Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 H& |/|\8F
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 >|f"EK}m!
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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 wgl <JO
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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 (bwD:G9
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分页支持类: O(^h_
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java代码: t. P@Ba^
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package com.javaeye.common.util; +O}Ik.w
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import java.util.List; n!)$e;l
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publicclass PaginationSupport { 0jTReY-W
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publicfinalstaticint PAGESIZE = 30; q/O2E<=w*c
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privateint pageSize = PAGESIZE; :_e[xB=Yy
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privateList items; _ *f>UW*,
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privateint totalCount; =AIts[!qd
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privateint[] indexes = newint[0]; dq93P%X24
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privateint startIndex = 0; adLL7
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public PaginationSupport(List items, int nCQtn%j't
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totalCount){ hGtz[u#p
setPageSize(PAGESIZE); PR8nJts W5
setTotalCount(totalCount); Xf
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setItems(items); Q-7?'\h
setStartIndex(0); }c/p;<
} wGyVmC
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public PaginationSupport(List items, int 3FBL CD3
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totalCount, int startIndex){ ucN'
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setPageSize(PAGESIZE); '=dQ$fs
setTotalCount(totalCount); h;V4|jM
setItems(items); $|K:
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setStartIndex(startIndex); ,Lig6Z`
} |ADf~-AY
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public PaginationSupport(List items, int ^r~[3NT
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totalCount, int pageSize, int startIndex){ ^{M$S0g|N
setPageSize(pageSize); 4=Th<,<
setTotalCount(totalCount); t;* zr*
setItems(items); =B}IsBn'J
setStartIndex(startIndex); ng}C$d . I
} K_YrdA)6
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publicList getItems(){ ciS +.%7
return items; $nt&'Xnv
} {irc0gI
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publicvoid setItems(List items){ <h -)zI
this.items = items; ZJDV'mC}
} q`xc h[H
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publicint getPageSize(){ ^4`aONydl
return pageSize; 0qS/>u*
} Wga2).j6
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publicvoid setPageSize(int pageSize){ _dKMBcl)E
this.pageSize = pageSize; 8T1`9ITl:
} &%2^B[{
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publicint getTotalCount(){ od=hCQ1>
return totalCount; VrIN.x
} <^YvgQ,m
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publicvoid setTotalCount(int totalCount){ 1jKpLTSs
if(totalCount > 0){ m.D8@[y
this.totalCount = totalCount; aE~T!h
int count = totalCount / N<Sl88+U
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pageSize; m.lR]!Y=w
if(totalCount % pageSize > 0) oJa}NH
count++; #Z1%XCt
indexes = newint[count]; z|pt)Xl
for(int i = 0; i < count; i++){ z/\OtYz
indexes = pageSize * Mt.Cj;h@^[
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i; }m+Q(2
} cZVx4y%kz
}else{ O#D{:H_dD>
this.totalCount = 0; aM~IRLmK
} cKTjQJ#
} Ta\F~$M
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publicint[] getIndexes(){ Sr
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return indexes; ;"M6}5dQ4
} ~vXbh(MX
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publicvoid setIndexes(int[] indexes){ >6S7#)0T
this.indexes = indexes; k]p|kutQCy
} Jl_W6gY"Z
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publicint getStartIndex(){ g+B7~Z5,
return startIndex; ]N 9N][n
} [H*JFKpx
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publicvoid setStartIndex(int startIndex){ .jJD$FC
if(totalCount <= 0) .57p4{
this.startIndex = 0; )K[\j?
elseif(startIndex >= totalCount) [xiqlb,8
this.startIndex = indexes ,#2~<
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[indexes.length - 1]; G2|jS@L#
elseif(startIndex < 0) r;{$x
this.startIndex = 0; rt^~
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else{ BL&AZv/T
this.startIndex = indexes SZH`-xb!+5
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[startIndex / pageSize];
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}
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} 7"!`<5o^
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publicint getNextIndex(){ #G#gc`S-,
int nextIndex = getStartIndex() + =\lw.59
# Wi?I=,
pageSize; ~61b^L}$
if(nextIndex >= totalCount) d.?}>jl
return getStartIndex(); #@oB2%&X?
