Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 `o- <,
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 @)Y7GM+^
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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 k3eN;3#&
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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 U*l>8
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分页支持类: IWd*"\L
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java代码: 0|k[Wha#
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package com.javaeye.common.util; !I
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import java.util.List; (8/xSOZ[
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publicclass PaginationSupport { J@-9{<
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publicfinalstaticint PAGESIZE = 30; p 8rAtz>=J
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privateint pageSize = PAGESIZE; 3hjwwLKG$
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privateList items; gpl!Iz~5
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privateint totalCount; CawVC*b3
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privateint[] indexes = newint[0]; 8hV:bz"
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privateint startIndex = 0; JB}h}nb
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public PaginationSupport(List items, int 'v5gg2
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totalCount){ ?NeB_<dLa`
setPageSize(PAGESIZE); {[#
setTotalCount(totalCount); !7|9r$
setItems(items); BE;iC.rW
setStartIndex(0); ou4?`JF)-
} 1@Gv`{v
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public PaginationSupport(List items, int $*> _0{<
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totalCount, int startIndex){ &WS%sE{p_
setPageSize(PAGESIZE); =i<(hgD
setTotalCount(totalCount); )^3655mb
setItems(items); o*8 pM`uw
setStartIndex(startIndex); W{2y*yqY
} 6d6SP)|j
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public PaginationSupport(List items, int )]Rr:i9n
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totalCount, int pageSize, int startIndex){ &KwtvUN{
setPageSize(pageSize); XS@6jbLE
setTotalCount(totalCount); A}O9e
setItems(items); D7wWk
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setStartIndex(startIndex); e70*y'1fu
} %oQj^r!Xd
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publicList getItems(){ H2-(
return items; bBL"F!.
} }3e+D
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publicvoid setItems(List items){ P40eK0e6
this.items = items; S d -+a
} *8+YR
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publicint getPageSize(){ }Qo8Xps
return pageSize; b?,y%D)'
} AG%aH=TKp
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publicvoid setPageSize(int pageSize){ <taW6=;c
this.pageSize = pageSize; tc Z~T
} ggWfk
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publicint getTotalCount(){ 4G2V{(@QiZ
return totalCount; \v_(*
} U^I'X7`r
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publicvoid setTotalCount(int totalCount){ pj`-T"Q
if(totalCount > 0){ pDT6>2t
this.totalCount = totalCount;
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int count = totalCount / eA_4,"{
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pageSize; ujedvw;sO
if(totalCount % pageSize > 0) ^}#!?"Y
count++; KYaf7qy]
indexes = newint[count]; D=$<Ex^p
for(int i = 0; i < count; i++){ ml2HA4X&$Y
indexes = pageSize * 8V=o%[t
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i; TUt)]"h<
} fAi113q!
}else{ d29HEu
this.totalCount = 0; P^ VNB
} b6ddXM\Z
} 9#7zjrB
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publicint[] getIndexes(){ V8/o@I{U[
return indexes; nEYJ?_55
} bC|~N0b
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publicvoid setIndexes(int[] indexes){ TMrmyvv
this.indexes = indexes; '}=M~
} 5s9~rm
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publicint getStartIndex(){ {lA@I*_lj
return startIndex; mdd~B2"el
} JB7]51WH@
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publicvoid setStartIndex(int startIndex){
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if(totalCount <= 0) YL+W4ld
this.startIndex = 0; RPu-E9g@
elseif(startIndex >= totalCount) `:&{/|uP7
this.startIndex = indexes YH9BJ
KK}&4^q
[indexes.length - 1]; B5hGzplS
elseif(startIndex < 0) -JK+{<
this.startIndex = 0; rm7UFMCR6i
else{ ORO~(%-(e
this.startIndex = indexes 4{_5z7ody
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[startIndex / pageSize]; w,&RHQB
} N'StT$(
} (~#9KA1A}
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publicint getNextIndex(){ _\6-]
int nextIndex = getStartIndex() + R;%iu0
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pageSize; P-C_sj A7
if(nextIndex >= totalCount) F&Gb[Q&a8
return getStartIndex(); /"U<0jot
else q)/4i9
return nextIndex; Tr8+E;;
} F=#Wfl-o
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publicint getPreviousIndex(){ qr*/}F6
int previousIndex = getStartIndex() - '#fj)
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pageSize; n1ICW 9
if(previousIndex < 0) @'QB rE
return0; 7Vi[I< *
else o7 kGZ
return previousIndex; g!8-yri
} 9}=Fdt
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} lyyi?/W%
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抽象业务类 IpWl;i`__
java代码: o]vd xkU]
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/** >,[(icyzn
* Created on 2005-7-12 <(v!Xj^yO
*/ C$P3&k#W
package com.javaeye.common.business; 8ydOS
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import java.io.Serializable; p(v.sP4w
import java.util.List; QAR<.zXvP
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import org.hibernate.Criteria; MKbW^:
import org.hibernate.HibernateException; \oi=fu=}*
import org.hibernate.Session; *+ 7#z;
import org.hibernate.criterion.DetachedCriteria; <X: 9y
import org.hibernate.criterion.Projections; 7L!k9"X`0F
import <v\|@@X
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org.springframework.orm.hibernate3.HibernateCallback; OlP#|x*
import }}
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org.springframework.orm.hibernate3.support.HibernateDaoS mGIS[_dcs
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upport; xd*kNY
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import com.javaeye.common.util.PaginationSupport; {h2D}F
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public abstract class AbstractManager extends TY?Fs-
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HibernateDaoSupport { g;-CAd5
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privateboolean cacheQueries = false; Agl[Z>Q
