Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 %FLe@.Ep{D
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 !r4B1fX
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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 kg^5D3!2{Q
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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 QG5)mIJ
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分页支持类: Nzl`mx16
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java代码: :a_MT
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package com.javaeye.common.util; @-.Tgpe@a
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import java.util.List; ~{q;
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publicclass PaginationSupport { Og?P5&C"9D
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publicfinalstaticint PAGESIZE = 30; Nl9}*3r
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privateint pageSize = PAGESIZE; U|v@v@IBA
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privateList items; "O8iO!:
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privateint totalCount; qm"AatA
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privateint[] indexes = newint[0]; '-_tF3x
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privateint startIndex = 0; GSVLZF'+
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public PaginationSupport(List items, int G@rV9
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totalCount){ rvPmd%nk-
setPageSize(PAGESIZE); Pl&x6\zL
setTotalCount(totalCount); dl+:u}9M$
setItems(items); #xt-65^
setStartIndex(0); ltOsl-OpR
} *yN#q>1
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public PaginationSupport(List items, int _A6e|(.ll
GW0e=Y=LR
totalCount, int startIndex){ K'b #}N\
setPageSize(PAGESIZE); QaSRD/,M
setTotalCount(totalCount); bH.f4-.u>)
setItems(items); fn Pej?f:
setStartIndex(startIndex); 5wbR}`8
} q=;U(,Y
#fq&yjl#A
public PaginationSupport(List items, int 6d;RtCENo
'@WS7`@-y
totalCount, int pageSize, int startIndex){ Je=k.pO1
setPageSize(pageSize); <UbLds{+Uo
setTotalCount(totalCount); h3MZLPe
setItems(items); ij02J`w:Ra
setStartIndex(startIndex); (~]0)J
} `9Q O'^)
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publicList getItems(){ D}nIF7r2N
return items; "(vm0@8><
} VIuzBmR|\
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publicvoid setItems(List items){ 'nfdOX.d
this.items = items; B }
} =A<a9@N}N
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publicint getPageSize(){ =|IY[2^
return pageSize; 4Vv$bbu+
} T:S[[#f{5
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publicvoid setPageSize(int pageSize){ b21@iW
this.pageSize = pageSize; iV.j!H7o
} 'J_6SD
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publicint getTotalCount(){ ah15,<j
return totalCount; 1U8/.x|
} 1a'0cSH
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publicvoid setTotalCount(int totalCount){ @c;:D`\p1C
if(totalCount > 0){ R&MetQ~-{
this.totalCount = totalCount; 'h `)6{
int count = totalCount / H+ 7Fw'u
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pageSize; gS.,V!#t
if(totalCount % pageSize > 0) ? ;$f"Wl
count++; MmD1@fW32#
indexes = newint[count]; rl:D>t(:.
for(int i = 0; i < count; i++){ eI=:z/pd
indexes = pageSize * (RI+4V1
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i; r%xf=};
} #>O+!IH
}else{ 6kdcFcV-]
this.totalCount = 0; 7loIjT7
} m&+V@H
} 7o$S6Y;c4
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publicint[] getIndexes(){ }PxPJ$o
return indexes; Gr!@ih^
} )m>Y[)8!
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publicvoid setIndexes(int[] indexes){ 9&'HhJm
this.indexes = indexes; {hBnEj^@
} sQ8kLS_q8
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publicint getStartIndex(){ b^WF
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return startIndex; .Tc?PmN
} Q =4~uz|
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publicvoid setStartIndex(int startIndex){ |^ J5YwCf
if(totalCount <= 0) 5 8gkE94
this.startIndex = 0; YI+o:fGC5
elseif(startIndex >= totalCount) SVqKG+{My
this.startIndex = indexes eOs 4c`
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nk
[indexes.length - 1]; y:,m(P
elseif(startIndex < 0)
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this.startIndex = 0; jl,>0MA
else{ m4RiF
this.startIndex = indexes KfV&7yi
=|_k a8{?
