Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 r/1(]#kOX
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 wS*E(IAl
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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 Mfs?x
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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 j39wA~K
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分页支持类: ME dWLFf
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java代码: W4N{S.#!
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package com.javaeye.common.util; he4(hX^
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import java.util.List; M`>E|"<
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publicclass PaginationSupport { >V~E]P%@
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publicfinalstaticint PAGESIZE = 30; ]{iQ21`a-
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privateint pageSize = PAGESIZE; "}!G!k:
#`IN`m|
privateList items; MJvp6n
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privateint totalCount; Jb(H %NJ
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privateint[] indexes = newint[0]; PM+[,H
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privateint startIndex = 0; G2Zer=rC
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public PaginationSupport(List items, int ise-O1'
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totalCount){ ?EL zj
setPageSize(PAGESIZE); ,)XLq8
setTotalCount(totalCount); _LPHPj^Pg
setItems(items); xwr8`?]y
setStartIndex(0); "8RSvT<W^5
} /\Ef%@
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public PaginationSupport(List items, int }}[2SH'nH
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totalCount, int startIndex){ :0ep(<|;
setPageSize(PAGESIZE); +H.`MZ=
setTotalCount(totalCount); R8Tx[CJ5
setItems(items); z}@7'_iJ
setStartIndex(startIndex); G#CXs:1pd+
} liZxBs
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public PaginationSupport(List items, int *Uh!>Iv;
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totalCount, int pageSize, int startIndex){ sRW<me;
setPageSize(pageSize); zTp"AuNHN
setTotalCount(totalCount); w@pPcZ>z/
setItems(items); =WLY 6)]A
setStartIndex(startIndex); SIllU
} yr6V3],Tp
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publicList getItems(){ R=dC4;
return items; O=lzT~G|4
} [ }:$yg
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publicvoid setItems(List items){ 6mE\OS-I
this.items = items; 4JEpl'5^Q
} ;*N5Y}?j'
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publicint getPageSize(){ N;d] 14|
return pageSize; -} +[
} TseGXYH
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publicvoid setPageSize(int pageSize){ *#2h/Q.
this.pageSize = pageSize; j+!v}*I![
} T+$[eWk"a
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publicint getTotalCount(){ H.;Q+A,8^
return totalCount; pw#-_
} @L`jk+Y0vF
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publicvoid setTotalCount(int totalCount){ GB^B r6
if(totalCount > 0){ 9$Y=orpWxr
this.totalCount = totalCount; fOHxtHM
int count = totalCount / 5N]"~w*
9^x> 3Bo
pageSize; UBs4K*h|
if(totalCount % pageSize > 0) KXrjqqXs
count++; i@q&5;%%
indexes = newint[count]; )_:NLo:
for(int i = 0; i < count; i++){ 1cDF!X]
indexes = pageSize * +mPx8P&%
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i; Kq!3wb;
} }b}m3i1
}else{ jCY%|
this.totalCount = 0; :]"V-1#}
} gIfh3 D=yX
} <%^&2UMg
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publicint[] getIndexes(){ [;N'=]`
return indexes; "7
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} yu|>t4#GT
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publicvoid setIndexes(int[] indexes){ 2eogY#
this.indexes = indexes; q)GdD==
} :3PH8TL
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publicint getStartIndex(){ xo)P?-
return startIndex; [UR-I0 s!/
} 6Zo}(^Ovz
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publicvoid setStartIndex(int startIndex){ pCDmXB
if(totalCount <= 0) W)/#0*7
this.startIndex = 0; 5G#n"}T
elseif(startIndex >= totalCount) ^q&x7Kv%
this.startIndex = indexes F@t3!bj9
,6/V"kqIP
[indexes.length - 1]; TC('H[
]
elseif(startIndex < 0) #mT"gs
this.startIndex = 0; 5-V pJ
else{ - LSWmrj
this.startIndex = indexes LeQjvW9y
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[startIndex / pageSize]; VTM/hJmwJ
} wzA$'+Mb
} =|=(l)8
}bDm@NU
publicint getNextIndex(){ bcyzhK=
int nextIndex = getStartIndex() + 1 zZlC#V
m 5.Zu.
pageSize; "%_+-C<L4
if(nextIndex >= totalCount) ]'cs.
return getStartIndex(); Xvv6~
else =l6mL+C
return nextIndex; #E?4E1bnB
} %>yL1BeA4
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publicint getPreviousIndex(){ M:8R-c#![
int previousIndex = getStartIndex() - `uFdwO'DD
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pageSize; b}f~il
if(previousIndex < 0) SBpL6~NW
return0; \zY!qpX<
else w
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return previousIndex; 45e~6",
} 7v kL1IA
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} dG{A~Z z
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抽象业务类 ok[i<zl;'
java代码: ixFi{_
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/** NUZl`fu1Z4
* Created on 2005-7-12 6<]lW
*/
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package com.javaeye.common.business; M+>u/fldV
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import java.io.Serializable; S!UaH>Rh
import java.util.List; 3<!7>]A
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import org.hibernate.Criteria; Ey2^?
import org.hibernate.HibernateException; 'V {W-W<
import org.hibernate.Session; A<{{iBEI`
import org.hibernate.criterion.DetachedCriteria; d~H`CrQE*
import org.hibernate.criterion.Projections; ?}0 ,o.
import |N2#ItBbW
tc! #wd+u
org.springframework.orm.hibernate3.HibernateCallback; uYN`:b8
import WLT"ji0w2
*VcJ= b
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org.springframework.orm.hibernate3.support.HibernateDaoS *p U x8yB
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upport; vQCy\Gi
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import com.javaeye.common.util.PaginationSupport; \85i+q:LuA
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public abstract class AbstractManager extends TDh5lI
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HibernateDaoSupport { = [E
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privateboolean cacheQueries = false; ?
