Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 msoE8YK&tg
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 yr;oq(&N
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 +pjD{S~Y
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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 ,%ajIs"Gi
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分页支持类: Bq$bxuhV
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java代码: OK2wxf
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package com.javaeye.common.util; a{u)~:/G
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import java.util.List; DsFrA]
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publicclass PaginationSupport { mY%PG
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publicfinalstaticint PAGESIZE = 30; 8\ :T*u3
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privateint pageSize = PAGESIZE; Y}Qu-fm
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privateList items; 7v\OS-
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privateint totalCount; *?i~AXJm
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privateint[] indexes = newint[0]; n$~RgCf
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privateint startIndex = 0; 3[ Z? `X
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public PaginationSupport(List items, int -EL"Sv?
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totalCount){ pWQ?pTh
setPageSize(PAGESIZE); q=6M3OnS>
setTotalCount(totalCount); G-;pMFP(?
setItems(items); s=KA(4p
setStartIndex(0); ,Ma$:6`f
} 61wGIN2,
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public PaginationSupport(List items, int jNB-FVaT
,D#~%kq~
totalCount, int startIndex){ t(s']r
setPageSize(PAGESIZE); 5$9j&&R
setTotalCount(totalCount); rgOB0[
setItems(items); 2p'qp/
setStartIndex(startIndex); <K2 )v~
} :KW
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public PaginationSupport(List items, int `VS/Xyp
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totalCount, int pageSize, int startIndex){ 7j@TW%FmV\
setPageSize(pageSize); ThFI=K
setTotalCount(totalCount); R2r0'Yx
setItems(items); q`qbaX\J3
setStartIndex(startIndex); |~uCLf>
} &}*[-z
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publicList getItems(){ ! WQEv_G@
return items; /oh[Nu1D
} EpPKo
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publicvoid setItems(List items){ =o9
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this.items = items; jgukW7H
} 1k;X*r#
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publicint getPageSize(){ k2O==IG]6
return pageSize; h( Iti&
} ZfIQ Fh>
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publicvoid setPageSize(int pageSize){ j1>1vD-`T
this.pageSize = pageSize; T}U`?s`)
} ?HU(0Vgn'
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publicint getTotalCount(){ UXe @c@3
return totalCount; :5p`H
} W${0#qq
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publicvoid setTotalCount(int totalCount){ S{&;
if(totalCount > 0){ _W&.{
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this.totalCount = totalCount; 7eZ,;
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int count = totalCount / I)n%aT fo8
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pageSize; lKwI lp
if(totalCount % pageSize > 0) 3M/kfy
count++; $S3C_..
indexes = newint[count]; _AK-AY
for(int i = 0; i < count; i++){ ofRe4
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indexes = pageSize * UDGVq S!,E
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} 02?y%
}else{ &@nI(PXv
this.totalCount = 0; n{=vP`V_
} ~#OnA1)
} <Y<%=`
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publicint[] getIndexes(){ | [P!9e
return indexes; C+jlIT+
} N9idk}T
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publicvoid setIndexes(int[] indexes){ "){"{~
this.indexes = indexes; P;][i| x
} T[q2quXgk
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publicint getStartIndex(){ `BF +)fs
return startIndex; ~xkcQ{
} FAo\`x
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publicvoid setStartIndex(int startIndex){ g2BE-0, R
if(totalCount <= 0) }cEcoi<v!
this.startIndex = 0; 9K~X}]u
elseif(startIndex >= totalCount) PA&Ev0`+
this.startIndex = indexes 1H{JT
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[indexes.length - 1]; G[ @RZ~o4
elseif(startIndex < 0) <V>]-bl/
this.startIndex = 0; 4Zo.c*
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else{ Wv8?G~>
this.startIndex = indexes KZ>cfv-&a
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[startIndex / pageSize]; RGf&KV/
} RG0kOw0
} -LhO
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publicint getNextIndex(){ ACc tyGd
int nextIndex = getStartIndex() + eD4X:^@
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pageSize; 58V`I5_
if(nextIndex >= totalCount) <Y:{>=
return getStartIndex(); Nu/wjx$b
else e
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return nextIndex; +Hgil
} f; w\k7 #
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publicint getPreviousIndex(){ =;ClOy9
int previousIndex = getStartIndex() - <Z5-?wgf9
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pageSize; e#!%:M;4P
if(previousIndex < 0) qILb>#
return0; 2RG6m=Y8y
else [MhKR }a
return previousIndex; +saXN6
} ]l>LU2 sx
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} {bHUZen
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抽象业务类 WX6}@mS.