[startIndex / pageSize]; ,*g.?q@W2
} O*m9qF<
} d% Nx/DS)
i} ?\K>BWq
publicint getNextIndex(){ j&"GE':Y
int nextIndex = getStartIndex() + ].3@ Dk
@%rj1Gn
pageSize; +=#@1k~
if(nextIndex >= totalCount) 0hCUr]cZ,
return getStartIndex(); yIqRSqM
else 0"DS>:Ntk
return nextIndex; |!*abc\`(`
} mjJ/rx{kbw
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publicint getPreviousIndex(){ &-p!Lg&D
int previousIndex = getStartIndex() - `l+9g"q
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pageSize; \Vl)q>K_h
if(previousIndex < 0) 17yg ~
return0; ew*;mQd
else SI:Iv:>
return previousIndex; x)-n[Fu
} 8QN/D\uq
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} Q6=>*}Cm6m
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抽象业务类 :[bpMP<bz;
java代码: drh,=M\F
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/** 'Ad |*~
* Created on 2005-7-12 r,cK#!<%
*/ [G7S
package com.javaeye.common.business; XA-,
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import java.io.Serializable; hXQo>t-$
import java.util.List; |k=5`WG
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import org.hibernate.Criteria; okLheF
import org.hibernate.HibernateException; 89a`WV@}
import org.hibernate.Session; d2tJ=.DI
import org.hibernate.criterion.DetachedCriteria; 48[b1#q]
import org.hibernate.criterion.Projections; ?tf<AZ=+^L
import |eH*Q%M
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org.springframework.orm.hibernate3.HibernateCallback; xQ\S!py-
import s -),Pv|
T#D*B]oZ}
org.springframework.orm.hibernate3.support.HibernateDaoS + wF5(
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upport; N A9ss
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import com.javaeye.common.util.PaginationSupport; n/Dk~Q)
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public abstract class AbstractManager extends |5me }!C
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HibernateDaoSupport { onF?;>[
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privateboolean cacheQueries = false; Y\{&chuF
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privateString queryCacheRegion; o&Sv2"2
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publicvoid setCacheQueries(boolean :hUt7/3c
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cacheQueries){ jjJ l\Vn
this.cacheQueries = cacheQueries; SAGECK[Ix
} sr`)l& t?
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publicvoid setQueryCacheRegion(String BH^8!7dkT
* ;<>@*
queryCacheRegion){ {iq)[)n
this.queryCacheRegion = o Np4> 7Lk
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queryCacheRegion; CB>O%m[1
} DK }1T
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publicvoid save(finalObject entity){ X1\ao[t<;c
getHibernateTemplate().save(entity); $/;<~Pzi
} 1iIag}?p
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publicvoid persist(finalObject entity){ H"%SzU
getHibernateTemplate().save(entity); ~6Df~uN
} =.f<"P51k
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publicvoid update(finalObject entity){
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getHibernateTemplate().update(entity); n]J;BW&Av
} {^SHIL
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publicvoid delete(finalObject entity){ n<66 7
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getHibernateTemplate().delete(entity); cO/.(KBF
} R*z:+p}oHy
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publicObject load(finalClass entity, ~Is-^k)y
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finalSerializable id){ -
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return getHibernateTemplate().load Y<9Lqc.i
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(entity, id); tCirdwmg
} DF~{i{
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publicObject get(finalClass entity, `KzNBH,W
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finalSerializable id){ N.qS;%*o{e
return getHibernateTemplate().get y/yg-\/XF
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(entity, id); ICB'?yZ,
} qW'5Zk
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publicList findAll(finalClass entity){ WbDD9ZS
return getHibernateTemplate().find("from EJZb3
L$<(HQQJ8
" + entity.getName()); Fg-4u&Ik
} a]8}zSUK
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publicList findByNamedQuery(finalString T^n0 =|
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namedQuery){ $Y31YA
return getHibernateTemplate u!K5jqP
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().findByNamedQuery(namedQuery); >)`V$x
} vqnFyd
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publicList findByNamedQuery(finalString query, @$%[D`Wa<
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finalObject parameter){ i>n)T
return getHibernateTemplate n8vteGQ
p:q?8+W-r
().findByNamedQuery(query, parameter); 3tIno!|
} b~<Tgo_/jf
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publicList findByNamedQuery(finalString query, 2v9T&xo=
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finalObject[] parameters){ Af{K#R8!
return getHibernateTemplate !$|h[ct
o
9] 2
().findByNamedQuery(query, parameters); &[iunJv:eq
} 8ECBi(
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publicList find(finalString query){ v05B7^1@_
return getHibernateTemplate().find 5/"&C-t
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(query); 0-a[[hL?
} 3a\.s9A"
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publicList find(finalString query, finalObject h`:f
3 h~U)mg
parameter){ 4c/.#?
return getHibernateTemplate().find (S4[,Sx6E
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(query, parameter); `L1lGlt
} o?\v
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public PaginationSupport findPageByCriteria FeAMt
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(final DetachedCriteria detachedCriteria){ $2+(|VG4F
return findPageByCriteria skRI\
#:6gFfk0<
(detachedCriteria, PaginationSupport.PAGESIZE, 0); Kx@;LRY#
} 1l*O;J9By
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public PaginationSupport findPageByCriteria cKbsf^R[e
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(final DetachedCriteria detachedCriteria, finalint
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startIndex){ / %:%la%
return findPageByCriteria 5EqC.g.