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privateString queryCacheRegion; WcAkCH!L
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publicvoid setCacheQueries(boolean QV!up^Zso
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cacheQueries){ >A= f1DF
this.cacheQueries = cacheQueries; HtFDlvdy]
} [WmM6UEVS
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publicvoid setQueryCacheRegion(String h0$iOE
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queryCacheRegion){ l**X^+=$
this.queryCacheRegion = t_^4`dW`
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queryCacheRegion; ~}P,.QQ
} &ncvGDGi
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publicvoid save(finalObject entity){ AH^/V}9H
getHibernateTemplate().save(entity); w<#!h6Y=
} +[VXs~I
q
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publicvoid persist(finalObject entity){ kmW4:EA%
getHibernateTemplate().save(entity); Y4-t7UlS;
} J5qZFD
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publicvoid update(finalObject entity){ c)J%`i$
getHibernateTemplate().update(entity); ;uJMG
} 7! Nsm
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publicvoid delete(finalObject entity){ j%kncGS
getHibernateTemplate().delete(entity); (=0.in Z
} F8=+j_UGI
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publicObject load(finalClass entity, l#o
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finalSerializable id){ /:
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return getHibernateTemplate().load <)9y{J}s:
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(entity, id); 4Z*/WsCv
} )7F/O3Tq
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publicObject get(finalClass entity, m0wDX*Qn
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finalSerializable id){ sC'`~}C
return getHibernateTemplate().get G{}VPcrbC
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(entity, id); fhiM U8(&
} V
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publicList findAll(finalClass entity){ 79gT+~z
return getHibernateTemplate().find("from N8jIMb'<
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" + entity.getName());
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} Y2AJ+
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publicList findByNamedQuery(finalString x5Bk/e'
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namedQuery){ >:-$+I
return getHibernateTemplate (`^1Y3&2
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().findByNamedQuery(namedQuery); X?O[r3<
} @d'j zs
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publicList findByNamedQuery(finalString query, zhQJy?>'m
7!1S)dup
finalObject parameter){ 3]Ct6
return getHibernateTemplate (PLUFT
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().findByNamedQuery(query, parameter); oH@78D0A
} !$JT e
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publicList findByNamedQuery(finalString query, KlEpzJ98
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finalObject[] parameters){ *dQSw)R
return getHibernateTemplate ES[G
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().findByNamedQuery(query, parameters); i-1op> Y
} &C}*w2]0S
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publicList find(finalString query){ rq{$,/6.
return getHibernateTemplate().find }BEB1Q}L
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(query); 81F9uM0
} vM={V$D&
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publicList find(finalString query, finalObject $xsd~L&
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parameter){ E.h*g8bXe
return getHibernateTemplate().find NEs:},)o
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(query, parameter); ^iA9%zp
} 7V>M]
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public PaginationSupport findPageByCriteria *~`(RV
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(final DetachedCriteria detachedCriteria){ kJU2C=m@e2
return findPageByCriteria " bG2:
6BlXLQ,8q
(detachedCriteria, PaginationSupport.PAGESIZE, 0); JF]JOI6.e
} sOY:e/_F
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public PaginationSupport findPageByCriteria 42{~Lhxt
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(final DetachedCriteria detachedCriteria, finalint 7zMr:JmV
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startIndex){ BtZ yn7a
return findPageByCriteria sW$XH1Uf#
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(detachedCriteria, PaginationSupport.PAGESIZE, u*R_\*j@
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startIndex); z:O8Ls^\T
} pg.%Pdr<$
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public PaginationSupport findPageByCriteria DG/Pb)%Y
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(final DetachedCriteria detachedCriteria, finalint 9WHddDA
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pageSize, %O<BfIZ
finalint startIndex){ 2oW"'43X
return(PaginationSupport) }Z>)DN=+
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getHibernateTemplate().execute(new HibernateCallback(){ KoY F]
publicObject doInHibernate pAEx#ck
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(Session session)throws HibernateException { t^HRgY'NjM
Criteria criteria = *j=%
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detachedCriteria.getExecutableCriteria(session); Ac6=(B
int totalCount = %y@AA>x!