java代码: %;_94!(hC
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/** 2. '` mGu
* Created on 2005-7-12 0xVw{k}1U
*/ & OYo
package com.javaeye.common.business; x<5ARK6\=
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import java.io.Serializable; /9ctmW1!<
import java.util.List; U}@xMt8@l
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import org.hibernate.Criteria; v|\3FEu@
import org.hibernate.HibernateException; `>)[UG!:|
import org.hibernate.Session; 2Pow-o*r
import org.hibernate.criterion.DetachedCriteria; )G#mC0?PV
import org.hibernate.criterion.Projections; ];xDXQd
import qYoB;gp
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org.springframework.orm.hibernate3.HibernateCallback; bd]9kRq1K
import 4>A|2+K\
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org.springframework.orm.hibernate3.support.HibernateDaoS @<NuuYQ&
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upport; y+3+iT@i
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import com.javaeye.common.util.PaginationSupport; v5>A1\
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public abstract class AbstractManager extends e, N}z
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HibernateDaoSupport { WP2=1"X63
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privateboolean cacheQueries = false; 8Cs;.>75[
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privateString queryCacheRegion; G %'xEr0n
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publicvoid setCacheQueries(boolean m _cRK}>
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cacheQueries){ +F-EgF+J
this.cacheQueries = cacheQueries; b7XB l
} m9vX8;.
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publicvoid setQueryCacheRegion(String ^M{,{bG
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queryCacheRegion){ y];-D>jk
this.queryCacheRegion = z',Fa4@z
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queryCacheRegion; [\AOr`7
} K+pVRDRcs
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publicvoid save(finalObject entity){ Xu8I8nAwl
getHibernateTemplate().save(entity); 6<2H 7'
} 9 w$m\nV
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publicvoid persist(finalObject entity){ *,mI=1
getHibernateTemplate().save(entity); <+k"3r{y"
} |>yWkq
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publicvoid update(finalObject entity){ J$Z=`=]t+
getHibernateTemplate().update(entity); 2]1u0-M5L
} }x?F53I)
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publicvoid delete(finalObject entity){ 4vEP\E3u<j
getHibernateTemplate().delete(entity); CHsg2S
} l|=4FIMD
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publicObject load(finalClass entity, zw['hqW
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finalSerializable id){ xNzGp5H
return getHibernateTemplate().load ];Z6=9n
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(entity, id); GL=}Vu`(*
} /M_$4O;*@
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publicObject get(finalClass entity, MC* Hl`C
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finalSerializable id){ ZUHRATT-
return getHibernateTemplate().get 7~SwNt,
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(entity, id); z$e6T&u5B
} 6Q^~O*cw
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publicList findAll(finalClass entity){ =j62tDS
return getHibernateTemplate().find("from DMM<,1
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" + entity.getName()); X*QS/\
} P.}d@qD{)
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publicList findByNamedQuery(finalString xSm;~')g
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namedQuery){ h q)1YO
return getHibernateTemplate 'v"=
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().findByNamedQuery(namedQuery); $@D a|d4
} g1s%x=7/
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publicList findByNamedQuery(finalString query, pFv u,Q"
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finalObject parameter){ $VuXr=f}
return getHibernateTemplate ){*+s RBW
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().findByNamedQuery(query, parameter); 5&ku]l+
} K]hp-QK<
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publicList findByNamedQuery(finalString query, )th[fUC(
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finalObject[] parameters){ J;C:nE|V
return getHibernateTemplate uh)S;3|
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().findByNamedQuery(query, parameters); w G %W{T$
} c+ oi8G
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publicList find(finalString query){ /|IPBU 5
return getHibernateTemplate().find k, HC"?K
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(query); U ? +_\
} x4oWZEd
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publicList find(finalString query, finalObject cCe~OlXQ
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parameter){ >]\I:T
return getHibernateTemplate().find c.ow4~>
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(query, parameter); Z0F~?