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(detachedCriteria, PaginationSupport.PAGESIZE, ~\~K,v
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startIndex); V)g{ Ew]:
} 9?~K"+-SI
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public PaginationSupport findPageByCriteria ?}g#Mc
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(final DetachedCriteria detachedCriteria, finalint ~GZpAPg*
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pageSize, ELWm>'Q#9
finalint startIndex){ t9yjfyk9W
return(PaginationSupport) iAAlld1
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getHibernateTemplate().execute(new HibernateCallback(){ '5BM*4,:O
publicObject doInHibernate Oe^oigcM
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(Session session)throws HibernateException { -6./bB g
Criteria criteria = CF?TW
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detachedCriteria.getExecutableCriteria(session); -WX{y Ci
int totalCount = ?6[X=GeUs
c3NUJ~>=y
((Integer) criteria.setProjection(Projections.rowCount p0S;$dH\D
C@8WY
()).uniqueResult()).intValue(); qIIl,!&}A
criteria.setProjection NtnKS@Ht
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(null); oA1d8*i^E
List items = N=X(G(
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criteria.setFirstResult(startIndex).setMaxResults W7ffdODb
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(pageSize).list(); ;0!rq^JG
PaginationSupport ps = zu8l2(N
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new PaginationSupport(items, totalCount, pageSize, Ao/KB_4f*Q
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startIndex); 9WH
return ps; [8J/#!B
} )K+Tvx3(m
}, true); !ufSO9eDx"
} |GQFNrNx
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public List findAllByCriteria(final AX= 4{b'
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DetachedCriteria detachedCriteria){ a#qC.,$A
return(List) getHibernateTemplate edW:(19}
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().execute(new HibernateCallback(){ <RMrp@[
publicObject doInHibernate [sT}hYh+
ETA 1\
(Session session)throws HibernateException { ?H.7
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Criteria criteria = HAi'0%"
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detachedCriteria.getExecutableCriteria(session); l$s8O0-'T
return criteria.list(); F/qx2E$*wo
} z'FJx2
}, true); Apfs&{Uy
} Qs^RhF\d
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public int getCountByCriteria(final wv eej@zs
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DetachedCriteria detachedCriteria){ GGY WvGE+
Integer count = (Integer) *A,h^
nd 5w|83
getHibernateTemplate().execute(new HibernateCallback(){ !AGjiP$
publicObject doInHibernate 50S >`qi2x
{U,q!<@mq
(Session session)throws HibernateException { 5l&9BS&
Criteria criteria = %Z"I=;=nxI
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detachedCriteria.getExecutableCriteria(session); y_=},a
return u\JYxNj1
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criteria.setProjection(Projections.rowCount qrj:H4#VB
Ak\w)!?s
()).uniqueResult(); fs=W(~"
} :]viLw\&g
}, true); {'QA0K
return count.intValue(); _qPd)V6yb
} ^j1WF[GiSO
} lR9~LNK?
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用户在web层构造查询条件detachedCriteria,和可选的 K`25G_Y3@
X R =^zp?
startIndex,调用业务bean的相应findByCriteria方法,返回一个 yE \dv)(<
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PaginationSupport的实例ps。 lAM"l)Ij
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ps.getItems()得到已分页好的结果集 wd/"! A4(
ps.getIndexes()得到分页索引的数组 5 GP,J,J
ps.getTotalCount()得到总结果数 h zh%ML3L
ps.getStartIndex()当前分页索引 %:P&!F\?
ps.getNextIndex()下一页索引 d4h,
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ps.getPreviousIndex()上一页索引 t&r-;sH^[
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Vko1{$}t
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 !]W}I
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一下代码重构了。 %Q}T9%Mtj
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我把原本我的做法也提供出来供大家讨论吧: -qPYm?$
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首先,为了实现分页查询,我封装了一个Page类: s5s'$|h"
java代码: jH1!'1s|
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/*Created on 2005-4-14*/ o771q}?&`
package org.flyware.util.page; Uv(THxVh
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/** 2xchjU-
* @author Joa %D(%
lh2
* LV:`siK
*/ +=5Dt7/|
publicclass Page { QT5,_+ho
K#B)@W?9
/** imply if the page has previous page */ M-Az2x;6
privateboolean hasPrePage; <fJ*{$[p
$_6DvJ0
/** imply if the page has next page */ =)B@ `"
privateboolean hasNextPage; 3MR4yw5v
LM*#DLadk
/** the number of every page */ _VeZlk7k
privateint everyPage; Kw%n;GFl'
8TK&i,
/** the total page number */ u |hT1l
privateint totalPage; ^_5Nh^
.,C8ASfh
/** the number of current page */ }}";)}C`
privateint currentPage; PKT/U^2X]
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/** the begin index of the records by the current $)5F3a|
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query */ 7>g^OE f
privateint beginIndex; PD$gW`V
s
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/** The default constructor */ (f^K\7HM
public Page(){ n$* 'J9W~
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} tFvc~zz9
Zhl}X!:c?\
/** construct the page by everyPage \\F@_nB,b
* @param everyPage a'LM6A8~x
* */ L6^Qn%:OTd
public Page(int everyPage){ edt(Zzk@3-
this.everyPage = everyPage; [dje!5Dc(
} A6APU><dm^
tN'-4<+
/** The whole constructor */ p/|":(U
public Page(boolean hasPrePage, boolean hasNextPage, Z|YiYQl[)
A9_)}
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int everyPage, int totalPage, ;:JTb2xbb
int currentPage, int beginIndex){ v2>.+Eh#
this.hasPrePage = hasPrePage; pPUv8, %
this.hasNextPage = hasNextPage; HWFI6N
this.everyPage = everyPage; w6k\po=
this.totalPage = totalPage; {iGk~qN
this.currentPage = currentPage; niZ/yW{w
this.beginIndex = beginIndex; IK%fX/tDyc
} f^8,Z+n
p}qNw`
/** C.r9)#G
* @return |2 2~.9S
* Returns the beginIndex. -kp!.c
*/ >&0)d7Nu8m
publicint getBeginIndex(){ RO-ABFEi(
return beginIndex; ;?/v}$Pa
} Ou~|Q&f'
qB`zyd8yu
/** #`tn:cP
* @param beginIndex 6Q&R,"!$p
* The beginIndex to set. U*G9 fpVy
*/ [vuqH:Ln
publicvoid setBeginIndex(int beginIndex){ K)|#FRPM u
this.beginIndex = beginIndex; 6{rH|Z
} fqaysy
5>J{JW|
/** A^PCI*SN[
* @return CD\k.
