Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %p t^?
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 2.>aL
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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 {IgLH`@
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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 ]I<w;.z
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分页支持类: 3[Xc:;+/
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java代码: JV`"kk/
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package com.javaeye.common.util; F+ Dke>j
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import java.util.List; h7a/]~
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publicclass PaginationSupport { r>;(\_@
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publicfinalstaticint PAGESIZE = 30; #
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privateint pageSize = PAGESIZE; ya'Ma<4
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privateList items; &y&pjo6v1
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privateint totalCount; P|tNmv[;
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privateint[] indexes = newint[0]; /)*si
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privateint startIndex = 0; HrS-o=
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public PaginationSupport(List items, int #\l#f8(l
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totalCount){ C1w6[f1+
setPageSize(PAGESIZE); me
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setTotalCount(totalCount); U_C[9Z'P
setItems(items); O[j$n
setStartIndex(0); H.]p\UY9
} 044Q>Qz,
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public PaginationSupport(List items, int @>q4hYF
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totalCount, int startIndex){ Y;1s=B9
setPageSize(PAGESIZE); u-u:7VtH0=
setTotalCount(totalCount); U7xKu75G1
setItems(items); |<2<`3
setStartIndex(startIndex); J;S Z"I'
} t3<HE_B|
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public PaginationSupport(List items, int )u=46EU_
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totalCount, int pageSize, int startIndex){ hH]oJ}H \
setPageSize(pageSize); t; b1<TLn0
setTotalCount(totalCount); 5;CqGzgoP
setItems(items); >>T,M@s-:
setStartIndex(startIndex); #Fckev4
} B,4
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publicList getItems(){ PnJA'@x
return items; 4bq+(CI6
} xzb{g,c
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publicvoid setItems(List items){
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this.items = items; r"W<1Hu
} )&[Zw{6P
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publicint getPageSize(){ `,s0^?_
return pageSize; Mi<}q@]e
} V;(Rg=5
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publicvoid setPageSize(int pageSize){ o@qI!?p&
this.pageSize = pageSize; `^:
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} F>
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publicint getTotalCount(){ tN_~zP
return totalCount; kf1 (
} &GaI
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publicvoid setTotalCount(int totalCount){ , L5.KwB
if(totalCount > 0){ ]D@y""{--s
this.totalCount = totalCount; D6:"k
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int count = totalCount / ]ZS/9 $
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pageSize; keS%w]87
if(totalCount % pageSize > 0) DG/<#SCF
count++; U?8X]
indexes = newint[count]; U(\ ^!S1
for(int i = 0; i < count; i++){ l-q.VY2
indexes = pageSize * /jN&VpDG
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i; Dw&_6\F@
} 3gz4c1 s^:
}else{ Z`yW2ON$'
this.totalCount = 0; | (: PX
} [p96H)8YU
} }^ZPah
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publicint[] getIndexes(){ Y4)=D@JI
return indexes; 2^fSC`!
} u<nPJeE
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publicvoid setIndexes(int[] indexes){ to3D#9Ep
this.indexes = indexes; c59l/qoz
} d~w}{LR[1
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publicint getStartIndex(){ R|K#nh
return startIndex; ''wF%q
} ;op8r u
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publicvoid setStartIndex(int startIndex){ +$D~?sk
if(totalCount <= 0) f/]g@/`
this.startIndex = 0; qj<_*
elseif(startIndex >= totalCount) |^t8ct?x~
this.startIndex = indexes T0lbMp
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[indexes.length - 1]; /Avl&Rd
elseif(startIndex < 0) [ FNA:
this.startIndex = 0; X-J<gI(Y
else{ Ng1uJa[k!d
this.startIndex = indexes XkuZ2(
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[startIndex / pageSize]; >TwL&la
} P*6&0\af|
} MUqV$#4@I
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publicint getNextIndex(){ J2Eb"y>/;
int nextIndex = getStartIndex() + Pt8 U0)i)
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pageSize; a[Oi
if(nextIndex >= totalCount) X5wYfN
return getStartIndex(); Wj#Gm
else 5mF"nY&lI
return nextIndex; }|4dEao\
} AV^Sla7|_
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publicint getPreviousIndex(){ zIgD R
int previousIndex = getStartIndex() - J(%kcueb
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pageSize; *8j2iu-|
if(previousIndex < 0) P]||Xbbp
return0; l/@t>%
else Zv)x-48
return previousIndex; 8Qi@z Jq,
} x@480r
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} \D,c*I|p7
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抽象业务类
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java代码: Ee -yP[2
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/** xk$U+8K
* Created on 2005-7-12 cG~-OHU
*/ H}B%OFI \+
package com.javaeye.common.business; [_?dp aTt
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import java.io.Serializable; uQlQ%n%
import java.util.List; 0N19R 5NN8
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import org.hibernate.Criteria; %{ToWLb{I
import org.hibernate.HibernateException; C"!k`i=Lj
import org.hibernate.Session; dSm; e_s
import org.hibernate.criterion.DetachedCriteria; O6$d@r;EK]
import org.hibernate.criterion.Projections; &?gvW//L2
import 9WhZ=
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org.springframework.orm.hibernate3.HibernateCallback; #0;ULZ99aH
import yxz"9PE/P
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org.springframework.orm.hibernate3.support.HibernateDaoS PhOtSml0
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upport; 8Mf{6&F=
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import com.javaeye.common.util.PaginationSupport; R:t>PFwo
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public abstract class AbstractManager extends oyeJ"E2
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HibernateDaoSupport { EFNi# D8s
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privateboolean cacheQueries = false; 3.?kxac
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privateString queryCacheRegion; ij<6gv~ n"
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publicvoid setCacheQueries(boolean O>H'ok
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cacheQueries){ 96FS-`
this.cacheQueries = cacheQueries; GnzKDDH
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} ')mR87
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publicvoid setQueryCacheRegion(String yhpeP
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queryCacheRegion){ vz-O2B_u
this.queryCacheRegion = byTTLs,}d
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queryCacheRegion; ?|;q=p`t-
} vRQ7=N{3
#7}1W[y9}l
publicvoid save(finalObject entity){ y:R!E *.L'
getHibernateTemplate().save(entity); 86AZ)UP2D
} 7}2Aq
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publicvoid persist(finalObject entity){ {5,
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getHibernateTemplate().save(entity); _^5OoE"}!
