Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 XU7to]'K
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 p7\LLJ y
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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 @*rMMy 4
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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 ;[o:VuTs
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。 \(LD<-a
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分页支持类: ]DnAW'm
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java代码: n]6'!Eo
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package com.javaeye.common.util; 7s^b@&Le
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import java.util.List; 3^KR{N p
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publicclass PaginationSupport { uWx<J3~q.
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publicfinalstaticint PAGESIZE = 30; L%H\|>k`
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privateint pageSize = PAGESIZE; Wm1dFf.>
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privateList items; F7'MoH
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privateint totalCount; =
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privateint[] indexes = newint[0]; Y;Nq (
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privateint startIndex = 0; HB#!Dv&'
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public PaginationSupport(List items, int .+(ED
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totalCount){ OM.-apzC
setPageSize(PAGESIZE); b
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setTotalCount(totalCount); ~5Fx[q
setItems(items); wYe;xk`>
setStartIndex(0); 'g<"@SS+
} <IIz-6*V
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public PaginationSupport(List items, int %V;*E]
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totalCount, int startIndex){ ;8=Bee4
setPageSize(PAGESIZE); <LZ#A@]71
setTotalCount(totalCount); 3` IR
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setItems(items); !hJ!ck]M
setStartIndex(startIndex); 6
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} @ddCVxd
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public PaginationSupport(List items, int K!AA4!eUzM
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totalCount, int pageSize, int startIndex){ uj)vh
setPageSize(pageSize); BZv:E?1z
setTotalCount(totalCount); u~,hTY(%
setItems(items); 5OPvy,e6
setStartIndex(startIndex); G5|nt#>
} #e =E
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publicList getItems(){ S['rTuk
return items; aAP86MHO
} s5v}S'uO{
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publicvoid setItems(List items){
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this.items = items; #"oLz"{
} i<$?rB!i<1
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publicint getPageSize(){ t"9r`0>
return pageSize; +9]t]Vrw
} i{9.bpp/
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publicvoid setPageSize(int pageSize){ ZUj1vf6I
this.pageSize = pageSize; \0Xq&CG=E
} -+i7T^@|
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publicint getTotalCount(){ c0l?+:0M
return totalCount; 16N|
} S
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publicvoid setTotalCount(int totalCount){ 'w1ll9O
if(totalCount > 0){ 'k}w|gNB
this.totalCount = totalCount; IR3+BDE)>
int count = totalCount / %qqCpg4
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pageSize; /F^
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if(totalCount % pageSize > 0) 8LF=l1=~
count++; %x;~o:
indexes = newint[count]; zrA3bWs
for(int i = 0; i < count; i++){ -1hCi!
indexes = pageSize * _J2?B?S/j
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} 9W-"mD;
}else{ i"+TKo-
this.totalCount = 0; ve"tbNL
} 'xG{q+jj'
}
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publicint[] getIndexes(){ ?.-+U~
return indexes; KbciRRf!k
} ,c`Wmp^AY
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publicvoid setIndexes(int[] indexes){ Kc@Sw{JR#7
this.indexes = indexes; ~-G_c=E?
} ZmkH55Cn
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publicint getStartIndex(){ ^Nds@MR{8'
return startIndex; F_ -Xx"
} 1Ke9H!_P
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publicvoid setStartIndex(int startIndex){ * >:<
if(totalCount <= 0) yK"HHdYTV
this.startIndex = 0; "9X!Ewm"P
elseif(startIndex >= totalCount) 0dsL%G~/N
this.startIndex = indexes RH7!3ye
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[indexes.length - 1]; oO7)7$|1
elseif(startIndex < 0) ang~_Ec.
