Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 dq
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1u\kxlZ
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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 N \Wd0b
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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 ;DN:AgXP
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分页支持类: O:86*
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java代码: HZ.Jc"+M
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package com.javaeye.common.util;
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import java.util.List; jy2@t *
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publicclass PaginationSupport { g"&e*fF
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publicfinalstaticint PAGESIZE = 30; r1!]<= &\
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privateint pageSize = PAGESIZE; eV x
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privateList items; 9e xHR&>{
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privateint totalCount; xgQ]#{tG
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privateint[] indexes = newint[0]; ko<iG]Dv'
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privateint startIndex = 0; TPeBb8v8D
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public PaginationSupport(List items, int OJH:k~]0!
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totalCount){ dS[="Set
setPageSize(PAGESIZE); H@R2mw
setTotalCount(totalCount); fpK`
setItems(items); =P"Sm
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setStartIndex(0); Z" !+p{u
} 68v59)0U
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public PaginationSupport(List items, int J@I-tS
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totalCount, int startIndex){ w}jH,Ew
setPageSize(PAGESIZE); <fLk\
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setTotalCount(totalCount); D@yuldx'/
setItems(items); 8*V8B=q}K
setStartIndex(startIndex); ^-'t`mRl]d
} ->S6S_H/+&
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public PaginationSupport(List items, int M+N7JpR
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totalCount, int pageSize, int startIndex){ b[I;6HW
setPageSize(pageSize); 2r]!$ hto
setTotalCount(totalCount); rLm:qu(F1
setItems(items); dGb]`* E
setStartIndex(startIndex); c*"TmDY
} i%R2#F7I
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publicList getItems(){ U.@j!UrZ
return items; ;%R+]&J
} `Y`QxU!d%
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publicvoid setItems(List items){ L'J Ekji"
this.items = items; 7v~\c%1V
} FSvtiNW<
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publicint getPageSize(){ %Jr6pmc
return pageSize; = +uUWJ&1G
} ?+bDFM}
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publicvoid setPageSize(int pageSize){ vG<JOxP
this.pageSize = pageSize; wPl!}HNf
} o5N];Nj
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publicint getTotalCount(){ \q8D7/q
return totalCount; AjQ^
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} U*'
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publicvoid setTotalCount(int totalCount){ lj1wTiaI(
if(totalCount > 0){ h|!F'F{
this.totalCount = totalCount; :K3nJ1G&
int count = totalCount / c9dH ^t
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pageSize; Wh,{|R[
if(totalCount % pageSize > 0) ,cvLvN8
count++; gJyFt8Z<
indexes = newint[count]; QPH2TXw
for(int i = 0; i < count; i++){ M- 2:$;D
indexes = pageSize * "$Wi SR
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i; *yv@-lP5s
} ]xhmM1$
}else{ 2wWL]`(E
this.totalCount = 0; NAj1ORy4pX
} s68EzFS
} .~4>5W"u
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publicint[] getIndexes(){ m4@y58n=
return indexes; d8b'Gjwtw
} fNi&1J-/
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publicvoid setIndexes(int[] indexes){ 6NCa=9
this.indexes = indexes; 6t5)rlT
} dm Lgt)-t
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publicint getStartIndex(){ Musz+<]
return startIndex; ]u_^~
} `F>1xMm
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publicvoid setStartIndex(int startIndex){ VZ*Q|
if(totalCount <= 0) Dk|<&uVV
this.startIndex = 0; E\r5!45r
elseif(startIndex >= totalCount) *|x2"?d-F:
this.startIndex = indexes
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[indexes.length - 1]; gFvFd:"uZ
elseif(startIndex < 0) ;<#fZ0(l;
this.startIndex = 0; #[*e$C
else{ <?P UF,
this.startIndex = indexes ^yKP 99(
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[startIndex / pageSize]; PZ-|W
} i4.s_@2Y
} S\Qh#yFT
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publicint getNextIndex(){ /|y3M/;F
int nextIndex = getStartIndex() + }[PbA4l.g
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pageSize; gU/\'~HG
if(nextIndex >= totalCount) V|{ )P@Q
return getStartIndex(); #kX=$Bzk
else I0O)MR<
return nextIndex; Zg7~&vs$
} xZS
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publicint getPreviousIndex(){ sp[nKo^
int previousIndex = getStartIndex() - {"e/3
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pageSize; 9il!w
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if(previousIndex < 0) 4j)Y>
return0; +*g[hRw[
else 5.xvOi|.
return previousIndex; <27B*C M
} h^$>{0"
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} %|Vo Zx ^
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抽象业务类 3l>P>[<o
java代码: IqEY.2KN
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/** &I?1(t~hT
* Created on 2005-7-12 7(~^6Ql!