} _)M,p@!?=h
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public PaginationSupport findPageByCriteria 23s;O))
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(final DetachedCriteria detachedCriteria){ qqrjI.
return findPageByCriteria CD$#}Id
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); #Wk=y?sn
} e-nA>v
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public PaginationSupport findPageByCriteria -8Jw_
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(final DetachedCriteria detachedCriteria, finalint Zw.8B0W
7>FXsUt_
startIndex){ tyu@aCK
return findPageByCriteria 9R50,lsE
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(detachedCriteria, PaginationSupport.PAGESIZE, :DD<0
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startIndex); \N,ox(f?gW
} 9)Fx;GxL
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public PaginationSupport findPageByCriteria Nep4J;
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(final DetachedCriteria detachedCriteria, finalint |$RNY``J
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pageSize, f"ZlJV a
finalint startIndex){ $x0SWJ \G
return(PaginationSupport) IH]9%d)
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getHibernateTemplate().execute(new HibernateCallback(){ <ql,@*Y
publicObject doInHibernate kT%wt1T4
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(Session session)throws HibernateException { '![oLy
Criteria criteria = *g/klK
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detachedCriteria.getExecutableCriteria(session); YW7W6mWspS
int totalCount = ,>GHR{7>(
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((Integer) criteria.setProjection(Projections.rowCount J:xGEa t
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()).uniqueResult()).intValue(); Nwvlv{k'
criteria.setProjection /^.|m3
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(null); aurs~
List items = vgz`+Zj*S
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criteria.setFirstResult(startIndex).setMaxResults d2rs+-
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(pageSize).list(); OQVrg2A%(
PaginationSupport ps = IhnBp 6p9
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new PaginationSupport(items, totalCount, pageSize, ~>2uRjvkwB
}^
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startIndex); &m5zd$6
return ps; .E4*>@M5
} E5k)~P`|
}, true); z _!ut
} TdtV (
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public List findAllByCriteria(final 18X@0e
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DetachedCriteria detachedCriteria){ Syk)S<
return(List) getHibernateTemplate \Wbmmd}8
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().execute(new HibernateCallback(){ FFHq':v
publicObject doInHibernate nxLuzf4U5
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(Session session)throws HibernateException { D /eH~
Criteria criteria = Sj9fq*
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detachedCriteria.getExecutableCriteria(session); )vp0X\3q`
return criteria.list();
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} yI0bSu<j-
}, true); 55[ 4)*
} t@q'm.:uw<
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public int getCountByCriteria(final Q8p6n
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DetachedCriteria detachedCriteria){ |)-kUu
Integer count = (Integer) j8Z, :op
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getHibernateTemplate().execute(new HibernateCallback(){ 91-bz^=xO
publicObject doInHibernate |P|B"I<?
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(Session session)throws HibernateException { L@}PW)#
Criteria criteria = 'ofj1%c
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detachedCriteria.getExecutableCriteria(session); U|^xr~q!f-
return $=aO*i
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criteria.setProjection(Projections.rowCount 5&]5*;Bv J
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()).uniqueResult(); =ily=j"hK
} 20:F$d
}, true); Lvk}% ,S8t
return count.intValue(); .sMs_ 5D
} s**<=M GK
} 36d nS>4
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用户在web层构造查询条件detachedCriteria,和可选的 tvkdNMyX%9
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 h`[$
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PaginationSupport的实例ps。 L/3A g*
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ps.getItems()得到已分页好的结果集 )6|L]'dsZ
ps.getIndexes()得到分页索引的数组 qi-XNB`b
ps.getTotalCount()得到总结果数 "oP^2|${
ps.getStartIndex()当前分页索引 z;OYPGvkw
ps.getNextIndex()下一页索引 Rr) 5[
ps.getPreviousIndex()上一页索引 +WX/4_STV
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 xtV+Le%
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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 ]#/nn),Z
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一下代码重构了。 W4^L_p>Tm^
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我把原本我的做法也提供出来供大家讨论吧: kY0HP a
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首先,为了实现分页查询,我封装了一个Page类: [W[{
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java代码: 3JazQU
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/*Created on 2005-4-14*/ Sp`l>BL
package org.flyware.util.page; FO{=^I5YA
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/** hmy%X`%j
* @author Joa F^!D[:;jK
* dFg>uo
*/
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publicclass Page {
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/** imply if the page has previous page */ _]:b@gXUw
privateboolean hasPrePage; *k?:k78L
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/** imply if the page has next page */ R2bq hSlF
privateboolean hasNextPage; _&KqmQ8$7
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/** the number of every page */ =H95?\}T[