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privateString queryCacheRegion; 4FYws5]$
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publicvoid setCacheQueries(boolean ]1klfp,`
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cacheQueries){ ~($h9*\
this.cacheQueries = cacheQueries; 6`4=!ZfI
} j}y"
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publicvoid setQueryCacheRegion(String )#1@@\< ^T
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queryCacheRegion){ pBHr{/\5
this.queryCacheRegion = u|+O%s TQ
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queryCacheRegion; g4Tc (k#
} +YP,LDJ!v
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publicvoid save(finalObject entity){ [~x
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getHibernateTemplate().save(entity); Oq[tgmf
} CYz]tv}g:
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publicvoid persist(finalObject entity){ 3^8%/5$v
getHibernateTemplate().save(entity); CT/`Kg_
} P>:"\I[
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publicvoid update(finalObject entity){ Jcm"i~
getHibernateTemplate().update(entity); 75%!R
} gg933TLu(Q
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publicvoid delete(finalObject entity){ Tc{r}y[)
getHibernateTemplate().delete(entity); }y'KS:Jb
} @zE_fL
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publicObject load(finalClass entity, gVA$P
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finalSerializable id){ {eS!cZJ
return getHibernateTemplate().load oveW )~4
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(entity, id); 8hdd1lVKO8
} Wa
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publicObject get(finalClass entity, H"m^u6Cmy-
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finalSerializable id){ ;l"z4>kt7
return getHibernateTemplate().get 7u0!Q\
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(entity, id); j`(o\Fd )
} Nn+leM
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publicList findAll(finalClass entity){ rT <=`9^{
return getHibernateTemplate().find("from c/b}39X
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" + entity.getName()); ^,@Rd\q
} AS~O*(po
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publicList findByNamedQuery(finalString "|(+~8[
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namedQuery){ |K7JU^"OQ
return getHibernateTemplate <Xv]Ih?@f`
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().findByNamedQuery(namedQuery); `G,\=c~{A
} y~jTI[kS
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publicList findByNamedQuery(finalString query, }m(u oT~
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finalObject parameter){ t\S}eoc
return getHibernateTemplate QXniWJJ
[.;VCk)0x
().findByNamedQuery(query, parameter); S+7>Y? B!
} nTyKZ(#u
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publicList findByNamedQuery(finalString query, yS %J$o&
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finalObject[] parameters){ O$<kWSC
return getHibernateTemplate BNnGtVAbZ
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().findByNamedQuery(query, parameters); S!0<aFh
} ==~X8k|{E
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publicList find(finalString query){ gM '_1zs
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return getHibernateTemplate().find [YLaRr
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(query); 0PjWfM8%
} \GEFhM4)
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publicList find(finalString query, finalObject I5
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parameter){ r1}YN<+,s
return getHibernateTemplate().find W^Wr
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(query, parameter); g kT`C
} cR*D)'/tl
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public PaginationSupport findPageByCriteria X3P~z8_
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(final DetachedCriteria detachedCriteria){ WnyEdYA
return findPageByCriteria [2"a~o\
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); p HXslmrD
} BRLrD/8Le
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public PaginationSupport findPageByCriteria 7jQOwzj
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(final DetachedCriteria detachedCriteria, finalint olB?"M=H
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startIndex){ .y\j .p
return findPageByCriteria HZX(kYV
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(detachedCriteria, PaginationSupport.PAGESIZE, kj{z;5-dl
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startIndex); %}elh79H*
} e$u=>=jV]
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public PaginationSupport findPageByCriteria .B_LQ;0:
jdqVS @SD
(final DetachedCriteria detachedCriteria, finalint JR] /\(
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pageSize, O~?H\2S
finalint startIndex){ _bRd2k,
return(PaginationSupport) DO`
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getHibernateTemplate().execute(new HibernateCallback(){ XHKiz2Pc1
publicObject doInHibernate j")#"& m
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(Session session)throws HibernateException { Wn6~x2 LaV
Criteria criteria = aDceOhfx
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detachedCriteria.getExecutableCriteria(session); |Ii[WfFA|J
int totalCount = Aru=f~!
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((Integer) criteria.setProjection(Projections.rowCount C-O~Oi l
<#/r.}.x
()).uniqueResult()).intValue(); (&t741DN|
criteria.setProjection #;~`+[y?\
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(null); g?&_5)&
List items = 1?%Q"*Y&
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criteria.setFirstResult(startIndex).setMaxResults x8x8T$
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(pageSize).list(); Zq1ZrwPF
PaginationSupport ps = B?n
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new PaginationSupport(items, totalCount, pageSize, v%a)nv
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startIndex); @{/GdB,}
return ps; `s1>7XWf
} @pq2Z^SQ H
}, true); $1lI6 =
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} mWEaUi)Zz
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public List findAllByCriteria(final sT8(f=^)8F
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate oE/g)m%
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().execute(new HibernateCallback(){ 8G3CQ]G
publicObject doInHibernate ]+4QsoFNt
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(Session session)throws HibernateException { 8k~$_AT>u
Criteria criteria = @>:V?
