Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 !@5B:n*
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 E{|j
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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 F~4oPB K<
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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 cjp
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分页支持类: a|{RK}|3
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java代码: qE!.C}L+
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package com.javaeye.common.util; 1r'skmxq
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import java.util.List; 8 Zhx&
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publicclass PaginationSupport { {L4ta~2/T
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publicfinalstaticint PAGESIZE = 30; C/U^8,6\n
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privateint pageSize = PAGESIZE; B^Fe.t y
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privateList items; 3%p^>D\
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privateint totalCount; 1#/>[B
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privateint[] indexes = newint[0]; x(ue
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privateint startIndex = 0; H}Z\r2
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public PaginationSupport(List items, int t Y'fFz^Ho
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totalCount){ Bs:INvhYW
setPageSize(PAGESIZE); R9xhO!
setTotalCount(totalCount); #0GvL=}k
setItems(items); * `1W})
setStartIndex(0); ~|QhWgq
} Wo+fMn(O
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public PaginationSupport(List items, int Rw-!P>S$
8&t3a+8l
totalCount, int startIndex){ xy;u"JY*
setPageSize(PAGESIZE); [+j}:u
setTotalCount(totalCount); pbJC A&
setItems(items); 9=YX9nP
setStartIndex(startIndex); lXso@TNrZ0
} =Kqb
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public PaginationSupport(List items, int ROqz$yY
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totalCount, int pageSize, int startIndex){
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setPageSize(pageSize); mqUn3F3
setTotalCount(totalCount); !g=4\C`mY
setItems(items); V'alzw7#
setStartIndex(startIndex); S+9}W/
} 7.}Vvg#G
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publicList getItems(){ I5Vp%mCY
return items; ,E
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} O1xK\ogv
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publicvoid setItems(List items){ *5T^wZpj)
this.items = items; H;D5)eJ90
} N=%4V
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publicint getPageSize(){ xw2dNJL
return pageSize; CvkZ<i){
} b%A+k"d
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publicvoid setPageSize(int pageSize){ meJ%mY
this.pageSize = pageSize; X3mHg5zt
} csK;GSp}
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publicint getTotalCount(){ P-]u&m/6
return totalCount; bSJ@
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} ,#?iu?i/
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publicvoid setTotalCount(int totalCount){ =2J^
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if(totalCount > 0){ -}:;
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this.totalCount = totalCount; V)<Jj
int count = totalCount / p#;I4d G
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pageSize; ; ,9:1.L
if(totalCount % pageSize > 0) XSOSy2:
count++; \k
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indexes = newint[count]; +V
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for(int i = 0; i < count; i++){ C!X"0]@FA
indexes = pageSize * "($"T v2
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} "WF@T
}else{ (Y!{ UNq5
this.totalCount = 0; +YD_ L
} 0)Nu
} +%sMd]$,n
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publicint[] getIndexes(){ nY M2Vxi0+
return indexes; ){}1u ?
} lD9QS ;
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publicvoid setIndexes(int[] indexes){
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this.indexes = indexes; K&'Vd@
} , ;$SRQ.
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publicint getStartIndex(){ qe[P'\]L
return startIndex; (ay((|)
} >}H3V]
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publicvoid setStartIndex(int startIndex){ [x[nTIg
if(totalCount <= 0) ;)Fc@OXN>
this.startIndex = 0; $Cnv]1%
elseif(startIndex >= totalCount) X+7@8)1(
this.startIndex = indexes Qo\+FkhYq
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[indexes.length - 1]; 3Z_\.Z1R@
elseif(startIndex < 0) +?9.
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this.startIndex = 0; 7MZ(tOR
else{ 328gTP1
this.startIndex = indexes D;! aix3
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[startIndex / pageSize]; Q ym=L(X
} ,z5B"o{Et
} LS%;ZKJ
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publicint getNextIndex(){ 1| XC$0
int nextIndex = getStartIndex() + |SX31T9rG
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pageSize; S; Fj9\2)I
if(nextIndex >= totalCount) wX+KW0|>
return getStartIndex(); jJqq:.XqB8
else )0XJOm
return nextIndex; wl5+VC*l0
} "30R%oL]=
ab8F\%y-8
publicint getPreviousIndex(){ ;d<RPVE:
int previousIndex = getStartIndex() - sjj,q?
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pageSize; L %20tm
if(previousIndex < 0) UPcx xtC
return0; {?uG] G7
else ZTzh[2u*
return previousIndex; y^}00Z+l
} 7El :$H
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} )-\[A<(
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抽象业务类 l*-$H$
java代码: (W'3Zv'f
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/** WUK{st.z
* Created on 2005-7-12
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*/ ^oXLk&d
package com.javaeye.common.business; OM (D@up
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import java.io.Serializable; |PutTcjQ
import java.util.List; ~JX+4~qT
T :0#se
import org.hibernate.Criteria; F.$NYr/|y
import org.hibernate.HibernateException; V9/P kuT
import org.hibernate.Session; v%8S:3
import org.hibernate.criterion.DetachedCriteria; ZIp"X
import org.hibernate.criterion.Projections; z;1qYW[-A
import 8)V6yKGO
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org.springframework.orm.hibernate3.HibernateCallback; js F96X{
import &XZS}n
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org.springframework.orm.hibernate3.support.HibernateDaoS HwxME%w
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upport; !cA4erBP
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import com.javaeye.common.util.PaginationSupport; |#J!oBS!
