Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $B7<1{<=W
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `mQY%p|
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 `x lsvK>
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 <P3r+ 1|R
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分页支持类: 2*vOo^f
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java代码: }IC$Du#
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package com.javaeye.common.util; :&mYz(1q
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import java.util.List; &9$0v" `H
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publicclass PaginationSupport {
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publicfinalstaticint PAGESIZE = 30; 6`]R)i]
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privateint pageSize = PAGESIZE; |A8Ar 7)
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privateList items; r42[pi]F
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privateint totalCount; mn{8"@Z
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privateint[] indexes = newint[0]; P!,\V\TY]
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privateint startIndex = 0; p>Ju)o
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public PaginationSupport(List items, int )F0_V
4
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totalCount){ #E2`KGCzW
setPageSize(PAGESIZE); Y$--Hp4
setTotalCount(totalCount); c,Zs.
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setItems(items); " 6~pTHT
setStartIndex(0); U>(5J,G
} aa_&WHXkt
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public PaginationSupport(List items, int y%|nE((
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totalCount, int startIndex){ Oo`P +S#
setPageSize(PAGESIZE); n]}+ :
setTotalCount(totalCount); i92{N$*x
setItems(items); kI<C\*N
setStartIndex(startIndex); ^LfCLI9Z
} ~2
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public PaginationSupport(List items, int k)'hNk"x
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totalCount, int pageSize, int startIndex){ q+x4Od3
setPageSize(pageSize); Y)N(uv6
setTotalCount(totalCount); Y:FV+ SI
setItems(items); ,cWO Ak
setStartIndex(startIndex); F4k<YU
} [@";\C_I
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publicList getItems(){ nUQcoSY#
return items; J{@gp,&e
} X;w1@4!
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publicvoid setItems(List items){ ::dLOf8o
this.items = items; `-D6:- ,w
} =3{h9
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publicint getPageSize(){ '# "Z$
return pageSize; C:hfI;*7
} >L$y|8O
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publicvoid setPageSize(int pageSize){ F]
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this.pageSize = pageSize; +#6WORH0S
} Eg3rbqM- 8
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publicint getTotalCount(){ R#
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return totalCount; r4gkSwy
} 5dMIv<#T`
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publicvoid setTotalCount(int totalCount){ j+*VP
if(totalCount > 0){ @!Il!+^3
this.totalCount = totalCount; teUCK(;23
int count = totalCount / Ar'}#6
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pageSize; 1HN_
if(totalCount % pageSize > 0) DOkEWqM!
count++; }1`Rq?@J
indexes = newint[count]; =oluw|TCe7
for(int i = 0; i < count; i++){ )"&-vg<
indexes = pageSize * ?p. dc~tZ
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i; x&l?Cfvv=
} lBR6O!sBP
}else{ Jb6rEV>
this.totalCount = 0; UIL5K
} 8.o[K
} Al3Hu-Hf;`
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publicint[] getIndexes(){ %pc0a^iB
return indexes; F@ZG| &
} 69cOdIt^D
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publicvoid setIndexes(int[] indexes){ wC{=o`v
this.indexes = indexes; v%/8pmZw;
} 6"|PJ_@P
K
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publicint getStartIndex(){ <z#r3J
return startIndex; C0 .Xp
} c500:OSB
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publicvoid setStartIndex(int startIndex){ j6/ 3p|E
if(totalCount <= 0) k5w+{iOh
this.startIndex = 0; ? Q.Y
elseif(startIndex >= totalCount) CLQ \Is^]
this.startIndex = indexes Yl&eeM
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[indexes.length - 1]; (^qcX;-
elseif(startIndex < 0) *7ap[YXZ\w
this.startIndex = 0; #E^ %h
else{ pP{b!1
this.startIndex = indexes e:AB!k^xp$
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[startIndex / pageSize]; FDbx"%A
} $
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} ,PJl32
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publicint getNextIndex(){ tOnaD]J
int nextIndex = getStartIndex() + :lgIu .
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pageSize; qlPjz*<h"H
if(nextIndex >= totalCount) d;D^<-[i
return getStartIndex(); q1r\60M
else [mw#a9
return nextIndex; /%=#*/E7
} Bpo~x2p
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5
publicint getPreviousIndex(){ U,RIr8 G
int previousIndex = getStartIndex() - Kl(}s{YFn.
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pageSize; 0 v/+%%4}
if(previousIndex < 0) d^ipf*aLC
return0; A
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else OTN"XKa$
return previousIndex; J-Sf9^G
} '!yyg#
b2U[W#
} (niZN_qv
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抽象业务类 3i>$g3G
java代码: b'3#FI=:
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/** 0<nKB}9
* Created on 2005-7-12 YX^{lD1Jj
*/ q/Q^\HTk
package com.javaeye.common.business; xS,):R
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import java.io.Serializable; D@DK9?#
import java.util.List; dH?pQ
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import org.hibernate.Criteria; :".!6~:2
import org.hibernate.HibernateException; tHJ1MDw'
import org.hibernate.Session; h2=zvD;
import org.hibernate.criterion.DetachedCriteria; Qksw+ZjY#{
import org.hibernate.criterion.Projections; %{zM> le9
import 8y|(]5
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org.springframework.orm.hibernate3.HibernateCallback; m6lNZb]
import JC>}(yQA
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org.springframework.orm.hibernate3.support.HibernateDaoS I*K^,XY+
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upport; E+E5`-V
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import com.javaeye.common.util.PaginationSupport; f8[2$i*cL
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public abstract class AbstractManager extends t9 &O0tpe
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HibernateDaoSupport { o<V-gS
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privateboolean cacheQueries = false; <@JU0Z"a=
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privateString queryCacheRegion;
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publicvoid setCacheQueries(boolean `kekc.*-[@
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cacheQueries){ 8 ehC^Cg
this.cacheQueries = cacheQueries; Xk7zXah
} E62*J$wN@
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publicvoid setQueryCacheRegion(String u6(7#n02
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queryCacheRegion){ =1\'xz}p?
