Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 <
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 lE(HFal0-(
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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 .:%0E`E
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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 1FL~ndJs
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。 Q1I6$8:7
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分页支持类: \aUC(K~o\;
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java代码: &>W$6>@
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package com.javaeye.common.util; `w7v*h|P
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import java.util.List; S3*`jF>q
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publicclass PaginationSupport { =M[bnq*\
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publicfinalstaticint PAGESIZE = 30; qUW!
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privateint pageSize = PAGESIZE; G3vxjD<DMW
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privateList items; UapC"XYJ
aU "8{
privateint totalCount; li'YDtMKCY
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privateint[] indexes = newint[0]; '/n1IM$7
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privateint startIndex = 0; *-=(Q`3
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public PaginationSupport(List items, int D4lG[qb
}mYx_=+VX
totalCount){ F Q7T'G![
setPageSize(PAGESIZE); )@l%
setTotalCount(totalCount); 8f)?{AX0
setItems(items); Fg5kX
setStartIndex(0); kYqU9cB~
} 6azGhxh
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public PaginationSupport(List items, int $=8
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j@U]'5EVB
totalCount, int startIndex){ nn:.nU|I
setPageSize(PAGESIZE); Vvn2 Ep
setTotalCount(totalCount); ~hnQUS`A
setItems(items); ll<Xz((o
setStartIndex(startIndex); oim9<_
} iohop(LZ
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public PaginationSupport(List items, int ~ Ei $nV
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totalCount, int pageSize, int startIndex){ 5T_n %vz
setPageSize(pageSize); a LroD$#
setTotalCount(totalCount); EyD=q! ZVZ
setItems(items); /ivJsPH
setStartIndex(startIndex); B:;pvW]
} |mdVdD~go
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publicList getItems(){ j^j1
return items; 3nIU1e
} ]Yn D
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publicvoid setItems(List items){ yYIf5S`V]
this.items = items; dUeN*Nq&(,
} KQaxvU)L
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publicint getPageSize(){ t9k zw*U9
return pageSize; 7u -p%eq2
} (Y.k8";)`
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publicvoid setPageSize(int pageSize){ n71r_S*
this.pageSize = pageSize; Gv!2f
} EnKR%Ctw
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publicint getTotalCount(){ &=@IzmA
return totalCount; $B2J
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} ="1Ind@w!
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publicvoid setTotalCount(int totalCount){ :KSV4>X[%a
if(totalCount > 0){ rKe2/4>0X
this.totalCount = totalCount; fy>{QC\
int count = totalCount / aD<A.Lhy
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pageSize; )al]*[lY
if(totalCount % pageSize > 0) -]N
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count++; 9tU]`f
indexes = newint[count]; ''A_[J `>
for(int i = 0; i < count; i++){ [N-Di"
indexes = pageSize * e&|'I"
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i; SB;&GHq"n
} G, }Yl
}else{ }/0X'o
this.totalCount = 0; \#2Z)Kz
} j"t(0m
} WrnrFz
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publicint[] getIndexes(){ du
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return indexes; "(3[+W{|
} SXSgld2uS
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publicvoid setIndexes(int[] indexes){ bQzZy5,
this.indexes = indexes; xeg/A}yE
} )nC]5MXU
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publicint getStartIndex(){ 7cuE7"
return startIndex; WA<v9#m
} \#8D>i?m
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publicvoid setStartIndex(int startIndex){ euK5pA>L
if(totalCount <= 0) mxvp3t \
this.startIndex = 0; b<tNk]7
elseif(startIndex >= totalCount) >2Y=*K,:
this.startIndex = indexes ]{;gw<T
$g^@AdE%
[indexes.length - 1]; ]}>2D,;
elseif(startIndex < 0) 6B8VfQ9[
this.startIndex = 0; z 4e7PW|
else{ =Pyj%4Rs
this.startIndex = indexes prUN)r@U
P7[h-3+^
[startIndex / pageSize]; frm>4)9+
} lne|5{h
} BwN0!lsF3
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publicint getNextIndex(){ juP7P[d$qW
int nextIndex = getStartIndex() + =eq[:K<6
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pageSize; 7zl5yKN
if(nextIndex >= totalCount) PF0_8,@U
return getStartIndex(); ^Y?k0z
else #z'
return nextIndex; M:=J^0
} :;v~%e{k
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publicint getPreviousIndex(){ cRC6 s8
int previousIndex = getStartIndex() - +X\FBvP&
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pageSize; vJLK,[
if(previousIndex < 0) s2a{>II6
return0; {Ea
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else xf'V{9*
return previousIndex; "-E\[@/
} "6("9"
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} nd`1m[7MNu
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Q*GN`07@?d
抽象业务类 `](e:be}
java代码: qfX6TV5J}!
