Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 )#b}qc#`
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 }$&T
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 ++J Bbuzj!
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 dK0}% ]i3#
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分页支持类: _H^^2#wc/
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java代码: K]H"qG.K
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package com.javaeye.common.util; i#@ v_^ q
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import java.util.List; KV^:sxU
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publicclass PaginationSupport { ~WYE"(
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publicfinalstaticint PAGESIZE = 30; PK.h E{R
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privateint pageSize = PAGESIZE; xoz*UA.
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privateList items; 323yAF
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privateint totalCount; GDo)6du
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privateint[] indexes = newint[0]; &dZ.+#8r
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privateint startIndex = 0;
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public PaginationSupport(List items, int K*HVn2OV
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totalCount){ xvdnEaWe$
setPageSize(PAGESIZE); ;:-2~z~~
setTotalCount(totalCount); A3
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setItems(items); %4r!7X|O<
setStartIndex(0); .=b
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} .^9/ 0.g8t
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public PaginationSupport(List items, int )'K!)?&d
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totalCount, int startIndex){ vZ_DG}n11
setPageSize(PAGESIZE); W)$|Hm:H
setTotalCount(totalCount); 5x1%oC
setItems(items); 5Re`D|8
setStartIndex(startIndex); R
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} %Zl_{Q]h
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public PaginationSupport(List items, int X."h Tha5
dp// p)B>
totalCount, int pageSize, int startIndex){ psyH?&T
setPageSize(pageSize); 0+2Matk>.
setTotalCount(totalCount); "u,~yxYWl
setItems(items); -+
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setStartIndex(startIndex); p@N Er,GB
} My6]k?;}(
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publicList getItems(){ vUIK4uR.
return items; x
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}
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publicvoid setItems(List items){ .2(@jx,[
this.items = items; y?R <g^A
} PU@U@
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publicint getPageSize(){ 6q
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return pageSize; k+m_L{#m5
} g6a3MJV`
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publicvoid setPageSize(int pageSize){ c;t(j'k`
this.pageSize = pageSize; (?&_6B.*
} ! 4^L $
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publicint getTotalCount(){ C)3$";$5)
return totalCount; h}B# 'e
} 6 peM4X
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publicvoid setTotalCount(int totalCount){ }Bod#|`
if(totalCount > 0){ 7N~qg 7&
this.totalCount = totalCount; 7q{v9xKy
int count = totalCount / @SQ*/sw (c
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pageSize; W*/s4 N
if(totalCount % pageSize > 0) n`I
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count++; 5@&i:vs5y
indexes = newint[count]; @Ozf}}#
for(int i = 0; i < count; i++){ yV]-Oa$*s0
indexes = pageSize * zC>(!fJqq
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} EV7+u0uN&Q
}else{ ,IVr4#w0=
this.totalCount = 0; +KwF
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} e[k;SSs
} >0;"qT
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publicint[] getIndexes(){ HI?~t|[y
return indexes; JpHsQ8<
} j
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publicvoid setIndexes(int[] indexes){ C2,cyhr
this.indexes = indexes; Mp@(/
} ;0X|*w1JO
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publicint getStartIndex(){ N n-6/]d#
return startIndex; Ex s _LN
} +MoxvW6
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publicvoid setStartIndex(int startIndex){ O>):^$-K%
if(totalCount <= 0) #pn AK
this.startIndex = 0; 90if:mYA
elseif(startIndex >= totalCount) K'rs9v"K|
this.startIndex = indexes Nm:<rI,^
N, +g/o\f
[indexes.length - 1]; #1!BD!u
elseif(startIndex < 0) |`D5XRVbi
this.startIndex = 0; Q@.9wEAJ
else{ _.8]7f`*Gc
this.startIndex = indexes ^l2d?v8
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[startIndex / pageSize]; X'Il:SK
} !J?=nSu
} OsSiBb,W79
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publicint getNextIndex(){ AkQFb2|ir
int nextIndex = getStartIndex() + ?}Ptb&Vk(
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pageSize; VKfHN_m*
if(nextIndex >= totalCount) /ykxVCvAt
return getStartIndex(); {kO:HhUg
else J2k'Ke97o
return nextIndex; NeZYchR
} tZBE& :l
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publicint getPreviousIndex(){ =xWW+w!r
int previousIndex = getStartIndex() - nk,Mo5iqV
MJR\ g3
pageSize; ;}9Ws6#XQs
if(previousIndex < 0) 9@>hm>g.