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detachedCriteria.getExecutableCriteria(session); +\Uq=@
return criteria.list(); 4f~ c#0?
} "-
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}, true); WX~:Y,l+u
} ]]Bqte
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public int getCountByCriteria(final OeMI
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DetachedCriteria detachedCriteria){ Lsu_f'p0
Integer count = (Integer) >%6a$r~@
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getHibernateTemplate().execute(new HibernateCallback(){ fG dT2}gd
publicObject doInHibernate mv1g2f+
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(Session session)throws HibernateException { xD.Uh}:J
Criteria criteria = +|0f7RB+R
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detachedCriteria.getExecutableCriteria(session); oyw*Z_ 9~
return a%nksuP3
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criteria.setProjection(Projections.rowCount U~3uu&/r
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()).uniqueResult(); 5z/*/F=X
} ,i]X^z5!
}, true); I}^Q u0ub
return count.intValue(); r ,cz
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} `|uwR5
} ;D8175px;
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用户在web层构造查询条件detachedCriteria,和可选的 mv,p*0
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;15j\{r
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PaginationSupport的实例ps。 "5wer5?
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ps.getItems()得到已分页好的结果集 ob.Br:x
ps.getIndexes()得到分页索引的数组 &0`[R*S
ps.getTotalCount()得到总结果数 7=hISQMsVP
ps.getStartIndex()当前分页索引 gI T3A*x
ps.getNextIndex()下一页索引 6 Mc&gnN
ps.getPreviousIndex()上一页索引 Ot<vn34mt:
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 `*Ju0)g1
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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 8pXului
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一下代码重构了。 wH0m^?a!3
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我把原本我的做法也提供出来供大家讨论吧: [`n)2}
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首先,为了实现分页查询,我封装了一个Page类: kVRh/<s
java代码: Ht,+KbB
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/*Created on 2005-4-14*/ <*Bk.>f!
package org.flyware.util.page; QKHAN{hJ
{t%Jc~p{
/** fbrCl!%P
* @author Joa `b:yW.#w3l
* Z#vU~1W
*/ 7Zw.mM!i
publicclass Page { 2kfX_RK
)` z{T
/** imply if the page has previous page */ ,9.-A-Yw
privateboolean hasPrePage; }7HR<%<7
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/** imply if the page has next page */ P1_ZGeom*
privateboolean hasNextPage; S x0QPX
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/** the number of every page */ 5jey%)=
privateint everyPage; s(0"r.
Hx?OCGj=S*
/** the total page number */ yx\I&\i
privateint totalPage; ^q}cy1"j"
zgn~UC6&
/** the number of current page */ 9Hm>@dBhM
privateint currentPage; .|g|X8X
"8l&m6`U-
/** the begin index of the records by the current b?]Lx.l-
/H'F4->
query */ *=b36M
privateint beginIndex; |aX1PC)o_
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/** The default constructor */ D!WyT`T
public Page(){ CzfGb4
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} + t7n6
?,z/+/:
/** construct the page by everyPage ad#4W0@S
* @param everyPage Oe)B.{;Ph
* */ 0[In5I I
public Page(int everyPage){ 61pJVOe
this.everyPage = everyPage; _Squ%z:D
} b-OniMq~
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/** The whole constructor */ y!u=]BE
public Page(boolean hasPrePage, boolean hasNextPage, *LOUf7`
1+ib(MJ<:#
hM "6-60
int everyPage, int totalPage, 5DS'22GW`
int currentPage, int beginIndex){ htu(R$GSM
this.hasPrePage = hasPrePage; $d\>^Q
this.hasNextPage = hasNextPage; 2H9;4>ss
this.everyPage = everyPage; )WH;G:$&"
this.totalPage = totalPage; *-`-P
this.currentPage = currentPage; UlQS]f~
this.beginIndex = beginIndex; tDQuimYu7
} ]9PQKC2&
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/** sL!+&Id|
* @return ',bSJ4)Y
* Returns the beginIndex. zPc kM)
*/ 2Fc>6]:*
publicint getBeginIndex(){ P}~nL
return beginIndex; f >$V:e([
} )8&;Q9'o
jBMGm"NE
/** 3R&
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* @param beginIndex []l2
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* The beginIndex to set. .C\##
*/ cH48)
publicvoid setBeginIndex(int beginIndex){ $!v:@vNMs
this.beginIndex = beginIndex; 11YpC;[o
} eufGU)M
g:eqB&&
/** ^\Epz*cL
* @return e1/{bX5
* Returns the currentPage. AU4K$hC^
*/ t.pn07$
publicint getCurrentPage(){ yvIzgwN%s!
return currentPage; P$#{a2
} SX]uIkw
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/** ,X}Jpi;/
* @param currentPage b Od<x
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* The currentPage to set. FH)_L1n
*/ >K n7A
publicvoid setCurrentPage(int currentPage){ &>A<{J@VL
this.currentPage = currentPage; i_f\dkol
} !hjA
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/** (sqI:a
* @return e#odr{2#4u
* Returns the everyPage. *!MMl]gU?
