Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 .J @mpJdY
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 `.~S/$a.&
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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 \l3z<\
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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 LD?\gK"
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分页支持类: S`b!sT-sD
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java代码: dB#c$1
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package com.javaeye.common.util; cjGN=|`u
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import java.util.List; 5
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publicclass PaginationSupport { @.k^ 8hc
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publicfinalstaticint PAGESIZE = 30; F~rl24F
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privateint pageSize = PAGESIZE; v36Z*I6)5
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privateList items; V+lS\E.
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privateint totalCount; o58c!44
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privateint[] indexes = newint[0]; +$>aT(q
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privateint startIndex = 0; lcpiCZ
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public PaginationSupport(List items, int a"O;DYh
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totalCount){ l0t(t*[Mj
setPageSize(PAGESIZE); B<.\^fuS
setTotalCount(totalCount); I<<1mEk
setItems(items); *K?UWi#$
setStartIndex(0); d:A'|;']
} 2x|FVp
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public PaginationSupport(List items, int cQd?,B3#F
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totalCount, int startIndex){ Ug0c0z!b
setPageSize(PAGESIZE); ,{(XT7hr
setTotalCount(totalCount); V,& OO
setItems(items); e#}Fm;|d
setStartIndex(startIndex); -\%5aXr
} / s Apj
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public PaginationSupport(List items, int F" M/gy
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totalCount, int pageSize, int startIndex){ 8#,_%<?UVy
setPageSize(pageSize); Au)~"N~p?
setTotalCount(totalCount); ^A\(M%*F
setItems(items); M(\{U"%@?
setStartIndex(startIndex); |XQ_4{
} Pz
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publicList getItems(){ u~FVI
return items; ?9eiT:2
} zNo"P[J8
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publicvoid setItems(List items){ #Q=c.AL{
this.items = items; /G]/zlUE
} L|(U%$
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publicint getPageSize(){ <?DI!~
return pageSize; 4=y&}3om(0
} UB8n,+R
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publicvoid setPageSize(int pageSize){ An?#B4:
this.pageSize = pageSize; 2Rwd\e.z
} `) ],FE*:
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publicint getTotalCount(){ E&t8nlTx
return totalCount; :,$"Gk
} E^{!B]/oP
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publicvoid setTotalCount(int totalCount){ Zi\ex\ )5
if(totalCount > 0){ >y#qn9rV1
this.totalCount = totalCount; pih 0ME}z
int count = totalCount / ~W4SFp
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pageSize; 2$t%2>1>@
if(totalCount % pageSize > 0) Gi@c`lRd1
count++; Jwj=a1I 53
indexes = newint[count]; |Go$z3bx
for(int i = 0; i < count; i++){ aTH$+f1?Q
indexes = pageSize * !RwhVaSh
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} WH7UJCQ
}else{ t3^`:T\
this.totalCount = 0; q&6|uV])H
} R@ Gll60
} iY,oaC~?"N
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publicint[] getIndexes(){ j}tGcFwvSN
return indexes; ^ )!eiM
} '+iLW~
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publicvoid setIndexes(int[] indexes){ f2Xn !]o
this.indexes = indexes; ~@@$-,}X
} Xnh&Kyz`v
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publicint getStartIndex(){ <|G!Qn?2-
return startIndex; {w"Cr0F,
} EvY^]M_U
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publicvoid setStartIndex(int startIndex){ {<}Hut:a
if(totalCount <= 0) \WdSj
this.startIndex = 0; x\:KfYr4Y;
elseif(startIndex >= totalCount) br k*;
this.startIndex = indexes +`mI\+y,
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[indexes.length - 1]; :w|=o9J
elseif(startIndex < 0) Ets6tM`
this.startIndex = 0; bF,.6iKI
else{ 't*]6^
this.startIndex = indexes -U9C{q?h
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[startIndex / pageSize]; o>yXEg
} }1Mf0S
} d,
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publicint getNextIndex(){ ?Oy0p8
int nextIndex = getStartIndex() + cCx{
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pageSize; 7D 3-/_ v
if(nextIndex >= totalCount) >/}p{Tj
return getStartIndex(); s!MD8ia
else kj4=Q\Rfm
return nextIndex; <*u^8lCA
} @;hdZLG]`&
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publicint getPreviousIndex(){ i<tJG{A=
int previousIndex = getStartIndex() - !SnLvW89Z
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pageSize; (64es)B}"
if(previousIndex < 0) {5%d#|?
return0; =_@) KWeX$
else 8)"lCIf
return previousIndex; [^/a`Kda8
} 4qsxlN>4O
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} *0V'rH)
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抽象业务类 >mEfd=p
java代码: Zvfy%k
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/** +IjBeQ?
* Created on 2005-7-12 M ]O4
*/ gsa@ci
package com.javaeye.common.business; G'dN<Nw6
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import java.io.Serializable; NNE(jJ`/
import java.util.List; u.?jW vcv
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import org.hibernate.Criteria; `/!FZh<
import org.hibernate.HibernateException; gLZJQubz
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import org.hibernate.Session; utC^wA5U~
import org.hibernate.criterion.DetachedCriteria; 7&%#bMnw
import org.hibernate.criterion.Projections; f:~$x
import C6@*l~j
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org.springframework.orm.hibernate3.HibernateCallback; L8NZU*"
import FDGG$z?>m
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org.springframework.orm.hibernate3.support.HibernateDaoS s&$e}yxVO
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upport; jWh)bsqI!