privateint everyPage; WtSs:D
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/** the total page number */ r>mBe;[TX
privateint totalPage; b?wrOS
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/** the number of current page */ b,!C8rJ
privateint currentPage; 1{uxpYAP=
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/** the begin index of the records by the current n ]%2Kx
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query */ |x[I!I7.F
privateint beginIndex; a@}.96lStD
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/** The default constructor */ @N'n>8Wn
public Page(){ r&=ulg
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} ct+F\:e
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/** construct the page by everyPage q~{)
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* @param everyPage %G?@Hye3
* */ *)^6'4=
public Page(int everyPage){
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this.everyPage = everyPage; 4P{|H
} srS!X$cec
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/** The whole constructor */ +IZ=E
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public Page(boolean hasPrePage, boolean hasNextPage, VZ]iep
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int everyPage, int totalPage, Y;w|Fvjj+
int currentPage, int beginIndex){ 44CZl{pt
this.hasPrePage = hasPrePage; ss^a=?~
this.hasNextPage = hasNextPage; RhYe=Qh4{p
this.everyPage = everyPage; k@xinK%O{
this.totalPage = totalPage; EKc<|e,F
this.currentPage = currentPage; _|~Dj)z
this.beginIndex = beginIndex; =<\22d5L
} 'h$:~C
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/** @52#ZWy
* @return w4
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* Returns the beginIndex. FgdnX2s J
*/ cXXZ'y>FP
publicint getBeginIndex(){ *F$@!ByV
return beginIndex; )x-b+SC
} s,R:D).
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/** \((MoQ9Qk
* @param beginIndex (Y py}
* The beginIndex to set. jUT`V
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*/ py6<QoGV
publicvoid setBeginIndex(int beginIndex){ a)|y0w)vV
this.beginIndex = beginIndex; L:
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} ?mMM{{%(.
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/** We6eAP /Z
* @return [^!SkQ
* Returns the currentPage. :.PA(97xb
*/ `IN!#b+Eo
publicint getCurrentPage(){ ?K$&|w%{3
return currentPage; k?=1q[RQH
} bH+NRNI]
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/** B*/!s7 c.
* @param currentPage wv~:^v'
* The currentPage to set. @Y0ZW't
*/ 9nY`rF8@
publicvoid setCurrentPage(int currentPage){ \?
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this.currentPage = currentPage; t
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} @9^OHRZX
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/** ?NBae\6r
* @return ]m_x;5s $
* Returns the everyPage. %oBP6|e
*/ MlTC?Rp#
publicint getEveryPage(){ "DN,1Q
lCp
return everyPage; 0 u*a=f=
} )\])?q61
j_C"O,WS
/** (wj:Gc
* @param everyPage ?}`-?JB1
* The everyPage to set. AojL4H|
*/ y\v#qFVOZ
publicvoid setEveryPage(int everyPage){ ~\=D@G,9
this.everyPage = everyPage; l8~(bq1
} izSX
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/** Z/,R{Jgt"
* @return xLed];2G
* Returns the hasNextPage. %P}H3;2
*/ P!-RZEt$
publicboolean getHasNextPage(){ b5MBzFw
return hasNextPage; iM!Ya!
} b}TvQ+W]2
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/** 3$hIc)
* @param hasNextPage s.4+5rE
* The hasNextPage to set. 5mamWPw
*/ L#SW!
publicvoid setHasNextPage(boolean hasNextPage){ #ss/mvc3
this.hasNextPage = hasNextPage; ?|,:;^2l1
} H+*3e&
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/** /mwUDf 6x
* @return b |:Y3_>
* Returns the hasPrePage. "{8j!+]4i
*/ *I :c@iCNJ
publicboolean getHasPrePage(){ pZ8J\4+
return hasPrePage; G:*vV#K
} rp\`uj*D
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/** +iQ@J+k
* @param hasPrePage k, N{
* The hasPrePage to set. g$]WKy(D
*/ t]I9[5Pq\
publicvoid setHasPrePage(boolean hasPrePage){ af<h2r
this.hasPrePage = hasPrePage; np2&W'C/i
} N]FRL\K
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/**
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* @return Returns the totalPage. WVD48}HF-
* t
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*/ )W= O~g
publicint getTotalPage(){ Q u2
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return totalPage; NsI. mTc2
} D\M"bf>q1
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/** gcnX^[`S
* @param totalPage * WV=X p
* The totalPage to set. .xqi7vVHZ
*/ NCh-BinK@
publicvoid setTotalPage(int totalPage){ PVg<Ovi^d
this.totalPage = totalPage; ' pgPQM<
} ZBDF>u@
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} rf H1Zl
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umns*U%T;
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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 2.WI".&y=
QM8Ic,QFvo
个PageUtil,负责对Page对象进行构造: R*vQvO%)h
java代码: PR5N:Bw
| Uics:cQC
eP"B3Jw
/*Created on 2005-4-14*/
@_f^AQ
package org.flyware.util.page; 8#;=>m%
@<eKk.Y?+
import org.apache.commons.logging.Log; /-v ;
import org.apache.commons.logging.LogFactory; G@/iK/>5|`
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/** fV4rVy8
* @author Joa z'l
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* ~;9n6U
*/ {@CQ
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publicclass PageUtil { -+{[.U<1jk
uGz)Vz&3
privatestaticfinal Log logger = LogFactory.getLog 4GP?t4][
|dQz(z&6{5
(PageUtil.class); V?dwTc
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/** ATqblU>D
* Use the origin page to create a new page O|sk"YXF
* @param page y5F+~z}{
* @param totalRecords KANR=G
* @return hlL$3.]
