Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 *FJZiPy
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &Ni`e<mP
@UdfAyL
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 [=|jZVhT
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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 m:hY`[ f6
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分页支持类: pn*3\
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java代码: Sv;_HZ
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package com.javaeye.common.util; |{@FMxn|q
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import java.util.List; O=9-Qv|
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publicclass PaginationSupport { pc?>cs8
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publicfinalstaticint PAGESIZE = 30; 4BwQA#zE
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privateint pageSize = PAGESIZE; MJ=)v]a
WlYs~(=9
privateList items; CwJDmz\tk
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privateint totalCount; R-:fd!3oQ
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privateint[] indexes = newint[0]; RNQK
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privateint startIndex = 0; !'Q -yoHKD
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public PaginationSupport(List items, int .Udj@{
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totalCount){ $fgf
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setPageSize(PAGESIZE); #);[mW{F
setTotalCount(totalCount); &[hLzlrg
setItems(items); vp(;W,ba:|
setStartIndex(0); #b7$TV
} wR{'y)$
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public PaginationSupport(List items, int V
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totalCount, int startIndex){ (
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setPageSize(PAGESIZE); &5L<i3BX
setTotalCount(totalCount); cv/_r#vN
setItems(items); b}Zd)2G
setStartIndex(startIndex); ".dZn6"mI
} :eZh'-c?
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public PaginationSupport(List items, int *:O.97q@h
G"T',~
totalCount, int pageSize, int startIndex){ Z;h<6[(
setPageSize(pageSize); A*|cdY]HP
setTotalCount(totalCount); X=C1/4wU
setItems(items); &[&r2>a
setStartIndex(startIndex); 0 u?{\
} uf&N[M
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publicList getItems(){ KzQ3.)/q
return items; 3~#h|?
} = P
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publicvoid setItems(List items){ TT9z_Q5~
this.items = items; {-A^g!jT&
} |+$%kJR=
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publicint getPageSize(){ )z8!f}:De=
return pageSize; %0Y=WYUH>
} cJgBI(S5
,TRTRb;
publicvoid setPageSize(int pageSize){ $#|gLVOQ
this.pageSize = pageSize; .%zy`n
} GQ_p-/p
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publicint getTotalCount(){ 0<TD/1wN
return totalCount; GHQ;hN:
} kPjd_8z2n
QORN9SY
publicvoid setTotalCount(int totalCount){ r_YIpnJ
if(totalCount > 0){ 7#<c>~
this.totalCount = totalCount; w{dIFvQ"$
int count = totalCount / +w8R!jdA
rDdzxrKg{
pageSize; E\u#t$
if(totalCount % pageSize > 0) .`CZUKG
count++; R<x'l=,D(
indexes = newint[count]; e:AHVepj{
for(int i = 0; i < count; i++){ {s3z"OV
indexes = pageSize * CDi<<,
*UW=Mdt
i; S60IPya
} ?6!]Nl1gr
}else{ dSCzx
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this.totalCount = 0; }oJAB1'k
} MV=9!{`
} {_U
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publicint[] getIndexes(){ it2 a
return indexes; rfw-^`&{
} tb?YLxMV
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publicvoid setIndexes(int[] indexes){ G4
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this.indexes = indexes; U=8@@yE
} i*eAdIi
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publicint getStartIndex(){ )fdE6
return startIndex; VGqa)ri"
} 0hZ1rqq8C
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publicvoid setStartIndex(int startIndex){ _73h<|0
if(totalCount <= 0) `c+/q2M
this.startIndex = 0; Y
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elseif(startIndex >= totalCount) eh R{X7J
this.startIndex = indexes A>VX*xd
*4|Hqa
[indexes.length - 1]; -|Kzo_"
v5
elseif(startIndex < 0) 8q)=
this.startIndex = 0; -A-tuyIsh"
else{ ?GBkqQ
this.startIndex = indexes Z2"?&pKV
hO[3 Z^X
[startIndex / pageSize]; 6x=YQwn~
} a ,7&"
} @/UfDye
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publicint getNextIndex(){ x7T+>
int nextIndex = getStartIndex() + 6Fy@s
s/Xb^XjS1
pageSize; [Vdz^_@Y
if(nextIndex >= totalCount) 1nPZ<^A&@
return getStartIndex(); w{ `|N$
else #0;HOeIiH
return nextIndex; j8 C8X$
} n-QJ;37\
0|D&"/.R#!
publicint getPreviousIndex(){ V[a[i>,Z
int previousIndex = getStartIndex() - 2AVc?
9@
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pageSize; &Np9kIMCB
if(previousIndex < 0) @/%{15s.
return0; vw<K}z
else ]IJv-(
return previousIndex; mDFlz1J,e
} 2=ztKfsBhE
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} +\# Fd
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抽象业务类 T}7uew\v0<
java代码: j[6Raf/(n
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/** p$;I'
* Created on 2005-7-12 FbACTeB
*/ A<YsfDa_d
package com.javaeye.common.business; jw6Tj;c
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import java.io.Serializable; u1K\@jlw
import java.util.List; NE|[o0On
0=v{RQ;W4
import org.hibernate.Criteria; *Dr5O 9Y
import org.hibernate.HibernateException; )y7_qxwbV
import org.hibernate.Session; em2_pq9q
import org.hibernate.criterion.DetachedCriteria; M,:Bl}
import org.hibernate.criterion.Projections; d`Q7"}uZ
import wb"RB
A9
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org.springframework.orm.hibernate3.HibernateCallback; f"&Xr!b.h
import /&ygi H{^
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org.springframework.orm.hibernate3.support.HibernateDaoS 0'$p$K
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upport; #p
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import com.javaeye.common.util.PaginationSupport; 9>,Qgp,w
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public abstract class AbstractManager extends &d`^E6#
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HibernateDaoSupport { N~,_`=yRx
<M[U#Q~?~e
privateboolean cacheQueries = false; $M"0BZQ?y!