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import com.javaeye.common.util.PaginationSupport; [EZ=t k
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public abstract class AbstractManager extends f4+wP/n&
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HibernateDaoSupport { eT(X Ri0
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privateboolean cacheQueries = false; a{rUk%x
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privateString queryCacheRegion; MpJ<. |h
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publicvoid setCacheQueries(boolean UK,sMKbl1
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cacheQueries){ '^[+]
this.cacheQueries = cacheQueries; w8J8III\~
} IJDbm}:/e
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publicvoid setQueryCacheRegion(String EdSUBoWF}
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queryCacheRegion){ mieyL9*n7
this.queryCacheRegion = hJir_=
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queryCacheRegion; ]\L+]+u~
} ];b+f@
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publicvoid save(finalObject entity){ 3=} P l,
getHibernateTemplate().save(entity); }Ujgd2(U
} ('\sUZ+5
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publicvoid persist(finalObject entity){ b7T;6\[m
getHibernateTemplate().save(entity); du#f_|xG
} Rr[Wka9[
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publicvoid update(finalObject entity){ owVks-/
getHibernateTemplate().update(entity); $%
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} . n)R@&9
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publicvoid delete(finalObject entity){ Z'}%Mkm`i}
getHibernateTemplate().delete(entity); ozl!vf# kv
} +o"CMI
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publicObject load(finalClass entity, D. x8=|;
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finalSerializable id){ e+4Eiv
return getHibernateTemplate().load Z5)v
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(entity, id); 9d(#/n
} C+5X8
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publicObject get(finalClass entity, VEn3b
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finalSerializable id){ {d0-.
return getHibernateTemplate().get nLv~)IQ}:
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(entity, id); cx&\oP
} n4}e!
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publicList findAll(finalClass entity){ z5Tsu1c
return getHibernateTemplate().find("from SBDGms
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" + entity.getName()); _G'A]O/BZD
} x#zj0vI-8
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publicList findByNamedQuery(finalString uGqeT#dP
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namedQuery){ i1m>|[@k
return getHibernateTemplate ^3H:I8gRCl
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().findByNamedQuery(namedQuery); T{"Ur:p
} n~}[/ly
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publicList findByNamedQuery(finalString query, W3\E;C-g0
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finalObject parameter){ $ Y^0l
return getHibernateTemplate ) jvI Nb
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().findByNamedQuery(query, parameter); hiA\~}sl n
} UL>2gl4s/
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publicList findByNamedQuery(finalString query, XuHR
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finalObject[] parameters){ %N`_g' r!
return getHibernateTemplate 6akI5\b
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().findByNamedQuery(query, parameters); *FZav2]-
} 4#]g852
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publicList find(finalString query){ d,Oagx
return getHibernateTemplate().find WVOj;c
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(query); ]7yxXg
} 3(,m(+J[S
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publicList find(finalString query, finalObject udBIEW,`
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parameter){ 'g'RXC}D>
return getHibernateTemplate().find .s!0S-RkC
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(query, parameter); gTOx|bx
} m6$&yKQ-=h
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public PaginationSupport findPageByCriteria :D-D+x
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(final DetachedCriteria detachedCriteria){ bR~(Ry`
return findPageByCriteria r Dlu&
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); UntFkoO
} {Q_GJ
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public PaginationSupport findPageByCriteria Qzo -Yw`=
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(final DetachedCriteria detachedCriteria, finalint I}0? d
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startIndex){ _5~|z$GW
return findPageByCriteria K@g
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(detachedCriteria, PaginationSupport.PAGESIZE, 5p S$rf
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startIndex); 8 sc2r
} H@$K/
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public PaginationSupport findPageByCriteria yI#qkl-
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(final DetachedCriteria detachedCriteria, finalint E QU@';~8
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pageSize, zuW4gJ
finalint startIndex){ YI"!&a'yj
return(PaginationSupport) X';qcn_^
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getHibernateTemplate().execute(new HibernateCallback(){ jQ%1lQ#R)
publicObject doInHibernate "5
~{
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(Session session)throws HibernateException { A:GqR;;"x>
Criteria criteria = HJ]e%og
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detachedCriteria.getExecutableCriteria(session); +ZW>JjP*
int totalCount = iQ8{N:58DN
d v[.u{#tP
((Integer) criteria.setProjection(Projections.rowCount f:&JKB)N
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()).uniqueResult()).intValue(); %aK[Yvo6
criteria.setProjection ol/@)k^s>
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(null); L
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List items = 'h'pM#D
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criteria.setFirstResult(startIndex).setMaxResults ,\P|%yv
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(pageSize).list(); %H"
PaginationSupport ps = YtSYe%
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new PaginationSupport(items, totalCount, pageSize, o4EY2
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startIndex); 9c k"JMla
return ps; Dbj?l;'1
}
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}, true); nA("
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} qp6'n&^&
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public List findAllByCriteria(final U2<q dknB
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DetachedCriteria detachedCriteria){
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return(List) getHibernateTemplate [#Gu?L_W
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().execute(new HibernateCallback(){ qg`ae
publicObject doInHibernate Zn
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(Session session)throws HibernateException { ]J!#"m-]
Criteria criteria = {Hl(t$3V`
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detachedCriteria.getExecutableCriteria(session); h~Z &L2V
return criteria.list(); zc;kNkV#1Y
} 1)
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}, true); V
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} f['lY1#V1
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public int getCountByCriteria(final Eze w@*(
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DetachedCriteria detachedCriteria){ [u K,.G
Integer count = (Integer) [9Rh" H;h
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getHibernateTemplate().execute(new HibernateCallback(){ wk8fa
publicObject doInHibernate zNKB'hsK
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(Session session)throws HibernateException { Ayqs~&{
Criteria criteria = uIO,9> ee
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detachedCriteria.getExecutableCriteria(session); zzI,iEG
return 9M9Fif.