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public abstract class AbstractManager extends M?.[Rr-uw
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HibernateDaoSupport { us >$f20T
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privateboolean cacheQueries = false; cUD}SOW
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privateString queryCacheRegion; 't#E-+o
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publicvoid setCacheQueries(boolean TKrh3
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cacheQueries){ s^>1rV]=(`
this.cacheQueries = cacheQueries; ?X~U[dV?
} &? z6f9*$
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publicvoid setQueryCacheRegion(String R6E.C!EI
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queryCacheRegion){ /2fQM_ ,P
this.queryCacheRegion = 97\9!)`,
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queryCacheRegion; c5AEn -Q
} L%5g]=
}1?
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publicvoid save(finalObject entity){ /5r!Fhx
getHibernateTemplate().save(entity); yQdoy^d/4
} I1fUV72
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publicvoid persist(finalObject entity){ 3}V-'!
getHibernateTemplate().save(entity); cRS2v--\-
} 3!2TE -
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publicvoid update(finalObject entity){ HiPd|D
getHibernateTemplate().update(entity); 'bx$}w N
} HWxwG'EEY,
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publicvoid delete(finalObject entity){ IrTMZG
getHibernateTemplate().delete(entity); f) @-X!
} ^gd[U C-"w
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publicObject load(finalClass entity, jLCZ
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finalSerializable id){ [RFF&uy
return getHibernateTemplate().load \8iWcqJktN
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(entity, id); r0fEW9wL
} " twq#Alx
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publicObject get(finalClass entity, >q^l
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finalSerializable id){ qgk6 \&K[
return getHibernateTemplate().get %eQw\o,a
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(entity, id); W=ar&O~}n
} ;=F]{w]$+
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publicList findAll(finalClass entity){ 4pC.mRu
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return getHibernateTemplate().find("from >Z&Y!w'A|u
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" + entity.getName()); FCPiU3
} (|_N2R!
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publicList findByNamedQuery(finalString uwhb-.w
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namedQuery){ 9Netnzv%
return getHibernateTemplate 2}8xY:|@(U
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().findByNamedQuery(namedQuery); s6.#uT7h
} zpM%L:S
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publicList findByNamedQuery(finalString query, k-XE|v
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finalObject parameter){ KL4vr|i,
return getHibernateTemplate ?R8wm E[w
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().findByNamedQuery(query, parameter); q;L~5q."E
} ^L +@oS
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publicList findByNamedQuery(finalString query, 8e*1L:oB!
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finalObject[] parameters){ ZA
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return getHibernateTemplate VMb r@9
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().findByNamedQuery(query, parameters); uIb,n5
} M qG`P
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publicList find(finalString query){ Ql.abU
return getHibernateTemplate().find i_kKE+Q
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(query); FatLc|[
} +`s%-}-r
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publicList find(finalString query, finalObject P_8z'pYd>
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parameter){ Uf<hzP
return getHibernateTemplate().find {B,r
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(query, parameter); QfHO3Y6h[
} MPI=^rc2
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public PaginationSupport findPageByCriteria ;Uv/#"r
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(final DetachedCriteria detachedCriteria){ U-0A}@N
return findPageByCriteria ^;=L|{Xl
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); %?WR9}KU0
} i>}aQ:&^0
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public PaginationSupport findPageByCriteria :d ,]BB
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(final DetachedCriteria detachedCriteria, finalint qTD^Vz
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startIndex){ Ccx1#^`
return findPageByCriteria ?N/6m
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(detachedCriteria, PaginationSupport.PAGESIZE, `7mRUDz
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startIndex); k;W`6:Kjp
} UoSzxL
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public PaginationSupport findPageByCriteria W`2Xn?g
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(final DetachedCriteria detachedCriteria, finalint n13#}i{tm
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pageSize, wSwDhOX=
finalint startIndex){ YN >k5\M_v
return(PaginationSupport) MrGq{,6C
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getHibernateTemplate().execute(new HibernateCallback(){ XwNJHOaF
publicObject doInHibernate 5B76D12
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(Session session)throws HibernateException { JX! @j3
Criteria criteria = &3t[p=
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detachedCriteria.getExecutableCriteria(session); Nt5`F@;B
int totalCount = Hz6tk9;w
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((Integer) criteria.setProjection(Projections.rowCount GL<u#[
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()).uniqueResult()).intValue(); iF#|Z$g-(
criteria.setProjection 2V6kCy@V
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(null); mIy|]e`SJ
List items = 8\H*Z2yF+
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criteria.setFirstResult(startIndex).setMaxResults 8nSEAr~
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(pageSize).list(); yy*8Aw}
PaginationSupport ps = CfMCc:8mL
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new PaginationSupport(items, totalCount, pageSize, 2/ES.>K!.
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startIndex); UG5AFZ\
return ps; "ytPS~
} m:
}, true); _hz}I>G@B
} V~%C me
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public List findAllByCriteria(final 5zf bI
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DetachedCriteria detachedCriteria){ 6";ew:Ih^
return(List) getHibernateTemplate bCbp JZ
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().execute(new HibernateCallback(){ jr`;H
publicObject doInHibernate U-mZO7y!