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((Integer) criteria.setProjection(Projections.rowCount 'qi}|I
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()).uniqueResult()).intValue(); 58K5ZZG
criteria.setProjection RSds8\tk
)jj0^f1!j
(null); J,G
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List items = QJNFA}*>
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criteria.setFirstResult(startIndex).setMaxResults V~bD)?M
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(pageSize).list(); ;<5q]/IHK
PaginationSupport ps = R]dg_Da
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new PaginationSupport(items, totalCount, pageSize, l:%GH
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startIndex); V)^+?B)T
return ps; +p^u^a
} neh(<>
}, true); "b[5]Y{
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} l,
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public List findAllByCriteria(final l2d{ 73h
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DetachedCriteria detachedCriteria){ 4 :=]<sc,
return(List) getHibernateTemplate a?.=V
@;kSx":b
().execute(new HibernateCallback(){ |}1dFp
publicObject doInHibernate hph4 `{T
h![#;>(
(Session session)throws HibernateException { f?b"i A(6
Criteria criteria = M;NX:mX9
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detachedCriteria.getExecutableCriteria(session); 1cGmg1U;
return criteria.list(); :LTN!jj
} nm+s{
}, true); G`zm@QL
} .2pK.$.
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public int getCountByCriteria(final $"&JWT!#
{)"vN(mX
DetachedCriteria detachedCriteria){ xpI wrJO
Integer count = (Integer) P$sxr
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getHibernateTemplate().execute(new HibernateCallback(){ m68*y;#
publicObject doInHibernate zVD:#d%b
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(Session session)throws HibernateException { [2koe.?(
Criteria criteria = b2]Kx&!
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detachedCriteria.getExecutableCriteria(session); qNr}
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return {U1m.30n
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criteria.setProjection(Projections.rowCount Q^I\cAIB
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()).uniqueResult(); ,PZ ge
}
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}, true); x :7IIvP
return count.intValue(); {|\.i
} _wOt39e&
} KF/-wZ"1s
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用户在web层构造查询条件detachedCriteria,和可选的 ? q&T$8zc4
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 '2O\_Uz
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PaginationSupport的实例ps。 b[7]F
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ps.getItems()得到已分页好的结果集 Df#l8YK#
ps.getIndexes()得到分页索引的数组 I0a<%;JJW
ps.getTotalCount()得到总结果数 &OBkevg
ps.getStartIndex()当前分页索引 uGt-l4
ps.getNextIndex()下一页索引 <,(,jU)j
ps.getPreviousIndex()上一页索引 KYP!Rs/j.
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 z] Ue|%K
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 d[35d J7F
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一下代码重构了。 ;$tSb ~K+
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我把原本我的做法也提供出来供大家讨论吧: g*"P:n71
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首先,为了实现分页查询,我封装了一个Page类: \L\b $4$d
java代码: 0RK!/:'
LK"69Qx?5q
* 4Izy14e
/*Created on 2005-4-14*/ yZ`wfj$Jj
package org.flyware.util.page; Y<rU#Z #T
Uwi7)
/** q]M0md
* @author Joa X76e&~
* }T$p)"
*/ f
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publicclass Page { 0LKRN|@
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/** imply if the page has previous page */ aATA9V
privateboolean hasPrePage; "Pf~iwfw
PuO&wI]:
/** imply if the page has next page */ hL5|69E
privateboolean hasNextPage; L:8q8i
IMfqiH)
/** the number of every page */ )/EO&F
privateint everyPage; 'ah[(F<*@e
\G3rX9xG
/** the total page number */ X|8c>_}
privateint totalPage; m9A!D
Bw{I;rW{2
/** the number of current page */ -GgA&dh
privateint currentPage; YDFyX){
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/** the begin index of the records by the current uH-)y,2&
BCcjK6'
query */ h=%_Ao<x
privateint beginIndex; AvHCO8h|
@gtQQxf"
pBPl6%C.X-
/** The default constructor */ !3v1bGk
public Page(){ 2"S}bfrX
xjUtl
} N&V`K0FU
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/** construct the page by everyPage d'I"jZ
* @param everyPage w'3iY,_ufC
* */ -S+zmo8
public Page(int everyPage){ {u9}bx'<
this.everyPage = everyPage; D1mfm.9_r^
} 2T TdH)
BRYHX.}h\A
/** The whole constructor */ ^KE%C;u
public Page(boolean hasPrePage, boolean hasNextPage, +t:0SRSt
(@}!0[[^
V#}kwON
int everyPage, int totalPage, 6Kb1~jY
int currentPage, int beginIndex){ jb;hcraR
this.hasPrePage = hasPrePage; r(2uu
this.hasNextPage = hasNextPage; Lu0x
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this.everyPage = everyPage; F*K_+
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this.totalPage = totalPage; _\HQvH
this.currentPage = currentPage; 'XBFv9&
this.beginIndex = beginIndex; 3<zp
} *
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/** F.v{-8GV
* @return g|Fn7]G
* Returns the beginIndex. C=4Qlt[`
*/ ,<p}o\6
publicint getBeginIndex(){ u4|$bbig
return beginIndex; y<bDTeoo
} Iy3GE[
7
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/** FtC^5{V+V
* @param beginIndex r{%qf;
* The beginIndex to set. 9pxc~=
*/ x~j`@k,;
publicvoid setBeginIndex(int beginIndex){ oFGhNk
this.beginIndex = beginIndex; {s{j~M
} w(TJ*::T
QW~1%`
/** V}NbuvDB@
* @return 1|6%evPu(
* Returns the currentPage. nL.<[]r
*/ J{&H+rd
publicint getCurrentPage(){ r_;Nt
return currentPage; =6|&Jt
} g^ i&gNDx
;
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/** _W'-+,
* @param currentPage ?_"ik[w}
* The currentPage to set. t\j*}# S
*/ E'.7xDN
publicvoid setCurrentPage(int currentPage){ 3CGp`~Zf
this.currentPage = currentPage; a,#j =
} B[?CbU
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/** 0|\$Vp
* @return Uwx
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* Returns the everyPage. Y0K[Sm>
*/ 1,!(0
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publicint getEveryPage(){ W#C*5@ 8
return everyPage; XJ5.