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criteria.setProjection(Projections.rowCount lg$aRqI29
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()).uniqueResult(); M$ieM[_T
} *'aJO}$
}, true); +,)k@OI
return count.intValue(); ll$mRC
} uuFQTx))
} WeH_1$n5
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用户在web层构造查询条件detachedCriteria,和可选的 gE@Pb
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 FN!?o:|(
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PaginationSupport的实例ps。 eza"<uBr
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ps.getItems()得到已分页好的结果集 7lwI]/ZH*
ps.getIndexes()得到分页索引的数组 l6WEx
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ps.getTotalCount()得到总结果数 DIQ30(MS
ps.getStartIndex()当前分页索引 DU"Gz!X]Jd
ps.getNextIndex()下一页索引 k&t.(r\
ps.getPreviousIndex()上一页索引 NkBvN\CQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 w]T_%mdk
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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 <$A/ ('
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一下代码重构了。 0H +nVR
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我把原本我的做法也提供出来供大家讨论吧: _$IWr)8f
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首先,为了实现分页查询,我封装了一个Page类: C,>n
java代码: 8NNh8k#6
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/*Created on 2005-4-14*/ xV14Y9
package org.flyware.util.page; A ?V-Sz#
v
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/** {RI^zNgs[
* @author Joa -;"A\2_y
* N@<-R<s^
*/ $RI$VyAjD
publicclass Page { _ti^i\8~
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/** imply if the page has previous page */ vYXh WqL~
privateboolean hasPrePage; td\gk
xE--)=<$
/** imply if the page has next page */ y7#+VF`xf
privateboolean hasNextPage; k3B_M9>!
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/** the number of every page */ Y}.f&rLe
privateint everyPage; 4j'rbbs/
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/** the total page number */ 5 8;OTDR!
privateint totalPage; CfrO1i F
& }j;SK5
/** the number of current page */ (HeSL),1
privateint currentPage; Pr%KcR ;
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/** the begin index of the records by the current Gb[J3:.
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query */ ~0-)S@
privateint beginIndex; pl,XS6mB
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/** The default constructor */ 9&^5!R8
public Page(){ IpzU=+h
m$_l{|4z
} jc:=Pe!E
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/** construct the page by everyPage 1l^[%0
* @param everyPage >{Mv+
* */ xgNV0;g,
public Page(int everyPage){ U5cbO{\3I
this.everyPage = everyPage; jb/C\2U4)
} /\Xe'&
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/** The whole constructor */ !JDuVqW
public Page(boolean hasPrePage, boolean hasNextPage, H[pvC=O=
NzhWGr_x'
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int everyPage, int totalPage, q%A>q;l:
int currentPage, int beginIndex){ $1s>efP-
this.hasPrePage = hasPrePage; Rd;t}E$
this.hasNextPage = hasNextPage; PW"?*~&
this.everyPage = everyPage; =$^}"}$
this.totalPage = totalPage;
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this.currentPage = currentPage; ZK2&l8
this.beginIndex = beginIndex; Fpn'0&~-fi
} J]S6%omp>
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/** 6yYd~|T.Fl
* @return n?q+:P
* Returns the beginIndex. s`,g4ce`
*/ {s6#h #U
publicint getBeginIndex(){ }NV<k
return beginIndex; zU0JwZi
} 86qQ"=v
dn42'(p@G
/** Ik5-ooZ&{
* @param beginIndex a.O"I3{?h
* The beginIndex to set. (<OmYnm
*/ T51oNO%^
publicvoid setBeginIndex(int beginIndex){ I-J%yutB
this.beginIndex = beginIndex; EXW?)_pg
} M,{; xf
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/** Ae^4
* @return >U4bK^/Bp
* Returns the currentPage. P$ b5o
*/ fyx Q{J
publicint getCurrentPage(){ NX;{L#lQ
return currentPage; BjjuZN&
} w}07u5
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/** MD4mh2
* @param currentPage yVPFH~1@\
* The currentPage to set. WoSKN7*
*/ hD,^mru
publicvoid setCurrentPage(int currentPage){ hOIg7=v
this.currentPage = currentPage; Rdd9JJsVd
} Fo
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/** m^/>C-&C
* @return *z~J ]
* Returns the everyPage. 4 #lLC-k
*/ y^{4}^u-^
publicint getEveryPage(){ \j
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return everyPage; 0U.Ld:
} @JP6F[d
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/** %A&g-4(
* @param everyPage NLgeBLB
* The everyPage to set. > -fXn
*/ `C6,**`R$k