*/ 2$Xof
publicstatic Page createPage(Page page, int ,r*Kxy
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totalRecords){ vYm-$KQ"o
return createPage(page.getEveryPage(), Ea
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page.getCurrentPage(), totalRecords); 8!|vp7/
} C W#:'
YIwa = ^
/** 0?$|F0U"J
* the basic page utils not including exception CIMI?
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8~
handler vD@|]@gq
* @param everyPage 4/~x+tdc
* @param currentPage Jy/<
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* @param totalRecords i#>t<g`l
* @return page ^85Eveu
*/ Awa| (]
publicstatic Page createPage(int everyPage, int nBp6uNK[
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currentPage, int totalRecords){ /%g9g_rt#
everyPage = getEveryPage(everyPage); \_O#M
currentPage = getCurrentPage(currentPage); 5H.~pc2y
int beginIndex = getBeginIndex(everyPage, hy~[7:/<I&
xh:I]('R
currentPage); R/x3+_.f
int totalPage = getTotalPage(everyPage, !b_(|~7Lc
{Vj&i.2,
totalRecords); OGg\VV'
boolean hasNextPage = hasNextPage(currentPage, F/ZFO5C%
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totalPage); V K6D
boolean hasPrePage = hasPrePage(currentPage); we[+6Z6J
0F-{YQr>
returnnew Page(hasPrePage, hasNextPage, =s":Mx,o
everyPage, totalPage, peu9Bgs
currentPage, />mK.FT
"'bl)^+?,
beginIndex); i<F7/p "-
} eMnK@J
mP\V.^
privatestaticint getEveryPage(int everyPage){ .F8[;+
return everyPage == 0 ? 10 : everyPage; vY_[@y
} `2]0 X#R
V3ht:>c9qs
privatestaticint getCurrentPage(int currentPage){ 1v|-+p42
return currentPage == 0 ? 1 : currentPage; VA[EY`8
} )KE
&*>.u8:r
privatestaticint getBeginIndex(int everyPage, int ^O*-|ecA
tnobqL'
currentPage){ :pdX
return(currentPage - 1) * everyPage; V5(_7b#z``
} aGC3&c[Wx
rs?Dn6:;B
privatestaticint getTotalPage(int everyPage, int JrOxnxd^
j yD3Sa3
totalRecords){ z.8 nYL5^}
int totalPage = 0; WGn=3(4
.f J8
if(totalRecords % everyPage == 0) N-QS/*C.~
totalPage = totalRecords / everyPage; 7tlK'j'
else k5E2{&wZ
totalPage = totalRecords / everyPage + 1 ; 3bWGWI
cZ_)'0
return totalPage; 7ivo Q
} ^%,{R},s
H9)n<r
privatestaticboolean hasPrePage(int currentPage){ rb-ao\
return currentPage == 1 ? false : true; y#B=9Ri=z
} ,:PMS8pS
@
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privatestaticboolean hasNextPage(int currentPage, A]!0Z:{h%
9oJM?&i
int totalPage){ <b
H*f w
return currentPage == totalPage || totalPage == nC p/.]Y*
'Wnh1|z
0 ? false : true; $6mShp9(
} *@' 'OyL
r\Y,*e
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} @$r[$D
v
**%&|9He
N_NN0
? Vd~
eR \duZ!`
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 BS fmS(.