} rkY[E(SY
A;|D:;x3G
/** %zw1}|s#z
* @param everyPage >q1L2',pK
* The everyPage to set. -701j'q{
*/ GU8sO@S5#
publicvoid setEveryPage(int everyPage){ !V g`
this.everyPage = everyPage;
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} pDCeQ6?
KX7>^Bt&k
/** KC#q@InK
* @return g5QZ0Qkj
* Returns the hasNextPage. ?r 2` Q
*/ *6F[t.Or
publicboolean getHasNextPage(){ 58J}{Req
return hasNextPage; zb<6
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} q,eVjtF
BV upDGh3
/** !*. -`$x
* @param hasNextPage V2|aN<Sx<
* The hasNextPage to set. f|lU6EkU
*/ Zt.|oYH$
publicvoid setHasNextPage(boolean hasNextPage){ K_ ~"}
this.hasNextPage = hasNextPage; ^ tg<K
} =k0_eX0
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/** >R!jB]5
* @return 1sdLDw_)p
* Returns the hasPrePage. FXN/Yq
*/ ><$d$(
publicboolean getHasPrePage(){ in- HUG
return hasPrePage; "#oHYz3D
} zZ323pq
YCM]VDx4u1
/** #c?j\Y9nz
* @param hasPrePage +sUFv)!4
* The hasPrePage to set. *8_wYYH
*/ ,+{LYF
publicvoid setHasPrePage(boolean hasPrePage){ Pjjewy1}^
this.hasPrePage = hasPrePage; i,4>0o?
} lun\`f 5Q
M={V|H0
/** >P@H#=
* @return Returns the totalPage. 8tFoN*M
* EbE-}>7OO
*/ MgrLSKLT
publicint getTotalPage(){ $$5aUI:$~$
return totalPage; c>Xs&_
} QY?~ZwYB
j; y#[|
/** !F1N~6f
* @param totalPage (HE9V]
* The totalPage to set. 5Qn
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*/ ssRbhlD/*1
publicvoid setTotalPage(int totalPage){ E:}r5S)4
this.totalPage = totalPage; k $J zH$
} [knN:{ l
r^paD2&}
} ~%=MpQ3
5r8<7g:>C
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78# v
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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 QpA/SmJ
71gT.E
个PageUtil,负责对Page对象进行构造: E!l!OtFL
java代码: ^o1*a&~J@
`_RTw5{
-w_QJ_z_
/*Created on 2005-4-14*/ Xudg2t)+K
package org.flyware.util.page; _p&]|~a
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import org.apache.commons.logging.Log; )~] (&
import org.apache.commons.logging.LogFactory; ve/<=IR
Zo
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/** Oz`BEyb]{
* @author Joa D
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* ;y\IqiA{o
*/ (Dl$k Gn
publicclass PageUtil { cy3B({PLy
cKim-
privatestaticfinal Log logger = LogFactory.getLog 2h1C9n%j9
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(PageUtil.class); D.Q=]jOs
M#VE ]J
/** ps%q9}J
* Use the origin page to create a new page QQ ~-
* @param page LBsluT
* @param totalRecords v` 7RCg`
* @return ie\"$i.98H
*/ PCM-i{6/
publicstatic Page createPage(Page page, int WP+oFkw>
f Tl<p&b
totalRecords){ D+z?wuXk
return createPage(page.getEveryPage(), qA$*YIlK
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page.getCurrentPage(), totalRecords); S=nzw-(I
} @zz1hU
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/** fhp<oe>D
* the basic page utils not including exception qI<mjB{3`
'BPp ]R#{
handler 7MHKeLq
* @param everyPage &LVn6zAba
* @param currentPage j eX^}]x|%
* @param totalRecords s,n0jix@
* @return page ^!z[t\$
*/ <$~mE9a6
publicstatic Page createPage(int everyPage, int i Ae<&Ms
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currentPage, int totalRecords){ YmgLzGk`
everyPage = getEveryPage(everyPage); Vq;A>
currentPage = getCurrentPage(currentPage); ?yR&/a
int beginIndex = getBeginIndex(everyPage, &n?^$LTPY
9;Ox;;w
currentPage); :Q_<Z@2Y{