this.queryCacheRegion = }d6g{`
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queryCacheRegion; w`!Yr:dU
} ORfA]I-u
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publicvoid save(finalObject entity){ UAcABL^2
getHibernateTemplate().save(entity);
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} W_iP/xL
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publicvoid persist(finalObject entity){ ?I7H ):
getHibernateTemplate().save(entity); d%]7:
} h[XGFz
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publicvoid update(finalObject entity){ q!O~*
getHibernateTemplate().update(entity); V!ajD!00
} (MxLw:AV
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publicvoid delete(finalObject entity){ \>YXPMIk
getHibernateTemplate().delete(entity); ke&c<3m
} "QiUuD=
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publicObject load(finalClass entity, hp>me*vzr
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finalSerializable id){ `bH Eu"(,
return getHibernateTemplate().load uQ8]j .0
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(entity, id); JVXBm]
} jkD5Z`D
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publicObject get(finalClass entity, 6fkL@It
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finalSerializable id){ r*tGT_/6
return getHibernateTemplate().get 2t(E+^~
):.]4n{L
(entity, id); DORFK
} .6/[X`*
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publicList findAll(finalClass entity){ !PQ@"L)p
return getHibernateTemplate().find("from nY~CAo/:
<Ft.{aNq$c
" + entity.getName()); pD &\Z~5T
} Uel*:c
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publicList findByNamedQuery(finalString +'lfW{E1t
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namedQuery){ $
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return getHibernateTemplate kM9E)uT>(<
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().findByNamedQuery(namedQuery); ?[T&y
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} I[F.M}5:z
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publicList findByNamedQuery(finalString query, | @ mZ]`p
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finalObject parameter){ gbSZ-
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return getHibernateTemplate wk-ziw
v,2{Vr
().findByNamedQuery(query, parameter); Llg[YBJ7>
} Xw![}L>
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publicList findByNamedQuery(finalString query, hd^?svID
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finalObject[] parameters){ *[ A%tj%
return getHibernateTemplate [!DLT6Qk
ea B-u
().findByNamedQuery(query, parameters); ?(R6}ab>K7
} ) tsaDG-E
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publicList find(finalString query){ %q:V
return getHibernateTemplate().find <k^h&1J#g
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(query); rZzto;NDS
} o"5R^a@
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publicList find(finalString query, finalObject FC)aR[
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parameter){ KDCq::P<
return getHibernateTemplate().find ybB/sShGM
w#-rl@JQ4
(query, parameter); NShA-G N5
} GJH6b7I
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public PaginationSupport findPageByCriteria B:SzCC.B
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(final DetachedCriteria detachedCriteria){ }_Jai4O
return findPageByCriteria {)-%u8J\`N
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); :~`E@`/
}
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public PaginationSupport findPageByCriteria 9ft7
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(final DetachedCriteria detachedCriteria, finalint uTn(fs)D
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startIndex){ UT>\u
return findPageByCriteria tn:9
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(detachedCriteria, PaginationSupport.PAGESIZE, V!~uGf
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startIndex); #&Biu}4D
} K);:+s-
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public PaginationSupport findPageByCriteria )eUb@Eu
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(final DetachedCriteria detachedCriteria, finalint {?#g*QF|^
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pageSize, fr:RiOPn
finalint startIndex){ 8=<d2u'
return(PaginationSupport) t7R; RF
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getHibernateTemplate().execute(new HibernateCallback(){ @8DA
publicObject doInHibernate 2j(w*k
q~
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(Session session)throws HibernateException { 8th G-
Criteria criteria = szWh#O5=
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detachedCriteria.getExecutableCriteria(session); +tl THK
int totalCount = m"jqHGFV
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((Integer) criteria.setProjection(Projections.rowCount hOw7"'# !