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/** E[OJ+ ;c
* Created on 2005-7-12 !OZy7
*/ s$IDLs,WM
package com.javaeye.common.business; [=C6U_vU
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import java.io.Serializable; j<u pRS,$
import java.util.List; PhLn8jNti
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import org.hibernate.Criteria; ^"E^zHM(
import org.hibernate.HibernateException; 9p85Pv [M=
import org.hibernate.Session; [\]50=&
import org.hibernate.criterion.DetachedCriteria; :S]%6gb8G
import org.hibernate.criterion.Projections; 1> ?M>vK
import IZf{nQ[0
bt SRtf
org.springframework.orm.hibernate3.HibernateCallback; Fk7?xc
import qyb?49I
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org.springframework.orm.hibernate3.support.HibernateDaoS UhF-K#Z9
;T\%|O=Ke
upport; SZ7:u895E
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import com.javaeye.common.util.PaginationSupport; l03B=$
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public abstract class AbstractManager extends 2F;y;l%
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HibernateDaoSupport { Xxj-
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privateboolean cacheQueries = false; Mc
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privateString queryCacheRegion; R>|{N9
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publicvoid setCacheQueries(boolean -
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cacheQueries){ +bxYGD
this.cacheQueries = cacheQueries; KRbvj
} c2SO3g\"i
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publicvoid setQueryCacheRegion(String e)IzQ7Zex
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queryCacheRegion){ te`$%NRl
this.queryCacheRegion = |T /ZL!
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queryCacheRegion; AOZP*\k
} Y;eZ9|Ht9
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publicvoid save(finalObject entity){ Z{.8^u1I
getHibernateTemplate().save(entity); NSMyliM1Y
} BU)U/A8iS
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publicvoid persist(finalObject entity){ &<g|gsG`
getHibernateTemplate().save(entity); f^ZRT@`O
} Rr$-tYy6
Oxnp0 s
publicvoid update(finalObject entity){ FgnTGY}
getHibernateTemplate().update(entity); t^-d/yKt0w
} R+:yVi[F]U
_%Bi: HG0
publicvoid delete(finalObject entity){ =[ 46`-_
getHibernateTemplate().delete(entity); z|uDy2
} .#!lP/.eQP
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publicObject load(finalClass entity, jwe *(k]z
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finalSerializable id){ 3yme1Mb
return getHibernateTemplate().load Mexk~zA^
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(entity, id); Rh2+=N<X
} OKZV{Gja
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publicObject get(finalClass entity, A|[?#S((]
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finalSerializable id){ `RT>}_j
return getHibernateTemplate().get iXkF1r]i
qbr$>xH
(entity, id); ^6x%*/l|
} Hvauyx5T
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publicList findAll(finalClass entity){ G't$Qx,IC
return getHibernateTemplate().find("from f)rq%N &
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" + entity.getName()); S7 2+d%$
} YaqR[F
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publicList findByNamedQuery(finalString @IKYh{j4
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namedQuery){ ;;Y!^^g
return getHibernateTemplate pX<`+t[
v"$L702d$\
().findByNamedQuery(namedQuery); tT8%yG}
} 2|y"!JqE1
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publicList findByNamedQuery(finalString query, SR
hiQ
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finalObject parameter){ GVr1`l
return getHibernateTemplate TqQB@-!
/HEw-M9z
().findByNamedQuery(query, parameter); s[*rzoA
} .sW|Id )
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publicList findByNamedQuery(finalString query, Wb_J(!da
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finalObject[] parameters){ @;4zrzQi7
return getHibernateTemplate G>=*yqo
octL"t8w
().findByNamedQuery(query, parameters); C&f=
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} l30EKoul)
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publicList find(finalString query){ @{e}4s?7od
return getHibernateTemplate().find ]q[D>6_
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(query); ~/U1xk%
} [aLI
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publicList find(finalString query, finalObject B@))8.h]
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parameter){ I{&[[7H
return getHibernateTemplate().find :=V[7n])
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(query, parameter); :4w ?#
} U>SShpmZA
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public PaginationSupport findPageByCriteria Pm?KI<TH~
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(final DetachedCriteria detachedCriteria){ `[yKFa
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return findPageByCriteria #z%fx
kH1~k,|\&K
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 'oVx#w^mf
} ">nxHU
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint H41?/U,{
ty!`T+3
startIndex){ Qel9G($=
return findPageByCriteria hZ,_6mNg
I
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(detachedCriteria, PaginationSupport.PAGESIZE, a-tmq]]E
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startIndex); Rv>-4@fMJ
} #X$\&,Yn"
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}E
public PaginationSupport findPageByCriteria ,qwuLBW
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(final DetachedCriteria detachedCriteria, finalint = svN#q5s
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pageSize, wJqMa9|
finalint startIndex){ o/)h"i0P
return(PaginationSupport) JR|ck=tq
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getHibernateTemplate().execute(new HibernateCallback(){ HJH{nz'Lw
publicObject doInHibernate RB\uK
1+
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(Session session)throws HibernateException { pki%vRY
Criteria criteria = 6@!`]tSCK
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detachedCriteria.getExecutableCriteria(session); 0mVNQxHI
int totalCount = qR{=pR
hfTY.