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privateString queryCacheRegion; L&Qi@D0P
6!EYrX}rI[
publicvoid setCacheQueries(boolean G5]1s
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cacheQueries){ {,O`rW_eS
this.cacheQueries = cacheQueries; aw}+'(?8]
} \Rk$t7ZH
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publicvoid setQueryCacheRegion(String fAj2LAK
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queryCacheRegion){ M:ai<TZ]
this.queryCacheRegion = m$y]Lf
p {%t q$}.
queryCacheRegion; F'J [y"~_
} n+2J Dq|?p
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publicvoid save(finalObject entity){ K}I0o!(#
getHibernateTemplate().save(entity); ]T{E
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} ]" x\=A
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publicvoid persist(finalObject entity){ !}&"W,,0
getHibernateTemplate().save(entity); :7;[`bm(G
} +AQDD4bu
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publicvoid update(finalObject entity){ WBppKj_M
getHibernateTemplate().update(entity); 5)lW
} RSWcaATZN
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publicvoid delete(finalObject entity){ !jh%}JJ
getHibernateTemplate().delete(entity); 5A_4\YpDR
} `n-vjjG%#
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publicObject load(finalClass entity, -Fwh3F4g
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finalSerializable id){ 6`puTL?
return getHibernateTemplate().load + Oobb-v
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(entity, id);
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} P%o44|[][
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publicObject get(finalClass entity, U|fTb0fB
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finalSerializable id){
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return getHibernateTemplate().get g_D-(J`IK,
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(entity, id); A_r<QYq0|
} StM/
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publicList findAll(finalClass entity){ PvOC5b
return getHibernateTemplate().find("from P%GkcV
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" + entity.getName()); mCb 9*|
} 0o68rF5^s
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publicList findByNamedQuery(finalString Lbq_~
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namedQuery){ x1DVD!0 ~{
return getHibernateTemplate +Hyk'=.W
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().findByNamedQuery(namedQuery); Hhf72IX
} Wu{&;$
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publicList findByNamedQuery(finalString query, dF2@q@\.+
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finalObject parameter){ <3#<I)#
return getHibernateTemplate 7s]Wq6
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().findByNamedQuery(query, parameter); UA0tFeH
} 2NR7V*A
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publicList findByNamedQuery(finalString query, LkaG[^tfN
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finalObject[] parameters){ z_(eQP])
return getHibernateTemplate 1jOKcm'#
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().findByNamedQuery(query, parameters); 9qeZb%r&
} "8t\MKt(
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publicList find(finalString query){ 6e:P.HqjA
return getHibernateTemplate().find |F~88j{VN
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(query); +wts 7,3
} eYDgEM
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publicList find(finalString query, finalObject BQU/Qo DY
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parameter){ }@*I+\W/
return getHibernateTemplate().find pU DO7Q]
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(query, parameter); UG=I~{L
} <rMv0y+r
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public PaginationSupport findPageByCriteria 8}K"IW
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(final DetachedCriteria detachedCriteria){ 4f
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return findPageByCriteria K!7q!%Ju
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); SauHFl8?
} zkG>u,B}
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public PaginationSupport findPageByCriteria GRQ_+K
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(final DetachedCriteria detachedCriteria, finalint |Pf(J;'[
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startIndex){ THr8o V5
return findPageByCriteria c'~[!,[b<
Ut':$l=
(detachedCriteria, PaginationSupport.PAGESIZE, :Fo4O'UC
Uir*%*4:
startIndex); 0k.v0a7%
} aYBTrOd z
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public PaginationSupport findPageByCriteria Rd vn)K
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(final DetachedCriteria detachedCriteria, finalint wVQdUtmk
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pageSize, x i.IRAZX
finalint startIndex){ a G@nErdW
return(PaginationSupport) yYB NH1
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getHibernateTemplate().execute(new HibernateCallback(){ +0U#.|?
