Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ~(`iR xK
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 pJ5Sxgv{;
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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 K(HP PM\
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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 [?hc.COE
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分页支持类: 3l 0>
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java代码: ;HJ|)PN5L
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package com.javaeye.common.util; T!)v9L
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import java.util.List; eJ#q! <
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publicclass PaginationSupport { LQs2!]?HT
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publicfinalstaticint PAGESIZE = 30; i9oi}$;J
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privateint pageSize = PAGESIZE; &la;Vu"dp
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privateList items; m$:o+IH/
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privateint totalCount; xS`>[8?3<T
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privateint[] indexes = newint[0]; kfBVF%90
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privateint startIndex = 0; -[4Xg!apO
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public PaginationSupport(List items, int _{6QvD3kg.
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totalCount){ r"a0!]n
setPageSize(PAGESIZE); gYx|Na,+
setTotalCount(totalCount); YzSUJ=0/
setItems(items); 8|w_PP1oE
setStartIndex(0); iP;X8'< BC
} 0zaE?dA]
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public PaginationSupport(List items, int =$IjN v(?
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totalCount, int startIndex){ -Vk+zEht
setPageSize(PAGESIZE); nqt;Ge
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setTotalCount(totalCount); &V[m{.
setItems(items); q7C>A`w
setStartIndex(startIndex); XU .FLNe
}
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public PaginationSupport(List items, int !~cTe!T
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totalCount, int pageSize, int startIndex){ DGTSk9iK(
setPageSize(pageSize); 1_!*R]a q
setTotalCount(totalCount); :~pPB#)nk
setItems(items); pUWj,&t
setStartIndex(startIndex); Zycu3%JI
} SqTO~zGC
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publicList getItems(){ Y6/'gg'&5
return items; S\
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} TDdFuO'}
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publicvoid setItems(List items){ }\B`tAN
this.items = items; hV/$6 8A_
} 7^h?<X\
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publicint getPageSize(){ "*WzoRA={
return pageSize; =m=`| Bn
} !12W(4S5
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publicvoid setPageSize(int pageSize){ 2Tt@2h_L
this.pageSize = pageSize; Bhl@\Kq
} Ft>Abj,6
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publicint getTotalCount(){ `itaQGLD
return totalCount; oW(p (>
} ~fn2B
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publicvoid setTotalCount(int totalCount){ T%Vii*?M
if(totalCount > 0){ #vYdP#nWb
this.totalCount = totalCount; Nrva?W_i
int count = totalCount / Iw8;",e2
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pageSize; a5:Q%F<!
if(totalCount % pageSize > 0)
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count++; ? r=cLC
indexes = newint[count]; )R+@vh#Q<$
for(int i = 0; i < count; i++){ H?8KTl=e
indexes = pageSize * JNRG[j
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i; ]QM6d(zDA
} )Fk%,H-1
}else{ `9Zoq=/
this.totalCount = 0; .0S.7w3dZo
} b40zYH`'{
} 5 @bLDP
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publicint[] getIndexes(){
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return indexes; ' D+h_*H
} d>eVR
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publicvoid setIndexes(int[] indexes){ "d>{hP
this.indexes = indexes; F_U3+J >
} `UL#g![J
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publicint getStartIndex(){ F`3c uL[N
return startIndex; dX: (%_Mn
} at${^,&
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publicvoid setStartIndex(int startIndex){ meT~b
if(totalCount <= 0) C] qY
this.startIndex = 0; 2f16 /0J@
elseif(startIndex >= totalCount) 7^#f<m;Ar!
this.startIndex = indexes eyy{z;D8r
~mx me6"v
[indexes.length - 1]; MbC7`Sp&i
elseif(startIndex < 0) Xy:'f".M~\
this.startIndex = 0; k:Sxs+)?1
else{ (m4`l_
this.startIndex = indexes 2Otd
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[startIndex / pageSize]; sH(4.36+
} r.0IC*Y
} Q\ TawRK8
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publicint getNextIndex(){ 3 :X3n\z
int nextIndex = getStartIndex() + m+||t
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pageSize; )uiYu3 I
if(nextIndex >= totalCount) Lnbbv
*
return getStartIndex(); fDhV
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else U0q{8 "Pl
return nextIndex; LCx{7bN1ro
} @*e|{;X]hy
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publicint getPreviousIndex(){ 3t5`,R1@t
int previousIndex = getStartIndex() - u;p{&\(]
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pageSize; [URo#
if(previousIndex < 0) hC?:XVt
return0; $As;Tvw.