* Returns the currentPage. ]XX8l:+
*/ BJgg-z{Y
publicint getCurrentPage(){ YYrXLt:
return currentPage; ;dt&*]wA
} _y Q*
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/** XG
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* @param currentPage nwlo,[
* The currentPage to set. Y[=Gv6Fr
*/ Jsi [,|G
publicvoid setCurrentPage(int currentPage){ Gld|w=qr
this.currentPage = currentPage; 6Sh0%Fs
}
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/** r>N5^
* @return #4. S2m4
* Returns the everyPage. $O*rxQ}
*/ 2| u 'J
publicint getEveryPage(){ 9/OB!<*V|
return everyPage; krkRP%jy
} c?i=6CdD'
KsM2?aqwf_
/** i7:R4G(/#
* @param everyPage i]{M G'tg
* The everyPage to set. 41y}n{4n8
*/ .aWEXJ
publicvoid setEveryPage(int everyPage){ :]%z8,6k
this.everyPage = everyPage; ,bRvj8"M
} jq{rNxdGx
,^MA,"8
/** gd>Op
* @return |r"1
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* Returns the hasNextPage. Sr)rKc
*/ q^],K'
publicboolean getHasNextPage(){ Zfyr&]"
return hasNextPage; {s} @$rW
} wy5vn?T@
t.m65
/** OHeVm-VC
* @param hasNextPage * iW>i^
* The hasNextPage to set. zR2'xE*
*/ cDMA#gp
publicvoid setHasNextPage(boolean hasNextPage){ 3R%'<MV|
this.hasNextPage = hasNextPage; (,eH*/~/
} mjbr}9
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/** g+gHIb7{
* @return (q+U5Ls6
* Returns the hasPrePage. 0eY$K7
U
*/ "=I
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publicboolean getHasPrePage(){ lJ!+n<K+
return hasPrePage; {uEu
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} J2_D P
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/** ye1kI~LO(
* @param hasPrePage L 0kK' n?
* The hasPrePage to set. !n4p*<Y6
*/ kQXtO)
publicvoid setHasPrePage(boolean hasPrePage){ gio'_X
this.hasPrePage = hasPrePage; 3IHya=qN
} Wd'wL"6De
o
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/** w~>V2u_-
* @return Returns the totalPage. }0c
* Ex35
*/ Wbc*x
publicint getTotalPage(){ xe[Cuy$P
return totalPage; *Got
} e$|g
)
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/** %7q,[g8
* @param totalPage AZ cWf8
* The totalPage to set. T'2(sHk
*/ 3X,9K23T
publicvoid setTotalPage(int totalPage){ H)1< ;{:
this.totalPage = totalPage; xfw)0S
} S2/c2
|S#)[83*3
} 4`uI)N(}*
| Euf:yWY
M
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 rgheq<B:
weC$\st:D
个PageUtil,负责对Page对象进行构造: SLRQ3<0W_
java代码: (u@p[ncN}
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/*Created on 2005-4-14*/ `V[{(&?,n
package org.flyware.util.page; +~Ri CZt
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import org.apache.commons.logging.Log; a2fV0d6*l
import org.apache.commons.logging.LogFactory; *,!6#Z7
$d.UF!s
/** 1{R1:`
* @author Joa 'Uqz ,
* R+IT)2
*/ :.Vn
publicclass PageUtil { XEMi~L+
lil1$K: i
privatestaticfinal Log logger = LogFactory.getLog bY7d
D]resk
(PageUtil.class); 5=/H2T!F
i[A$K~f
/** ,o\vumx
* Use the origin page to create a new page !u@e^J{Ao
* @param page fLl~a[(5
* @param totalRecords ai[st+1
* @return WP7*Q:5
*/ };!S2+
publicstatic Page createPage(Page page, int GMRw+z4
`yJpDGh
totalRecords){ !]7r>NS>
return createPage(page.getEveryPage(), '"Q;54S**
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page.getCurrentPage(), totalRecords); hkeOe
} d(zBd=;
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/** 37Vs9w
* the basic page utils not including exception %g}ri8
PvX>+y5
handler
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* @param everyPage P#bZtWx'<N
* @param currentPage !\.x7N<)0
* @param totalRecords *j RNpB{)z
