/** <Z/x,-^*<
* @author Joa +j4"!:N}B
*/ NG6& :4!
publicinterface UserManager { h3;bxq!q
Z@$8I{}G
public Result listUser(Page page)throws Nj 00W1
>_LDMs[-p
HibernateException; ?pzaG{
U,.![TP
} "T- `$'9
nxl[d\ap+n
y? co|
^) s2$A:L
|*0<M(YXN
java代码: s91JBP|B7
x UD-iSY
mOlI#5H
/*Created on 2005-7-15*/ Kc^;vT>3
package com.adt.service.impl; J`^I./
,YMp<C
import java.util.List; q')R4=0
K
.>IhN 5
import net.sf.hibernate.HibernateException; D= h)&
yYH 0v7vx+
import org.flyware.util.page.Page; qhz]Wm P
import org.flyware.util.page.PageUtil; E2{FK)qT
u5%7}<nNi
import com.adt.bo.Result; KFwzy U"
import com.adt.dao.UserDAO; h|"9LU4a
import com.adt.exception.ObjectNotFoundException; B[4KX
import com.adt.service.UserManager; G-.^O,%
k'5?M
/** _\GC(
* @author Joa fOMW"myQ
*/ 6Avw-}.7>
publicclass UserManagerImpl implements UserManager { 2j[&=R/.
K]9"_UnN
private UserDAO userDAO; BFOq8}fX2
u9EgdpD
/** +qwjbA+
* @param userDAO The userDAO to set. s=QAO!aw
*/ KSNPkd6
publicvoid setUserDAO(UserDAO userDAO){ [F6U+1n8e
this.userDAO = userDAO; <>aw
1WM+
} 7F{3*`/6
=^5Alba/
/* (non-Javadoc) wGP;Vbk
* @see com.adt.service.UserManager#listUser M!XsJ<jN/
O6G0
(org.flyware.util.page.Page) T]=r Co
*/ 07^iP>?
public Result listUser(Page page)throws X'qU*Eo
E`uY1B[c
HibernateException, ObjectNotFoundException { n@,G8=J?
int totalRecords = userDAO.getUserCount(); Xn%pNxUL
if(totalRecords == 0) PU1Qsb5
throw new ObjectNotFoundException Q{5kxw1ZF
AGYc |;
("userNotExist"); d!
LE{
page = PageUtil.createPage(page, totalRecords); "*srx]
List users = userDAO.getUserByPage(page); LB a[:j2
returnnew Result(page, users); c:o]d )S
} [CXrSST")E
T"DlT/\
} J.xPv)1'
sv&;Y\2c
U5.LDv;
;k>&FWEG
5MtLT#C3r
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 wlqpn(XR
jGpN,/VQa
询,接下来编写UserDAO的代码: +N:o-9
3. UserDAO 和 UserDAOImpl: Lja>8m
java代码: tAv@R&W,
2h1vVF3
O%5
r[
/*Created on 2005-7-15*/ h _+dT
package com.adt.dao; [Q/TlO t5
m;GbLncA
import java.util.List; [k;\S XDZo
<#u=[_H
import org.flyware.util.page.Page; U$WxHYo
=06gj)8
import net.sf.hibernate.HibernateException; #\ X#w<\?
=pS5uR~
/** C,ARXW1
* @author Joa 0dGAP
*/ @W[f1
publicinterface UserDAO extends BaseDAO { j)/nKh4O
H?&Mbw
d
publicList getUserByName(String name)throws 6sx'S?Qa*
,P70Jb
HibernateException; 5#+^E{
'+?"iVVo
publicint getUserCount()throws HibernateException; NnDxq%l%
[d1mLJAR
publicList getUserByPage(Page page)throws j/_s"}m{
XF;ES3 d
HibernateException; WSp
l0PZ`m+;j
} &3J_^210
XkXHGDEf 1
%t" CX5n
~M7y*'oY
LSGBq
java代码: MHX?@.
v
*KV0%)}sbL
X.f>'0i
/*Created on 2005-7-15*/ s'E2P[:
package com.adt.dao.impl; xp}hev^@$
^Eb.:}!D6
import java.util.List; tG9BfGF
]|zp0d=&o
import org.flyware.util.page.Page; $RIecv<e_
GVYBa_gx
import net.sf.hibernate.HibernateException; BGD8w2
import net.sf.hibernate.Query; naYrpK,.