int totalPage = getTotalPage(everyPage, M9@ri ^x
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totalRecords); T {Uc:Z
boolean hasNextPage = hasNextPage(currentPage, xA$nsZ]
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totalPage); ~-m "
boolean hasPrePage = hasPrePage(currentPage); \z7SkZt,GT
rT5Ycm@
returnnew Page(hasPrePage, hasNextPage, 9Z'8!$LYg
everyPage, totalPage, q51Uf_\/
currentPage, p)3U7"q
9Fm"ei
beginIndex); e9[|!/./5
} 5qoSEI-m
ANSFdc
privatestaticint getEveryPage(int everyPage){ KiOcu=F
return everyPage == 0 ? 10 : everyPage; :WL'cJ9a
} #x3ujJ
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privatestaticint getCurrentPage(int currentPage){ 6 9NQ]{1
return currentPage == 0 ? 1 : currentPage; yz*6W
z D
} UHxE)]J
MR<;i2p
privatestaticint getBeginIndex(int everyPage, int C[Dav&=^F
aj,T)oDbt6
currentPage){ I=9!Rs(QF
return(currentPage - 1) * everyPage; E7)=`kSl
} _Bp1co85MQ
_b.qkTWUB
privatestaticint getTotalPage(int everyPage, int Adgc%
.#
*9c!^$V
totalRecords){ Fa_VKAq
int totalPage = 0; Y> Wu
/3:q#2'v
if(totalRecords % everyPage == 0) Nn"+w|v[ev
totalPage = totalRecords / everyPage; u(t#Ze~Y1
else ^:* 1d
\
totalPage = totalRecords / everyPage + 1 ; ?Wt$6{)
pd8Nke
return totalPage; 'ao"9-c
} s)2fG\1
{aC!~qR
privatestaticboolean hasPrePage(int currentPage){ X'% ;B
return currentPage == 1 ? false : true; QZhjb
} g
HbxgeL
6]pX>Xho
privatestaticboolean hasNextPage(int currentPage, Y.U[wL>
VZ](uF BY
int totalPage){ 1`9xIm*9w
return currentPage == totalPage || totalPage == !i%"7tQ3$
UaV iI/ks
0 ? false : true; {TRsd
} e$uiJNS2
UNi`P9D]3
"0k8IVwp
} P#/HTu5q7
h=_0+\%
v\"S
Gc
?9=9C"&s
Cssl{B
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。 4[-*~C|W5
-"[<ek
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 /q$,'^.A
mA@Me7m}
做法如下: P?]aWJ
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 {]]|5
\F
m&iH2|
的信息,和一个结果集List: Tl|:9_:t
java代码: (%:>T Q(
JHJ~X v
Q\,o:ZU_
/*Created on 2005-6-13*/ TbF4/T1b
package com.adt.bo; |xvy')(b
$<|lE/_]
import java.util.List; ?cEskafb>
3#45m+D
import org.flyware.util.page.Page; e=QK}gzX
uH;-z_Wpn!
/** D'hW|
* @author Joa {Pu\?Cq
*/ V)i5=bHC
publicclass Result { T}=>C+3r
awUx=%ERtA
private Page page; 4~OQhiJ
R?EASc!b
private List content; }AvcoD/b
N9<Ujom
/** h}Wdh1.M3
* The default constructor 1uk0d`JL
*/ 3o|I[!2.
public Result(){ ,mL
!(US
super(); =@5x"MOz
} Iu35#j
E|$Oha[
/** )CS.F=
* The constructor using fields `K
>?ju"
* oo$MWN8a>r
* @param page o(Cey7
* @param content 02k4N%
*/ xlR2|4|8
public Result(Page page, List content){ P0-Fc@&Y
this.page = page; l@hjP1o
this.content = content; Y}D onF
} =0'q!}._!
]k8/#@19
/** irZFV
* @return Returns the content. Kw`VrcwjT
*/ xyE1Gw`V
publicList getContent(){ j9/-"dTL
return content; 1lnU77;
} 7gS1~Q4\V2
$8BE[u|H2
/** U`x bPQ
* @return Returns the page. STA4 p6
*/ 2spg?]
public Page getPage(){ =4 X]gW
return page; ^R$'eG 4L?
} =[<m[.)i
g+C!kaC)
/** 5b6s4ZyV
* @param content ~/tKMS6T
* The content to set. Bfv.$u00p
*/ U^Tp6vN d
public void setContent(List content){ Pu>N_^ C
this.content = content; ^ 2u/n
} H2-28XGc
S2VVv$r_6
/** Q^Bt1C
* @param page D["MUB4l
* The page to set. 9%iFV
N'
*/ d=]U_+
publicvoid setPage(Page page){ ]> Y/r-!
this.page = page; qYp$fmj
} mEuHl>
} s2v(=
yO>V/5`
WnAd5#G
7e&\{*
:'r6TVDW
2. 编写业务逻辑接口,并实现它(UserManager, Y+/lX 6'
mi2o1"Jd$`
UserManagerImpl) Gr(|Ra.
java代码: 3|Y!2b(:?