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(Session session)throws HibernateException { NQpC]#n
Criteria criteria = G9
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detachedCriteria.getExecutableCriteria(session); vi1
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return criteria.list(); Xvr7qowL
} 4v?}K
}, true); pcrarj
} cKM#0dq
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public int getCountByCriteria(final &h<\jqN/
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DetachedCriteria detachedCriteria){ wS"`~Ql_
Integer count = (Integer) Dm+[cA"I
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getHibernateTemplate().execute(new HibernateCallback(){ Q dPqcw4+X
publicObject doInHibernate H,q-*Kk
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(Session session)throws HibernateException { [0M`uf/u
Criteria criteria = oH]_2[
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detachedCriteria.getExecutableCriteria(session); 5ca!JLs
return CAT{)*xc
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criteria.setProjection(Projections.rowCount N7 ox#=g
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()).uniqueResult(); Svl;Ul
} =73aME}
}, true); h; "pAE
return count.intValue(); Hq;*T3E
} UrRYK-g
} q*'-G]tH=
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用户在web层构造查询条件detachedCriteria,和可选的 B{hV|2
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ]]^r)&pox
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PaginationSupport的实例ps。 &y&pjo6v1
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ps.getItems()得到已分页好的结果集 i[4t`v'Dk
ps.getIndexes()得到分页索引的数组 K3.z>.F'h
ps.getTotalCount()得到总结果数 k@
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ps.getStartIndex()当前分页索引 `P/87=h
ps.getNextIndex()下一页索引 ^9zlxs`<d
ps.getPreviousIndex()上一页索引 ZuNUha&a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ecMpU8}rR
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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 q${+I(b,
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一下代码重构了。 49tJ+J- N
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我把原本我的做法也提供出来供大家讨论吧: 7TB&Q*Zf
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首先,为了实现分页查询,我封装了一个Page类: sUk&NM%>
java代码: =J0r,dR
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/*Created on 2005-4-14*/ 95.s,'0
package org.flyware.util.page; t; b1<TLn0
5;CqGzgoP
/** #Fckev4
* @author Joa B,4
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* jP31K{G?
*/ MZ:Ty,pw:O
publicclass Page { lGXr-K?+Y
lFV\Go
/** imply if the page has previous page */ Sd *7jW?
privateboolean hasPrePage; *(o^w'5
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/** imply if the page has next page */ 4hWFgk
privateboolean hasNextPage;
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"P!zu(h4
/** the number of every page */ ekCt1^5Y
privateint everyPage; &\W5|*`x-
YDaGr6y4i
/** the total page number */ $]~|W3\G
privateint totalPage; $xK(bc'{
, GMuq_H
/** the number of current page */ 49Hgq/uO
privateint currentPage; ~)#xOE}
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/** the begin index of the records by the current *qKf!&
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query */ f!bGH-.r5
privateint beginIndex; :MILOwF
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/** The default constructor */ 2>vn'sXdj
public Page(){ B&sa|'0U
-ze@~Z@
} NC%)SG \
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/** construct the page by everyPage yJ2A!id
* @param everyPage ,ik\MSS
* */ )AXa.y
public Page(int everyPage){ 2$O6%0
this.everyPage = everyPage; :9W)CwZ)V
} W:1GY#Pe
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/** The whole constructor */ 66'AaA;0^i
public Page(boolean hasPrePage, boolean hasNextPage, ~-BIUZ;
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v;:. k,E0
int everyPage, int totalPage, tRXR/;3O
int currentPage, int beginIndex){ 2l}3L
this.hasPrePage = hasPrePage; 0c]3 ,#
this.hasNextPage = hasNextPage; $Hal]
this.everyPage = everyPage; ;op8r u
this.totalPage = totalPage; W_ubgCB
this.currentPage = currentPage; *h2)$^P%
this.beginIndex = beginIndex; #6za
} ("_tML 8/p
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/** }zqYn`ffD
* @return Q*caX
* Returns the beginIndex. Jtl[9qe#]
*/ 8\rHSsP
publicint getBeginIndex(){ QW6\~l 4
return beginIndex; 6Ej@;]^^-
} xyRZ
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/** ?iaD;:'qE
* @param beginIndex S1W(]%0/
* The beginIndex to set. -{a&Zkz>V
*/ v`9n'+h-c6
publicvoid setBeginIndex(int beginIndex){ <rFKJ^ B
this.beginIndex = beginIndex; J2Eb"y>/;
} Pt8 U0)i)
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/** "~aCW~
* @return }|4dEao\
* Returns the currentPage. VD- 2{em
*/ ^FN(wvqb8
publicint getCurrentPage(){ ;c;PNihg
return currentPage; 9Sk?tl
} 4O'X+dv^I
o;2QZ"v
/** pm}!?TL
* @param currentPage >$p|W~x
* The currentPage to set. 4O** %!|