* @return page 7*]O]6rP
*/ ?n9gqwO
publicstatic Page createPage(int everyPage, int _n(O?M&x
'ek7e.x|V
currentPage, int totalRecords){ EQXvEJ^
everyPage = getEveryPage(everyPage); l[mXbQd
currentPage = getCurrentPage(currentPage); V~`
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int beginIndex = getBeginIndex(everyPage, XfmPq'#Z
57^X@ra$
currentPage); RSXYz8{
int totalPage = getTotalPage(everyPage, yZ=wT,Y
|13UJ
vR
totalRecords); @#$5_uU8\(
boolean hasNextPage = hasNextPage(currentPage, _oxhS!.*
6hQ?MYX
totalPage); ]Ec\!,54u
boolean hasPrePage = hasPrePage(currentPage); wB}s>o\
k2o98bK&;
returnnew Page(hasPrePage, hasNextPage, Q.Tn"rE|
everyPage, totalPage, 8R}CvzI
currentPage, NL%5'8F>,
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beginIndex); {b~l[
} l -us j%\
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X
privatestaticint getEveryPage(int everyPage){ <5
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return everyPage == 0 ? 10 : everyPage; #-kG\}
} >AI65g
;HRIB)wF
privatestaticint getCurrentPage(int currentPage){ `8xt!8Z$
return currentPage == 0 ? 1 : currentPage; S*<+vIo
} 7<['4*u
).e_iE[&
privatestaticint getBeginIndex(int everyPage, int \?A 7{IY
!=M[u+-
currentPage){ :4|ubu
return(currentPage - 1) * everyPage; +c!v%uX
} Ub!MyXd{q
$lmGMljF
privatestaticint getTotalPage(int everyPage, int Hy~kHBIL
(<!Yw|~
totalRecords){ jC7`_;>=
int totalPage = 0; YNV4w{>FD
qV2aa9p+
if(totalRecords % everyPage == 0) #]pFE.o
totalPage = totalRecords / everyPage; T7_i:HU%
else eSNi6RvE
totalPage = totalRecords / everyPage + 1 ; '=}F}[d"kk
J P'|v"
return totalPage; &y"e|aE
} !2>MaV1,
Kk|uN#m
privatestaticboolean hasPrePage(int currentPage){ /ghXI"ChI
return currentPage == 1 ? false : true; Lq.aM.&;#
} ibo{!>m
FYh+G-Y#
privatestaticboolean hasNextPage(int currentPage, ^\:"o
udYk
6
int totalPage){ +Zgh[a
return currentPage == totalPage || totalPage == 9M{z@H/
nw|ls2
0 ? false : true; X;/~d>@
} 60?/Z2w5
2;N)>[3*J
v;4l*)$)
} #wn`choT'
Ao>] ~r0
GqB]^snh
V4kt&61
AdV&w: ^yf
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。 H<bYm]a%
jt9fcw
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 @X\-c2=
Bbk=0+ ^8I
做法如下: a(-
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1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 2)oT\m
Kppi
N+ ||
的信息,和一个结果集List: %!Z9: +;B
java代码: {x$WBy9
<2Q+? L{
1#BMc%
/*Created on 2005-6-13*/ %DH2]B? 0
package com.adt.bo; e%_2n=p~)%
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import java.util.List; @T>\pP]o
>S\D+1PV
import org.flyware.util.page.Page;
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/** aYc*v5QN3
* @author Joa ft$@':F
*/ 'a8{YT4
publicclass Result { Fo
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X.^S@3[
private Page page; i> }P V
i}d^a28
private List content; $2lrP]`>j.
<7-Qn(m,
/** zF'LbQz0[
* The default constructor Lh eOGM
*/ DL$O274uZ
public Result(){ XNODDH
super(); `<}Q4p
} dV_ClH &)
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/** /{h@A~<96
* The constructor using fields /1A3
Sw
* NrQGoAOw
* @param page -2Bkun4Pt
* @param content #6w\r&R6
*/ %NH#8#';2
public Result(Page page, List content){ /Z':wu\
this.page = page; 3QNu7oo
this.content = content; |"t)#BUtL
} 1>5l(zK!9
hsYS<]
/** U tb"6_
* @return Returns the content. L;jzDng<
*/ :x85:pa
publicList getContent(){ ,mkXUW
return content; |%p;4b
} l;+nL[%`
M1UabqQ
/** b8Bf,&:ys
* @return Returns the page. B4fMD]
*/ (6b*JQ^^
public Page getPage(){ )w3?o#@
return page; *2nQZ^c.
