Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Q~CpP9%
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 1#kawU6[]
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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 S&`O\!NF
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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]UA0[8X
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分页支持类: z+2u-jG
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java代码: OUKj@~T
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package com.javaeye.common.util; _.hIv8V
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import java.util.List; zVn* !c
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publicclass PaginationSupport { vzQyE0T/
@YbZ8Uc
publicfinalstaticint PAGESIZE = 30; Hm<M@M$aG
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privateint pageSize = PAGESIZE; gtl;P_
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privateList items; {K6Kx36
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privateint totalCount; >cSi/a,L
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privateint[] indexes = newint[0]; %!#rrt,F
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privateint startIndex = 0; F F(^:N
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public PaginationSupport(List items, int %j!z\pa
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totalCount){ ^$ZI>L0+
setPageSize(PAGESIZE); "&s9cO.H
setTotalCount(totalCount); Z@8MhJ
setItems(items); Ty(yh(oYF`
setStartIndex(0); W=!F8g|Qz
} W=(MsuirO
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public PaginationSupport(List items, int Udg&
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totalCount, int startIndex){ }b<87#Nb9R
setPageSize(PAGESIZE); ArLz;#AOn
setTotalCount(totalCount); yg.\^C
setItems(items); K7y!s :rg!
setStartIndex(startIndex); u_hE7#i
} yDDghW'\WU
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public PaginationSupport(List items, int 20S9/9ll
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totalCount, int pageSize, int startIndex){ Bl:{p>-q
setPageSize(pageSize); Nt?2USTs-
setTotalCount(totalCount); @)S sKk|
setItems(items); zT2F&y
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setStartIndex(startIndex); P((S2"D<4
} 19pND
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publicList getItems(){ U`HXsq
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return items; AD0ptHUBa
} 1
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publicvoid setItems(List items){ m[//_TFf]
this.items = items; UA1]o5K
} jcT{ugpq
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publicint getPageSize(){ {yul.m
return pageSize; iDyMWlV
} yd{Y}.
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publicvoid setPageSize(int pageSize){ ski1f
this.pageSize = pageSize; MxFt;GgE8
} !-
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publicint getTotalCount(){ $4#=#aKW.
return totalCount; p3>Q<
} mdmZ1:PBM
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publicvoid setTotalCount(int totalCount){ a
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if(totalCount > 0){ /gMa" 5?,
this.totalCount = totalCount; *B)Jv9
int count = totalCount / ({ :yw
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pageSize; ~5XL@j I^
if(totalCount % pageSize > 0) _#y(w%
count++; L<{OBuR
indexes = newint[count]; P 'FPe55F
for(int i = 0; i < count; i++){ t1*BWY
indexes = pageSize * 1( QWt
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i;
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} ySPlyhGF
}else{ WOe{mwhhj
this.totalCount = 0; 24.7S LXO
} 4w?]dDyc%
} @ ~0G$
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publicint[] getIndexes(){
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return indexes; 62k9"xSH
} '? !7 Be
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publicvoid setIndexes(int[] indexes){ xIq"[?m
this.indexes = indexes; &+|jJ{93z
} 75^)Ni
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publicint getStartIndex(){ 5Tcl<Y6l
return startIndex; [TpA26#TTO
} tDuUAI54
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publicvoid setStartIndex(int startIndex){ f6dE\
if(totalCount <= 0) E@'CU9Fo
this.startIndex = 0; d=.n|rS4
W
elseif(startIndex >= totalCount) jN5} 2 p*
this.startIndex = indexes y5Z<uwXc
wj";h Aw
[indexes.length - 1]; _dJVnC1 !
elseif(startIndex < 0) o0-fUCmC
this.startIndex = 0; eKU@>5
else{ ,/[dmoe
this.startIndex = indexes l{D,O?`Av
G*{ u(x(
[startIndex / pageSize]; f"Vm'0r
}
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} sEgeS9a{
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publicint getNextIndex(){ f;_K}23
int nextIndex = getStartIndex() + 1,*Z_ F=y
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pageSize; RfVV(X
if(nextIndex >= totalCount) hBY h90]
return getStartIndex(); ,sRrV $,"
else )sz2 9
return nextIndex; 66Cj=n5
} L3hxe]mr
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publicint getPreviousIndex(){ G-Ml+@e>
int previousIndex = getStartIndex() - X=!n,=xI
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pageSize; c+G :@%
if(previousIndex < 0) l5N\>q
return0; ]J"+VZ_"I
else *9U4^lJjn
return previousIndex; Xj@
} 1rvf\ [
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} *t]&b ;=gE
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抽象业务类 zLIa! -C
java代码: ?#{2?%_
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/** N6m*xxI{
* Created on 2005-7-12 (
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*/ xZ{|D
package com.javaeye.common.business; {0Ol/N;|D
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import java.io.Serializable; kAe-d
import java.util.List; I!i#=
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import org.hibernate.Criteria; #t9=qR~"
import org.hibernate.HibernateException; rc{[\1 -N
import org.hibernate.Session; jP7+s.j>
import org.hibernate.criterion.DetachedCriteria; %imBGh
import org.hibernate.criterion.Projections; S|5lx7
import (k2J{6]
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org.springframework.orm.hibernate3.HibernateCallback; odT7Gq
import Le$u$ulS
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org.springframework.orm.hibernate3.support.HibernateDaoS 3~1lVU:
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upport; R.WsC bU
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import com.javaeye.common.util.PaginationSupport; 2
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public abstract class AbstractManager extends @ 6V H%
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HibernateDaoSupport { i:N^:%
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privateboolean cacheQueries = false; ~9>[ U%D
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privateString queryCacheRegion; =A&*SE o5
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publicvoid setCacheQueries(boolean !Pjg&19
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cacheQueries){ EvardUB)
this.cacheQueries = cacheQueries; ~b<4>"7y.