publicvoid setEveryPage(int everyPage){ K_N`My
this.everyPage = everyPage; 9Y2(.~w6X
} F[v^43-^_
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/** ecp0 hG`%
* @return K TE*Du
* Returns the hasNextPage. >u
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*/ >Bm>/%2
publicboolean getHasNextPage(){ $'a]lR
return hasNextPage; +}-cvM/*
} FklO#+<:
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/** n2F*a
* @param hasNextPage AMK3I`=8WO
* The hasNextPage to set. N=8CVI
*/ p1z^i(
publicvoid setHasNextPage(boolean hasNextPage){ ,~K4+
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this.hasNextPage = hasNextPage; k.Z?BNP
} !) d
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/** G%%F6)W
* @return @$!"}xDR'
* Returns the hasPrePage. 9*?YES'6
*/ c8cGIAOY)
publicboolean getHasPrePage(){ UyNP:q:
return hasPrePage; .e S* F
} t$Ua&w
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/** K<u~[^R
* @param hasPrePage _xP@kN~
* The hasPrePage to set. Tl^)O^/
*/ 4)N~*+~\h
publicvoid setHasPrePage(boolean hasPrePage){ g-+/zEOUS
this.hasPrePage = hasPrePage; kw1Lm1C
} LyNur8 Zi
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/** kN vNV(4
* @return Returns the totalPage. v[m1R'
* *b1NVN$
*/ B8V85R
publicint getTotalPage(){ 6y@o[=m
return totalPage; DsiyN:o'+
} q1%xk=8
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/** "9H#pj -
* @param totalPage JCITIjD7=
* The totalPage to set. CT{X$N
*/ f%STkL)
publicvoid setTotalPage(int totalPage){ IS!]!s'EI
this.totalPage = totalPage; Lb2/ Te*
} *>j4tA{b@v
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} n]wZ7z
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j 2Jew
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 A^ry|4`3(
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个PageUtil,负责对Page对象进行构造: m] IN-'
java代码: <UJ5n) }"\
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/*Created on 2005-4-14*/ *>Zq79TG
package org.flyware.util.page; XZPq4(,9}
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import org.apache.commons.logging.Log; d!q)FRzi
import org.apache.commons.logging.LogFactory; wQ9fPOm
mY]R~:
/** DzvGR)>/
* @author Joa )XD$YI
* bd.t|A
*/ cU=EXyP%
publicclass PageUtil { HBgt!D0MZ
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privatestaticfinal Log logger = LogFactory.getLog Y<`uq'V
S
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(PageUtil.class); ^G(+sb[t
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/** uTUkRqtD!
* Use the origin page to create a new page EXbhyg
* @param page q^kOyA.
* @param totalRecords Aj2yAg
* @return
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*/ l,M?
publicstatic Page createPage(Page page, int kR(hUc1O
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totalRecords){ jQ?6I1o
return createPage(page.getEveryPage(), I =yy
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q \\52:\
page.getCurrentPage(), totalRecords); H9T'{R*FC
} X9n},}bJ"
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/** |=4imM7
* the basic page utils not including exception `Jon^&^;|
2UjQ!g`
handler *.NVc
* @param everyPage Yf,U2A\
* @param currentPage Y+#VzIZw
* @param totalRecords _n_|skG
* @return page .
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*/ GbZqLZ0
publicstatic Page createPage(int everyPage, int pWXoJ0N
aUX.4#|%
currentPage, int totalRecords){ FOd)zU*L2
everyPage = getEveryPage(everyPage); =P<7tsSuoK
currentPage = getCurrentPage(currentPage); &p#.m"Oon
int beginIndex = getBeginIndex(everyPage, N[AX]gOJ
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currentPage); ibskce{H
int totalPage = getTotalPage(everyPage, (Puag*
RI
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totalRecords); -XtDGNHF
boolean hasNextPage = hasNextPage(currentPage, ,XNz.+Ov
ue{0X\[P<
totalPage); r%~/y
boolean hasPrePage = hasPrePage(currentPage); (Y%pk76d
re\&'%~K
returnnew Page(hasPrePage, hasNextPage, Vi1=
E])
everyPage, totalPage, x*uQBNf=
currentPage, p+bT{:
=h9&`iwiu
beginIndex); ns,qj}#
} c)OQ_3xOs
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privatestaticint getEveryPage(int everyPage){ 7 xm>+(
return everyPage == 0 ? 10 : everyPage; c:MP^PWc
} IH1
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e
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privatestaticint getCurrentPage(int currentPage){ U6@j=|q
return currentPage == 0 ? 1 : currentPage; #^fDKM
} `-L{J0xq
VCZ.{MD
privatestaticint getBeginIndex(int everyPage, int 0WI3m2i
RZV6\j
currentPage){ {\+!@?