*/ 96vv85g
package com.javaeye.common.business; 3OFv_<6
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import java.io.Serializable; <HG~#oBRq
import java.util.List; Bw"L!sZ
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import org.hibernate.Criteria; (H+'sf^h
import org.hibernate.HibernateException; 5Zn3s()
import org.hibernate.Session; -MHu BgYJ-
import org.hibernate.criterion.DetachedCriteria; uGLVY%N
import org.hibernate.criterion.Projections; *NDLGdQqz
import v{=-#9-4
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org.springframework.orm.hibernate3.HibernateCallback; X!,Ngmw.
import -H.;73Kb[
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org.springframework.orm.hibernate3.support.HibernateDaoS h&yaug,.
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upport; w^`n
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import com.javaeye.common.util.PaginationSupport; <`|}bt
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public abstract class AbstractManager extends o?p) V^7
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HibernateDaoSupport { `p#A2ApA
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privateboolean cacheQueries = false; `?=AgGg
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privateString queryCacheRegion; 2E2J=Do
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publicvoid setCacheQueries(boolean uaJ5'*
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cacheQueries){
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this.cacheQueries = cacheQueries; .D4D!!
} $!obpZ~ }
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publicvoid setQueryCacheRegion(String -+Q,xxu
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queryCacheRegion){ Fl*@@jQ8cV
this.queryCacheRegion = !k<+-Lf:2
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queryCacheRegion; &.(ZO]
} e|MyA?`
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publicvoid save(finalObject entity){ wM!QU{Lz
getHibernateTemplate().save(entity); A|Y\Y }
} y62;&{?m
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publicvoid persist(finalObject entity){ 5QSd$J
getHibernateTemplate().save(entity); `i{o8l
} >r]# 77d
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publicvoid update(finalObject entity){ g4Hq<W"
getHibernateTemplate().update(entity); =$BgIt
} tvb hWYe
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publicvoid delete(finalObject entity){ X:62)^~'
getHibernateTemplate().delete(entity); }doj4
} Tm3$|+}$f
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publicObject load(finalClass entity, 9=<
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finalSerializable id){ E>'pMw
return getHibernateTemplate().load NoYu"57\
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(entity, id); ?LNwr[C0
} oY.JK
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publicObject get(finalClass entity, L</"m[
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finalSerializable id){ Rut6m5>
return getHibernateTemplate().get /
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(entity, id); 5@Py`
} Nr(WbD[T
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publicList findAll(finalClass entity){ m,up37-{
return getHibernateTemplate().find("from 9Hc#[Ml
n$=n:$`q
" + entity.getName()); }W|CIgF*
} gJF;yW4
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publicList findByNamedQuery(finalString Nxt/R%(
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namedQuery){ {UPIdQ'g
return getHibernateTemplate HQUL?URt
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().findByNamedQuery(namedQuery); KR522YW
} uNRGbDMA=
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publicList findByNamedQuery(finalString query, '*~{1gG `
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finalObject parameter){ `b% /.%]$
return getHibernateTemplate
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().findByNamedQuery(query, parameter); foJ|Q\Z,T
} iySmNI
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publicList findByNamedQuery(finalString query, #Ta@A~.L
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finalObject[] parameters){ _D+7w'8h
return getHibernateTemplate +b{h*WWdj
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().findByNamedQuery(query, parameters); I}8F3_b,#
} { aB_t%`w
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publicList find(finalString query){ 6"=e+V@
return getHibernateTemplate().find %
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(query); bC@b9opD
} |w>DZG!}1-
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publicList find(finalString query, finalObject m3|,c[M1
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parameter){ jgO{DNe(=
return getHibernateTemplate().find 67sb
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(query, parameter); c9ZoO;
} {Rz`)qqE
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public PaginationSupport findPageByCriteria Jq; }q63:
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(final DetachedCriteria detachedCriteria){ X:!%"K%}
return findPageByCriteria k1cBMDSokO
#/1Bam6
(detachedCriteria, PaginationSupport.PAGESIZE, 0); DV.MvFV
} fcBSs\\C~
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public PaginationSupport findPageByCriteria ^1nf|Xj[
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(final DetachedCriteria detachedCriteria, finalint #".{i+3E