~tGCLf]c\
cub<G!K
/*Created on 2005-7-15*/ G7* h{nE
package com.adt.service; cUDg M
!@
YXZ
import net.sf.hibernate.HibernateException; nD,{3B#
K.SeK3(
import org.flyware.util.page.Page; tO.$+4a
B">yKB:D}t
import com.adt.bo.Result; } IlP:
^i:\@VA:
/** ]R_G{%
* @author Joa cQFR]i
*/ twk&-:'
publicinterface UserManager { M}.b"
ljZ
i!MwBYk
public Result listUser(Page page)throws c/u_KJFF-n
}G1&]Wt_
HibernateException; ;~sr$6
y>(rZ^y&
} nb@" ?<L!
?|t/mo|K?
-'C!"\%
s=EiH
;>2#@QP
java代码: vg8O]
YF
BEw{X|7
5 z]\$=TE
/*Created on 2005-7-15*/ $ehg@WK}.
package com.adt.service.impl; v29G:YQe
"~p+0Xws9
import java.util.List; N5q725zJ
ZcZ;$*
import net.sf.hibernate.HibernateException; j.QHkI1.
z*.v_Mx
import org.flyware.util.page.Page; "jZm0U$,*
import org.flyware.util.page.PageUtil; Qm);6X
C;sgK
import com.adt.bo.Result; YlUpASW
import com.adt.dao.UserDAO; S]yvMj_?
import com.adt.exception.ObjectNotFoundException; XS0V:<+,
import com.adt.service.UserManager; ^&:'NR
O2H/rFx4
/** c)1=U_6 1
* @author Joa MtG_9-
*/ +(ny|r[#
publicclass UserManagerImpl implements UserManager { p~bkf>
3B,QJ&
private UserDAO userDAO; o?!uX|Fy
0MpS4tW0=
/** ~+m,im8}
* @param userDAO The userDAO to set. 9 )Yw
:
*/ 6D9o08
publicvoid setUserDAO(UserDAO userDAO){ E8tD)=1
this.userDAO = userDAO; y-cw~kNPP3
} /{G/|a
YhgUCF#
/* (non-Javadoc) d1NE% hg3
* @see com.adt.service.UserManager#listUser z`'P>.x
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(org.flyware.util.page.Page) La}o(7=s
*/ HP$K.a7H
public Result listUser(Page page)throws {Nq?#%vdT
Jf+7"![|
HibernateException, ObjectNotFoundException { UpeQOC
int totalRecords = userDAO.getUserCount(); q$^<zY
if(totalRecords == 0) M1uP\Sa
throw new ObjectNotFoundException /w~C~6z
@!
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("userNotExist"); @Qo,p
page = PageUtil.createPage(page, totalRecords); n|]N7 b'
List users = userDAO.getUserByPage(page); !3KPwI,
returnnew Result(page, users); kukaim>K
} d8.ajeN]o
+{xG<Wkltz
} FT_k^CC
WTu{,Q
v>^jy8$
|+/$ g.
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to
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Y\u_+CG*
/.-m}0h|W-
询,接下来编写UserDAO的代码: aL$j/SC
3. UserDAO 和 UserDAOImpl: B*Cb6'Q
java代码: 4sd-zl$Of
U$$3'n
8DT@h8tA
/*Created on 2005-7-15*/
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package com.adt.dao; 4[H,3}p9H
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import java.util.List; Y\>\[*.v
!47A$sQ
import org.flyware.util.page.Page; 'WzUu MCx
Q=XA"R
import net.sf.hibernate.HibernateException; $9m5bQcV
htg'tA^CtS
/** A[RN-R,
* @author Joa z9fNk%
*/ n8?KSQy$
publicinterface UserDAO extends BaseDAO { Hf.xd.Yw
s'AQUUrb<
publicList getUserByName(String name)throws D`fc7m
Wbs^(iUU}
HibernateException; 9!S^^;PN&
Deog4Ol"/
publicint getUserCount()throws HibernateException; d5q4'6o,
;;6\q!7`
publicList getUserByPage(Page page)throws 5{fwlA
:b,o B==%
HibernateException; ;y,NC2Xj
Qasr:p+
} ujNt(7Cz
vF+YgQ1H
t*rp3BIG
EUXV/QV{
iGyVG41U
java代码: 4Q/r[x/&C
A<;0L . J
I &cX8Tw
/*Created on 2005-7-15*/ Cd9t{pQD4
package com.adt.dao.impl; C*]AL/
n\
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import java.util.List; eFes+i( 35
5GUH;o1m
import org.flyware.util.page.Page; wz)m{:b<
=yo=q)W
import net.sf.hibernate.HibernateException; 4&H+hN{3
import net.sf.hibernate.Query; TVj1C
0vcET(
import com.adt.dao.UserDAO; #VQ36pCd
!
7Nn]Lx
/** /;b.-v&
* @author Joa x1:vUHwC
*/ lW&[mnR
public class UserDAOImpl extends BaseDAOHibernateImpl 6WCmp,*
KdS
eCeddW
implements UserDAO { frk7^5
i:R!T,
/* (non-Javadoc) "{mt?
* @see com.adt.dao.UserDAO#getUserByName )ZviS.