((Integer) criteria.setProjection(Projections.rowCount ?^{Ah}x
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()).uniqueResult()).intValue(); %1L,Y
criteria.setProjection kD%( _K5
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(null); n@i HFBb
List items = WwFm*4{[o
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criteria.setFirstResult(startIndex).setMaxResults z<;HQX,
Or+U@vAnk
(pageSize).list(); _[3D
PaginationSupport ps = +sA2WK]
|df Pki{
new PaginationSupport(items, totalCount, pageSize, xo&_bMO
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startIndex); b%`1cV
return ps; ;'K5J9k
} J8(lIk:e
}, true); J@'wf8Ub
} ITBE|b
p
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public List findAllByCriteria(final 3$R1ipb
e !Y~Qy
DetachedCriteria detachedCriteria){ !pW0qX\1n
return(List) getHibernateTemplate T^KKy0ZGM
59A}}.@?m
().execute(new HibernateCallback(){ )akoa,#%6c
publicObject doInHibernate LL!Dx%JZ
8<.Oq4ku
(Session session)throws HibernateException { Il'fL'3
Criteria criteria = t*u:hex
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detachedCriteria.getExecutableCriteria(session); <'*LRd$1
return criteria.list(); ]ieeP4*
} ;^*W+,4WB
}, true); *)Zdz9E'1(
} f6Ah6tb
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public int getCountByCriteria(final oc`H}Wvn
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DetachedCriteria detachedCriteria){ 3 0H?KAV
Integer count = (Integer) 0e4{{zQx
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getHibernateTemplate().execute(new HibernateCallback(){ bd-L`={j
publicObject doInHibernate 7NGxa6wi
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(Session session)throws HibernateException { 5;EvNu
Criteria criteria = L4HI0Mx
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detachedCriteria.getExecutableCriteria(session); jLluj
return R/YqyT\SM
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criteria.setProjection(Projections.rowCount %h@EP[\
&8lZNv8;(p
()).uniqueResult(); e"<OELA
} VPo".BvG6
}, true); ,zjv7$L
return count.intValue(); .k !{*
} {wKB;?fUvk
} lf,5w
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用户在web层构造查询条件detachedCriteria,和可选的 g7H(PF?
1qA;/-Zr<o
startIndex,调用业务bean的相应findByCriteria方法,返回一个 {IjR^J=k
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PaginationSupport的实例ps。 "y}5;9#,
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ps.getItems()得到已分页好的结果集 9.#<b|g
ps.getIndexes()得到分页索引的数组 mfr|:i
ps.getTotalCount()得到总结果数 z{QqY.Gu{G
ps.getStartIndex()当前分页索引 W=?<<dVYD
ps.getNextIndex()下一页索引 ?J0y|
ps.getPreviousIndex()上一页索引 Bzf^ivT3L
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 8s@3hXD&
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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 !N^@4*
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一下代码重构了。 gSj,E8-g
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我把原本我的做法也提供出来供大家讨论吧: OyIw>Wfv
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首先,为了实现分页查询,我封装了一个Page类: tH4B:Bgj!
java代码: #'`{Qv0,
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/*Created on 2005-4-14*/ n@3>6_^rwT
package org.flyware.util.page; Q>z8IlJ}
.}+}8[p4l
/** *-X[u:
* @author Joa %BODkc Zh
* UiNP3TJ'L
*/ V;=cwy)I
publicclass Page { {!`6zBsP
#vlgwA
/** imply if the page has previous page */ lOp`m8_=
privateboolean hasPrePage; 8@R|Km5h
Fr-SvsNFB
/** imply if the page has next page */ (8OsGn
privateboolean hasNextPage; 3so%gvY.'
"dlVk~
/** the number of every page */ /-s6<e!
privateint everyPage; |s_GlJV.
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/** the total page number */ #dHa,HUk
privateint totalPage; yhJ@(tu.Gd
:4|4 =mkr
/** the number of current page */ !)$Zp\Sg
privateint currentPage; XWw804ir
{;oPLr+Z
/** the begin index of the records by the current J}t%p(mb
:(%5:1W
query */ lTsjxw
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privateint beginIndex; "@ n%Z
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/** The default constructor */ mE[y SrV
public Page(){ V]^$S"Tv
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} An@t?#4gxi
ssL\g`xe
/** construct the page by everyPage xSu >
* @param everyPage F0#
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* */ *zLMpL_
public Page(int everyPage){ 5r0YA
IJ
this.everyPage = everyPage;
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} 30{ gI0jk
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/** The whole constructor */ $[|mGae
public Page(boolean hasPrePage, boolean hasNextPage, *1"+%Z^
=~gvZV-<
a'T;x`b8U,
int everyPage, int totalPage, dr"1s-D4IQ
int currentPage, int beginIndex){ ~J]qP #C
this.hasPrePage = hasPrePage; rl.}%Ny
this.hasNextPage = hasNextPage; 7 8,n%=nG
this.everyPage = everyPage; X3&
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this.totalPage = totalPage; 1~gCtBRM
this.currentPage = currentPage; PY'2h4IL
this.beginIndex = beginIndex; 2<6UwF
} p7~!z.)o
!x)R=Z/C
/** k7^5Bp8=
* @return ,%y/kS]
* Returns the beginIndex. HZOMlOZ
*/ ?]5qr?W%
publicint getBeginIndex(){ OrW
return beginIndex; u?EN
} F"kAkX>3}
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/** 3g
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* @param beginIndex `0svy}
* The beginIndex to set. /kG_*>.Z
*/ /_.|E]
publicvoid setBeginIndex(int beginIndex){ IGgL7^MF
this.beginIndex = beginIndex; ,: ^u-b|
} ~"bVL[
*^r}"in
/** o;*Q}Gr<M
* @return fV~~J2IK
* Returns the currentPage. _v:SP
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*/ ` %}RNC
publicint getCurrentPage(){ 3U}%2ARo_
return currentPage; ^f@=:eWI
} [><Tm\(:
=|9!vzG4
/** 3$/IC@+
* @param currentPage ';"VDLb3
* The currentPage to set. MOC/KNb
*/ YZ7.1`8
publicvoid setCurrentPage(int currentPage){ z!\*Y
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this.currentPage = currentPage; r|Z{-*`
} 3XKf!P
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/** ipz5 H*
* @return !~Z"9(v'C
* Returns the everyPage. ,//S`j$S
*/ 8EY:tzw
publicint getEveryPage(){ (%9$! v{3
return everyPage; 0 {mex4
} k=^xVQuI
?cZlN!