else @|v4B[/
return previousIndex; <61T)7
} Vrzx;V%
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} n~l9`4wJY
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抽象业务类 zD:"O4ZM^^
java代码: O-y/K2MC*
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/** %yX?4T;b
* Created on 2005-7-12 'd 4I/
*/ S.1\e"MfI
package com.javaeye.common.business; 5A
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import java.io.Serializable; c""*Ng*T
import java.util.List; N7:=%F y(
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import org.hibernate.Criteria; @^]wT_r
import org.hibernate.HibernateException; 9J h"1i>x2
import org.hibernate.Session; A5cx!h
import org.hibernate.criterion.DetachedCriteria; NFw7g&1;Kp
import org.hibernate.criterion.Projections; m/RX~,T*v&
import a~E@scD
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org.springframework.orm.hibernate3.HibernateCallback; NC'+-P'y
import 'NHtCs=F
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org.springframework.orm.hibernate3.support.HibernateDaoS IV*@}~BJ
nf=*KS\v
upport; a3D''Ra
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import com.javaeye.common.util.PaginationSupport; P,U$
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public abstract class AbstractManager extends BH6)`0&2*N
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HibernateDaoSupport { IZ+kw.6e
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privateboolean cacheQueries = false; BK`NPC$a
@v{lH&K:;
privateString queryCacheRegion; TP7'tb
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publicvoid setCacheQueries(boolean ATx6YP@7~
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cacheQueries){ &AM<H}>
this.cacheQueries = cacheQueries; 7R9.g6j
} qNb|6/DG
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publicvoid setQueryCacheRegion(String +@*}_%^l"
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queryCacheRegion){ D+edTAQ8
this.queryCacheRegion = YuufgPE*H
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queryCacheRegion; rP$vZ^/c
} RO.GD$ 3n
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publicvoid save(finalObject entity){ Axp#8
getHibernateTemplate().save(entity); b{Srd3
} .x\fPjB
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publicvoid persist(finalObject entity){ dQP7CP
getHibernateTemplate().save(entity); }?[^q
} 74f3a|vx/
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publicvoid update(finalObject entity){ Pf,S`Uw;
getHibernateTemplate().update(entity); s&(,_34
} &%J+d"n(
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publicvoid delete(finalObject entity){ ,K4*0!TXP
getHibernateTemplate().delete(entity); `"~s<+
} )D_ZZPq_
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publicObject load(finalClass entity, WOqAVd\
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finalSerializable id){ HqM>K*XKU
return getHibernateTemplate().load ~yacJU=
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(entity, id); BC!n;IAe
} Twqkd8[
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publicObject get(finalClass entity, Qdepzo>E
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finalSerializable id){ 5vxKkk&i4l
return getHibernateTemplate().get !%w#h0(b
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(entity, id); <eWGvIEP[
} $xx5+A%,
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publicList findAll(finalClass entity){ >R|*FYam
return getHibernateTemplate().find("from /JP]5M)
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" + entity.getName()); WY=RJe2
} _PTo!aJL
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publicList findByNamedQuery(finalString 31BN ?q
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namedQuery){ HbQvu@
return getHibernateTemplate #Bo/1G=
P<+y%g(({
().findByNamedQuery(namedQuery); m3|KIUP
} %y@iA91K
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publicList findByNamedQuery(finalString query, 44s
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finalObject parameter){ bXN-q!
return getHibernateTemplate &5*)r@+
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().findByNamedQuery(query, parameter); y&y(<
} 5fh@nR
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publicList findByNamedQuery(finalString query, ZqI.n4:9
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finalObject[] parameters){ >{DHW1kF?
return getHibernateTemplate .3;bUJ1
@G/':N
().findByNamedQuery(query, parameters); R=D\VIu,Z
} 'WqSHb7
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publicList find(finalString query){ xP@VK!sc
return getHibernateTemplate().find !;Mh5*-
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(query); 8ad!.
} dhW; |
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publicList find(finalString query, finalObject 1'|6IR1'
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parameter){ f;/t7=>d
return getHibernateTemplate().find *
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(query, parameter); !g? ~<`
} -Q@jL{Ue
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public PaginationSupport findPageByCriteria Y^)VHE]
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(final DetachedCriteria detachedCriteria){ ivdw1g|)h
return findPageByCriteria y$)gj4k/D
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Isq3YY
} 9Ao0$|@b
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public PaginationSupport findPageByCriteria ^qpa[6D6x
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(final DetachedCriteria detachedCriteria, finalint .js4)$W^
-;$+`<%
startIndex){ UQ|zSalv,
return findPageByCriteria F"a^`E&
@LY 5]og
(detachedCriteria, PaginationSupport.PAGESIZE, R|Ft@]
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startIndex); `w Sg/
} Q, E!Ew3
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public PaginationSupport findPageByCriteria K{VF_S:
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(final DetachedCriteria detachedCriteria, finalint H+zn:j@~L
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pageSize, PMZdz>>T
finalint startIndex){ VGcl)fIqw?
return(PaginationSupport) V,qZF=} S
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getHibernateTemplate().execute(new HibernateCallback(){ Y51XpcXQ
publicObject doInHibernate V>P\yr?
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(Session session)throws HibernateException { Ja-D}|;
Criteria criteria = DT&[W<oN
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detachedCriteria.getExecutableCriteria(session); tYfhKJzGC
int totalCount = k?Jzy
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((Integer) criteria.setProjection(Projections.rowCount -b@E@uAX/
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()).uniqueResult()).intValue(); ;hs:wLVa"
criteria.setProjection 6\86E$f=h
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(null); PqcuSb6
List items = BN4dr9T
)<.S3
criteria.setFirstResult(startIndex).setMaxResults pb%#`2"
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(pageSize).list(); 9BANCW"
PaginationSupport ps = HkvCQ H
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new PaginationSupport(items, totalCount, pageSize, ^OG^%
x"
@n(=#Q3
startIndex); >1ZMQgCG
return ps; cXJgdBwo
} jn\\,n"6
}, true); JXj`
} ^
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public List findAllByCriteria(final ?p5RSt
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DetachedCriteria detachedCriteria){ fJv0 B*
return(List) getHibernateTemplate %8o(x 0
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().execute(new HibernateCallback(){ C>68$wd>
publicObject doInHibernate Op3 IL/
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(Session session)throws HibernateException { |0f\>X I
Criteria criteria = qw87B!D
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detachedCriteria.getExecutableCriteria(session); s*k"-5
return criteria.list(); \g4\a?i
} &s/aJgJhp
}, true); ?5mVC]W?]