else VpJKH\)Rt(
return nextIndex; y'm!h?8
} p6%V f
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publicint getPreviousIndex(){ Z"VP<-
int previousIndex = getStartIndex() - U~D~C~\2;
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pageSize; h/ n(
if(previousIndex < 0) fG1iq<~
return0; #
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else X\`']\l
return previousIndex; L2>e@p\>
} |Y
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} %T]$kF++&
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抽象业务类 ]A2E2~~G
java代码: >
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/** Oa/zEH
* Created on 2005-7-12 VgVDTWs7
*/ Qa,=
package com.javaeye.common.business; G%sq;XT61
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import java.io.Serializable; 'S3<' X
import java.util.List; wF`Y
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import org.hibernate.Criteria; Jw _>I
import org.hibernate.HibernateException; 'Ou C[$Z
import org.hibernate.Session; .=;IdLO,Bf
import org.hibernate.criterion.DetachedCriteria; %>$<s<y
import org.hibernate.criterion.Projections; bB?E(>N;
import g4A{RI
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org.springframework.orm.hibernate3.HibernateCallback; @ZU$W9g
import 9:p-F+
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org.springframework.orm.hibernate3.support.HibernateDaoS l~"T>=jq3
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upport; jh/,G5RM9
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import com.javaeye.common.util.PaginationSupport; %rb$tKk
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public abstract class AbstractManager extends 8;?4rrS
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HibernateDaoSupport { &B&8$X
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privateboolean cacheQueries = false; r>(,)rs(l
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privateString queryCacheRegion; 0{b} 1D
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publicvoid setCacheQueries(boolean -8^qtB
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cacheQueries){ SO6)FiPy!n
this.cacheQueries = cacheQueries; ASHU0v
} '?Dxe
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publicvoid setQueryCacheRegion(String CFh9@Nx
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queryCacheRegion){ #VrIU8Q7'
this.queryCacheRegion =
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queryCacheRegion; /:F^*]
} M/6Z,oOU
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publicvoid save(finalObject entity){ ~uc7R/3ss
getHibernateTemplate().save(entity); qA GjR!=^
} ]P3m=/w
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publicvoid persist(finalObject entity){ MoFM'a9
getHibernateTemplate().save(entity); $ztsb V}
} v\,N"X(,
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publicvoid update(finalObject entity){ bqED5;d'#
getHibernateTemplate().update(entity); nx'c=gp
} O=3/qs6m
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publicvoid delete(finalObject entity){ JVuju$k
getHibernateTemplate().delete(entity); ,*iA38d.!
} bqE'9GI
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publicObject load(finalClass entity, nq{/fD(2
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finalSerializable id){ ^+76^*0
return getHibernateTemplate().load e>z"{ u(F0
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(entity, id); l?*DGW(t{
} Zkd{EMW
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publicObject get(finalClass entity, AI2XNSV@Yl
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finalSerializable id){ Iuxf`sd
return getHibernateTemplate().get uHI(-!O
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(entity, id); ]B3](TH"
} #r9+thyC
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publicList findAll(finalClass entity){ -iiX!@
return getHibernateTemplate().find("from _uO$=4Sd
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" + entity.getName()); AU\=n,K7
} *Y(59J2
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publicList findByNamedQuery(finalString ^^V3nT2rR3
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namedQuery){ =R=V
return getHibernateTemplate C*2%Ix18+N
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().findByNamedQuery(namedQuery); !Axe}RD'
} !}!KT(%%
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publicList findByNamedQuery(finalString query, (C.
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finalObject parameter){ m ~&
return getHibernateTemplate <'4Wne.z!
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().findByNamedQuery(query, parameter); `Xos]L'w
} dq '2y
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publicList findByNamedQuery(finalString query, WPRk>j
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finalObject[] parameters){ 3 ZOD2:(
return getHibernateTemplate A1p~K*[[
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().findByNamedQuery(query, parameters); f![] :L
} dT0W8oL
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publicList find(finalString query){ 4<($ZN8
return getHibernateTemplate().find ` &A`&-nc=
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(query); 1x_EAHZ>7
} :=hL}(~]
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publicList find(finalString query, finalObject iTinZ!Ut
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parameter){ j9k:!|(2'
return getHibernateTemplate().find 9Vm
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(query, parameter); gg`{kN^r.a
} pl>b 6 |
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public PaginationSupport findPageByCriteria 9^!.!%6O$
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(final DetachedCriteria detachedCriteria){ *B3f ry
return findPageByCriteria |6Y:W$7k
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); k\O<pG[U
} Kk},
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public PaginationSupport findPageByCriteria "9xJ},:-
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(final DetachedCriteria detachedCriteria, finalint ={xRNNUj_
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startIndex){ ;:=j{,&dl[
return findPageByCriteria _AF$E"f@
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(detachedCriteria, PaginationSupport.PAGESIZE, 2e\"?y OD
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startIndex); IrZjlnht
} YA,.C4=s
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public PaginationSupport findPageByCriteria n*9QSyJN]
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(final DetachedCriteria detachedCriteria, finalint @2"uJ6o
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pageSize, #v(As)4^
finalint startIndex){ DTC
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return(PaginationSupport) {qHQ_ _Bl
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getHibernateTemplate().execute(new HibernateCallback(){ )vq}$W!:9
publicObject doInHibernate HBp??.r
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(Session session)throws HibernateException { n}Z%-w$K#
Criteria criteria = P\dfxR;8%
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detachedCriteria.getExecutableCriteria(session); pbG-uH^
int totalCount = N|mggz
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((Integer) criteria.setProjection(Projections.rowCount J <z
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()).uniqueResult()).intValue(); 7d.H8C2
criteria.setProjection $E[O}+L$#
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(null); d1#lC*.Sg
List items = cWnEp';.
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criteria.setFirstResult(startIndex).setMaxResults rWWpP<
"zw{m+7f,
(pageSize).list(); @wD#+Oz
PaginationSupport ps = O)^F z:
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new PaginationSupport(items, totalCount, pageSize, ]foS.D,
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startIndex); ?6*\M
return ps; `%|3c
} 1?)h-aN
}, true); .K^gh$z!