} X]^E:'E!
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publicvoid setQueryCacheRegion(String <}'B-k9
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queryCacheRegion){ Ru\Lr=9
this.queryCacheRegion = JX,#W!d
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queryCacheRegion; YM/3VD
} rOf
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publicvoid save(finalObject entity){ rZCAj
getHibernateTemplate().save(entity); X\)KVn`
} Y>!W&Gtu
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publicvoid persist(finalObject entity){ oHFDg?Z`
getHibernateTemplate().save(entity); 58ZiCvqv
} i}{Q\#=#
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publicvoid update(finalObject entity){ AT'$VCYC(
getHibernateTemplate().update(entity); +jZg%$Q!#
} N#!1@!2BN
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publicvoid delete(finalObject entity){ KGLhl;a
getHibernateTemplate().delete(entity); >oaEG5%d
} L<>NL$CrN
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publicObject load(finalClass entity, ]Sx=y<
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finalSerializable id){ F?AfB[PM
return getHibernateTemplate().load p:>?
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(entity, id); ITY!=>S-
} Hh=::Bi
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publicObject get(finalClass entity, >{)#|pWU
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finalSerializable id){ |a:VpM
return getHibernateTemplate().get Uht:wEr
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(entity, id); 0g uc00IN
} .wOLi Ms
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publicList findAll(finalClass entity){ Wk#-LkI
return getHibernateTemplate().find("from t SLl'XeN
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" + entity.getName()); u,9U0ua@;
} &fhurzzAm
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publicList findByNamedQuery(finalString e>9{36~jh
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namedQuery){ -#M~NbI,
return getHibernateTemplate l'8TA~
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().findByNamedQuery(namedQuery); NJ!#0[@C
} !fjU?_[S
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publicList findByNamedQuery(finalString query, h#;K9#x6
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finalObject parameter){ _rh.z_a7w
return getHibernateTemplate BCB/cBE
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d2[pp
().findByNamedQuery(query, parameter); Y]0y
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} a8P6-)W
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publicList findByNamedQuery(finalString query, g' U^fN
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finalObject[] parameters){ uKzz/Y{
return getHibernateTemplate z`7C)p:
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().findByNamedQuery(query, parameters); Ybg`Z
} =+\oL!^
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publicList find(finalString query){ (pNng"/
return getHibernateTemplate().find V]cY+4Y
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(query); ~m&oa@*=y
} u<2sb;a
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publicList find(finalString query, finalObject .]l2)OlLQ
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parameter){ Gnq~1p5^
return getHibernateTemplate().find 2b` M(QL
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(query, parameter); 0t0:soZx
}
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public PaginationSupport findPageByCriteria pD/S\E0@t
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(final DetachedCriteria detachedCriteria){ DYl{{L8@
return findPageByCriteria `t2! M\)
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); He23<hd!
} Y)RikF >
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public PaginationSupport findPageByCriteria .H.v c_/
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(final DetachedCriteria detachedCriteria, finalint py4_hj\v
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startIndex){ hY9u#3
return findPageByCriteria EZW?(%b>H
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(detachedCriteria, PaginationSupport.PAGESIZE, 4(ZV\}j1
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startIndex); E/ )+hK&
} ( mMz]b5
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public PaginationSupport findPageByCriteria ["/x~\c'N
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(final DetachedCriteria detachedCriteria, finalint [D\AVx&
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pageSize, 06;{2&ju<
finalint startIndex){ #O
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return(PaginationSupport) aoX$,~oI5
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getHibernateTemplate().execute(new HibernateCallback(){ r&RSQHa)
publicObject doInHibernate ^Y |s^N
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(Session session)throws HibernateException { ~`.%n7
Criteria criteria = |XZf:}q5:
u9(AT>HxT
detachedCriteria.getExecutableCriteria(session); 9$i`B>C~
int totalCount = ;& +75n
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((Integer) criteria.setProjection(Projections.rowCount Dh<e9s:
T]`"
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()).uniqueResult()).intValue(); (5
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criteria.setProjection XPKcF I=
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(null); ;zODp+4@Q
List items = "(GeW286k
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criteria.setFirstResult(startIndex).setMaxResults IgJC>;]u
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(pageSize).list(); !y.7"G*
PaginationSupport ps = 3\ed4D
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new PaginationSupport(items, totalCount, pageSize, 2ra4t]f6
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startIndex); qMOD TM~+
return ps; `!N?#N:b)
} ;GSj}Nq
}, true); eNb =`
} s5e}X:
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public List findAllByCriteria(final dZZ/(oE>
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pg
DetachedCriteria detachedCriteria){ f0+
return(List) getHibernateTemplate DK;-2K
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().execute(new HibernateCallback(){ |1R@Jz`
publicObject doInHibernate >{Q2S
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(Session session)throws HibernateException { 'z/hj>B<
Criteria criteria = XlPy(>
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detachedCriteria.getExecutableCriteria(session); %3wK.tR
return criteria.list(); ^gImb`<6-
} Sb.;$Be5g
}, true); M*%Z5,Tc
} *d 4D9(
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public int getCountByCriteria(final (X/JXu{
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DetachedCriteria detachedCriteria){ 62) F
Integer count = (Integer) v80e]M!