} exHg<18WSe
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publicvoid update(finalObject entity){ b&j}f
getHibernateTemplate().update(entity); hmQ;!9
} L
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publicvoid delete(finalObject entity){ 0<";9qN)6
getHibernateTemplate().delete(entity); (q]_&%yW
} |r%NMw #y
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publicObject load(finalClass entity, =h
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finalSerializable id){ r$
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return getHibernateTemplate().load >{HQ"{Q
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(entity, id); UTLuzm
} 5u89?-UD
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publicObject get(finalClass entity, !|#W,9
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finalSerializable id){ w4fz!l]
return getHibernateTemplate().get P<5v\\
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(entity, id); <lo\7p$A
} W Y]
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publicList findAll(finalClass entity){ $,)PO
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return getHibernateTemplate().find("from NrK.DY4
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" + entity.getName()); ls*bCe
} 45aUz@
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publicList findByNamedQuery(finalString e>] gCa
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namedQuery){ Z.l4<
return getHibernateTemplate S<Os\/*
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().findByNamedQuery(namedQuery); x,% %^(
} a7@':Rb n
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publicList findByNamedQuery(finalString query, ("r\3Mvs
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finalObject parameter){ :2zga=)g
return getHibernateTemplate BH"OphE
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().findByNamedQuery(query, parameter); y9)w(y!
} pv[Gg^
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publicList findByNamedQuery(finalString query, je`Ysbe n
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finalObject[] parameters){ >_J9D?3S
return getHibernateTemplate SIridZ*%
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().findByNamedQuery(query, parameters); !*eDT4a
} Oo0SDWI`(
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publicList find(finalString query){ 0Fw4}f.o
return getHibernateTemplate().find T@%\?=P
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(query); bt{b%r
} Ls`[7w
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publicList find(finalString query, finalObject 'CMbqLk#
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parameter){ 2<FEn$n[
return getHibernateTemplate().find 2z9s$tp
{ MV,>T_
(query, parameter); ?Qxf~,F
} FMi:2.E
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public PaginationSupport findPageByCriteria 2Onp{,'}
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(final DetachedCriteria detachedCriteria){ f
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return findPageByCriteria IE|? &O
@ tvz9N
(detachedCriteria, PaginationSupport.PAGESIZE, 0); g&*,j+$ }
} XkPE%m_5D
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public PaginationSupport findPageByCriteria 7tbY>U8
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(final DetachedCriteria detachedCriteria, finalint uc>":V
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startIndex){ ZXIw^!8@/
return findPageByCriteria _70Z1_;
@V&c=8)8
(detachedCriteria, PaginationSupport.PAGESIZE, FS)"MDs
*
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startIndex); ;,}Dh/&E
} Z%Fc
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public PaginationSupport findPageByCriteria 3_ly"\I\
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(final DetachedCriteria detachedCriteria, finalint ;_=N
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pageSize, `/O AgV"`
finalint startIndex){ Kh$Q9$
return(PaginationSupport) E<l/o5<nC
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getHibernateTemplate().execute(new HibernateCallback(){ lrAhdi
publicObject doInHibernate -VeCX]
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(Session session)throws HibernateException { b'W.l1]<-
Criteria criteria = byFO^pce
l*?_ @
detachedCriteria.getExecutableCriteria(session); Z]e`bfNnI
int totalCount = lSg[7lt
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((Integer) criteria.setProjection(Projections.rowCount -.Blj<2ah
h
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()).uniqueResult()).intValue(); {h=gnR-9
criteria.setProjection 84WX I#BH
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(null); T]JmnCX>:
List items = \h"U+Bv7
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criteria.setFirstResult(startIndex).setMaxResults _u+ 7>
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(pageSize).list(); Pa6pq;4St
PaginationSupport ps = [#9i@40
* bd3^mP
new PaginationSupport(items, totalCount, pageSize, $J^fp XO
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startIndex); RG*Vdom
return ps; $AT@r"
} ^)wKS]BQ..