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startIndex){ S_WY91r
return findPageByCriteria oC?b]tzj
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(detachedCriteria, PaginationSupport.PAGESIZE, yqYX<<!V
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startIndex); =kCpCpET
} 9\n}!{@i
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public PaginationSupport findPageByCriteria EgO4:8$h
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(final DetachedCriteria detachedCriteria, finalint uL= \t=
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pageSize, u9&p/qMx2
finalint startIndex){ i4-L!<bJ
return(PaginationSupport) {:dE_tqo
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getHibernateTemplate().execute(new HibernateCallback(){ cK?t]%S
publicObject doInHibernate Q{a!D0;4v
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(Session session)throws HibernateException { 8q0 .yhb
Criteria criteria = k+i=0P0mf
mPh;
detachedCriteria.getExecutableCriteria(session); <0vvlOL5
int totalCount = Z*Y?"1ar
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((Integer) criteria.setProjection(Projections.rowCount 'nLv0.7*
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()).uniqueResult()).intValue(); Kfr?sX
criteria.setProjection N" 8o0>
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(null); 9QYU
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List items = $ OR>JnV
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criteria.setFirstResult(startIndex).setMaxResults ywdNwNJ
Y#m0/1-
(pageSize).list(); KOxD%bX_
PaginationSupport ps = b9v Kux
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new PaginationSupport(items, totalCount, pageSize, A<Na,EC
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startIndex); z/ i3
return ps; ,=ICSS~9l
} Vz#cb5:g
}, true); V&>7i9lEz
} y^XwJX-f
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public List findAllByCriteria(final COT;KC6
n
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DetachedCriteria detachedCriteria){ b
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return(List) getHibernateTemplate w9oiu$7),
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().execute(new HibernateCallback(){ X}Csl~W8in
publicObject doInHibernate byMO&Lb*
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(Session session)throws HibernateException { _Nj;Ni2rD
Criteria criteria = "K@os<
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detachedCriteria.getExecutableCriteria(session); }Yt0VtLt
return criteria.list(); v3/cNd3
} QO
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}, true); 2D!'7ZD
} 5M(?_qj
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public int getCountByCriteria(final 3Q#VD)
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DetachedCriteria detachedCriteria){ JrQN-e!
Integer count = (Integer) s)N1@RBR
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getHibernateTemplate().execute(new HibernateCallback(){ x}roPhZ
publicObject doInHibernate Oo0$n]*;W
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(Session session)throws HibernateException { x?%vqg^r
Criteria criteria = tsk}]@W
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detachedCriteria.getExecutableCriteria(session); AiyjrEa%
return <wuP*vI"h
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criteria.setProjection(Projections.rowCount 0Icyi#N
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()).uniqueResult(); z(m*]kpL"
} vSX
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}, true); D"o>\Q
return count.intValue(); ]EK"AuEz`
} '[HFIJ0K!
} saV3<zgx
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用户在web层构造查询条件detachedCriteria,和可选的 z!1j8o2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 7e40 }n
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PaginationSupport的实例ps。 1S=I(n?E
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ps.getItems()得到已分页好的结果集 _#L
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ps.getIndexes()得到分页索引的数组 4@bL` L)
ps.getTotalCount()得到总结果数 p5bH-km6
ps.getStartIndex()当前分页索引 YF;8il{p
ps.getNextIndex()下一页索引 Ri,UHI4 W
ps.getPreviousIndex()上一页索引 CEUR-LK0
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 A$oYw(m#
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 e8[*=&
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一下代码重构了。 ;Y~;G7
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我把原本我的做法也提供出来供大家讨论吧: bc&:v$EGy
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首先,为了实现分页查询,我封装了一个Page类: )kkO:j
java代码: 0zEn`rq&
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/*Created on 2005-4-14*/ UdY9*k
package org.flyware.util.page; |mKd5[$
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/** eF2<L [9
* @author Joa P8TiB
* Qn<<&i~
*/ 0h; -Yg
publicclass Page { Ii"cDH9
rbJ-vEzo.#
/** imply if the page has previous page */ l&C%oW
privateboolean hasPrePage; O}D]G%,m
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/** imply if the page has next page */ eLt6Hg)s`9
privateboolean hasNextPage; 1LE8,Gm&
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/** the number of every page */ hwO]{)%
privateint everyPage; }R
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/** the total page number */ 7f`jl/
privateint totalPage; O|OPdD
& XrV[d[>
/** the number of current page */ KDY~9?}TM
privateint currentPage; <H 3}N!