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getHibernateTemplate().execute(new HibernateCallback(){ =1C9lKm
publicObject doInHibernate %VCHM GP=
t*#T~3p
(Session session)throws HibernateException { J5wq}<8
Criteria criteria = Zh*I0m
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detachedCriteria.getExecutableCriteria(session); ifUgj8i_
return gC_U7a w
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criteria.setProjection(Projections.rowCount I6+5 mv\
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()).uniqueResult(); '4EJ_Vhztc
} $1YnQgpT
}, true); nM#\4Q[}Jh
return count.intValue(); QMP:}
} ?uQpt(
} lOZZ-
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用户在web层构造查询条件detachedCriteria,和可选的 wbTw\b=
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 x\WKsc
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PaginationSupport的实例ps。 "Z
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ps.getItems()得到已分页好的结果集 >
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ps.getIndexes()得到分页索引的数组 ? T9-FGW
ps.getTotalCount()得到总结果数 Yyf8B
ps.getStartIndex()当前分页索引 tP3Upw"U
ps.getNextIndex()下一页索引 <?+\\Z!7
ps.getPreviousIndex()上一页索引 Ad(j&P
idHBz*3~ps
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 TeHR,GB
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 ;-59#S&?tB
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一下代码重构了。 &12.|
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我把原本我的做法也提供出来供大家讨论吧: R"jX9~3Ln
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首先,为了实现分页查询,我封装了一个Page类: z?7pn}-
java代码: t2>Vj>U
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/*Created on 2005-4-14*/ /) N[tv2
package org.flyware.util.page; }0:=)e
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/** xGjEEBL
* @author Joa [dL#0~CL$
* rLVS#M#&e>
*/ q*>`HTPcU
publicclass Page { O3S_P]{*ny
yA~W|q(/V
/** imply if the page has previous page */ N7XRk=J
privateboolean hasPrePage; Y%2<}3P
J}BS/Tr}=
/** imply if the page has next page */ 9i n& \
privateboolean hasNextPage; b1-JnEc
=KkHck33
/** the number of every page */ JVRK\A|R
privateint everyPage; 6u7>S?
nCt:n}+C7
/** the total page number */ >#SQDVFf
privateint totalPage; ."dmL=
X=lOwPvP
/** the number of current page */ |VIBSty2d
privateint currentPage; k z<We/
VgOj#Z?K
/** the begin index of the records by the current @X:P`?("^
IL\#!|>
query */ {JMFCc[
privateint beginIndex; zUeS7\(l
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/** The default constructor */ !RV}dhI
public Page(){ P7Kp*He)
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} bEbnZ<kz*
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/** construct the page by everyPage |+%K89W
* @param everyPage 0]&~ddL
* */ $w{#o E
public Page(int everyPage){ fDf:Jec`[
this.everyPage = everyPage; ]*?qaIdqu
} |:C=j/f
!ce:S!P
/** The whole constructor */ 1qtu,yIf
public Page(boolean hasPrePage, boolean hasNextPage, in$Pk$ c
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U
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int everyPage, int totalPage, :Fm)<VN"
int currentPage, int beginIndex){ L9(fa+$+#
this.hasPrePage = hasPrePage; Ga"t4[=I
this.hasNextPage = hasNextPage; p3&w/K{L6w
this.everyPage = everyPage; G}d@^9FkE
this.totalPage = totalPage; wUab)L
this.currentPage = currentPage; J=ZNx;{6
this.beginIndex = beginIndex; <^{|5u
} |d&a&6U:
*22}b.)
/** >zVj+
* @return QOMh"wC3
* Returns the beginIndex. {'T=&`&OF
*/ Q
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publicint getBeginIndex(){ 1t6VS 3
return beginIndex; "9aiin
} ;
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/** |}t[-a
* @param beginIndex ;vnG
* The beginIndex to set. \^i/:
*/ C[gy{40}
publicvoid setBeginIndex(int beginIndex){ CNQ>J`4
this.beginIndex = beginIndex; yc?+L;fN
} C[z5&
x2
t[|^[%i
/** q3n(Z
* @return 1)U%p
* Returns the currentPage. n]jZ2{g+
*/ >d%;+2
publicint getCurrentPage(){ \hoYQK j
return currentPage; ;b-Y$<
} ^^1rjh1I
QE1DTU
/** w-LMV>+6|
* @param currentPage l.Iov?e1S
* The currentPage to set. |hk?'WGc`0
*/ gq\ulLyOeZ
publicvoid setCurrentPage(int currentPage){ $n.oY5=\
this.currentPage = currentPage; XDRw![H,~
} M:YtW5{
kWZ?86!