}, true); zak|* _
} a'-u(Bw
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public List findAllByCriteria(final ae2Q^yLA
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DetachedCriteria detachedCriteria){ d[>HxPwo
return(List) getHibernateTemplate [~u!*W
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().execute(new HibernateCallback(){ lLp,sNAj
publicObject doInHibernate :r@t '
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(Session session)throws HibernateException { ^?$,sS
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Criteria criteria = _1NK9dp:
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detachedCriteria.getExecutableCriteria(session);
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return criteria.list(); Q6W![571;
} i!zFW-*5
}, true); xorafL
} %@Z;;5 L
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public int getCountByCriteria(final #1/~eIEY
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DetachedCriteria detachedCriteria){ {vGJ}q?Sd"
Integer count = (Integer) zGFD71=#
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getHibernateTemplate().execute(new HibernateCallback(){ MoE&)~0u&
publicObject doInHibernate (c>g7d<>n
l2LLM {B
(Session session)throws HibernateException { UrHndnqM
Criteria criteria = +ID\u
<?
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detachedCriteria.getExecutableCriteria(session); puJB&u"4L
return >v %js!`f
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criteria.setProjection(Projections.rowCount
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()).uniqueResult(); J Cq>;br.
} _0jR({\
}, true); {G Jl<G1
return count.intValue(); m/1FVC@*
} b?l>vUgAg
} GPGE7X'
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用户在web层构造查询条件detachedCriteria,和可选的 !+Xul_XG
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Oj;*Gi9E
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PaginationSupport的实例ps。 FDQ=$w}'>
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ps.getItems()得到已分页好的结果集 MzD1sWmK
ps.getIndexes()得到分页索引的数组 a(|6)w-
ps.getTotalCount()得到总结果数 %(1OjfZc
ps.getStartIndex()当前分页索引 RbX9PF"|+
ps.getNextIndex()下一页索引 )"S%'myj
ps.getPreviousIndex()上一页索引 I@MG?ZQ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 kU[hB1D5
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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 l!f_ +lv
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一下代码重构了。
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我把原本我的做法也提供出来供大家讨论吧: J5G<Y*q
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首先,为了实现分页查询,我封装了一个Page类:
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java代码: pM?~AYWb
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/*Created on 2005-4-14*/ E{<#h9=>
package org.flyware.util.page; t,?,T~#9
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/** (dq_,LI
* @author Joa =/Gd<qz3
* . vb##D
*/ -N*[f9EJB
publicclass Page { $6a9<&LP_
zr/v .$<
/** imply if the page has previous page */ Y"H`+UV
privateboolean hasPrePage; 1zPS#K/3
8>9Mh!t}(I
/** imply if the page has next page */ Z)s
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privateboolean hasNextPage; "[N2qJ}p
+})QT FV
/** the number of every page */ ?4bYb]8Z
privateint everyPage; MY,~leP&
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/** the total page number */ 1.du#w
privateint totalPage; dd
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/** the number of current page */ x95s%29RS
privateint currentPage; t`Kpbfk
LDr?'M!D
/** the begin index of the records by the current e*2^
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query */ AioW*`[WjA
privateint beginIndex; ij$NTY=u
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/** The default constructor */ g8Ex$,\,
public Page(){ .;4N:*hY
,{PN6B
} -TF},V~
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/** construct the page by everyPage yMN JHiE/
* @param everyPage TRi'l #m4
* */ ,Vi_~b
public Page(int everyPage){ 9<u&27.
this.everyPage = everyPage; h-96 2(LG
} >%tP"x{
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/** The whole constructor */ $5i\D
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public Page(boolean hasPrePage, boolean hasNextPage, ~^2w)-N
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int everyPage, int totalPage, Ak?9a_f
int currentPage, int beginIndex){ M2Nh3ijr
this.hasPrePage = hasPrePage; f SkC>mWv
this.hasNextPage = hasNextPage; PEI$1,z
this.everyPage = everyPage; {N2GRF~c-y
this.totalPage = totalPage; @@D/&}#F
this.currentPage = currentPage; 9
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this.beginIndex = beginIndex; j\>&]0-Iq
} z:-{Y2F
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/** u&l;\w
* @return `,V&@}&"n
* Returns the beginIndex. 6>WkisxG
*/ jWUrw
publicint getBeginIndex(){ 9K&$8aD
return beginIndex; ^UvL1+
} 0XA\Ag\`G
!f/K:CK|
/**
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* @param beginIndex eQ'E`S_d
* The beginIndex to set. Yb5U^OjyJ
*/ 1'hpg>U
publicvoid setBeginIndex(int beginIndex){ f/sz/KC]~
this.beginIndex = beginIndex; 2!6hB sEr
} (f&V 7n
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/** ;-1KPDIp`
* @return Vx!ZF+
* Returns the currentPage. I%4eX0QY=z
*/ (Iv@SiZf(
publicint getCurrentPage(){ ~aotV1"D
return currentPage; #X)DFAtb
} 9BakxmAc
&3iI\s[
/** W>' DQB
* @param currentPage XIMh<
* The currentPage to set. 570ja7C:
*/ 1Lf -
publicvoid setCurrentPage(int currentPage){ iX?j "=!
this.currentPage = currentPage; .Yk}iHcW.