:Ct}||9/
/** the begin index of the records by the current ikY=}
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query */ ;`xu)08a
privateint beginIndex; mp5]=6~:m
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/** The default constructor */ '[A>eC++
public Page(){ mB!81%f%|
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} A5nu`e9&
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/** construct the page by everyPage *D\nsJ*g
* @param everyPage IP~g7`Y
* */ UL{Xe&sT
public Page(int everyPage){ )JZfC&,
this.everyPage = everyPage; #S1)n[
} fCTjTlh
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/** The whole constructor */ bhg"<I
public Page(boolean hasPrePage, boolean hasNextPage, ?49wq4L;a
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int everyPage, int totalPage, "#p)Z{v"!
int currentPage, int beginIndex){ N/y.=]
this.hasPrePage = hasPrePage; 5v?6J#]2
this.hasNextPage = hasNextPage; _o`'b80;
this.everyPage = everyPage; n,fUoS
this.totalPage = totalPage; R Jg# A`
this.currentPage = currentPage; 1W-!f%
this.beginIndex = beginIndex; y[}BFUy
} QALMF rWH
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/** +]AE}UXZoh
* @return cW3;5
* Returns the beginIndex. .*y{[."!
*/ b^%4_[uRu
publicint getBeginIndex(){ Qs4Jl ;Y _
return beginIndex; zg^5cHP\
} >w
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/** iedoL0#
* @param beginIndex :qnRiK]
* The beginIndex to set. JM M\
*/ VNMhtwmK,
publicvoid setBeginIndex(int beginIndex){ jCy2bE
this.beginIndex = beginIndex; %5uuB4P&|$
} )~WxNn3rx
8IVKS>
/** 5[I9/4,
* @return H p1cVs
* Returns the currentPage. T$'Ja'9Kj
*/ R(hqBa/V
publicint getCurrentPage(){ 1 iE
return currentPage; lv{Qn~\y&
} n2TvPt\
)+ S" `
/** 8XTVpf4
* @param currentPage zf^!Zqn[8z
* The currentPage to set. ,g/ UPK8K=
*/ *%g*Np_P
publicvoid setCurrentPage(int currentPage){ '1bdBx\<.
this.currentPage = currentPage; X3q'x}{
} }G-qOt
psYfz)1;
/** rYc?y
* @return lKe aI
* Returns the everyPage. f9#B(4Tgi
*/ BPC$ v\a
publicint getEveryPage(){ g*8sh
return everyPage; )L^WD$"'Q
} :egSW2"5S
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/** R`/nsou
* @param everyPage 3"q%-M|+Q
* The everyPage to set. R{4O*i8#
*/ ]1gt|M^
publicvoid setEveryPage(int everyPage){ @aBZ|8
this.everyPage = everyPage; A87Tyk2Pi
} 20hE)!A
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/** 0;V2>!
* @return U4Qc$&j>
* Returns the hasNextPage. sHAzg^n}r
*/ \z<'6,b
publicboolean getHasNextPage(){ 3``$yWWg
return hasNextPage; >)!"XFbb
} 2)mKcUL-
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/** )D(XDN
* @param hasNextPage AEEy49e
* The hasNextPage to set. As78yfK
*/ pcL02W|J
publicvoid setHasNextPage(boolean hasNextPage){ G!%1<SLi.
this.hasNextPage = hasNextPage; vsLn@k3
} /I: d<A
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/** ^${-^w@,%V
* @return c~dX8+
* Returns the hasPrePage. ptrLnJ|%
*/ <y~`J`-
publicboolean getHasPrePage(){ Lt=#tu&d
return hasPrePage; Cm>8r5LG
} U<o,`y[Tn
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/** ,]Hn*\@p[c
* @param hasPrePage l6)*u[}E
* The hasPrePage to set. i1u &-#k
*/ d(R3![:
publicvoid setHasPrePage(boolean hasPrePage){ K2)),_,@5+
this.hasPrePage = hasPrePage; XPb7gd"%W
} :*@=px
} fSbH
/** e,8C}
2
* @return Returns the totalPage. #y2="$V
* UB?a-jGZK
*/ :aco$ZNH5
publicint getTotalPage(){ Qp%kX@Z'
return totalPage; llQDZ}T
} kg+"Ta[9
]Kil/Y
/** H6*F?a`)I
* @param totalPage ;J2=6np
* The totalPage to set. ^'[Rb!Q8
*/ `P"-9Ue=
publicvoid setTotalPage(int totalPage){ @;Yb6&I;
this.totalPage = totalPage; F y^!*M-
} o^_z+JFwb
KJJ8P`Kx
} Ge|caiH1I
Z#MPlw0B
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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 8v c4J5
5U%uS^%DP
个PageUtil,负责对Page对象进行构造: :6Bk<
java代码: PK!=3fK4\F
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/*Created on 2005-4-14*/ ld`oIEj!P_
package org.flyware.util.page; c tTbvXP
)|'? uN7
import org.apache.commons.logging.Log; CP/`ON
import org.apache.commons.logging.LogFactory; jbfMTb4
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/** swe6AQ-
* @author Joa
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* W<v?D6dFq
*/ 0M-Zp[w\-
publicclass PageUtil { X~%Wg*Hm
0 UjT<t^F
privatestaticfinal Log logger = LogFactory.getLog &c?-z}=G
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(PageUtil.class); HrWXPac
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/** aW$7:<A{
* Use the origin page to create a new page ($[pCdY
* @param page GS \-
* @param totalRecords 0t6s20*q
* @return GP[;+xMBh
*/ Kl\A&O*{
publicstatic Page createPage(Page page, int l% K9Ke
i#&]{]}Qv
totalRecords){ vQYd!DSh
return createPage(page.getEveryPage(), Xy=|qu
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page.getCurrentPage(), totalRecords); n"d~UV^Uw
} NTls64AS.