u!|_bI3
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ,Suk_aX>
syBpF:`-W
做法如下: Lbrl CB+
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7he,(V
56z>/`=
的信息,和一个结果集List: 7JBs7LG
java代码: AuQ|CXG-\
4Y?2u
R 9`[C
/*Created on 2005-6-13*/ zN!W_2W*
package com.adt.bo; [@lK[7 u
6:G&x<{
import java.util.List; GKIzU^f
n7bVL#Sq[
import org.flyware.util.page.Page; 76rv$z{g^
(.P}>$M9
/** `f}s<At
* @author Joa z)hK 2JD
*/ 3%'`^<-V
publicclass Result { e2c'Wab
MS;^:t1`
private Page page; }d}gb`Du
QD,m`7(
private List content; tcj"rV{G
<@(\z
/** >u>
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* The default constructor b\ED<'
*/ wA$7SWC
public Result(){ f4 S:L&
super(); ]Ik~TW&
} }&=l)\e
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/** P_3IFHe
* The constructor using fields $a~
* N9 M}H#
* @param page o4p5`jOG@
* @param content hx0 t!k(3
*/ zgjgEhnvU
public Result(Page page, List content){ 4A@HR
this.page = page; Wd7*7']
this.content = content; 8J'5%$3u
} B0b|+5WhR
>97YK =
/** CbM~\6R
* @return Returns the content. y`zdI_!7
*/ u W,J5!
publicList getContent(){ e*T^:2oRl
return content; aQmS'{d?^
} CrI<rD%'
&'12,'8
/** _DSDY$Ec
* @return Returns the page. Zuzwc [Z1
*/ xBxiBhqzF
public Page getPage(){ xMk>r1Ud
return page; c\ZI
5&4jT
} X[?fU&
}Y7P2W+4?
/** _qPKdGoM
* @param content `/T.u&QF
* The content to set. 1;~sNSTo
*/ W^3 Jg2gE
public void setContent(List content){ \"ogQnmz
this.content = content; 0"e["q{|
} p+iNi4y@
9`92
>
/** VE]TT><
* @param page #L!`n)J"
* The page to set. Ec<33i]h*p
*/ UucX1%
publicvoid setPage(Page page){ r8 YM#dF
this.page = page; f`ibP6%
} mxCneX
} *^@b0f~vj
>uZc#Zt
Hx+r9w
?a,#p
6P@K]jy& n
2. 编写业务逻辑接口,并实现它(UserManager, cu1!WD
8zMGpY#
UserManagerImpl) rEp\ld
java代码: C"n!mr{srt
O\Y*s
Zq33R`
/*Created on 2005-7-15*/ a :*N0
package com.adt.service; yH:p*|% :
ih)\P0wed
import net.sf.hibernate.HibernateException; >{Ayzz>v
1^]IuPxq
import org.flyware.util.page.Page; N}/V2K]Q
lPz`?Hn
import com.adt.bo.Result; ]lKUpsQI
d1.@v;
/** lmcgOTT):
* @author Joa S^~"#
*/ , SUx!o
publicinterface UserManager { F}mt
*UcMG
GTbV5{Ss
public Result listUser(Page page)throws sQ\HIU%]
W"s/8;
HibernateException; nT:<_'!
p&\QkI=
} l@w\
Vxr
?r|iZKa
& +`g~6U
<
`;Mf>V
[}Xw/@Uc;
java代码: Wx#l}nD
? Lxc1
Z~(X[Zl
:
/*Created on 2005-7-15*/ V G7#C@>Z
package com.adt.service.impl; vt"bB
bO$KV"*!