*/ 2bu > j1h
publicint getEveryPage(){ Gy F
return everyPage; m[DCA\Mo@
} 9>k_z&<
4l'`q+^-
/** Xv<K>i>k
* @param everyPage |*(R$t X
* The everyPage to set. MqjdW
*/ L%HFsuIO-
publicvoid setEveryPage(int everyPage){ @p<t JR"M
this.everyPage = everyPage; ]sZ!
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} He*c=^8k
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$
/** #HTq\J!
* @return YY4q99^K
* Returns the hasNextPage. -dS@l'$
*/ }D[j6+E
publicboolean getHasNextPage(){ p(!d,YSE
return hasNextPage; Sjp ]TWj
} lWakyCS
{I8C&GS
/** W1_.wN$,5
* @param hasNextPage /|m0)H.>
* The hasNextPage to set. X]}:WGFM
*/ &embAqW:
publicvoid setHasNextPage(boolean hasNextPage){ M(?0c}z
this.hasNextPage = hasNextPage; 4 '5|YGQj
} ha?M[Vyw4Q
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/** iAo/Dnp2J
* @return ]j0/.pG
* Returns the hasPrePage. ]
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*/ =2@V}
publicboolean getHasPrePage(){ tU0jFBB
return hasPrePage; C}qHvwFm
} mXs.@u/
IU;a$
/** \V#fl
* @param hasPrePage Y94S!TbB
* The hasPrePage to set. Z&of-[)
*/ &B\ sG=
publicvoid setHasPrePage(boolean hasPrePage){ 0X:$ASocU
this.hasPrePage = hasPrePage; Y @Ur}
} e}+Zj'5
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/** qTSe_Re
* @return Returns the totalPage. m/3,;P.6
* #$
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*/ sa TS8p z
publicint getTotalPage(){ ^yX >^1
return totalPage; S ,x';"
} HR;I}J 9
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/** 24u_}ZQzY
* @param totalPage _#qfe
* The totalPage to set. ;I?x;lH
*/ l b;P&V
publicvoid setTotalPage(int totalPage){ x\oSD1t,
this.totalPage = totalPage; ;!A=YXB
} Y5c[9\'\
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} 6qSsr]
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C TKeY
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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 U;j\FE^+>
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个PageUtil,负责对Page对象进行构造: XZ@|(_Z
java代码: 'Y.6sB
m(D+!I9
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/*Created on 2005-4-14*/ 1|m%xX,[
package org.flyware.util.page; pp{2[>
m%=*3gH]&
import org.apache.commons.logging.Log; y,/i3^y#_
import org.apache.commons.logging.LogFactory; ]GO=8$Z
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/** bz}-[W+
* @author Joa "8R
&c}
* bObsj]
*/ #qFY`fVf1
publicclass PageUtil { ,OERDWW|6
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privatestaticfinal Log logger = LogFactory.getLog u-_1)'
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(PageUtil.class); H~^)^6)^T
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/** l))Q/8H
* Use the origin page to create a new page ~oJ"si
* @param page =^SxZ Bn
* @param totalRecords \2]_NU5.
* @return \Hdsy="Dnh
*/ Q'qX`K+@`
publicstatic Page createPage(Page page, int AVm+
1
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totalRecords){ a{@}vZx>3
return createPage(page.getEveryPage(), |B^Mj57DO
JHXkQz[Jb
page.getCurrentPage(), totalRecords); On54!m
} 2v2XU\u{t
UOk\fyD2[
/** rOz1tY)l0d
* the basic page utils not including exception 4v`IAR?&K;
.!Pg)|
handler #?V rt,n
* @param everyPage E7M_R/7@y
* @param currentPage >,E^ R `y
* @param totalRecords Nk<^ Qv
* @return page 4"_`Mu_%
*/ aZ+><1TD
publicstatic Page createPage(int everyPage, int 9?8PMh.
b+|3nc!
currentPage, int totalRecords){ 2:_6nWl
everyPage = getEveryPage(everyPage); =#v? }JG
currentPage = getCurrentPage(currentPage); Zazff@O *
int beginIndex = getBeginIndex(everyPage, ^5.XQ0n
dI&Q5M8
currentPage); TL)*onA9
int totalPage = getTotalPage(everyPage, (0B?OkQ
DzQ
totalRecords); l#`G4Vf
boolean hasNextPage = hasNextPage(currentPage, #fYB4.i~
Fs].Fa
totalPage); TN1pg
boolean hasPrePage = hasPrePage(currentPage); N0.|Mb"?t
E5$]0#jB
returnnew Page(hasPrePage, hasNextPage, ?3p7MjvZ
everyPage, totalPage, ;AE-=/<
currentPage, TS#[[^!S
nYFrp)DLK
beginIndex); FY ms]bv
} |K"Q>V2y
ZZ7qSyBs?