return(currentPage - 1) * everyPage; R3SAt-IE
} kG>d^K
^ LTKX`p
privatestaticint getTotalPage(int everyPage, int \-B8`ah
J2W: Q
totalRecords){ R4Vi*H
int totalPage = 0; {m/h3hjFa
]N+(SU
if(totalRecords % everyPage == 0) WM_wkvYl
totalPage = totalRecords / everyPage; 'X$2gD3c9
else g~JN"ap
totalPage = totalRecords / everyPage + 1 ; %4~2
],HF)21
return totalPage; q'%-8t
} <k0$3&D
se1\<YHDS
privatestaticboolean hasPrePage(int currentPage){ z\fmwI
return currentPage == 1 ? false : true; -W5ml
@
}
k_ ;+z
nDvj*lZF
privatestaticboolean hasNextPage(int currentPage, X)^kJ`
-kVt_
int totalPage){ l|c#
return currentPage == totalPage || totalPage == M/X&zr
*uq;O*s
0 ? false : true; O%.c%)4Xo
} pLvvv#Y
`|\z#Et
;LM,<QJ
} s6|EvIVM
Rs0O4.yi;@
jF}u%T)HL
CnT]uU
t`6R)'
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 VuqJ&U.-
z+>FKAF
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 b3z{FP
9K\A4F}
做法如下: Qb}1tn)
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 G:HPd.ay
JlZU31Xws
的信息,和一个结果集List: %4/>7 aB]Y
java代码: _{fh/{b1
<lj;}@qQ<
f?OFMac
/*Created on 2005-6-13*/ Ungex@s_
package com.adt.bo; ([y 2x.kd
Ydw04WEJ
import java.util.List; _<`j?$P
t7"vAjZU
import org.flyware.util.page.Page; Uk=-A
@q
GS%ACk
/** fZQC'Z>EX
* @author Joa 38Q>x
*/ h
<s.o#8
publicclass Result { u dhj$:t
mT@8(
private Page page; xU4,R cgo
SL9]$M mJn
private List content; o\oS_f:RD
^{3,ok*Nf
/** 9U[
A
* The default constructor BM_hW8&G
*/ \zA G#{
public Result(){ |#p`mc%f~\
super(); qHT_,\l2
} Q:6i
3 Nr/
aXAV`%b
/** 'rZYl Qm
* The constructor using fields Cy'0O>v5
* 3]=j!_yJf
* @param page \^$g%a
* @param content Fc{X$hh<
*/ vN`2KCl~3
public Result(Page page, List content){ \G+ hi9T(
this.page = page; FwB}@)3
this.content = content; <6_RWtU
} .d)X.cO
RqV* O}Am
/** j:)"s_
* @return Returns the content. [YbnpI
*/ IUt/V^
publicList getContent(){ W$g<nhLK
return content; Vz(O=w=
} ZK1H%&P=R
zJhG`iWFw
/** \uT2)X( N
* @return Returns the page. a^U)2{A*f
*/ U}w,$
Y
public Page getPage(){ +K6j p
return page; k}xXja*
} e}
=tUdDf
{$,t^hd
/** lr>P/W\
* @param content f~HC%C
YH
* The content to set. @WmEcX|
*/ s4RqY*VK
public void setContent(List content){ ]kXiT Yg
this.content = content; k,p:!S(bl
} ws!pp\F
c7~+ 5
/** : MfY8P)
* @param page O] T'\6w
* The page to set. 4CUzp.S`h
*/ 4'Svio
publicvoid setPage(Page page){ &:K!$W
this.page = page; 2U;6sn*e
} <OQn|zU\
} S}@J4}*u["
kx6AMx!nX
!^~
^D<
n};:*N!
v
7Nu.2q E
2. 编写业务逻辑接口,并实现它(UserManager, TuF;>{~}
,".1![b
UserManagerImpl) qL;OE.?oA
java代码: P2U^%_~
`7v"(
>(>,*zP<9
/*Created on 2005-7-15*/ Q L0
package com.adt.service; {5%u G2g
DZ-2Z@{PX
import net.sf.hibernate.HibernateException; C;mcb$@
Pv- i.