%_RQx2
import com.adt.dao.UserDAO; .!$*:4ok
si`A:14R
/** aWWU4xe
* @author Joa h]5C|M|
*/ Jq&uF*!
public class UserDAOImpl extends BaseDAOHibernateImpl H%UL%l$
C":32_q
implements UserDAO { b&~4t/Vq
z(_Ss@ $
/* (non-Javadoc) U(Nu%
* @see com.adt.dao.UserDAO#getUserByName w)kNkD
Tx|Ir+f6L
(java.lang.String) +cgSC5nR
*/ !`g~F\l
publicList getUserByName(String name)throws \ 3wfwu.q
]>LhkA@V
HibernateException { #{?PbBE}
String querySentence = "FROM user in class %Y<| ;0v
FbaEB RM
com.adt.po.User WHERE user.name=:name"; ~]pE'\D7Ad
Query query = getSession().createQuery WN?O'E=2
\r /ya<5
(querySentence); h]+C.Eqnt#
query.setParameter("name", name); ,SynnE68
return query.list(); =(NB%}
} E^ P,*s
uC+V6;
/* (non-Javadoc) J&[@}$N
* @see com.adt.dao.UserDAO#getUserCount() U3T#6Rptl
*/ k2c}3 MeP
publicint getUserCount()throws HibernateException { 42e|LUZg
int count = 0; ,&jhlZ i
String querySentence = "SELECT count(*) FROM C${Vg{g7a
WN{ 9
user in class com.adt.po.User"; ?t/~lv
Query query = getSession().createQuery @wpN6 /
r=5{o1"
(querySentence); (]0%}$Fo
count = ((Integer)query.iterate().next (qqOjz
A+::O@_s
()).intValue(); ,uo'c_f(e
return count; pP*zq"o
} ]ndvt[4L
?nofUD.
/* (non-Javadoc) %+8F'&X
* @see com.adt.dao.UserDAO#getUserByPage %X4xv_o`f
eqP&8^HP
(org.flyware.util.page.Page) lG4H:[5V
*/ /2UH=Q!x4E
publicList getUserByPage(Page page)throws WFO4gB*
lsNrAA%m
HibernateException { zm]aU`j
String querySentence = "FROM user in class LQtj~c>X-|
uJFdbBDSh
com.adt.po.User"; 0~ZFv Wv
Query query = getSession().createQuery v@Gl|29_
M)eO6oX|
(querySentence); q}~3C1
query.setFirstResult(page.getBeginIndex()) p[hZ@f(z
.setMaxResults(page.getEveryPage()); @x"0_Qw
return query.list(); IhA5Wt0j
} w8kOVN2b
3&u&x(
} iz8Bf;
K8>zF/# +
l^|UCgRn
c0%"&a1]]V
>#hO).`C
至此,一个完整的分页程序完成。前台的只需要调用 PV9pa/`@
j Dy-)2<
userManager.listUser(page)即可得到一个Page对象和结果集对象 uT}' Y)m
Y( 3Bp\6
的综合体,而传入的参数page对象则可以由前台传入,如果用 FrTi+& <
}dp=?AFg
webwork,甚至可以直接在配置文件中指定。 A D1=[I3
o
Z%9_$Z
下面给出一个webwork调用示例: Zb1<:[
java代码: N F+iza;DP
/9HVY
%n
=at@ Vp/y
/*Created on 2005-6-17*/ lTd #bN
package com.adt.action.user; kPVO?uO
H-~6Z",1
import java.util.List; kKAP"'v
i%/Jp[e\W>
import org.apache.commons.logging.Log; #=6E\&NC
import org.apache.commons.logging.LogFactory; fjU8gV
import org.flyware.util.page.Page; B?4boF?~
lEhk'/~
import com.adt.bo.Result; yp$_/p O=2
import com.adt.service.UserService; Pb?$t
import com.opensymphony.xwork.Action; %kdEun
u/M+u;
/** w+yC)Rmz
* @author Joa Vm3v-=6
*/ S4G^z}{_
publicclass ListUser implementsAction{ XzIl`eH
ZaL.!g
privatestaticfinal Log logger = LogFactory.getLog B5X(ykaX~
<-[wd.M_
(ListUser.class); CbwJd5tk
j!]YNH@
private UserService userService; B)qWtMZx
s;3= {e.