[x,_0-_
()).uniqueResult()).intValue(); 1p`XK";g
criteria.setProjection py@5]n%
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(null); |'1[\<MM3
List items = whxE[Xnv
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criteria.setFirstResult(startIndex).setMaxResults u:"mq.Q
8 =J6{{E
(pageSize).list(); b9`MUkGGd
PaginationSupport ps = $t[`}I
}
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new PaginationSupport(items, totalCount, pageSize, <Gs)~T#'
id GM%Faur
startIndex); UB(Q &U_
return ps; |67<h5Q1
} aBol9`6
}, true); u["Pg
} @cSz!E}
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public List findAllByCriteria(final Q%q_
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DetachedCriteria detachedCriteria){ :`oYD
return(List) getHibernateTemplate +9,"ne1'e
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().execute(new HibernateCallback(){ S9-K
publicObject doInHibernate E^Q|v45d
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(Session session)throws HibernateException { ^tae
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Criteria criteria = h6la+l?x
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detachedCriteria.getExecutableCriteria(session); )2u=U9
return criteria.list(); QvjsI;CQ-
} v8_HaA$5Y
}, true); =f=MtH?0y
} 9C3q4.$D
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public int getCountByCriteria(final |.)dOk,o
f;
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DetachedCriteria detachedCriteria){ Hi<{c
Integer count = (Integer) rEs,o3h?po
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getHibernateTemplate().execute(new HibernateCallback(){ [2.pZB
publicObject doInHibernate 4k<4=E
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(Session session)throws HibernateException { vsHY; [
Criteria criteria = o#H"tYP
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detachedCriteria.getExecutableCriteria(session); ;R 'OdQ$o
return CzST~*lH
A)s
criteria.setProjection(Projections.rowCount 3[aCy4O
P+,\x&Vr
()).uniqueResult(); Z!7#"wO9+V
} 8H3|^J
}, true); :Uj+iYE8Z8
return count.intValue(); Ah)_mxK
} .B_)w:oF
} 3($%A GKJ
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用户在web层构造查询条件detachedCriteria,和可选的 * t{A=Wk
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7AHEzJh"
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PaginationSupport的实例ps。 "JKrbgN@;L
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ps.getItems()得到已分页好的结果集 4Z1-RS
ps.getIndexes()得到分页索引的数组 ?4(uwXp
ps.getTotalCount()得到总结果数 a[[u>oHyd
ps.getStartIndex()当前分页索引 j*rra
ps.getNextIndex()下一页索引 UYD(++
ps.getPreviousIndex()上一页索引 %'%r.
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<s)+V6\E
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^SVdaQ{7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 l7
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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 2BsMFMIw1
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一下代码重构了。 b~y1'|}g
B/c_pRl;
我把原本我的做法也提供出来供大家讨论吧: `GUj.+u
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首先,为了实现分页查询,我封装了一个Page类: Fpzps!(;=
java代码: "ALR)s,1,
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/*Created on 2005-4-14*/ n*{e0,gp`
package org.flyware.util.page; CJ%bBL'.
J`Q#p%W
/** $DJp|(8
* @author Joa +^1HtI|y
* p&_Kb\}U
*/ fXS4&XU
publicclass Page { aM,>LKNbQ
GG/~)^VMe
/** imply if the page has previous page */ 0<Vw0%!
privateboolean hasPrePage; @{j'Pf'
=X2 Ieb
/** imply if the page has next page */ (|Y[5O)
privateboolean hasNextPage; [^A 93F
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/** the number of every page */ mrS:||,_
privateint everyPage; 6~ev5SD;f
Xv|~1v%s7
/** the total page number */ X0*
y8"
privateint totalPage; 9@nX 6\,
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/_R=
/** the number of current page */ "9Sxj
privateint currentPage; *+vS
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/** the begin index of the records by the current D"El6<3)h
5YQ4]/h
query */ <2HI. @^
privateint beginIndex; q UY;CEf
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vHCz_ FV
/** The default constructor */ Q>cLGdzO
public Page(){ wwF]+w%lOw
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} ]HgAI$aA,
!rlN|HB
/** construct the page by everyPage D[x0sly
* @param everyPage l
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* */ (@vu/yN
public Page(int everyPage){ n"Ot'1yr
this.everyPage = everyPage; '3 xvQFg
} ]6v6&YV
N5Eb.a9S
/** The whole constructor */ 9?:SxI;v
public Page(boolean hasPrePage, boolean hasNextPage, -4mUGh1dy
ff**) Xdh
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int everyPage, int totalPage, S^]i
int currentPage, int beginIndex){ H5j~<@STC
this.hasPrePage = hasPrePage; \SkCsE#H
this.hasNextPage = hasNextPage; 6=3}gd5
this.everyPage = everyPage; osB[KRT>("
this.totalPage = totalPage; ~vy_~|6s
this.currentPage = currentPage; f>g>7OsD]
this.beginIndex = beginIndex; B5hk]=Ud
} iEux`CcJ.
=5a~xlBjD
/** Q+*o-
* @return {0WLY@7 2?