import org.flyware.util.page.Page; | z1
I&m C
import com.adt.bo.Result; ~AqFLv/%
0j}!4D+
/** ^Z
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* @author Joa e}xx4mYo
*/ .paKV"LJ
publicinterface UserManager { V8Lp%*(3
$,@PY5r
public Result listUser(Page page)throws DW@|H
r |H 1Yy
HibernateException;
;rH<
xaPaK-
} LqZsH0C
`>i8$q%
@N
tiT,3k
%<^IAMkp
QPc4bg\J~t
java代码: ZOAHM1ci
&nKb<o
xtWwz}^8]
/*Created on 2005-7-15*/ WQJnWe
package com.adt.service.impl; ?M<q95pL
3PLYC}Jq
import java.util.List; PVC Fh$pnw
0*=[1tdWY
import net.sf.hibernate.HibernateException; yi29+T7j4S
UrMEL;@g
import org.flyware.util.page.Page; sz"N,-<Ig
import org.flyware.util.page.PageUtil; qKSS 2f $
O`M6=\
import com.adt.bo.Result; [3@Pu.-I+M
import com.adt.dao.UserDAO; eYpK!9
import com.adt.exception.ObjectNotFoundException; Z,jR:_p
import com.adt.service.UserManager; _A>?@3La9
k1.h |&JJN
/** K *QRi/O
* @author Joa %X5p\VS\7
*/ mqt$'_M
publicclass UserManagerImpl implements UserManager { ~; V5*t
L?Fb}
private UserDAO userDAO; H Q_IQ+
D&dh>Pe1;
/** ^t2b`n60
* @param userDAO The userDAO to set. 6E)emFkQ
*/ "mtEjK5
publicvoid setUserDAO(UserDAO userDAO){ rk E;OU
this.userDAO = userDAO; iAl.(j
} j;7:aM"BQW
*^+]`S
/* (non-Javadoc) j5Cf\*B4J
* @see com.adt.service.UserManager#listUser hFQ*50n}
(:9=M5d
(org.flyware.util.page.Page) k#oe:u`<
*/ 'PS_|zI
public Result listUser(Page page)throws j*6>{_[
: Yb_
HibernateException, ObjectNotFoundException { K!<3|d
int totalRecords = userDAO.getUserCount(); 83i;:cn
if(totalRecords == 0) >d9b"T
throw new ObjectNotFoundException )wM881_!
)w_hbU_Pb&
("userNotExist"); aA6m5
page = PageUtil.createPage(page, totalRecords); 75"&"*R/*G
List users = userDAO.getUserByPage(page); {0o,2]o!:
returnnew Result(page, users); YXlaE=9bn
} /a .XWfu
v;WfcpWq2
} {hH8+4c7
H"; !A=0
8
U<$u,WS
\dHdL\f
sJ>JHv
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =mp"=%
6N#0D2~^
询,接下来编写UserDAO的代码: uBUT84i
3. UserDAO 和 UserDAOImpl: U>-GM>
java代码: i"h~QEE
o'KBe%@/
1G}\IK1+
/*Created on 2005-7-15*/ cD5N'3
package com.adt.dao; ev[!:*6P
mb?r{WCi
import java.util.List; ) >H11o{&
X
2Zp@q(
import org.flyware.util.page.Page; p6&6^v\
']:>Ww.S
import net.sf.hibernate.HibernateException; bCg)PJuB
rUW/d3y
/** 0PdX>h.t
* @author Joa *v:o`{vM[
*/ -d]v6q'1
publicinterface UserDAO extends BaseDAO { 0 /)OAw"m
i4dy0jfN
publicList getUserByName(String name)throws [KW9J}]
NcyE_T
HibernateException; xFj<KvV[
\!Wph5wA
publicint getUserCount()throws HibernateException; jV.9d@EC
5?34<B
publicList getUserByPage(Page page)throws 5@nvcCp
\B
Uno6
HibernateException; !F08F>@D
l,k.Jo5
} aE2Yl
FwpTQix!
W5(.Hub}
m0,TH[HWGF
~(-df>
java代码: A2%RcKY7
p7p6~;P
G<FB:?|
/*Created on 2005-7-15*/ iTVepYv4m
package com.adt.dao.impl; v@1f,d
{wptOZ
import java.util.List; ;XI=Y"h{%
c{{RP6o/j=
import org.flyware.util.page.Page; [<JY[o=
C,) e7
import net.sf.hibernate.HibernateException; e8U6D+jY
import net.sf.hibernate.Query; zxrbEE Q
hr?0RPp}
import com.adt.dao.UserDAO; 'p&q}IO
5n1T7-QCL
/** r:Ok z
* @author Joa >l =;6QL
*/ *lBX/O`=
public class UserDAOImpl extends BaseDAOHibernateImpl l}XnCOIT,
Z!z#+G
implements UserDAO { V5!mV_EoR@
; 6q`c!p7
/* (non-Javadoc) ;0nL1R]w(
* @see com.adt.dao.UserDAO#getUserByName {q/D,Rh8
0[92&:c,
(java.lang.String) ,D93A
*/ +-PFISa<r
publicList getUserByName(String name)throws O6b.oS'-
q\d/-K
HibernateException { M!O &\2Q
String querySentence = "FROM user in class $p\ 0/
`C)|}qcC
com.adt.po.User WHERE user.name=:name"; Og :aflS
Query query = getSession().createQuery 3z!^UA>q
Gf<%bQE
(querySentence); y:VY8a 4
query.setParameter("name", name); e[g.&*!
return query.list(); dG%{&W9
} )dF`L
FJIo]p
/* (non-Javadoc) 0GcOI}
* @see com.adt.dao.UserDAO#getUserCount() ?1]h5Uh[b
*/ Wo,fHY
publicint getUserCount()throws HibernateException { .tzQ
hd>
int count = 0; gezZYP)d
String querySentence = "SELECT count(*) FROM i,mo0CSa
iz:O]kI
user in class com.adt.po.User"; "[2D&\$
Query query = getSession().createQuery znNv;-q
t}2M8ue(&
(querySentence); r~; TId} #
count = ((Integer)query.iterate().next DC,]FmWs!+
uE&2M>2
()).intValue(); Ta)6ly7'
return count; PHg(O:3WG
} o(Q='kK
`m\l#r2C
/* (non-Javadoc) N3|aNQ=X0
* @see com.adt.dao.UserDAO#getUserByPage AfJ .SNE
otJHcGv
(org.flyware.util.page.Page) 4@"n7/<
*/ ke5_lr(
publicList getUserByPage(Page page)throws f4+}k GJN
Yp6%
@c6\
HibernateException { 2-DJ3OL]k
String querySentence = "FROM user in class %s#`Z [8,
.!Q?TSQ+{!