this.startIndex = 0; }Q\+w,pJgN
else{ YUTh*`1k<
this.startIndex = indexes B7Zi|-F
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[startIndex / pageSize]; CRiqY_gBf
} e\-,e+
} AuM}L&`i^
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publicint getNextIndex(){ <Voct
int nextIndex = getStartIndex() + WuI$
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pageSize; n
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if(nextIndex >= totalCount) MO| Dwuaf
return getStartIndex(); CbxWK#aMmB
else _KT'W!7
return nextIndex; F|'u0JQ)$
} {,(iL8,^
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publicint getPreviousIndex(){ Yne1MBK
int previousIndex = getStartIndex() - ~gQYgv<7
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pageSize; 9pr.`w
if(previousIndex < 0) f;OB"p
return0; /<-=1XJI
else zK_P3rLsS
return previousIndex; z TPNQ0=|
} P0sAq7"
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} c/j+aj0.v
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抽象业务类 <dVJV?i;
java代码: Wl+spWqW
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/** AOwmPHEL
* Created on 2005-7-12 IAN={";p
*/ ([^f1;ncm
package com.javaeye.common.business; [}l 90 lP
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import java.io.Serializable; Jf#-OlEQ
import java.util.List; #W.vX=/*
@SaxM4
import org.hibernate.Criteria; ;n|%W,b-
import org.hibernate.HibernateException; &m\Uc
import org.hibernate.Session; oSjYp(h:
import org.hibernate.criterion.DetachedCriteria; 0ZLLbEfnPB
import org.hibernate.criterion.Projections; 4pelIoj
import ^K4?uABc
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org.springframework.orm.hibernate3.HibernateCallback; C(8!("tU
import ?<\2}1
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org.springframework.orm.hibernate3.support.HibernateDaoS to1r
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upport; Lp4F1H2t-
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import com.javaeye.common.util.PaginationSupport; p8?"}
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public abstract class AbstractManager extends ;i/? fw[h
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HibernateDaoSupport { KDV.ZSF7
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privateboolean cacheQueries = false; ""_G4{
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privateString queryCacheRegion; l]Ym)QP
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publicvoid setCacheQueries(boolean a<E9@
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cacheQueries){ -yBj7F|
this.cacheQueries = cacheQueries; h^1!8oOYD
} ^|hVFM2
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publicvoid setQueryCacheRegion(String pp7
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queryCacheRegion){ /;[x3}[
this.queryCacheRegion = c^puz2
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queryCacheRegion; G$QN_h,}
} Ho[]03
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publicvoid save(finalObject entity){ hsYE&Np_Q
getHibernateTemplate().save(entity); .=d40m
} PyK!Cyq
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publicvoid persist(finalObject entity){ BpX` 49
getHibernateTemplate().save(entity); fBz|-I:k
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} $e,r>tgD
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publicvoid update(finalObject entity){ cD)9EFo
getHibernateTemplate().update(entity); `
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} 2+C:Em0yI
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publicvoid delete(finalObject entity){ f4F%\ "
getHibernateTemplate().delete(entity); n6M #Xc'JA
}
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publicObject load(finalClass entity, Br42Qo2"T>
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finalSerializable id){ V\e1NS
return getHibernateTemplate().load ^,5%fl
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(entity, id); ue@W@pj
} iWFtb)3B
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publicObject get(finalClass entity, oR,zr
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finalSerializable id){ ;volBfv
return getHibernateTemplate().get }; M@JMu,
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(entity, id); $/@
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} !y>up+cRjl
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publicList findAll(finalClass entity){ g>w {{G
return getHibernateTemplate().find("from ".N{v1
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" + entity.getName()); Ht/#d6cQ
} aSxDfYN=R
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publicList findByNamedQuery(finalString 3hje
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namedQuery){ o2hZ=+w>
return getHibernateTemplate 7'Hh^0<
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().findByNamedQuery(namedQuery); ~Z*7:bPN!^
} u2`j\
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publicList findByNamedQuery(finalString query, +xsGa{`
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finalObject parameter){ j72mm!
return getHibernateTemplate VlSM/y5
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().findByNamedQuery(query, parameter); z 0zB&}
} )PYh./_2
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publicList findByNamedQuery(finalString query, v6[VdWOx5
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finalObject[] parameters){ UUZm]G+
return getHibernateTemplate p5w9X+G%
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().findByNamedQuery(query, parameters); 9^`cVjD5
} &,:!gYN
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publicList find(finalString query){ [Ob'E!;<
return getHibernateTemplate().find L+T7Ge
q
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(query); ?TIi0;h
} 72J=_d>+
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publicList find(finalString query, finalObject i+< v7?:`#
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parameter){ yJO Jw o^
return getHibernateTemplate().find $cwmfF2C
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(query, parameter); m|x_++3
} |`Yn'Mj8rm
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public PaginationSupport findPageByCriteria Ruq>+ }4
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(final DetachedCriteria detachedCriteria){ N;BuBm5K
return findPageByCriteria 1>Vq<z
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); T /IX(b'<
} K`uPPyv
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public PaginationSupport findPageByCriteria CR2.kuM0~
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(final DetachedCriteria detachedCriteria, finalint H\ E%.QIx
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startIndex){ *zDDi(@vtK
return findPageByCriteria M5d EZ
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(detachedCriteria, PaginationSupport.PAGESIZE, FwHqID_!:l
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startIndex); Tz.okCo]z
} j)@{_tv6;
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public PaginationSupport findPageByCriteria 9^N(s7s
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(final DetachedCriteria detachedCriteria, finalint Hg8
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pageSize, z7L+wNYwg
finalint startIndex){ !wfUD2K1
return(PaginationSupport) &+ PVY>q
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getHibernateTemplate().execute(new HibernateCallback(){ ydY 7 :D
publicObject doInHibernate $UK m[:7
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(Session session)throws HibernateException { `'EG7
Criteria criteria = qdKqc,R1{
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detachedCriteria.getExecutableCriteria(session); 4b`Fi@J\
int totalCount = 1q5S"=+W[
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((Integer) criteria.setProjection(Projections.rowCount vdB2T2F
$)PS#ND&
()).uniqueResult()).intValue(); |r?0!;bN0
criteria.setProjection PO0Od z
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(null); 6GVAR
List items = @2d9
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criteria.setFirstResult(startIndex).setMaxResults ?[>Y@we
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(pageSize).list(); %{cVG-<_iz
PaginationSupport ps = :V#xrH8R
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new PaginationSupport(items, totalCount, pageSize, iyr8*L\
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startIndex); 'NfsAE
return ps; 6-/W4L)?>
} ,3MHZPJ?k]
}, true); 6@FhDj2X
} On!+7is'
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public List findAllByCriteria(final DKem;_6OQ
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DetachedCriteria detachedCriteria){ p}/D{|xO
return(List) getHibernateTemplate (,+#H]L
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().execute(new HibernateCallback(){ tS3&&t
publicObject doInHibernate AT3HHQD
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(Session session)throws HibernateException { 3PRU
Criteria criteria = U*sQ5uq
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detachedCriteria.getExecutableCriteria(session); ebCS4&c
return criteria.list(); L1Yj9i
} =X[?d/[
}, true); !XI9evJw
} s!D2s2b9e
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public int getCountByCriteria(final !qlk-0&`
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DetachedCriteria detachedCriteria){ bVN?7D(
Integer count = (Integer) &{a#8sbf#c
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getHibernateTemplate().execute(new HibernateCallback(){ Xf7]+
publicObject doInHibernate nC??exc
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(Session session)throws HibernateException { oSy9Xw
Criteria criteria = Q$`uZ
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detachedCriteria.getExecutableCriteria(session); MzKl=G
return |G6'GTwZD
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criteria.setProjection(Projections.rowCount a+k3wzJ
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()).uniqueResult(); p}gA8o
} B|9XqQ EI
}, true); T<Zi67QC@
return count.intValue(); 5i'?oXL
} L5KcI
} KY%qzq,n
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用户在web层构造查询条件detachedCriteria,和可选的 E1Q#@*rX>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t&5 Ne ?