return0; 0$h$7'a
else K>JU/(
return previousIndex; -ddatc|
} qvE[_1QCc
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} ;Wm)e~`,
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抽象业务类 >h-6B=
java代码: ?Lb7~XKt\
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/** #Z5Wk
* Created on 2005-7-12 3>3ZfFC
*/ KEB>}_[
package com.javaeye.common.business; /FZ )ej\
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import java.io.Serializable; 7uH{UpslJ
import java.util.List; nE$ V<Co}
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import org.hibernate.Criteria; 05zdy-Fb
import org.hibernate.HibernateException; |}Z"|-Z
import org.hibernate.Session; `.Q3s?1F
import org.hibernate.criterion.DetachedCriteria; 0# GwhB
import org.hibernate.criterion.Projections; v"TH[}C9D
import ?^GsR[-x
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org.springframework.orm.hibernate3.HibernateCallback; 5.UgJ/
import J, U~.c
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org.springframework.orm.hibernate3.support.HibernateDaoS F<<H [,%0
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upport; WoR**J?}w
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import com.javaeye.common.util.PaginationSupport; v333z<<S
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public abstract class AbstractManager extends _
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HibernateDaoSupport { +/8?+1E ^
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privateboolean cacheQueries = false; P?ol]MwaB
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privateString queryCacheRegion; @TG~fJSA12
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publicvoid setCacheQueries(boolean o: DnZN
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cacheQueries){ 3{E}^ve
this.cacheQueries = cacheQueries; Mi-9sW
} +& Qqu`)?F
}('QIvq2
publicvoid setQueryCacheRegion(String 6%axbB
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queryCacheRegion){ g
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this.queryCacheRegion = v65r@)\`
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queryCacheRegion; b=go"sJ@>(
} Um&@
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publicvoid save(finalObject entity){ (acRYv(
getHibernateTemplate().save(entity); _~<TAFBr
} uf3 gVS_h=
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publicvoid persist(finalObject entity){ {(Z1JoSl
getHibernateTemplate().save(entity); EFO Q;q
} @35]IxD
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publicvoid update(finalObject entity){ 9LRY
getHibernateTemplate().update(entity);
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} k{8N@&D
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publicvoid delete(finalObject entity){ l)bUHh5[
getHibernateTemplate().delete(entity); 0$
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} w|#79,&
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publicObject load(finalClass entity, ThB2U(Wf
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finalSerializable id){ 81g0oVv
return getHibernateTemplate().load s#sXr
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(entity, id); OMNdvrE*=O
} JJO"\^,;~
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publicObject get(finalClass entity, N9Vcp~;
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finalSerializable id){ Su~`jRN$
return getHibernateTemplate().get ,;}RIcvQV
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(entity, id); nwYeOa/t
} ,kI1"@Tu
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publicList findAll(finalClass entity){ xCD+qP^
return getHibernateTemplate().find("from kE}Ib4]J
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" + entity.getName()); /xnhHwJm
} 7Q&P4{hi0
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publicList findByNamedQuery(finalString g;1
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namedQuery){ 6w#v,RDEu
return getHibernateTemplate e V#H"fM
c{0?gt.
().findByNamedQuery(namedQuery); Q=E6ZxH5;
} ]a()siT
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publicList findByNamedQuery(finalString query, LgYzGlJp
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finalObject parameter){ 3m'6 cMQ
return getHibernateTemplate BDg /pDnwg
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().findByNamedQuery(query, parameter);
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} 'Z[R*Ikzq
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publicList findByNamedQuery(finalString query, *BV .zbGm
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finalObject[] parameters){ S3r\)5%;
return getHibernateTemplate >'eqOZM
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().findByNamedQuery(query, parameters); VrG |/2
} !.A>)+AK
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publicList find(finalString query){ nK[$ID
return getHibernateTemplate().find - =Hr|AhE
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(query); !~#31kL&
} ( KrIMZ
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publicList find(finalString query, finalObject <f%9w]
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parameter){ :d;5Q\C`
return getHibernateTemplate().find }% =P(%-
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(query, parameter); gVc[`(@h
} "#()4.9
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public PaginationSupport findPageByCriteria =W6P>r_
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(final DetachedCriteria detachedCriteria){ {XAKf_Cg
return findPageByCriteria "v06Fj>q
x+&&[>-P
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Jg:'gF]jt
} q&.!*rPD
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public PaginationSupport findPageByCriteria />?d
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(final DetachedCriteria detachedCriteria, finalint >3JOQ;:d8
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startIndex){ 9f
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return findPageByCriteria CfAqMH*ip
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(detachedCriteria, PaginationSupport.PAGESIZE, tP UQ"S
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startIndex); l/]P6 @N
} Kfi A 7W
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public PaginationSupport findPageByCriteria R#t~i&v/
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(final DetachedCriteria detachedCriteria, finalint /[IK[
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pageSize, 3ySnA AG
finalint startIndex){ 3+Q6<MS
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return(PaginationSupport) &45.*l|mo
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getHibernateTemplate().execute(new HibernateCallback(){ gyPF!"!5dq
publicObject doInHibernate h(Z7a%_
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(Session session)throws HibernateException { Og["X0j
Criteria criteria = uGv+c.~[j
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detachedCriteria.getExecutableCriteria(session); %l,Xt"nS#
int totalCount = a8N!jQc_m
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((Integer) criteria.setProjection(Projections.rowCount b`2~
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()).uniqueResult()).intValue(); 2`z+_DA
criteria.setProjection +5Mx0s(5
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(null); Y3thW@mD05
List items = }>j$Wr_h
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criteria.setFirstResult(startIndex).setMaxResults @=9QV3D
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(pageSize).list(); XdB8Oj~~
PaginationSupport ps = sU`#d
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new PaginationSupport(items, totalCount, pageSize, h_cZ&P|
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startIndex); xGA%/dy,;
return ps; 1.uyu
} +n0y/0Au
}, true); SZgH0W("L
} |h3YL!