*/ ,1&</R_
publicvoid setCurrentPage(int currentPage){ -A17tC20J1
this.currentPage = currentPage; E0a &1j
} I:G4i}mA
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/** q(I`g;MF
* @return p@+r&Mg%W"
* Returns the everyPage. B
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*/ 6_h'0~3?`
publicint getEveryPage(){ >g FEA0-
return everyPage; ]EZiPW-uy
} \,5OPSB
c})f&Z@<
/** jsOid5bs
* @param everyPage BNe6q[ )W~
* The everyPage to set. !*@sX7H
*/ `c~J&@|
publicvoid setEveryPage(int everyPage){ zs~v6y@
this.everyPage = everyPage; bI"_hvcFp
} v8!Ts"
lboi\GP|
/** I?_YL*
* @return j6_tFJT
* Returns the hasNextPage. nD51,1>
*/ UfWn\*J&k
publicboolean getHasNextPage(){ T,D(Xh
return hasNextPage; ^$I8ga
} ckTk2xPQ
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/** da/Tms`T
* @param hasNextPage wfXm(RYM
* The hasNextPage to set. ?]]d
s]
*/ nF!6
publicvoid setHasNextPage(boolean hasNextPage){ bYKe5y=
this.hasNextPage = hasNextPage; n$oHr
} 9Oe~e
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/** ?' :v):J}
* @return LnZC)cL
P/
* Returns the hasPrePage. }[>X}"_e
*/ U$,W/G}m
publicboolean getHasPrePage(){ Lm{qFu
return hasPrePage; $)O=3dNbo
} q&RezHK l
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/** R]! [h
* @param hasPrePage -)p
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* The hasPrePage to set. rV0X*[]J>
*/ t/57LjV
publicvoid setHasPrePage(boolean hasPrePage){ }pMd/|A,
this.hasPrePage = hasPrePage; 9 cwy;au
} Z=&cBv4Fs
F?B`rw@xr
/** Qmg2lP.)
* @return Returns the totalPage. ^f%hhpV@
* Sb& $xWL
*/ y9xvGr[l
publicint getTotalPage(){ W#.+C6/
return totalPage; 4,]z
} {%b*4x0?
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/** qTuQ]*[-
* @param totalPage miTySY6^
* The totalPage to set.
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*/ <n-}z[09
publicvoid setTotalPage(int totalPage){ 'C2X9/!,
this.totalPage = totalPage; s9)U",
} O DO'!T-
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} :+qd>;yf#
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 MoX~ZewWR
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个PageUtil,负责对Page对象进行构造: {)?:d6"
java代码: 9k.5'#
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/*Created on 2005-4-14*/ x,% %^(
package org.flyware.util.page; a7@':Rb n
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import org.apache.commons.logging.Log; /L yoTBG
import org.apache.commons.logging.LogFactory; BtA_1RO
Rl/5eE8
/** 5w+KIHhN|
* @author Joa r&y0`M
* 31^Jg
*/ /f}!G
publicclass PageUtil { je`Ysbe n
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privatestaticfinal Log logger = LogFactory.getLog VchI0KL?
4Y5lP00!}
(PageUtil.class); |8q:sr_
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/** Oo0SDWI`(
* Use the origin page to create a new page !7hjA=0
* @param page
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* @param totalRecords e=^^TX`I
* @return mfqnRPZ
*/ ;0vCZaEF
publicstatic Page createPage(Page page, int L~+/LV
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totalRecords){ ~jR4%VF
return createPage(page.getEveryPage(), qipV'T,S
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page.getCurrentPage(), totalRecords); FMi:2.E
} ,r8#-~A6,A
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/** g7"2}|qxo
* the basic page utils not including exception hm*cGYV/
ZuFcJ?8i
handler ZXIw^!8@/
* @param everyPage M>_vsI^I'
* @param currentPage u*T(n s
l
* @param totalRecords SK*z4p
* @return page U4.$o]58
*/ v YJ9G"E
publicstatic Page createPage(int everyPage, int kV+%(Gl8
Mbp7%^E"A
currentPage, int totalRecords){ Q+oV?
S3{
everyPage = getEveryPage(everyPage); %s! |,Cu
currentPage = getCurrentPage(currentPage); s IFE:/1,
int beginIndex = getBeginIndex(everyPage, ;1HzY\d%<
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currentPage); *`q?`#1&&.
int totalPage = getTotalPage(everyPage, \xlG 3nz
<2E|URo,#
totalRecords); A;<wv>T
boolean hasNextPage = hasNextPage(currentPage, {h=gnR-9
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totalPage); T]JmnCX>:
boolean hasPrePage = hasPrePage(currentPage); nwp(% fBo
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returnnew Page(hasPrePage, hasNextPage, &7i&"TNptP
everyPage, totalPage, Sx[
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currentPage, q3<kr<SP
ua)jGif
beginIndex); F"bz<{
} q)mG6Su
d
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privatestaticint getEveryPage(int everyPage){ 9O- 2
return everyPage == 0 ? 10 : everyPage; Wqkb1~]#Y
} Q~tXT_
ruQt0q,W3%
privatestaticint getCurrentPage(int currentPage){ RC/45:hZZ
return currentPage == 0 ? 1 : currentPage; lxm/*^
} tYXE$i
8PzGUn;\
privatestaticint getBeginIndex(int everyPage, int :\vs kk),
(Vr%4Z8
currentPage){ CxTmW5l
return(currentPage - 1) * everyPage; |mP};&b
} 3 3|t5Ia
{vGJ}q?Sd"
privatestaticint getTotalPage(int everyPage, int 8Z0x*Ssk
m`9nDiV
totalRecords){ &iInru3
int totalPage = 0; +ID\u
<?