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PaginationSupport的实例ps。 OQ<;w
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ps.getItems()得到已分页好的结果集 wCv9VvF`
ps.getIndexes()得到分页索引的数组 u:W/6QS
ps.getTotalCount()得到总结果数 $*_79F2zN
ps.getStartIndex()当前分页索引 Ks(l :oUB
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 sVmqx^-
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ? }`mQ <~
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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(Qx3T?b
j*f\Z!EeZ
一下代码重构了。 uXUuA/O5-
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我把原本我的做法也提供出来供大家讨论吧: wr,+9uK
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首先,为了实现分页查询,我封装了一个Page类: >X"\+7bw
java代码: uocFOlU0n
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/*Created on 2005-4-14*/ e6{E(=R[M
package org.flyware.util.page; H`q[!5~8
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/** t pxk8Ys
* @author Joa JdWav!PYm
* m,]9\0GUd
*/ 8.IenU9
publicclass Page { ty%,T.@e
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/** imply if the page has previous page */ EaL>~:j
privateboolean hasPrePage;
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/** imply if the page has next page */ plJUQk
privateboolean hasNextPage; r/P}j4)b7
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/** the number of every page */ }&6:0l$4!
privateint everyPage; hK{<&T
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/** the total page number */ (#z6w#CU(
privateint totalPage; ^7;s4q
yO7#n0q
/** the number of current page */ :c8d([)$
privateint currentPage; a=9QwEZ
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/** the begin index of the records by the current &Ll&A@yU
G)Y,*.,
query */ uAoZ&8D6
privateint beginIndex; @^g~F&Ta
H ="I=}
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/** The default constructor */ X2:23j<
public Page(){ WlGT&m&2
d 79 2#Dc
} C'Y2kb
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/** construct the page by everyPage zE/\2F$
* @param everyPage 8`]yp7ueS
* */ DpT$19Q+
public Page(int everyPage){ p:0X3?IG3
this.everyPage = everyPage; _.BT%4
} :IfwhI)
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/** The whole constructor */ "Y- WY,H
public Page(boolean hasPrePage, boolean hasNextPage, qn |~YXn
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@tD (<*f+
int everyPage, int totalPage, m_`%#$s}
int currentPage, int beginIndex){ 'lu3BQvfh
this.hasPrePage = hasPrePage; )Z['=+s%
this.hasNextPage = hasNextPage; _G25$%/LU
this.everyPage = everyPage; E7aG&K
this.totalPage = totalPage; n"Bc2}{
this.currentPage = currentPage; :rjfAe=s
this.beginIndex = beginIndex; apfr>L3
} S)4p'cUwq
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/** _)~VKA]""
* @return ?~yJ7~3TS<
* Returns the beginIndex. 5wl;fL~e
*/ #5'&
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publicint getBeginIndex(){ %yk_(3a
return beginIndex; o[+t}hC[
} wArfnB&
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/** .sFN[>)
* @param beginIndex C4|OsC7J
* The beginIndex to set. P*VZ$bUe5@
*/ zZ<*
publicvoid setBeginIndex(int beginIndex){ Np r u
this.beginIndex = beginIndex; >'.: Acn
} rzLW@k
zEukEA^9`
/** N>]J$[j
* @return #k`gm)|
* Returns the currentPage. 8?YeaMIBB
*/ q(~|roKA(
publicint getCurrentPage(){ jI H^
return currentPage; jiLJiYMg
} "dvo@n|
hCd? Kti
/** VYO1qj
* @param currentPage lCl5#L9
* The currentPage to set. w&Gc#-B
*/ Qf}.= (
publicvoid setCurrentPage(int currentPage){ 8Gnf_lkI
this.currentPage = currentPage; \[^!
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} =6Gn?