privatestaticint getEveryPage(int everyPage){ d&[RfZ`
return everyPage == 0 ? 10 : everyPage; ]%)<9]}
} Qr9;CVW
y TD4![
privatestaticint getCurrentPage(int currentPage){ 6,aH[>W
return currentPage == 0 ? 1 : currentPage; *<\K-NSL
} Xv|=RNz
@phVfP"M
privatestaticint getBeginIndex(int everyPage, int \ l#eW
x
5&V=$]t
currentPage){ ])o{!}QUl\
return(currentPage - 1) * everyPage; %/"n(?$W
} Aeb(b+=
~/]]H;;^u
privatestaticint getTotalPage(int everyPage, int b:D92pH
8.[F3Tk=
totalRecords){ Fq@o_bI
int totalPage = 0; B*,)@h
lI 4tW=
if(totalRecords % everyPage == 0) d<6F'F^w.7
totalPage = totalRecords / everyPage; 1^4:l!0D
else ,VHqZ'6
totalPage = totalRecords / everyPage + 1 ; @kqxN\DE
?9kC[4G
return totalPage; O=A2QykV(
} <;6{R#Tuh
@ M]_],
privatestaticboolean hasPrePage(int currentPage){ "FWx;65CR
return currentPage == 1 ? false : true; ,|{`(y/v
} /{\ /e"5
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privatestaticboolean hasNextPage(int currentPage, WJ25fTsG
0RT 8N=B83
int totalPage){ du66a+@t
return currentPage == totalPage || totalPage == x}yl Rg`[
A^>@6d $2
0 ? false : true; qcS.=Cj?)
} N)H "'#-
4b`E/L}2
<qwf"Ey
} N2v/<
wSN9`"
m$fEk,d
(-21h0N[V
1)56ec<c
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。 sD:o
2(G*
@ph!3<(In,
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 kh5a >OX
#$I@V4O;#
做法如下: WVdV:vJ-
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 .|Huzk+
UqOBr2UmG
的信息,和一个结果集List: ;!MQ@Fi^
java代码: %.Ma_4o
Z
rm8Ys61\=
"lI-/G
/*Created on 2005-6-13*/ 5To@d|{
package com.adt.bo; Y~WdN<g
0O9b
7F
import java.util.List; C#kE{Qw10r
^#HaH
import org.flyware.util.page.Page; 7k(}U_v
!6KX^j-
/** Y%XF64)6
* @author Joa *siX:?l
*/ ~U0%}Bbh
publicclass Result { |O{N_-];.
&-3e3)
private Page page; K(EJ`2]:r
a!9'yc
private List content; b=,BLe\
mn7I# ~
/** R2,9%!iiX
* The default constructor m+<&NDj.
*/ #\0m(v
public Result(){ T/_u;My;
super(); =AIFu\9#a`
} QK]P=pE'C
Vu:ZG*^
/** ;W,* B.~
* The constructor using fields [';o -c"!
* x>yqEdR=o
* @param page x+X@&S
* @param content r#sg5aS7O|
*/ jeu'K vhe
public Result(Page page, List content){ qGk.7wf%
this.page = page; FDMQLx f
this.content = content; Z hfp>D
} Uwc%'=@
Lce,]z\_
/** g\q .
* @return Returns the content. xMJ-=
*/ FA+HR
publicList getContent(){ 6}^x#9\
return content; y2A\7&7
} @t%da^-HS"
-9b=-K.y
/** 1bFZyD"
* @return Returns the page. \p4*Q}t
*/ .]v>LsbhF
public Page getPage(){ dn(!wC]
return page; kR<sSLEb
} f2WVg;Z
aTvyzr1
/** C'JI%HnQ
* @param content _Xf1FzF+a
* The content to set. Y&6jFT_
*/ E{,WpU
public void setContent(List content){ 56Wh<i3
this.content = content;
3f`Uoh+
} 56pj(}eq
G4|C227EO
/** {sw|bLo|+
* @param page 0~nX7
* The page to set. G8repY
*/ 6s@!Yn|?
publicvoid setPage(Page page){ v}DNeIh~
this.page = page; vPnS`&
} MXA?rjd0
} :` SIuu~@
RuHDAJ"&a
zA#pgX[#
b 8@}Jv
i+`8$uz
2. 编写业务逻辑接口,并实现它(UserManager, ,a5q62)q
Ftyxz&-4$p
UserManagerImpl) zZ[kU1Fyv
java代码: `{#""I^_
AF:_&gF
L'wR$
/*Created on 2005-7-15*/ =c6d$
package com.adt.service;
^tTM
7
[Q T ;~5
import net.sf.hibernate.HibernateException; \n}%RD-Ce
\; XJ$~>
import org.flyware.util.page.Page; ~BI`{/O=
94!}
Z>
import com.adt.bo.Result; _N5pxe`
27Gff(
/** |;J`~H"K
* @author Joa -c>3|bo
*/ ndQw>
publicinterface UserManager { PcsYy]Q/
mU[\//
public Result listUser(Page page)throws ^@x&n)nzP
T>'w]wi
HibernateException; <SE-:T]sBz
N1Y
uLG:
} @.L#u#
^C
K!=oO
|21VOPBS
$}4ao2
D?BegF
java代码: r;@0F
=bp'5h8_
/%g@ ;
/*Created on 2005-7-15*/ !~zn*Hm
package com.adt.service.impl; O
C;~ H{
LDegJer-v
import java.util.List; o"qxR'V
O=K0KOj
import net.sf.hibernate.HibernateException; \>\ERVEd
7b~uU@L`
import org.flyware.util.page.Page; m2m
;|rr
import org.flyware.util.page.PageUtil; ,tXI*R
-medD G
import com.adt.bo.Result; $\m:}\%p
import com.adt.dao.UserDAO; h8WM4
PK
import com.adt.exception.ObjectNotFoundException; X!V#:2JY
import com.adt.service.UserManager; GYtgw9 "Y
ea{zL
/** %S%UMA.