} 8OV;&Z,x
[w>T.b
/** H]i.\2z
* @param content c*fMWtPp
* The content to set. G3[X.%g`
*/ 'MF|(`
public void setContent(List content){ G3Z>,"w;=
this.content = content; {0~ Sj%Ze
} suo;+T=`I
hrT!S
/** |r|<cc#
* @param page i-kj6N5
* The page to set. o p{DPUO0
*/ H@-txO1`::
publicvoid setPage(Page page){ */8b)I}yY
this.page = page; ->H4!FS
} yaDK_fk
} ,}8|[)"
M{!Y
7IEG%FY
T
Nj p?/r
!Eqp,"ts7
2. 编写业务逻辑接口,并实现它(UserManager, utH/E7^8
M&93TQU-
UserManagerImpl)
4y:pj7h
java代码: G@.TE7a2Z
!@.9>"FU
Z30r|Ufh
/*Created on 2005-7-15*/ T(@J]Y-
package com.adt.service; vJ&g3ky
_"4u?C#
import net.sf.hibernate.HibernateException; [5"F=tT7WP
sYMgi D
import org.flyware.util.page.Page; jPDk~|
L\GjG&Y5
import com.adt.bo.Result; mi`jY0e2
YA?46[:
/** $;k2b4u
* @author Joa 2#y-3y<G
*/ Qp?+G~*
publicinterface UserManager { [B2g{8{!
CO<P$al
public Result listUser(Page page)throws MS>QU@z7c
n7>L&?N#y#
HibernateException; U8||)+
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} $\9M6k'
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$'I-z.G V
Dr_ (u<[
zJMm=Mw^
java代码: Yg~$1b@
A.8[FkiNmD
NUQ?QQ
/*Created on 2005-7-15*/ uOv0ut\\G
package com.adt.service.impl; $~h\`vF&
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0wV3Qv
import java.util.List; gfPR3%EXs
'xG:v)(
import net.sf.hibernate.HibernateException; CAJ]@P#Xj+
Y3n6y+Uzk
import org.flyware.util.page.Page; Y}n$s/O:u8
import org.flyware.util.page.PageUtil; DwNEqHi
S.! n35
import com.adt.bo.Result; W }"n*
import com.adt.dao.UserDAO; (+iOy/5#u
import com.adt.exception.ObjectNotFoundException; dEvjB"x
import com.adt.service.UserManager; p7Xe[94d^
>[qoNy;
/** qhQeQ
* @author Joa Zr#\>h 'c
*/ S=^kR [O"
publicclass UserManagerImpl implements UserManager { ?c6`p3p3L
\F'tl{'\@
private UserDAO userDAO; #GVf+8"
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/** 0!5w0^1
* @param userDAO The userDAO to set. Vx#n0z
*/ UVUoXv)N
publicvoid setUserDAO(UserDAO userDAO){ ,ozgnhZY
this.userDAO = userDAO; jqJ't)N
} #Aver]eK
4\pUA4
/* (non-Javadoc) Tw]].|^f-
* @see com.adt.service.UserManager#listUser B]lM69Hz
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(org.flyware.util.page.Page) AEw~LF2w
*/ B*AF8wX|
public Result listUser(Page page)throws >S[NI<=8S
h3YWqSj
HibernateException, ObjectNotFoundException { SKdh!*G
int totalRecords = userDAO.getUserCount(); c*N>7IF,
if(totalRecords == 0) XPfheV G
throw new ObjectNotFoundException ')82a49eA
_q1b3)`D
("userNotExist"); lmbC2\GT
page = PageUtil.createPage(page, totalRecords); T[\?fSP
List users = userDAO.getUserByPage(page); a
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returnnew Result(page, users); wticA#mb
} >&?k^nI}J
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} ^)%TQ.
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3qVDHDQ?ZV
rsPo~nA
}M|,Z'@*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 .?NraydwV
D6NgdE7b
询,接下来编写UserDAO的代码: F&6Xo]?
3. UserDAO 和 UserDAOImpl: bL9XQ:$C
java代码: 4RDdfY\%u
U:+wt}-T"
Y$K[@_dv=
/*Created on 2005-7-15*/ SLi?E
package com.adt.dao; .DN)ck:e;
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import java.util.List; 5m\T~[`%
+m]Kj3-z@
import org.flyware.util.page.Page; gu|cQ2xV
Qs
#7<NQ
import net.sf.hibernate.HibernateException; wxW\L!@
NA-)7i*>J
/** {[Z}<#n)
* @author Joa I?~iEO\nh
*/ /xh/M@G3
publicinterface UserDAO extends BaseDAO { 1
[D,Mu%E
1@6FV x
publicList getUserByName(String name)throws 6U?z
grbUR)f<?-
HibernateException; ?_BK(kL_
yRtxh_wr9
publicint getUserCount()throws HibernateException;
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cwC-)#R']
publicList getUserByPage(Page page)throws WcZck{ehd
o >?#$~XNv
HibernateException; k=``Avp?