} 4M"'B A<
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/** |}77'w :
* @return glch06
* Returns the everyPage. bD
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*/ I]HYqI
publicint getEveryPage(){ Oyb9
ql^
return everyPage; NkUY_rKPb
} _oZ3n2v}@
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/** r`ftflNh(
* @param everyPage n'ZPB
* The everyPage to set. &DQ_qOKD
*/ [p4([ef
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publicvoid setEveryPage(int everyPage){ #IppjaPl8
this.everyPage = everyPage; VN-0hw/A
} .\`MoH
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/** BHpay
* @return &4wSX{c/P
* Returns the hasNextPage. +sx(q@
*/ &(<Gr0
publicboolean getHasNextPage(){ E7$ aT^
return hasNextPage; LI-ewea
} tG]W!\C'h
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/** un\o&0}
* @param hasNextPage l )r^|9{
* The hasNextPage to set. yu#m6K
*/ N8T.Ye N
publicvoid setHasNextPage(boolean hasNextPage){ s|WcJV
this.hasNextPage = hasNextPage; QfjoHeG7
} ]@_|A, ]
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/** Z{u]qI{l
* @return `m V(:
* Returns the hasPrePage. rxxVLW
*/ Eb,M+c?
publicboolean getHasPrePage(){ oVl:g:K40
return hasPrePage; b 2\J<Nw
} eLH=PDdO
A
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/** `MT.<5H
* @param hasPrePage P{RGW.Ci@
* The hasPrePage to set. ,H|K3nh
*/ pw))9~XU
publicvoid setHasPrePage(boolean hasPrePage){ u$qasII
this.hasPrePage = hasPrePage; VaonG]Ues
} ;Zf7|i`R3
7iy 2V;}
/** Us[F@
* @return Returns the totalPage. _or_Vw!
* g6gwNC:aF
*/ KfK5e{yT
publicint getTotalPage(){ 0{!-h
return totalPage; /`qQWB5b
} }V/iU_)
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/** 6d5q<C_3t
* @param totalPage iOAn/[^xk
* The totalPage to set. 3? k<e
*/ zl, Vj%d
publicvoid setTotalPage(int totalPage){ vqF=kB"P
this.totalPage = totalPage; 6XAofN/5f
} !;t6\Z8&
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} <UIE-#
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 N5MWMN[6aP
29z@ !
个PageUtil,负责对Page对象进行构造: XB[EJGaX
java代码: B$q5/ L$}
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/*Created on 2005-4-14*/ nh+h3"-d
package org.flyware.util.page; Ix@nRc'
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import org.apache.commons.logging.Log; jlyuu
import org.apache.commons.logging.LogFactory; 16ip:/5
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/** l:a#B
* @author Joa !h^_2IX
* g/!tp;e
*/ *I9O63
publicclass PageUtil { nWd;XR6|
NwKj@ Jos
privatestaticfinal Log logger = LogFactory.getLog f(EO|d^u
1#zD7b~
(PageUtil.class); i\>?b)a>
^= kr`5
/** %4wHiCOg
* Use the origin page to create a new page Nah\4-75&
* @param page 8yswi[
* @param totalRecords hBDmC_\~
* @return !%D;H ~mQ
*/ $m-@ICG#
publicstatic Page createPage(Page page, int 6,l5Q
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totalRecords){ Rx@0EPV
return createPage(page.getEveryPage(), FZ FPzH
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page.getCurrentPage(), totalRecords); *y~~~ 'J/
} e\ZV^h}TQ
gP!k[E,Q8
/** Gfepm$*%
* the basic page utils not including exception "`KT7
VTO92Eo
handler nwi8>MG
* @param everyPage \h}sA
* @param currentPage E]pDp
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* @param totalRecords MMQ\V(C
* @return page 0Y!~xyg/
*/ I#(?xHx
publicstatic Page createPage(int everyPage, int K:$GmV9o
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currentPage, int totalRecords){ A*kN
I
everyPage = getEveryPage(everyPage); *"V) hI5
currentPage = getCurrentPage(currentPage); N.V5>2
int beginIndex = getBeginIndex(everyPage, $%1oZ{&M
T'5MO\
currentPage); +^$E)Ol
int totalPage = getTotalPage(everyPage, S<I9`k G
[1e/@eC5
totalRecords); 'qoaMJxN`
boolean hasNextPage = hasNextPage(currentPage, <I{Yyl^
u} [.*e
totalPage); cmp@Ow"c
boolean hasPrePage = hasPrePage(currentPage); ,C^u8Z|T
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returnnew Page(hasPrePage, hasNextPage, /vLW{ %
everyPage, totalPage, DH])Q5
currentPage, .aC/ g?U
NC"X{$o2
beginIndex); ,H]S-uK~
} ;(Z9.