UVnrDhd!0
(java.lang.String) V~JBZ}`TG<
*/ *(>Jd|C
publicList getUserByName(String name)throws '>"`)-
}[
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HibernateException { Mn-<5 1.%
String querySentence = "FROM user in class _y|[Z;
AK%=DVkM
com.adt.po.User WHERE user.name=:name"; R+k=Ea&x
Query query = getSession().createQuery x ru(Le}E
d!w1t=2H
(querySentence); 0%#t[usY
query.setParameter("name", name); ?i/73H+;D3
return query.list(); uFMs^^#
} a =9vS{
o&WRta>VP
/* (non-Javadoc) GsR-#tV@
* @see com.adt.dao.UserDAO#getUserCount() a\.//?
*/ @ 8A{ 9i
publicint getUserCount()throws HibernateException { Hu[8HzJo
int count = 0; r
.{rNR
String querySentence = "SELECT count(*) FROM u;$I{b@M]
e1:u1(".
user in class com.adt.po.User"; a"MTQFm'
Query query = getSession().createQuery _QD/!~O
yIM.j;5:~5
(querySentence); yl[2et
count = ((Integer)query.iterate().next b;SFI^
YL;SxLY
()).intValue(); ,ZLG7e
return count; /IrKpmbq
} L;L2j&i%v)
9Kq<\"7Bmz
/* (non-Javadoc) 2#,8evH
* @see com.adt.dao.UserDAO#getUserByPage =mDy@%yx!
IJ+O),'
(org.flyware.util.page.Page) ~:R4))qpg
*/ -t;?P2
publicList getUserByPage(Page page)throws \CP*i_:"
Oz_b3r
HibernateException { B/kcb(5v
String querySentence = "FROM user in class &3!i@2d;3f
"4J?JR
com.adt.po.User"; wOD/Z8
Query query = getSession().createQuery X%RQB$
PEMxoe<+
(querySentence); |p'_k(z}
query.setFirstResult(page.getBeginIndex()) O@G<B8U,K
.setMaxResults(page.getEveryPage()); 1uK)1%vK
return query.list(); H57jBD
} l6r%nHP@
[N'r3
} d#x8O4S%i2
nhB^Xr=
E&}H\zt#
$Ui]hA-:?y
{jq^hM!TEy
至此,一个完整的分页程序完成。前台的只需要调用 ^!zJf7(+<>
/DgT1^&0
userManager.listUser(page)即可得到一个Page对象和结果集对象 <FMuWHY
,C5@P+A
的综合体,而传入的参数page对象则可以由前台传入,如果用 eh8<?(eK
@B}&62T
webwork,甚至可以直接在配置文件中指定。 Yb,G^+;
S(q4OQB{
下面给出一个webwork调用示例: e7)> U!9c9
java代码: z:@d@\$?
+]aD^N9['
w*]_FqE
/*Created on 2005-6-17*/ @]}Qh;a~
package com.adt.action.user; Udb0&Y1^
7lnM|nD
import java.util.List; o.v,n1Nm
Q*TQ*J7".X
import org.apache.commons.logging.Log; ]~4}(\u
import org.apache.commons.logging.LogFactory; 0TuNA\Ug+
import org.flyware.util.page.Page; b}"vIRz
6
d{D3e[p^
import com.adt.bo.Result; Y9lbf_51
import com.adt.service.UserService; *,Aa9wa{
import com.opensymphony.xwork.Action; fSgGQ
D4
0
/D5
/** uC <|T
* @author Joa &q"uy:Rd
*/ 7KYF16A4
publicclass ListUser implementsAction{ uWM4O@Qn)d
g[uE@Gaj&
privatestaticfinal Log logger = LogFactory.getLog x<)!$cg
?CL z@u~
(ListUser.class); _&8KB1~
)^QG-IM
private UserService userService; F~11 _
TLR Lng
private Page page; ul]m>W
$)WH^Ir~
privateList users; 1{Sx V
d@`-!"
/* qrORP3D@
* (non-Javadoc) }VJ hw*s
* Ezo" f
* @see com.opensymphony.xwork.Action#execute() 3 8ls 4v3
*/ )aO!cQ{s
publicString execute()throwsException{ \dQ2[Ek
Result result = userService.listUser(page); [{Klv&>_/
page = result.getPage(); o9(#KC?3
users = result.getContent(); 8tB{rK,
return SUCCESS; NR@SDW
} Xj(k(>7V
LT
y@6*
/** ;9- 4J
* @return Returns the page. 's%ct}y\J
*/ ir1RAmt%
public Page getPage(){ Jq=>H@il
return page; Qcy+ {j]
} ;_;H(%uY
NEjBjLJZ
/** '~!l(&X
* @return Returns the users. 'j=PbA
*/ 4'u|L&ow
publicList getUsers(){ .x9nWa
return users; |7 W6I$Xl
} >O[^\H!\
>goAf`sqo
/** EJ[iOYx
* @param page fjzr8vU}C
* The page to set. zv3<i (
*/ 4<!}4
publicvoid setPage(Page page){ yO69p
this.page = page; Zzzi\5&gU
} iJ~iJ'vf
|cBF-KNZ
/** ;/]c^y
* @param users u9[w~U#
* The users to set. ^9m^#"ZW`
*/ [pyXX>:M
publicvoid setUsers(List users){ j4hUPL7
this.users = users; ,_7tRkn
} r+WPQ`Ar
[zO(V`S2
/** <\#
* @param userService ^SelqX
* The userService to set. 6!Ap;O^*
*/ d+wNGN
publicvoid setUserService(UserService userService){ R;I-IZS:
this.userService = userService; $DMu~wwfG
} _jI)!rfb
} >0G}, S
$y |6<
s(DaPhL6Qm
_J$p<
6T
aT_29
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, mfi'>o#
z 4OR
UQ
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 -
G2M;]Cn
MLDg).5
么只需要: nCmrt*&}
java代码: d~oWu [F*
Ns] 9-D
3t}o0Ai9
<?xml version="1.0"?> >w2WyYJYH
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MjeI?k}LJ
#esu@kMU`
1.0//EN" "http://www.opensymphony.com/xwork/xwork- rzY@H }u
jMN@x]6w
1.0.dtd"> ^bgm0,M
ROiX=i
<xwork> !wufoK
"VOWV3Z
<package name="user" extends="webwork- '%/u103{e
*/m~m?