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public List findAllByCriteria(final /5o~$S
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DetachedCriteria detachedCriteria){ @M(vaJB8u
return(List) getHibernateTemplate ,
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().execute(new HibernateCallback(){ eVy,7go h
publicObject doInHibernate 9;@6iv
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(Session session)throws HibernateException { old}}>_
Criteria criteria = +pE-Yn`YS
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detachedCriteria.getExecutableCriteria(session); j3FDGDrg
return criteria.list(); Tx!mW-Lt
} E)`+1j
}, true); lwK Au!l
} 6VA@ ;g0$
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public int getCountByCriteria(final `=FfzL
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DetachedCriteria detachedCriteria){ +VTMa9d
Integer count = (Integer) J3K!@m_\
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getHibernateTemplate().execute(new HibernateCallback(){ TEY%OIzU+
publicObject doInHibernate /N~.,vf
c(@)V.o2
(Session session)throws HibernateException { E$RH+):|
Criteria criteria = +4)Kc9S#
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detachedCriteria.getExecutableCriteria(session); h'wI/Z_'
return l2$6ojpo
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criteria.setProjection(Projections.rowCount Ix}:!L
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()).uniqueResult(); HogT#BMs
} 1}'|HAu
}, true); +}%4]O;
return count.intValue(); MbF.KmV
} <zrGPwk
} UE*M\r<
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用户在web层构造查询条件detachedCriteria,和可选的 58WL8xu
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 @<;0h|
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PaginationSupport的实例ps。 {8'I+-
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ps.getItems()得到已分页好的结果集 .]P@{T||Y
ps.getIndexes()得到分页索引的数组 9z,V]v=
ps.getTotalCount()得到总结果数 rtC.!].;%
ps.getStartIndex()当前分页索引 iE>T5XV8$B
ps.getNextIndex()下一页索引 TTu<~GH
ps.getPreviousIndex()上一页索引 !@5B:n*
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $SA8$!:
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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 d%8hWlffz
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一下代码重构了。 )BmK'H+l
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我把原本我的做法也提供出来供大家讨论吧: |]*]k`o<)
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首先,为了实现分页查询,我封装了一个Page类: DavpjwSn
java代码: :[A>O(
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/*Created on 2005-4-14*/ ncjtv"2R
package org.flyware.util.page; z^'3f!:3
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/** V]&0"HX2r!
* @author Joa <XDYnWz
* &3#19v7/
*/ ===M/}r
publicclass Page { \c (R#*0,
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/** imply if the page has previous page */ {d|e@`"T
privateboolean hasPrePage; 2guWWFS
%L, mj
/** imply if the page has next page */ L/t'|<m
privateboolean hasNextPage; iK%%
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/** the number of every page */ jv_z%`
privateint everyPage; sT
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/** the total page number */ 2 ,RO
privateint totalPage; 'So,*>]63
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/** the number of current page */ C+tB$yahO
privateint currentPage; 2SVBuV/R
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/** the begin index of the records by the current ^/b3_aM5d
'~{bq'7`m
query */ Okxuhzn>"
privateint beginIndex; F5s Pd
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j%%& G$Tfu
/** The default constructor */ I5Vp%mCY
public Page(){ T8'm{[C
&![3{G"+>l
} ^V,?n@c!
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/** construct the page by everyPage oU"!"t
* @param everyPage u2\QhP 9
* */ Fp=O:]
public Page(int everyPage){ !79eF)
this.everyPage = everyPage; -9)H[}.