} q>%.zc[x
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public List findAllByCriteria(final BT(eU*m-
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DetachedCriteria detachedCriteria){ MA{ZmPm)
return(List) getHibernateTemplate I[A<e]uK
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().execute(new HibernateCallback(){ >Ch2Ep
publicObject doInHibernate Zah<e6L
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(Session session)throws HibernateException { @[FO;4w
Criteria criteria = iaMl>ua
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detachedCriteria.getExecutableCriteria(session); L7lpOy4k
return criteria.list(); M`7lYw\Or!
} @ebY_*
}, true); N\s-{7K
} k3LHLJZ#
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public int getCountByCriteria(final Foj|1zJS_
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DetachedCriteria detachedCriteria){ UH&1QV
Integer count = (Integer) kb$Yc)+R4
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getHibernateTemplate().execute(new HibernateCallback(){ OtAAzc!dQ
publicObject doInHibernate k{!9f=^
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(Session session)throws HibernateException { n2o)K;wW+
Criteria criteria = NHU5JSlB
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detachedCriteria.getExecutableCriteria(session); >`WQxkpy
return - ]/=WAOK
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criteria.setProjection(Projections.rowCount >t9DI
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()).uniqueResult(); MYJMZ3qBi
} 1e9~):C~W
}, true); J10 /pS
return count.intValue(); C5KUIOg
} k g(}%Ih
} asQ^33g z
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用户在web层构造查询条件detachedCriteria,和可选的 8YPX8d8u
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 \ %xku:
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PaginationSupport的实例ps。 s,mt%^x[
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ps.getItems()得到已分页好的结果集 non5e)w3@
ps.getIndexes()得到分页索引的数组 !mVq+_7]
ps.getTotalCount()得到总结果数 r^E(GmW
ps.getStartIndex()当前分页索引 vytO8m%U
ps.getNextIndex()下一页索引 7#&Q-3\:
ps.getPreviousIndex()上一页索引 y9T5
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 #
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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 lkp$rJ#6
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一下代码重构了。 zDm3$P=
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我把原本我的做法也提供出来供大家讨论吧: >CcDG
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首先,为了实现分页查询,我封装了一个Page类: 5|}u25J
java代码: k:mW ,s|a
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/*Created on 2005-4-14*/ IW}Wt{'m
package org.flyware.util.page; @eESKg(,
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/** .Y!dO@$:
* @author Joa ]R^xO;g'
* 1;,<UHF8N
*/ #<V5sgqS
publicclass Page { =|fB":vk
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/** imply if the page has previous page */ roi,?B_8
privateboolean hasPrePage; 7 > _vH]
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/** imply if the page has next page */ dtG>iJ
privateboolean hasNextPage; Gy6x.GX
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/** the number of every page */ 9B>P Qbs
privateint everyPage; }Q^*Zq9-
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/** the total page number */ pI_:3D
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privateint totalPage; zDxJK
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/** the number of current page */ J{5p4bkb
privateint currentPage; }dU!PZ9N)
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/** the begin index of the records by the current Xe\v6gbD
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query */ L|'B*
privateint beginIndex; 05jjLM'e
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/** The default constructor */ O sy_C<O
public Page(){ JPZH%#E(
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} j]mnH`#BL
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/** construct the page by everyPage 5CfD/}{:#I
* @param everyPage wT,=C'
* */ va"bw!zXo*
public Page(int everyPage){ 9@nd>B
this.everyPage = everyPage; * vqUOh
} l?xd3Z@7[
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/** The whole constructor */ V8pZr+AJ
public Page(boolean hasPrePage, boolean hasNextPage, MlbcJo3
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int everyPage, int totalPage, nYBa+>3BDf
int currentPage, int beginIndex){ ^nFP#J)_5
this.hasPrePage = hasPrePage; ?1LRR
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this.hasNextPage = hasNextPage; ^q|W@uG-(
this.everyPage = everyPage; d*U<Ww^q
this.totalPage = totalPage; *dC&*6Rx
this.currentPage = currentPage; ,.|/B^jV
this.beginIndex = beginIndex; [;~"ctf{
} nuA
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/** o?IrDQ2gmh
* @return Czy}~;_Ay
* Returns the beginIndex. yGV>22vv
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*/ gr@Ril^
publicint getBeginIndex(){ b9v<Jk
return beginIndex; x2OAkkH\]i
} /?S^#q>m%
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/** & Yx12B\
* @param beginIndex }iUpBn
* The beginIndex to set. fILvEf4b
*/ ~Jj~W+h
publicvoid setBeginIndex(int beginIndex){ Tgbq4xR(
this.beginIndex = beginIndex; -]n%+,3L
} y(^\]-fE
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/** Zzb?Nbf
* @return G9GLRdP
* Returns the currentPage. ekmWYQ
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*/ uK ,W
publicint getCurrentPage(){ :V_UJ3xf
return currentPage; F'B0\v=
} J`{o`>
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/** }O| 9Qb
* @param currentPage )me`Ud
* The currentPage to set. 2Je]dj4
*/ @*|T(068&
publicvoid setCurrentPage(int currentPage){ UG}2q:ST
this.currentPage = currentPage; P^<to(|
} D`KaIqLz
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/** *D9H3M[o#
* @return _,d<9 Y)
* Returns the everyPage. +!$`0v
*/ }WBHuVcZG
publicint getEveryPage(){ q1ZZ T"'
return everyPage; ojA !!Ru
} 64>CfU(
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/** MpIiHKQ
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* @param everyPage P|C5k5
* The everyPage to set. .;l`VWP
*/ d9%P[(yM^
publicvoid setEveryPage(int everyPage){ :AI%{EV-L
this.everyPage = everyPage; Z aS29}
} qOnGP{
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/** )8SWU)/
* @return Tf?`_jL
* Returns the hasNextPage. Ki&a"Fu3
*/ YBF$/W+=9|
publicboolean getHasNextPage(){ <$otBC/%
return hasNextPage; Htln <N
} &
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/** 1i'y0]f
* @param hasNextPage 1uB$@a\
* The hasNextPage to set. k,f/9e+#
*/ }d;6.~Gw
publicvoid setHasNextPage(boolean hasNextPage){ c&
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this.hasNextPage = hasNextPage; 5}Xi`'g,
} NSH4 @x
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/** ~P;A
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* @return U=U5EdN;
* Returns the hasPrePage. yf4L0.