} =X&h5;x'
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public int getCountByCriteria(final #<'/sqL
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DetachedCriteria detachedCriteria){ :o}7C%Q8
Integer count = (Integer) `ss]\46>
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getHibernateTemplate().execute(new HibernateCallback(){ (f#W:]o/
publicObject doInHibernate LO"HwN43h
c<&+[{|
(Session session)throws HibernateException { !.t'3~dUf$
Criteria criteria = !hH6!G
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detachedCriteria.getExecutableCriteria(session); 0^ (.(:
return U}A+jJ
q=?"0i&V
criteria.setProjection(Projections.rowCount 6C]!>i}U
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()).uniqueResult(); OD1ns
} r)j#Skh].
}, true); R:.7c(s
return count.intValue(); ^\+6*YE 4
} hChM hc
} ;
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用户在web层构造查询条件detachedCriteria,和可选的 G~esSL^G/
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 Wiu"k%Qsh
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PaginationSupport的实例ps。 6i~WcAs
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ps.getItems()得到已分页好的结果集 |H+Wed|
ps.getIndexes()得到分页索引的数组 U ZsH9
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ps.getTotalCount()得到总结果数 E+w<RNBmz
ps.getStartIndex()当前分页索引 Y.r+wc]
ps.getNextIndex()下一页索引 `$C
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ps.getPreviousIndex()上一页索引 8pgEix/M5o
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 N'`A?&2ru
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 A$:U'ZG_
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一下代码重构了。 q#=(e:aCb
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我把原本我的做法也提供出来供大家讨论吧: J~UuS+Ufv
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首先,为了实现分页查询,我封装了一个Page类: 7VF LJrt
java代码:
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/*Created on 2005-4-14*/ OH(waKq2I
package org.flyware.util.page; +&2%+[nBZ
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/** b`O'1r\Y;
* @author Joa DZPPJ2 }
* r?
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*/ Da&]y
publicclass Page { 8q}q{8
V /V9B2.$
/** imply if the page has previous page */ UQ@L V~6{R
privateboolean hasPrePage; ?oHpFlj
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/** imply if the page has next page */ <3C*Z"aQ>|
privateboolean hasNextPage; -I,$_
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/** the number of every page */ 'u |c
privateint everyPage; `,TzQ
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/** the total page number */ @'!SN\?W8
privateint totalPage; <T|3`#o0
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/** the number of current page */ Q| ?L*Pq2I
privateint currentPage; 76h ,]xi
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/** the begin index of the records by the current zsyIV!(
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query */ (\YltC@q%
privateint beginIndex; 6.nCV0xA
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/** The default constructor */ +Kbjzh3<wG
public Page(){ O*)Vhw'pK
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} ]*[ 2$
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/** construct the page by everyPage &H/'rd0M
* @param everyPage D (?DW}Rqs
* */ iN8zo:&Z
public Page(int everyPage){ lBvR+9Qw
this.everyPage = everyPage; xH"/1g
} "8jf81V*
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/** The whole constructor */ A1>OY^p3%
public Page(boolean hasPrePage, boolean hasNextPage, 70tH:Z)"
*@=/qkaJaI
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int everyPage, int totalPage, l$pm_%@2]
int currentPage, int beginIndex){ Jgd'1'FOs
this.hasPrePage = hasPrePage; e_ANUll1
this.hasNextPage = hasNextPage; 8_B4?` k
this.everyPage = everyPage; ;dZZ;#k%
this.totalPage = totalPage; T{ XS")Vw
this.currentPage = currentPage; 9u}Hmb
this.beginIndex = beginIndex; s/ qYa])
} hxd`OG<gF
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/** ;m{1_ 1
* @return BdblLUGK#
* Returns the beginIndex. cZU=o\
*/ k(7&N0V%zz
publicint getBeginIndex(){ lKp"xcAD
return beginIndex; ']z{{UNUN
} YdC6k?tzS
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/** 4`]^@"{
* @param beginIndex ]i ,{
* The beginIndex to set. D_^
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*/ VfC <WVYiZ
publicvoid setBeginIndex(int beginIndex){ &zeyE;/Hj
this.beginIndex = beginIndex; ][h%UrV
} ]]9R mh=
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/** {xB!EQ"
* @return s.N/2F&*W
* Returns the currentPage. Pz |>"'
*/ q{I%Q)t)gU
publicint getCurrentPage(){ 1
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return currentPage; Ed,~1GanY
} {19PL8B~}
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/** sRL`dEl4l
* @param currentPage >xYpNtEs
* The currentPage to set. 9gEwh<
*/ C>j@,G4
publicvoid setCurrentPage(int currentPage){ ]kRfB:4ED
this.currentPage = currentPage; "ZoRZ'i
} z] PSpUd
>j(_[z|v3
/** E}Z/*lX
* @return BsqP?/
* Returns the everyPage. ,nLy4T&"
*/ q#ClnG*
publicint getEveryPage(){ Ou!2[oe@M
return everyPage; X0H!/SlS
} {V$|3m>:*
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/** O%zU-_|*
* @param everyPage Cc' 37~6~P
* The everyPage to set. 8 \ +T8(m
*/ R_ ,U Mt
publicvoid setEveryPage(int everyPage){ Ug t.&IA
this.everyPage = everyPage; K'Tm_"[u
} ," Wr"
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/** >WQMqQ^t@
* @return Mxsa-?R;v
* Returns the hasNextPage. k,E{C{^M
*/ EZy)A$|
publicboolean getHasNextPage(){ \fyRsa)
return hasNextPage; N~d ?WD\^
} ceh j;
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/** \y)rt )
* @param hasNextPage { MSkHf=
* The hasNextPage to set. |\<`Ib4j
*/ ~'iHo]9O
publicvoid setHasNextPage(boolean hasNextPage){ '()xHEGl3
this.hasNextPage = hasNextPage; }=UHbU.n~!