* @author Joa V1,p<>9
*/ wtbN@g0
publicclass UserManagerImpl implements UserManager { rrC\4#H[??
"7-}#_!g
private UserDAO userDAO; $mT)<N ;w
/pRv
i>_(:
/** .8'c
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* @param userDAO The userDAO to set. w.rcYywI
*/ #bcZ:D@FC
publicvoid setUserDAO(UserDAO userDAO){ 0[H/>%3O
this.userDAO = userDAO; {*;K>%r\o
} P*[wB_^&UP
E;H9]*x/
/* (non-Javadoc) n3?
msY(*
* @see com.adt.service.UserManager#listUser uju'Bs7
SDbkPx
(org.flyware.util.page.Page) me@`;Q3
*/ SP<(24zdd
public Result listUser(Page page)throws IPTFx
)]G
`#ff`j|a
HibernateException, ObjectNotFoundException { jBEW("4R
int totalRecords = userDAO.getUserCount(); aQHR=.S]X
if(totalRecords == 0) ;eo}/-a_Xw
throw new ObjectNotFoundException ^$`mS&3/q
;[4=?GL*
("userNotExist"); Fsl="RB7f
page = PageUtil.createPage(page, totalRecords); O=LW[h!
List users = userDAO.getUserByPage(page); ~p'|A}9[/
returnnew Result(page, users); 'PrBa[%
} K20Hh7cVJ
u-jV@Tz
} -F(luRBS(W
K#6@sas
UFZOu%Y
HP7~Zn)c
0`V=x+*,
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 0i5S=L`j
$U/lm;{%
询,接下来编写UserDAO的代码: *"OlO}o
3. UserDAO 和 UserDAOImpl: *N: $,xf
java代码: :^paI
qHheF%[\5
P
B-x_D
/*Created on 2005-7-15*/ ?c8(<_I+
package com.adt.dao; Wm{ebx
\FX"A#
import java.util.List; \
C$t
Ttl
m&d+C
import org.flyware.util.page.Page; }Z\S__\9
*qYw
import net.sf.hibernate.HibernateException; )n<p_vz
"\vQVZd-E
/** *Ej;}KSv
* @author Joa 0nBDF79
*/ b)#rUI|O
publicinterface UserDAO extends BaseDAO { g9;s3qXiG
`gCJ[
publicList getUserByName(String name)throws `t9k!y!GV
g[O
HibernateException; #l`\'0`.
30SQ&j[N]
publicint getUserCount()throws HibernateException; ~K5A$s2
MSBrI3MqQ
publicList getUserByPage(Page page)throws mJ(ElDG
7;Lv_Y"b
HibernateException; pUqNB_
g'w"U9tjO
} "1XTgCu\
)/[L)-~y~
XM"Qs.E
Yv)c\hm(7j
m6^#pqSL
java代码: _OJfd
gm-9 oA
X
X!ldL|Ua%
/*Created on 2005-7-15*/ )}"`$6:k`
package com.adt.dao.impl; \b6{u6?+
~z]VDEJ{q
import java.util.List; KJS-{ed
gMZ+kP`
import org.flyware.util.page.Page; _NwHT`O[
br TP}A
import net.sf.hibernate.HibernateException; #*w)rGkU2
import net.sf.hibernate.Query; Ahbh,U
{98e_z w
import com.adt.dao.UserDAO; O0
Uh
k'
Fu&r
/** 0s{7=Ef
* @author Joa u>vvW|OB[
*/ j+3rS
public class UserDAOImpl extends BaseDAOHibernateImpl ?WqaT) l~
:x5O1Zn/t
implements UserDAO { ]9_}S
dHg[r|xC
/* (non-Javadoc) Pw +nO
* @see com.adt.dao.UserDAO#getUserByName ? EHheZ{
SYf1dbc..u
(java.lang.String) 3` oOoKX
*/ >!lpI5'Z&
publicList getUserByName(String name)throws E`@Z9k1 `
3OKs?i3A
HibernateException { ]jiVe_ OS<
String querySentence = "FROM user in class Zo^]y'
'/X]96Ci7
com.adt.po.User WHERE user.name=:name"; !J!&JQ|
Query query = getSession().createQuery _emW#*V
$%'3w~h`
(querySentence); vGPsjxk&
query.setParameter("name", name); #639N9a~
return query.list(); dS <*DP
} d+5~^\lV
{,*vMQ<^
/* (non-Javadoc) 3iX\):4
* @see com.adt.dao.UserDAO#getUserCount() l1O"hd'~s
*/ uM,Ps}
publicint getUserCount()throws HibernateException { E,K>V:P*
int count = 0; gX-hYQrC
String querySentence = "SELECT count(*) FROM P,3w
b
b5
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user in class com.adt.po.User"; HOCj* O4
Query query = getSession().createQuery L@zhbWY
E]m?R 4
(querySentence); Q[q`)~|
count = ((Integer)query.iterate().next T*=*$%
U1lqg?KO
()).intValue(); h9}*_qc&kV
return count; mW{>
} W\w#}kY
,p(&G_
/* (non-Javadoc) Ks6\lpr
* @see com.adt.dao.UserDAO#getUserByPage /Yg&:@L
S ++~w9}
(org.flyware.util.page.Page) Yc_(g0NK
*/ H=f|X<8
publicList getUserByPage(Page page)throws )i[Vq|n
-TG ="U
HibernateException { eMFxdtH
String querySentence = "FROM user in class Q@NFfJJ
W-&V:S{<
com.adt.po.User"; v Q[{<|K
Query query = getSession().createQuery n{d}]V@
T#6'] D
(querySentence); 2!\y0*}K
query.setFirstResult(page.getBeginIndex()) [6K2V:6:
.setMaxResults(page.getEveryPage()); *_`T*$
return query.list(); v:B_%-GfOA
} Wg[?i C*~
g9}u6q
} Y'i0=w6G
7Ro7/PT(
DBAJkBs
aO.'(kk8
;!, ]}2w*X
至此,一个完整的分页程序完成。前台的只需要调用 OHssUt
C, n]9
userManager.listUser(page)即可得到一个Page对象和结果集对象 ogs9obbZ!