/{
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/** V'MY+#
* @return X ,^([$
* Returns the everyPage. Pt/]Z<VL
*/ lI.oyR'
publicint getEveryPage(){ DX+zK'34
return everyPage; C_8_sbZ/
} Q>rr?L`
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/** >!a- "
* @param everyPage RtpV08s\
* The everyPage to set. %d(= >
*/ 8"ZS|^#
publicvoid setEveryPage(int everyPage){ .5}Gt>4XM
this.everyPage = everyPage; 57gt"f
} 4K?
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/** hh*('n>[
* @return , c{ckm
* Returns the hasNextPage. ?h%Jb^#9
*/ ctjQBWE
publicboolean getHasNextPage(){ &vn2u bauS
return hasNextPage; +`g&hO\W
} TB+k[UxB
k,k>w#&
/** g=@d!]Z~[
* @param hasNextPage ^+CHp(X
* The hasNextPage to set. ~!8j,Bqs+z
*/ QKlsBq
publicvoid setHasNextPage(boolean hasNextPage){ yRXWd*9
this.hasNextPage = hasNextPage; gkA_<,38
} +{V`{'
v~x4Y,m%
/** 0BhcXHt
* @return ]W`?0VwF
* Returns the hasPrePage. ,$>l[G;Bm
*/ LCtVM70
publicboolean getHasPrePage(){ _N^w5EBC]
return hasPrePage; tH.L_< N
} QeuM',6R
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/** @p
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* @param hasPrePage dr: x0>
* The hasPrePage to set. Xo/H+[;X
*/ cy;i1#1rO
publicvoid setHasPrePage(boolean hasPrePage){ s8>y&b.
this.hasPrePage = hasPrePage; $D !/v)3
} 2b^Fz0
w4
rqqd} kA
/** &0-oi Y
* @return Returns the totalPage. JcmJq
fR
* ~"SQwE|
*/ 09jE7g @X}
publicint getTotalPage(){ LR>s2zu-
return totalPage; !U m9ceK
} s hH2/.>
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/** tkr&Fs"t+
* @param totalPage @*Ry`)T
* The totalPage to set. /:(A9b-B
*/ t(uvc{K*
publicvoid setTotalPage(int totalPage){ }^&f {
this.totalPage = totalPage; PgT8
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} 111A e*U
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} AguE)I&m
Bps%>P~.
a{hc{
Hxgc9Fis
/r"<:+
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Hcu!bOQ
d8w3Oz54
个PageUtil,负责对Page对象进行构造: prz COw
java代码: m x |V)
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/*Created on 2005-4-14*/ `Y4K w
package org.flyware.util.page; 4Zwbu
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import org.apache.commons.logging.Log; (b<0=U
import org.apache.commons.logging.LogFactory; N\g=9o|Q
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/** j_N<aX
* @author Joa j7kX"nz
* kF~(B]W(
*/ k/wD@H N
publicclass PageUtil { qfE0J;e
cVL|kYVWT
privatestaticfinal Log logger = LogFactory.getLog |zpy!X 3
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(PageUtil.class); /u4RZ|&as
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/** 3rH}/`d4
* Use the origin page to create a new page @GQfBV|3
* @param page I\k<PglRA
* @param totalRecords jL"V0M]c
* @return s~A-qG>
*/ Lxv 4w
publicstatic Page createPage(Page page, int U\?D;ABQ%
49&i];:%7%
totalRecords){ +?o!"SJ
return createPage(page.getEveryPage(), uo]xC+^
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page.getCurrentPage(), totalRecords); >U{iof<
} /)Cfm1$ic
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/** T3{~f
* the basic page utils not including exception /h+ W L
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handler B=a+cT
* @param everyPage BA2"GJvfIA
* @param currentPage O?Bf (y
* @param totalRecords v7
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* @return page nXLz<wE
*/ ?IHt T3'Rt
publicstatic Page createPage(int everyPage, int WK`o3ayH-
znsQ/[
currentPage, int totalRecords){ w8 :[w
everyPage = getEveryPage(everyPage); %%s)D4sW
currentPage = getCurrentPage(currentPage); 9efey? z
int beginIndex = getBeginIndex(everyPage, >80k5$t
: x&R'wX-
currentPage); Gc`PO
int totalPage = getTotalPage(everyPage, H@1'El\9
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totalRecords); x:MwM?
boolean hasNextPage = hasNextPage(currentPage, Za{O9Qc?D|
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totalPage); Q/4-7
boolean hasPrePage = hasPrePage(currentPage); @c]KHWI
{S{ %KkAV
returnnew Page(hasPrePage, hasNextPage, rzAf {2
everyPage, totalPage, O>]i?
currentPage, BJux5Nh
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beginIndex); ?K[Y"*y2
} ay7\Ae]
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privatestaticint getEveryPage(int everyPage){ FE!jN-#
return everyPage == 0 ? 10 : everyPage; Ur
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} ;m7G8)I
TUnAsE/J&
privatestaticint getCurrentPage(int currentPage){ D#&9zR86F
return currentPage == 0 ? 1 : currentPage; LVB wWlJ
} spfW)v/T!