com.adt.po.User"; 4/QQX;w
Query query = getSession().createQuery -3Auo0
y9-}LET3j
(querySentence); Wf9K+my
query.setFirstResult(page.getBeginIndex()) kg()C%#u
.setMaxResults(page.getEveryPage()); #W[C;f|,
return query.list(); 2D"\Ox
} DTM
xfQdk
J85Kgd1
\a
} W%P0X5YQ
Qh,Dcg2ZM"
z1~FE
F!&_
m^Rf6O^
至此,一个完整的分页程序完成。前台的只需要调用 k4BiH5\hA
Kv#TJn
userManager.listUser(page)即可得到一个Page对象和结果集对象 =d1R9O
XV0t
8#T2
的综合体,而传入的参数page对象则可以由前台传入,如果用 42 &m)
L`0}wR?+
webwork,甚至可以直接在配置文件中指定。 Z=y^9]
@+^5ze\
下面给出一个webwork调用示例: a+p_47 xa
java代码: :~B'6b
%|gj46
]?j[P=\
/*Created on 2005-6-17*/ =y1/V'2E
package com.adt.action.user; hxj[gE'R(
nY=]KU
import java.util.List; a3(q;^v
bcE%EQ
import org.apache.commons.logging.Log; \&1Di\eL
import org.apache.commons.logging.LogFactory; q@&.)sLPgO
import org.flyware.util.page.Page; UZ3oc[#D=]
.[hbiv#
import com.adt.bo.Result; e(;nhU3a*,
import com.adt.service.UserService; I
DtGtkF
import com.opensymphony.xwork.Action; Zmr*$,v<y
sp&)1?!M
/** uY*|bD`6&
* @author Joa 7Jvb6V<R
*/ PU{7s
publicclass ListUser implementsAction{ ]QK@zb}x
9lCZi?
privatestaticfinal Log logger = LogFactory.getLog ,L,?xvWG
zFGZ;?i
(ListUser.class); SBqx_4}
`DcZpd.n
private UserService userService; \`,,r_tO
'UL"yM
private Page page; @qWes@
S!wY6z
privateList users; *WX,bN6Ot
SPU_@ Pk
/* aBx8wl*Vm
* (non-Javadoc) K#oF=4_/|
* $ h<l
* @see com.opensymphony.xwork.Action#execute() x1nqhSaD
*/ c=A)_ZFg
publicString execute()throwsException{ LG3:V'|
Result result = userService.listUser(page); %$.]g
page = result.getPage(); {Tym#
users = result.getContent(); }Qo:;&"3
return SUCCESS; 97n@HL1
} < &~KYu\r
_'47yq^O
/** En]+mIEo
* @return Returns the page. pX/,s#dY>
*/ X1{U''$
K
public Page getPage(){ }^Kye23
return page; C!r9+z)<
} nkvkHh
_&
qM^
/** rxJWU JMxK
* @return Returns the users. N#? Ohz
*/ $Q!J.}P@
publicList getUsers(){ p4-bD_
return users; _laLTP*
} =2yg:D
_N-JRM m<
/** ~Q)137u]P
* @param page a;$'A[hq
* The page to set. .^J7^Ky,
*/ MVpk/S%W
publicvoid setPage(Page page){ b#<@&0KE
this.page = page; zxt&oT0Q
} |2eF~tJqc
<M4Qc12jP
/** KoPhPH
* @param users (}C%g{8
* The users to set. .`ppp!:a4
*/
0^PI&7A?y
publicvoid setUsers(List users){ ^%qhE8
this.users = users; .g6DKjy>
} p&%M=SzN
x>yeF,q1
/** 8 O5@FU
3
* @param userService 'F665
* The userService to set. + ^9;<>P
*/ i+z;tF`
publicvoid setUserService(UserService userService){ wEImpsC`
this.userService = userService; CdN,R"V0$@
} @Yy:MdREA
} yb(zyGe
D>c-h)2|
oqOXRUy
-gP4| r8&
!hJ%
:^ xL
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, mfNYN4Um6
*?#t (Y[
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 ,^_aqH
p|D-ez8
么只需要: 6jIW)C
java代码: = yH#Iil
*qLOr6
){.J`X5r
<?xml version="1.0"?>
IiV#V
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork (HUGgX"=
;-koMD!2F
1.0//EN" "http://www.opensymphony.com/xwork/xwork- mj{/'
G1d!a6>
1.0.dtd"> qOKC2WD
EQ j2:9f
<xwork> f
V|Zh
vh~:{akR
<package name="user" extends="webwork- jaj."v
Q7]VB p4
interceptors"> }Dig'vpMx
btC.EmX