*/ TY'61xWi
publicboolean getHasPrePage(){ NK(_ &.F
return hasPrePage; KC9e{
} %~PT7"4
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/** 4- Jwy
* @param hasPrePage K>b4(^lf
* The hasPrePage to set. U~;tk@
*/ +lhCF*@*N
publicvoid setHasPrePage(boolean hasPrePage){ %H2ios[UO
this.hasPrePage = hasPrePage; o
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} &g1\0t
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/** F[`dX
* @return Returns the totalPage. Y:, rN
* <gfRAeXA
*/ V*@Y9G
publicint getTotalPage(){ A^A)arJS
return totalPage; N;6o=^ic
} g|7o1{
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/** >xq.bG
* @param totalPage m8e()8lZ3
* The totalPage to set. Kfr1k
*/ kxJ[Bi#
publicvoid setTotalPage(int totalPage){ j0V/\Ep)T<
this.totalPage = totalPage; Im@OAR4,R
} ={V@Y-5T
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} 1?1Bz?EKF*
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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 k+w Ji
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个PageUtil,负责对Page对象进行构造: o[fg:/5)A
java代码: ( N};.DB1Y
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/*Created on 2005-4-14*/ ZDgT"53
package org.flyware.util.page; J'$NBws
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import org.apache.commons.logging.Log; n$r`s`}
import org.apache.commons.logging.LogFactory; G[yzi
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/** NR1M W^R
* @author Joa 3Z=yCec]
* D5snaGss9a
*/ x5BS|3W$a
publicclass PageUtil { X )tH23
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privatestaticfinal Log logger = LogFactory.getLog \\#D!q*
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(PageUtil.class); Hy&Z0W'l
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/** }RI_k&;
* Use the origin page to create a new page L%is"NZh
* @param page 76)"uqv1x
* @param totalRecords qpYgTn8l7
* @return 4=Ru{ewRV
*/ *YvtT(Gt
publicstatic Page createPage(Page page, int `@],J
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totalRecords){ v7wyQx+Q
return createPage(page.getEveryPage(), 'kt6%d2
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page.getCurrentPage(), totalRecords); _uMG?Sbx
} Qr$
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/** B #%QY\<X
* the basic page utils not including exception uhfK\.3
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handler ZY`9
* @param everyPage )LFbz#;Y
* @param currentPage v.Bwg7R3
* @param totalRecords 04Zdg:[3-!
* @return page M1-tRF
*/ V=8db%^
publicstatic Page createPage(int everyPage, int 8p%0d`sX
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currentPage, int totalRecords){ Dnw^H.
everyPage = getEveryPage(everyPage); $J4\jIipL
currentPage = getCurrentPage(currentPage); { im?tZ,
int beginIndex = getBeginIndex(everyPage, % akW43cE
QvZ"{
currentPage); 7wx=#
int totalPage = getTotalPage(everyPage, piM4grg
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totalRecords); Eu(QeST\
boolean hasNextPage = hasNextPage(currentPage, O00;0w u
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totalPage); A)]&L`s
boolean hasPrePage = hasPrePage(currentPage); K^fs#7
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returnnew Page(hasPrePage, hasNextPage, 1<_][u@
everyPage, totalPage, j_so s%-
currentPage, 62R";# K
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beginIndex); C;m"W5+
} H^n@9U;[K
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privatestaticint getEveryPage(int everyPage){ pmB
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return everyPage == 0 ? 10 : everyPage; rk1,LsZVS
} #E!^oZm<Z
#b[bgxm
privatestaticint getCurrentPage(int currentPage){ ,.9 lz
return currentPage == 0 ? 1 : currentPage; VNWB$mM.2
} iZn0B5]ikj
6o#/[Tz
privatestaticint getBeginIndex(int everyPage, int *G.vY#h
J "I,]
currentPage){ #8et91qw
return(currentPage - 1) * everyPage; >p-UQc
} Q ")Xg:
J;_4
3eS
privatestaticint getTotalPage(int everyPage, int 5m~9Vl-&
\bd KLcKI,
totalRecords){ {4 Yxh8
int totalPage = 0; HZ'rM5Kq
^.LB(GZ,
if(totalRecords % everyPage == 0) `(HD'f ud3
totalPage = totalRecords / everyPage; aU(.LC
else M99ku'
totalPage = totalRecords / everyPage + 1 ; Py
v>
;VKWY
return totalPage; Ps@']]4>W
} qg#YQ'vWte
_\\Al v.