0:`|T jf_
if(totalRecords % everyPage == 0) >v %js!`f
totalPage = totalRecords / everyPage; ?+))J~@t
else g"Y_!)X
totalPage = totalRecords / everyPage + 1 ; mwo:+^v(
+]s,VSL5`
return totalPage; `XhH{*Q"X
} 4SZ,X^]I>
t|$jgM
privatestaticboolean hasPrePage(int currentPage){ ejlns
~
return currentPage == 1 ? false : true; c3 O/#*
} N^dQX,j
H;
NV?CD
privatestaticboolean hasNextPage(int currentPage, <@<bX
R>*z8n
int totalPage){ }! EVf
return currentPage == totalPage || totalPage == )Cl>% 9
E=N$JM
0 ? false : true; Y>8Qj+d
} mUa#sTm
dMH_:jb
kU[hB1D5
} >UvP/rp
`*3A7y
/[<F
f
2ZY$/
^Hv&{r77
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。 px<psR5
Lw}-oE
!U
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 T82 `-bZ
TKR#YJQ?K
做法如下: $<v4c5r]O
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 dS ojq6M
q<
XFw-Pv
的信息,和一个结果集List: \ZZ6r^99
java代码: 5c` ;~
AH#mL
uQIPnd(V
/*Created on 2005-6-13*/ ?>}p'{I
package com.adt.bo; Nvgi&iBh8
i%-yR DIX
import java.util.List; Q>, &@
z2iMpZ
import org.flyware.util.page.Page; }PBme'kP
;OlnIxH(W
/** 1'qXT{f/~
* @author Joa ~.:{
Ik]
*/ :C*}Yg
publicclass Result { 9wYm(7M6
~_fc=^o
private Page page; wa8jr5/k"
a9-Mc5^'n
private List content; NPK;
M0w Uis:`
/** = LNU%0m
* The default constructor qWhW4$7x
*/ Rn~'S2`u
public Result(){ YVMvT>/,
super(); 5@2Rl>B$
} g8Ex$,\,
.;4N:*hY
/** 9^XZ|`
* The constructor using fields ^I!Z)/
* :}e<
* @param page |M;Nq@bRv
* @param content gw)4P tb!
*/ f)*?Ji|5F
public Result(Page page, List content){ vwT1bw .
this.page = page; J@2jx4
this.content = content; Zi~.
} 1eD#-tzV
pTCD1)
/** K=N&kda
* @return Returns the content. dHDtY$/_
*/ 3gUY13C}:p
publicList getContent(){ V
*@q< rQ
return content; ^*}D*=>\
} 7Mh'x:p
28"1ONs3
/** p& _Z}Wv
* @return Returns the page. n+8YTjd
*/ +j 9+~
public Page getPage(){ N|yA]dg[
return page; VeWh9:"bJ
} *:CTIV5N0
8xLQ"
l+"
/** *|y'%y
* @param content ww{k_'RRJ
* The content to set. z:-{Y2F
*/ GJB+]b-
public void setContent(List content){ u&l;\w
this.content = content; gX{j$]^6G8
} Q#% LIkeq
SSI> +A
/** <.ZIhDiEl
* @param page }rJqMZ]w
* The page to set. 6|EOB~|
*/ i3)3.WK^
publicvoid setPage(Page page){ jwk+&S
this.page = page; 8XH;<z<oJ
} E:9RskI
} &}u_e`A
w:
BJ4bi=
._0$#J S[
5S4Nx>
X?haHM#]
2. 编写业务逻辑接口,并实现它(UserManager, /R B%m8@;
%`bs<ZWT
UserManagerImpl) %Ik5|\ob?
java代码: JYc:@\
s]m]b#1!r
%72# tY
/*Created on 2005-7-15*/ (Iv@SiZf(
package com.adt.service; ~aotV1"D
#X)DFAtb
import net.sf.hibernate.HibernateException; 9BakxmAc
,O:4[M !$w
import org.flyware.util.page.Page; C/!P&`<6
<W!T+sMQj
import com.adt.bo.Result; >7WT4l)7!b
iX?j "=!
/** O.dZ3!!+
* @author Joa !*c%Dj
*/ !S<p"
publicinterface UserManager { |}77'w :
'@ 24<T]
public Result listUser(Page page)throws k
x:+mF
8;qOsV)UDT
HibernateException; mg*iW55g
!"hlG^*9
} Z84w9y7O<
d*TH$-F!p
yHY2 SXm
_Q #[IH9
HHx5VI
java代码: ]fY:+Ru
:LuA6
&v]xYb)+<
/*Created on 2005-7-15*/ 6<z#*`U1
package com.adt.service.impl; jXx~5
/\ fR6|tJ
import java.util.List; sB0]lj-[Un
fbI5!i#lz
import net.sf.hibernate.HibernateException; iw.F8[})
"U9e)a0v
import org.flyware.util.page.Page; ~e|E5[-i
import org.flyware.util.page.PageUtil; <YCjo[(~
*=md!^x`
import com.adt.bo.Result; xz`0V}dPl
import com.adt.dao.UserDAO; g1XpERsSEV
import com.adt.exception.ObjectNotFoundException; JSFNn]z2P
import com.adt.service.UserManager; Zq{gp1WC
#}1yBxB<=
/** :tENn
r.9v
* @author Joa ([m4dr
*/ <OiH%:G/1
publicclass UserManagerImpl implements UserManager { ke6,&s%{j
5aVZ"h"
private UserDAO userDAO; ?z.