} b%A+k"d
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/** The whole constructor */ (t[sSl
public Page(boolean hasPrePage, boolean hasNextPage, csK;GSp}
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int everyPage, int totalPage, v_G1YC7TU
int currentPage, int beginIndex){ !DU4iq_.
this.hasPrePage = hasPrePage; 7F$G.LhMw
this.hasNextPage = hasNextPage; J> Z.2
this.everyPage = everyPage; UmEc")3
this.totalPage = totalPage; \k
9EimT}
this.currentPage = currentPage; sH_B*cr3
this.beginIndex = beginIndex; "($"T v2
} j; TXZ`|(
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/** Te d1Ky2O
* @return +%sMd]$,n
* Returns the beginIndex. Lqa|9|!
*/ KATu7)e&~^
publicint getBeginIndex(){ |&u4Q /0
return beginIndex; y
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} qe[P'\]L
H3#rFO"C*
/** W6^YFN
* @param beginIndex o$q})!
* The beginIndex to set. Gg TrIF
*/ 7ILb&JQ!%{
publicvoid setBeginIndex(int beginIndex){ [Fk|%;B/~
this.beginIndex = beginIndex; 2]:Z7Ji
} .(g"(fgF
]L6[vJHx
/** &RB{0Qhx
* @return }kZ)|/]kn
* Returns the currentPage. Q'~3Ik
*/ -^ceTzW+
publicint getCurrentPage(){ +?9.
&<?
return currentPage; 7MZ(tOR
} 328gTP1
CpLLsp hy
/** ;Z 6ngS
* @param currentPage B>r>z5
* The currentPage to set. sD=iHO
Am
*/ T|^KG<uPV!
publicvoid setCurrentPage(int currentPage){ 6^vz+oN
this.currentPage = currentPage; HRg< f= oz
} >xCc#]v&
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/** +yd{-iH
* @return B%(-UTQf
* Returns the everyPage. 9f #6Q*/
*/ hMnJH_siY
publicint getEveryPage(){ ~5:-;ZbZ
return everyPage; ]@A31P4t|
} H^fErl
v43FU3
/** 2fFGS.l
* @param everyPage x5(B(V@b
* The everyPage to set. \Xpq=2`
*/ v5A8"&Jr
publicvoid setEveryPage(int everyPage){ ?#gYu%7DN
this.everyPage = everyPage; !SAR/sdXf
} A(1dq
v=J[p;H^H
/** dOFK;
* @return M/evZ?uis
* Returns the hasNextPage. "JpnmE[`
*/ 9jf2b
publicboolean getHasNextPage(){ <sor;;T
return hasNextPage; snvixbN
} |PutTcjQ
><w=
/** cz;gz4d8
* @param hasNextPage I?X!v6
* The hasNextPage to set. aX}:O
*/ T{4Ru6[
publicvoid setHasNextPage(boolean hasNextPage){ ay>u``$R
this.hasNextPage = hasNextPage; <2ymfL-q
} "yf#sEabV
!b{7gUjyI
/** &BE'~G
* @return IRK(y*6
* Returns the hasPrePage. }0
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*/ ;oivG)hJl
publicboolean getHasPrePage(){ V1 O]L66
return hasPrePage; U}:e-
} |m>{< :
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/** o l8|
* @param hasPrePage Rdl^-\BV
* The hasPrePage to set. rssn'h
*/ us >$f20T
publicvoid setHasPrePage(boolean hasPrePage){ gaVQ3NqF
this.hasPrePage = hasPrePage; cUD}SOW
} hx:"'m5
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/** VjGtEIew
* @return Returns the totalPage. -iySU 6
* $zD}hO9
*/ R6E.C!EI
publicint getTotalPage(){ *Ry{}|_8
return totalPage; j7v?NY
} ZE4xF8
$94l('B6H
/** ZuVes?&j
* @param totalPage L%5g]=
* The totalPage to set. }1?