publicObject doInHibernate 'FqEB]gu
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(Session session)throws HibernateException { fK);!Hh
Criteria criteria = w=5
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detachedCriteria.getExecutableCriteria(session); zw<
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int totalCount = BMY>a
u'=(&><
((Integer) criteria.setProjection(Projections.rowCount TIETj~+
0 S2v"(_T
()).uniqueResult()).intValue(); >KKeV(Ur
criteria.setProjection )]tvwEo
{Evcc+Eq
(null); Z/n3aYM
List items =
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quY "
criteria.setFirstResult(startIndex).setMaxResults htV#5SUx&
]2LXUYB
(pageSize).list(); FQ0KUb}0
PaginationSupport ps = d4% `e&K]'
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new PaginationSupport(items, totalCount, pageSize, b h*^{
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startIndex); xl3zy~;M
return ps; / =-6:L
} V0s,f.a
}, true); 8s~\iuk
} Q%I#{+OT
.<HC[ls
public List findAllByCriteria(final 487YaioB$
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DetachedCriteria detachedCriteria){ "bPCOJ[v9
return(List) getHibernateTemplate XzW7eO,A
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().execute(new HibernateCallback(){ =?HzNA$yh
publicObject doInHibernate &;Ed*OJ
J"5jy$30'$
(Session session)throws HibernateException { =w?M_[&K)
Criteria criteria = ^l--zzO8l
xv^Sh}\}
detachedCriteria.getExecutableCriteria(session); W"dU1]
return criteria.list(); pXve02b1B
} G
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}, true); TNJ<!6
} uC- A43utv
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public int getCountByCriteria(final ix^gAot
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DetachedCriteria detachedCriteria){ QH4k!^
Integer count = (Integer) TeKC} NW
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getHibernateTemplate().execute(new HibernateCallback(){ 5dqQws-,?1
publicObject doInHibernate 7Pwg+|
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(Session session)throws HibernateException { Q! Kn|mnN
Criteria criteria = kkT3wP
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detachedCriteria.getExecutableCriteria(session); 3R'.}^RN
return B*y;>q "{U
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criteria.setProjection(Projections.rowCount 0{-`Th+h
"\4]X"3<+
()).uniqueResult(); `'kc|!%MUq
} mm_^gQ,`
}, true); C/CN
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return count.intValue(); kxygf9I!;
} qx Wgt(Os
} IY V-*/
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用户在web层构造查询条件detachedCriteria,和可选的 mPckf
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 ;0;3BH A
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PaginationSupport的实例ps。 ~l(G6/R
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ps.getItems()得到已分页好的结果集 $<
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ps.getIndexes()得到分页索引的数组 ftO+.-sm<
ps.getTotalCount()得到总结果数 {-o7w0d_
ps.getStartIndex()当前分页索引 D}mo\
ps.getNextIndex()下一页索引 F='Xj@&O
ps.getPreviousIndex()上一页索引 CKx\V+\O
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F# jCEq
y=-{Q
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 B"7$!C o
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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 `x2fp6
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一下代码重构了。 J'|=*#
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我把原本我的做法也提供出来供大家讨论吧: B1x'5S;Bq
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首先,为了实现分页查询,我封装了一个Page类: tU9rCL:P
java代码: /uC+.B9k
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/*Created on 2005-4-14*/ nwY2BIB
package org.flyware.util.page; NnJ>0|74g
UN,<6D3\b
/** imo'(j7
* @author Joa YnKFcEJrT
* uOyLC<I/
*/ )3k)2X F
publicclass Page { p#ZMABlE,P
'
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/** imply if the page has previous page */ lf?Z{^
privateboolean hasPrePage; TjKzBAX
[P.@1mV
/** imply if the page has next page */
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privateboolean hasNextPage; 29R_n)ne
+#|'|}j
/** the number of every page */ ;6DR.2}?>
privateint everyPage; M/n[&
~z\pI|DQ
/** the total page number */ L@C >-F|p
privateint totalPage; #cw!
&
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/** the number of current page */ @).WIs
privateint currentPage; JA}S{
y&n1 Nj]^
/** the begin index of the records by the current sL!;hKK
Nb#H@zm
query */ ODM>Z8@W/
privateint beginIndex; 9)G:::8u7
,$hQ(yF
SlH7-"Ag
/** The default constructor */ G/x3wR
public Page(){ bl(BA}<
@"q~AY
} c28oLT1|D
PiIp<fJd$
/** construct the page by everyPage ^U0apI
* @param everyPage yC9:sQ'k
* */ D]t~S1ycG7
public Page(int everyPage){ t:?<0yfp&
this.everyPage = everyPage; B|$\/xO
} H @3$1h&YS
!1ie:z>s
/** The whole constructor */ d+gk q\
public Page(boolean hasPrePage, boolean hasNextPage, OGSEvfW
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m
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int everyPage, int totalPage, |_Naun=+~
int currentPage, int beginIndex){ 9b{g+lMZo
this.hasPrePage = hasPrePage; n r'YWW
this.hasNextPage = hasNextPage; |YG)NO
this.everyPage = everyPage; rXHHD#\oF
this.totalPage = totalPage; X+(aQ
>y
this.currentPage = currentPage; S&4w`hdD>~
this.beginIndex = beginIndex; Sa?~t3*H
} rwi2kk#@P
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/** LM'*OtpDG
* @return $5 q{vy
* Returns the beginIndex. c]cO[T_gGa
*/ J@u!S~&r
publicint getBeginIndex(){ S>/I?(J
return beginIndex; +1JZB*W
} =$:4v`W0(
Ymrpf
/** n:}MULy;
* @param beginIndex [ *mCa:^
* The beginIndex to set. rsIt~w
*/ "K4X:|Om"
publicvoid setBeginIndex(int beginIndex){ S 2{ ?W
this.beginIndex = beginIndex; BDB zc5Q(
} K8 Kz
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/** K'{ wncumQ
* @return MJ*oeI!.=
* Returns the currentPage. n@yd{Rc
*/ 9M-NItFos
publicint getCurrentPage(){ ,M+h9_&0?
return currentPage; S7\|/h:4
} nU">> 1!U
d-A%ZAkE]
/** AW{/k'%xw
* @param currentPage `Tm8TZd66
* The currentPage to set. tyGnG0GK
*/ ^{6UAT~!R
publicvoid setCurrentPage(int currentPage){ l*m]2"n]
this.currentPage = currentPage; sKE*AGFLd
} *y[~kWI
H)?" 8 s
/** ]0/~6f
* @return +Qb2LR
* Returns the everyPage. ]UpHD.Of[t
*/ 4n.i<K8K[
publicint getEveryPage(){ lHj7O&+
return everyPage; 'nmYB:&!