} ?'Xj
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/** $@Rxrx_@M
* @return #ASz;$P
* Returns the hasPrePage. U;V7 u/{
*/ 9T}pT{~V
publicboolean getHasPrePage(){ 4(~L#}:r!
return hasPrePage; 8'.Hyy@;
} ?'#`
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/** `H_ 3Uc
* @param hasPrePage $L>@Ed<
* The hasPrePage to set. pV
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*/ +0%w ;'9z
publicvoid setHasPrePage(boolean hasPrePage){ HU}7zK2
this.hasPrePage = hasPrePage; _ Yx]_Y9I
} YTX,cj#D^&
i]y<|W)Q3
/** `* ["UER
* @return Returns the totalPage. k\YG^I
* a|x.C6Pe
*/ *_{j=sd
publicint getTotalPage(){ [vK^Um
return totalPage; |zNX=mAV
} u\x}8pn
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/** Ic:(Gi- %
* @param totalPage ,I$`-$_'
* The totalPage to set. }DEg-j,F
*/ B5VKs,g
publicvoid setTotalPage(int totalPage){ ygS;$2m%2
this.totalPage = totalPage; y$F'(b|)
} AGO+p(6d=g
<#y[gTJ<'>
} yZ(zdM\/sL
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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 VimE@ Hz
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个PageUtil,负责对Page对象进行构造: qu6D 5t
java代码: 7qLpZ/
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/*Created on 2005-4-14*/ ks qQM
package org.flyware.util.page; `$<.pOm
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import org.apache.commons.logging.Log; 7Lc]HSZo,
import org.apache.commons.logging.LogFactory; )?naN
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/** A5RN5`}
* @author Joa
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* qI9z;_,gNz
*/ K5VWt)Z#
publicclass PageUtil { |t&>5HM
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privatestaticfinal Log logger = LogFactory.getLog K.nHii
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(PageUtil.class); 8f4b&ah
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/** m@F`!qY~Y\
* Use the origin page to create a new page ~&_z2|UXp
* @param page T_
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* @param totalRecords d-ZJL6-
* @return @|m/djN5x
*/ oUr66a/[U
publicstatic Page createPage(Page page, int f4b/NG|
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totalRecords){ Y;Dp3v!
return createPage(page.getEveryPage(), m%?pf2%I#
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page.getCurrentPage(), totalRecords); Jbg/0|1
} J26V nK
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/**
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* the basic page utils not including exception 9Cp-qA%t
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handler S-b/S5
* @param everyPage EIAc@$4
* @param currentPage 8)3*6+D
* @param totalRecords Rz/gtEP
* @return page P [ck84F/
*/ *?>T,gx}
publicstatic Page createPage(int everyPage, int E \EsWb
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currentPage, int totalRecords){ TnA-;Ha
everyPage = getEveryPage(everyPage); J#(LlCs?@c
currentPage = getCurrentPage(currentPage); D&
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int beginIndex = getBeginIndex(everyPage, }W8;=$jr
e4_rC'=
currentPage); c )g\/
int totalPage = getTotalPage(everyPage, RnE4<Cy
w<3#1/g!2B
totalRecords); >J?fl8
boolean hasNextPage = hasNextPage(currentPage, o4,6.1}
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totalPage); /NFj(+&g+
boolean hasPrePage = hasPrePage(currentPage); Fb>?1i`RN
1{.|+S Z!
returnnew Page(hasPrePage, hasNextPage, `?@}>.
everyPage, totalPage, !zpRrx_
currentPage, k FD;i
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beginIndex); 'ya{9EdlT
} yYYSeH
^*Q ?]N
privatestaticint getEveryPage(int everyPage){ 7"x;~X
return everyPage == 0 ? 10 : everyPage; g%I"U>!2
} xml7Uarc
KqJs?Won
privatestaticint getCurrentPage(int currentPage){ h"Q8b}$^)
return currentPage == 0 ? 1 : currentPage; !hy-L_wL]
} zxl@(hd
UnV.~ u~
privatestaticint getBeginIndex(int everyPage, int ,PW'#U:
<2x^slx)?