interceptors"> 2nz'/G
T<~[vjA
<!-- The default interceptor stack name G"R>a w
KPvYq?F>4
--> 6je%LHhL
<default-interceptor-ref ~\(>m=|C:H
NNrZb?
name="myDefaultWebStack"/> YedipYG9;
]m,p3
<action name="listUser" i!-sbwd7
r}M4()9L
class="com.adt.action.user.ListUser"> CX2q7azG
<param _|#|mb4Fe
iPL'JVPZ
name="page.everyPage">10</param> nylIP */
<result 5nw9zW
:'
,>EY9j
name="success">/user/user_list.jsp</result> +4vX+;: br
</action> JA2}
m!>'}z
</package> V0&QEul
by3kfY]4s
</xwork> EjCs
@Bwl)G!|
!f2>6}hE
D#AxgF_He
Ceb i9R[
?(hQZR
0e
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 `I<|*vW
u
_Dt TG<E
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。 O/"&?)[v
"qp_*Y
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 +Uk.|@b=-V
YZJP7nN
PQ|x?98
Sgy~Z^
q/zdd3a
我写的一个用于分页的类,用了泛型了,hoho 'hWRwP|
T}On:*&
java代码: >QPS0Vx[
8=Ht+Br
8eLL
package com.intokr.util; )&-+:u0
k9?+9bExXA
import java.util.List; 0:S)2"I58p
k}gs;|_
/** L0~O6*bk
* 用于分页的类<br> :.^rWCL2
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 9_$Odc%]
* ddxv.kIj.
* @version 0.01 hR{Zh>
* @author cheng EeJ]>
1
*/ n&JP/P3Y
public class Paginator<E> { 7Kjq1zl;
privateint count = 0; // 总记录数 ('oUcDOFTS
privateint p = 1; // 页编号 85]UrwlA4
privateint num = 20; // 每页的记录数 g?sFmD
privateList<E> results = null; // 结果 ~VKXL,.
N<%,3W_-_
/** 9NAlgET
* 结果总数 GC2<K
*/ +UtK2<^:o
publicint getCount(){ [5-5tipvWp
return count; pj6Cvq4bD
} TMBdneS-s
RB!E>]
publicvoid setCount(int count){ %{"STbO #>
this.count = count; B*7o\~5
} i:72FVo
2}-W@R
/** =G :H)i
* 本结果所在的页码,从1开始 71InYIed
* NGu]|p
* @return Returns the pageNo. +l\Dp
*/ Ns_d10rZ.
publicint getP(){ FqfeH_-U
return p; Yaqim<j
} kCV OeXv
5ZLH=8L
/** q!4dK4`#5
* if(p<=0) p=1 %k_JLddlW
* [sBD|P;M
* @param p e[n>U@
*/ hpU7
publicvoid setP(int p){ t@\0$V
\X
if(p <= 0) -oj@ c
OZ
p = 1; x8[8z^BV?e
this.p = p; Jx]`!dP3
} })Jp5vv
%Vq@WF
/** VQyDd~Za
* 每页记录数量 z3,z&Ra
*/ IaB
A 2
publicint getNum(){ 6O}r4*
return num; tF4"28"h
} Xs`/q}R
51A>eU|
/** H:`r!5&Qb5
* if(num<1) num=1 ?AEpg.9R-
*/ AbB%osz}Ed
publicvoid setNum(int num){ Z`D#L[z$
if(num < 1) 28-@Ga4
num = 1; q(C+D%xB
this.num = num; #/aWGx_
} wS4zAu
W\"cp[b
/** Kxg09\5i
* 获得总页数 MxY CMe4S[
*/ KF.?b]
publicint getPageNum(){ u+*CpKR}
return(count - 1) / num + 1; .gB#g{5+J
} G 2mv6xK'
\ZA%"F){
/** J4<- C\=4
* 获得本页的开始编号,为 (p-1)*num+1 B;EdLs}
*/ >y1/*)O9~
publicint getStart(){ F](kU#3"S
return(p - 1) * num + 1; PffRV7qU0
} ^T^fowt=r
]_-<[0
/** RAe:$Iv$!v
* @return Returns the results. >4;A(s`
*/ )ZT&V