/** =J:6p-\*
* @return $# klgiL
* Returns the everyPage. v2][gn+58
*/ WW\t<O;z
publicint getEveryPage(){ k` cz$>
return everyPage; :+: vBrJm
} eD2u!OKW!
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/** Fg;V6s/>ts
* @param everyPage =8#$'1K,v
* The everyPage to set. w,f1F;!q1
*/ '7Q5"M'
publicvoid setEveryPage(int everyPage){ z]:{ruvH
this.everyPage = everyPage; 9Kf# jZ
} ;n0VF77>O
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/** JL.noV3q$
* @return qn=~4rg]R
* Returns the hasNextPage. I*hCIy#;
*/ g:V8"'
publicboolean getHasNextPage(){ ]rU$0)VN
return hasNextPage; [Vzp D 4
} FtHR.S=u
IY jt*p5
/** rXgU*3RG
* @param hasNextPage b5NPG N
* The hasNextPage to set. >LS*G
qjq
*/ IWc?E
publicvoid setHasNextPage(boolean hasNextPage){ tj<a , l
this.hasNextPage = hasNextPage; [Tmpj9!q
} ZxW4 i
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/** Ky(=O1Ufu
* @return z86[_l:
* Returns the hasPrePage. lM/)<I\8
*/ P4H%pm{-
publicboolean getHasPrePage(){ C5k\RS9
return hasPrePage; E3%:7MB
} q3Tp/M.
! 3&_#VO
/** fiG/"/u
* @param hasPrePage p{c+ +P5
* The hasPrePage to set. EkWipF(
*/ E6
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publicvoid setHasPrePage(boolean hasPrePage){ H!uB&qY
this.hasPrePage = hasPrePage; [3&Y* W
} GP|G[
6<E4?<O%
/** wlvh DJ
* @return Returns the totalPage. kta`[%KmIZ
* e(t,~(
*/ ;}/@ar7s3
publicint getTotalPage(){ ~x}/>-d
return totalPage; #A&(b}#:o
} Jng,:$sZ
iobL6SUZ
/** WrzyBG_
* @param totalPage UBN^dbP*
* The totalPage to set. OanH G
*/ kaK0'l2%
publicvoid setTotalPage(int totalPage){ *cNqgw#\qL
this.totalPage = totalPage; `/+%mKlC|[
} R['k&jyi
">?ocJ\9
} ^7cZ9/3
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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 N001c)*7Q
IO, kGUS
个PageUtil,负责对Page对象进行构造: f(Hh(
java代码: Lbo8>L(
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/*Created on 2005-4-14*/ m@qM|%(0x
package org.flyware.util.page; Qf?5"=:#
KZK9|121
import org.apache.commons.logging.Log; g\Gx
oR
import org.apache.commons.logging.LogFactory; w>RBth^p
a-P'h1hbH
/** "ZuhN(-`
* @author Joa {|{}]B
* y(I_ 6+B^
*/ ]{`
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publicclass PageUtil { In%K
W> ZL[BQ
privatestaticfinal Log logger = LogFactory.getLog A..,.
?2#!63[Kg
(PageUtil.class); h}vzZZ2,
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/** b?h)~j5
* Use the origin page to create a new page ) ?AlQA
* @param page ppwjr
+
* @param totalRecords Y6_%HYI$
* @return < C{-ph
*/ `vkNp8|
publicstatic Page createPage(Page page, int aFZu5-=x
v^Vr^!3
totalRecords){ 8(.DI/
return createPage(page.getEveryPage(), 7N@4c
gnAM}
page.getCurrentPage(), totalRecords); ,34|_
} !^o(?1
.Pp;%
/** >g ):xi3qK
* the basic page utils not including exception @y{i.G
994
handler w&A&BE^O/
* @param everyPage me-:A:si
* @param currentPage 3ug|H
* @param totalRecords HwE1cOT
* @return page 50 s)5G#
*/ }~8/a3
publicstatic Page createPage(int everyPage, int ^uU'Qc4S=
--ED]S
8
currentPage, int totalRecords){ [dszz7/L
everyPage = getEveryPage(everyPage); 5<%]6c x}
currentPage = getCurrentPage(currentPage); # g.J,L
int beginIndex = getBeginIndex(everyPage, XIv{jzgF
GCw<jHw
currentPage); Kp_L\'.I5$
int totalPage = getTotalPage(everyPage, @<GVY))R8
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totalRecords); LGxQ>f[V
boolean hasNextPage = hasNextPage(currentPage, .JR"|;M}
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totalPage); >JNK06T
boolean hasPrePage = hasPrePage(currentPage); qr5ME/)z
hq5=>p
returnnew Page(hasPrePage, hasNextPage, Ihe/P {t]J
everyPage, totalPage, /+FZDRf!r
currentPage, f z)i9D@
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beginIndex); b4_"dg~gK
} <Pg]V:=g'
\ 2Jr(?U
privatestaticint getEveryPage(int everyPage){ (h"Yw
return everyPage == 0 ? 10 : everyPage; v-*CE[
} +y+-~;5iv
{gSR49!Q
privatestaticint getCurrentPage(int currentPage){ IIN"'7Z^R
return currentPage == 0 ? 1 : currentPage; M6ol/.G[
} *`}4]OGv.