/** &Qm@9I s
* @param everyPage V6Dbd"
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* The everyPage to set. tp|d*7^i
*/ $Q0n
publicvoid setEveryPage(int everyPage){ 31)&vf[[
this.everyPage = everyPage; P2Y^d#jO
} d5d@k
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/** >sbu<|]a
7
* @return S>{~nOYt-`
* Returns the hasNextPage. rlD8D|ZG
*/ V8(-
publicboolean getHasNextPage(){ pot~<d`:K"
return hasNextPage; ce(#2o&`
} Ca\6vR
N21smC}
/** ;}t(Wnu.
* @param hasNextPage K^[?O{x^B
* The hasNextPage to set. 8>V5dEbx'
*/ Ts9uL5i
publicvoid setHasNextPage(boolean hasNextPage){ I:.s_8mH}
this.hasNextPage = hasNextPage; M3AXe]<eC1
} Pc9H0\+Xk
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/** 0IpmRH/
* @return /tLVX} &
* Returns the hasPrePage. ;rS{:
*/ KlqY@Xt
publicboolean getHasPrePage(){ Js;h%
return hasPrePage; hOeRd#AQK
} pJ{Y
lS{
< vP=zk
/** ?#fQ~ s
* @param hasPrePage .^g p?
* The hasPrePage to set. 'PHl$f*k
*/ &wX]_:?
publicvoid setHasPrePage(boolean hasPrePage){ cnLro
this.hasPrePage = hasPrePage;
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} cNH7C"@GVu
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/** ##{taR8
* @return Returns the totalPage. DI%saw
* r/1(]#kOX
*/ [
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publicint getTotalPage(){ ctUp=po
return totalPage; wS*E(IAl
} Q.[0ct
P* o9a
/** N;gfbh]
* @param totalPage 9B4&m|g
* The totalPage to set. K%d&EYoW]
*/ 0aAoV0fMDz
publicvoid setTotalPage(int totalPage){ 2?x4vI
np;
this.totalPage = totalPage; h$*!8=M
} Ls%MGs9PI
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} u&NV,6Fj2[
*](iS
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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 M_8{]uo
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个PageUtil,负责对Page对象进行构造: |^aKs#va
java代码: ]{iQ21`a-
#*}+J3/
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/*Created on 2005-4-14*/ }'.m*#Y
package org.flyware.util.page; Vc2`b3"Br
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import org.apache.commons.logging.Log; 9gFUaDLo
import org.apache.commons.logging.LogFactory; $?Wb}DU7_L
G2Zer=rC
/** *or(1DXP8
* @author Joa ]oxZ77ciL
* "fI6Cpc
*/ 0mnw{fE8_
publicclass PageUtil { ]!
dTG
/ +\9S
privatestaticfinal Log logger = LogFactory.getLog 6pzSp
s CRdtP
(PageUtil.class); ] @'!lhLi
xUvs:
/** 99S^f:t
* Use the origin page to create a new page dscgj5b1~
* @param page P%6~&woF
* @param totalRecords <m m[S
* @return i$@:@&(~Y
*/ rc{v$.o0
publicstatic Page createPage(Page page, int ""H?gsL[
hj:,S|
totalRecords){ *Uh!>Iv;
return createPage(page.getEveryPage(), RpK@?[4s
g*Phv|kI
page.getCurrentPage(), totalRecords); '7/)Ot(
} y^k$Us
/,dz@
/** 8QK&_n*
* the basic page utils not including exception S:Hl/:iV
Th%zn2R B
handler >V937
* @param everyPage yuVs
YV@"
* @param currentPage GmG5[?)
* @param totalRecords U(Zq= M
* @return page 9z0p5)]n>
*/ Z.WW(C.
publicstatic Page createPage(int everyPage, int S 5U;#H
_&x%^&{
currentPage, int totalRecords){ ;*N5Y}?j'
everyPage = getEveryPage(everyPage); ),)lzN%!