import java.util.List; r-S%gG}~E
v"
#8^q
import net.sf.hibernate.HibernateException; Edc3YSg%;
7?g({]
import org.flyware.util.page.Page; IN6L2/Q
import org.flyware.util.page.PageUtil; eI`%J3BxR
(5`(H.(
import com.adt.bo.Result; A]QGaWK
import com.adt.dao.UserDAO; ;XNC+mPK
import com.adt.exception.ObjectNotFoundException; KRm)|bgE
import com.adt.service.UserManager; 9qi|)!!L
0 7qjWo/t
/** |Z>}#R!,P
* @author Joa 1:7fV@jw
*/ d$\n@}8eZp
publicclass UserManagerImpl implements UserManager { 1M)88&
)X *_oH=
private UserDAO userDAO; 1)}hzA
u-.5rH l
/** Q>X1 :Zn3
* @param userDAO The userDAO to set. pdN8hJ
*/ zO9WqP_`iR
publicvoid setUserDAO(UserDAO userDAO){ c<q33dZ!*
this.userDAO = userDAO; D)4#AI
} n|.eL8lX.<
:Id8N~g
/* (non-Javadoc) [KGj70|~
* @see com.adt.service.UserManager#listUser GRj [2I7:
TRgj`FG
(org.flyware.util.page.Page) o6x8jz
*/ yN[i6oe
public Result listUser(Page page)throws .j)DE}[q>
4Af7x6a;
HibernateException, ObjectNotFoundException { WuWOC6^
int totalRecords = userDAO.getUserCount(); ~.e~YI80
if(totalRecords == 0) m/g[9Y
throw new ObjectNotFoundException UaXIrBc
6R3/"&P(/#
("userNotExist"); Y*jkUQ
page = PageUtil.createPage(page, totalRecords); Wl&6T1A`"
List users = userDAO.getUserByPage(page); iqX%pR~Yo
returnnew Result(page, users); BUI#y `J
} ;x|?N*
|P9Mhf N
} q2Sc{E>[
`}
'o2oZnG
%dd B$(
"_rpErm
}
#8v l2qWbi
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 HD$r<bl
>Wd=+$!I
询,接下来编写UserDAO的代码: 4e[ 0.2?
3. UserDAO 和 UserDAOImpl: 2xy{g&G
java代码: 5
r<cna
S}/ZHo
!_>/ r
/*Created on 2005-7-15*/ }*P;kV
package com.adt.dao; ucLh|}jJ5
h=au`o&CG
import java.util.List; C?g*c
\@NnL\t
u
import org.flyware.util.page.Page; [--] ?Dr
@[$q1Nm
import net.sf.hibernate.HibernateException; +q432ZG
7S_"h*Ud
/** Hnvs{KC`
* @author Joa o(i?_4E
*/ @-1VN;N
publicinterface UserDAO extends BaseDAO { YpSK|(
a\MJh+K
publicList getUserByName(String name)throws Hs.5@ l
q"g4fzCD
HibernateException; .'1]2/ad
=p8iYtI
publicint getUserCount()throws HibernateException; We"\nOP
l2!ztK1^
publicList getUserByPage(Page page)throws !*k'3rKOW
`LTD|0;
HibernateException; 2F,?}jJ.K
unN*L
} riglEA[^
FePWr7Ze
RDqQ6(e"
Zq/=uB7Z
`g}en%5b\
java代码: 2DBFY1[Pk
5.Nc6$
N
/ Kj;%
/*Created on 2005-7-15*/ 6,p;8I
package com.adt.dao.impl; /-ewCCzZV
Pz' Zn
import java.util.List; F
n*+uk
=~$)Ieu
import org.flyware.util.page.Page; U4y ?z
4Z{ r
import net.sf.hibernate.HibernateException; N?s5h?
import net.sf.hibernate.Query; 2ZMVYa2%(
u|ru$cIo
import com.adt.dao.UserDAO; `=W#owAF
[k,FJ5X
/** d6e]aO=g
* @author Joa LaIH3!M3
*/ GmN~e*x>p
public class UserDAOImpl extends BaseDAOHibernateImpl m&6I@S2
"4QD\k5
implements UserDAO { `uqsYY`V
HO8x:2m
/* (non-Javadoc) RjHKFB2
* @see com.adt.dao.UserDAO#getUserByName Z9I
?j1K|!
.|J-(J<>[.
(java.lang.String) vau#?U".}>
*/ 4g/Ly8
publicList getUserByName(String name)throws lJ4&kF=t
3)~z~p7
HibernateException { 3%V VG~[
String querySentence = "FROM user in class 1GgG9I
z]Mu8
com.adt.po.User WHERE user.name=:name"; 6Y=MW{=F
Query query = getSession().createQuery `SESj)W(y
sCRmLUD
(querySentence); cD4H@!=a
query.setParameter("name", name); McQWZ<
return query.list(); ulY<4MN
} P/~kX_
8IihG
\
/* (non-Javadoc) JI~@H /j
* @see com.adt.dao.UserDAO#getUserCount() ~VO?P fxZ
*/ :e TzjW=
publicint getUserCount()throws HibernateException { 'ul~f$
V
int count = 0; (L8z<id<z
String querySentence = "SELECT count(*) FROM O(44Dy@2
PqwoZo0j
user in class com.adt.po.User"; %-, -:e
Query query = getSession().createQuery ~]lVixr9
'uV;)~
(querySentence); Eh?,-!SUQn
count = ((Integer)query.iterate().next -]vPF|
c9xc@G!