2
*/ `>N_A!pr`
publicvoid setTotalPage(int totalPage){ .!yw@kg
this.totalPage = totalPage; 7!jbID~
} BjAmM*k
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} K pSho<
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HV\l86}
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 u
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个PageUtil,负责对Page对象进行构造: (@ixV$Y
java代码: N3?@CM^hHw
'/~j!H4q9
B,avI&7M;S
/*Created on 2005-4-14*/ vj4n=F,Z
package org.flyware.util.page; WN9K*Tt~o&
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import org.apache.commons.logging.Log; | x/Z
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import org.apache.commons.logging.LogFactory; ?nV& :~eY
_H)>U[
/** 4@1C$|k
* @author Joa QTbv3#
* 9vw0box
*/ q<>aZ|r
publicclass PageUtil { WJF#+)P:Y
k+`e0Jago
privatestaticfinal Log logger = LogFactory.getLog yp\sJc`
e sDd>W
(PageUtil.class); Y=tx
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/** *\T
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* Use the origin page to create a new page = 6^phZ(
* @param page mQqv{1
* @param totalRecords $G.ws
* @return iU9> qJ]
*/ 3lT>C'qq
publicstatic Page createPage(Page page, int XXA1%Lw%
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&s
totalRecords){ 9Bw.Ih[Z
return createPage(page.getEveryPage(), xji2#S%
#0gwN2Nv"L
page.getCurrentPage(), totalRecords); kSq1Q#Bxq
} 5fDnr&DR
J-)9>~[E<
/** /4lm=ZE/
* the basic page utils not including exception aEw wK(ny
k CVA~%d7
handler yx&'W_Q@
* @param everyPage jk-e/C
* @param currentPage CF_pIfbaf
* @param totalRecords 4;.y>~z
* @return page iQJ[?l`
*/ 0tyS=X;#e
publicstatic Page createPage(int everyPage, int OD`?BM
v\3}5v%YI
currentPage, int totalRecords){ 3r]N\c
everyPage = getEveryPage(everyPage); -
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currentPage = getCurrentPage(currentPage); @ZTsl ?
int beginIndex = getBeginIndex(everyPage, 72;ot`
rXG?'jN
currentPage); R0_O/o+{
int totalPage = getTotalPage(everyPage, QGpAG#M9?
568qdD`PS
totalRecords); 2c4x=%
boolean hasNextPage = hasNextPage(currentPage, mZ^ev;
WZ]f \S
totalPage); C=uYX"
boolean hasPrePage = hasPrePage(currentPage); [K4wd%+
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returnnew Page(hasPrePage, hasNextPage, NsY D~n
everyPage, totalPage, F,'rW:{HMt
currentPage, E3==gYCe*
\C eP.,<
beginIndex); ]31UA>/TI
} TE!+G\@
L}x,>hbT
privatestaticint getEveryPage(int everyPage){ X
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return everyPage == 0 ? 10 : everyPage; _0: }"!Gq
} S#wy+*
kvo V?<!
privatestaticint getCurrentPage(int currentPage){ N+M^e`H
return currentPage == 0 ? 1 : currentPage; MzudCMF
} %=GF
*sbZ{{]e
privatestaticint getBeginIndex(int everyPage, int ;%_s4
F:B8J4/
currentPage){ P/hV{@x
return(currentPage - 1) * everyPage; -=)Al^V4T
} @;K-@*k3
h.ln%6:d
privatestaticint getTotalPage(int everyPage, int U81--'@y
4Cn%
h)w
totalRecords){ MR{JMo=r
int totalPage = 0; O<EFm}Ae
$VRVMY [q
if(totalRecords % everyPage == 0) WXzSf.8p|
totalPage = totalRecords / everyPage; dW`!/OaQD
else GL<u#[
totalPage = totalRecords / everyPage + 1 ; -fILXu
iF#|Z$g-(
return totalPage; 2V6kCy@V
} eK)R=M@i
mIy|]e`SJ
privatestaticboolean hasPrePage(int currentPage){ 8\H*Z2yF+
return currentPage == 1 ? false : true; X@j.$0eK
} ]dj
W^C]94
2@~hELkk/E
privatestaticboolean hasNextPage(int currentPage, ~aZy52H_#.
h]{V/
int totalPage){ ?n0Z4 8%
return currentPage == totalPage || totalPage == D{) K00mm
yur5"$n
0 ? false : true; V@C8HTg
} "xK#%eJjWd
6";ew:Ih^
q<Sb>M/\,
} xxS>O%
uZ/XI {/
G9
g
-EP\
h%*@82DKK
(Q4hm ]<
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。 XGCjB{IV
}8e_
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 q@(MD3OE
mN&B|KWU
做法如下: SE7mn6,%\
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 \a7caT{
B}U:c]
的信息,和一个结果集List: +$;*" o
java代码: 2.>aL
M8{J
`:>N.9'o
/*Created on 2005-6-13*/ yRyUOTK
package com.adt.bo; ]I<w;.z
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import java.util.List; 92 oUQ EK
mNk@WY_F
import org.flyware.util.page.Page; 3[Xc:;+/
7]`l"=/z
/** Qt+i0xd
* @author Joa KKcajN
*/ 9
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publicclass Result { #M5pQ&yZy
kIwq%c;
private Page page; &ra2(S45
F>lM[Lu#
private List content; :6[G;F7s
vi;yT.