currentPage){ i$#;Kpb`^
return(currentPage - 1) * everyPage; O+]ZyHnB
} R|, g<
KYI/
privatestaticint getTotalPage(int everyPage, int U_Ptqqt%
-f^tE,-
totalRecords){ %OCb:s
int totalPage = 0; j2[+ztG
tw/dD +
if(totalRecords % everyPage == 0) /Iokf@5
totalPage = totalRecords / everyPage; o#Dk&
cH
else ()?(I?II
totalPage = totalRecords / everyPage + 1 ; `UaD6Mc<Mz
+ GN(Ug'R
return totalPage; `HSKQ52
} _ <V)-Y
F~W6Bp^W
privatestaticboolean hasPrePage(int currentPage){ ueWEc^_>
return currentPage == 1 ? false : true; 3(N$nsi
} .!3|&V'<
P3=G1=47U
privatestaticboolean hasNextPage(int currentPage, RSRS wkC
3jU&zw9
int totalPage){ \?-<4Bc@
return currentPage == totalPage || totalPage == Hzz %3}E
yx[/|nZDC4
0 ? false : true; '<)n8{3Q5w
} eC4[AX6e
8kIksy
2@],ZLa
} rZ$O?K
Of#u
+TL%-On
pah'>dAL
b_taC^-l
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。 |>^JRx
Dml;#'IF3
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 _;y9$"A
Dx?,=~W9
做法如下: LonxT&"!D
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 RbnVL$c
,[KD,)3y
的信息,和一个结果集List: &6!)jIWJ
java代码: vh%B[brUJ
nR~@#P\
V f&zL
Sgr
/*Created on 2005-6-13*/ vA{-{Q
package com.adt.bo; F/{!tx
b8t7u
import java.util.List; Sz`,X0a
RtS+<^2a;
import org.flyware.util.page.Page; ? OM!+O
1CZgb
/** <'oQ \eB
* @author Joa PC8Q"O
*/ (ZZ8L-s
publicclass Result { >+1duAC
q3!bky\
private Page page; lUZ+YD4
.`eN8Dl1
private List content; h[Y1?ln&h
K\r8g=U
/** bAqA1y3=
* The default constructor YD6'#(
*/ (w3YvG.
public Result(){ 2/^3WY1U
super(); ES7s1O$#
} ouQ T
M6jy\<a
/** ~36!?&eA8
* The constructor using fields d7upz]K9g
* q|(HsLs
* @param page tyFzSrfc
* @param content ^nz.j
*/ n-;`Cy`k
public Result(Page page, List content){ k y7Gwc
this.page = page; wi=v}R_
this.content = content; vk^xT
} H1./x6Hr
S=5o
< 1
/** lL3U8}vn
* @return Returns the content. XRi8Gpg
*/ m:2^=l4
publicList getContent(){ NXrlk
return content; W${Ue#w77
} ^09,"<@k
&h/Xku&0
/** U5de@Y
* @return Returns the page. h2R::/2.
*/ #\m<Sz5Gp#
public Page getPage(){ onzxx4bax
return page; f+!(k)GWd
} k9!{IScq
F JyT+
/** q_58;Bv
* @param content (!WD1w
* The content to set. xb8!B
*/ `|q(h Ow2
public void setContent(List content){ ~]2K^bh8&
this.content = content; + ePS14G
} kxv1Hn"`{E
YaqJ,"GlT
/** 7kEn \
* @param page \4fQMG
* The page to set. rey!{3U
*/ =aW9L)8D
publicvoid setPage(Page page){ %.|@]!C
this.page = page; Km$\:Xo
} 9%9#_?RW
} bk[!8-b/a
NzvXN1_%
zO6oT1I
\9T7A&
K$=zi}J W
2. 编写业务逻辑接口,并实现它(UserManager, 3Y$GsN4ln
#H~64/
UserManagerImpl) ~t~|"u"P
java代码: ;2QP7PrSY
T>W,'H
]Y&VT7+Z
/*Created on 2005-7-15*/ +ZP7{%
package com.adt.service; i83OOV$1J
f/?P514h
import net.sf.hibernate.HibernateException; sYA1\YIii
BI@[\aRLQ
import org.flyware.util.page.Page; $I?"lky
>A"(KSNL
import com.adt.bo.Result; pQB."[n
%xLhZ\
/** xAm6BB
c
* @author Joa Ny/MJ#Lq
*/ $F.a><1rY
publicinterface UserManager {
[$UI8tV
t]G:L}AOl
public Result listUser(Page page)throws X:{!n({r=
@H8EWTZ
HibernateException; -KbYOb
!&E-}}<
} vl)l'
jPkn[W#
6
8z\xrY
j?QDR
J'r^/
java代码: 8u]2xB=K
F!K>K z
lyhiFkO
iH
/*Created on 2005-7-15*/ _aeBauD
package com.adt.service.impl; COlaD"Y
'J|_2*
import java.util.List; MolgwVd
6Kz,{F@
import net.sf.hibernate.HibernateException; x,'!gT:j
\~ wMfP8
import org.flyware.util.page.Page; d0>
zS
import org.flyware.util.page.PageUtil; G3v5KmT
>yDZw!C
import com.adt.bo.Result; Y_P!B^z3
import com.adt.dao.UserDAO; |y!A&d=xYn
import com.adt.exception.ObjectNotFoundException; ,/unhfs1q
import com.adt.service.UserManager; DtnEi4h,
],].zlN
/** \'j|BJ~L f
* @author Joa %&bY]w
*/ ,hmL/K0"(5
publicclass UserManagerImpl implements UserManager { &)<)^.@3G^
&%Tj/ Qx
private UserDAO userDAO; `M6)f?|$.