D wJ^ W&*
privatestaticint getBeginIndex(int everyPage, int #MA6eE'R
sWr;%<K
currentPage){ p6<JpW5@_
return(currentPage - 1) * everyPage; (NLw#)?
} D;0>-
{O2=K#J
privatestaticint getTotalPage(int everyPage, int +s}&'V^
q!:dZES
totalRecords){ Z8$BgP
int totalPage = 0; >SDQ@63E?
(Ut8pa+yX
if(totalRecords % everyPage == 0) toPbFU'
totalPage = totalRecords / everyPage; 7?whxi Qs
else -4Hb]#*2
totalPage = totalRecords / everyPage + 1 ; Q0R05*
S=r0tao,!v
return totalPage; TxPFl7,r
} &RZO\ZT
) 1AAL0F\B
privatestaticboolean hasPrePage(int currentPage){ F9j@KC(yg
return currentPage == 1 ? false : true; tC'E#2
} m~
ah!QM
bHG<B
privatestaticboolean hasNextPage(int currentPage, v-z%3x.f
Ih:Q}V#6
int totalPage){ dzOco)y
return currentPage == totalPage || totalPage == 1;( h0j
JW[6
^Rw
0 ? false : true; H}kZ;8
} / rc[HbNg.
bIiuna\
3UUdJh<~
} e|{R2z"^
X+]>pA
lZ-U/$od
S3Y.+. 0U
GmR3
a
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 /Ot3[B
@G2# Z
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 zE/l
wvq4 P
做法如下: j$q5m 24L
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ~wDXjn"U&
I0zx'x)F
的信息,和一个结果集List: qqw P4ceG
java代码: ,kJ7c;:i
>O\+ 9T@
+u
Iq]tqe
/*Created on 2005-6-13*/ !Sn|!:N4
package com.adt.bo; x\G%
v%qOW)].
import java.util.List; ! eZls
wU+r]SK@
import org.flyware.util.page.Page; 7G_<+rn
6HK1?
/** )=Z;H"_
* @author Joa s0' haU
*/ 32 i6j
publicclass Result { 5\pS8<RJ;
Xeq9Vs zg
private Page page; U}jGr=tu
ikc1,o
private List content; ~QbHp|g
kaCN^yQ
/** Ge`7`D>L
* The default constructor jlP*RX
*/ Sh!c]r>\Q
public Result(){ L4Jm8sy{
super(); HMF2sc$N
} \eKXsO"d
1 .+O2qB
/** }%Mdf6LS64
* The constructor using fields AT1cN1:4?
* R/v|ZvI
* @param page u&Ic
* @param content p*c(dkOe8
*/ by>%}#M
public Result(Page page, List content){ gttsxOgktH
this.page = page; h,Hr0^?
this.content = content; :o!Kz`J
} iKaX8c,zI
8s6[-F5
/** "?zWCH
* @return Returns the content. zj r($?
*/ 0E26J@jcZ7
publicList getContent(){ ]!AS%D`
return content; u9f^wn
} Sqn>L`Lz
ltuV2.$
/** Jai]z
* @return Returns the page. +=J$:/&U
*/ f DXK<v)
public Page getPage(){ v,}C~L3
return page; ZFtR#r(~41
} 4N,[Gs<7
*Vl#]81~
/** KhWy
* @param content >`03EsU
* The content to set. {nmu(EP
*/ G{: B'08
public void setContent(List content){ $Xwk8<
this.content = content; YxM\qy{Vr
} V5lUh#@TN&
iO*5ClB
/** tM"vIz 05
* @param page dQIF'==6
* The page to set. =7+%31
*/ >;Hx<FKxP
publicvoid setPage(Page page){ (X@\2M4@T#
this.page = page; 9!jF$
} I+
|uyc
} q+9^rQ
x,^-a
ZOfv\(iJ;
M@es8\&S.