privatestaticboolean hasPrePage(int currentPage){ UPGUJ>2Z
return currentPage == 1 ? false : true; pSlc (M>
} 9o>D
Uc
rn)Gx25
privatestaticboolean hasNextPage(int currentPage, i5TGK#3o
rB".!b
int totalPage){ ~o_JZ:
return currentPage == totalPage || totalPage == .*`^dt
Cl&mz1Y;]1
0 ? false : true; q~9-A+n
} PyfWIU7O
ra'/~^9
ljK?2z>
} k( 0; >)<i
n8Qv8
m,\+RUW'
2p, U ^h
rEWJ3*Hb
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。
gra6&&^"
Chnt)N`/B4
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 2*75*EQCH
}=EJM7sM|k
做法如下: TXi|
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7<WUjK|
Ee}|!n>
的信息,和一个结果集List: LA;f,CQ
java代码: AI3x,rk#
$[A^8[//
H(;@7dh
/*Created on 2005-6-13*/ h.K"v5I*
package com.adt.bo; yQ/O[(
o;6~pw%
import java.util.List; ~4+Y BN
1"CWEL`i
import org.flyware.util.page.Page; 4)e1K/PJ)
+H&/C1u
/** *~P| ? D'
* @author Joa ?S&
yF
*/ ^^}htg
publicclass Result { aR3jeB,=x
k5K5OpY
private Page page; 424iFc[
@>(JC]HtR
private List content; kAp#6->(q
v CsE|eMP
/** JfkEJk<
* The default constructor ~9o@1TO:v
*/ _5S0A0
public Result(){ KC}G_"f.$
super(); \\ItN
} *
;sz/.
6rbR0dSgx
/** %pjY ^tM/
* The constructor using fields @,oc%m
* 3q`f|r
* @param page ]R\L~Kr
* @param content F_:Wu,dUZ
*/ cr -5t4<jK
public Result(Page page, List content){ KJJ:fG8'
this.page = page; {wM<i
this.content = content; XE_Lz2H`
} !EKt$8W
Xbmsq,*]
/** M{orw;1Isy
* @return Returns the content. O-7)"
*/ TI8\qIW
publicList getContent(){ 5yt= ~
return content; l@SV!keQ
} "gNi}dB<]
1d+Kn Jy
/** 9LPXhxNwB
* @return Returns the page. >y8>OJ?A7-
*/ @nwVl8
public Page getPage(){ 4 ;_g9]
return page; }=f\WWJf0
} L44|/~
~6t<`&f
/** 7l-MVn_8
* @param content =U~53Tg
* The content to set. [@/p 8I
*/ g4q{
]
public void setContent(List content){ ;g8v7>p
this.content = content; Q[3hOFCX
} o% Q7 el$f
*>?N>f"
/** ncadVheKt
* @param page 7./-|#
* The page to set. 6wpu[
*/ P%&|?e~D^
publicvoid setPage(Page page){ 4xT /8>v2|
this.page = page; %x,HQNRDU
} 0J[B3JO@M
} tc.|mIvw
~pH!.|k-&
unFm~rcf
C8v
;uc3_J]
2. 编写业务逻辑接口,并实现它(UserManager, 9Bpb?
Ha]vG@?+
UserManagerImpl) pRlScD_};
java代码: 8[,R4@
9G6ZKqum
f'"PQr^9
/*Created on 2005-7-15*/ 7gOu|t
package com.adt.service; zN5};e}^v
IC"ktv bHz
import net.sf.hibernate.HibernateException; e]>=;Zn
,hJx3g5#n
import org.flyware.util.page.Page; )mAD <y+
p;7wH\c
import com.adt.bo.Result; x]hG2on!