} G`3vH,
#h5Hi9LKf
/** LcQ\?]w`]
* @param everyPage {?h6*>-^Z
* The everyPage to set. Z{R=h7P
*/
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publicvoid setEveryPage(int everyPage){ tM?I()Y&P
this.everyPage = everyPage; FdK R{dX}
} :,J86#S)
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/** w~FO:/
* @return 9N3oVHc?
* Returns the hasNextPage. .Q6{$Y%l
*/ '!|E+P-
publicboolean getHasNextPage(){ ht[TMdV
return hasNextPage; ,_X,V!
} \gPNHL*
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/** b}q(YgH<
* @param hasNextPage 0I AaPz/e
* The hasNextPage to set. (WU~e!}
*/ p%M(G#gOgP
publicvoid setHasNextPage(boolean hasNextPage){ zs]>XO~Jg
this.hasNextPage = hasNextPage; 0UAr}H.:
} qLktMp_
5xn0U5U
/** /[)P^L`
* @return b^=8%~?%4
* Returns the hasPrePage. k Y |=a
*/ >5z`SZf
publicboolean getHasPrePage(){ HN&vk/[
return hasPrePage; X|QX1dl
} w|U@jr*H]
TJGKQyG$L
/** tX2>a
* @param hasPrePage J~ gkGso
* The hasPrePage to set. |GLn
9vw7S
*/ eB1eUK>
publicvoid setHasPrePage(boolean hasPrePage){ HpgN$$\@
this.hasPrePage = hasPrePage; !C)>
} =<tJAoVV
rq|czQ
/** TY{?4
* @return Returns the totalPage. t+Tg@~K2[>
* u[% J#S
*/ 6T'43h. :
publicint getTotalPage(){ 3By>t!~Q
return totalPage; "9Fv!*<-W
} E4fvYV_ra
vXWESy
/** Dqo:X`<bT
* @param totalPage ;U:o'9^9T
* The totalPage to set. zYl+BM-j,6
*/ w}KcLaI
publicvoid setTotalPage(int totalPage){ z%-"'Y]
this.totalPage = totalPage; 1PjX:]:
} XS~w_J#q
j?` D\LZhf
} ?9.? w-Q'
@X / =.
:$@zX]?M
Y~\xWYR
Y(;[L`"
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 KgkB)1s@n
LSOwa
个PageUtil,负责对Page对象进行构造: 3 mMdq*X5
java代码: a*ixs'MJ
O8}s*} ]
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/*Created on 2005-4-14*/ }lbx
package org.flyware.util.page; &[\arwe)
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import org.apache.commons.logging.Log; Fu=VY{U4
import org.apache.commons.logging.LogFactory; E52:c]<'m
ZCq\Zk1O&
/** J'&?=|
* @author Joa )pj \b[
* \>CBam8d
*/ wB0WR
publicclass PageUtil { ^{,},
i
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privatestaticfinal Log logger = LogFactory.getLog tj Bv{
e}@J?tJK.L
(PageUtil.class); h-u*~5dB<&
=>TtX@ Q{
/** ]$X=~>w
* Use the origin page to create a new page .
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* @param page bJu,R-f
* @param totalRecords TuPxyB
* @return u(Q(UuI
*/ ).6/ii9gt
publicstatic Page createPage(Page page, int l@2`f#y1~<
lJp v
totalRecords){ 7VD7di=D
return createPage(page.getEveryPage(), +.Ukzu~s
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page.getCurrentPage(), totalRecords); m<;" 1<k
} o`]FH_
+Gs;3jC^
/** m^&mCo,
* the basic page utils not including exception *^m.V=
Gf$>!zXr
handler B,qZwc|
* @param everyPage yD'h5)yu
* @param currentPage &~6O;}\
* @param totalRecords E&=?\KM
* @return page y")>"8H
*/ G&B}jj
publicstatic Page createPage(int everyPage, int y3$\ m
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currentPage, int totalRecords){ `9)2nkJk'z
everyPage = getEveryPage(everyPage);
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currentPage = getCurrentPage(currentPage); eHZl-|-
int beginIndex = getBeginIndex(everyPage, ;(Va_
w9}IM149
currentPage); F>nrV
int totalPage = getTotalPage(everyPage, 3m9E2R,
B}bNl 7
~
totalRecords); Cd*C^cJU&z
boolean hasNextPage = hasNextPage(currentPage, :Gk~FRA|
|iThgq_\z
totalPage); f\_Q+!^
boolean hasPrePage = hasPrePage(currentPage); y(g
Otg
-Q8`p
returnnew Page(hasPrePage, hasNextPage, ))zaL2UP.