/** vKFEA7
* The default constructor 3n3$? oV
*/ F(DM$5z[
public Result(){ mTU[khEmL=
super(); )zv"<>Q 6
} \TS.9 >\
/)*si
/** !~_6S*~
* The constructor using fields HrS-o=
* ym;I(TC+
* @param page l0K_29^
* @param content #\l#f8(l
*/ *ORa@x
public Result(Page page, List content){ C1w6[f1+
this.page = page; ,~G:>q$ad
this.content = content; Q>g-xe 1
} <0btwsv}
dthtWnB@
/** 's\rQ-TV
* @return Returns the content. %%+@s
*/ h )% e
publicList getContent(){ P/,ezVb=
return content; Y;1s=B9
} u-u:7VtH0=
U7xKu75G1
/** |<2<`3
* @return Returns the page. J;S Z"I'
*/ t3<HE_B|
public Page getPage(){ kk$D:UQX
return page; )u=46EU_
} U&o~U] rm
hH]oJ}H \
/** t; b1<TLn0
* @param content 5;CqGzgoP
* The content to set. Z\S'HNU
*/ #Fckev4
public void setContent(List content){ B,4
3b O
this.content = content; ,E&W{b
} PnJA'@x
!N74y%=M
/** #SR )tU
* @param page FvyC$vip
* The page to set. J?/NJ-F
*/
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publicvoid setPage(Page page){ 7b*9
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this.page = page; G7k.YtW
} gJg%3K~,
} ow7*HN*
+a|u,'u
SN5Z@kK
BYZllwxwTE
l'RuzBQr
2. 编写业务逻辑接口,并实现它(UserManager, Q(BM0n)f
$%zM Z
UserManagerImpl) BWLeitS/
java代码: 7!A3PDAe
6)1xjE#
.#_g.0<
/*Created on 2005-7-15*/ oR}'I
package com.adt.service; v03^
;5:3 =F>ao
import net.sf.hibernate.HibernateException; ksV^Y=]
t]6
4=
import org.flyware.util.page.Page; ) %bY2
pk
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import com.adt.bo.Result; l-q.VY2
/jN&VpDG
/** fvM|Jb
* @author Joa TB#oauJm,
*/ g.x]x#BC
publicinterface UserManager { WZf}1.Mh*
`_E@cZ4
public Result listUser(Page page)throws
fYzZW
,,~|o3cfq
HibernateException; y2@8?
LLJsBHi-
} Os)}kkja
to3D#9Ep
c59l/qoz
$jN,]N~
F17nWvF
java代码: =Cp}iM
;op8r u
gro@+^DmT
/*Created on 2005-7-15*/ +$D~?sk
package com.adt.service.impl; f/]g@/`
+"D*0gYD
import java.util.List; sRSy++FRF
T0lbMp
import net.sf.hibernate.HibernateException; Z$ 6yB
H:`[$
^
import org.flyware.util.page.Page; h7[PU^ m
import org.flyware.util.page.PageUtil; nX-%qc"
&+7G|4!y
import com.adt.bo.Result; J@Qw6J
import com.adt.dao.UserDAO; psAdYEGk!
import com.adt.exception.ObjectNotFoundException; :a
y-2
import com.adt.service.UserManager; ^?gs<-)B
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/** =@go;,"
* @author Joa &g5+ |g (
*/ p Yaq1_<+
publicclass UserManagerImpl implements UserManager { 'E~[I"0
hFr?84sAd
private UserDAO userDAO; TkV*^j5
e"6!0Py#*
/** \&5t@sC
* @param userDAO The userDAO to set. CDgu`jj%]
*/ % yP*Vp,W
publicvoid setUserDAO(UserDAO userDAO){ ^FN(wvqb8
this.userDAO = userDAO; ypsT:uLT
} #ZPy&GIr
or..e
/* (non-Javadoc) \k)(:[^FY
* @see com.adt.service.UserManager#listUser Pdw[#X<[`
9Sk?tl
(org.flyware.util.page.Page) -<.b3M h
*/ pTk1iGfB
public Result listUser(Page page)throws :{KoZd
{;XO '
HibernateException, ObjectNotFoundException { Oj^qh+r
int totalRecords = userDAO.getUserCount(); J,]U"+;H
if(totalRecords == 0) y}!}*Qj+/
throw new ObjectNotFoundException BjIKs~CT
KsBi<wY
("userNotExist"); RE}$(T=
page = PageUtil.createPage(page, totalRecords); i& ybvTl