E}%Pwr
/** U7/
=|Z
* @author Joa Nf* .r
*/ /W
f.Gt9[
publicinterface UserManager { ^; U}HAY
jC:D>
public Result listUser(Page page)throws dj9i*#F
-;8 a* F
HibernateException; OhaoLmA}6
N&G(`]
} k[ pk R{e
q~iEw#0-L
;#Qv
)kS*
bhg6p$411
6Rif&W.xy
java代码: GU1cMe
}h/7M
Ap"%%D^{:
/*Created on 2005-7-15*/ Q;y4yJ$wI
package com.adt.service.impl; U4Y)Jk
%< ;u
JP K
import java.util.List; vKPLh
%RwWyzm#\
import net.sf.hibernate.HibernateException; ow`F 7
xi<}n#
import org.flyware.util.page.Page; WSU/Z[\`H
import org.flyware.util.page.PageUtil; c;t3I},
pwSkw J]
import com.adt.bo.Result; {#@[ttw$U
import com.adt.dao.UserDAO; ~z41$~/
import com.adt.exception.ObjectNotFoundException; 1S+T:n
import com.adt.service.UserManager; mo4F\$2N
Y>E` 7n
/** zcOm"-E-
* @author Joa I:al[V2g
*/ .bV^u
publicclass UserManagerImpl implements UserManager { *GhV1# <
9P#kV@%(0c
private UserDAO userDAO; wr:-n
r-WX("Vvh
/** 8In~qf
* @param userDAO The userDAO to set. e<A>??h^
*/ }43qpJe8U
publicvoid setUserDAO(UserDAO userDAO){ K'E)?NW69
this.userDAO = userDAO; 0[uOKFgE
} 9&kPcFX B
0&kmP '
/* (non-Javadoc) /{[tU-}qJ
* @see com.adt.service.UserManager#listUser DtS7)/<T
Gf~^Xv!T
(org.flyware.util.page.Page) 8U]mr+
*/ "~K ph0-
public Result listUser(Page page)throws >wYmx4W>
UT 7'-
HibernateException, ObjectNotFoundException { S5L0[SZ$!
int totalRecords = userDAO.getUserCount(); ?%Q=l;W.
if(totalRecords == 0) s nNd7v.U6
throw new ObjectNotFoundException 3:sx%Ci/2
@b5$WKPX
("userNotExist"); Y@Ry
oJ
page = PageUtil.createPage(page, totalRecords); weGsjy(b]N
List users = userDAO.getUserByPage(page); ;3Z?MQe"NQ
returnnew Result(page, users); ^x(s!4d]
} I&^hG\D
l]
} X*Q<REDB
)*.rl
mZ?QtyljT
g>b{hkIXg
Az?^4 1r8
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 VS~+W=5}
~Kt+j
询,接下来编写UserDAO的代码: 4]
u\5K-
3. UserDAO 和 UserDAOImpl: jQfnc:'
java代码: NSzTl-eS
80gOh:
yS?5&oMl
/*Created on 2005-7-15*/ ET*:iioP
package com.adt.dao; u<Ch]m+
&I{5f-o*
import java.util.List; 6 pQo_l}
t="nmjQs
import org.flyware.util.page.Page; olHmRJ
NQOf\.#g
import net.sf.hibernate.HibernateException; j(pe6
rof9Rxxe-
/** ME5M;bz(
* @author Joa PyQ\O*
*/ G ,`]2'(@
publicinterface UserDAO extends BaseDAO { c[vFh0s"m
?l|&JgJ$
publicList getUserByName(String name)throws v(uNqX.BC
@y
eAM7
HibernateException; !,J]5$M
9m"EY@-
publicint getUserCount()throws HibernateException; ! bwy/A
kexvE 3
publicList getUserByPage(Page page)throws :[C|3KKe"
s,|v,,<+
HibernateException; W_
;b e
zSOZr2-
^a
} ?;_Mx al'
+QSH*(,
X7?14W
-2C^M> HZ
r"VNq&v]9
java代码: f$?`50D"1
9zLeyw\
pG v*{.
/*Created on 2005-7-15*/ |$GPJaNqa
package com.adt.dao.impl; *^Z -4
GJF
,w{J
import java.util.List; y"_rDj`
O^3XhTW^\~
import org.flyware.util.page.Page; aOUTKyR ~
*iSE)[W
import net.sf.hibernate.HibernateException; g`6I, 6G
import net.sf.hibernate.Query; .F\[AD 5
Iq{/-,v
import com.adt.dao.UserDAO; Nk$|nn9#'
J'wJe,
/** >@Na6BH5v
* @author Joa d]?fL&jr
*/ 0yb9R/3.
public class UserDAOImpl extends BaseDAOHibernateImpl YEB7X>p#
--vJR/-
implements UserDAO { +5:9?&lH
wj Kc!iB
/* (non-Javadoc) ')WS :\J
* @see com.adt.dao.UserDAO#getUserByName GN+,9
n(Um/
(java.lang.String) sr<\fW
*/ lI9|"^n7F
publicList getUserByName(String name)throws ZV-Yq !|t
,L\KS^>
HibernateException { 9S5C{~P4
String querySentence = "FROM user in class +\.0Pr
JFkx=![
com.adt.po.User WHERE user.name=:name"; R@IwmJxX
Query query = getSession().createQuery Z3X9-_g
lvR>%I0`*
(querySentence); rF/<}ye/4M
query.setParameter("name", name); &mba{O
return query.list(); |Fx~M,Pzg
} PaDm"+H@
ogdgLTi
/* (non-Javadoc) - C8VDjf9
* @see com.adt.dao.UserDAO#getUserCount() "2"2qZ*h}
*/ 8&7zV:=
publicint getUserCount()throws HibernateException { AbX#wpp!