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privatestaticint getEveryPage(int everyPage){ AZ.
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return everyPage == 0 ? 10 : everyPage; DLoH.Fd
} FY,)iZ}Pq
6^ ,;^
privatestaticint getCurrentPage(int currentPage){ FD8d-G
return currentPage == 0 ? 1 : currentPage; "i\^GK=
} :>3?|Z"Aj
ZkF6AF
privatestaticint getBeginIndex(int everyPage, int ?V =#x.9
we33GMxHl`
currentPage){ u"U7aYGkY
return(currentPage - 1) * everyPage; cE*d(g
} 5C5OLAl v
!wo
privatestaticint getTotalPage(int everyPage, int G9~ 4?v6:
C|S~>4`
totalRecords){ N LSJ
D
int totalPage = 0; x.q "FXu
&iaS3x
if(totalRecords % everyPage == 0) Pu,2a+0N
totalPage = totalRecords / everyPage; 3
t+1M
else V?n=yg
totalPage = totalRecords / everyPage + 1 ; To,*H OP
whQJWi=ck
return totalPage; CS;4 ysNf
} 5M#LO@U
n}8}:3"
privatestaticboolean hasPrePage(int currentPage){ $OaxetPH
return currentPage == 1 ? false : true; +-Z `v
} Bh65qHQO
E_#?;l>
privatestaticboolean hasNextPage(int currentPage, rs0Wy
lB
int totalPage){ RVh{wg
return currentPage == totalPage || totalPage == a-NicjV#
V=H :`n3k
0 ? false : true; Bm+Ca:p%
} ,Y7QmbX^
5jsZJpk$
wB"`lY
} C/q!!
3 ]pHc)p!.
se29IhS!e
_W>xFBy
HnKXO
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。 QVkrhwp
e. R9:
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 ggy9euWV
CsN^u H
做法如下: cT
nC
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 f8)fm2^09
BR:Mcc
的信息,和一个结果集List: eaDG7+iS
java代码: D=}\]Krmay
#j)"#1IE2W
BCh|^Pk
/*Created on 2005-6-13*/ ">vi=Tr
package com.adt.bo; wQ81wfr1:
=G`g-E2
import java.util.List; L.: 8qY
ipS:)4QFxJ
import org.flyware.util.page.Page; -[[(Zx
zxeT{AFPr?
/** -0P9|;h5
* @author Joa 5 &0qr$
*/ .Gb!mG
publicclass Result { sEi9<$~R@0
ZKai*q4?
private Page page; sGc.;":
I5ZM U
private List content; U+&Eps&NI
a`>H69(bU
/** }ldpudU
* The default constructor KCnm_4
*/ 6i@* L\
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public Result(){ -s]@8VJA"
super(); M[(pLYq:
} $CZ'[`+
w[AL'1s]
/** ]88qjKL
* The constructor using fields $dG:29w
* U_WO<uhC
* @param page IRTD(7"oyp
* @param content wZWAx
*/ ;RYIc0%
public Result(Page page, List content){ DKF
'*
this.page = page; 5<YL^m{/L
this.content = content; &d\ y:7
} *q+X?3
"<LWz&e^^
/** Zpz3?VM(
* @return Returns the content. ilAhw4A
*/ d0;?GQYn:
publicList getContent(){ V)P8w#,
return content; >T-4!ZvS\j
} =nqHVRA
dg_w$#
/** 'c# }^@G
* @return Returns the page. U>DCra;
*/ uF<?y0t
public Page getPage(){ ~0@fK<C)O
return page; AWJA?
} QQv%>=_`
<T&v\DN
/** tS-gaT`T
* @param content 73Hm:"Eqd
* The content to set. Fu5c_"!
*/ ,e$6%R
public void setContent(List content){ F~eY'~&H}
this.content = content; -+0kay%
} $m A2AI
RGrQ>'RL
/** <>728;/C
* @param page 6&il>
* The page to set. @_1cY#!
*/ m.<u!MI
publicvoid setPage(Page page){ Qxk & J
this.page = page; o4wSt6gBcJ
} gtePo[ZH.P
} B9Hib1<8
hCS}
3#Bb4\_v
-:E~Z_J`
3R0ioi 7
2. 编写业务逻辑接口,并实现它(UserManager, $sS~hy*
2=/-,kOL_
UserManagerImpl) zTc*1(^
java代码: Qj*.Z4ue
Q<gUu^rq
jFUpf.v2
/*Created on 2005-7-15*/ MpBdke$
package com.adt.service; FRQ0t!b<M1
K6sXw[VC[
import net.sf.hibernate.HibernateException; w)`XM
@\o"zU
import org.flyware.util.page.Page; I2Imb9k~B
iaLZ|\`3a
import com.adt.bo.Result; PjH'5Y
Wky9wr:g
/** -$DfnAh
* @author Joa v; R2,`[W
*/ xiDgQTDz
publicinterface UserManager { 8;r #HtFM
*0to,$ n
public Result listUser(Page page)throws i;-M8Q^
v?Utz~lQ
HibernateException; gu+zfvkcY
6su~SPh
} o]RZd--c<
b $JS|
@Z2np{X:
O1S7t)ag
CH&{x7$he
java代码: ml<tH2Qx3C
.Z
67
y^ |u'XK
/*Created on 2005-7-15*/ ],k~t5+
package com.adt.service.impl; 7eAV2.