()).intValue(); ,W&::/2<7
return count; RVe UQ%
} 5Og=`T
A^hFRAg4
/* (non-Javadoc) hQDZ%>
* @see com.adt.dao.UserDAO#getUserByPage j[YO1q*
P<gr=&
(org.flyware.util.page.Page) %N-f9o8
*/ Mhj.3nN
publicList getUserByPage(Page page)throws km#Rh^
oSqkAAGz\
HibernateException { _,9/g^<
String querySentence = "FROM user in class 6`hHx=L
O'<cEv'B*
com.adt.po.User"; 1W2hd!J7C
Query query = getSession().createQuery {nlqQ.jO
_0]{kB.$_
(querySentence); B[6y2+6$0
query.setFirstResult(page.getBeginIndex()) .6nNqGua1
.setMaxResults(page.getEveryPage()); C
Ejf&n
return query.list(); =^A/&[&31
} z>./lu\
+oMe\wYR$r
} LTc=D
h$y0>eMWs
s+yX82Y
} h0
)
O
E56J-*}x
至此,一个完整的分页程序完成。前台的只需要调用 a6fqtkZ x
00)=3@D
userManager.listUser(page)即可得到一个Page对象和结果集对象 jZvQMW
WAt | J2
的综合体,而传入的参数page对象则可以由前台传入,如果用 /5c;,.hm1R
]f"l4ay@M
webwork,甚至可以直接在配置文件中指定。 x_TtS|
\+B+M 7
下面给出一个webwork调用示例: G_UxR9Qo
java代码: %4rPkPAtrp
e^ygQ<6%
s9-aPcA
/*Created on 2005-6-17*/ F)g.xQ
package com.adt.action.user; 92HxZ*t7km
AmmUoS\
import java.util.List; g` QbJ61a
]ZOzqh_0C
import org.apache.commons.logging.Log; `CXAE0Fx
import org.apache.commons.logging.LogFactory; E
_DSf
import org.flyware.util.page.Page; SecZ5(+=
- &/n[EE
import com.adt.bo.Result; =9ISsI\Y6
import com.adt.service.UserService; D.\s mk
import com.opensymphony.xwork.Action; :{Crc
J3B]JttU
/** T m0m$l
* @author Joa BejeFV3
*/ (X"WEp^Q{I
publicclass ListUser implementsAction{ Gf{FFIe(
AK*F,H9
privatestaticfinal Log logger = LogFactory.getLog U0kEhMIIf
_jW}p-j
(ListUser.class); H,!3s<1
?!J{Mrdn
private UserService userService; m
pWmExQ
S%7^7MSqA
private Page page; BiUOjQC#
.v3~2r*&
privateList users; naT;K0T=
. !|3a
/* ,\BGxGNAmV
* (non-Javadoc) XfXqq[\N
* Iw0Q1bK(
* @see com.opensymphony.xwork.Action#execute() StP7t
*/ Q'~2,%3<
publicString execute()throwsException{ Ox` +Z0)a
Result result = userService.listUser(page); n"1LVJN7
page = result.getPage(); z5G$'
users = result.getContent(); clZjb
return SUCCESS; 0{PRv./`
} p/a)vN+*x'
B>CG/]
/** |oSx*Gh
* @return Returns the page. :u7y k@
*/ uZ-yu|1
public Page getPage(){ 6-@
X
return page; Y!6,ty'
} ]~SOGAFW
JPX5Jm()
/** Cku&s
* @return Returns the users. uV:;q>XM'%
*/ :-=,([TJ
publicList getUsers(){ vElVw.
P
return users; zd+_
BPT
} ;MqH)M
cj:!uhZp7
/** Ed%8| M3
* @param page J0e~s
* The page to set. RfMrGC^?
*/ tnbtfG;z#
publicvoid setPage(Page page){ ?2b*FQe
this.page = page; HY,+;tf2r
} 2sJj -3J
94umk*ib
/** +@Oo)#V|.
* @param users fXPD^}?Ux4
* The users to set. a_UVb'z
*/ k:Iz>3O3]
publicvoid setUsers(List users){ S0_#h)
this.users = users; BTwLx-p9t
} m8q3Pp
9}{i8
<