int count = 0;
"'Q~&B;@
String querySentence = "SELECT count(*) FROM +4[Je$qYa
0.U-
tg0
user in class com.adt.po.User"; (J
j'kW6G6
Query query = getSession().createQuery iW[%|ddk
_6aI>b#yL
(querySentence); ?nM]eUAP
count = ((Integer)query.iterate().next TH~"y
j:2*hF!E
()).intValue(); l%
{<+N
return count; d @b ]/
} e,*@+E\4
aL8Z|*
/* (non-Javadoc) 7aHP;X~0
* @see com.adt.dao.UserDAO#getUserByPage )s
?Hkn
| tFg9RT
(org.flyware.util.page.Page) ~#=70
*/ Ece=loV*l
publicList getUserByPage(Page page)throws hz-^9U
@M(+YCi:e@
HibernateException { ~yY5pnJ
String querySentence = "FROM user in class {w v{"*Q9Q
i~{ 0>"9
com.adt.po.User"; ERfSJ
Query query = getSession().createQuery -Y>QKS
'lgS;ItpKu
(querySentence); VH~ZDZ1P
query.setFirstResult(page.getBeginIndex()) `I(5Aj"
.setMaxResults(page.getEveryPage()); l~x
6R~q
return query.list(); 2:1
kSR^Ky
} A-u}&}l<
8?hj}}H
} YG#{/;^nm)
cM=_i{c
M1K[6V!
=BeJ.8$@VC
4B-+DH>{6
至此,一个完整的分页程序完成。前台的只需要调用 Fw%S%*B8g
e#ne 5
userManager.listUser(page)即可得到一个Page对象和结果集对象 [tJp^?6*
6^z):d#u
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=*[3
N1dM,H
webwork,甚至可以直接在配置文件中指定。 io7Zv*&T0
bKr73S9
下面给出一个webwork调用示例: 0E^S!A7
java代码: |_16IEJ
dF+:9iiAm
r3~YGY
/*Created on 2005-6-17*/ =^w:G =ymS
package com.adt.action.user; w2V:g$~,
2&2t8.<
import java.util.List; ;Hu`BFXyD
I5W#8g!{
import org.apache.commons.logging.Log; i(S}gH4*o
import org.apache.commons.logging.LogFactory; bG]?AiWr
import org.flyware.util.page.Page; 3Io7!:+
xp]_>WGq
import com.adt.bo.Result; B~u`bn,iQ
import com.adt.service.UserService; o^x,JT
import com.opensymphony.xwork.Action; "X-"uIc
2nI^fVR%\
/** uh3<%9#\k
* @author Joa H `_{n<
*/ 5Qxm\?0J
publicclass ListUser implementsAction{ L ?S#3@Pa
-'j|U[&N\
privatestaticfinal Log logger = LogFactory.getLog 8q|T`ac+N
)fbYP@9>a
(ListUser.class); ?b?YiK&yz
AN+S6t
private UserService userService; o_.`&Q6n
vk3C&!M<a
private Page page; Bv^5L>JZ/
.QDeS|l
privateList users; +wm%`N;v<
,BlNj^5f
/* knRs{1}Pw{
* (non-Javadoc) ^x}k1F3
* B?;P:!/1
* @see com.opensymphony.xwork.Action#execute() Jy-V\.N>s
*/ rf
=Wq_
publicString execute()throwsException{ !4T7@V`G
Result result = userService.listUser(page); N?c!uO|h|
page = result.getPage(); +LaR_n[
users = result.getContent(); (CY#B%*
return SUCCESS; g 4lk
} 5:SS2>~g
}%S#d&wh$_
/** w!52DBOe+
* @return Returns the page. ZY8:7Q@P>
*/ o=C'u
public Page getPage(){ 4u7^v1/
return page; )_1;mc8B
} +.66Ky`|[
WdT iao,r
/** luCwP
* @return Returns the users. 7K
/qu J
*/ {w<"jw&2
publicList getUsers(){ F;Bq[V)R
return users; SH6T\}X:
} i:
VMCNH
IkgRZ{Y
/** x\K,@
* @param page v}Kj+9h
* The page to set. dg@'5.ApPu
*/ Ypx"<CKP}
publicvoid setPage(Page page){ 4.q^r]m*
this.page = page; *+j r? |
} noO#o+
Jg#
)^j62uv
/** >ui;B$=
* @param users 4ms"mIt
* The users to set. Tvd: P^C
*/ oGz5ZDa#
publicvoid setUsers(List users){ Pk&sY'
this.users = users; .hK:-q,
} 2X 0<-Y#'
@8lT*O2j
/** yG,uD!N]|
* @param userService F<Ig(Wl#az
* The userService to set. F_nXsKem
*/ y*#+:D]o*
publicvoid setUserService(UserService userService){ 1n~^@f#`
this.userService = userService; PgYIQpV
} &|fWtl;43
} 'oF ('uR
oe[f2?-
:O]US)VSj
aJ
J63aJ
f;obK~b[
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, }[SYWJIc
O<y65#68Z
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 SL?YU(a
!>)o&sM
么只需要: PyM59v
java代码: TPNKvv!s
ev1:0P
rYrvd[/*&(
<?xml version="1.0"?> [rReBgV
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork \/R $p
0t6DD
1.0//EN" "http://www.opensymphony.com/xwork/xwork- DJ|lel/'
=!IoL7x
1.0.dtd"> _a zJ>
mi@ni+2Tn
<xwork> !JA//{?
`pfRY!