private Page page; 8=gjY\Dp
a>GyO&+Dkg
privateList users; *T5!{
9 D7+[`r(-
/* \'|>p/5I
* (non-Javadoc) f}x.jxY?
* V+VkY3
* @see com.opensymphony.xwork.Action#execute() T~Gvp0r}h
*/ MM(xk
publicString execute()throwsException{ BK,{N0
Result result = userService.listUser(page); kzt(i Y_6
page = result.getPage(); `NgAT
3zq
users = result.getContent(); v"#mzd.tW
return SUCCESS; pKit~A,Q
} (=* cK-3
~v6OsH%vx
/** U$_xUG
* @return Returns the page. ][?G/*k
*/ [3{W^WSOz
public Page getPage(){ P] UJ0b
return page; {TX]\ufG
} e>(<eu~P
p2DrEId
/** Y#u}tE
d
* @return Returns the users. QlO0qbG[y
*/ b\-&sM(W"
publicList getUsers(){ E )5E$
return users; XqW@rU
} `kZ@Zmj#
_Jme!Oaa
/** lzYnw)Pv
* @param page 9hOJvQ2U]
* The page to set. iVy7elT;R
*/ V>A.iim
publicvoid setPage(Page page){ =gJb^
Gx(w
this.page = page; n#wI@W>%+
} (UU(:/
YRh BRE
/** `eIenA
* @param users +YqZ((
* The users to set. :yeq(oK,
*/ $+>M{fg?
publicvoid setUsers(List users){ lJE93rXU
this.users = users; N1|$$9G+
} }RwSp!}C
XI22+@d6
/** 3WUTI(
* @param userService K)\M5id]
* The userService to set. .h>8@5/s
*/ &<UMBAS
publicvoid setUserService(UserService userService){ (Nx;0"5IX
this.userService = userService; xv&Q+HD
} _c,'>aH=
} .R9IL-3fO
n(L\||#+
+ j W1V}h
z&{5;A}Q@
A` AaTP
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, p~9vP)74u
%YSu8G_t
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 `~ * @q!
DBT&DS
么只需要: [&nh5|f
java代码: LWHd~"eU
t| 'N+-T3
|j VM&R2s
<?xml version="1.0"?> l?Fb ='#
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ~Q>_uw}g#
5<ux6,E1{
1.0//EN" "http://www.opensymphony.com/xwork/xwork- sRrzp=D
hYM@?/(q
1.0.dtd"> 7g(F#T?;'
Vgyew9>E
<xwork> sH?/E6
YJl("MZ
<package name="user" extends="webwork- d\FJFMW*9
`zE}1M%y
interceptors">
stk9Ah
N~NQ6:R[
<!-- The default interceptor stack name Tp9-niW
+C(/Lyo}
--> r,Nq7Txn?
<default-interceptor-ref X0M1(BJgGo
hweaGL t0
name="myDefaultWebStack"/> -atGlu2
nE^Qy=iE
<action name="listUser" A6pjRxg
f4guz
class="com.adt.action.user.ListUser"> (<Th=Fns?
<param \0H's{uek
N]<!j$pOz
name="page.everyPage">10</param> !DI{:I_h(
<result Z+StB15
}QsZ:J.
name="success">/user/user_list.jsp</result> nYt/U\n!