6Y#-5oEu/
privatestaticint getBeginIndex(int everyPage, int Vrz6<c-'B
Q77iMb]
currentPage){ NW}kvZ
return(currentPage - 1) * everyPage; W#pA W
} 7l-`k
u>~G)lx%
privatestaticint getTotalPage(int everyPage, int $EHnlaG8r
` ]*KrY
totalRecords){ o=!3=2@dh
int totalPage = 0; hFC4CqBV
.Yxx
if(totalRecords % everyPage == 0) yPKDn.1
totalPage = totalRecords / everyPage; vt;<+"eps
else a '/yN{?p
totalPage = totalRecords / everyPage + 1 ; 69Y>iPRU
@IaK:
return totalPage; .O\z:GrSZz
} R:*I>cRs
6B4s6
privatestaticboolean hasPrePage(int currentPage){ vXUrS+~x
return currentPage == 1 ? false : true; XxW~4<r
} (t.pM P4
yFt'<{z[nL
privatestaticboolean hasNextPage(int currentPage, cZ(7/Pl
b;!oPT
int totalPage){ st;.Po[h
return currentPage == totalPage || totalPage == dXKv"*7l
Dh*>361y-
0 ? false : true; GHQa{@m2V
} nwd
02tu
1goK>=-^
J~Gq#C^e
} WMB~?
EDhv
&hmyfH&S
PVAs# ~
{5+t\~q$
s'LY)_n
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。 v})0zz?,1
Q+ ;6\.#r
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 YW@Ad
6gS<h\h0
做法如下: =bUVGjr%96
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 !<"H73?fl
-9"hJ4
的信息,和一个结果集List: f-5vE9G3y7
java代码: ^>?gFvWB%
D7%`hU
S3-3pJ]~Zk
/*Created on 2005-6-13*/ [YT"UVI
package com.adt.bo; f\oB/
XUUl*5^
import java.util.List; ;4nz'9+
EthnI7Y
import org.flyware.util.page.Page; *Yk3y-
w{[OtGIi3
/** RdlcJxM
* @author Joa EEQW$W1@
*/ /}?"O~5M"
publicclass Result {
R1'bB"$
]}/LNO*L"
private Page page; ;o;P2}zD
,HXY|fYr
private List content; brN:Ypf-e
4LYeacL B
/** wU_e/+0h
* The default constructor Q7`}4c)
*/ qw[)$icP
public Result(){ [Q,E(
s
super(); hV_eb6aj}P
} #$(F&>pj
^{8r(1,
/** ? 6B
n&qa
* The constructor using fields ' } rUbJo
* 8D
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* @param page z65|NO6JW.
* @param content SP9_s7LL
*/ x72bufd
public Result(Page page, List content){ ' jFSv|g+0
this.page = page; '+BcPB?E
this.content = content; \H+/D &M
} 4os7tx
rmc0dm&l]
/** ^B2>lx\n
* @return Returns the content. E1:{5F5/
*/ b,YTw
publicList getContent(){ /N+*=LIK
I
return content; ]Y;EIn
} 79<{cexP
L.bR\fE
/** oDul ?%
* @return Returns the page. xg)cA C\=
*/ )sG`sET]`f
public Page getPage(){ F+Og8^!
return page; +DS_'Tmr
} epi{Ayb
*M;!{)m?
/** -~eNC^t;W
* @param content %'Ebm
* The content to set. BY"<90kBL
*/ >6 [{\uPK
public void setContent(List content){ Px&*&^Gf[b
this.content = content; [Y.3miE
} xn(lkQ6Fm
P6*IR|
/** yhQv $D,^f
* @param page b|t` )BF
* The page to set. fkWuSGi
*/ G8OLx+!0e
publicvoid setPage(Page page){ po+>83/!oq
this.page = page; ?!1K@/!