cB&:z)i4
/** oP.7/*p
* @param userDAO The userDAO to set. poFg1
*/ i@J;G`
publicvoid setUserDAO(UserDAO userDAO){ 9gZ$
this.userDAO = userDAO; P!k{u^$L
} )!T/3|C
Xn
;AZu^'R
/* (non-Javadoc) A+{VGP^
* @see com.adt.service.UserManager#listUser (7*}-Uy[C
/Ci<xmP
(org.flyware.util.page.Page) P0b7S'a4!
*/ $ME)#(
public Result listUser(Page page)throws IE~ |iQ?-
>LuYHr
HibernateException, ObjectNotFoundException { #_ lDss
int totalRecords = userDAO.getUserCount(); e>7i_4(C
if(totalRecords == 0) 4KrL{Z+}
throw new ObjectNotFoundException dgePPhj
T[A69O]v
("userNotExist"); Ga'swP=hf
page = PageUtil.createPage(page, totalRecords); WX0tgXl
List users = userDAO.getUserByPage(page); ?z
u8)U
returnnew Result(page, users); >o,TZc\
} "zy7C*)>r
I<tm"?q0
} 8\gjST*
v.5+7,4
)dSi/
4X|zmr:A
SX-iAS[<
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 T]p-0?=4vv
W@!S%Y9
询,接下来编写UserDAO的代码: ;9g2?-svw
3. UserDAO 和 UserDAOImpl: OZ!^ak
java代码: 4E?Oky#}-
6LZ;T.0o
S21,VpW\
/*Created on 2005-7-15*/ ^Zp>G{QL{
package com.adt.dao; dcT80sOC
j
<RrLn_
import java.util.List; {1
94!S4z
0qT%!ku&
import org.flyware.util.page.Page; Wo,?+I
29q _BR *:
import net.sf.hibernate.HibernateException; ~F7gP{r
iG?[<1~
/** C"enpc_C/
* @author Joa 3oG,E;(
*/ >yh2Lri
publicinterface UserDAO extends BaseDAO { tklH@'q
S 6,.FYH
publicList getUserByName(String name)throws B?o7e<l[
Xb,3Dvf
HibernateException; BFW&2
+d-NL?c
publicint getUserCount()throws HibernateException; yR.Ong
76` .Y
publicList getUserByPage(Page page)throws L4?IHNB
5rUdv}.
HibernateException;
.3!1` L3
@ur+;IK$
} T9q-,w/j;
aFIw=c(nP
W`*r>`krVJ
&]-DqK7
*4_Bd=5(U
java代码: s(roJbJ_;
S`?!G&[!>
9Lfv^V0
/*Created on 2005-7-15*/ 5nVt[Puw
package com.adt.dao.impl; '$QB$2~V
G9@0@2aY8
import java.util.List; @AuO`I@p=
?b5^
import org.flyware.util.page.Page; BDZ?Ez\Sg
xi;`ecqS<
import net.sf.hibernate.HibernateException; RY*U"G0#w
import net.sf.hibernate.Query; 5i{j' {_(8
EDs\,f}
import com.adt.dao.UserDAO; ,3 u}x,
O%HHYV%[m
/** ,wdD8ZT'Ip
* @author Joa 9@)O_@=
*/ ##4HYQ%E
public class UserDAOImpl extends BaseDAOHibernateImpl t<?,F
)sQ*Rd@t[8
implements UserDAO { -RK- Fu<e
uhutg,[
/* (non-Javadoc) 9k[9P;"F:
* @see com.adt.dao.UserDAO#getUserByName XHGFf_kW_N
LB?u8>a' I
(java.lang.String) ]:/Q]n^
*/ 2T[9f;jM'
publicList getUserByName(String name)throws -+-_I*(
<yg F(
HibernateException { &XUiKnNW
String querySentence = "FROM user in class tIS<U(N;
QnX(V[
com.adt.po.User WHERE user.name=:name"; *EwR!L*
Query query = getSession().createQuery 0S$N05
VTHH&$ZNq
(querySentence); s=/v';5J2!
query.setParameter("name", name); 57'4ljvYi
return query.list(); 2jCf T>`3
} 7W.~
H~z`]5CN
/* (non-Javadoc) PRE|+=w$
* @see com.adt.dao.UserDAO#getUserCount() 6Sn .I1Wy
*/ QUQ'3
publicint getUserCount()throws HibernateException { 0}dpK $.