currentPage = getCurrentPage(currentPage); !W\+#ez
int beginIndex = getBeginIndex(everyPage, 7
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cR{#V1Z
currentPage); ~?dI*BZ)]
int totalPage = getTotalPage(everyPage, 5\v3;;A[
CAe!7HiR
totalRecords); z{6Z
11|
boolean hasNextPage = hasNextPage(currentPage, %C0Dw\A*:
N;R^h? '
totalPage); q| 7(
boolean hasPrePage = hasPrePage(currentPage); ==B6qX8T
,I9bNO,%JK
returnnew Page(hasPrePage, hasNextPage, BWNi [^]
everyPage, totalPage, lFkR=!?=
currentPage, 0%B/,/PxD
CAlCDfKW}
beginIndex); us.~G
} +_`7G^U?%
E{\2='3\
privatestaticint getEveryPage(int everyPage){ Y@v>FlqI{
return everyPage == 0 ? 10 : everyPage; K@2),(z
} Fcx&hj1gQ
}qUX=s
GG
privatestaticint getCurrentPage(int currentPage){ NRuNKl.v
return currentPage == 0 ? 1 : currentPage; Fu~j8K
} o4;(Zi#Z
#G3<7PK
privatestaticint getBeginIndex(int everyPage, int |:o4w
Pfh mo $
currentPage){ @ZJS&23E
return(currentPage - 1) * everyPage; YR70BOxK
} Smh,zCc>s
vI?, 47Hj+
privatestaticint getTotalPage(int everyPage, int 7^Uv7<pw
SJLis"8
totalRecords){ >!JS:5|
int totalPage = 0; 3%6?g*
zCA2X
!7F
if(totalRecords % everyPage == 0) [Pp'Ye~K@c
totalPage = totalRecords / everyPage; ^Pf WG*
else
y7{?Ip4[
totalPage = totalRecords / everyPage + 1 ; AX INThJ
]|@^1we
return totalPage; <q836]aaA
} ~Ei<Z`3}7"
+ 3gp%`c4
privatestaticboolean hasPrePage(int currentPage){ =wJX0A|
return currentPage == 1 ? false : true; @WhHUd4s
} =M1I>
{:s f7
privatestaticboolean hasNextPage(int currentPage, qK+5NF|
mq l
Z?-
int totalPage){ Ef\-VKh
return currentPage == totalPage || totalPage == hPh-+Hb
\['Cj*e k
0 ? false : true; nTas~~Q
} # _1`)VS
)BE1Q*=
n
.}t
e>]A*
} v19-./H^
j
Xvv6~
~[ jQ!tz
J,hCvm
#WuBL_nZ~
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。 ?[AD=rUC
Z;i:](
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 \zY!qpX<
> I?IPQB
做法如下: RN1_S
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 7/H)Az@i45
0f/<7R
的信息,和一个结果集List: ;jXgAAz7
java代码: j.Hf/vi`z
D-c4EV
AdEMa}u6
/*Created on 2005-6-13*/ YVU7wW,1
package com.adt.bo; S!UaH>Rh
@- xjfC\d
import java.util.List; bsX[UF
A<{{iBEI`
import org.flyware.util.page.Page; :]KAkhFkbb
CY1Z'
/** uYN`:b8
* @author Joa ]`K2N
*/ WMdg1J+~
publicclass Result { qna8|3eP
\85i+q:LuA
private Page page; TDh5lI
]/Pn
EU[
private List content; +whDU2 "
@5FQX
/** Ytkv!]"
* The default constructor nUO0Ce
*/ CrLrw T
public Result(){ GJrG~T
super(); :>
'+"M2r
} &8H'eAA
t_^4`dW`
/** UNYqft4
* The constructor using fields L,\Iasv
* I,tud!p`
* @param page &Jj<h: *
* @param content @dKTx#gZ
*/ s<Ziegmw|g
public Result(Page page, List content){ +>,I1{u%&
this.page = page; LoV<:|GTI
this.content = content; occ7zcA
} ]Um/FA W
jd:6:Fm
/** 1?}T=)3+$
* @return Returns the content. DQ3<$0
*/ dN q$}
publicList getContent(){ h{Y",7]!
return content; N7"W{"3D
} L0,'mS
2G7Wi!J
/** &d!GImcxQ
* @return Returns the page. >Tgv11[
*/ ll^#JpT[S
public Page getPage(){ 7.Op<
return page; fC`&g~yK'
} 4x34u}l
%J(:ADu]
/** I9Xuok!0>=
* @param content ye&;(30Oq
* The content to set. G{}VPcrbC
*/ @JMiO^
public void setContent(List content){ C+$#y2"z#n
this.content = content; $4LzcwG
} {)XTk&"
79gT+~z
/** N8jIMb'<
* @param page Cdn J&N{
* The page to set. u9e@a9c
*/ K+eM
publicvoid setPage(Page page){ js(pC@<q5
this.page = page; .('SW\u-
} Z@HEj_n
} [txE .7p
j#|ZP-=1_
-@'FW*b
Lbgi7|&
.v
K-LHs
2. 编写业务逻辑接口,并实现它(UserManager, p K*TE5]
1EK*g;H
UserManagerImpl) dO'(2J8
java代码: {: /}NpA$
Txu/{M,
6K^#?Bn;