everyPage, totalPage, `t"Kq+
currentPage, &cejy>K
?n~j2-[<
beginIndex); 6@361f[
} ~H."{
5q*~h4=r7
privatestaticint getEveryPage(int everyPage){ 7q=xW6
return everyPage == 0 ? 10 : everyPage; |#,W3Ik(l
} )W#g@V)>
p5w g+K
privatestaticint getCurrentPage(int currentPage){ 4&WzGnK
return currentPage == 0 ? 1 : currentPage; _Xe< JJvq
} ^W*)3;5
FX%E7H
privatestaticint getBeginIndex(int everyPage, int :jCaDhK
JG$J,!.\
currentPage){ vIv3rN=5vB
return(currentPage - 1) * everyPage; rI$10R$+H
} /v<8x?=
2,`mNjHh
privatestaticint getTotalPage(int everyPage, int ,o6: V]a
7hE=+V8
totalRecords){ Jk{2!uP
int totalPage = 0; 5Uz(Bi
Qc/J"<Lx
if(totalRecords % everyPage == 0) +#9 (T
totalPage = totalRecords / everyPage; LLN^^>5|l
else msJn;(Pn
totalPage = totalRecords / everyPage + 1 ; ioQlC4Y
!I$RE?7eY
return totalPage; Sv",E@!f
} At:C4>HE@
Ee| y[y,
privatestaticboolean hasPrePage(int currentPage){ 1z!Lk*C)
return currentPage == 1 ? false : true; %8}w!2D S
} <FLc0s
$9$NX/P
privatestaticboolean hasNextPage(int currentPage, gW%(_H mX
a2n#T,kq&
int totalPage){ EPfVS
return currentPage == totalPage || totalPage == ,\"gN5[$(
/d;l:
0 ? false : true; =-Tetp
} n\,W:G9AR7
X ^)5O>>|t
,bg#pG!x Q
} oZw#Nd
-': tpJk
QJ'C?hn
-hfY:W`Dz
NyNu1V$
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。 }x-8@9S~z
L@uKE jR
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 xEqrs6sR
eZo%q,L
做法如下: ObnB6ShKi
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )HcC\[
b9jm=U
的信息,和一个结果集List: wVX0!y6
java代码: ^|z>NV5>
v.J#d>tvf
~KvCb3~X
/*Created on 2005-6-13*/ $'w l{D"
package com.adt.bo; 7 |A,GH
ponvi42u
import java.util.List; (d\bSo$]
Vh&KfYY
import org.flyware.util.page.Page; Qmn5-yiw1d
>Li?@+Zl
/** -tJ*F!w6U
* @author Joa GW#Wy=(_
*/ UNae&Zir
publicclass Result { 2sH5<5G'
.`9KB3
private Page page; Mf"B!WU>]B
G@2M&0'
private List content; (w fZ!
=X B)sC%
/** ce\-oT
* The default constructor I_Qnq4Sk(
*/ I
Cs1=
public Result(){ vhW'2<(
super(); ?*0kQo'
} 7y3; F7V
9yPB)&"EF
/** =T`-h"E~@
* The constructor using fields *bK@ A2`
* ,#6\:i
* @param page /zM7G?y
* @param content 0v?,:]A0E
*/ ,v+SD\7|
public Result(Page page, List content){ gf@Dy6<
this.page = page; {cFei3'q
this.content = content; dLq!t@?iu>
} -1:asM7
W\ckt]'
/** /r6DPR0\
* @return Returns the content. D.~t#a A
*/ &R]G)f#w%*
publicList getContent(){ g&
Rk}/F
return content; fi)ypv*
} $Z4p$o
dk
hkY E7
/**
/uWON4
* @return Returns the page. YL+W4ld
*/ RPu-E9g@
public Page getPage(){ `:&{/|uP7
return page; -p }]r
} '1+ Bgf
(46)v'?
/** bPEAG=l "-
* @param content p#w,+)1!d
* The content to set. "x)W3C%*S
*/ $A,=z
public void setContent(List content){ U+z&jdnhDR
this.content = content; Wil+"[Ge
} 2= _.K(
#"|Ey6&
/** cVMTT]cj1
* @param page ~H.;pJ{ 8
* The page to set. \a#2Wm
*/ %AFy{l
publicvoid setPage(Page page){ R?(j#bk
this.page = page; GUxhCoxb
} 6ZE]7~X
} N78Ev7PN
)L?Tq"hy
Z=xrjE
|[ge,MO:
c=5$bo]LI
2. 编写业务逻辑接口,并实现它(UserManager, C,E 5/XW
AG?oA328
UserManagerImpl) 31}6dg8?n
java代码: _Cxs"to
anbr3L[!
ZO,]h9?4
/*Created on 2005-7-15*/ _Cs.%R!r
package com.adt.service; +hfl.OBy
;O CYx[|
import net.sf.hibernate.HibernateException; G8SJ<\?
p=zjJ~DVd
import org.flyware.util.page.Page; pd|s7
y~\z_') <>
import com.adt.bo.Result; h(9K7
pJmn;XbME
/** \%)p7PNY
* @author Joa ojaZC,}
*/ B\Uj
publicinterface UserManager { w/UsEIr
+mY(6|1
public Result listUser(Page page)throws p(Sfw>t(
lr1i DwZV
HibernateException; [W2k#-%G
UwLa9Dn^
} ;3w W)gL1
yk=H@`~!