List users = userDAO.getUserByPage(page); =)9@rV&~
returnnew Result(page, users); 1b-_![&]1
} h?ZxS
x"QZ}28(t
} FZ^j|2.L*
yZ]u{LJS
JJ$q *
9Lv"|S`5W_
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其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ]:vo"{*C
01" b9`jU
询,接下来编写UserDAO的代码: 6!^&]4
3. UserDAO 和 UserDAOImpl: ]7yr.4?a
java代码: hIv8A_>@`
aZ{]t:]
Kt3]r:&J
/*Created on 2005-7-15*/ 8RJ^e[?o(
package com.adt.dao; 2[qlEtvQ
;VAHgIpx;
import java.util.List; R:t>PFwo
:7-2^7z)
import org.flyware.util.page.Page; rW(<[2 vg
j6_tFJT
import net.sf.hibernate.HibernateException; cq,0?2R`t
c$skLz
/** w`$M}oX(
* @author Joa A%$ZB9#zQ
*/ fyE#8h_>4
publicinterface UserDAO extends BaseDAO { s35`{PR
aX$Q}mgb
publicList getUserByName(String name)throws 3EN(Pz L
K7CrRT3>6
HibernateException; IDIok~B=e
M'D l_dx-
publicint getUserCount()throws HibernateException; "bC1dl<
k6?;D_dm
publicList getUserByPage(Page page)throws [R~`6
nPU=n[t8O
HibernateException; J*} warf&
]F4.m
} L d;))e
qXw^y
Z.DO 2=+=
TppuEC>
Lm{qFu
java代码: $)O=3dNbo
q&RezHK l
C6T?D5
/*Created on 2005-7-15*/ dRD t.U!T
package com.adt.dao.impl; b&j}f
RU_wr<
import java.util.List; 9_
+xc1cki_{
import org.flyware.util.page.Page; 9$[PAjwk
NM{/rvM
import net.sf.hibernate.HibernateException; mhDC1lXF
import net.sf.hibernate.Query; ;"K;D@xzh]
Jb (CH4|7
import com.adt.dao.UserDAO; 0mMoDJRy
,&5\`
/** cfP9b8JG
* @author Joa ~>"m`Q&[
*/ 1R+/T
public class UserDAOImpl extends BaseDAOHibernateImpl Ap<kK0#h
j
LS<S_`
implements UserDAO { IGQcQ/M
,|RN?1 ?U
/* (non-Javadoc) L
HW\A8
* @see com.adt.dao.UserDAO#getUserByName !w;oVPNg
;[-TsX:
(java.lang.String) n LD1j
*/ js..k*j
publicList getUserByName(String name)throws ^P}jn`4
d^(7\lw|
HibernateException { `i:DmIoz
String querySentence = "FROM user in class J^V}%N".
s ]XZQr%
com.adt.po.User WHERE user.name=:name"; /
:z<+SCh
Query query = getSession().createQuery 9Gc4mwu
~9 [O'
(querySentence); Ht9QINo
query.setParameter("name", name); *t%Z'IA
return query.list(); [`4
} iLC.?v2=
yCvP-?2
/* (non-Javadoc) ?l9j]
* @see com.adt.dao.UserDAO#getUserCount() -Is;cbfLj/
*/ j"F?^0aR,Q
publicint getUserCount()throws HibernateException { I?&/J4o:
int count = 0; 8v }B-cS
String querySentence = "SELECT count(*) FROM RH}i=
DEw>f%&4
user in class com.adt.po.User"; tP][o494\&
Query query = getSession().createQuery B%^W$7
q
bt{b%r
(querySentence); /wI"oHZd
count = ((Integer)query.iterate().next *671MJ9
akA7))Q
()).intValue(); xt&4]M
V
return count; ?Qxf~,F
} kz\Ss|jl
AxtmG\o>
/* (non-Javadoc) YO'aX
* @see com.adt.dao.UserDAO#getUserByPage QdrZi.qKH
21$E.x 6
(org.flyware.util.page.Page) <I#nwoHN
*/ {sfA$ d0
publicList getUserByPage(Page page)throws 6Hp+?mmh
-3K01p
HibernateException { hYht8?6}m
String querySentence = "FROM user in class g\% Z+Dc
F)Iz:
com.adt.po.User"; )_YB8jUR-X
Query query = getSession().createQuery rJ)j./c
} J[Z)u
(querySentence); jsFfrS"*
query.setFirstResult(page.getBeginIndex()) apOa E7|
.setMaxResults(page.getEveryPage()); *4ido?
return query.list(); H76iBJ66
} PjD9D.