/*Created on 2005-7-15*/ BPrt'Nc
package com.adt.service; { 6il`>=C
* 4'"2"
import net.sf.hibernate.HibernateException; {7[Ox<Ho
Jy)/%p~
import org.flyware.util.page.Page; O.? JmE
rI\FI0zIp_
import com.adt.bo.Result; {}9a6.V;}
3";q[&F9y
/** 5BIY<B+i
* @author Joa U^PgG|0N
*/ dtDFoETz
publicinterface UserManager { /ZX}Nc g
6ujWNf
public Result listUser(Page page)throws m67V_s,7B
10&8-p1/mc
HibernateException; [^iN}Lz
hrk r'3lv
} wYea\^co
mh%VrAq
z{q`G wW
U{mYTN*:j$
$nb[GV
java代码: UMi~14& ;
W?&%x(6M
tQVVhXQ7
/*Created on 2005-7-15*/ @7}W=HB
package com.adt.service.impl; >P(.:_^p
Uo49*Mr
import java.util.List; ?,/ }`3Vw
(3e2c
import net.sf.hibernate.HibernateException; kJU2C=m@e2
" bG2:
import org.flyware.util.page.Page; u8^lB7!e/
import org.flyware.util.page.PageUtil; `[A];]
*CMx- _
import com.adt.bo.Result; t20K!}D_
import com.adt.dao.UserDAO; btB%[]
import com.adt.exception.ObjectNotFoundException; \U0Q<ot/7
import com.adt.service.UserManager; S:}7q2:
+T ?NH9
/** 'u658Tj
* @author Joa Om&Dw|xG8
*/ /Oono6j
publicclass UserManagerImpl implements UserManager { Ri'n
]~-r}`]
private UserDAO userDAO; @EAbF>>
P>T"cv
/** f$( e\++
* @param userDAO The userDAO to set. ]:;&1h3'7
*/ Gj*9~*xm(
publicvoid setUserDAO(UserDAO userDAO){ %O<BfIZ
this.userDAO = userDAO; x-c"%Z|
} bt *k.=p
ICCc./l|
/* (non-Javadoc) nN;u,}e
* @see com.adt.service.UserManager#listUser zs;JJk^
}JfjX'
(org.flyware.util.page.Page) ?2a $*(
*/ k)u[0}
public Result listUser(Page page)throws =Qq+4F)MD
IV-{ve6
HibernateException, ObjectNotFoundException { 6@f-Glwg
int totalRecords = userDAO.getUserCount(); Vl]>u+YqE
if(totalRecords == 0) :&Nbw
throw new ObjectNotFoundException p_ =z#
G3]4A&h9v~
("userNotExist"); E7hhew
page = PageUtil.createPage(page, totalRecords); rNM;ZPF#
List users = userDAO.getUserByPage(page); Z)!C'c b
returnnew Result(page, users); J4utIGF
} :N@^?q{b
z#N@ 0R
} 3T
9j@N77
^8tEach
C~[,z.FvO
lr?;*f^3
SuznN
L=/$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Cw%{G'O
c,22*.V/
询,接下来编写UserDAO的代码: zi:BF60]=
3. UserDAO 和 UserDAOImpl: 0V]s:S
java代码: l%ZhA=TKQ
J1kM\8%b\
IID5c"
oR
/*Created on 2005-7-15*/ )Z$!PqRw@u
package com.adt.dao; 67TwPvh
+(*DT9s+
import java.util.List; iE{&*.q_}>
_ |p8M!
import org.flyware.util.page.Page; j|n R"!
OSJ$d
import net.sf.hibernate.HibernateException; U.TA^S]`g
Al'3?
/** >7r!~+B"9'
* @author Joa ,[Fb[#Qqb
*/ l,:F
publicinterface UserDAO extends BaseDAO { Q&&@v4L
m*;ERK
publicList getUserByName(String name)throws v:p} B$
g>sSS8RO
HibernateException; z2c6T.1M
z~Q)/d,Ac
publicint getUserCount()throws HibernateException; *A< 5*Db:F
ckn~#UE=
publicList getUserByPage(Page page)throws }Lv;!
9l,oP?
HibernateException; *H122njH+T
F/Pep?'
} _U0f=m
1}37Q&2
M;NX:mX9
6RM/GM
Ie^l~Gb
java代码: f5k6`7Vj]
q=G+Tocv
8f7>?BUS,
/*Created on 2005-7-15*/ |3%8&@ho
package com.adt.dao.impl; ;]fs'LH
C7vxw-o|&p
import java.util.List; !c-*O<Y
fV:83|eQ
import org.flyware.util.page.Page; .o8t+X'G
)i<j XZ:O
import net.sf.hibernate.HibernateException; IAEAhqp
import net.sf.hibernate.Query; nie% eC&U
Wf<LR3
import com.adt.dao.UserDAO; fLVAKn
^GX)Z~
/** DN/YHSYK
* @author Joa a>)f=uS
*/ w:l"\Tm
public class UserDAOImpl extends BaseDAOHibernateImpl W`&hp6Jq
\f)#>+X-
implements UserDAO { 6,uX,X5
?8 {"x8W;
/* (non-Javadoc) <X5fUU"+U
* @see com.adt.dao.UserDAO#getUserByName 4sM.C9W
h1{3njdr
(java.lang.String) ~v83pu1!2s
*/ kR9-8I{J
publicList getUserByName(String name)throws 0Qd:`HF[
>{Tm##@,k
HibernateException { )jC%a6G!