} g@YJ#S (}
} AQ 3n=Lr
!"B0z+O>
C5#3c yf*B
&AH@|$!E
r6&f I"Yg
2. 编写业务逻辑接口,并实现它(UserManager, kL,bM.;
0V
,R|Ln
UserManagerImpl) E[HXbj"
java代码: # 4_'%~-e
zbZ0BD7e
=@;uDu:Q
/*Created on 2005-7-15*/ ]N}80*Rl
package com.adt.service; g@hg u
Az[Yvu'<
import net.sf.hibernate.HibernateException; !vHUe*1a{
Q+gd|^Vc9
import org.flyware.util.page.Page; 1 *'SP6g
U)a}XRS
import com.adt.bo.Result; x|n2,3%
IZBU<1M
/** p't>'?UH|
* @author Joa |,L_d2lb
*/ !VU[=~
publicinterface UserManager { +CtsD9PA
.%;UP7g
public Result listUser(Page page)throws d:} aFP[
/10 I}3D
HibernateException; \Fj$^I>C
L,V\g^4$K
} n; ;b6s5
j_c0oclSz
~|kre:j9
'0D2e
}Wjb0V
java代码: szN`"Yi){
2,?4'0Z@R
L}lOA,EF
/*Created on 2005-7-15*/ E#X1P #$pW
package com.adt.service.impl; !mH2IjcL
CsG1HR@
import java.util.List; /PF X1hSu
$EHAHNL?Lx
import net.sf.hibernate.HibernateException; d-nqV5
JaP2Q} &B
import org.flyware.util.page.Page; x0B|CO
import org.flyware.util.page.PageUtil; ;o }pRC
@SeE,<
import com.adt.bo.Result; j4Ppn
import com.adt.dao.UserDAO; o^%4w>|
import com.adt.exception.ObjectNotFoundException; Q.Uyl:^PxU
import com.adt.service.UserManager; 0\#uxzdhJ
DZKVZ_q
/** O?|opD
* @author Joa 5fuOl-M0W
*/ DJP)V8]!B
publicclass UserManagerImpl implements UserManager { ~.7r
Y}%=:Yt
private UserDAO userDAO; v`evuJ\3
YqwDvJWX
/** gE'b.04Y9i
* @param userDAO The userDAO to set. .w2X24Mmb
*/ _!6~o>
publicvoid setUserDAO(UserDAO userDAO){ k ]C+/
this.userDAO = userDAO; V}(snG,
} pH5"g"e1
vk:@rOpl
/* (non-Javadoc) rCqcl
* @see com.adt.service.UserManager#listUser Cp(,+dD
=o]V!MW
(org.flyware.util.page.Page) fM,U|
*/ \hv1"WaJ
public Result listUser(Page page)throws 7c$;-O
v[WbQ5AND
HibernateException, ObjectNotFoundException { )$V}tr!
int totalRecords = userDAO.getUserCount(); \
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if(totalRecords == 0) Ag
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throw new ObjectNotFoundException sI4Ql0[
8" l9W=
("userNotExist"); ]etLobV
page = PageUtil.createPage(page, totalRecords); v`#T)5gl-
List users = userDAO.getUserByPage(page); z 3)pvX5
returnnew Result(page, users); ?zp@HSa9
} f@lRa>Z(Fm
u! `oKe;
} %cJ]Ds%V
@q2If{Tk
] >-#T
%tiFx:F+
HI6;=~[
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Q|Uq.UjY
Q| >
\{M
询,接下来编写UserDAO的代码: Wo=Q7~
3. UserDAO 和 UserDAOImpl: Rr+Y::E
java代码: KY$6=/?U_
fOtin[|}6@
~_=ohb{
/*Created on 2005-7-15*/ "P;_-i9O
package com.adt.dao; KIO{6
-:wC920+
import java.util.List; P<yd
kr2V
import org.flyware.util.page.Page; |u,2A1
7Fb |~In<Z
import net.sf.hibernate.HibernateException; tn};[r
K|
#%u2C
/** -~T? xs0_
* @author Joa fbp6lE
*/ Av[L,4A
publicinterface UserDAO extends BaseDAO { 4{H>V_9zs
&A>Hq/Y
publicList getUserByName(String name)throws Y0iL+=[k`m
UV8,SSDTV
HibernateException; l9
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f;M7y:A8q,
publicint getUserCount()throws HibernateException; m5Gt8Z 6a
#UGm/4C
publicList getUserByPage(Page page)throws RkP g&R;i
v
WKUV|
HibernateException; tj@IrwC^e"
5at\!17TY
} ;i|V++$_
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TGx:#x*k
|pk1pV |
D(6d#c
java代码: ]l.y/pRP5[
GGHe{l
n)$T
zND
/*Created on 2005-7-15*/ ) 9h5a+Z
package com.adt.dao.impl; KZ^W@*`D
'#d`K.;_b.
import java.util.List; T.nY>Q8
{X$8yy2zC5
import org.flyware.util.page.Page; 16=tHo8|
Z"rrbN1
import net.sf.hibernate.HibernateException; j<w";I&Diz
import net.sf.hibernate.Query; Xi3:Ok6FZ
Ht#5;c2/
import com.adt.dao.UserDAO; En%PIkxeR
]h8[b9$<")
/** @Q~Oc_z
* @author Joa b}63?.M{
*/ xJ H]>#XJ
public class UserDAOImpl extends BaseDAOHibernateImpl ><9E^ k0.
Et{4*+A
implements UserDAO { D h y
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+
/* (non-Javadoc) L ;5uB2
* @see com.adt.dao.UserDAO#getUserByName R /J@XP
F.ml]k&(m
(java.lang.String) n]G!@-z
*/ ;QbMVY
publicList getUserByName(String name)throws h; 105$E1
bp Q/#\Z
HibernateException { V~p/P
String querySentence = "FROM user in class |~vo
1?s]nU
com.adt.po.User WHERE user.name=:name"; Sgp$B:
Query query = getSession().createQuery lN"%~n?
)z#
(querySentence); qTFktJZw
query.setParameter("name", name); G/ToiUY
return query.list(); ??Zh$^No:
} Z>1\|j
f,{O%*PUA
/* (non-Javadoc) h ,;f6
* @see com.adt.dao.UserDAO#getUserCount() ?h)Z ;,}
*/ v:0.
publicint getUserCount()throws HibernateException { ~_^#/BnAl
int count = 0; B;.]<k'3
String querySentence = "SELECT count(*) FROM `0a=A#]1o
/Zs;dam
user in class com.adt.po.User"; 1s5FjD?M
Query query = getSession().createQuery lJHV c"*/
^b)8l
(querySentence); hd*bPj;
count = ((Integer)query.iterate().next Cisv**9
$oKT-G
()).intValue(); <RzGxhT
return count; b
z3&
} `BA wef
63R?=u@
/* (non-Javadoc) F&?&8.