* Returns the beginIndex. '=EaZ>=
*/ ExqI=k`Zs
publicint getBeginIndex(){ hs}nI/#
return beginIndex; SWvy<f4<
} Cp7 EJr~
eNY$N_P
/** _fz-fG 1
* @param beginIndex ;]3Tuq
* The beginIndex to set. r3<yG"J86
*/ *IJctYJaX
publicvoid setBeginIndex(int beginIndex){ <\|f;7/
this.beginIndex = beginIndex; Z#IRNFj
} 8
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*q{/`Z{wy
/** 9]r6V
* @return ZMQSy7
* Returns the currentPage. DJr{;t$7~
*/ {wiw]@c8
publicint getCurrentPage(){ !U>711$
return currentPage; v?F~fRH
} 6H\3
id8a#&t]
/** <ppM\$
* @param currentPage =ltT6of@o
* The currentPage to set. ]e@'9`G-'
*/ )=V0
publicvoid setCurrentPage(int currentPage){ %,Xs[[?i
this.currentPage = currentPage; N%'=el4L
} OWT5Bjl
3#}5dO
/** '\Z54$
* @return cd)yj&:?Bt
* Returns the everyPage. :jKDM
*/ pi[:"}m]/P
publicint getEveryPage(){ 23BzD^2a
return everyPage; k)oD
} hVo]fD|W
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/** 02q]^3
* @param everyPage fFudoIC
* The everyPage to set. 73OFFKbsk
*/ \2~Cn c*O
publicvoid setEveryPage(int everyPage){ v@TP_Ka
this.everyPage = everyPage; y[BUWas(
} jk,:IG
Eqj&SA
/** /DA'p [,
* @return 6 6WAD$8$
* Returns the hasNextPage. L6c=uN
*/ U@yn%k9
publicboolean getHasNextPage(){ [GJ_]w^}j
return hasNextPage; #)QR^ss)iw
} yyb8ll?@a
Dp4\rps
/** %GQPiWu
* @param hasNextPage nm2bBX,fh
* The hasNextPage to set. ?a+>%uWt
*/ ,r!_4|\
publicvoid setHasNextPage(boolean hasNextPage){ $e1==@
R
this.hasNextPage = hasNextPage; a[bu{Z]%
} 42kr&UY&
|{udd~oE&
/** gZF-zhnC
* @return GZ(
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* Returns the hasPrePage. 8%q:lI
*/ CqOvVv
publicboolean getHasPrePage(){ ^=Q/H
return hasPrePage; B%QvFxZz
} 6O uB}*
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/** E9JxntX
* @param hasPrePage _0p8FhNt
* The hasPrePage to set. {3cT\u
*/ yU]NgG=z:-
publicvoid setHasPrePage(boolean hasPrePage){ /@-!JF#g
this.hasPrePage = hasPrePage; Ey7SQb
} w'E&w)Z]
S) ZcH
/** ;5QdT{$H
* @return Returns the totalPage. Ry9kGdqO
* CmKbpN*
*/ |X@ZM
publicint getTotalPage(){ 1{{z[w#
return totalPage; ZqH.$nXP
} f*U3s N^y
%>u(UmFO
/** o|FjNL
* @param totalPage U7i WYdt$
* The totalPage to set. Hz39v44
*/ AlF"1X02
publicvoid setTotalPage(int totalPage){ Q |,(C0<G
this.totalPage = totalPage; If[4]-dq
} 8>Az<EF^=#
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} "X<vgM^:
+ve S~
oZm)@Vv;
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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 ;>YLL}]j
@$o.Z;83`r
个PageUtil,负责对Page对象进行构造: &/o4R:i
java代码: ?Vg251-H
jNRR=0
W6STjtT3P
/*Created on 2005-4-14*/ 5eS0
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package org.flyware.util.page; CWF(OMA
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import org.apache.commons.logging.Log; x~3N})T5
import org.apache.commons.logging.LogFactory; tgk] sQY
aTXmF1_n
/** nX
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* @author Joa REqQJ7a/
* ~^Ceru"<
*/ mmSC0F
publicclass PageUtil { oN3DM;
"&!7wH ,A
privatestaticfinal Log logger = LogFactory.getLog }XHB7,
|7XPu
(PageUtil.class); V
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/** vZhC_G+tGd
* Use the origin page to create a new page Bgw=((p
* @param page _"nzo4e0
* @param totalRecords V\Q=EsHj
* @return CYkU-
*/ B8J_^kd
publicstatic Page createPage(Page page, int 7T7
A[A\
l=+hs
totalRecords){ ,v<GSiO
return createPage(page.getEveryPage(), 7ns n8WN[
8rZJvE#c
page.getCurrentPage(), totalRecords); y^OT0mZkg
} pf&H !-M
| R\PQ/)
/** P_7QZ0k/
* the basic page utils not including exception OO$YwOKS
8s+9PE
handler >aw`kr
* @param everyPage 'c]Fhe fb
* @param currentPage Ddu1>"p-x
* @param totalRecords F"|OcKAA}h
* @return page 0[\sz>@
*/ VPC7Dh%.
publicstatic Page createPage(int everyPage, int 0Wd2Z-I
C_5o&O8Bc
currentPage, int totalRecords){ Ufw_GYxan
everyPage = getEveryPage(everyPage); Z|t`}lK
currentPage = getCurrentPage(currentPage); D^m`&asC
int beginIndex = getBeginIndex(everyPage, .{\lbI
oh^/)2W
currentPage);
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int totalPage = getTotalPage(everyPage, 3haR/YN
)~>
C1<
totalRecords); d2~*fHx_!
boolean hasNextPage = hasNextPage(currentPage, =qWcw7!"