/q=<OEC
^71sIf;+
qU"+0t4
java代码: d-Sm<XHu.
j8lbn |.
js{ RaR=
/*Created on 2005-7-15*/ ]!/1qF
package com.adt.service.impl; (qaY,>je]D
fE(rDQI
import java.util.List; ,QK>e;:Be
q|~9%Pujg
import net.sf.hibernate.HibernateException; EprgLZ1B
$+tkBM
import org.flyware.util.page.Page; rIXAn4,dTv
import org.flyware.util.page.PageUtil; @=$;^}JS|
VL\6U05Z
import com.adt.bo.Result; |2mEowAd
import com.adt.dao.UserDAO; BM3nZ<%3
import com.adt.exception.ObjectNotFoundException; !Ed';yfz\(
import com.adt.service.UserManager; k]v a
hgm`6TQ
/** C&Rv)j
* @author Joa qp7>_B
*/ @Fo0uy\G
publicclass UserManagerImpl implements UserManager { y'(;!5w
K\uR=L7
private UserDAO userDAO; FsD}Nk=m~
P?>p+dM
/** =ahD'*R^A
* @param userDAO The userDAO to set. *b> ~L
*/ X@TQD
publicvoid setUserDAO(UserDAO userDAO){ )s!x)< d;
this.userDAO = userDAO; /
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} I(C_}I>Wb
LNe-]3wB
/* (non-Javadoc) !dZC-U~
* @see com.adt.service.UserManager#listUser d8av`m
z7NaW e
(org.flyware.util.page.Page) f7mI\$CN
*/ )jnxR${M
public Result listUser(Page page)throws Oq[tgmf
CYz]tv}g:
HibernateException, ObjectNotFoundException { ^!=+$@<
int totalRecords = userDAO.getUserCount(); PQ1\b-I
if(totalRecords == 0) .Zo8KwkFY
throw new ObjectNotFoundException cd\0
@;pTQ
5
I
("userNotExist"); S/8xo@vct]
page = PageUtil.createPage(page, totalRecords); d<xBI,g
List users = userDAO.getUserByPage(page); @dGj4h.
returnnew Result(page, users); =*}|y;I
} R`Q9|yF\
|06G)r&
} u" nyx0<
tlc&Wx
[}.OlR3)
]GRPxh
nNf/$h#;O
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8hdd1lVKO8
Wa
, #
询,接下来编写UserDAO的代码: 9[/Gd{`XC
3. UserDAO 和 UserDAOImpl: +[:}<^p?cG
java代码: ZVViu4]?y
^*RmT
{um~]
/*Created on 2005-7-15*/ hmQD-E{Ab
package com.adt.dao; _ u/N#*D
UDhW Y.`'~
import java.util.List; 5X'[{'i,
#k*e>d$
import org.flyware.util.page.Page; AfyEFnY
^[!LU
import net.sf.hibernate.HibernateException; ji:JLvf]%
>{V]q*[/;Q
/** m;k' j@:
* @author Joa UfXqcyY(
*/ [/6IEt3}B
publicinterface UserDAO extends BaseDAO { nx84l 7<
[26"?};"%
publicList getUserByName(String name)throws LC2t,!RRl&
]hc.cj`\W&
HibernateException; 3}2'PC
.(`#q@73
publicint getUserCount()throws HibernateException; [T.kwQf4$
D>PB|rS@
publicList getUserByPage(Page page)throws xrS;06$
58{6k J@
HibernateException; S+7>Y? B!
(Jy7
} 7C
F-?M!
?FxxH*>"
M5CFW >T
(ybKACx
5l}v
java代码:
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?=$a6o
,_D`0B6o
/*Created on 2005-7-15*/ %TP0i#J
package com.adt.dao.impl; <T,vIXwu+
kO+Y5z6=
import java.util.List; 8 W79
zvL;.U
import org.flyware.util.page.Page; MZv In ZS
h:}oUr8
import net.sf.hibernate.HibernateException; vg5i+ry<
import net.sf.hibernate.Query; @/g%l1$`
aTxss:7]
import com.adt.dao.UserDAO; B~G?&"]
nZ0-
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/** )k&<D*5s
* @author Joa \GO^2&g(
*/ S=*rWh8)%<
public class UserDAOImpl extends BaseDAOHibernateImpl 7LbBS:@3z_
hQv~C4Wfrf
implements UserDAO { 79^Y^.D
_8v8qT}O~4
/* (non-Javadoc) >,yE;zuw
* @see com.adt.dao.UserDAO#getUserByName tt$DWmm
9@9(zUS|
(java.lang.String) !?,7Cu.5#6
*/ |@`F!bnLr
publicList getUserByName(String name)throws d,tGW
%wzDBsX
HibernateException { kj{z;5-dl
String querySentence = "FROM user in class mmE\=i~
%}elh79H*
com.adt.po.User WHERE user.name=:name"; e$u=>=jV]
Query query = getSession().createQuery rVB,[4N
W2?6f:
(querySentence); /zJDQ'k0
query.setParameter("name", name); US[{
Q
return query.list(); 2~h! ouleY
} fkbHfBp[(A
M_lQ^7/
/* (non-Javadoc) &mXJL3iN
* @see com.adt.dao.UserDAO#getUserCount() z~\a]MB
*/ Z?ZiK1) K
publicint getUserCount()throws HibernateException { P MV;A{T
int count = 0; ND $m|V-C
String querySentence = "SELECT count(*) FROM I|8'#QX
^yL6A1
user in class com.adt.po.User"; '#LbIv4
Query query = getSession().createQuery R/Y9t8kk
@TBcVHy
(querySentence); .0+=#G>
count = ((Integer)query.iterate().next :Aj8u\3!@
GrPKJ~{6
()).intValue(); k<(G)7'gm
return count; HI&N&a9C
} xMsSZ{j%5
g?&_5)&
/* (non-Javadoc) 1?%Q"*Y&
* @see com.adt.dao.UserDAO#getUserByPage ;n]GHqzY_
Gmi ^2?Z(
(org.flyware.util.page.Page) {BPNb{dBKr
*/ Hj(ay48
publicList getUserByPage(Page page)throws Lu?MRF
f
]z3!hgTj
HibernateException { >n3w'b
String querySentence = "FROM user in class uy'm2
qw?#~"Ca.