* @see com.adt.dao.UserDAO#getUserByPage fW^\G2Fk
/7Z5_q_
(org.flyware.util.page.Page) }S84^2J_
*/ 04{*iS95J
publicList getUserByPage(Page page)throws p&'oJy.P
e@[9WnxYe
HibernateException { &qfnCM0Y
String querySentence = "FROM user in class *3 .+19Q
gaeMcL_^a
com.adt.po.User"; 8!87p?Mz
Query query = getSession().createQuery R_iQLBrd
f4F13n_0X
(querySentence); Z6@W)Q X
query.setFirstResult(page.getBeginIndex()) 'r_{T=
.setMaxResults(page.getEveryPage()); O/EI8Qvm
return query.list(); IK~'ke
} !bEy~.
a(>oQG8F
} -90qG"@
0N02 E
D|`O8o?)
!Yuu~|
Ubtu?wRBW
至此,一个完整的分页程序完成。前台的只需要调用 n^Co
uA#uq^3
userManager.listUser(page)即可得到一个Page对象和结果集对象 :ryyo$
3q7Z?1'o
的综合体,而传入的参数page对象则可以由前台传入,如果用 ]z5`!e)L
Lo"w,p`n@
webwork,甚至可以直接在配置文件中指定。 AWkXWl}
dN'2;X
下面给出一个webwork调用示例: U/2]ACGCN^
java代码: *fs'%"w-
""-#b^DQ
@2H"8KX
/*Created on 2005-6-17*/ $Pw@EC]
package com.adt.action.user; t
As@0`x9
J,@SSmJ`
import java.util.List; "[W${q+0x
s^:8bFn9$
import org.apache.commons.logging.Log; vU5a`0mH
import org.apache.commons.logging.LogFactory; vFuf{ @P
import org.flyware.util.page.Page; Z)=S. )
')!+>b(P
import com.adt.bo.Result; F$[1KjS
import com.adt.service.UserService; j*2Q{ik>J
import com.opensymphony.xwork.Action; pO^gooV\
b|7c]l
/** ~loJYq'y
* @author Joa 5\hJ&
*/ JIeKp7;^
publicclass ListUser implementsAction{ >,JLYz|</
01bBZWX
privatestaticfinal Log logger = LogFactory.getLog uCX+Lw+As
Skm$:`u;
(ListUser.class); V5$J
<HReh>)[
private UserService userService; jSLC L'
y*i_Ec\h
private Page page; %Ot2bhK;
IB~`Ht8
b
privateList users; uL`6}0
>eF4YZ"
/* \1k(4MWd
* (non-Javadoc) v]`}T/n
* tG1,AkyZ
* @see com.opensymphony.xwork.Action#execute() r?^[o
*/ N!O.=>8<
publicString execute()throwsException{ H"~]|@g-p
Result result = userService.listUser(page); EbTjBq
page = result.getPage(); y^utMH
users = result.getContent(); XQI.z7F
return SUCCESS; lHg&|S&J
} H)#HK!F6f
1Q$ePo
/** TQ-V61<5
* @return Returns the page. \?n4d#=$o
*/ -Fi{[%&u
public Page getPage(){ n%N|?!rB
return page; tCkKJ)m
} vn5X]U"
w QV4[
/** <>!Y[Xr^
* @return Returns the users. ']'H8Y-M
*/ }o>6 y>=
publicList getUsers(){ F_KPhe$
return users;
kzZdYiC
} N*d
)<8_
D%PrwfR
/** +f#oij
* @param page =P* YwLb
* The page to set. bf~gWzA
*/ m(~5X0
publicvoid setPage(Page page){ \W"N{N
this.page = page; qs$%/
} < 0S+[7S"
F%Te0l
/** hXxgKi%
* @param users q]1HCWde
* The users to set. /jBjqE;_
*/ wI\
n%#
publicvoid setUsers(List users){ YX||\
this.users = users; nveHLHvC7
} .=y-T=}
e1*<9&S
/** o6{[7jI
* @param userService SZGeF;N
* The userService to set. D{b*,F:&@)
*/ N$Pi4
publicvoid setUserService(UserService userService){ ?kOtK
this.userService = userService; B.zRDB}i=
} >Ln/ )j
} ?]JTrv"zp
[^iQE
6\8
lx|w
P)hZFX
FlWgTn>
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, z(-j%?