Z_A&
Z{u]qI{l
/** `m V(:
* @param userDAO The userDAO to set. bz:En'2>F
*/ DFwiBB6
publicvoid setUserDAO(UserDAO userDAO){ r{~b4~kAf5
this.userDAO = userDAO; uGC%3!f!
} 2x gk$E$ 7
5> 81Vhc,
/* (non-Javadoc) M3eSj`c3
* @see com.adt.service.UserManager#listUser ,H|K3nh
pw))9~XU
(org.flyware.util.page.Page) u$qasII
*/ VaonG]Ues
public Result listUser(Page page)throws ;Zf7|i`R3
<'T DOYb
HibernateException, ObjectNotFoundException { 9AWP`~l`
int totalRecords = userDAO.getUserCount(); ']!wc8m1"
if(totalRecords == 0) [$6YPM>Ee
throw new ObjectNotFoundException ;Gp9
? 0
}w=|"a|,
("userNotExist"); a'q&[08
page = PageUtil.createPage(page, totalRecords); {h|kx/4{m
List users = userDAO.getUserByPage(page); IM,d6lN6s
returnnew Result(page, users); >z3l@
} nr>Yj?la
0#5&*
} ZXj*Vu$_4
-f'&JwE0=
6R2F,b(_
MO1H?Uhx
=BD|uIR
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 E.B6u, Te
A'uubFRL2[
询,接下来编写UserDAO的代码: cr18`xU
3. UserDAO 和 UserDAOImpl: IUWJi\,
java代码: PE_JO(e;Xm
n-?zH:]GG{
ZP:+ '\&J
/*Created on 2005-7-15*/ uxX 3wY;M
package com.adt.dao; \R
3O39[
>kuu\
import java.util.List; Vo%ikR #
juWbd|ad"
import org.flyware.util.page.Page; ?>R(;B|ER
&?j\=%
import net.sf.hibernate.HibernateException; $|@-u0sv
>qMzQw2
/** R-k~\vCW
* @author Joa 7 /"Z/^
*/ =FAIbM>u
publicinterface UserDAO extends BaseDAO { (76tYt~I=
OJFWmZ(X
publicList getUserByName(String name)throws zq$0 ?vGd
%4wHiCOg
HibernateException; @E> rqI;`
i_y%HG
publicint getUserCount()throws HibernateException; R2Q1Rk#
d|sf2
publicList getUserByPage(Page page)throws *]Eyf")
)ItW}1[I
HibernateException; e\ZV^h}TQ
Vc8w[oS
} IR8qFWDZ
wO]H+t
?%T]V+40
;|,*zD
K7,Sr1O `
java代码: 1_mqPMm
@><8YN^)%
*"V) hI5
/*Created on 2005-7-15*/ 2\"T&
package com.adt.dao.impl; [KEw5-=i@
7#PQ1UWl
import java.util.List; ~qE:Nz0@
#,SPV&
import org.flyware.util.page.Page; ka$la;e3
WXa<(\S\V
import net.sf.hibernate.HibernateException; k7nke^,|
import net.sf.hibernate.Query; k4JTc2b
@n$/2y_.