com.adt.po.User"; u-qwG/$E
Query query = getSession().createQuery eYNu78u
6bPoC$<Z
(querySentence); ggn C #$
query.setFirstResult(page.getBeginIndex()) >1uo5,wrF
.setMaxResults(page.getEveryPage()); 9bu}@#4*
return query.list(); K
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} jEU`ko_
Xf
0)i
} v3\
|
B\^myg4
)c*NS7D~f
0APh=Alq
^i+ d 3
至此,一个完整的分页程序完成。前台的只需要调用 _C"=Hy{
C.]\ 4e
userManager.listUser(page)即可得到一个Page对象和结果集对象 W3Gg<!*Uo
:DWvH,{+&
的综合体,而传入的参数page对象则可以由前台传入,如果用 |z.x M>
E3hql3=
webwork,甚至可以直接在配置文件中指定。 p}}pq~EH/
x;N@_FZ7KY
下面给出一个webwork调用示例:
-%f$$7
java代码: 2-G6I92d
?OjZb'+=K
skaPC#u
/*Created on 2005-6-17*/ k|uW~I)
package com.adt.action.user; 80m<OW1
;[nomxu|?
import java.util.List; vNWCv
X 8/9x-E_
import org.apache.commons.logging.Log; 2><=U7~
import org.apache.commons.logging.LogFactory; /6fa
7;
import org.flyware.util.page.Page; X%X`o%AqC
=:fN
import com.adt.bo.Result; U~3uu&/r
import com.adt.service.UserService; 1PGY/c
import com.opensymphony.xwork.Action; 5z/*/F=X
,i]X^z5!
/** I}^Q u0ub
* @author Joa r ,cz
yE/
*/ `|uwR5
publicclass ListUser implementsAction{ ;D8175px;
IN^dJ^1+
privatestaticfinal Log logger = LogFactory.getLog zjE|UK{
v79k{<Ln
(ListUser.class); Xmb001
\|@u)n_
private UserService userService; _s{;9&qX]
WMi$ATq
private Page page; p[LPi5
dgEH]9j&
privateList users; iVaCX Xf '
{u}d`%_.M
/* =# /BCL7
* (non-Javadoc) tRZA`&
* fvE:'( #?
* @see com.opensymphony.xwork.Action#execute() n=F|bW
*/ OK] _.v}
publicString execute()throwsException{ *DDqa?gQb
Result result = userService.listUser(page); b}APD))*H!
page = result.getPage(); HpKF7oJ'N
users = result.getContent(); cM?i _m
return SUCCESS; F=g+R~F
} n9H4~[JiC
[z[<onFIq
/** /LK,:6
* @return Returns the page. 2%Mgg,/~
*/ $-w&<U$E
public Page getPage(){ [`n)2}
k
return page; XG!s+ShFV
} :aHLr[%Mz
TC* 78;r
/** ` W}Bc
* @return Returns the users. E+"m@63
*/ c0U=Hj@@
publicList getUsers(){ (5/>arDn
return users; xJ rKH
} EEJ OJ<
"3;b,<0
/** 2kfX_RK
* @param page )` z{T
* The page to set. o%SD\zk
*/ N|-'Fu
publicvoid setPage(Page page){ ^[g7B"`K5
this.page = page; #d* )W3e2{
} dX;Q\
]"
7=@3cw
H
/** Ri<'apl
* @param users eEmuE H@X
* The users to set. 'DdR2
*/ "6t#
publicvoid setUsers(List users){ pNNvg,hS8
this.users = users; ))xP]Mu v
} 7x''V5*j
FzzV%
/** gp(: o$
* @param userService f&2f8@
* The userService to set. ^Q9!DF m
*/ Sg+0w7:2
publicvoid setUserService(UserService userService){ b[Qe} `W
this.userService = userService; ^rh{
} 0-at#r:
} 2tqj]i
CzfGb4
|r<#>~*
+ t7n6
?,z/+/:
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, ad#4W0@S
Oe)B.{;Ph
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 \r`><d
}!9KxwC(
么只需要: .P#+V$qhv
java代码: lS96sjJp@
w#!b #TNc
=im7RgIBo
<?xml version="1.0"?> J ?^R1
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork xcM*D3
OzA'd\|
1.0//EN" "http://www.opensymphony.com/xwork/xwork- R>;m6Rb_
AD>X'J
u8
1.0.dtd"> zI{~;`tzN
vE{L `,\q
<xwork> PC)aVr?@@
c`O(||UZT
<package name="user" extends="webwork- (T|q]29
COc
t d
interceptors"> GyQ9we~
~5]%+G
<!-- The default interceptor stack name <,+nS%a
m&a 8/5
--> rWULv
<default-interceptor-ref U#6<80Ke
[I6&|Lz>
name="myDefaultWebStack"/> nsN|[E8
&rfl(&\oUi
<action name="listUser" ;hb_jW-0W
PHR:BiMZ
class="com.adt.action.user.ListUser"> V.|#2gC]t
<param _ K Ix7
T*{nf
name="page.everyPage">10</param> ZwOX ,D
<result bnZ~jOHl
bmQ-5SE
name="success">/user/user_list.jsp</result> ~-2Gx
HO`
</action> 9$*O ^
bw8[L;~%_
</package> 8;v/b3
Wy.^1M/n>~
</xwork> @(W{_ mw
>e"vPW*[
g T{WH67u
W)jtTC7
<^da-b>C
Xj5oHHwn
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 %$[#/H7=W
.D{He9
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 <?FkwW\?