String querySentence = "FROM user in class Ha#>G<;n
[r-p]"R
com.adt.po.User WHERE user.name=:name"; 1sCR4L:+
Query query = getSession().createQuery <ih[TtZ
-![|}pX
(querySentence); +*^H#|!
query.setParameter("name", name); }-fl$j?9E
return query.list(); " Jr-J#gg
} &[SC|=U'M
kN>!2UfNS
/* (non-Javadoc) `"~%bS
* @see com.adt.dao.UserDAO#getUserCount() QM]YJr3rE
*/ @P"p+
publicint getUserCount()throws HibernateException { G\?YK.Y>
int count = 0; "]iB6
String querySentence = "SELECT count(*) FROM B?qjkP
:L;a:xSpn=
user in class com.adt.po.User"; "\=U)CJ
Query query = getSession().createQuery "vGW2~*)
D-4f.Tq4#
(querySentence); JLi|Td"1%
count = ((Integer)query.iterate().next ty`DJO=Omj
CP{cAzHO
()).intValue(); @I*{f
return count; bF(f*u
} 03(4 x'z
\4#W xZ
/* (non-Javadoc) E P+J
N
* @see com.adt.dao.UserDAO#getUserByPage Lp7SLkwh3M
m`_ONm'T&
(org.flyware.util.page.Page) 4aY|TN/|
*/ d/Q%IeEL.
publicList getUserByPage(Page page)throws )ANmIwmC#
[9 RR8
HibernateException { EZj9wd"u
String querySentence = "FROM user in class 3Y~>qGQwh
9K&:V(gmw
com.adt.po.User"; h}EPnC}
Query query = getSession().createQuery rbCAnwA2
7yba04D)
(querySentence); Lxk[;j+
query.setFirstResult(page.getBeginIndex()) o lxByzTh>
.setMaxResults(page.getEveryPage()); O<\@~U
return query.list(); j)GtEP<n#
} BSMwdr
V_:&S2j
} :h V7>
rr
S@Hf
&hJ
|W\(kb+
`#gie$B{
<o= 8FO
至此,一个完整的分页程序完成。前台的只需要调用 veRm2LSP
h-D}'R
userManager.listUser(page)即可得到一个Page对象和结果集对象 +U.I( 83F
7!$^r$t
的综合体,而传入的参数page对象则可以由前台传入,如果用 -tNUMi'
!YJs]_Wr
webwork,甚至可以直接在配置文件中指定。 T n}s*<=V
|&[EZ+[
下面给出一个webwork调用示例: 6 _ow%Rx~F
java代码: =>dGL|
<rmvcim{*
lA-h`rl/
/*Created on 2005-6-17*/ l0hlM#
package com.adt.action.user; _7)n(1h[3b
->{KVPHe{
import java.util.List; +H2-ZXr
3Le{\}-$.
import org.apache.commons.logging.Log; XGMiW0j0B
import org.apache.commons.logging.LogFactory; M|[o aanY'
import org.flyware.util.page.Page; f4Rf?w*
p[lA\@l[
import com.adt.bo.Result; :Lug7bUVD
import com.adt.service.UserService;
JSg$wi8
import com.opensymphony.xwork.Action; Y)a^(!<H<
_]*>*XfF(
/** vA.MRu#
* @author Joa Zr,VR-kW+
*/ +&"zU GTIc
publicclass ListUser implementsAction{ }-3mPy(*%
Uv~QUL3>
privatestaticfinal Log logger = LogFactory.getLog T"}vAG( .O
^<-+@v*
(ListUser.class); zNuJj L
t!\tF[9e
private UserService userService; XF_pN[}
lUiL\~Gq
private Page page; /[>sf[X\I9
[ps*uva
privateList users; N{~YJ$!8
BI}Cg{^km
/* 3 SGDy]
* (non-Javadoc) m<g~H4
* {$Gd2gO
* @see com.opensymphony.xwork.Action#execute() c:u5\&~{
*/ uL/m u<
publicString execute()throwsException{ Ji 0
tQV
Result result = userService.listUser(page); FjI`uP
page = result.getPage(); 1~QPG\cdIX
users = result.getContent(); .q 3/_*
return SUCCESS; wuJ4kW$
} ;{o|9x|
q8Z<{#oXu
/** +XYE {E5
* @return Returns the page. ")HFYqP>9
*/ ~<OSYb
public Page getPage(){ L`EBfz\n
return page; )Iq <+IJ
} :Qf '2.h)
f.`*Qg L
/** Nm>A'bLM
* @return Returns the users. Mzw X>3x
*/ H ?y,ie#u
publicList getUsers(){ 5RpjN: 3
return users; _Z,\Vw:\F
} ;
p {[1
xLZG:^(I
/** a"g!e^
* @param page *%t^;&x?
* The page to set. M>8A\;"
*/ %\Mo-Ow!\
publicvoid setPage(Page page){ 6;qy#\}2
this.page = page; r s?R:+
} Ktm4 A O
0|\$Vp
/** Uwx
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* @param users Y0K[Sm>
* The users to set. 1,!(0
5H
*/ W#C*5@ 8
publicvoid setUsers(List users){ XJ5.
this.users = users; rkY[E(SY
} A;|D:;x3G
%zw1}|s#z
/** >q1L2',pK
* @param userService ZH)="qx[
* The userService to set. &&RimoIeo
*/ 0f>5(ek
publicvoid setUserService(UserService userService){ }HePZ{PLM
this.userService = userService; +|89>}w4
} KX7>^Bt&k
} 6,9>g0y'NG
hJ#xB6
D^3vr2
e?ly H
r7,t";?>
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, z4]api(xZ
Eq\M;aDq
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 QM#4uI55B
K$_0`>[
么只需要: aC.~&MxFC
java代码: 9dUravC7
:#?5X|Gz
J9iy
<?xml version="1.0"?> j578)!aJ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork >!1.