4|7L26,]5
/** N{
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* the basic page utils not including exception Y |n_Ro^~
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handler Y Q3%vH5#y
* @param everyPage HFvhrG
* @param currentPage 86.!sQ8b
* @param totalRecords D("['`{
* @return page FHqa|4Ie
*/ '+Ts IJh
publicstatic Page createPage(int everyPage, int C&K%Q3V
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currentPage, int totalRecords){ XNd:x{
everyPage = getEveryPage(everyPage); _N0x&9S$
currentPage = getCurrentPage(currentPage); q$~S?X5\
int beginIndex = getBeginIndex(everyPage, Fu!:8Wp!(
I)O%D3wfMW
currentPage); )"=BbMfhu
int totalPage = getTotalPage(everyPage, r]"
>
(a@cK,
totalRecords); b{(!Ls_ &
boolean hasNextPage = hasNextPage(currentPage, WcbJ4Ore
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totalPage); bP(V#6IJ8
boolean hasPrePage = hasPrePage(currentPage); "n:L<F,g
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returnnew Page(hasPrePage, hasNextPage, "f3, w
everyPage, totalPage, 31<hn+pE&
currentPage, u,4,s[
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beginIndex); _nOio ?
} !fyE
Hk
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privatestaticint getEveryPage(int everyPage){ JxNjyw
return everyPage == 0 ? 10 : everyPage; 2gb49y~
} ZLxe$.V_
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privatestaticint getCurrentPage(int currentPage){ C7eaioW$
return currentPage == 0 ? 1 : currentPage; 0 l
G\QT
} ^kt#[N
6@; w%Ea
privatestaticint getBeginIndex(int everyPage, int 73 Tg{~
O/iew3YF
currentPage){ Xj?j1R>GB
return(currentPage - 1) * everyPage; %pe7[/
} 0ot=BlMu
{;=+#QK/
privatestaticint getTotalPage(int everyPage, int nLJ]tpw^DH
h:Npi
`y
totalRecords){ t.485L%
int totalPage = 0; @_h/%>0
nYTI\f/8v
if(totalRecords % everyPage == 0) =r:D]?8oC
totalPage = totalRecords / everyPage; H2p1gb#
else %~ZOQ%c1
totalPage = totalRecords / everyPage + 1 ; S'B7C>i`#N
C(7LwV
return totalPage; Hg*6I%D[So
} `61VP-r
M@
! {m
privatestaticboolean hasPrePage(int currentPage){ (*^_wq-;
return currentPage == 1 ? false : true; / QSK$ZDC
} 3[-L'!pOX3
?v8B;="#w
privatestaticboolean hasNextPage(int currentPage, W(a=ev2sa
4}LGE>
int totalPage){ e
J2wK3R
return currentPage == totalPage || totalPage == )TVyRY Z1
x]Nq|XK
0 ? false : true; ^h4Q2Mv o
} :X,1KR
g>T'R Vb
[[LCEw
} xH; 4lw
MpGWt#
htkn#s~=
Jg/WE1p>
BVC\~j
j
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。 : ,LX3,
|!flR? OU
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 w3fi2B&q
)xT_RBR
做法如下: gMFTZQsP
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 mVP@c&1w?
\
Lrg:
的信息,和一个结果集List: q#c\
java代码: +f;z{)%B
*-ZJF6
!H~G_?Mf\O
/*Created on 2005-6-13*/ 0waQw7
E
package com.adt.bo; [1G4he%
DLJu%5F
import java.util.List; rP^2MH"
zG+oZ
import org.flyware.util.page.Page; &NB[:S=
Ag#p )
/** W5HC7o\4
* @author Joa <G}>Gk8x
*/ '!b1~+PV
publicclass Result { Nq9@^ E-{M
KZsSTB6J
private Page page; {CYFM[V
yLipuMNV
private List content; $l7
<j_C
*=UEx0_!q
/** OiJ1&Fz(
* The default constructor s-3vp
*/ ,K,n{3]
public Result(){ !1-:1Whz8
super(); '<4/Md[
} FJ}/g
?
s{'r'`z.