01&J7A2
} )2dTgvy
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;'7gg]
? 1
~C`I;
` Clh;
java代码: 5fuB((fd(
|x$2-RUP
Qk#`e
/*Created on 2005-7-15*/ ]zUvs6ksLG
package com.adt.dao.impl; TBr@F|RXiO
d"~-D;
import java.util.List; {~a+dEz
4O1[D?)`x
import org.flyware.util.page.Page; qpZR-O
DD^iEhG
import net.sf.hibernate.HibernateException; /j(3 ~%]o4
import net.sf.hibernate.Query; k*"FMJG_
O$,bNu/g
import com.adt.dao.UserDAO; rJws#^]
z]33_[G1U
/** 1_V',0|`>
* @author Joa :I/i"g7<
*/ U%T{~f
public class UserDAOImpl extends BaseDAOHibernateImpl bS"zp6Di
r?:xD(}Q
implements UserDAO { PZE{-TM?W
ZT1IN6;8W
/* (non-Javadoc) ,I^:xw_
* @see com.adt.dao.UserDAO#getUserByName #a|.cm>6
'~;vp
(java.lang.String) S :%SarhBD
*/ *fg|HH+i
publicList getUserByName(String name)throws BELxaV,
SM1[)jZ-
HibernateException {
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String querySentence = "FROM user in class _+NM<o#A
HHXm
4}!;<
com.adt.po.User WHERE user.name=:name"; MQ7Hn;`B
Query query = getSession().createQuery OK \F
l?J|Ip2W
(querySentence); WIkr0k
query.setParameter("name", name); D
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return query.list(); ZGZ+BOFL
} #!RO,{FT
N}5'Hk4+
/* (non-Javadoc) VyWPg7}e
* @see com.adt.dao.UserDAO#getUserCount() dSq3V#Q
*/ .Mz'h9@
publicint getUserCount()throws HibernateException { X|wg7>kh*`
int count = 0; JVawWw0q
String querySentence = "SELECT count(*) FROM :0'2m@x~
)"4v0dv
user in class com.adt.po.User"; *p=a-s5-
Query query = getSession().createQuery 2Pz)vnV"
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(querySentence); N "Mw1R4
count = ((Integer)query.iterate().next T]0H&Oov
lk`,s
()).intValue(); ),;O3:n
return count; c
D0-g=&
} ;[R#:Rk
[Z$E^QAP
/* (non-Javadoc) \\{+t<?J
* @see com.adt.dao.UserDAO#getUserByPage RZrQ^tI3"
Y24H`
s1u/
(org.flyware.util.page.Page) OS7^S1r-
*/ Z@d(0 z
publicList getUserByPage(Page page)throws V9cKl[
RhQ[hI
HibernateException { 3X#)PX9b){
String querySentence = "FROM user in class 3wf&,4`EX
y L|'K}
com.adt.po.User"; 9fQFsI
Query query = getSession().createQuery 3sF^6<E
hCFgZiH2
(querySentence); [8$K i$;
query.setFirstResult(page.getBeginIndex()) 0kOl,%Ey
.setMaxResults(page.getEveryPage()); =>en<#[\:
return query.list(); Yp(F}<f?
} &/-^D/ot
9#iv|X
} ^oYudb^%
unZYFA}(
A1uo@W
`Eq~W@';Q0
MeMSF8zSQ
至此,一个完整的分页程序完成。前台的只需要调用 NPY\ >pf
f&ri=VJY\T
userManager.listUser(page)即可得到一个Page对象和结果集对象 ;eQOBGX9
VsR8|Hn$
的综合体,而传入的参数page对象则可以由前台传入,如果用 L^><APlX
DJ.n8hne
webwork,甚至可以直接在配置文件中指定。 M>LgEc-v67
Vq>$ZlvS
下面给出一个webwork调用示例: 4k4 d%
java代码: G ,fh/E+
' En|-M5
"s3eO
/*Created on 2005-6-17*/ *uG!U%jY)
package com.adt.action.user; eemw
I
D_2~
6
import java.util.List; 9Impp5`/B
uW4wTAk;qh
import org.apache.commons.logging.Log; A$Tp0v`t
import org.apache.commons.logging.LogFactory; H68~5lJY^]
import org.flyware.util.page.Page; 7 S6@[-E
&upM,Jsr*
import com.adt.bo.Result; CYFi_6MFl
import com.adt.service.UserService; s.qo/o\b
import com.opensymphony.xwork.Action; W _JGJV.^f
_ 0g\g~[
/** q47:kB{d
* @author Joa .XTR
HL*:
*/ ]~!?(d!J/
publicclass ListUser implementsAction{ Al-;-t#Dc
PT/TQW
privatestaticfinal Log logger = LogFactory.getLog '2X6>6`w
:Y)jf
(ListUser.class); %3;vDB*L$
O}w"@gO@.
private UserService userService;
BWG*UjP
M
"J(0J
private Page page; ,C97|6rC
NcMohpkq
privateList users; AAW])c`.