<!-- The default interceptor stack name ;b""N,
myj^c>1Iz
--> U 6y
;V
<default-interceptor-ref U-$ B"w &
N2"4dVV;
name="myDefaultWebStack"/> []{g9CO
bD[6)
ITg
<action name="listUser" h%Nbx:vKk
7b2N'^z}
class="com.adt.action.user.ListUser"> %0PZZl5b
<param @' Er&[P
C<.t'|
name="page.everyPage">10</param> 7b_Ihv
<result qR~s&SC#
BW>f@;egg
name="success">/user/user_list.jsp</result>
4^L+LY
</action> (BgO<
%EuXL% B
</package> od- 0wJN-m
aQ ~
</xwork> 'y#kRC=G:
/#PEEN
)p MZ5|+X
VK+#!!Ha
z^/aJ@gQ
P^%.7C
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 -4p^wNR
1u\fLAXn
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。 |4i,Vkfhe
$V"~\h8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 _ "ysJ&
`'u|4pRFs
:B=p%C
'\:?FQ
C
XV2f|8d>
我写的一个用于分页的类,用了泛型了,hoho IkSzjXE{
t/,k{5lX
java代码: Cm;WQuv@
#;
I8 aMb
rs@,<DV)u
package com.intokr.util; =;{vfjj
?o h3t
import java.util.List; m7 !Fb
^P-!pK*
/** Ed|7E_v
* 用于分页的类<br> 'M\ou}P
* 可以用于传递查询的结果也可以用于传送查询的参数<br> xA nAW
* Llf>C,)
* @version 0.01 G!uQ|<(
* @author cheng G }<q
*/ %Gn(b1X
public class Paginator<E> { A+j~oR
privateint count = 0; // 总记录数 AZ5c^c)
privateint p = 1; // 页编号 #Dx$KPD
privateint num = 20; // 每页的记录数 bwo" s[w
privateList<E> results = null; // 结果 a%f5dj+
m=2TzLVv
/** /^v4[]
* 结果总数 }k}5\%#li5
*/ l[^bo/
publicint getCount(){ Mg95us
return count; Q]7Q4U
} _OT kv6;4n
EkV v
publicvoid setCount(int count){ nX>k}&^L
this.count = count; /Mf45U<
} LiJ;A*
U %Aj~K^b
/** il-v>GJU7{
* 本结果所在的页码,从1开始 T7n;Bf
* 9VIsLk54^
* @return Returns the pageNo. ;W#G<M&n'
*/ *#EyfMz-B
publicint getP(){ Tk/K7h^
return p; m%q#x8Fp
} 3Nw9o6` U
E/_=0t
/** -4b9(
* if(p<=0) p=1 Yc#o GCt
* XaD}J:X q
* @param p kaUH#;c>_
*/ D6_16PJE
publicvoid setP(int p){ 33couAP#
if(p <= 0) }?>30+42:
p = 1; }(J6zo9(x
this.p = p; 1S\q\kz->D
} yA(H=L-=!1
&nj@t>5Bs$
/** hW>@jT"t1C
* 每页记录数量 Kd;|Z
*/ qX:54$t
publicint getNum(){ O" ['.b
return num; +S|y)W8
} E](Ood
w0moC9#$?
/** 1h]Dc(Oc#=
* if(num<1) num=1 "xS",6Sy
*/ wamqeb{u
publicvoid setNum(int num){ LtH;#Q
if(num < 1) Yk<?HNf
num = 1; &e_M \D
this.num = num; (q*T.
} V|xR`Q
0_qqBL.4
/** *BBP"_$
* 获得总页数 a+zE`uY
*/ K*;=^PY
publicint getPageNum(){ X"8Jk4y
return(count - 1) / num + 1; |)pT"`
} H*yX
Iq:
PWL Mux
/** VILzx+v
M
* 获得本页的开始编号,为 (p-1)*num+1 (sO;etW
*/ R$(,~~MH
publicint getStart(){ <+sv7"a
return(p - 1) * num + 1; #(bMZ!/(
} `6lc] r
Hc^b}A y7
/** lh~!cOm\=E
* @return Returns the results. 7u\^$25+h
*/ ZxbWgM5rm
publicList<E> getResults(){ ,+,""t
return results; 49_b)K.tB
} ] 2FS=
6!Ji-'\"
public void setResults(List<E> results){ ;2)@NH
this.results = results; t1g)Y|@d
} 69r<Z
Gnj|y?'
public String toString(){ WK/Byd.Z
StringBuilder buff = new StringBuilder (Pc:A!}
*"O7ml]
(); ./[%%"
buff.append("{"); cRT@Cu
buff.append("count:").append(count); 2@:Go`mg
buff.append(",p:").append(p); 5"^$3&)
buff.append(",nump:").append(num); 6/.-V1*O
buff.append(",results:").append ?$pp%
U $X"W'
(results); id&;
buff.append("}"); ?J6J#{LRd
return buff.toString(); Z!~~6Sq
} CdatN$/*
ga6M8eOI
} ~e ]83?
m}Kn!21
5RI"gf