q7#4e?1
totalPage); g]$e-X@k
boolean hasPrePage = hasPrePage(currentPage); P0 4Q_A
| XGj97#M
returnnew Page(hasPrePage, hasNextPage, S1vUP5cZ
everyPage, totalPage, -e2f8PV?3
currentPage, L<QjkFj
e9\eh? bPU
beginIndex); l.>3gjr
} A r=P;6J
v ?Ds|
privatestaticint getEveryPage(int everyPage){ vz~`M9^
return everyPage == 0 ? 10 : everyPage; ]cmq
} " z8iuF
y"I8^CA
privatestaticint getCurrentPage(int currentPage){ \3bT0^7B
return currentPage == 0 ? 1 : currentPage; hD*83_S
} w%2|Po5
S'
<X)
privatestaticint getBeginIndex(int everyPage, int 6P$jMjs
uUIjntSF(
currentPage){ 1#w'<}h#U
return(currentPage - 1) * everyPage; k00&+C
} E[=#Rw!*
{9c_T!c
privatestaticint getTotalPage(int everyPage, int O)FkpZc@9c
evQk,;pIm
totalRecords){ =JW.1;
int totalPage = 0; E*"-U!?)l2
QJH((
if(totalRecords % everyPage == 0) qx'F9I
totalPage = totalRecords / everyPage; t&>eZ"
else _xz>O[unf
totalPage = totalRecords / everyPage + 1 ; 'pa8h L
B]nu \!
return totalPage; ^[=1J
} >gTQD\k:D
ZUd*[\F~!
privatestaticboolean hasPrePage(int currentPage){ i6-&$<
return currentPage == 1 ? false : true; vEZd;40y
} XS_Ib\-50
}C'h<%[P
privatestaticboolean hasNextPage(int currentPage, qX"m"ko
ugy:^U
int totalPage){ c#L.I
return currentPage == totalPage || totalPage == b~td^
zI&).
0 ? false : true; k:yrh:JhB
} Rq[VP#
QUb#84
3E$h
W
} y,F|L?dIq
/ReOf<%B
(GJX[$@
] <y3;T\~
pKzrdw-!
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 [ApAd
@wTRoMHPQ
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 2tMa4L%@C
~&7 *<`7{
做法如下: PBY;SG~
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 0ZJN<AzbA
V }wh
的信息,和一个结果集List: p9Y`_g`
java代码: `]$H\gNI[8
,AuejMd
/8[T2Z!
/*Created on 2005-6-13*/ xN>+!&3%w
package com.adt.bo; FNHJHuTe
_OY<Hb3%M
import java.util.List; BnPL>11Y
qG8-UOUDt
import org.flyware.util.page.Page; '(fCi
Rap =&
/** j=V2~
xA6
* @author Joa V5up/ 6b,1
*/ 3BK_$Fy
publicclass Result { g7`uWAxZa
lfe^_`ij(+
private Page page; e)Pm{:E
'l41];_
private List content; Vd+5an?
G&,2>qxKR
/** EWp'zbWP
* The default constructor NVG`XL
*/ IEQ6J}L
public Result(){ 12 S[m~L%
super(); &Tn7
} dY$jg
*rmwTD"
/** U\`yLsKvH`
* The constructor using fields q,fk@GI'2
* =G-u "QJ6
* @param page E|BiK
* @param content tRzo}_+N
*/ #e5*Dr8
public Result(Page page, List content){ #M=d)}[
this.page = page; &4V"FHy2
this.content = content; V~ [I /Vi
} 1Jn:huV2
_^Lg}@t
/** ]M.)N.T
* @return Returns the content. ((E5w:=?
*/ }ej-Lu,b3
publicList getContent(){ *+>R^\uT
return content; xO XCCf/
} Fwfe5`9'
r/BiR0$E
/** >a5avSn
* @return Returns the page. K0\Wty0
*/ o](nK5?
public Page getPage(){ i \u"+:j
return page; ^`Qh*:T$
} }RY&f4&GV,
-E>se8 %"
/** !e(ZEV g
* @param content #Cz6c%yK
* The content to set. t.tdY
*/ bcy(
?(
public void setContent(List content){ Mb[4G>-v=
this.content = content; PdD|3B&
} yi9c+w)b
6P:H`
/** ;3k6_ub
* @param page C%+>uzVIw
* The page to set. `Ao;xOJ
*/ 8L}N,6gC4_
publicvoid setPage(Page page){ Zjh9jvsW
this.page = page; ?FRQ!R
} fl18x;^I
} gHzjI[WI
V7
dAB,:
_ Oe|ZQ
ofA6EmQ37
vaEAjg*To<
2. 编写业务逻辑接口,并实现它(UserManager, 59I}
tXIre-. 2}
UserManagerImpl) Oz1ou[8k
java代码: 6lc/_&0
fMFlY%@t
P$|DiiH
/*Created on 2005-7-15*/ mmn1yX:d
package com.adt.service; TAu*lL(F
Ev\kq>2O
import net.sf.hibernate.HibernateException; SY}iU@xo
n! (g<"
import org.flyware.util.page.Page; Q,A`"e#:
iAlFgOk'
import com.adt.bo.Result; AH(O"v`
fKY1=3
/** ~-w
* @author Joa <#9zc'ED:
*/ /@bLc1"
publicinterface UserManager { ~Zd n#z\
r,4V SyZF\
public Result listUser(Page page)throws 9/k?Lv
(d C<N3
HibernateException; &sx|sLw)
|k4ZTr]?