AOh\%|}
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 v0~'`*|&
wUnz D)
么只需要: SONv]));
java代码: \ C^fi}/]
n|G x29E
Y}G 9(Ci&
<?xml version="1.0"?> ]p,svevo
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ".n,R"EF
UODbT&&
1.0//EN" "http://www.opensymphony.com/xwork/xwork- fpCkT [&m
}Mh@%2$
1.0.dtd"> O<A$,<6 7
%/b3G*$W
<xwork> _;o)MTw|'
ccLTA
<package name="user" extends="webwork- O$'BJKj-4
?*2DR:o>@
interceptors"> v' x)AbbC
5"x=kp>!d
<!-- The default interceptor stack name _$wXHONt
<=]wh|D
--> 0nz=whS{
<default-interceptor-ref U"Gg
,
HnDz4eD
name="myDefaultWebStack"/> i_ha^mq3
4# pn]
<action name="listUser" wi7a_^{
3^ct;gz
class="com.adt.action.user.ListUser"> %kod31X3<
<param xJ/<G$LNJ0
5PaOa8=2f
name="page.everyPage">10</param> `y1nex-0
<result jFa{h!
'<Nhq_u{
name="success">/user/user_list.jsp</result> TFIP>$*_C
</action> (?9 @nS
})I_@\q
</package> Z6.0X{6nA
.?16w`Y
</xwork> sj"zgE)
C\~!2cy
=5a|'O
V^n?0^o
0^5*@vt
75u5zD
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 4Nz@s^9
-?m"+mUP
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。 [Pn(d[$z
-i,=sZXB
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Dy_ayxm
.3yoDab
/|
nZ)?
b7]MpL
0j=xWC
我写的一个用于分页的类,用了泛型了,hoho <{t*yMr
OKXELP
java代码: ?9Lp@k~TO
P^wDt14>
gpIq4Q<
package com.intokr.util; ^)qOILn
5_|Sm=
import java.util.List; XZ|%9#6
*wSz2o),
/** \yQs[l%J
* 用于分页的类<br> ~9[^abz
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ?+Q?K30:
* =vd9mb-
* @version 0.01 B+8lp4V9%
* @author cheng K\bA[5+N
*/ ,Pq@{i#
public class Paginator<E> { 6~:eO(pK
l
privateint count = 0; // 总记录数 i!|OFU6
privateint p = 1; // 页编号 BZ '63
privateint num = 20; // 每页的记录数 xI'sprNa_1
privateList<E> results = null; // 结果 Hp#IOsP~
GN&-`E]-
/** ~d9R:t1
* 结果总数 |8DMj s()*
*/ u\&F`esQ2
publicint getCount(){ ;ui=7[Us
return count; }K
rQPg
} ,Q7W))j
5a0&LNm
publicvoid setCount(int count){ KOYU'hw
this.count = count; p3Ey[kURp
} >Y3ZK{b
&8w
MGahp
/** j'2:z#
* 本结果所在的页码,从1开始 s-S#qGZ
* bhqV2y*'
* @return Returns the pageNo. a 8(mU%
*/ +NM`y=@@
publicint getP(){ 3Z taj^v
return p; )2&U
Rt.
} +\Zr\fOe|%
4s <|8
/** p7Q}xx
* if(p<=0) p=1 qm!&(8NfK
* ?y1G,0,
* @param p ZQ MK1
*/ p+ki1!Ed
publicvoid setP(int p){ .huk>
if(p <= 0) @xqjAcfg
p = 1; a7Xa3 vlpO
this.p = p; (**k4c,
} oP%'8%tk
eHIsTL@Fp
/** <k c9KE
* 每页记录数量 +nOa&d\
*/ bb@3%r|_<
publicint getNum(){ [k<w'n*
return num; 4ayZ.`aK
} )<>1Q{j@
EN\
uX!
/** (mR;MC
* if(num<1) num=1 v
7g?
*/ DJ]GM|?
publicvoid setNum(int num){ 5N5Deb#V
if(num < 1) #rps2nf.j
num = 1; v}>5!*
this.num = num; 0v"h/
} JKJ+RkXf3
]"T1clZKd(
/** u A=x~-I
* 获得总页数 MlVVST
*/ u?a4v \
publicint getPageNum(){ P c'0.4
return(count - 1) / num + 1; :JI&ngWK
} ]ssX,1#Xh
5Mb5t;4b
/** *~b}]M700
* 获得本页的开始编号,为 (p-1)*num+1 xnp5XhU
*/ $bho]~
publicint getStart(){ "m'roU
return(p - 1) * num + 1; &%infPI'
} sf(2~BMQI
U6sPJc<
/** bS2)L4MQY
* @return Returns the results. $I$ B8
*/ V=+wsc
publicList<E> getResults(){ k%-S7iQ
return results; )e|n7|} $
} )LRso>iOO
:tTP3t5
public void setResults(List<E> results){ e5HHsR6
this.results = results; 9Z_!}eY2mc
} j56Dt_
8
FJ>W.
public String toString(){ m0$~O5|4
StringBuilder buff = new StringBuilder q>^x,:L
l`M7a9*U
(); G*].g['
buff.append("{"); ,|Xibfw
buff.append("count:").append(count); {
d*?O
buff.append(",p:").append(p); cCWk^lF],
buff.append(",nump:").append(num); ~A-1x!YiU
buff.append(",results:").append M<KWx'uV
aplOo[
(results); :TTZ@ q
buff.append("}"); u@ psVt
return buff.toString(); s${|A=
} ,!{/Y7PmJ
$ Lf-Gi
} rT}k[
@x4IxGlUs
Obl,Qa:5