<package name="user" extends="webwork- &A~hM[-
hY|-l%2f
interceptors"> 05o<fa 2HE
W;|%)D)y
<!-- The default interceptor stack name @nIoIz
D~
8+8L'Yv;
--> z+<ofZ(.
<default-interceptor-ref 6bT>x5?
I !O5+Er
name="myDefaultWebStack"/> ;3+_aoY
HSEz20s
<action name="listUser" ]E#W[6'VtB
c"/Hv
class="com.adt.action.user.ListUser"> a7jE*%f9
<param mEyIbMci
=Jswd
name="page.everyPage">10</param> :}-izd)/j
<result C~T*Wlk
ff
6x4t
name="success">/user/user_list.jsp</result> 3)hQT-)
</action> +HlZ?1g
9hjzOJPuga
</package> s\0,@A
C@u}tH
)
</xwork> Op:$7hv
Bv#?.0Ez;
w|61dB
EF'8-*
h;):TFiC
e <+b?@}=B
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 5aNvGI1
Jv?EV,S/e
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 2)/!+`a
g1@rY0O
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 9(lcQuE9
Cng_*\=O
oj@=Cq':-
ZtY?X- 4_
jtgj h\Nt
我写的一个用于分页的类,用了泛型了,hoho `x;m@\R
}yw>d\] f
java代码: S_38U
xXSfYW
0bOT&Z^
package com.intokr.util; X6xs@tgQ
FcyFE~>2
import java.util.List; cUn>gT
2 a*+mw
/** O+]'*~a
* 用于分页的类<br> )nrYxxN
* 可以用于传递查询的结果也可以用于传送查询的参数<br> k]~$AaNq
* zR)/h
* @version 0.01 a*uG^~
).
* @author cheng t:b}Mo0
*/ |XV`A)=f
public class Paginator<E> { Z+=-)&L
privateint count = 0; // 总记录数 \["I.gQ
privateint p = 1; // 页编号 )a9C3-8Y'
privateint num = 20; // 每页的记录数 rPt
privateList<E> results = null; // 结果 bt Bu[;
v#e*RI2}
/** 59i2*<k
* 结果总数 >=;hnLu
*/ M{SJ8+G
publicint getCount(){ b1QHZY\g{
return count; u=Xpu,q
} [Y
j:H
Gte\=0Wr
publicvoid setCount(int count){ VP<LY/'f
this.count = count; \fp'=&tp~a
} tH#t8Tq5x
| GN/{KH]
/** MhJA8|B6|
* 本结果所在的页码,从1开始 <p-@XzyE
* [f}`reRlZ
* @return Returns the pageNo. FR>[g`1
*/ c6AwO?x/
publicint getP(){ C|[x],JCS
return p; ddd2w
} 1(RRjT9
I:6XM?
/** eu":\ks
* if(p<=0) p=1 Z?V vFEt%
* <PM.4B@
* @param p U@D\+T0
*/ Spin]V
publicvoid setP(int p){ C](djkA$
if(p <= 0) pG'?>]Rt4
p = 1; 2EYWX!Bx
this.p = p; Y*{5'q+2
} Ql9>i;AGV
1_l)$"
/** pF9WKpzE
* 每页记录数量 u:tcL-;U
*/ ei"c|/pO
publicint getNum(){ [j0jAl
return num; J8ScKMUN2
} @(+\*]?^&
\DWKG~r-%
/** )>"pm{g2
* if(num<1) num=1 1$`|$V1
*/ ,X;$-.
publicvoid setNum(int num){ ydj*Jy'
if(num < 1) g^7zDU&'
num = 1; DtJ3`Jd
this.num = num; yE(<F2
} lY2~{Y|4s
u J]uz%
/** 2%J] })
* 获得总页数 [:qJ1^U U
*/ f6nuh&!-
publicint getPageNum(){ UZmo?&y
return(count - 1) / num + 1; d|)ARRW
} (44L8)I.D
)>U"WZ'<
/** #2$wI^O
* 获得本页的开始编号,为 (p-1)*num+1 R(,m!
*/ 4'`H H
publicint getStart(){ (`4&Y-
return(p - 1) * num + 1; L3'isaz&^
} xg 8R>j
:RwURv+kT
/** hwQ|'^(@O
* @return Returns the results. ]6s/y
*/ :SWrx MT
publicList<E> getResults(){ /-t!)_zvw
return results; a>9_#_hI
} <:T/hm$
[>\e@ =
public void setResults(List<E> results){ adRIg:2
this.results = results; 3x7fa^umR
} 5wha _Yet
I+S fZ:q^
public String toString(){ <#199`R
StringBuilder buff = new StringBuilder /q,=!&f2
H8B2{]HAt
(); ;uv$>Fauk
buff.append("{"); !VsdKG)
buff.append("count:").append(count); +nim47
buff.append(",p:").append(p); Xwjm T
buff.append(",nump:").append(num); s&Al4>}.f
buff.append(",results:").append cIC/3g}]
{'B(S/Z7
(results); qh&q<M
buff.append("}"); Z;BEUtR
c
return buff.toString(); rdtzz#7
} g1_z=(i`Z
E:+r.r"Y
} 6@3v+Vf'
!!8;ZcL}Z
ZX.,<vumSy