int count = 0; #
c^z&0B}
String querySentence = "SELECT count(*) FROM WvZ8/T'x
}|5Pr(I
user in class com.adt.po.User"; c_!cv":s
Query query = getSession().createQuery l0i^uMS
dzrio-QU~
(querySentence); r^ ZEImjc
count = ((Integer)query.iterate().next D=&Me=$
K8Y=S12Ti
()).intValue(); uOdl*| T?
return count; @bP)406p
} i,9)\1R
7EO_5/cY
/* (non-Javadoc) cq4Ipe
* @see com.adt.dao.UserDAO#getUserByPage >Wg hn:^
ls)%c
(org.flyware.util.page.Page) {h`uV/5@`
*/ C'}KTXiRW
publicList getUserByPage(Page page)throws ZLAy-
9^Y
R@k&SlL'`
HibernateException { "kgdbAZ
String querySentence = "FROM user in class [QT#Yf0
TBU&6M>{3
com.adt.po.User"; I`4*+a'q&
Query query = getSession().createQuery L4y4RG/SJ:
y9}>: pj4
(querySentence); e'b(gD}
query.setFirstResult(page.getBeginIndex()) W-zP/]Dh
.setMaxResults(page.getEveryPage()); mF^v ~
return query.list(); _n>,!vH
} AbmAKA@
EG |A_m85
} e.V:)7Uc
^eYVWQ'
LTx,cP
0F><P?5
`$aZ0+
至此,一个完整的分页程序完成。前台的只需要调用 WbqWG^W
Czu\RXJR
userManager.listUser(page)即可得到一个Page对象和结果集对象 8StgsM
_/5H l`
的综合体,而传入的参数page对象则可以由前台传入,如果用 Pw!MS5=r
ChXq4]
webwork,甚至可以直接在配置文件中指定。 #"iu|D
[-oc>;`=l
下面给出一个webwork调用示例: AX/m25x
java代码: w!clI8v/
>fQN"(tf
+ k:?;ZG
/*Created on 2005-6-17*/ mYX) =B{
package com.adt.action.user; $Yc9><i
qo|iw+0Y
import java.util.List; #YdU,y=B
?sE21m?b-
import org.apache.commons.logging.Log; (#lS?+w)
import org.apache.commons.logging.LogFactory; +(0eOO'\M
import org.flyware.util.page.Page; &rKhB-18)
mD3#$E!A1
import com.adt.bo.Result; [8#l~
|U
import com.adt.service.UserService; Qg=~n:j
import com.opensymphony.xwork.Action; h08T Q=n
IuD<lMeJJ
/** 2ra4t]f6
* @author Joa hI0l2OE
*/ `Fr$q1qae{
publicclass ListUser implementsAction{ i=@*F$,
uI/
A_
privatestaticfinal Log logger = LogFactory.getLog LLiX%XOh
|n8^Xsx4w
(ListUser.class); gX<C-y6o
C? S %fF
private UserService userService; *1Q?~
GYO"1PM
private Page page; 9:s!#FYFM
?=&*6H_v
privateList users; =j-{Mxb3
3E-&8x7uYR
/* j/&7L@Y
* (non-Javadoc) 7dZ!GX?\y
* Jjv&@a}
* @see com.opensymphony.xwork.Action#execute() 8wOPpdc
*/ wC~Uy%
publicString execute()throwsException{ _45"Z}Zx
Result result = userService.listUser(page); `N+ P,
page = result.getPage(); Lq.k?!D3uh
users = result.getContent(); 1)y}.y5S
return SUCCESS; (X/JXu{
} "^`AS"z'
m{|n.b
/** !v=ha%w{
* @return Returns the page. he@swE&
*/ 3V]a "C
public Page getPage(){ |>)mYLN!y
return page; vSh)r 9
} ::6@mFL R
NG ~sE&,7
/** ,O(uuq
* @return Returns the users. +FI]0r
*/ $v,_8{ !
publicList getUsers(){ xp=
]J UQ
return users; n7vi@^lf(
} V!p;ME
R4?/7
/** ja2LXM
* @param page MeC@+@C
* The page to set. ~7|z 2L
*/ ^<c?I re
publicvoid setPage(Page page){ K2JS2Y]
this.page = page; TD'1L:mv
} oT
OMqR{"
%0 S0"t
/** v2NzPzzyb
* @param users S"*wP[d.9
* The users to set. zKo,B/Ke4
*/ 6Y=)12T
publicvoid setUsers(List users){ i{.!1i:
this.users = users; G9;WO*
} kN)P-![
8Pq|jK "
/** c;VW>&,B
* @param userService Onao'sjY
* The userService to set. +m_quQ/ys
*/ $|AxQQ%f
publicvoid setUserService(UserService userService){ h8Gp>b
this.userService = userService; w5p+Yx=q
} UWz<~Vy
} F{v+z8nW
NeYj[Q~xy
8WMC ~
+u7mw<A
8
GKX#-zsh79
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, IIzdCa{l
n=`UhC
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 EG,RlmcPp
z[th@!3
么只需要: B|tP3<
java代码: (c;$^xZK
;tO (,^
IsI\T8yfc
<?xml version="1.0"?> xGjEEBL
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [dL#0~CL$
rLVS#M#&e>
1.0//EN" "http://www.opensymphony.com/xwork/xwork- O:4.xe
opKtSF|)
1.0.dtd"> D9h\=[%e
Hly$ Wm
<xwork> Tw$la kw
m6s32??m
<package name="user" extends="webwork- uv, t(a.^
_|3n h;-m
interceptors"> N
G4wtDa
h<[ o;E
<!-- The default interceptor stack name Xcb\N
{C
[7V{4(%
--> [!"u&iu`
<default-interceptor-ref C Z|R-ky6p
KdUmetx1
name="myDefaultWebStack"/> uCx\Bt"VI
Pt E>08
<action name="listUser" R ~#\gMs
f5AK@]4G
class="com.adt.action.user.ListUser"> AkGCIn3
<param 9k1n-po
oE}1D?3Sp
name="page.everyPage">10</param> E}UlQq
<result H13|bM<
2%QY~Ku~
name="success">/user/user_list.jsp</result> u>}k+8~
</action> ^8DC
W`V
qjuX16o
</package> M%Ov6u<I8
tT'+3
</xwork> aB.`'d)V
7cH[}v`pn
%c):^;6p
]*?qaIdqu
Ao2t=vg
$5l 8V
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 VUk2pEGO.