import com.adt.dao.UserDAO;
d-I&--"ju
+@+*sVb
/** -{p~sRc&
* @author Joa 5QG?*Z~?7
*/ dlDO?T
public class UserDAOImpl extends BaseDAOHibernateImpl (I#3![q
:>3?|Z"Aj
implements UserDAO { p%+'iDb
N1JM[<PP
/* (non-Javadoc) ' $"RQ=
* @see com.adt.dao.UserDAO#getUserByName nz/cs n
._6Q "JAB
(java.lang.String) `>HrO}x^
*/ S3y('
PeF
publicList getUserByName(String name)throws GjX6noqT
V?n=yg
HibernateException { CE|rn8MB
String querySentence = "FROM user in class 9bUFxSH
~Vf
A
com.adt.po.User WHERE user.name=:name"; iE^=Vf;
Query query = getSession().createQuery p<\7" SB=
zCmx 1Djz
(querySentence); n"Wlfd0
query.setParameter("name", name); \$xj>b;
return query.list(); CTQJ=R"
} }`+9ie7]/
Fzy5k?R
/* (non-Javadoc) bg^<e}{<H
* @see com.adt.dao.UserDAO#getUserCount() D/Py?<n-B
*/ [6\b(kS+
publicint getUserCount()throws HibernateException { gCx#&aXS
int count = 0; A(+%DZ
String querySentence = "SELECT count(*) FROM aqv'c
j>
[=^Wj`;
user in class com.adt.po.User"; Yb%#\.M/y
Query query = getSession().createQuery vU9:`@beu
8Y/1+-
(querySentence); )D&xyC}
count = ((Integer)query.iterate().next |u+!CR
HbJ^L:/
()).intValue(); 9u%(9Ae
return count; Dv~jVI Xu
} @DSKa`
!1/F71l DX
/* (non-Javadoc) +9B .}t#
* @see com.adt.dao.UserDAO#getUserByPage `pqTiV
gzN51B =D
(org.flyware.util.page.Page) r'MA$PiS'
*/ _Sl3)
publicList getUserByPage(Page page)throws &mm!UJ
QSOG(}w
HibernateException { 9A *gW j
String querySentence = "FROM user in class ]D,\(|
-L!lJ
com.adt.po.User"; x
kdC-S
Query query = getSession().createQuery d-TpY*v
o_03Io
~Bf
(querySentence); \susLD
query.setFirstResult(page.getBeginIndex()) R$;TX^r'o&
.setMaxResults(page.getEveryPage()); S:1g(f*85
return query.list(); ,(NN)Oj
} ~JO.h$1C
<jBRUa[j_
} @4n>I+6*&
Z}.ZTEB
Z{ 1B:aW
9+3 VK
[Kaa{+,(
至此,一个完整的分页程序完成。前台的只需要调用 %^[D+1ULb
/O~Np|~v
userManager.listUser(page)即可得到一个Page对象和结果集对象 B:Hr{%O
me-uPm
的综合体,而传入的参数page对象则可以由前台传入,如果用
m~uT8R#$
&^l(RBp]0
webwork,甚至可以直接在配置文件中指定。 13+.>
8 #:k
下面给出一个webwork调用示例: a4pe wg'
java代码: nkf7Fq}
7mE9Zo1
8{_lB#<[E
/*Created on 2005-6-17*/ gU1Pb]]
package com.adt.action.user; L@Q+HN
8 [D"
import java.util.List; qw{`?1[+
x_r*<?OZ
import org.apache.commons.logging.Log; hw(\3h()
import org.apache.commons.logging.LogFactory; B<0Kl.V
import org.flyware.util.page.Page; Sb(OG 6
h}kJ,n
import com.adt.bo.Result; -gUp/#l1
import com.adt.service.UserService; %Aqf=R_^
import com.opensymphony.xwork.Action; $lq.*UQ;0
SmIcqM
/** 4]6-)RHFB
* @author Joa +}PN+:yV
*/ Je}0KW3G9L
publicclass ListUser implementsAction{ +wxsAGy_j
c94=>p6
privatestaticfinal Log logger = LogFactory.getLog p}<60O"r$
?'_6M4UKa
(ListUser.class); gtePo[ZH.P
B9Hib1<8
private UserService userService; X0R EC%
e5
}amrz
private Page page; {`,)<R>}
dqs~K7O^E
privateList users; eze%RjO}
2=/-,kOL_
/* zTc*1(^
* (non-Javadoc) Qj*.Z4ue
* xF@&wg
* @see com.opensymphony.xwork.Action#execute() jFUpf.v2
*/ MpBdke$
publicString execute()throwsException{ FRQ0t!b<M1
Result result = userService.listUser(page); K6sXw[VC[
page = result.getPage(); w)`XM
users = result.getContent(); @\o"zU
return SUCCESS; I2Imb9k~B
}
|Wjpnz
cnI5G!
/** @bJIN]R
* @return Returns the page. 2`TV(U@
*/ xiDgQTDz
public Page getPage(){ 8;r #HtFM
return page; *0to,$ n
} i;-M8Q^
v?Utz~lQ
/** ^'a#FbMtt
* @return Returns the users. igW* {)h3
*/ |`t 6lVO,Z
publicList getUsers(){ X%3?sH
return users; H!&_Tv[
} Tjhy@3
cR_ pC
9z
/** D}LM(s3li7
* @param page OF+4Mq
* The page to set. n\3#69VY
*/ J=t}9.H~=
publicvoid setPage(Page page){ }ML2-k
this.page = page; &lLfVa-l
} U||GeEd
`;J`O02
/** M/dgW`c
* @param users vg1JN"S[
* The users to set. )*>wa%[-q
*/ cw{TS
publicvoid setUsers(List users){ y<E];ub
this.users = users; ?5J#
} 5l
3PAG
]B?M3`'>
/** Hd\V?#H
* @param userService V`1{*PrI@L
* The userService to set. U/^#nU.,
*/ 6]Is"3ca
publicvoid setUserService(UserService userService){ e-`.Ht
this.userService = userService; c|;n)as9(%
} UZ2_FP
} W>C?a=r~
f|FS%]fCxk
t4[q:[1
HyVV,q^E
ws+ '*7
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, ^`'\eEa
o+'|j#P
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 5P%#5Yr2
+tT"
么只需要: } &B6
java代码: ypx~WXFK
W.MZN4=
_huJ*W7lR
<?xml version="1.0"?> wW1VOj=6V"
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork {zvaZY|K"
m^}|LB:5
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Cl<!S`
P:4"~]}
1.0.dtd"> dAx
? ,
i[IFD]Xy!j
<xwork> Lo{wTYt:J
,"(G
<package name="user" extends="webwork- )>:~XA|?