X >7Pqn'
2. 编写业务逻辑接口,并实现它(UserManager, N-2#-poDe
'df@4} 9
UserManagerImpl) @\F7nhSfa
java代码: E}4{{{r
9mHCms
/UunWZ u%
/*Created on 2005-7-15*/ cV>?*9z0
package com.adt.service; p|-> z
1L::Qu%E
import net.sf.hibernate.HibernateException; :.AC%'S
3Y#
import org.flyware.util.page.Page; c<_1o!68
h
i!K-_Uy
import com.adt.bo.Result; *66EkCj
a.<XJ\
/** =*'yGB[x)
* @author Joa
;cf$u}+
*/ (KC08
publicinterface UserManager { fwt+$`n
?jMM@O`Nu
public Result listUser(Page page)throws !7\dr )
9QP=
HibernateException; h:bx0:O"
s;P _LaIp)
} }BS
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vfqXHc
unj
^?fsJ
D>jtz2y=D
Ch?yk^cY
java代码: iyCH)MA
x=rMjz-`_
EB&hgz&_
/*Created on 2005-7-15*/ Ijiw`\;
package com.adt.service.impl; 1^o})9
2n>mISy+
import java.util.List; !jl^__
.DR
I`B ZZ-
import net.sf.hibernate.HibernateException; W=
NX$=il
l1zPL3"u_^
import org.flyware.util.page.Page; *H/)S 5
import org.flyware.util.page.PageUtil; sB:e:PK
XC6 |<pru
import com.adt.bo.Result; I;jH'._k#
import com.adt.dao.UserDAO; br88b`L
import com.adt.exception.ObjectNotFoundException; :@&e~QP(
import com.adt.service.UserManager; W:<2" &7
,+BFpN'
/** *8qRdI9
* @author Joa RQ|K?^k
v
*/ 9u=]D> kb
publicclass UserManagerImpl implements UserManager { SLP$|E;
J",Cwk\
private UserDAO userDAO; ){/n7*#Th%
t_I-6`8o]
/** nZj&Ma7R
* @param userDAO The userDAO to set. pD P*
3
*/ kxe{HxM$Z
publicvoid setUserDAO(UserDAO userDAO){ $Rze[3
this.userDAO = userDAO; *RJD^hu
} A\ mSS
SKf;Fe
/* (non-Javadoc) ^K`PYai
* @see com.adt.service.UserManager#listUser L7 FFa:#
W{JR%Sq$
(org.flyware.util.page.Page) /tkV/
*/ .vmCKZ
public Result listUser(Page page)throws ^&F.T-( A
<AVWT+,
HibernateException, ObjectNotFoundException { }6u}?>S
int totalRecords = userDAO.getUserCount(); 'GW~~UhdW
if(totalRecords == 0) _Hq)@AI
throw new ObjectNotFoundException M| }?5NS
( q*/=u
("userNotExist"); FFwu$S6e
page = PageUtil.createPage(page, totalRecords); :p<:0W2!
List users = userDAO.getUserByPage(page); /3L4K
returnnew Result(page, users); 4UL"f<7 T
} l-IA Q!d
f
4K)Z
e
} BThrv$D}
#( 4)ps.
"JF
siuDg,uqK5
U>b.MIBX
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 <!W9EM
fCb&$oRr!
询,接下来编写UserDAO的代码: ]$)};8;7W
3. UserDAO 和 UserDAOImpl: 1iqgTi>
java代码: V:D?i#%,z
,!AYeVq
KdlUa^}D
/*Created on 2005-7-15*/ %MtaWZ
package com.adt.dao; :q1j?0{2N
!k'E
import java.util.List; ?)qm=mebY
0a?[@ -Sz
import org.flyware.util.page.Page; IH=%%AS
Ka{QjW!%d<
import net.sf.hibernate.HibernateException; =;8q`
o9D#d\G
/** nm|"9|/
* @author Joa 7'.6/U
*/ #)DDQ?D
publicinterface UserDAO extends BaseDAO { A9HgABhax
(ia+N/$u
publicList getUserByName(String name)throws eZpi+BRS6
r_^]5C\
HibernateException; coXm*X>z
A8nf"mRD:
publicint getUserCount()throws HibernateException; k~Y_%#_
/ubGa6N
publicList getUserByPage(Page page)throws jfR!M07|
(=53WbOh/t
HibernateException; cpq0'x\
]x_14$rk
} oe_,q&e
NUY sQO)
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>va9*pdJ
OYfP!,+bn
java代码: ui*CA^ Y
Ag]Hk%
q>a/',m
/*Created on 2005-7-15*/ hG/Z65`&
package com.adt.dao.impl; "Bn]-o|r
vdulrnGqL
import java.util.List; [+dTd2uZ<\
~:4Mf/Ca
import org.flyware.util.page.Page; oH
[-fF
g;nPF*(
import net.sf.hibernate.HibernateException; ?P2d
9b
import net.sf.hibernate.Query; `t#Ie*
4y9n,~Qgw
import com.adt.dao.UserDAO; l0wvWv*k
f;W>:`'
/** BjUz"69
* @author Joa y-7$HWn
*/ KMkX0+Ao
public class UserDAOImpl extends BaseDAOHibernateImpl j98>Jr\
u $T'#p1
implements UserDAO { /#4BUfY
f
A.S:eQvS%
/* (non-Javadoc) q1M16qv5
* @see com.adt.dao.UserDAO#getUserByName CY8=prC
HuL9' M
(java.lang.String) L5>.ku=T
*/ gY@$g
publicList getUserByName(String name)throws KA{Y*m^7
\tg}K0E?R5
HibernateException { ^p7Er!
String querySentence = "FROM user in class e,0Gc-X[B
cW, 6MAQo
com.adt.po.User WHERE user.name=:name"; }"9jCxXL
Query query = getSession().createQuery W-U[7n
$30lNZK1m8
(querySentence); uw&'=G6v
query.setParameter("name", name); @MGc_"b
return query.list(); g~=#8nJ
} I'RhA\`
@Nt$B'+S&
/* (non-Javadoc) #%tN2cFDN
* @see com.adt.dao.UserDAO#getUserCount() k*xgF[T
8
*/ ?IV3"\5
publicint getUserCount()throws HibernateException { bQ2 '*T
int count = 0; uYwJ[1C
String querySentence = "SELECT count(*) FROM A&QO]8
1=%\4\
user in class com.adt.po.User"; mH} 1Zy
Query query = getSession().createQuery A
ptzBs/
e?~6HP^%.