se`Eez}
import java.util.List; ~> Q9
,G g;:)k\
import net.sf.hibernate.HibernateException; 9)NKI02M|
oLh ,F"nB
import org.flyware.util.page.Page; 8-B7_GoJ+B
import org.flyware.util.page.PageUtil; ;o9ixmT<-o
\~"Ub"~I
import com.adt.bo.Result; }\Rmwm-
import com.adt.dao.UserDAO; &9fQW?Czs
import com.adt.exception.ObjectNotFoundException; ?_i>Kx
import com.adt.service.UserManager; V~ORb1
BdF/(Pg
/** yCvtglAJ4
* @author Joa
S#?2E8
*/ XUA@f*
publicclass UserManagerImpl implements UserManager { -1RMyVx
r9Ogez ER
private UserDAO userDAO; J E7m5kTa
f?51sr
/** dGn0-l'q
* @param userDAO The userDAO to set. eqsmv[
*/ j~G(7t
publicvoid setUserDAO(UserDAO userDAO){ rpK&OR/
this.userDAO = userDAO; )N8bOI
} h]s~w
eNK[P=-
/* (non-Javadoc) oV0T
* @see com.adt.service.UserManager#listUser 9K/EteS
2Y23!hw
(org.flyware.util.page.Page) |w}j!}u
*/ dN)8r
public Result listUser(Page page)throws T7.Iqw3p
@$ Zh^+x!
HibernateException, ObjectNotFoundException { Z17b=xJw
int totalRecords = userDAO.getUserCount(); BZ1wE1 t
if(totalRecords == 0) 5P%#5Yr2
throw new ObjectNotFoundException d#a/J.Z$A
~x\uZ^:
("userNotExist"); >&KH!:OX|
page = PageUtil.createPage(page, totalRecords); 9<.O=-1~
List users = userDAO.getUserByPage(page); [
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returnnew Result(page, users); e;"J,7@
} E|"SMA,
KE~Q88s
} YHQ]]#'
3HpqMz
M7cD!s@'I
8qg%>ZU4d
C$TU
TS
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 ou <3}g
XGR2L
DR
询,接下来编写UserDAO的代码: s@ @Km1w
3. UserDAO 和 UserDAOImpl:
pE)NSZ
java代码: Ee2P]4_d
"u!gfG?oH
dX cbS<
/*Created on 2005-7-15*/ QQ .?A(U7
package com.adt.dao; \ +%~7Bi]z
~p?ArZb
import java.util.List; XNWtX-[^@
t.28IHJ
import org.flyware.util.page.Page; |p&EP2?T
BZ?3=S1*
import net.sf.hibernate.HibernateException; CF{b Yf^%
&/]en|f"
/** vS>'LX
* @author Joa >X$JeME3
*/ 'NhQBk
publicinterface UserDAO extends BaseDAO { ly17FLJ].
k8+J7(_c
publicList getUserByName(String name)throws hhy+bA}
id1cZig
HibernateException; |VWT4*K
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publicint getUserCount()throws HibernateException; s Z[[ymu8
0vm> *M*p
publicList getUserByPage(Page page)throws hLLSmW(
djOjd,
HibernateException; 3y}E*QE
d^aVP
} P[
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OB(oOPH
x950,`zy
1RYrUg"s"
8~C_ng-wn
java代码: VO|ECB2e
UPuoIfuqI
"#r)NYq`"|
/*Created on 2005-7-15*/ u;_h%z5K
package com.adt.dao.impl; S\).0goOW
1y'Y+1.<
import java.util.List; e
Wux
^~YT<cJ1h
import org.flyware.util.page.Page; 'ztOl`I5V
lI=<lmM0|/
import net.sf.hibernate.HibernateException; (SBhU:^h
import net.sf.hibernate.Query; 90<g=B
{-\U)&6#v
import com.adt.dao.UserDAO; k."p&
\~
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/** d&j
* @author Joa ukSv70Ev
*/ Jp=fLo 9
public class UserDAOImpl extends BaseDAOHibernateImpl xQu|D>kv87
JI5o~;}m
implements UserDAO { t@qf/1
9=>fx
/* (non-Javadoc) QhZg{v[d
* @see com.adt.dao.UserDAO#getUserByName vV}w>Ap[
k8w\d+!v
(java.lang.String) 8z#Qp(he
*/ F^u12R)