} q61
rNOw_
=w.#j-jR
g loo].z
h;KI2k_^
{&c%VVZb:Z
java代码: ~;;_POm
O:a$ U:
wzMWuA4vX
/*Created on 2005-7-15*/ Ye}y_W
package com.adt.service.impl; n~d`PGs?f
*/L;6_
import java.util.List; NW9k.D%
e-os0F
import net.sf.hibernate.HibernateException; 1*x4T%RF$
+Hb6j02#
import org.flyware.util.page.Page; G\H@lFh
import org.flyware.util.page.PageUtil; @$79$:q N
j1>77C3
import com.adt.bo.Result; x./jTebeO
import com.adt.dao.UserDAO; ma
}Y\(38
import com.adt.exception.ObjectNotFoundException; 2/BFlb
import com.adt.service.UserManager; #1zWzt|DW
_+8$=k2nM
/** }#
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* @author Joa 9_ Qm_
*/ <][|,9mw
publicclass UserManagerImpl implements UserManager { R^F99L
%;zWS/JhL
private UserDAO userDAO; 7q|(ZZa
M{7EFTy!y
/** _pNUI{De
* @param userDAO The userDAO to set. "7)F";_(^
*/ ryx<^q
publicvoid setUserDAO(UserDAO userDAO){ @ec QVk
this.userDAO = userDAO; r\[HR ^`
} )M]4p6Y
BsB}noN}
/* (non-Javadoc) U&Ay3/
* @see com.adt.service.UserManager#listUser \+MR`\|3
y Ht63z8'
(org.flyware.util.page.Page) ,[bcyf
*/ (>0d+ KT
public Result listUser(Page page)throws -lMC{~h\(S
nwN<Q\]S
HibernateException, ObjectNotFoundException { KX<RD|=
int totalRecords = userDAO.getUserCount(); jVRd[
if(totalRecords == 0)
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throw new ObjectNotFoundException D2!ww{t
LTtfOcrt
("userNotExist"); -r-`T
s
page = PageUtil.createPage(page, totalRecords); \lR~!6:
List users = userDAO.getUserByPage(page); =10t3nA1$
returnnew Result(page, users); -"a+<(Y
} &,&+/Sr11
~.x!st}
} @-b}iP<T
H[,.nH_>+
>M:5yk@
4g1u9Sc0
[1nI%/</>
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fJE ki>1
ooZ7HTP|
询,接下来编写UserDAO的代码: $zmES tcm
3. UserDAO 和 UserDAOImpl: v,|;uc+
java代码: FcW ?([l
\k1Wh-3
Gcs+@7!b
/*Created on 2005-7-15*/ Ya9uu@F
package com.adt.dao; (rwbF
xJ&StN/'
import java.util.List; 82)d.>
]K9x<@!
import org.flyware.util.page.Page; ;*Z
w}51
?>o39|M_w
import net.sf.hibernate.HibernateException; LOida# R
"W+4`A(/l
/** \R-u+ci$ZY
* @author Joa c>UITM=!I
*/ 2CxdNj
publicinterface UserDAO extends BaseDAO { ?|hzAF"U
0KDDAkR5R
publicList getUserByName(String name)throws ,Fr{i1Ky
-~(0:@o ;
HibernateException; u8<=FV3
x:2[E-
publicint getUserCount()throws HibernateException; 9i`LOl:;
tIr66'8
publicList getUserByPage(Page page)throws d ,QJf\fc"
VS).!;>z
HibernateException; A:NY:#uC
56bB~=c
} WJ.PPq>]F
F'#3wCzt
. t3@86xTJ
2#!$f_
ADBw" ? >
java代码: S,8zh/1y
FD@! z
:
k2@IJ~
/*Created on 2005-7-15*/ P!O#"(r2]
package com.adt.dao.impl; K0E;4r
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yAL
import java.util.List; 1QN]9R0`#7
W.67, 0m$
import org.flyware.util.page.Page; &1[5b8H;+
Xl aNR+
import net.sf.hibernate.HibernateException; ]52_p[hZ}<
import net.sf.hibernate.Query; lT:<ZQyjT
rzTyHK[
import com.adt.dao.UserDAO; 3?geJlD4
7]v-2
*
/** wM&G-~9ujk
* @author Joa fzKKK+
*/ 8p211MQ<
public class UserDAOImpl extends BaseDAOHibernateImpl Z0'3.D,l
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implements UserDAO { b]Y,& 8}[+
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/* (non-Javadoc) v[|iuOU
* @see com.adt.dao.UserDAO#getUserByName 9]YmP8
n)=&=Uj`f
(java.lang.String) \ D[BRE+
*/ vB
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publicList getUserByName(String name)throws QAJ>93
@KpzxcEoO
HibernateException { 7uDUZdJy
String querySentence = "FROM user in class T#BOrT>V
14&EdTG.