(querySentence); <P1sK/IZb
count = ((Integer)query.iterate().next i;B)@op.#
[2cG 7A
()).intValue(); sHulaX{
return count; /\M3O
} Z:}d\~`x$%
"# mr?h_
/* (non-Javadoc) Li_ a|dI
* @see com.adt.dao.UserDAO#getUserByPage x5}Ru0Z
m48m5>
(org.flyware.util.page.Page) 5*pCb,z>q
*/ ,.<l^sj5
publicList getUserByPage(Page page)throws ;M"JN:J8
J Covk1
HibernateException { 5rpTR
String querySentence = "FROM user in class cUz7F
MRdZ '
com.adt.po.User"; pTlNJ!U>
Query query = getSession().createQuery Ey!+rq}
k:0HsN!F9
(querySentence); \{[Gdj`
query.setFirstResult(page.getBeginIndex()) `8%2F}x}qD
.setMaxResults(page.getEveryPage()); ca1A9fvo
return query.list(); AA$-Lx(UJk
} dRXF5Ox5K}
1x#Z}XG
} hqVFb.6[
{?' DZR s
P*6B+8h"5g
D?3^>h
Yvu!Q
至此,一个完整的分页程序完成。前台的只需要调用 \j]i"LpWb
}?=$?3W
userManager.listUser(page)即可得到一个Page对象和结果集对象 gUB%6v G\I
-&*
4~
的综合体,而传入的参数page对象则可以由前台传入,如果用 SablF2doa
BV X6
webwork,甚至可以直接在配置文件中指定。 C-abc+/
;X
]+r$_
下面给出一个webwork调用示例: dk9'C
java代码: }Q?,O
@e_ bG@
j\D_Z{m2
/*Created on 2005-6-17*/ |BGQ|7DyG
package com.adt.action.user; !giL~}j(R
y pv~F
import java.util.List; OFTyN^([@
kw>W5tNpf:
import org.apache.commons.logging.Log; I=)u:l c
import org.apache.commons.logging.LogFactory; 0[JJ
import org.flyware.util.page.Page; p] V
[Az<E3H"
import com.adt.bo.Result; CD'.bFO^+T
import com.adt.service.UserService; *eAsA(;
import com.opensymphony.xwork.Action; Yp1;5Bbp
e:E:"elr]
/** sF$$S/b
* @author Joa B6&;nU>;
*/ %EuJ~;x(Mg
publicclass ListUser implementsAction{ qJ b9JL$s
B'OUT2cgB
privatestaticfinal Log logger = LogFactory.getLog ruG5~dm>
i"~J -{d}
(ListUser.class); ]CD
'Tni;
private UserService userService; WKib$(%f6
@Q;%hb
private Page page; P5Y:c@u2
o.ntzN
privateList users; P".CZyI-i
TzT(aWP"
/* v"VpE`z1#
* (non-Javadoc) }j^asuf~c
* ?CgqHmf\\(
* @see com.opensymphony.xwork.Action#execute() J|-X?V;ZW
*/ x78`dX
publicString execute()throwsException{ *UVo>;
Result result = userService.listUser(page); [=[>1<L>
page = result.getPage(); 59;p|
users = result.getContent(); diF-`~
return SUCCESS; X!,2/WT
} roDE?7x1
0drt,k
/** AM4lAq_
* @return Returns the page. 18ApHp
*/ h\#\hx
public Page getPage(){ Y[l*>}:w
return page; WdEVT,jjh
} 038|>l-9[
:C*7DS
/** WZ\bm$
* @return Returns the users. q#RUL!WF7U
*/ lxIoP
publicList getUsers(){ s9R#rwIc
return users; J!40`8i
} 9K]Li\
*E*=
;BG
/** 'aYUF&GG
* @param page _Mi`]VSq9
* The page to set. ]}t6V]`Q
*/ $#VE C0
publicvoid setPage(Page page){ .ME>ICA
this.page = page; a<c]N:1
} dux.Z9X?
xeo5)
/** e
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* @param users w;@NYMK)
* The users to set. cEI
"
*/ (_h=|VjK(I
publicvoid setUsers(List users){ 5bKBVkJ'
this.users = users; wKxw|Fpn
} LH7m >/LJr
F|+Qi BO
/** =lB+GS%
* @param userService <'n'>@
* The userService to set. )ry7a
.39b
*/ US5 ]@!