Jrpx}2'9:a
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 25[I=ZdS
MsGM5(r:b
1.0.dtd"> C"T;Qp~B
Nyj( 0W
<xwork> H_X [t* 2
w{@ o^rs
<package name="user" extends="webwork- %k?U9pj^
;Q*or2"!
interceptors"> 2M'[,Xe
A/KJqiag
<!-- The default interceptor stack name qC:raH_:
QTXt8I
--> \\dMy9M-
<default-interceptor-ref | Aw%zw1@
Qq;Foa
name="myDefaultWebStack"/> scou%K
$!yW_HTx
<action name="listUser" 1@1U/ss1
=i*;VFc
class="com.adt.action.user.ListUser"> ]4]6Qki
<param XkF%.hWo
c+$*$|t=v`
name="page.everyPage">10</param> C$D-Pt"+
<result ?9\EN|O^
tL)t" i
name="success">/user/user_list.jsp</result> 2Kyl/C,
</action> q$tUH)0
9"A`sGZ
</package> =~H<Z LE+
9:1Q1,-i!-
</xwork> ,N[7/kT|
_i|t
Y4L
3ojlB |Z
% <*g!y `
Y>G@0r BG
,TN
2
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 w6GyBo{2O_
SO(NVJh
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 _FVcx7l!u
v+`N*\J_
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 pDIVZC
u TK,&
k+C zj
8b-Q F
A?%H=>v$
我写的一个用于分页的类,用了泛型了,hoho r)~ T@'y
Vq\`+&A
java代码: S` ;?z
X/2&!O
>eB\(EP
package com.intokr.util; \$\ENQ;Nk
"*5hiTr8+
import java.util.List; dA0.v+Foz"
@EpIh&
/** X+S9{X#Cm
* 用于分页的类<br> O_DtvjI'
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 6%Pdy$ P
* Vz~nT
* @version 0.01 (Cd\G=PK
* @author cheng J/GSceHF
*/ $[&*Bj11Yg
public class Paginator<E> { G<f@#[$'
privateint count = 0; // 总记录数 5Z\#0":e
privateint p = 1; // 页编号 ws|;`
privateint num = 20; // 每页的记录数 L>%o[tS
privateList<E> results = null; // 结果 e5B Qr$j
~ga`\%J
/** TXk?#G\o
* 结果总数 I`LuRlw
*/ $!(pF
publicint getCount(){ $lIz{ySJv
return count; lBTmx(_}}r
} 7:3$Ey
*
%M3PTY\
publicvoid setCount(int count){ (?{MEwHG
this.count = count; Q[I=T&
} j|%HIF25
U,q\emR
/** 7C ,UDp|
* 本结果所在的页码,从1开始 .wu
xoq
* \":m!K;Z
* @return Returns the pageNo. ;u(<h?%e
*/ M8Z2Pg\0
publicint getP(){ "WK{ >T
return p; ? 1$fJ3
} $UCAhG$
\lC
/** d'$T4yA
* if(p<=0) p=1 Z->p1xkX
* :^x?2%
~K.
* @param p C
#6dC0
*/ Dzs[GAQ]
publicvoid setP(int p){ YY!6/5*/]
if(p <= 0) \y)
p = 1; J@X'PG<
6B
this.p = p; ";Rtiiu
} $8[r9L!
!PJ 6%"
/** 78OIUNm`
* 每页记录数量 ct,l^|0Hu8
*/ W.0L:3<"
publicint getNum(){ Ii_ojQP-z
return num; 88h3|'*
} ),!;| bh
F[[TWf/
/** 5~WGZc
* if(num<1) num=1 u[/m|z
*/ q]N:Tpm9
publicvoid setNum(int num){ D{4YxR
PX
if(num < 1) i21Gw41p:
num = 1; +d!v}aJ
this.num = num; %\r!7@Q
} .h5[Q/*h
.]7Qu;L
/** H0SQ"?
* 获得总页数 ? Cg>h
*/ pL%r,Y_^\x
publicint getPageNum(){ {=-\|(Bx
return(count - 1) / num + 1; uDSxTz{
} wqW0v\
*b}lF4O?
/** L^4-5`gj
* 获得本页的开始编号,为 (p-1)*num+1 $N=N(^
*/ ;cz|ss=
publicint getStart(){ B7<Kc
return(p - 1) * num + 1; Ch%m
} -O!Zxg5x
y>|{YWbp?
/**
\qR %%S
* @return Returns the results. ADk8{L{UU
*/ H0R&2#YD
publicList<E> getResults(){ aKJQm'9Ks
return results; R%
,<\d7
} ZwerDkd
NDAw{[.%
public void setResults(List<E> results){ #\ n8M
this.results = results; 0#*#a13
} ]
0m&(9
,qrQ"r9
public String toString(){ GSQ/NYK
StringBuilder buff = new StringBuilder u% n*gcY
b-*3 2Y%
(); ^ Dt#$Z
buff.append("{"); lmSo8/%T
buff.append("count:").append(count); =)`
p_W
buff.append(",p:").append(p); t2iv(swTe
buff.append(",nump:").append(num); ~~,rp) )
buff.append(",results:").append yxq}QSb \3
`VL}.h
(results); #I3$3^0i#
buff.append("}"); S#Sb ]
return buff.toString(); MqA`yvQm
} &0 BdUU+:<
y&= ALx@
} ?k|H3;\
=.`qixN
%-AE]-/HI