A}(]J!rc
interceptors">
pE)NSZ
Ee2P]4_d
<!-- The default interceptor stack name "u!gfG?oH
dX cbS<
--> QQ .?A(U7
<default-interceptor-ref \ +%~7Bi]z
MmN{f~Kq9
name="myDefaultWebStack"/> XNWtX-[^@
e^>>"tr
<action name="listUser" ;+E]F8G9r
'7sf)0\:<p
class="com.adt.action.user.ListUser"> PJC(:R(j
<param <-`.u`
,%*UF6B
M
name="page.everyPage">10</param> BX0lk
<result $h{m")]
:^3 )[.m
name="success">/user/user_list.jsp</result> ;rT'~?q
</action> Y:ly x-lj
e=OHO,74z"
</package> $lJcC |*
/=m AVA
</xwork> (yqe4
DJ, LQj
i *.Y
>,{sFc
Q^Cm3|ZO
BqNeY<zB*
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 f47]gtB-
EVX3uC}{
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。 ju{Y6XJ)
B-rE8\
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 b?i+nhqI
CvY+b^ ;
g%f5hy
*#XZ*Ga
'6dVe2V
我写的一个用于分页的类,用了泛型了,hoho Snf_{A<
gM3:J:N
java代码: pX SShU#
"=Br&FN{|
1 P!)4W
package com.intokr.util;
[P`e@$
mZR3Hl$
import java.util.List; 6WY/[TC-
W\~^*ny
P6
/** ,IjZQ53q~
* 用于分页的类<br> qgrJi +WZ
* 可以用于传递查询的结果也可以用于传送查询的参数<br> U|}
?{x
* nnv|GnQST
* @version 0.01 q*3OWr
* @author cheng ?uq`| 1`
*/ gm-[x5O"
public class Paginator<E> { ]$@a.#}
privateint count = 0; // 总记录数 kcCCa@~v
privateint p = 1; // 页编号 ^HC6v;K
privateint num = 20; // 每页的记录数 6eV#x%z@v'
privateList<E> results = null; // 结果 EnM
$y8-JR~
/** 1D*=ZkA)
* 结果总数 1|MRXK
*/ ]y0Y (
publicint getCount(){ }<04\t?
return count; 'I]XX==_
} )!"fUz$
+-!E%$
publicvoid setCount(int count){ S\A/*!%~y
this.count = count; X2|~(*
} R@o&c%K"
'o-4'
/** ,QcS[9$
* 本结果所在的页码,从1开始 .G O0xnm
* a `R%\@1
* @return Returns the pageNo. MUrPr
*/ h@Q^&%w
publicint getP(){ 8<6H2~5<
return p; [SPx
} MVYd\)\o
*LEy#N
/** oACAC+CP
* if(p<=0) p=1 Nc:s+ o
* xLW$>;kI
* @param p ``-N2U5
*/ L'= \|r
publicvoid setP(int p){ u:l-qD9=(
if(p <= 0) entU+O r
p = 1; -'&/7e6>y
this.p = p; [;u#79aE
} MR#*/Iw~
za_b jE
/** ;+9OzF ;
* 每页记录数量 sK}AS;:
*/ Fv$tl)p*
publicint getNum(){ gQn%RPMh
return num; :$WO"HfMSn
} 'FErk~}/4s
%fj5;}E.
/** 6cH8Jr _
* if(num<1) num=1 ORExI.<`W
*/ }t H$:Z
publicvoid setNum(int num){ r]3-}:vU
if(num < 1) ]@{Lx>Oh"
num = 1; 2e`}O
this.num = num; IVR%H_uz
} 23}` e
jf9+H!?^N
/** y{ur'**l
* 获得总页数 en<~_|J
*/ P%3pM*.
publicint getPageNum(){ 8z9{H
return(count - 1) / num + 1; #{cy( &cz
} @aIgif+v
@5>#<LV=E#
/** cLtVj2Wb
* 获得本页的开始编号,为 (p-1)*num+1 /LD3Bb)O
*/ t3;Zx+Br
publicint getStart(){ }%|ewy9|CW
return(p - 1) * num + 1; J&xZN8jW
} .GrOdDK$ns
`/8@Fj
/** u^Q`xd1
* @return Returns the results. '75T2Ud
*/ i>m%hbAk
publicList<E> getResults(){ %*
"+kwZ
return results; >i/jqT/
} Tq1\
kaBjA*
public void setResults(List<E> results){ S_ATsG*(
this.results = results; B~]Kqp7yU
}
Gl~l
s)^/3a
public String toString(){ ={BD*=i
StringBuilder buff = new StringBuilder j q+(2
(80m'.X
(); s0SzO,Vi
buff.append("{"); 4#$#x=:
buff.append("count:").append(count); ]VI^ hhf
buff.append(",p:").append(p); ATs_d_Sz
buff.append(",nump:").append(num); K`4lL5oH
buff.append(",results:").append {r^_ g(.q
:Jd7q.
(results); 4V+bE$Wu
buff.append("}"); 1h,iWHC
return buff.toString(); /5@YZ?|#2
} &.)=>2
|2(q9j
} <:S qMf
dOhSqx56
+,Eam6g{