com.adt.po.User WHERE user.name=:name"; foFn`?LF
Query query = getSession().createQuery aH$~':[93
:qZ^<3+:
(querySentence); @fK`l@K
query.setParameter("name", name); ='JX_U`A^F
return query.list(); *=
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} + mcN6/
2
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/* (non-Javadoc) oD 8-I^
* @see com.adt.dao.UserDAO#getUserCount() OiOL4}5(
*/ %x *f{(8h
publicint getUserCount()throws HibernateException {
@3@%9E
int count = 0; ;F+%{LgKl
String querySentence = "SELECT count(*) FROM .Sn1YAhE
f65Sr"qB3
user in class com.adt.po.User"; D[r
Query query = getSession().createQuery J91`wA&r
:d#NnR0^L
(querySentence); Kaa*;T![
count = ((Integer)query.iterate().next =,'Z6?%p
8vRiVJ8QS:
()).intValue(); lrE0)B5F
return count; M,@SUu v"
} O92Y d$S
QE gv,J{
/* (non-Javadoc) 0%t|?@HoN
* @see com.adt.dao.UserDAO#getUserByPage eXd(R>Mx
tWiV0PTI
(org.flyware.util.page.Page) bDo'hDmW
*/ CQ`(,F3(
publicList getUserByPage(Page page)throws J53;w:O
~V&ReW/
HibernateException { 'YG`/@n;
String querySentence = "FROM user in class ^\?9W
J$Q-1fjj
com.adt.po.User"; E)P1`X
Query query = getSession().createQuery uM}O8N
YZ>cE#
(querySentence); g)9/z
query.setFirstResult(page.getBeginIndex()) -0`hJ_(
.setMaxResults(page.getEveryPage()); n`,Q:
return query.list(); kUt9'|9!
} m&q;.|W
39j d}]e
} #r:`bQ0;
rA`\we)
$ZU(bEUOG
hLvv:C@
Vk (bU=w
至此,一个完整的分页程序完成。前台的只需要调用 5dF=DCZ
,7(/Il9
userManager.listUser(page)即可得到一个Page对象和结果集对象 `O{Uz?#*x
$-RhCnE
的综合体,而传入的参数page对象则可以由前台传入,如果用 "!tB";n
Mb>XM7}PU
webwork,甚至可以直接在配置文件中指定。 +7^Ul6BB#K
ttnXEF
下面给出一个webwork调用示例: 3(:mRb}
java代码: v,+@
U6i
0Nu]N)H5<l
,&=`T7i
/*Created on 2005-6-17*/ _iu|*h1y
package com.adt.action.user; rieQ&Jt"
}'W^Ki$
import java.util.List; |
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e
qM0MSwvC=
import org.apache.commons.logging.Log; 76b7-Nj"
import org.apache.commons.logging.LogFactory; 1Tq$ E[
import org.flyware.util.page.Page; &EPEpN
R
v~\ 45eEA
import com.adt.bo.Result; dx}/#jMa
import com.adt.service.UserService; IJ8DN@w9
import com.opensymphony.xwork.Action; :RsPGj6
cPcV[6)5K9
/** Yg[IEy
* @author Joa S nHAY<
*/ l5[xJH
publicclass ListUser implementsAction{ ".%LBs~$
;ZJ,l)BNO
privatestaticfinal Log logger = LogFactory.getLog
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E/ZJ\@gzD
(ListUser.class);
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1Ol]^'y7)
private UserService userService; ugB{2oq i
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private Page page; [bG>qe1}&
$O'2oeM
privateList users; *fSM' q;
%j">&U.[
/* p2vBj. *J
* (non-Javadoc) )6&\WNL-x
* pT@!O}'$
* @see com.opensymphony.xwork.Action#execute() S I7B6c
*/ 8>Z$/1Mh
publicString execute()throwsException{ es[5B* 5
Result result = userService.listUser(page); ?(q*U!=
page = result.getPage(); rx>Tc#g
users = result.getContent(); 49oW 'j
return SUCCESS; 2^6TrZA7M6
} #2jn4>
*\KMkx
/** <IyLLQ+v
* @return Returns the page. w3qf7{b
*/ _[i=TqVmf
public Page getPage(){ !rg0U<bO!
return page; @>2rz
} V6MT> T
82za4u$q#
/** U;{,lS2l
* @return Returns the users. MQ(/l_=zQ
*/ W 8$=a
publicList getUsers(){ i?>>
9f@F
return users; B"m:<@ "
} Kxc$wN<
O2]r]9sh*
/** =6<w'>
* @param page ;b?+:L
* The page to set. &8+6!TN7
*/ V-;nj,.mY
publicvoid setPage(Page page){ 3B".Gsm)X
this.page = page; (4ci=*3=
} CY3 \:D0I
8[1DO1*P
/** sN1*Zp'(
* @param users :F>L;mp
* The users to set. LnTe_Q7_
*/ 90iW-"l+[
publicvoid setUsers(List users){ l ~4e2xoT
this.users = users; /;nO<X:XV
} 2${,%8"0s
m0\"C-Bk
/** S~rVRC"<xo
* @param userService aC yb-P
* The userService to set. .;Utkf'I
*/ p
(xD/E
publicvoid setUserService(UserService userService){ _jrA?pY
this.userService = userService; Z"~6yF
} uP{+?#a_-\
} P}+|`>L
xUo)_P\_
,rFLpQl
vg:J#M:
.l( r8qY#
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, M-Z6TL
$sc8)d\B
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 y:|.m@
j1
?Y0$X>nm
么只需要: av;
(b3Lq
java代码: M,\|V3s
)/WA)fWkT
Ec*--]j*c
<?xml version="1.0"?> $qlqWy-s
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork p=-B~:
?%dCU~ z
1.0//EN" "http://www.opensymphony.com/xwork/xwork- bpF@}#fT
|T$a+lHMD
1.0.dtd"> /[|}rqX(
GATP
<xwork> )|Vg/S
b*FU*)<4.