Jc~^32
的综合体,而传入的参数page对象则可以由前台传入,如果用 yiQke
kMKI=>s+
webwork,甚至可以直接在配置文件中指定。 GC66n1- X
\hdR&f5q
下面给出一个webwork调用示例: o m`r^3,
java代码: P{)H7B>
:{h,0w'd
$ ;>,
/*Created on 2005-6-17*/ J9)wt ?%j
package com.adt.action.user; vY *p][$
r=n|MT^O
import java.util.List; ?)<zrE5p
S+ymdZ)xZ`
import org.apache.commons.logging.Log; HB{-^9{E
import org.apache.commons.logging.LogFactory; +'>N]|Z
import org.flyware.util.page.Page; _Ta9rDSP]
[?RLvhU|
import com.adt.bo.Result; TSdjX]Kf
import com.adt.service.UserService; DX}EOxO,.
import com.opensymphony.xwork.Action; w4'(Y,(`
PtO-%I<N
/** G\Hck=P[$3
* @author Joa #I%< 1c%XA
*/ `=uCp^+v
publicclass ListUser implementsAction{ j:"+/5rV8
}!0,(<EsV
privatestaticfinal Log logger = LogFactory.getLog nf,>l0,,'
yZHQql%J
O
(ListUser.class); aBr%"&Z.MG
, Ot3N\%yn
private UserService userService; H`-%)c=
BT
98WR"\
private Page page; t"2WJ-1k}
bVtboHlY
privateList users; TcZ
Ci^1F
1KruGq~
/* ?XsL4HIx
* (non-Javadoc) Z{chAg\
* 0vS%m/Zi-
* @see com.opensymphony.xwork.Action#execute() [aO"9
*/ |?s%8c'w=
publicString execute()throwsException{ *{Wh-bc
Result result = userService.listUser(page); J4j?rLR3p
page = result.getPage(); [Qy]henK
users = result.getContent(); *Zt)J8C
return SUCCESS; ;PaB5TT(
} TmKO/N@}
BS*cG>T
/** #Vv*2Mc
* @return Returns the page. o1Mb HBb
*/ ?Y
)Qy,
public Page getPage(){ @MtF^y
return page; uWx/V+w
} PHfGl
IL3,dad'^
/** 5ez"B]&T
* @return Returns the users. 5zpk6FR$
*/ mt fDl;/D
publicList getUsers(){ H\8i9RI
return users; (oq(-Wv
} @WhcY*R2
m %ET!+
/** 3tnYK&
* @param page bT[Q:#GL
* The page to set. @)<uQ S
*/ %E1~I\n:F
publicvoid setPage(Page page){ ?j8CkqX!
this.page = page; wIxLr{
} K_]LK
rM [Ps=5
/** *Ei~2O}
* @param users Yr-,0${m
* The users to set. k49CS*I
*/ X%`8h_
publicvoid setUsers(List users){ s<:"rw`
this.users = users; 70HEu@-
} }xLwv=Ia
*}ay
/** "^_p>C)T
* @param userService ^%go\ C ;
* The userService to set. ed{z^!w4
*/ }5Y.N7F
publicvoid setUserService(UserService userService){ &`@,mUi{Ac
this.userService = userService; !!2~lG<]
} Ug_zyfr
} `~@BU
LE1&atq
Pl1:d{"d
jY: )W*TXt
rt5FecX\
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, $ NNd4d*
:K-05$K
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 V5]}b[X
`,-w+3?Al
么只需要: ]VuB2L[D
java代码: %Y0,ww2
HNFG:t9
YU*u!
<?xml version="1.0"?> QL_vWG-
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork xEULV4Qw
gL)l)}#
1.0//EN" "http://www.opensymphony.com/xwork/xwork- MM+x}g.?