VB\oK\F5z
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 D{~I
'~2;WF0h
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 smJ%^'x
`8EHhN;
U\P ;,o
A~u-Iv(U
-W2 !_
我写的一个用于分页的类,用了泛型了,hoho L]cZPfI6
a8''t_Dp
java代码: vk&C'&uV9@
IZ"d s=w
jU/0a=h9
package com.intokr.util; p \1-.
<rNCb;
import java.util.List; 4 QD.'+L
y]yp8Bs+
/** x pT85D
* 用于分页的类<br> #)z_TM07P
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pPUKx=d
* zrri&QDF<
* @version 0.01 d?S7E
q9`
* @author cheng 6p])2]N>p
*/ VU 9w2/cM
public class Paginator<E> {
v[\'
M
privateint count = 0; // 总记录数 wS9EC}s:Q
privateint p = 1; // 页编号 b$[O^p9x
privateint num = 20; // 每页的记录数 BNL Q]
privateList<E> results = null; // 结果 {fmSmD
q,A; d^g
/** <J!#k@LY]7
* 结果总数 "CX&2Xfe
*/ *%bQ p
publicint getCount(){ A70x+mjy^T
return count; =y.? =`"
} |p}qK
Fdi
/z9oPIJ=*
publicvoid setCount(int count){ h.(CAm%Y7
this.count = count; w-LMV>+6|
} l.Iov?e1S
|hk?'WGc`0
/** gq\ulLyOeZ
* 本结果所在的页码,从1开始 <KlG#7M>
* eX;C.[&7;8
* @return Returns the pageNo. CvS}U%
*/ Z(k7&^d
publicint getP(){ )OpB\k
return p; d ]R&mp|'
} wGr5V!
E]/` JI'%
/** &==X.2XW
* if(p<=0) p=1 hE@s~~JYd
* $)8b)Tb
* @param p gTa6%GM>
*/ Y%m^V?k
publicvoid setP(int p){ KF(N=?KO
if(p <= 0) {@ ygq-TZ
p = 1; b\&|030+
this.p = p; ?VaWOwWI
} lky{<jZ%
K=nW|^
/** mWN9/+!
* 每页记录数量
gJz~~g'
*/ I:?1(.kd2-
publicint getNum(){ 6HeZ<.d&
return num; oP vk ^H
} '@t}8J
K)"lq5nM
/** 0<(F
8
* if(num<1) num=1
p}I,!~}
*/ d)d\h`=Z
publicvoid setNum(int num){ K)=<hL
if(num < 1) M*6}# ST
num = 1; ;iEr+
this.num = num; "-bsWC
} [Tmpj9!q
`_M*2(rt
/** tgz
* 获得总页数 <Wqk5mR
*/ Cp {
j+Ia
publicint getPageNum(){ Ky(=O1Ufu
return(count - 1) / num + 1; fg}&=r
} C
0@tMB7
MhT.Zg\
/** ti%uyXfja
* 获得本页的开始编号,为 (p-1)*num+1 #ub!
*/ OZ2YflT
publicint getStart(){ 8y:c3jzP_
return(p - 1) * num + 1; 33/aYy
} g<d#zzP"T
A|Z'\D0
/** o$disJ
* @return Returns the results. CI%4!K;{
*/ uv>T8(w
publicList<E> getResults(){ n_ORD@$]
return results; p{c+ +P5
} +eT1/x0
V)Oj6nD]
public void setResults(List<E> results){ OZ,%T9vP
this.results = results; {[Sd[P
} m 3k}iIU7
WJD1U?`
public String toString(){ \r4QS
StringBuilder buff = new StringBuilder {tqLH2cO
JrZ"AId2
(); >U?U;i
buff.append("{"); rwYlg:
buff.append("count:").append(count); %UV'HcO/gp
buff.append(",p:").append(p); #I]5)XT
buff.append(",nump:").append(num); .~>Uh3S
buff.append(",results:").append X"'c2gaa_
T8*<
(results); O:K={#Xj
buff.append("}"); `VJJ"v<L
return buff.toString(); R>
r@[$z+
} =6o,{taZ.~
_@-D/g
} pz L !42
ctqXzM `
_hK83s4