p0[+Zm{#l
} bksv2@ar
Fw S>V2R
5a-x$Qb9
W,|+Dl
vc :%
至此,一个完整的分页程序完成。前台的只需要调用 VsJiE0'%
" Lh&s<[
userManager.listUser(page)即可得到一个Page对象和结果集对象 57~y 7/ 0
w_f.\\1r
的综合体,而传入的参数page对象则可以由前台传入,如果用 cNbUr
WfD fj
webwork,甚至可以直接在配置文件中指定。 P)kJ[Zv>f
DXo]O}VF
下面给出一个webwork调用示例: _jc_(;KPF
java代码: Vr|e(e.%
-p>~z )
D#AqZS>B
/*Created on 2005-6-17*/ Y
hQ)M5
package com.adt.action.user; zXM,cV/s
>.6|\{*sG
import java.util.List; f~F{@),acZ
nTv}/M&
import org.apache.commons.logging.Log; vQ
L$.A3>
import org.apache.commons.logging.LogFactory; PcBD;[cn
import org.flyware.util.page.Page; 7o0zny3?
!b"?l"C+u
import com.adt.bo.Result; sO`
oapy
import com.adt.service.UserService; n>?D-)g
import com.opensymphony.xwork.Action; jQ,Vs=*H
Kxch.$hc,
/** V"Z8-u
* @author Joa n m<?oI*\
*/ =gs-#\%
publicclass ListUser implementsAction{ (-g*U#
1$8@CT^m
privatestaticfinal Log logger = LogFactory.getLog Z2gWa~dBC
{nbT$3=Zt
(ListUser.class); <)p.GAZ
Lo~;pvv
private UserService userService; 1_<x%>zG
59O-"Sc[
private Page page; vjq2(I)u
0|RofL&o
privateList users; Km;}xke6
=KUmvV*\
/* ICb!AsL
* (non-Javadoc) #n'.a1R
* >UMxlvTg&
* @see com.opensymphony.xwork.Action#execute() yo=L1;H
*/ a8f#q]TyQ
publicString execute()throwsException{ |82q|@e
Result result = userService.listUser(page); d?8OY
page = result.getPage(); !JDr58
users = result.getContent(); W|7|XO
return SUCCESS; \c
-m\|
} HiA E9
`^Vd*
/** w.-x2Zg},
* @return Returns the page. _"ciHYHBQ
*/ cvaG[NF
public Page getPage(){ l[Z o,4*
return page; uhh7Ft#H
} Y>8Qj+d
N#K)Z5J)b
/** /@F'f@;
* @return Returns the users. lN#j%0MaUo
*/ ==OUd6e}
publicList getUsers(){ >jX"
return users; &t^*0/~
} `9co7[Z
(N}-]%#
/** !?nO0Ao-$
* @param page [(heE
* The page to set. `qc"JB
*/ r8s>s6vm
publicvoid setPage(Page page){ fAgeF$9@
this.page = page; rO7_K>g?
} u%~'+=
)2Ei<
/** hOwb
* @param users `(FjOd
K
* The users to set. gsbr8zwG,
*/ =&z+7Pe[
publicvoid setUsers(List users){ 2y
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this.users = users; &VGV0K3Dp
} uu.X>agg
'4 *0Pw
/** <= o<lRU
* @param userService dd
* The userService to set. V: D;?$Jl
*/ "V' r}>
publicvoid setUserService(UserService userService){ &DWSf`:Hx
this.userService = userService; +]eG=.
u
} M-nRhso
} i1cd9
/oT~CB..
^2~ZOP$A
1
pVw,}
q[\ 3,Y
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, I?'*vAW<
h9QM
nH'
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 4Hz3KKu
yv4x.cfI2W
么只需要: I{89chi
java代码: < o?ua}
8J3#(aBm
|Q/LC0?
<?xml version="1.0"?> t`8Jz~G`
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork R4'.QZ-x
3+Lwtb}XPF
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Gd
4S7JE
f6Y?),`
1.0.dtd"> th{f|fm62
G3_7e A#;
<xwork>
=`3r'c
l ms^|?
<package name="user" extends="webwork- i{fw?))+
=MqEbQn{C3
interceptors"> D`p2a eI
RnkV)ed(
<!-- The default interceptor stack name zIF1A*UH
%@PcQJg U<
--> ~rV $.:%va
<default-interceptor-ref [)I^v3]U
S%\5"uGa
name="myDefaultWebStack"/> +ywz@0nx
jr`T6!\
<action name="listUser" ]Ozz"4Z
E{Wn&?i>A
class="com.adt.action.user.ListUser"> k9
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<param c +]r
I0F[Z\U
name="page.everyPage">10</param> u.2X"
<result k{f1q>gd
f!+d*9
name="success">/user/user_list.jsp</result> "q?(rx;
</action> K}cZK
$*{,Z<|2
</package> |B(,53
s]m]b#1!r
</xwork> TIp\-
tV=Qt[|@
~~{lIO)&