](^$5Am
1.0.dtd"> H%`$@U>
1R}rL#h;=
<xwork> G=1&:nW'
>M2~BDZ
<package name="user" extends="webwork- 7yUtG^'b
%MA o<,ha
interceptors"> 5X4 #T&.
df85g
<!-- The default interceptor stack name 8[PD`*w
3e)W_P*0?
--> t[dOWgHi
<default-interceptor-ref "L?h@8sa
o7_*#5rD
name="myDefaultWebStack"/> .dbZ;`s
%S'gDCwq
<action name="listUser" 0.MD_s0)>
IjshxNk
class="com.adt.action.user.ListUser"> /b|V=j}W
<param :NHP,"
pm)kocG
name="page.everyPage">10</param> Wqy\yS [
<result C[4{\3\Va
SC Qr/Q
name="success">/user/user_list.jsp</result> [osIQ!u;:
</action> X-lB1uq^
e1Ne{zg~
</package> xJ&E2Bf
RWX?B
</xwork> 3Ygt!
%ZKP d8
?QJS6i'k
hggP9I:s,
zp4aiMn1F
q=,
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 ,$H[DX
;?q>F3n
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。 .eNeqC
pW
y+oZ
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 tz6N,4J?
t)p . $
\f!j9O9S
006qj.
x>ZnQ6x~m]
我写的一个用于分页的类,用了泛型了,hoho (=jztIZC
?"+g6II
java代码: cZb5h 9
>.xgo6
$;J:kd;<
package com.intokr.util; '5f6
M^}|2
7o99@K,
import java.util.List; :l;SG=scx
w3<%wN>tE
/** 8:9/RL\"x
* 用于分页的类<br> 1ZrJ7a7=
* 可以用于传递查询的结果也可以用于传送查询的参数<br> #M)SAe2
* 9%^IMUWA
* @version 0.01 ji&%'h
* @author cheng ~;QzV?%
*/ (m~gG|n4
public class Paginator<E> { lihV! 1
privateint count = 0; // 总记录数 fPpFAO
privateint p = 1; // 页编号 E! s?amM4
privateint num = 20; // 每页的记录数 R(1N]>
privateList<E> results = null; // 结果 rL KwuZ
*LZB.84
/** FD1Z}v!5IJ
* 结果总数 =O.%)|
*/ H\PY\O&cP
publicint getCount(){ pm4'2B|)g
return count; F7"v}K]X
} 9kO}054
vl"{ovoC
publicvoid setCount(int count){ ([#4H3uO-
this.count = count; p]]*H2UD
} A8zh27[w%
/[FES78p
/** myvn@OsEw
* 本结果所在的页码,从1开始 32S5Ai@Cd"
* &*\-4)Tf
* @return Returns the pageNo. 'CfM'f3uu
*/ `pJWZ:3
publicint getP(){ B/^1uPTZ71
return p; wBJP8wES=
} c]x'}Kc
L7rEMq
/** CKuf'h#
* if(p<=0) p=1 FSNzBN
* >hFg,5 _l3
* @param p tsWzM9Yf
*/ 0]u=GD%
publicvoid setP(int p){ cS98%@DR
if(p <= 0) G[YbgG=9Y
p = 1; 1;p'2-x
this.p = p; 0u4:=Z}W
} mAk@Q|u
.1u"16_
/** <;d?E%`
* 每页记录数量 93|u.
@lEy
*/ ; 4E0%@R
publicint getNum(){ 1.]Py" @:
return num; $/%|0tQ
} jUq^$+N
/@5X0m
/** #c5 NFU}9
* if(num<1) num=1 C3af>L@}
*/ =GpO}t">
publicvoid setNum(int num){ Y`QJcC(3
if(num < 1) A L#"j62
num = 1; <_@ S@t)
this.num = num; FAVw80?5k
} Ed3 *fY
%,rUN+vW
/** t)74(
* 获得总页数 X I\zEXO
*/ YCwfrz
publicint getPageNum(){ *yqEl
O
return(count - 1) / num + 1; [X.sCl|
} DfFsCTu
L&F0^
/** -I.OvzQ*
* 获得本页的开始编号,为 (p-1)*num+1 #/ 1
*/ 5taYm'
publicint getStart(){ pHlw&8(f"
return(p - 1) * num + 1; Nhv~f0
} !Y3w]_x[:
J7BfH,o
/** ~S)o('
* @return Returns the results. B*A{@)_
*/ 0+b1R}!2
publicList<E> getResults(){ C8%Io l
return results; 83UIH0(
} Exox&T
'vT
XR_D
public void setResults(List<E> results){ &ZgB b
this.results = results; 2{zFO3i<3
} PNLtpixZ
~/J:p5?L
public String toString(){ Mg]q^T.a
StringBuilder buff = new StringBuilder S(jbPQT
'G3B02*
(); )/h~csy:~
buff.append("{"); $D8eCjUm
buff.append("count:").append(count); \D] N*
buff.append(",p:").append(p); *p{wC
r
buff.append(",nump:").append(num); 8Letpygm
buff.append(",results:").append WRQJ6B
Vd[[<
(results); r{.DRbn
buff.append("}"); Wa%Zt*7
return buff.toString(); "gXz{$q
} /i|T \
R_ojK&%
} b>AFhj :
&Ib8xwb:
yzt6