/** sMs 0*B-[
* The constructor using fields bt-y6,> +E
* u4rG e!
* @param page 'HH[[9Q
* @param content zxT&K|
*/ u\Tq5PYXt
public Result(Page page, List content){ D)K/zh)
this.page = page; '\[GquK;P
this.content = content; `G@]\)-!
} WVir[Kv%
4$@5PS#,
/** 118A6qyi
* @return Returns the content. rB<
UOe
*/ EO:i+e]=
publicList getContent(){ j1_CA5V
return content; OU/PB
} &3:-(:<U
'>@evrG
/** }BzV<8F
* @return Returns the page. TMT65X!
*/ /!P,o}l7
public Page getPage(){ F
MHpa
return page; K.JKE"j)d
} Oz-X}eM
jLM1~`&
/** Dc}-wnga
* @param content q~T*R<S
* The content to set. !Hr~B.f7
*/ &?#V*-;^
public void setContent(List content){ HX7"w
this.content = content; 69p>?zn
} OtBVfA:[
R]/3`X9!d>
/** qa.nm4"6+
* @param page +%UfnbZ
* The page to set. /hQTV!\u
*/ kL*
DU`
publicvoid setPage(Page page){ )4toBDg"
this.page = page; @_J~zo
} hV)D,oN3
} si.ZTG9m
9l]+rs+
(1^AzE%U+Z
B8:G1r5G/
&z+nNkr?yN
2. 编写业务逻辑接口,并实现它(UserManager, W.'#pd
zn@<>o8hU
UserManagerImpl) SDwTGQ/0
java代码: +vIpt{733
.D!0$W mOZ
FAX|.!US*p
/*Created on 2005-7-15*/ KLBU8%
package com.adt.service; (y*7
gf
NTbmI$(
import net.sf.hibernate.HibernateException; >-*rtiE
gFizw:l
import org.flyware.util.page.Page; iyKAw
HkVnTC
import com.adt.bo.Result; {p[{5k 0
@.0>gmY;:
/** Fku~'30
* @author Joa Z-z^0QO
*/ z$4g9
publicinterface UserManager { z6)b XL[f
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public Result listUser(Page page)throws =.a}
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HibernateException; b
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<`rmQ`(}s
}
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T$rhz)_q
C~-x637/
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js;p7wi
java代码: o@:${>jw
nWb*u
@6h,#8#
/*Created on 2005-7-15*/ @+Yql
package com.adt.service.impl; .8e]-^Z
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import java.util.List; 9^;Cz>6s
)l?1dR:sP
import net.sf.hibernate.HibernateException; 6Cw+
x3DUz
import org.flyware.util.page.Page; uPCzs$R
import org.flyware.util.page.PageUtil; /JsA[}.6
"o_s=^U
import com.adt.bo.Result; dhrh "x_?:
import com.adt.dao.UserDAO; cD.afy
import com.adt.exception.ObjectNotFoundException; E$SYXe [,
import com.adt.service.UserManager; wnUuoX(
,5V w^@F
/** WbJ|]}hJ\
* @author Joa pPL)!=o!
*/ HQ /D )D
publicclass UserManagerImpl implements UserManager { 4g4[n7
_D+pJ{@W
private UserDAO userDAO; gy5 ^JL
)j,Y(V$P
/** de=){.7Y
* @param userDAO The userDAO to set. f/xQy}4+~E
*/ i4T=4q
publicvoid setUserDAO(UserDAO userDAO){ s.|OdC>U =
this.userDAO = userDAO; CWBlDz
} w#6)XR|+,.
HuT4OGBFpC
/* (non-Javadoc) R7\T.;8+
* @see com.adt.service.UserManager#listUser Cv[_N%3[
J.;!l
(org.flyware.util.page.Page) OQ(w]G0LP
*/ + Vv+<M
public Result listUser(Page page)throws lbs0i
Xwp6]lx
HibernateException, ObjectNotFoundException { mH.c`*
int totalRecords = userDAO.getUserCount(); wqxChTbs
if(totalRecords == 0) 0oK_u Y
4g
throw new ObjectNotFoundException cMs8D
ygK@\JHn
("userNotExist"); 3vXa#f>P<
page = PageUtil.createPage(page, totalRecords); kB`
@M>[
List users = userDAO.getUserByPage(page); e"#QUc(
returnnew Result(page, users); niA>afo
} ($nQmr;t
a =
*'
} Ztl?*zL
'm=TBNQTS
A"tE~m;"7
o5B]? ekpq
6Y`rQ/F
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]l7 r M"
~nJ"#Q_T
询,接下来编写UserDAO的代码: k"3@G?JY
3. UserDAO 和 UserDAOImpl: ;!S i_b2
java代码: @.&KRAZ
shgZru
;
,Nvg6c
/*Created on 2005-7-15*/ ~6A;H$dr
package com.adt.dao; Sw.k,p*r
!C(U9p. 0
import java.util.List; ^jbjHI&
F/SYmNp
import org.flyware.util.page.Page; R ;k1(p
VUon>XQ
G
import net.sf.hibernate.HibernateException; VTUSM{TC
iE0x7x P_
/** R
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* @author Joa 7}1Z7"?