/|MHZ$Y9w?
/* LfsqtQ=J`
* (non-Javadoc) mtd ,m
* pEp`Z,p
* @see com.opensymphony.xwork.Action#execute() 2*)2c[/0F
*/ K~6,xZlDWM
publicString execute()throwsException{ rU!QXg]uD
Result result = userService.listUser(page); 4#"_E:;PQ
page = result.getPage(); HY!R |
users = result.getContent(); ky#5G-X
return SUCCESS; K*id
1YY
} c+A$ [
4-vo R5Fd
/** }"x#uG
* @return Returns the page. ]:_s7v
*/ 8Z[YcLy"({
public Page getPage(){ `WRM7
return page; $s.:H4:I
} j0`)m R}
K6d2}!5
/** {a9(
Qi
* @return Returns the users. <reALC
*/ 0Fc^c[
publicList getUsers(){ 0ub0[A
return users; >K;DBy*
} =IH~:D\&
o|G[/o2
/** XDQ5qfE|
* @param page c$P68$FB
* The page to set. Cno+rmsfT
*/ 1Wr,E#+C
publicvoid setPage(Page page){ Nbvs_>N
this.page = page; |w].*c}Z
} #T3dfVWv
cKEDRX3
/** h"3Mj*s
* @param users ;1AXu/
* The users to set. m-u0U
*/ H5!e/4iz
publicvoid setUsers(List users){ 1tIJ'#6
this.users = users; 4^(aG7
}
YG_|L[/#
PK).)5sW
/** d+o.J",E
* @param userService C2} f'
* The userService to set. 4H4ui&|7u6
*/ 7z;X@+O}s
publicvoid setUserService(UserService userService){ 3ZUME\U
this.userService = userService; q,m+W='
} lx\9 Y 8
} q5xF~SQGw2
Us2IeR
>r\q6f#J4
`F`{s`E)
L6x;<gj
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, )lZoXt_3
Rn$[P.||
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 {&ykpu090
\@B'f
么只需要: G_]zymXQ
java代码: o]M1$)>b+
lc[)O3,,B
(L<qJd1Q
<?xml version="1.0"?> G
_-JR
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork hN^,'O
.]w=+~h
1.0//EN" "http://www.opensymphony.com/xwork/xwork- K1$
F}~qTF;H
1.0.dtd"> vzFo"
0,whTnH|
<xwork> dym K @
}0V aZ<j
<package name="user" extends="webwork- 4w5);x.
#w@V!o
interceptors"> Qo~|[]GE
J'C9}7G
<!-- The default interceptor stack name ;-AC}jG
XR_Gsb%l
--> E?-
~*T
<default-interceptor-ref HA74s':FN
0[]) wl
name="myDefaultWebStack"/> V+5av Z}
v`@M IOv
<action name="listUser" i__f%j`!W
bae;2| w
class="com.adt.action.user.ListUser"> R-YNg
<param A <_{7F9
ON9L+"vqv0
name="page.everyPage">10</param> !oa/\p
<result Rt>mAU$}
goe%'k,
name="success">/user/user_list.jsp</result> .*edaDi
</action> +ib&6IU
(q@%eor&}
</package> hg2Ywzfm-
[}HS[($
</xwork> ik#ti=.
H'+3<t>
!dq$qUl/
*ze,X~8-
V|G*9^Y
3rBID
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 WjguM
: T{VCw:*
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 gBr/Y}I
1~Z
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 K@%gvLa\
1-$+@Xl
2wu\.{6Zp
dVg'v7G&V(
Ma4eu8
我写的一个用于分页的类,用了泛型了,hoho vi.INe
R^B8** N
java代码: NxSSRv^rx
*zQhTYY
h=Q2
?O8
package com.intokr.util; VTU(C&"S
eA*We
import java.util.List; fA"c9(>m%]
Q zg?#|
/** Hy5 6@jW+E
* 用于分页的类<br> 6L rI,d
* 可以用于传递查询的结果也可以用于传送查询的参数<br> *R}p9;dpO
* ]ddH>y&o
* @version 0.01 V-3;7
* @author cheng Cp+tcrd_s
*/ Fi/`3A@68
public class Paginator<E> { :}2T of2
privateint count = 0; // 总记录数 hBaF^AWW
privateint p = 1; // 页编号 j\"d/{7Q
privateint num = 20; // 每页的记录数 Lr9E02
privateList<E> results = null; // 结果 k<