^`?M~e2FZ8
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 p;Nq(=]
\
`e4gneQY
9A,ok[J
F[)5A5+:Y
b6UpE`\z
我写的一个用于分页的类,用了泛型了,hoho 9Q>85IiT
8/s?Gz
java代码: c^1tXu|&
y$y!{R@
R3|r`~@@
package com.intokr.util; wl /1~!
} /*U~!t
import java.util.List; VRB!u420
K_ Od u^
/** e+<'=_x {
* 用于分页的类<br> <O0.q.
* 可以用于传递查询的结果也可以用于传送查询的参数<br> I=2b)"t0
* $pJw
p{kN
* @version 0.01 t.Yf8Gy
* @author cheng YY4q99^K
*/ -dS@l'$
public class Paginator<E> { }D[j6+E
privateint count = 0; // 总记录数 txik{' :
privateint p = 1; // 页编号 i:60|ngK
privateint num = 20; // 每页的记录数 .$]-::&
privateList<E> results = null; // 结果 5m2f\^U
(vFO'jtcB-
/** Y/ I32@
* 结果总数 k}0b7er=R
*/ "1Y'VpKm(~
publicint getCount(){ xmi@
XL@t
return count; gy Ey=@L
} %JL P=(
hsHbT^Qm
publicvoid setCount(int count){ 8Dkq+H93
this.count = count; ,lcSJ^yr
} Y?ZzFd,i&
NXX/JJ+w
/** l5/gM[0_7
* 本结果所在的页码,从1开始 L+8{%\UPd
* *WfQi8
* @return Returns the pageNo. CE @[Z
*/ }<^QW't_Y
publicint getP(){ "0 $UnR
return p; _tRRIW"Vx"
} nJ}@9v F/
H[RX~Xk2E
/** a"&cm'\lL
* if(p<=0) p=1 e}+Zj'5
* K3k{q90
* @param p h [@}}6
*/ m/3,;P.6
publicvoid setP(int p){ #$
4g&8
if(p <= 0) sa TS8p z
p = 1; ~REfr}0
this.p = p; [2PPa9F
} ;0lY_ii
hp`ZmLq/[
/** YQcaWd(
* 每页记录数量 ( 8X^pL
*/ uUb`Fy9
publicint getNum(){ x\oSD1t,
return num; ;!A=YXB
} Y5c[9\'\
wjfq"7Q
/** 6qSsr]
* if(num<1) num=1 {1gT{2/~@
*/ ^J;rW3#N8
publicvoid setNum(int num){
C TKeY
if(num < 1) ^YJ%^P
num = 1; U;j\FE^+>
this.num = num; ~+C)0Yn
} XZ@|(_Z
*M/:W =,t
/** &?$mS'P
* 获得总页数 aS``fE;O
*/ |`xM45
publicint getPageNum(){ RO@=&3s
return(count - 1) / num + 1; hd]ts.
} FGzKx9I9
0Py*%}r1
/** a`R_}nus*
* 获得本页的开始编号,为 (p-1)*num+1 g^^pPVK_
*/ VVDW=G
publicint getStart(){ 5M/~|"xk
return(p - 1) * num + 1; 4xH/a1&p=
} FA+"t^q
7]9,J(:Ed
/** _N=f&~T
* @return Returns the results. Nv^byWqu
*/ Ra"hdxH
publicList<E> getResults(){ |Sm/s;&c6
return results; ]6F\a= J
} AvPPsN0
SgYMPBh
public void setResults(List<E> results){ &B]1 VZUp
this.results = results; 9VanR
::XX
} `ZbFky{
3I(;c ,S
public String toString(){ K:^0*5Y-k
StringBuilder buff = new StringBuilder `2hg?(ul
fY6~Z
BvK
(); 0?}n( f!S
buff.append("{"); R1*4
buff.append("count:").append(count); B%tWi
buff.append(",p:").append(p); i4]oE&G
buff.append(",nump:").append(num); j8nkNE]&
buff.append(",results:").append Lx tgf2r
@mmnr?_w
(results); $rlrR'[H
buff.append("}"); y/5GY,z%aL
return buff.toString(); Rw|'LaW
} 'y=N_/+s
GGf<9!:
} Le:(;:eL>t
N/ f7"~+`
>,E^ R `y