*/ Tnv,$KOhs
publicinterface UserDAO extends BaseDAO { BUCPO}I
'4Drs}j5
publicList getUserByName(String name)throws P3!JA)p6a
`pb=y}
HibernateException; D\^mh{q(
5BJn_<
publicint getUserCount()throws HibernateException; H Y~[/H+:
z"nMR_TTu
publicList getUserByPage(Page page)throws iNs@8<=$T
VS\| f'E
HibernateException; ;il+C!6zpf
*(s0X[-
} 00B,1Q HP
82)%`$yZw[
e'yw8U5E/
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>*/:"!u
java代码: }Ug$d>\
NR,R.N^[
:d6]rOpX
/*Created on 2005-7-15*/ j.!5&^;u4
package com.adt.dao.impl; EfB.K}b^
!hFzIp
import java.util.List; qZdA%
IyEfisOK?
import org.flyware.util.page.Page; :HM~!7e
.6!cHL3ln
import net.sf.hibernate.HibernateException; bt*
import net.sf.hibernate.Query; o@ m7@$7
\[G"/]J
import com.adt.dao.UserDAO; ;qO3m-(d
c|@OD3w2lM
/** f?r{Q
* @author Joa AJ>$`=
*/ ]VR79l
public class UserDAOImpl extends BaseDAOHibernateImpl Wf3{z
D~
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implements UserDAO { QFK'r\3pU
wV\7
/* (non-Javadoc) Mtl`A'KQ/K
* @see com.adt.dao.UserDAO#getUserByName AC\y|X8-
o5['5?i} /
(java.lang.String) HZ2f|Y|T
*/ :%gM
Xsb
publicList getUserByName(String name)throws $ y(Qdb
_FNW[V
HibernateException { A{dqB
String querySentence = "FROM user in class ykRd+H-t
`,O"^zR)z
com.adt.po.User WHERE user.name=:name"; VnqcpJ
Query query = getSession().createQuery 1+"d-`'Z2O
j115:f
(querySentence); 9K;g\? 3
query.setParameter("name", name); F~0iJnF
return query.list();
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} >;]S+^dXY
Hh%"
/* (non-Javadoc) p1[|5r5Day
* @see com.adt.dao.UserDAO#getUserCount()
!<HF764@`
*/ 1g,Ofr
publicint getUserCount()throws HibernateException { B}P!WRNmln
int count = 0; 1Vkb}A,'
String querySentence = "SELECT count(*) FROM [wk1p-hf
Y3#8]Z_"}O
user in class com.adt.po.User"; W9{i ~.zo
Query query = getSession().createQuery qu.AJ*
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(querySentence); uGn BlR$}
count = ((Integer)query.iterate().next XI:+EeM?
JC`;hY
()).intValue(); 2I3H?Lrx!m
return count; f*:N*cC
} 39m8iI%w[
vTo+jQs^
/* (non-Javadoc) bxPJ5oT
* @see com.adt.dao.UserDAO#getUserByPage S(Z\h_m(
WL|71?@C
(org.flyware.util.page.Page) :`K2?;DC8
*/ v-8{mK`9\
publicList getUserByPage(Page page)throws belBdxa{"
LN)yQ-
HibernateException { ~c55LlO>
String querySentence = "FROM user in class ~Y{]yBGoF
Lr20xm
com.adt.po.User"; 7L!}F;yT
Query query = getSession().createQuery 0$NzRPbH
nTw:BU4jd
(querySentence); Bp5%&T k
query.setFirstResult(page.getBeginIndex()) t<"`gM^|
.setMaxResults(page.getEveryPage()); m;nH
v
return query.list(); 9ei<ou_s
} QCG-CzJ9l
;dtA-EfOZ
} fLeHn,*,"
q,_EHPc
N?8nlrDQ
Q-A_ 8
iaQfxQP1w%
至此,一个完整的分页程序完成。前台的只需要调用 EiP N44(
@My
RcC
userManager.listUser(page)即可得到一个Page对象和结果集对象 &xvNR=K[`
E:O/=cT
的综合体,而传入的参数page对象则可以由前台传入,如果用 e\O625
\ KsKb0sM
webwork,甚至可以直接在配置文件中指定。 eA3NyL
l: kW|
下面给出一个webwork调用示例: B
qINU
java代码: xOr"3;^
O>I%O^
+3M1^:
/*Created on 2005-6-17*/ ?v-!`J>EF#
package com.adt.action.user; {u0sbb(
@\:@_}Z`_}
import java.util.List; PN=5ICT
c,]fw2
import org.apache.commons.logging.Log; yRDtPK"E-
import org.apache.commons.logging.LogFactory; O'(D:D?