publicvoid setUserService(UserService userService){ "DN0|%`M/
this.userService = userService; SlU?,)J}
} d 8YP<"V&
} =<yMB d\
~s3X&!#
L|B/'
Q=YIAGK
*0vq+C
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, H(L.k;B
?4k/V6n@y
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 WP*xu-(:
/\L-y,>X
么只需要: ~e|RVY,
java代码: }W2FF
;Gc,-BDFw
/g/]Q^
<?xml version="1.0"?> kq| r6uE
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork S2y_5XJ<D
tx` Z?K[
1.0//EN" "http://www.opensymphony.com/xwork/xwork- w)C/EHF
JRti2Mu
1.0.dtd"> R[#Np`z
{5 V@O_*{
<xwork> |7Dc7p"D
QZwUv<*
<package name="user" extends="webwork- eILdq*
tQR qQ
interceptors"> hn`yc7<}(u
%mqep5n(
<!-- The default interceptor stack name ]>vC.iYp
wh Hp}r
--> %#go9H(K
<default-interceptor-ref _HMQx_e0YM
+56N}MAs
name="myDefaultWebStack"/> -!@]z2uU
u~O9"-m !V
<action name="listUser" ;AH8/M B9
.-Z=Aa>
class="com.adt.action.user.ListUser"> 8SZZ_tS3r
<param $^TxLv
g5&ZXA
name="page.everyPage">10</param> p>ba6BDJT
<result 4h*c{do
'hGUsi
name="success">/user/user_list.jsp</result> oV/:T\Qn=
</action> H*.v*ro9_
K#%@4]jO3
</package> C.|.0^5
=67ab_V
</xwork> &0*7]Wo*
]D.}
/g
m~I@q
[
p=XEMVqm
(X?HuWTm
"cZ ){w
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 QbJE+m5
xcQD]"
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 *Uw" `l
gB<1;_KW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 9^?2{aP%
SuR+Vv
d53Eu`QW?
w#d7
!U7}?i&H
我写的一个用于分页的类,用了泛型了,hoho mI,a2wqi
rff_=(?i
java代码: SpO%nZ";g8
01n7ua*XX
]."t
package com.intokr.util; {i<L<Y(3
,Mr_F^|
import java.util.List; .: Zw6
lyS`X
/** Fy*t[>
* 用于分页的类<br> ~v@.YJoZ4Z
* 可以用于传递查询的结果也可以用于传送查询的参数<br> wzj:PS
* :u,Ji9
u
* @version 0.01 h1~/zM/`
* @author cheng 7](aPm8
*/ \zJb}NbnT
public class Paginator<E> { ms&6N']
privateint count = 0; // 总记录数 r0Zj'F_e
privateint p = 1; // 页编号 C14"lB.
privateint num = 20; // 每页的记录数 3o2x&v
privateList<E> results = null; // 结果 kmg/hNtN
\IhHbcF`d
/** (j(hr'f
* 结果总数 -]Ny-[P
*/ yJ:rry
publicint getCount(){ F Jp<J
return count; 7 \AoMk}
} m;J'y2h =$
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publicvoid setCount(int count){ 6{w'q&LYcE
this.count = count; \;+TZ1i_
} 0}`0!Kv
WR9-HPF
/** }vb.>hy
* 本结果所在的页码,从1开始 P\y ZcL
* 0Of6$`
* @return Returns the pageNo. C';Dc4j
*/ 2c'<rkA
publicint getP(){ *&z!y/
return p; RGLJaEl !
} E#E&z (G2
^U6VJ(58P
/** gg.lajX
* if(p<=0) p=1 U]&/F{3
im
* K1=j7
* @param p V$_.&S?(Y
*/ X"V)oC
publicvoid setP(int p){ q8)wAl
if(p <= 0) o]eG+i6g]
p = 1; 19:1n]*X<
this.p = p; ?jU 3%"
} OWp`Wat
#bS}?fj
/** _Qq lOc9
* 每页记录数量 v\g1w&PN
*/ 9aYVbq""
publicint getNum(){ k/M{2Po+
return num; !TN)6e7`
} UJuz
BxiR0snf0q
/** DFbhy
* if(num<1) num=1 sVH
w\_F$
*/ \.?'y71
publicvoid setNum(int num){ .IsOU
if(num < 1) U1D;O}z~
num = 1; g'9~T8i& ^
this.num = num; v=daafO
} ,=[r6k<
y:Ag mr,S
/** Ih[k{p
* 获得总页数 ltv~Kh
*/ E_0i9
publicint getPageNum(){ ~i]4~bkH2
return(count - 1) / num + 1; sw50lId
} YlXqj\a
`[h&Q0Du6
/** {Q)sR*d
* 获得本页的开始编号,为 (p-1)*num+1 W!|l_/L'
*/ %v0;1m
publicint getStart(){ ";upu
return(p - 1) * num + 1; xg4wtfAbS
} |9[)-C~N7
4j(*%da
/** 5^{ I}Q
* @return Returns the results. <.{OIIuk
*/ T[-Tqi NT
publicList<E> getResults(){ $,o@&QT?AT
return results; _z\qtl~3
} DG,m;vg+
'8LHX6FXK
public void setResults(List<E> results){ F5H]$AjW
this.results = results; Q6p75$SVq
} [xXV5 JU
A~;.9{6J[t
public String toString(){ +E+I.}sOB
StringBuilder buff = new StringBuilder ([ A%>u>h
Y pvFv-
(); /PpZ6ne~[
buff.append("{"); [;#^h/5E
buff.append("count:").append(count); xs?]DJj
buff.append(",p:").append(p); )h,}v()qc#
buff.append(",nump:").append(num); bRJ]avR
buff.append(",results:").append 6&btAwvOHx
>}r
1A
(results); lr[&*v?h
buff.append("}"); (\4YBaGd
return buff.toString(); \*#E4`Y
} &-KQ
m20n
{~V_6wY g
} X=VaBy4#
4rypT-%^ ;
GXR7Ug}k