<package name="user" extends="webwork- SEQO2`]e:
lYZ@a4TA
interceptors"> GrLM${G
c(Uj'uLc
<!-- The default interceptor stack name U)`3[fo
+A'q#~yILa
--> Jl}!CE@-
<default-interceptor-ref |,a%z-l
LTYuxZ
name="myDefaultWebStack"/> EAC(^+15K
K^,&ub.L)
<action name="listUser" U|
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0K$WSGB?6j
class="com.adt.action.user.ListUser"> 0l(E!d8&'
<param 2yJ7]+Jd7Y
KtfkE\KP
name="page.everyPage">10</param> q-3J.VLJ5H
<result G {pP}
dEQReD
name="success">/user/user_list.jsp</result> |%:qhs,
</action> )~?S0]j}
=0s`4Y"+
</package> f#;ubfi"z
L_
Xn,
</xwork> hpqHllL
,NaV
["9$
n~"g'Y
a8bX"#OR&N
u,Q_WR-wJ
nj~$%vmA
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 pu2 wEQ
,);=
(r9
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 , `[Z`SUk`
Qe @A5#
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 =e-a&Ep-z
S<y>Y
I5TQ>WJbf
u:AfHZ
CzzUi]*Ac{
我写的一个用于分页的类,用了泛型了,hoho w|
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F,L82N6\U
java代码: R<y Nv
SmT+L,:D
6:|!1Pg5
package com.intokr.util; <i{m.pR>
8`AcS|k
import java.util.List; uGuc._}=
Yn IM-
/** ~>N`<S
* 用于分页的类<br> `eMrP`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 1BMV=_
* tf$PaA
* @version 0.01 ~!3t8Hx6
* @author cheng [0% yJH
*/ NSMjr_
public class Paginator<E> { R
(tiIo
privateint count = 0; // 总记录数 :c~9>GCE&
privateint p = 1; // 页编号 PSP1>-7)w
privateint num = 20; // 每页的记录数 fB;&n
privateList<E> results = null; // 结果 5(iSOsb
IKMsY5i
/** 36kc4=
* 结果总数 QoW(tM
*/ dT0^-XSY
publicint getCount(){ vWqyZ-p,q
return count; vI
pO/m.3
} 2p$n*|T&c
\yJZvhUk
publicvoid setCount(int count){ @ 7Q*h
this.count = count; RMS.1: O
} VL_)]LR*)
4f{[*6 GX
/** k8InbX[
* 本结果所在的页码,从1开始 b[J-ja.
* Eonq'Re$
* @return Returns the pageNo. %K&+~CJE
*/ %mK3N2N$
publicint getP(){ L?3VyBE
return p; l]a^"4L4`o
} lF;ziF
Z #.GI
/** W; 3
R;
* if(p<=0) p=1 1?D8|<
* "jl1.Ah
* @param p {&\J)oZ
*/ X;s3y{ku
publicvoid setP(int p){ t/v@vJ`vSH
if(p <= 0) nu4Pc
p = 1; =,&u_>Dp
this.p = p; G]L0eV
} ) >>u|#@z
92P,:2`a
/** VRtbHam
* 每页记录数量 &%|xc{i
*/ i;[h
9=\/
publicint getNum(){ R7E]*:0}
return num; D 7Gd%
} f0-RhR
&q," !:L]
/** >QYh}Z-/%
* if(num<1) num=1 ;el]LnV!O
*/ 5S&aI{;9<
publicvoid setNum(int num){ q
Axf5
if(num < 1) L]c 8d
num = 1; uHfhRc9
this.num = num; lSZ"y
Q+
} +
$k07mb\
O]e6i%?
/** 2^zg0!z
* 获得总页数 7^kH8qJ)
*/ RtW4n:c
publicint getPageNum(){ $?H]S]#|}.
return(count - 1) / num + 1; M?E9N{t8)a
} 68vxI|EZ
?~F]@2)5w
/** 2"T8^r|U
* 获得本页的开始编号,为 (p-1)*num+1 98D{{j92
*/ X?KGb{
publicint getStart(){ k)$iK2I
return(p - 1) * num + 1; IL!BPFG w
} `y1BTe&
aj&\CJ
/** yQu vW$
* @return Returns the results. `^O'V}T
*/ hWe}'L-
publicList<E> getResults(){ y\[L?Rmd
return results; .(`(chRa}
} '9^E8+=|
! a86iHU
public void setResults(List<E> results){ \ua9thOG
this.results = results; X32RZ9y
} 5/Ydv
RB67
FpP\-+Sl
public String toString(){ slu$2-H
StringBuilder buff = new StringBuilder 08`f7[JQo]
?+3R^%`V
(); \U==f&G?J
buff.append("{"); =ft9T&ciD
buff.append("count:").append(count); \V._Z>]
buff.append(",p:").append(p); 9 1BY]N
buff.append(",nump:").append(num); `ffj8U
buff.append(",results:").append l>A\V)
5kK=S
(results); @[n2dmj
buff.append("}"); _Mlhumt
return buff.toString(); x2Ha&
} aZ8h[#]7
?(]a*~rx
} RwUW;hU
Vz%"9`r
S*;#'j)4+