</action> XxaGp95so
|-CnT:|o
</package> lZrVY+D
3^Q]j^e4Ny
</xwork> `St.+6^J
]d]JXt?)i
'D%w|Pe?Q
jh.@-
G_dsrpI=N
a+9*@z2
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 xGG,2W+z
_ %x4ty
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 6Vbzd0dk
R3!@?mcr
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 7]%Ypv$
8l"O(B'#Z
4
8{vE3JY
s-7RW
q;:6_Qr
我写的一个用于分页的类,用了泛型了,hoho v i)%$~
7rC uu *M
java代码: snt(IJQ
q,3;m[cA
_6Eu2|vM&
package com.intokr.util; {q3H5csFq
P/ oXDI8
import java.util.List; -.|4Y#b:&
62>zt2=
/** \i[BP
* 用于分页的类<br> 8p!*?RRme[
* 可以用于传递查询的结果也可以用于传送查询的参数<br> wfjc/u9W6R
* A~dQ\M
* @version 0.01 .Xdj(_&
* @author cheng /S\cU`ZVe
*/ 3<?XTv-
public class Paginator<E> { j2Pn<0U
privateint count = 0; // 总记录数 oQ7]=|
privateint p = 1; // 页编号 gs
W0
privateint num = 20; // 每页的记录数 b`_w])Y@
privateList<E> results = null; // 结果 6UE(f@
P=5NKg
/** o."rxd
* 结果总数 ?QA\G6i4
*/ h)v^q: ='
publicint getCount(){ ~=Ncp9ej#
return count; M]-VHI[&W
} m4[g6pNx~
L}j0a> =x4
publicvoid setCount(int count){ FhIqy %X
this.count = count; |7^^*UzSK:
} 3qQUpm+
/i)Hb`(S
/** )n=ARDd^e
* 本结果所在的页码,从1开始 G]Jz"xH#
* Q!M)xNl/
* @return Returns the pageNo. D^Ys)- d
*/ f'6|OsVQ
publicint getP(){ y)F!c29
return p; Fpt-V
} uvA(Rn
:ZxLJK9x1
/** A.Bk/N1G
* if(p<=0) p=1 }xlKonk
* $gMCR
b,
* @param p wE).>
*/ o7+>G~i
publicvoid setP(int p){ _N3}gFh>
if(p <= 0) Vj;
vo`T
p = 1; mo1
puU
this.p = p; [$ :
} Y~n`~(
!5x
Ly6=}
/** S2~@nhO`U(
* 每页记录数量 Y(GN4@`S
*/ NE"jh_m-
publicint getNum(){ LNQSb4
return num; /'y5SlE[J
} v@G4G*x\
|ZU#IQVQfn
/** 8o)L,{yl
* if(num<1) num=1 SvK1.NUa
*/ "uu)2Xe
publicvoid setNum(int num){ w 7tC|^#G
if(num < 1) yZSvn[f
num = 1; FQf#*
this.num = num; v5T9Y-{`
} N_C_O$j
OoP@-D"e
/** -Gsl[Rc0H;
* 获得总页数 !Y;<:zx5
*/ lVeH+"M?
publicint getPageNum(){ 'o\;x"YJ
return(count - 1) / num + 1; Z|^MGyn
} I{dl% z73
<<3+g"enno
/** q|q::q*
* 获得本页的开始编号,为 (p-1)*num+1 +0pW/4x
*/ Bt>}LLBS2
publicint getStart(){ PI7IBI
return(p - 1) * num + 1; v`{:~q*
} E_[ONm=,
J5T=!wF (
/** r`]7S_t5T
* @return Returns the results. A9BxwQU#
*/ @
t@|q
publicList<E> getResults(){ *1;23BiH-
return results; n0.8)=;2
} ?~qC,N [
e?)yb^7K
public void setResults(List<E> results){ k.Zll,s
this.results = results; T|f_~#?eV
} P,1exgq9
P$h;SK
public String toString(){ ZA.fa0n
StringBuilder buff = new StringBuilder h}6b&m
d5, FM
(); EHWv3sR-
buff.append("{"); #J.u
buff.append("count:").append(count); ^"`Z1)V
buff.append(",p:").append(p); z1vni'%J
buff.append(",nump:").append(num); /:6Q.onmLn
buff.append(",results:").append 5}SXYA}
5TET<f6R
(results); &9h
buff.append("}"); }9Qf #&o
return buff.toString(); 3^H/LWx`{]
} J_/05(48
0HPO"x3-O
} nB}e1
/_y
(qk5f`O
ZX]A )5G