publicList getUserByName(String name)throws >NKJ@4Y
xs{pGQ6Q
HibernateException { f jx`|MJ
String querySentence = "FROM user in class nqyD>>
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gCOr
com.adt.po.User WHERE user.name=:name"; j,k3]bP
Query query = getSession().createQuery h !^=
c
*S.U8;*Xj
(querySentence); 5?7AzJl>
query.setParameter("name", name); @j/2 $
return query.list(); &?@C^0&QV
} Y %"Ji[
j7~FR{:j
/* (non-Javadoc) *jlIV$r_
* @see com.adt.dao.UserDAO#getUserCount() UHZuH?|@
*/ {~U3|_"[pX
publicint getUserCount()throws HibernateException { yH/A9L,Z
int count = 0; .e~"+Pe6b
String querySentence = "SELECT count(*) FROM }UhYwJf89
&xnQLz:#
user in class com.adt.po.User"; vF27+/2+R
Query query = getSession().createQuery XnyN*}8
QKG3>lU
(querySentence); 3Qy@^"
count = ((Integer)query.iterate().next q)k:pQ
KNVu[P)rv
()).intValue(); %_OjmXOfe
return count; ^#Ii=K-[^
} <u64)8'
N''QQBUD
/* (non-Javadoc) yKc-:IBb{u
* @see com.adt.dao.UserDAO#getUserByPage u R0UfKK
b[74$W{
(org.flyware.util.page.Page) T`&zQQ6F'
*/ rW{!8FhI
publicList getUserByPage(Page page)throws 0pZvW
]@{Lx>Oh"
HibernateException { my?Ly(#
String querySentence = "FROM user in class IVR%H_uz
23}` e
com.adt.po.User"; jf9+H!?^N
Query query = getSession().createQuery y{ur'**l
!jj`Ht)
(querySentence); P%3pM*.
query.setFirstResult(page.getBeginIndex()) 8z9{H
.setMaxResults(page.getEveryPage()); #{cy( &cz
return query.list(); @aIgif+v
} @5>#<LV=E#
NAR6q{c
} :viW
`b?uQ\#-M
J&xZN8jW
.GrOdDK$ns
l=~!'1@L}
至此,一个完整的分页程序完成。前台的只需要调用 YF5}~M ymF
MEDh
userManager.listUser(page)即可得到一个Page对象和结果集对象 /F0q8j0
^ ""edCs
的综合体,而传入的参数page对象则可以由前台传入,如果用 I|@+O#
/DQYlNa
webwork,甚至可以直接在配置文件中指定。 gEh/m.L7
H1bR+2s
下面给出一个webwork调用示例: I3t5S;_8
java代码: #D`@G8~(
XM$~HG
>US*7m }
/*Created on 2005-6-17*/ $L/`nd
package com.adt.action.user; :{7+[LcH7
Xg)8}
import java.util.List; KkJqqO"EL
{9x_E {
import org.apache.commons.logging.Log; <Ky-3:pxeM
import org.apache.commons.logging.LogFactory; WZ CI*'
import org.flyware.util.page.Page; Z
vysLHj
&\h7E
import com.adt.bo.Result; 1!#N-^qk
import com.adt.service.UserService; `Q@7,z=f
import com.opensymphony.xwork.Action; M(-)\~9T
Ca2r<|uA
/** LPvp
(1
* @author Joa EZUaYp~M
*/ fQ<sq0'e\
publicclass ListUser implementsAction{ F? #3
DHO]RRGV
privatestaticfinal Log logger = LogFactory.getLog Blpk
n1
yJA~4
(ListUser.class); +}:Z9AAMy
:/5m
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private UserService userService; }`tSRB7
;+Jx,{)
private Page page; 0Hnj<| HL
8D*7{Q
privateList users; &o:5lxR{
[M|^e;tWK
/* =*\s`ox`
* (non-Javadoc) ;blL\|ch;
* ?@64gdlwq
* @see com.opensymphony.xwork.Action#execute() =2R4Z8G
*/ ":]Xr!e
publicString execute()throwsException{ g3^s_*A
Result result = userService.listUser(page); 6!<I'M'[e
page = result.getPage(); "Y&I#&$b\
users = result.getContent(); [&lK.?V)
return SUCCESS; il0K ^i
} O. * 0;5
(v]%kXy/G
/** z:QDWH
* @return Returns the page. bZu'5+(@
*/ R"nB4R0Uh
public Page getPage(){ g4?2'G5m?