import org.flyware.util.page.Page; s'd\"WaQV
6;@:/kl t
import com.adt.bo.Result; YE:5'@Z
import com.adt.service.UserService; J0YNzC4
import com.opensymphony.xwork.Action; \ [M4[Qlq
"rc QS
H
/** ,&s"f4Mft
* @author Joa RQu[FZT,
*/ 0'Qvis[kt
publicclass ListUser implementsAction{ dtjb(*x
82V;J 8T?
privatestaticfinal Log logger = LogFactory.getLog hD7vjg&Z
!HtW~8|:
(ListUser.class); oA:`=f%\
.
Y$xNLoP[
private UserService userService; =EH/~NGk
a[,p1}!_
private Page page; 5E 9R+N
pcQkJF
privateList users; jwuSne
{9) HB:
/* {%RwZ'
* (non-Javadoc) DGw*BN%`
* }IdkXAB.
* @see com.opensymphony.xwork.Action#execute() * bhb=~
*/ [jxh$}?P
publicString execute()throwsException{ ]GsI|se
Result result = userService.listUser(page); ay`R jT
page = result.getPage(); !aJ6Uf%R
users = result.getContent(); G8MLg #
return SUCCESS; Zlt,Us`
} iSfRo31
|oePB<N
/** \@T;/Pj{[
* @return Returns the page. sPl3JP&s
*/ {qU;>;(
public Page getPage(){ h0A%KL
return page; P)hGe3
} d/ @P;YN!
?5^DQ|Hg ^
/** b/\l\\$-
* @return Returns the users. ccx0aC3@I
*/ }AiF 7N0
publicList getUsers(){ 'geN
dx
return users; /%F,
} I>6zX
W&[-QM8
/** b`Jsu!?{
* @param page f]C^{Uk#
* The page to set. et(AO)uv6
*/ OB^j
b8
publicvoid setPage(Page page){ MUCes3YJH
this.page = page; (\wV)c9
} [M:<!QXw
ytV[x
/** Bt1v7M
* @param users CHjm7
* The users to set. ,w=u?
*/ 6\VZ6oS
publicvoid setUsers(List users){ eOfVBF<C2
this.users = users; -D1A
} JL<<EPC
F7]8*[u
/** Cy)QS{YX
* @param userService wSdiF-ue
* The userService to set. O*n@!ye
*/ 7<K=G2_:
publicvoid setUserService(UserService userService){ 9%0^fhrJ
this.userService = userService; KFaYn
} M~y}0Ik
} xJFcW+
1CJAFi>%D
aN6HO
:o~]d
>66
`hZ
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, znIS2{p/`
)wdd"*hv
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 5)0'$Xxqa0
~LP5hL
么只需要: %F}d'TPx
java代码: T&:~=
Um*&S.y
S0LaQ<9.
<?xml version="1.0"?> THgEHR0,}[
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork C0>L<*C
23a:q{R
1.0//EN" "http://www.opensymphony.com/xwork/xwork- |1e//*
}KNBqPo4B
1.0.dtd"> ZqjLZ9?q
: &~LPmJ
<xwork> $U)nrni
Pmd5P:n*,
<package name="user" extends="webwork- <7gv<N6BQf
"x0KiIoPk
interceptors"> ?N@[R];
ZG~d<kM&8s
<!-- The default interceptor stack name 9ESV[
.&8a ;Q?c
--> $ERiBALN:
<default-interceptor-ref :oiHf:
%&s4YD/{
name="myDefaultWebStack"/> {K:]dO
SDk^fTV8x
<action name="listUser" .*J /F$
PR,8c
class="com.adt.action.user.ListUser"> VtGZB3
<param _?eT[!oO8
aB`jFp-
name="page.everyPage">10</param> T#[#w*w/
<result WYkh'sv >
PY&mLux%
name="success">/user/user_list.jsp</result> m3&