return page; Oa[
} %|-N{> wKy
AWO)]rM
/** bWe2z~dP
* @return Returns the users. w\buQ6pR)
*/ ;n&95t1$
publicList getUsers(){ T.bFB+'E|
return users; :5YIoC
} ]N>ZOV,>
#:)'D?,
/** DE(XSzX
* @param page ]*0zir/
* The page to set. [|nK5(e9
*/ vhe Y
F@
publicvoid setPage(Page page){ TvU
z^
this.page = page; +=tdgw/
} 1XGg0SC
)GB#"2
/** nrEI0E9
* @param users :.:^\Q0
* The users to set. U:7h>Z0W
*/ +){^HC\7h
publicvoid setUsers(List users){ l+ }=D@l
this.users = users; 4n,&,R r#
} G]lGoa}]`u
&PMQ]B
/**
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* @param userService :jiEn
y
* The userService to set. Fis!MMh.$
*/ ~
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publicvoid setUserService(UserService userService){ dSDZMB sd
this.userService = userService; u8f\)m
} \0\ O/^W0
} O& Y;/$w
%ZVYgtk;*
WjVBz
JVAyiNIH>M
+Mj6.X
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, ; lMv xt:
0R?1|YnB
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 (UkP AE
pqG>|#RG
么只需要: x@#>l8k?
java代码: ?2@^O=I
|rx5O5p
;*%rFt9FK
<?xml version="1.0"?> **q8vhJM
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork @?B+|*cm
h,LSqjf"
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 5U84*RY
U,rI/'
1.0.dtd"> H,>
}t
S
d)
-(C1f
<xwork> jcCAXk055
b4L7M1l
<package name="user" extends="webwork- 54$^ldD
"P !
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interceptors"> ,%pCcM)
[@i:qB>B
<!-- The default interceptor stack name >.<VD7p
6[m~xegG
--> #Xg;E3BM
<default-interceptor-ref ^ :VH?I=
CHnclT
name="myDefaultWebStack"/> K V5
'-Sv1
W8W7<ml0A
<action name="listUser"
>a"J);p
Vgm*5a6t
class="com.adt.action.user.ListUser"> XIcUoKg^
<param ^".OMS"!
m?S;sew@5
name="page.everyPage">10</param> E%w^q9C
<result BJ
UG<k
:zL)O
name="success">/user/user_list.jsp</result> [ycX)iM
</action> 9p_?t'&>q
s&73g0$$
</package> BlJiHz!
p4T$(]7
</xwork> b0~r/M;J
n/9afIN
V%-hP~nyBx
V60L\?a
Q[OwP
.`D'eS6b
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 ItVN,sVJb
93*csO?Db
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 p%I)&- 8
N[Z`tk?-
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 &d6@SQ
eo+<@83
f-~Y
~[CFs'`(2
;L-=z]IR,
我写的一个用于分页的类,用了泛型了,hoho Sz5t~U=G
P@N+jS`Vf
java代码: /
9=j9vBV
` GF w?G
package com.intokr.util; :FAPH8]
\HGf!zZ
import java.util.List; 3 =enk0$
sq$v6x sl
/** DI\=udN
* 用于分页的类<br> 5dj" UxH
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ]\*^G@HA2
* 3d}v?q78
* @version 0.01 NQ{(G8x9
* @author cheng F`g(vD>
*/ H07\z1?.K
public class Paginator<E> { #eW
T-m
privateint count = 0; // 总记录数 `n&:\Ib
privateint p = 1; // 页编号 *OLqr/ yb
privateint num = 20; // 每页的记录数 1Q@]b_"Xh
privateList<E> results = null; // 结果 .UPh
`7/(sX.
/** /1OCK=
* 结果总数 c~<;}ve^z
*/ J&8KIOz14Z
publicint getCount(){ +a5F:3$
return count; O`Tz^Q/D
} ]}3s/NJi
\_Bj"K
publicvoid setCount(int count){ P j
this.count = count; ]BO:*&O
} R U)(|;
wn"}<ka
/** "B QnP9
* 本结果所在的页码,从1开始 Z- feMM
* C8m 9H8Qm
* @return Returns the pageNo. b,'O|s]"Sc
*/ 01A{\O1$j
publicint getP(){ 6H |1IrG
return p; >jt2vU@t.
} [
U:C62oK,
JL6$7h
/** 4>,X.|9{
* if(p<=0) p=1 nH#>_R
(
* C hF~
* @param p Y-ao
yoNS
*/ UGAV"0
publicvoid setP(int p){ <YyE1|
if(p <= 0) (%6fMVp
p = 1; |nNcV~%~
this.p = p; Sf?;j{?G
} Vuz.b.,i`
R*r4)+gd
/** UF+Qx/4h0
* 每页记录数量 2>o[
*/ ZDW9H6ux
publicint getNum(){ i<Z%
return num; B|m)V9A%-
} &J3QO%
3RaduN]
/** AR[m+E
* if(num<1) num=1 u`'"=Y_E
*/ D, ")n75
publicvoid setNum(int num){ 9,?~dx
if(num < 1) WE\TUENac(
num = 1; I[?\Or
this.num = num; nXT`7
} yXU.PSG*
gkr9+
/** p#$/{;yy
* 获得总页数 4Fg2/O_3
*/ AYn65Ly
publicint getPageNum(){ Fx^wV^q3
return(count - 1) / num + 1; YPGM||
} ji ?Hw
:;_
khno
/** :9hGL
* 获得本页的开始编号,为 (p-1)*num+1 (4FVemgy
*/ PK+sGV
publicint getStart(){ ${T/b(NM
return(p - 1) * num + 1; @;egnXxF<